7. Heart and Great Vessels

Authors: Dahnert, Wolfgang

Title: Radiology Review Manual, 6th Edition

Copyright 2007 Lippincott Williams & Wilkins

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Heart and Great Vessels

Differential Diagnosis of Cardiovascular Disorders

Congenital Heart Disease

Approach to congenital Heart Disease
	Acyanotic enlarged main pulmonary artery	Cyanotic concave main pulmonary artery
Increased Pulmonary BF + increased C/T ratio	L-R shunts VSD ASD PDA ECD PAPVR	Admixture lesions = bidirectional shunts = T-lesions Transposition Truncus arteriosus TAPVR Tricuspid atresia (without RVOT obstruction) Tingles (single ventricle/atrium)
Normal Pulmonary Blood Flow + normal C/T ratio + pulmonary venous HT	LV outflow obstruction AS Coarctation Interrupted aortic arch Hypoplastic left heart LV inflow obstruction Obstructed TAPVR Cor triatriatum Pulmonary vein atresia Congenital MV stenosis Muscle disease Cardiomyopathy Myocarditis Anomalous LCA
Decreased Pulmonary BF + normal C/T ratio + increased C/T ratio		R-to-L shunts + nonrestrictive intracardiac shunt Tetralogy of Fallot Tricuspid atresia (with PS + nonrestrictive ASD) Pulmonary atresia + nonrestrictive VSD + restrictive intracardiac shunt Pulmonary atresia + ASD without VSD PS with ASD/patent foramen ovale Tricuspid atresia + PS + restrictive ASD Trilogy of Fallot Ebstein anomaly Congenital tricuspid insufficiency

Incidence of CHD in Liveborn Infants

Overall incidence:

8 9:1000 livebirths

• Most common CHD: mitral valve prolapse (5 20%), bicuspid aortic valve (2%) [usually not recognized before late infancy/childhood]

• ASD + VSD + PDA account for 45% of all CHD

• 12 lesions account for 89% of all CHD:

  Ventricular septal defect	30.3%
  Patent ductus arteriosus	8.6%
  Pulmonary stenosis	7.4%
  Septum secundum defect	6.7%
  Coarctation of aorta	5.7%
  Aortic stenosis	5.2%
  Tetralogy of Fallot	5.1%
  Transposition	4.7%
  Endocardial cushion defect	3.2%
  Hypoplastic right ventricle	2.2%
  Hypoplastic left heart	1.3%
  TAPVR	1.1%
  Truncus arteriosus	1.0%
  Single ventricle	0.3%
  Double outlet right ventricle	0.2%

P.580

High-risk pregnancy:

(1) Previous sibling with CHD: 2 5%
(2) Previous 2 siblings with CHD: 10 15% (3) One parent with CHD: 2 10%

Most common causes for CHF + PVH in neonate:

• Left ventricular failure due to outflow obstruction

• Obstruction of pulmonary venous return

CHD Presenting in 1st Year of Life

• VSD

• d-transposition of great vessels

• Tetralogy of Fallot

• Isolated coarctation

• Patent ductus arteriosus

• Hypoplastic left heart syndrome

CHD Compatible with Relatively Long Life

• Mild tetralogy: mild pulmonic stenosis + small VSD

• Valvular pulmonic stenosis: with relatively normal pulmonary circulation

• Transposition of great vessels: some degree of pulmonic stenosis + large VSD

• Truncus arteriosus: delicate balance between systemic + pulmonary circulation

• Truncus arteriosus type IV: large systemic collaterals

• Tricuspid atresia + transposition + pulmonic stenosis

• Eisenmenger complex

• Ebstein anomaly

• Corrected transposition without intracardiac shunt

Juxtaposition of Atrial Appendages

• Tricuspid atresia with transposition

• Complete transposition

• Corrected transposition of great arteries

• DORV

Continuous Heart Murmur

• PDA

• AP window

• Ruptured sinus of Valsalva aneurysm

• Hemitruncus

• Coronary arteriovenous fistula

Presenting Age in CHD
Age	Severe PVH	PVH Shunt Vascularity
0-2 d	Hypoplastic left heart	Hypoplastic left heart
	Aortic atresia	TAPVR above diaphragm
	TAPVR below diaphragm	Complete transposition
	Myocardiopathy in IDM
3-7 d	PDA in preterm infant
7-14 d	CoA + VSD/PDA	Coarctation of aorta
	Aortic valve stenosis	Peripheral AVM
	Peripheral AVM
	Endocardial fibroelastosis
	Anomalous LCA

Syndromes with CHD

5 p (Cri-du-chat) Syndrome

Incidence of CHD:

20%

DiGeorge Syndrome

• = congenital absence of thymus + parathyroid glands

• 1. Conotruncal malformation

• 2. Interrupted aortic arch

Down Syndrome = MONGOLISM = TRISOMY 21

• Endocardial cushion defect (25%)

• Membranous VSD

• Ostium primum ASD

• AV communis

• Cleft mitral valve

• PDA

• 11 rib pairs (25%)

• Hypersegmented manubrium (90%)

Ellis-van Creveld Syndrome

Incidence of CHD:

50%

• polydactyly

• single atrium

Holt-Oram Syndrome

• = UPPER LIMB-CARDIAC SYNDROME

Incidence of CHD:

50%

• ASD

• VSD

• Valvular pulmonary stenosis

• Radial dysplasia

Hurler Syndrome

• Cardiomyopathy

Ivemark Syndrome

Incidence of CHD:

100%

• asplenia

• complex cardiac anomalies

Klippel-Feil Syndrome

Incidence of CHD:

5%

• Atrial septal defect

• Coarctation

Marfan Syndrome = ARACHNODACTYLY

• Aortic sinus dilatation

• Aortic aneurysm

• Aortic insufficiency

• Pulmonary aneurysm

Noonan Syndrome

• Pulmonary stenosis

• ASD

• Hypertrophic cardiomyopathy

Osteogenesis Imperfecta

• Aortic valve insufficiency

• Mitral valve insufficiency

• Pulmonic valve insufficiency

Postrubella Syndrome

• low birth weight

• deafness

P.581




• cataracts

• mental retardation

• 1. Peripheral pulmonic stenosis

• 2. Valvular pulmonic stenosis

• 3. Supravalvular aortic stenosis

• 4. PDA

Trisomy 13 15

• VSD, tetralogy of Fallot, DORV

Trisomy 16 18

• VSD, PDA, DORV

Turner Syndrome (XO) = OVARIAN DYSGENESIS

Incidence of CHD:

35%

• Coarctation of the aorta (in 15%)

• Bicuspid aortic valve

• Dissecting aneurysm of aorta

Williams Syndrome = IDIOPATHIC HYPERCALCEMIA

• peculiar elfinlike facies

• mental + physical retardation

• hypercalcemia (not in all patients)

• 1. Supravalvular aortic stenosis (33%)

• 2. ASD, VSD

• 3. Valvular + peripheral pulmonary artery stenosis

• 4. Aortic hypoplasia, stenoses of more peripheral arteries

Shunt Evaluation

Evaluation of L-to-R Shunts

• AGE

  • Infants:

    • Isolated VSD

    • VSD with CoA/PDA/AV canal

    • PDA

    • Ostium primum

  • Children/adults:

    • ASD

    • Partial AV canal with competent mitral valve

    • VSD/PDA with high pulmonary resistance

    • PDA without murmur

• SEX

  • 99% chance for ASD/PDA in female patient

• CHEST WALL ANALYSIS

  • 11 pair of ribs + hypersegmented manubrium:

  • Down syndrome

  • pectus excavatum + straight back syndrome + funnel chest:

  • prolapsing mitral valve

  • rib notching

• CARDIAC SILHOUETTE

  • absent pulmonary trunk:

    • corrected transposition with VSD; pink tetralogy

  • left-sided ascending aorta:

    • corrected transposition with VSD

  • tortuous descending aorta:

    • aortic valve incompetence + ASD

  • huge heart:

    • persistent complete AV canal (PCAVC); VSD + PDA; VSD + mitral valve incompetence

  • enlarged left atrium:

    • intact atrial septum; mitral regurgitation (endocardial cushion defect, prolapsing mitral valve + ASD)

Differential Diagnosis of L-R Shunts
	RA	RV	PA	LA	LV	Prox. Ao
ASD
VSD
PDA						often

Shunt with Normal Left Atrium

• Precardiac shunt

  • Anomalous pulmonary venous connection

• Intracardiac shunt

  • ASD (8%)

  • VSD (25%)

• Postcardiac shunt

  • PDA (12%)

Aortic Size in Shunts

• Extracardiac shunts

  • aorta enlarged + hyperpulsatile

  • 1. PDA

• Pre- and intracardiac shunts

  • aorta small but not hypoplastic

  • 1. Anomalous pulmonary venous return

  • 2. ASD

  • 3. VSD

  • 4. Common AV canal

Cyanotic heart disease

Chemical cyanosis	= PaO2 94%
Clinical cyanosis	= PaO2 85%

• Decrease in hemoglobin delays detectability!

• Most common cause of cyanosis

in newborn:	transposition of great vessels
in child:	tetralogy of Fallot!

N.B.:

tricuspid atresia = the great mimicker

Increased Pulmonary Blood Flow with Cyanosis

• = ADMIXTURE LESIONS

• = bidirectional shunt with 2 components:

  • mixing of saturated blood (L-R shunt) and unsaturated blood (R-L shunt)

  • NO obstruction to pulmonary blood flow

Evaluation process:

• cardiomegaly

• increased pulmonary blood flow

• concave main pulmonary artery:

  • PA segment absent = transposition

  • PA segment present:

    • L atrium normal (= extracardiac shunt) = TAPVR

    • L atrium enlarged (= intracardiac shunt) = truncus arteriosus

N.B.:

Overcirculation + cyanosis = complete transposition until proven otherwise!

Admixture Lesions = T-lesions

mnemonic:

5 T's + CAD

• Transposition of great vessels = complete TGV VSD

  • Most common cause for cyanosis in neonate

P.582




• Tricuspid atresia with or without transposition + VSD

  • 2nd most common cause for cyanosis in neonate

• Truncus arteriosus

• Total anomalous pulmonary venous return (TAPVR) above diaphragm:

  • supracardiac

  • cardiac (coronary sinus/right atrium)

• Tingle = single ventricle

• Common atrium

• Aortic atresia

• Double-outlet right ventricle (DORV type I)/Taussig-Bing anomaly (DORV type II)

Clues:

• skeletal anomalies: Ellis-van Creveld syndrome (truncus/common atrium)

• polysplenia: common atrium

• R aortic arch: persistent truncus arteriosus

• ductus infundibulum: aortic atresia

• pulmonary trunk seen: supracardiac TAPVR; DORV; tricuspid atresia; common atrium

• ascending aorta with leftward convexity: single ventricle

• dilated azygos vein: common atrium + polysplenia + interrupted IVC; TAPVR to azygos vein

• left-sided SVC: vertical vein of TAPVR

• waterfall right hilum: single ventricle + transposition

• large left atrium (rules out TAPVR)

• prominent L heart border: single ventricle with inverted rudimentary R ventricle; levoposition of right atrial appendage (tricuspid atresia + transposition)

• age of onset 2 days: aortic atresia

Decreased Pulmonary Blood Flow with Cyanosis

• = two components of

  • impedance of blood flow through right heart due to obstruction/atresia at pulmonary valve/infundibulum

  • R-to-L shunt

• pulmonary circulation maintained through systemic arteries/PDA

• normal/decreased pulmonary blood flow

• concave main pulmonary artery

• cardiomegaly

• restrictive intracardiac R-to-L shunt

mnemonic:

P2 TETT

• Pulmonic stenosis with ASD

• Pulmonic atresia

• Tetralogy of Fallot

• Ebstein anomaly

• Tricuspid atresia with pulmonic stenosis

• Transposition of great vessels with pulmonic stenosis

• SHUNT AT VENTRICULAR LEVEL

  • 1. Tetralogy of Fallot

  • 2. Tetralogy physiology (associated with pulmonary obstruction):

    • complete/corrected transposition

    • single ventricle

    • DORV

    • tricuspid atresia (PS in 75%)

    • asplenia syndrome

  • prominent aorta with L/R aortic arch; inapparent pulmonary trunk

  • NORMAL R atrium (without tricuspid regurgitation)

  • NORMAL-sized heart (secondary to escape mechanism into aorta)

  Clues:

  • Skeletal anomaly (eg, scoliosis): tetralogy (90%)

  • Hepatic symmetry: asplenia

  • Right aortic arch: tetralogy, complete transposition, tricuspid atresia

  • Aberrant right subclavian artery: tetralogy

  • Leftward convexity of ascending aorta: single ventricle with inverted right rudimentary ventricle, corrected transposition, asplenia, JAA (tricuspid valve atresia)

• SHUNT AT ATRIAL LEVEL

  mnemonic:

  PET

  • Pulmonary stenosis/atresia with intact ventricular septum

  • Ebstein malformation + Uhl anomaly

  • Tricuspid atresia (ASD in 100%)

  • moderate to severe cardiomegaly

  • R atrial dilatation

  • R ventricular enlargement (secondary to massive tricuspid incompetence)

  • inapparent aorta

  • left aortic arch

Pulmonary Venous Hypertension with Cyanosis

• during 1st week of life

  • 1. Hypoplastic left heart syndrome

    • marked cardiomegaly

  • 2. TAPVR below diaphragm

    • normal cardiac size

• during 2nd week of life

  • 3. Aortic coarctation

  • 4. Aortic atresia

• during 4 6th week of life

  • 5. Critical aortic stenosis

  • 6. Endocardial fibroelastosis

  • 7. Anomalous origin of LCA

  • 8. Atresia of common pulmonary vein

Acyanotic heart disease

Increased Pulmonary Blood Flow without Cyanosis

• = indicates L-R shunt with increased pulmonary blood flow (shunt volume >40%)

• WITH LEFT ATRIAL ENLARGEMENT

  • indicates shunt distal to mitral valve = increased volume without escape defect

  • 1. VSD (25%): small aorta in intracardiac shunt

  • 2. PDA (12%): aorta + pulmonary artery of equal size in extracardiac shunt

  • 3. Ruptured sinus of Valsalva aneurysm (rare)

  • 4. Coronary arteriovenous fistula (very rare)

  • 5. Aortopulmonary window (extremely rare)

• WITH NORMAL LEFT ATRIUM

  • indicates shunt proximal to mitral valve = volume increased with escape mechanism through defect

  P.583

  
  

  • 1. ASD (8%)

  • 2. Partial anomalous pulmonary venous return (PAPVR) + sinus venosus ASD

  • 3. Endocardial cushion defect (ECD) (4%)

Normal Pulmonary Blood Flow without Cyanosis

• OBSTRUCTIVE LESION

  • Right ventricular outflow obstruction

    • at level of pulmonary valve: subvalvular/valvular/supravalvular pulmonic stenosis

    • at level of peripheral pulmonary arteries:

      • peripheral pulmonary stenosis

  • Left ventricular inflow obstruction

    • at level of peripheral pulmonary veins:

      • pulmonary vein stenosis/atresia

    • at level of left atrium: cor triatriatum

    • at level of mitral valve:

      • supravalvular mitral stenosis, congenital mitral stenosis/atresia, parachute mitral valve

  • Left ventricular outflow obstruction

    • at level of aortic valve:

      • anatomic subaortic stenosis, functional subaortic stenosis (IHSS), valvular aortic stenosis, hypoplastic left heart, supravalvular aortic stenosis

    • at level of aorta:

      • interruption of aortic arch, coarctation of aorta

• CARDIOMYOPATHY

  • Endocardial fibroelastosis

  • Hypertrophic cardiomyopathy

  • Glycogen storage disease

• hyperdynamic STATE

  • Noncardiac AVM (cerebral AVM, vein of Galen aneurysm, large pulmonary AVM, hemangioendothelioma of liver)

  • Thyrotoxicosis

  • Anemia

  • Pregnancy

• MYOCARDIAL ISCHEMIA

  • Anomalous left coronary artery

  • Coronary artery disease (CAD)

Pulmonary vascularity

Normal Pulmonary Vasculature

• Vascular Distribution

  • pulmonary vessels within upper perihilum approximate 1/3 of total vascularity

  • pulmonary vessels within lower perihilum approximate 2/3 of total vascularity

• Vascular Tapering

  • pulmonary vessels taper near transition of middle 1/3 to outer 1/3 of lung

• Vascular Caliber

  • straight/slightly concave main pulmonary artery contour (mild convexity is normal in young females)

  • CT:

    • upper limits of normal for main pulmonary artery = 3 cm

    • pulmonary trunk measures <4.5 cm (leftward distance from vertical line at carina to most lateral aspect of main pulmonary artery contour)

    • right interlobar/intermediate pulmonary artery measures 10 15 mm in males and 9 14 mm in females on PA radiographs

    • pulmonary vessel size <1 2 mm in extreme lung periphery

    • arteries within 1st anterior intercostal space measure 3 mm

Normal Pulmonary Vascularity & Normal-sized Heart

mnemonic:

MAN

• Myocardial ischemia

• Afterload (= pressure overload problems)

• Normal

Increased Pulmonary Vasculature

• OVERCIRCULATION

  • = shunt vascularity = arterial + venous overcirculation

  • (a) congenital heart disease (most common)

    • L-R shunts

    • Admixture cyanotic lesions

  • (b) high-flow syndromes

    • Thyrotoxicosis

    • Anemia

    • Pregnancy

    • Peripheral arteriovenous fistula

  • diameter of right descending pulmonary artery larger than trachea just above aortic knob

  • increased size of veins + arteries with size larger than accompanying bronchus (= kissing cousin sign), best seen just above hila on AP view

  • enlarged hilar vessels (lateral view)

  • visualization of vessels below 10th posterior rib

• PULMONARY VENOUS HYPERTENSION

  • redistribution of flow (not seen in younger children)

  • indistinctness of vessels with Kerley lines (= interstitial edema)

  • fine reticulated pattern

  • alveolar edema

• PRECAPILLARY HYPERTENSION

  • enlarged main + right and left pulmonary arteries

  • abrupt tapering of pulmonary arteries

• PROMINENT SYSTEMIC/AORTOPULMONARY COLLATERALS

  • Tetralogy of Fallot with pulmonary atresia (= pseudotruncus)

  • VSD + pulmonary atresia (single ventricle, complete transposition, corrected transposition)

  • Pulmonary-systemic collaterals

  • coarse vascular pattern with irregular branching arteries (from aorta/subclavian arteries)

  • small central vessels despite apparent increase in vascularity

Decreased Pulmonary Vascularity

• = obstruction to pulmonary flow

• vessels reduced in size and number

• hyperlucent lungs

• small pulmonary artery segment + hilar vessels

P.584

Pulmonary artery

Invisible Main Pulmonary Artery

• Underdeveloped = RVOT obstruction

  • Tetralogy of Fallot

  • Hypoplastic right heart syndrome (tricuspid/pulmonary atresia)

• Misplaced pulmonary artery

  • Complete transposition of great vessels

  • Persistent truncus arteriosus

Decreased Diameter of Pulmonary Artery

• Lung cancer

  • Tumor extending >180 of arterial circumference of main pulmonary artery indicates unresectability!

• Mediastinal fibrosis

• Takayasu arteritis

• Chronic thromboembolic disease

Unequal Pulmonary Blood Flow

• Tetralogy of Fallot

  • diminished flow on left side (hypoplastic/stenotic pulmonary artery in 40%)

• Persistent truncus arteriosus (esp. type IV)

  • diminished/increased blood flow to either lung

• Pulmonary valvular stenosis

  • increased flow to left lung secondary to jet phenomenon

Dilatation of Pulmonary Artery

• Idiopathic dilatation of pulmonary trunk

• Pulmonic valve stenosis

  • poststenotic dilatation of trunk + left pulmonary a.

• Pulmonary regurgitation

  • severe pulmonic valve insufficiency

  • absence of pulmonic valve (may be associated with tetralogy)

• Congenital L-to-R shunts

• Pulmonary arterial hypertension

• Aneurysm: mycotic/traumatic

• Intravascular pulmonary metastases

Filling Defect in Pulmonary Artery

• Thromboembolism (99%)

• Nonthrombotic embolus:

  • fat droplets, bubbles of air/nitrogen, tumor, foreign bodies (talc, polymethylmethacrylate particles)

  • Particles mostly too small to be visualized

• Primary sarcoma

Evaluation of Pulmonary vasculature on Erect chest film
	Normal	PAH	PVH Overload	Overload
Distribution (UL:LL)	1:2	1:2	1:1 or 1:2	1:1
Vessel tapering	middle:outer third	variably pruned	outer third	outer third
Vascular caliber		increased	increased	increased
Artery-to-bronchus ratio
upper lung zone	0.85 0.15		1.50 0.25	1.62 0.31
lower lung zone	1.34 0.25		0.87 0.20	1.56 0.28
Vessel margins	sharp	sharp	obscured obscured	obscured

Pulmaonary Hypertension

• = sustained pulmonary arterial pressure in systole >25 mm Hg at rest/ >30 mm Hg during exercise (normal levels, 10 and 15 mm Hg) determined by right heart catheterization secondary to reduction in cross-sectional area of the pulmonary vascular bed with concomitant increase in pulmonary vascular resistance

Definition:	central pulmonary pressure >30 mm Hg
Cause:	cardiac/pulmonary/hepatic disease > primary pulmonary hypertension

• often not clinically recognized until advanced stage

CT:

• vascular signs:

  • main pulmonary artery diameter >29 mm (87% sensitive, 89% specific) measured in the plane of PA bifurcation just lateral to ascending aorta

  • segmental artery-to-bronchus ratio >1 in three lobes

  • diameter ratio of main pulmonary artery to aorta >1 (strong correlation in patients <50 years)

  • diameter of left + right pulmonary artery >16 mm (poor indicator of pulmonary arterial hypertension)

  • pruning of peripheral pulmonary arteries

    • = disproportionate increase in caliber of central fibrous arteries (from sustained increase in flow by a factor of >2) + decrease in caliber of smaller muscular arteries (from vasoconstriction)

  • pulmonary veins

    • small: secondary to precapillary pulmonary HTN

    • enlarged: secondary to left-sided heart disease

  • enlargement of bronchial systemic arteries to >1.5 mm (more common in chronic thromboembolic pulmonary HTN than primary pulmonary HTN)

  • vascular complications:

    • subpleural pulmonary infarcts (with elevated pulmonary venous pressure/underlying malignancy)

    • calcified plaques of central pulmonary arteries (PATHOGNOMONIC)

    • dissection/massive thrombosis of central pulmonary arteries

• lung parenchymal signs:

  • mosaic perfusion without dilatation of bronchi (= increase in vessel diameter in areas of hyperattenuation + tapering of peripheral vessels in areas of hypoattenuation); most common in chronic pulmonary thromboembolism

• mediastinal & cardiac signs:

  • right heart enlargement + hypertrophy:

    • right heart dilatation = ratio of RV:LV > 1:1

    P.585

    
    

    • bowing of interventricular septum toward LV

    • RV myocardial thickness >4 mm

  • dilatation of IVC + coronary sinus

  • reflux of contrast medium into IVC + hepatic veins (usefulness diminishes with injection rate >3 mL/sec)

  • mild pericardial thickening/small pleural effusion

  • adenopathy + septal lines + ground-glass opacities suggestive of pulmonary veno-occlusive disease

  • NO increase of pulsations in middle third of lung

MR:

• RV hypertrophy (in almost 100% if RV systolic pressure exceeds 70 mm Hg):

  • mean thickness of RV wall = 6 mm

• RV dilatation:

  • mean RV end-diastolic volume = 80 mL

  • tricuspid regurgitation (from dilatation of tricuspid valve annulus)

• enlargement of RA + IVC + SVC

• septum straight/bowed toward LV

• diminished RV ejection fraction (mean of 45%)

• reduced distensibility of main pulmonary artery (mean of 8%)

• systolic intraluminal signals in pulmonary arteries (due to slow flow) correlating with severity of PAH

Cx:	central arterial thrombosis, premature atherosclerosis of central elastic + muscular pulmonary arteries, aneurysmal dissection of pulmonary arteries, hypertrophy + dilatation of right side of heart
Dx:	clinical assessment of hemodynamic parameters, medical history, histologic findings

Pulmonary Arterial Hypertension (PAH)

Classification by anatomic level:

• Precapillary cause

  • = changes limited to pulmonary arterial circulation @ level of muscular arteries

  • 1. Chronic thromboembolic disease

  • 2. In-situ pulmonary arterial thrombotic disease (polycythemia, sickle-cell disease)

  • 3. Widespread pulmonary embolism from intra-vascular malignant cells/parasites/foreign material

  • 4. Pulmonary vasculitis (eg, collagen vascular disease, especially scleroderma, CREST, HIV)

  • 5. Long-standing L-to-R shunt = Eisenmenger syndrome with reversal of L-to-R shunt

  • 6. Alveolar hypoventilation syndromes

  • 7. Primary pulmonary hypertension (idiopathic)

• Pulmonary parenchymal disease

  • = mechanical interference with small pulmonary arteries (classified under precapillary cause)

  • Hypoxic lung disease:

    • Chronic obstructive pulmonary disease

    • Interstitial pulmonary fibrosis

    • Ventilatory failure from primary chest wall dysfunction

  • Connective tissue disorder:

    • Scleroderma

    • CREST (calcinosis, Raynaud phenomenon, esophageal motility disorder, sclerodactyly, telangiectasia)

  • Infection:

    • HIV (6 12 compared to general population)

    • Sarcoidosis

    • Tuberculosis

• Postcapillary cause

  • = Pulmonary venous hypertension

  • = findings located in pulmonary venous circulation + between capillary bed and left atrium

  • Left atrial obstruction (usually MV disease, left heart failure, left atrial tumor)

  • Mediastinal fibrosis (narrowing of pulmonary veins), may also affect precapillary vessels

  • Pulmonary veno-occlusive disease (idiopathic)

Pathogenesis:

• hyperkinetic CAUSES

  • L-to-R shunt

  • High cardiac output states: thyrotoxicosis, chronic anemia

• OBLITERATIVE CAUSES

  • vascular = precapillary pulmonary hypertension:

    • Primary plexogenic pulmonary arteriopathy = Primary pulmonary hypertension (PPH)

    • Arteritis (eg, Takayasu)

    • Embolization

      • chronic thromboembolic disease

      • tumor

        • lymphangitic carcinomatosis

      • parasites, eg, schistosomiasis

        • hepatosplenomegaly

      • talc crystals

        • micronodular opacities

        • perihilar fibrotic masses

    • Persistent fetal circulation

    • Pulmonary capillary hemangiomatosis

  • pleuropulmonic disease

    • Chronic interstitial lung disease

      • = cor pulmonale:

      • COPD, emphysema, chronic bronchitis, asthma, bronchiectasis, malignant infiltrate, granulomatous disease, cystic fibrosis, end-stage fibrotic lung, S/P lung resection, idiopathic hemosiderosis, alveolar proteinosis, alveolar microlithiasis

    • Pleural disease + chest deformity: fibrothorax, thoracoplasty, kyphoscoliosis

  • vasoconstrictive

    • Chronic alveolar hypoxia

      • = hypoxic pulmonary arterial hyperperfusion:

      • chronic high altitude, sleep apnea, chronic hypercapnea due to hypoventilation from neuromuscular disease/obesity

    • Portopulmonary hypertension (rare)

• Chronic pulmonary venous hypertension

Cor Pulmonale

mnemonic:

TICCS BEV

• Thoracic deformity

• Idiopathic: primary pulmonary hypertension (1%)

• Chronic pulmonary embolism

• COPD

P.586




• Shunt (ASD, VSD, etc)

• Bronchiectasis

• Emphysema

• Vasculitis

Pulmonary Venous Hypertension (PVH)

• = INCREASED VENOUS PULMONARY PRESSURE = VENOUS CONGESTION

• = postcapillary pulmonary hypertension = primary findings located within pulmonary venous circulation between capillary bed + left atrium

Dx:

uniform/widely variable elevation of pulmonary capillary wedge pressure (PCWP) >15 mm Hg

Cause:

• LEFT VENTRICULAR INFLOW TRACT OBSTRUCTION

  • normal-sized heart with right ventricular hypertrophy

  • prominent pulmonary trunk

  • @ proximal to mitral valve:

    • normal-sized left atrium

    • pulmonary veins

      • TAPVR below the diaphragm

      • Primary pulmonary venoocclusive disease (PVOD)

      • Stenosis of individual pulmonary veins

      • Atresia of common pulmonary vein

    • mediastinum

      • Fibrosing mediastinitis (may also affect precapillary vessels)

      • Constrictive pericarditis

    • left atrium

      • Cor triatriatum

      • Left atrial mass: tumor, clot

      • Supravalvular ring of left atrium

  • @ at mitral valve level = mitral valve stenosis

    • enlarged left atrium

    • 1. Rheumatic mitral valve stenosis regurgitation (99%)

    • enlarged left atrial appendage

    • 2. Congenital mitral valve stenosis

    • 3. Parachute mitral valve (= single bulky papillary muscle)

• LEFT VENTRICULAR FAILURE

  • ABNORMAL PRELOAD with secondary mitral valve incompetence (= volume overload)

    • Aortic valve regurgitation

    • Eisenmenger syndrome (= R-to-L shunt in VSD)

    • High-output failure:

      • noncardiac AVM (cerebral AVM, vein of Galen aneurysm, large pulmonary AVM, hemangioendothelioma of liver, iatrogenic), thyrotoxicosis, anemia, pregnancy

  • ABNORMAL afterload

    • (= pressure overload)

    • = LV outflow tract obstruction

    • Hypoplastic left heart syndrome

    • Aortic stenosis (supravalvular, valvular, anatomic subaortic)

    • Interrupted aortic arch

    • Coarctation of the aorta

  • DISORDERS OF CONTRACTION AND RELAXATION

    • Endocardial fibroelastosis

    • Glycogen storage disease (Pompe disease)

    • Cardiac aneurysm

    • Cardiomyopathy

      • congestive (alcohol)

      • hypertrophic obstructive cardiomyopathy (HOCM), particularly in IDM

        • asymmetric septal hypertrophy (ASH)

        • idiopathic hypertrophic subaortic stenosis (IHSS)

  • MYOCARDIAL ISCHEMIA

    • Anomalous left coronary artery

    • Coronary artery disease (CAD)

Histo:

• primary changes: venous medial hypertrophy + intimal proliferation, marked thickening of venous internal elastic lamina

• secondary changes: capillary bed congestion with adjacent vascular proliferation, interlobular septal and pleural edema + fibrosis, lymphatic dilatation, alveolar hemosiderosis, paraseptal venous infarcts adjacent to complete venous occlusion

Cx:

secondary pulmonary arterial hypertension

• equalization of pulmonary vascularity (PCWP 13 15 mm Hg)

• cephalization of pulmonary vascularity (PCWP 16 18 mm Hg)

• interstitial pulmonary edema (PCWP 19 24 mm Hg)

  • = fluid within peribronchovascular connective tissue:

  • peribronchial thickening/cuffing

  • indistinct vessel margins

  • Kerley B lines = short horizontal reticulations within lateral subpleural lung bases

  • Kerley A lines = 3 4-cm-long lines of interlobular septal thickening radiating from hila to mid and upper lung zones

  • perihilar haze = hilar interstitial edema

  • thickened pleural fissures/pseudoeffusion = fluid within subpleural connective tissue

• alveolar pulmonary edema (PCWP 25 mm Hg) = bilateral perihilar and basilar airspace opacification

• small pleural effusions

Cardiomegaly

• CHF

• Multivalvular disease

• Pericardial effusion

  • absence of pulmonary venous hypertension + hydrostatic edema

Cardiothoracic Ratio

• = widest transverse cardiac diameter widest inside thoracic diameter

• = primarily a measure of LV dilatation

<0.45	normal
0.45 0.55	mild cardiomegaly
>0.55	moderate/severe cardiomegaly
Falsely normal:	with LV enlargement of up to 66%, moderate enlargement of LA + RV
Falsely elevated:	in expiration, in recumbent position

P.587

Vascular Pedicle Width

• = distance on a horizontal line between (1) point where right mainstem bronchus + SVC cross and (2) point where left subclavian artery crosses horizontal line

48 5 mm	normal
>53 mm	in 60% of cardiogenic edema, in 85% of volume overload

Cardiomegaly in Newborn

• NONCARDIOGENIC

  • metabolic:

    • Ion imbalance in serum levels of sodium, potassium, and calcium

    • Hypoglycemia

  • decreased ventilation

    • Asphyxia

    • Transient tachypnea

    • Perinatal brain damage

  • erythrocyte function

    • Anemia

    • Erythrocythemia

  • endocrine

    • Glycogen storage disease

    • Thyroid disease: hypo-/hyperthyroidism

  • infant of diabetic mother

  • arteriovenous fistula

    • Vein of Galen aneurysm

    • Hepatic angioma

    • Chorioangioma

• CARDIOGENIC

  • Arrhythmia

  • Myo-/pericarditis

  • Cardiac tumor

  • Myocardial infarction

  • Congenital heart disease

Abnormal Heart Chamber Dimensions

• LEFT VENTRICULAR VOLUME OVERLOAD

  • VSD

  • PDA

  • Mitral incompetence

  • Aortic incompetence

• LEFT VENTRICULAR HYPERTROPHY

  • Coarctation

  • Aortic stenosis

• RIGHT VENTRICULAR VOLUME OVERLOAD

  • ASD

  • Partial APVR/total APVR

  • Tricuspid insufficiency

  • Pulmonary insufficiency

  • Congenital/acquired absence of pericardium

  • [Ebstein anomaly] not truly RV

• RIGHT VENTRICULAR HYPERTROPHY

  • Pulmonary valve stenosis

  • Pulmonary hypertension

  • Tetralogy of Fallot

  • VSD

• Fixed subvalvular aortic stenosis

• Hypoplastic left/right ventricle, common ventricle

• Congestive cardiomyopathy

Right Atrial Enlargement

Cause:

tricuspid stenosis/regurgitation, ASD, atrial fibrillation, dilated cardiomyopathy, Ebstein anomaly, pulmonary atresia

• RA enlarges in rightward + posterior direction

PA CXR:

• prominent round superior border at junction with SVC

• >5.5 cm from midline to most lateral RA margin

• >2.5 cm from right vertebral margin

• >50% vertical height of RA compared with cardiovascular mediastinal height (from top of aortic arch to base of heart)

LAT CXR:

• sharp horizontal interface with lung above RV

• displacement of heart posterior to IVC mimicking LV enlargement

Right Ventricular Enlargement

Cause:

pulmonary valve stenosis, cor pulmonale, ASD, tricuspid regurgitation, dilated cardiomyopathy, secondary to LV failure

• RV enlarges in anterior, superior + leftward direction causing levorotation of heart

PA CXR:

• Only extreme dilatation causes recognizable signs on frontal view!

• straightening/convexity of left upper cardiac contour

• upturned cardiac apex

• left upper cardiac margin parallels left mainstembronchus as a long convex curvature

• increased distance between left upper cardiac margin + left mainstem bronchus

• small appearance of rotated aortic arch + SVC

• large appearance of main pulmonary artery

LAT CXR:

• prominent convexity of anterior heart border >1/3 distance from anterior cardiophrenic sulcus to sternal angle

Left Atrial Enlargement

Cause:

• acquired: mitral stenosis/regurgitation, LV failure, LA myxoma

• congenital: VSD, PDA, hypoplastic left heart

• LA enlarges in multiple directions

PA CXR:

• right retrocardiac double density with inferomedial curvature (earliest sign)

• >7.0 (female)/7.5 (male) cm distance between midpoint of undersurface of left mainstem bronchus + right lateral LA shadow

• left retrocardiac double density

• >75 splaying of carina with horizontal orientation of distal left mainstem bronchus

P.588




• enlarged left-convex left atrial appendage calcifications (in 90% due to rheumatic heart disease)

LAT CXR:

• increased convexity of posterosuperior cardiac margin

• posterosuperior atrial convexity crosses vertical plane formed by tracheal midline + upper lobe bronchus

• posterior displacement of barium-filled esophagus

• posterior displacement of LUL bronchus

Left Ventricular Enlargement

Cause:

• pressure overload: hypertension, aortic stenosis

• volume overload: aortic or mitral regurgitation, VSD

• wall abnormalities: LV aneurysm, hypertrophic cardiomyopathy

• LV enlarges in posterior, inferior + leftward direction

PA CXR:

• leftward displacement of downturned cardiac apex = left ventricular configuration

• depression of left hemidiaphragm + gastric bubble (with diaphragmatic inversion)

LAT CXR:

• increased convexity of posteroinferior cardiac margin

• posterior cardiac margin projects >1.8 cm posterior to IVC measured at a point 2 cm above intersection of IVC with right hemidiaphragm (Hofman-Rigler rule)

Neonatal cardiac failure

• LEFT-SIDED OBSTRUCTIVE LESIONS

  • Segmental hypoplasia of aorta

  • Critical coarctation of the aorta

  • Aortic valve stenosis

  • Asymmetrical septal hypertrophy/hypertrophic obstructive cardiomyopathy

  • Mitral valve stenosis

  • Cor triatriatum

• VOLUME OVERLOAD

  • Congenital mitral valve incompetence

  • Corrected transposition with left (= tricuspid) AV valve incompetence

  • Congenital tricuspid insufficiency

  • Ostium primum ASD

• MYOCARDIAL DYSFUNCTION/ISCHEMIA

  • Nonobstructive cardiomyopathy

  • Anomalous origin of LCA from pulmonary trunk

  • Primary endocardial fibroelastosis

  • Glycogen storage disease (Pompe disease)

  • Myocarditis

• NONCARDIAC LESIONS

  • AV fistulas: hemangioendothelioma of liver, AV fistula of brain, vein of Galen aneurysm, large pulmonary AV fistula

  • Transient tachypnea of the newborn

  • Intraventricular/subarachnoid hemorrhage

  • Neonatal hypoglycemia (low birth weight, infants of diabetic mothers)

  • Thyrotoxicosis (transplacental passage of LATS hormone)

Congestive Heart Failure & Cardiomegaly

mnemonic:

Ma McCae & Co.

• Myocardial infarction

• anemia

• Malformation

• cardiomyopathy

• Coronary artery disease

• aortic insufficiency

• effusion

• Coarctation

Congenital Cardiomyopathy

mnemonic:

CAVE GI

• Cystic medial necrosis of coronary arteries

• Aberrant left coronary artery/Absent coronary a.

• Viral myocarditis

P.589




• Endocardial fibroelastosis

• Glycogen storage disease (Pompe)

• Infant of diabetic mother/Ischemia

Approach to Acquired Heart Disease
Criteria	Mild-Moderate Cardiomegaly	Moderate Severe Cardiomegaly
C/T ratio	0.45-0.55	>0.55
LA enlargement	pressure overload	volume overload
	mitral stenosis	mitral insufficiency
	decreased LV compliance
	hypertrophic cardiomyopathy
	restrictive cardiomyopathy
Enlargement of ascending aorta	pressure overload	volume overload
	aortic stenosis	aortic insufficiency
Normal LA + aorta	myocardial	myocardial
	acute infarction	dilated cardiomyopathy
	hypertrophic cardiomyopathy	ischemic cardiomyopathy
	restrictive cardiomyopathy
	pericardial	pericardial
	constrictive pericarditis	pericardial effusion

Acquired heart disease

• LA enlargement = MV disease

• dilated ascending aorta = aortic valve disease

• RA enlargement = tricuspid valve disease

Pressure Overload

• Systemic hypertension

• Aortic stenosis

• Mitral stenosis

Decreased Compliance

• Myocardial infarction

• Hypertrophic cardiomyopathy

• Restrictive cardiomyopathy

Volume Overload

• Aortic insufficiency

• Mitral insufficiency

• Tricuspid insufficiency

Aorta

Enlarged Aorta

• PA CXR:

  • aortic knob >4.0 cm measured from indented trachea to most lateral margin of aorta

  • right convex contour above RA margin + lateral displacement of SVC (= dilatation of ascending aorta)

• INCREASED VOLUME LOAD

  • Aortic insufficiency

  • PDA

• POSTSTENOTIC DILATATION

  • Valvular aortic stenosis

• INCREASED INTRALUMINAL PRESSURE

  • Coarctation

  • Systemic hypertension

• MURAL WEAKNESS/INFECTION

  • Cystic media necrosis: Marfan/Ehlers-Danlos syndrome

  • Congenital aneurysm

  • Syphilitic aortitis

  • Mycotic aneurysm

  • Atherosclerotic aneurysm (compromised vasa vasorum)

• LACERATION OF AORTIC WALL

  • Traumatic aneurysm

  • Dissecting hematoma

Aortic Wall Thickening

• Intramural hematoma

  • = aortic dissection without intimal tear

• Aortitis

  • segments of aortic arch + branch vessels

• Atherosclerotic plaque

  • irregular narrowing of aortic lumen

• Adherent thrombus

Aortic Calcifications

Intimal Calcification

Cause:	part of atherosclerotic plaque
Associated with:	inflammatory cells, lipid, vascular smooth muscle cells
Site:	within perimeter of internal elastic lamina

• discrete punctate lesion of radiograph

Medial Calcification

Cause:	aging, diabetes, end-stage renal disease, neuropathy, genetic syndromes
Associated with:	elastin + vascular smooth muscle cells

• linear deposit along elastic lamellae resembling railroad tracks (when severe)

Double Aortic Arch

• Most common + serious type of a complete vascular ring; usually isolated condition

Embryology:	failure of regression of either arch
Incidence:	55% of all vascular rings

Edwards' Hypothetical Aortic Arch Development

Right Aortic Arch with Aberrant Left Subclavian Artery

Right Aortic Arch with Mirror-image Branching

Double Aortic Arch

Aberrant Left Pulmonary Artery

P.590

Age:

usually detected in infancy

• usually asymptomatic

• stridor, dyspnea, recurrent pneumonia

• dysphagia (less common than respiratory symptoms, more common after starting baby on solids)

Location:

descending aorta in 75% on left, in 25% on right side; smaller arch anterior in 80%; right arch larger + more cephalad than left in 80%

• two separate arches arise from single ascending aorta

• each arch joins to form a common descending aorta

• trachea in midline:

  • impressions may be present on both sides of trachea: usually R > L (in older children)

  • trachea narrowed and displaced posteriorly with small anterior impression

• Esophagogram:

  • broad horizontal posterior indentation at the level of 3rd/4th thoracic vertebra (by right arch crossing obliquely to join left arch)

  • bilateral esophageal indentations with a reversed S-shaped configuration (= right indentation higher than left)

• CT:

  • four-artery sign = each arch gives rise to 2 dorsal subclavian + 2 ventral carotid arteries evenly spaced around trachea on section cephalad to aortic arch

  DDx:

  right arch with aberrant left subclavian artery (indistinguishable by esophagogram when dominant arch on right side)

Right Aortic Arch

Incidence:	1 2%
Embryology:	persistence of right aortic arch and right descending aorta + regression of left aortic arch
Course:	to right of trachea + esophagus, over right mainstem bronchus; crosses lower thoracic spine; passes through left hemidiaphragm

Right Aortic Arch

Incidence:	1 2%
Embryology:	persistence of right aortic arch and right descending aorta + regression of left aortic arch
Course:	to right of trachea + esophagus, over right mainstem bronchus; crosses lower thoracic spine; passes through left hemidiaphragm

P.591

Incidence of right aortic arch in CHD:

1.	Truncus arteriosus	35%
2.	Pulmonary atresia	25%
3.	Tetralogy of Fallot	20%
4.	Tricuspid atresia	15%
5.	DORV	12%
6.	TGV	8%
7.	Large VSD	2%

Rare anomalies:

• Corrected transposition

• Pseudotruncus

• Asplenia

• Pink tetralogy

Right Aortic Arch with Aberrant Left Subclavian Artery

• = RAA with ALSA

• = interruption of embryonic left arch between left CCA and left subclavian artery

• Most common type of right aortic arch anomaly

• 2nd most common cause of vascular ring after double aortic arch

Incidence:	1:2,500; 35 72% of right aortic arch anomalies
Associated with:	congenital heart disease in 5 12%:
1. Tetralogy of Fallot	(2/3 = 8%)
2. ASD VSD	(1/4 = 3%)
3. Coarctation	(1/12 = 1%)

• usually asymptomatic (loose ring around trachea + esophagus)

• may be symptomatic in infancy/early childhood provoked by bronchitis + tracheal edema

• may be symptomatic in adulthood provoked by torsion of aorta

• left common carotid artery is first branch of ascending aorta

• left subclavian artery arises from descending aorta via the remnant of the left dorsal aortic root

• bulbous configuration of origin of LSA (= remnant of embryonic left arch) = retroesophageal aortic diverticulum = diverticulum of Kommerell (N.B.: originally described as diverticular outpouching at origin of right subclavian artery with left aortic arch):

  • small rounded density left lateral to trachea

  • impression on left side of esophagus simulating a double aortic arch (by aortic diverticulum or ductus/ligamentum arteriosum)

• vascular ring (= left ductus extends from aortic diverticulum to left pulmonary artery):

  • impression on tracheal air shadow (by right aortic arch)

  • right esophageal indentation (by right aortic arch)

  • masslike density silhouetting top of aortic arch just posterior to trachea on LAT CXR (by aberrant left subclavian artery)

  • broad posterior impression on esophagus (left subclavian artery/aortic diverticulum)

  • small anterior impression on trachea (by left common carotid artery)

  • descending aorta on right side

Right Aortic Arch with Mirror-image Branching

• 2nd most common aortic arch anomaly: 24 60%

• = interruption of embryonic left arch between left subclavian artery and descending aorta; dorsal to left ductus arteriosus

Interruption of Left Aortic Arch Distal to Ductus Arteriosus = Type 1 (common)

Associated with:	cyanotic CHD in 98%:
1. Tetralogy of Fallot	(87%)
2. Multiple defects	(7.5%)
3. Truncus arteriosus	(2 6%)
4. Transposition	(1 10%)
5. Tricuspid atresia	(5%)
6. ASD VSD	(0.5%)

• 25% of patients with tetralogy have right aortic arch!

• 37% of patients with truncus arteriosus have right aortic arch!

• NO vascular ring, NO retroesophageal component

• NO structure posterior to trachea

• R arch impression on tracheal air shadow

• NORMAL barium swallow

Interruption of Left Aortic Arch Proximal to Ductus Arteriosus = Type 2 (rare)

• = true vascular ring (if duct persists); rarely associated with CHD

Right Aortic Arch with Isolated Left Subclavian Artery

• 3rd most common right aortic arch anomaly: 2%

• = interruption of embryonic left arch between

  • left CCA and left subclavian artery and

  • left ductus and descending aorta

  • resulting in a connection of left subclavian artery with left pulmonary artery

Associated with:

tetralogy of Fallot

• left common carotid artery arises as the first branch

• left subclavian artery attaches to left pulmonary artery through PDA

• NO vascular ring, NO retroesophageal component

• congenital subclavian steal syndrome

Right Aortic Arch with Aberrant Left Brachiocephalic Artery

• Similar in appearance to R aortic arch + aberrant L subclavian artery

Left Aortic Arch

Left Aortic Arch with Aberrant Right Subclavian Artery

• = right subclavian artery arises as 4th branch from proximal descending aorta

Incidence:	0.4 2.3% of population; in 37% of Down syndrome children with CHD; Most common congenital aortic arch anomaly!
Associated with:	(1) Absent recurrent pharyngeal n. (2) CHD in 10 15%
Course:	(a) behind esophagus (80%) (b) between esophagus + trachea (15%) (c) anterior to trachea (5%)

P.592

• asymptomatic/dysphagia lusoria (rare)

• soft-tissue opacity crossing the esophagus obliquely upward toward the right shoulder (PATHOGNOMONIC)

• masslike opacity in right paratracheal region

• rounded opacity arising from superior aortic margin posterior to trachea + esophagus on LAT CXR

• dilated origin of aberrant right subclavian artery (in up to 60%) = diverticulum of Kommerell = remnant of embryonic right arch

• unilateral L-sided rib notching (if aberrant right subclavian artery arises distal to coarctation)

Anomalous Innominate Artery Compression Syndrome

• = origin of R innominate artery to the left of trachea coursing to the right

• anterior tracheal compression

• ablation of right radial pulse by rigid endoscopic pressure

• posterior tracheal displacement

• focal collapse of trachea at fluoroscopy

• pulsatile indentation of anterior tracheal wall by innominate artery on MRI

Rx:

surgical attachment of innominate artery to manubrium

Patterns of Vascular Compression of Esophagus and Trachea

Vascular rings

• = anomaly characterized by encirclement of trachea + esophagus by aortic arch + branches

• Usually symptomatic lesions

  • chronic stridor, wheezing, recurrent pneumonia

  • dysphagia, failure to thrive

  • Double aortic arch with R descending aorta + L ductus arteriosus

  • R aortic arch with R descending aorta + aberrant L subclavian artery + persistent L ductus/ligamentum arteriosum

    N.B.:

    left obliterated ductus arteriosus (= ligament of Botallo) passes from L pulmonary a. to descending aorta/L subclavian a.

    • symptoms + radiographic findings identical to double aortic arch

    P.593

    
    

    • indentation on right lateral esophageal wall (by aortic arch)

    • impression on the anterolateral esophageal wall (by ligament of Botallo)

    • origin of L subclavian artery frequently dilated

  • L arch with L descending aorta + R ductus/ligamentum

  • Aberrant L pulmonary artery = pulmonary sling

  • Frequency of CXR findings:

    • frontal CXR:

      • right aortic arch (85%)

      • focal indentation of distal trachea (73%)

    • lateral CXR:

      • anterior tracheal bowing (92%)

      • increased retrotracheal opacity (79%)

      • focal tracheal narrowing (77%)

• OCCASIONALLY SYMPTOMATIC LESIONS

  • Anomalous R innominate artery

  • Anomalous L common carotid artery/common trunk

  • R aortic arch with L descending aorta + L ductus/ligamentum

• USUALLY ASYMPTOMATIC LESIONS

  • L aortic arch + aberrant R subclavian artery

  • L aortic arch with R descending aorta

  • R aortic arch with R descending aorta + mirror-image branching

  • R aortic arch with R descending aorta + aberrant L subclavian artery

  • R aortic arch with R descending aorta + isolation of L subclavian artery

  • R aortic arch with L descending aorta + L ductus/ligamentum

Aortic stenosis

• ACQUIRED

  • Takayasu aortitis

  • Radiation aortitis

  • Aortic dissection

  • Infected aortic aneurysm with abscess

  • Pseudoaneurysm from laceration

  • Atherosclerosis (rare)

  • Syphilitic aortitis (rare)

• CONGENITAL

  • Williams syndrome

  • Neurofibromatosis

  • Rubella

  • Mucopolysaccharidosis

  • Hypoplastic left heart syndrome

Abnormal Left Ventricular Outflow Tract

• LVOT = area between IVS + aML from aortic valve cusps to mitral valve leaflets

• Membranous subaortic stenosis

  • = crescent-shaped fibrous membrane extending across LVOT + inserting at aML

  • diffuse narrowing of LVOT

  • abnormal linear echoes in LVOT space (occasionally)

• Prolapsing aortic valve vegetation

• Narrowed LVOT (<20 mm)

  • Long-segment subaortic stenosis

    • aortic valve closure in early systole with coarse fluttering

    • high-frequency flutter of mitral valve in diastole (aortic regurgitation)

    • symmetric LV hypertrophy

  • ASH/IHSS

    • asymmetrically thickened septum bulging into LV + LVOT

    • systolic anterior motion of aML (SAM)

  • Mitral stenosis

  • Endocardial cushion defect

Situs

• = position/site/location referring to the position of the atria and viscera relative to the midline

  • systemic/right atrium

    • has a broad-based appendage

    • receives blood from IVC

    • has terminal crest + coarse pectinate muscles

  • pulmonary/left atrium

    • has a small narrow appendage

    • receives blood from pulmonary veins

• SITUS SOLITUS = normal/usual situs

  on right side:	systemic atrium trilobed lung liver gallbladder IVC
  on left side:	pulmonary atrium bilobed lung stomach single spleen aorta

  Associated with:

  (a) levocardia	: 0.6 0.8% chance for CHD
  (b) dextrocardia	: 95% chance for CHD

• SITUS INVERSUS

  • = mirror-image arrangement of situs solitus

  Frequency:	0.01%
  on left side:	systemic atrium trilobed lung liver gallbladder IVC
  on right side:	pulmonary atrium bilobed lung stomach single spleen aorta

  Associated with:

  • dextrocardia = situs inversus totalis (usual variant): 3 5% chance for CHD, eg, Kartagener syndrome (in 20%)

  • levocardia (extremely rare): 95% chance for CHD

• SITUS AMBIGUUS = HETEROTAXIA

  • = visceral malposition + dysmorphism associated with indeterminate atrial arrangement

  • Subclassification:

    • Asplenia syndrome = double right-sidedness = right isomerism = Ivemark syndrome

      P.594

      
      

      • both lungs have 3 lobes

      • eparterial bronchi = main bronchus passes superior to ipsilateral main pulmonary artery

    • Polysplenia syndrome = double left-sidedness = left isomerism

      • both lungs have 2 lobes

      • hyparterial bronchi = main bronchus passes inferior to ipsilateral main pulmonary artery

Associated with:

CHD in 50 100%

Situs Anomalies

Cardiac Malposition

• location of heart other than within left hemothorax in situs solitus

• location of heart within left hemithorax when other organs are ambiguous

• Determined by base-apex axis; no assumption is made regarding cardiac chamber/vessel arrangement

• POSITION OF CARDIAC APEX

  • Levocardia = apex directed leftward

  • Dextrocardia = apex directed rightward

  • Mesocardia = vertical/midline heart (usually with situs solitus)

  • atrial septum characteristically bowed into left atrium in cardiac situs solitus with dextrocardia + cardiac situs inversus with levocardia (DDx: juxtapositioned atrial appendages)

• CARDIAC DISPLACEMENT

  • by extracardiac factors (eg, lung hypoplasia, pulmonary mass)

  • Dextroposition

    • suggests hypoplasia of ipsilateral pulmonary artery (PAPVR implies scimitar syndrome)

  • Levoposition

  • Mesoposition

• CARDIAC INVERSION

  • alteration of normal relationship of chambers

  • D-bulboventricular loop

  • L-bulboventricular loop

• TRANSPOSITION

  • = alteration of anterior-posterior relationship of great vessels

Cardiac tumor

Prevalence:

0.001 0.03% (autopsy series)

• Rare often asymptomatic tumors until very large!

• symptoms of cardiopulmonary diseases:

  • congestive heart failure: dyspnea, orthopnea, peripheral edema, paroxysmal nocturnal dyspnea

  • palpitations, heart murmur

  • cough, chest pain

• symptoms caused by peripheral emboli to cerebral/systemic/coronary circulation:

  • syncope

• weight loss, fever, malaise

Location:

intracavitary (obstruction, emboli), intramural (arrhythmia), pericardial (tamponade)

CXR:

• cardiomegaly, pericardial effusion

• signs of CHF

• abnormal cardiac contour

• pleural effusion

Benign Heart Tumor in Adults

• More common than malignant neoplasms

• Myxoma (most common primary cardiac tumor; 50% of all primary cardiac tumors)

• Papillary fibroelastoma (10% of all primary cardiac tumors; most common valvular tumor)

• Lipoma

• Hydatid cyst (uncommon):

  • localized bulge of left cardiac contour

  • curvilinear/spotty calcifications (resembling myocardial aneurysm)

Cx:

may rupture into cardiac chamber/pericardium

Malignant Heart Tumors

Prevalence:

25% of all cardiac tumors in adults;
10% of all cardiac tumors in children

• Sarcoma:

  • Majority of primary malignant cardiac neoplasms!

  • 2nd most common primary cardiac neoplasm

• Rhabdomyosarcoma

  • Most common primary in children

P.595




• Metastatic disease

  • 20 1000 times more frequent than primary tumor!

    • to peri-/epicardium lung > breast > lymphoma > leukemia (most common)

    • myocardium: malignant melanoma; secondary extension to myocardium from epicardium

    • endocardial/intracavitary (in only 5%)

• Lymphoma (rare)

• Malignant teratoma

• Multiple cardiac myxomas

Congenital Cardiac Tumor

Incidence:

1:10,000

• Rhabdomyoma (58%): usually multiple masses

• Teratoma (20%): intrapericardiac, extracardiac

  • multicystic mass

• Fibroma (12%): intramural

  May be associated with:	Gorlin syndrome
  Location:	free LV wall/interventricular septum

  • may be pedunculated

  • calcification and cystic degeneration centrally

  • tendency for slow growth

  Cx:

  fetal hydrops secondary to obstruction, pericardial effusion, fetal arrhythmia, fetal death

• Hemangioma (arise from R atrium, pericardial effusion, skin hemangiomas), lymphangioma, neurofibroma, myxoma, mesothelioma:

  • mass-occupying lesion impinging upon cardiac cavities

Cardiac Tumor by Location

• ENDOCARDIAL/INTRACAVITARY

  • Myxoma

  • Thrombus

  • Myofibroblastic sarcomas (MFH, leiomyosarcoma, fibrosarcoma, myxosarcoma)

• VALVULAR

  • Papillary fibroelastoma

  • Vegetations

  • Thrombus

  • Myxoma

• MYOCARDIAL/INTRAMURAL

  • Rhabdomyoma: multifocal, high signal on T2WI

  • Fibroma: always solitary, calcifications, cystic degeneration, low signal on T2WI

• ENDO-/MYO-/EPICARDIAL

  • Lipoma

  • Sarcoma

  • Primary cardiac lymphoma: right heart, multifocal, extension into pericardium

Cardiac calcifications

Detected by:

• fluoroscopy (at low-beam energies 75 kVp is 57% sensitive)

• < digital subtraction fluoroscopy

• < conventional CT < ultrafast CT (96% sensitive)

• @ Coronary arteries (see below)

• @ Cardiac valves

  • Valvar calcification means stenosis its amount is proportionate to degree and duration of stenosis!

• Aortic valve

  • Valve calcium best seen on lateral view!

  • good correlation between amount of calcium and degree of stenosis:

    • heavy calcification = significant stenosis

    • no calcification = aortic stenosis unlikely

  Cause:	congenital bicuspid valve (70 85%) > atherosclerotic degeneration > rheumatic aortic stenosis (rare), syphilis, ankylosing spondylitis
  Location:	above + anterior to a line connecting carina + anterior costophrenic angle (lateral view)

  • Congenital bicuspid aortic valvular stenosis

    • calcium first detected at an average age of 28 years

    • In patients <30 years aortic valve calcifications are mostly due to a bicuspid aortic valve!

    • usually extensive cluster of heavy dense calcific deposits:

      • nearly circular calcification with interior linear bar (DIAGNOSTIC)

    • poststenotic dilatation of ascending aorta

  • Isolated rheumatic aortic stenosis

    • calcium first detected at an average age of 47 years

    • In patients 30 60 years of age aortic valve calcification suggests rheumatic valve disease!

    • cluster of heavy dense calcific deposits without bicuspid contour

  • Degenerative aortic stenosis

    • calcium first detected at an average age of 54 years

    • In patients >65 years aortic valve calcification in 90% due to atherosclerosis!

    • curvilinear shape of calcium outlining tricuspid leaflets

    • diffuse dilatation + tortuosity of aorta (NO poststenotic dilatation)

• Mitral valve (MV)

  Cause:	rheumatic heart disease (virtually always), infected endocarditis, tumor attached to mitral valve, mitral valve prolapse
  Location:	inferior to a line connecting carina + anterior costophrenic angle (on lateral view)

  • calcium first detected in early thirties when patients become overtly symptomatic

  • a severely calcified MV is usually stenotic, but MV stenosis frequently exists without calcium

  • delicate calcification similar to coronary arteries (DDx: calcium in RCA/LCX)

  • superior-to-inferior motion

• Pulmonic valve

  Cause:

  tetralogy of Fallot, pulmonary stenosis, atrial septal defect

  • calcific pattern similar to calcified mitral valve

• Tricuspid valve (extremely rare)

  Cause:

  rheumatic heart disease, septal defect, tricuspid valve defect, infective endocarditis

• @ Annulus

  • = valve rings serve as fibrous skeleton of the heart for attachment of myocardial fibers + cardiac valves

  • Mitral annulus

    Cause:	degenerative (physiologic in elderly)
    Age:	>65 years; M:F = 1:4
    May be associated with:	mitral valve prolapse

    P.596

    
    

    • Commonly associated with:

      • aortic valve calcium (= aortic stenosis), hypertension, hypertrophic cardiomyopathy

    • dense bandlike calcification starting at posterior aspect + progressing laterally frequently forming a reversed C / O / U / J

    Cx:	mitral insufficiency (due to impaired anterior mitral leaflet), atrial fibrillation, heart block (due to infiltration into posterior wall conduction pathway)
    Prognosis:	doubles risk of stroke

  • Aortic annulus

    • usually in combination with degenerative aortic valve calcification

  • Tricuspid annulus

    Associated with:	long-standing RV hypertension
    Location:	right AV groove

    • bandlike C-shaped configuration

• @ Pericardium

  Cause:	idiopathic pericarditis, rheumatic fever (5%), tuberculosis, viruses, uremia, trauma, radiotherapy to mediastinum
  Location:	calcification over less pulsatile right-sided chambers along diaphragmatic surface, atrioventricular grooves, pulmonary trunk

  • 50% of patients with constrictive pericarditis show pericardial calcifications!

  • clumpy amorphous calcium deposits, frequently in atrioventricular groove

  • diffuse eggshell calcification sparing LA (not covered by pericardium)

  Cx:

  constrictive pericarditis

• @ Myocardium

  Cause:	infarction, aneurysm, rheumatic fever, myocarditis
  Frequency:	in 8% post myocardial infarction; M > F
  Location:	apex/anterolateral wall of LV (coincides with LAD vascular distribution + typical location of LV aneurysms)

  • thin curvilinear contour outlining the aneurysm

  • shaggy laminated calcification suggests calcification of associated mural thrombus

  • coarse amorphous calcifications caused by trauma, cardioversion, infection, endocardial fibrosis

• @ Interventricular septum

  Location:

  triangular fibrous area between mitral + tricuspid annuli (= trigona fibrosa) representing the basal segment of interventricular septum, closely related to bundle of His

  Always associated with:

  • heavy calcification of mitral annulus/aortic valve

  Cx:

  heart block

• @ Left atrial wall

  Cause:

  rheumatic endocarditis

  • diffuse sheetlike form

    • patient usually in CHF + atrial fibrillation

    • curvilinear calcification sparing interatrial septum + posterolateral wall on right side

    • shaggy nodular deposits in atrial appendage

    Cx:

    mural thrombus formation + emboli

    • LA wall calcification indicates atrial fibrillation!

  • localized form

    • nodular calcific scar in posterior wall (= McCallum patch) due to injury from a forceful jet in mitral valve insufficiency

• @ Cardiac tumor

  • atrial myxoma (in 5 10% calcified), rhabdomyoma, fibroma, angioma, osteosarcoma, osteoclastoma

• @ Endocardium

  Cause:

  cardiac aneurysm, thrombus, endocardial fibroelastosis

• @ Pulmonary artery

  Cause:

  severe precapillary pulmonary arterial hypertension, syphilis

• @ Ductus arteriosus

  (a) in adults:	indicates patency of ductus with associated long-standing precapillary pulmonary hypertension
  (b) in children:	ductus likely closed

  • calcium deposition in ligament of Botallo

Coronary Artery Calcification

• The amount of coronary calcification correlates with the extent of atherosclerosis!

• The absence of calcification implies the absence of angiographically significant coronary vessel stenosis!

Cause:	(1) arteriosclerosis of intima (2) M nckeberg medial sclerosis (exceedingly rare)
Histo:	calcified subintimal plaques

Pathophysiology:

• injury to endothelium allows circulating histiocytes to lodge in vessel wall where they are transformed into macrophages; these accumulate lipids ( fatty streaks beneath surface endothelium); lipids calcify; the thin fibrous cap overlying lipid deposits may rupture allowing circulating blood to mount a thrombogenic reaction resulting in narrowing of lumen

• Calcium is deposited as calcium hydroxyapatite in hemorrhagic areas within atheromatous plaques!

Location:	coronary artery calcification triangle = triangular area along mid left heart border, spine, and shoulder of LV containing left main coronary artery, proximal portions of LAD + LCX calcifications
Frequency (autoptic):	LAD (93%), LCX (77%), main LCA (70%), RCA (69%)

CXR (detection rate up to 42%):

• Indicating more severe coronary artery disease

• parallel calcified lines (lateral view)

Fluoroscopy: (promoted as inexpensive screening test)

• asymptomatic population

  • calcifications in 34% in asymptomatic male individuals

  • in 35% of patients with calcifications exercise test will be positive (without calcifications only in 4% positive)

  P.597

  
  

  • calcifications indicate >50% stenosis with 72-76% sensitivity, 78% specificity); frequency of coronary artery calcifications with normal angiogram increases with age; predictive values in population <50 years as good as exercise stress test

• symptomatic population

  • in 54% of symptomatic patients with ischemic heart disease

  • In symptomatic patients 94% specificity for obstructive disease (>75% stenosis) of at least one of the three major vessels!

CT:

(a) electron beam:	threshold of +130 HU
(b) spiral CT:	threshold of +90 HU

Clinical outcome:

• for coronary calcifications detected at fluoroscopy: 5.4% event risk at 1 year (vs. 2.1% without calcification)

• for electron beam CT a calcification score of 100 is highly predictive to identify patients with events

Prognosis:

58% 5-year survival rate with and 87% without calcifications

Pericardium

Pericardial Effusion

• = pericardial fluid >50 mL

• dyspnea, fatigue

• symptoms of cardiac tamponade (50%)

Etiology:

• SEROUS FLUID = transudate congestive heart failure, hypoalbuminemia, irradiation, Dressler syndrome, postpericardiotomy syndrome, myxedema

• BLOOD = hemopericardium

  • iatrogenic: cardiac surgery/catheterization, anticoagulants, chemotherapy, radiation

  • trauma: penetrating/nonpenetrating

  • acute myocardial infarction/rupture

  • rupture of ascending aorta/pulmonary trunk

  • coagulopathy

  • neoplasm: mesothelioma, sarcoma, teratoma, fibroma, angioma, metastasis (lung, breast, lymphoma, leukemia, melanoma)

• LYMPH

  • neoplasm, congenital, cardiothoracic surgery, obstruction of hilum/SVC

• FIBRIN = exudate

  • infection: viral, pyogenic, tuberculous

  • uremia: 18% in acute uremia; 51% in chronic uremia; dialysis patient

  • collagen vascular disease: SLE, rheumatoid arthritis, acute rheumatic fever

  • hypersensitivity

mnemonic:

CUM TAPPIT RV

• Collagen vascular disease

• Uremia

• Metastasis

• Trauma

• Acute myocardial infarction

• Purulent infection

• Post MI syndrome

• Idiopathic

• Tuberculosis

• Rheumatoid arthritis

• Virus

• CXR:

  • normal with fluid <250 mL/in acute pericarditis

  • water bottle configuration = symmetrically enlarged cardiac silhouette

  • loss of retrosternal clear space

  • fat-pad sign = separation of retrosternal from epicardial fat line >2 mm (15%) by water density

  • rapidly appearing cardiomegaly + normal pulmonary vascularity

  • differential density sign = increase in lucency at heart margin secondary to slight difference in contrast between pericardial fluid + heart muscle

  • diminished cardiac pulsations

• CT:

  • fluid of water/higher (blood, infection) density

• MR:

  • transudative fluid is hypointense on T1WI + hyperintense on T2WI

  • proteinaceous/hemorrhagic fluid is hyperintense compared with transudate on T1WI

  • inflammatory pericarditis of uremia/TB may demonstrate pericardial thickening

• ECHO:

  • separation of epi- and pericardial echoes extending into diastole (rarely behind LA)

  • volume estimates by M-mode:

    • separation only posteriorly = <300 mL

    • separation throughout cardiac cycle = 300 500 mL

    • plus anterior separation = >1000 mL

Pneumopericardium

Etiology:	shearing mechanism of injury of the heart during blunt trauma
Path:	tear in fibrous pericardium, usually along the course of the phrenic nerve, allows pneumomediastinal air to enter

• thick shaggy soft-tissue density of fibrous pericardium separated by air from cardiac density

• air limited to distribution of pericardial reflection

Pericardial Tumor

• Pericardial teratoma: benign tumor of infants + children

• Pericardial mesothelioma: malignant tumor of adulthood

DDx:

pericardial invasion (sarcoma, lymphoma)

Vena Cava

Vena cava anomalies

Circumaortic Left Renal Vein

Prevalence:	1.5 8.7%
Etiology:	persistence of anterior intersubcardinal + posterior intersupracardinal anastomosis

• venous collar encircling aorta

• superior left renal vein crosses aorta anteriorly

P.598




• inferior left renal vein receives left gonadal vein + crosses aorta posteriorly 1 2 cm below the superior left renal vein

Significance:

preoperative plan for nephrectomy

Duplicated IVC

• = DOUBLE IVC

Prevalence:	0.2 3%
Etiology:	persistence of both supracardinal veins small/equal-sized left IVC formed by left iliac vein crossover to right IVC via left renal vein/or more inferiorly crossover usually anterior/rarely posterior to aorta
Significance:	recurrent pulmonary embolism after IVC filter placement
DDx:	left gonadal v./ a., inferior mesenteric v.

DOUBLE IVC WITH RETROAORTIC RIGHT RENAL VEIN AND AZYGOS CONTINUATION OF IVC

Etiology:

persistence of left supracardinal v. and dorsal limb of renal collar + regression of ventral limb + failure of formation of right subcardinal-hepatic anastomosis

DOUBLE IVC WITH RETROAORTIC RIGHT RENAL VEIN AND HEMIAZYGOS CONTINUATION OF IVC

Etiology:

persistence of left lumbar + thoracic supracardinal v. + left suprasubcardinal anastomosis + failure of formation of right subcardinal-hepatic anastomosis

• right IVC and right renal vein join the left IVC and continue cephalad as the hemiazygos vein

• hemiazygos vein follows alternative pathways:

  • crosses posterior to aorta at T8-9 and joins the rudimentary azygos vein

  • continues cephalad + joins coronary vein via persistent left SVC

  • accessory hemiazygos continuation to left brachiocephalic vein

• hepatic segment of IVC drains into right atrium

Interrupted IVC with Azygos/Hemiazygos Continuation

see

AZYGOS CONTINUATION

Left IVC

• = TRANSPOSITION OF IVC = SOLITARY LEFT IVC

Prevalence:	0.2 0.5%
Etiology:	persistence of left + regression of right supracardinal vein

• left IVC usually joins left renal vein

• crossover as left renal vein usually anterior/rarely posterior to aorta

DDx:	left-sided paraaortic adenopathy
Significance:	difficult transjugular access to infrarenal IVC filter placement

Persistent Left SVC

• = BILATERAL SVCs

Prevalence:	0.3% of general population; 4.3 11% of patients with CHD
Etiology:	failure of regression of left anterior + common cardinal veins + left sinus horn
May be associated with:	ASD, azygos continuation of IVC
Course:	lateral to aortic arch, anterior to left hilum

• left SVC drains into enlarged coronary sinus (common)

• left SVC drains into LA (rare) creating a R-to-L shunt (increased prevalence of CHD)

• hemiazygos arch formed by left superior intercostal vein + persistent left SVC (20%)

• absent/small left brachiocephalic vein (65%)

• absence of right SVC (10 18%)

• anastomosis between right + left anterior cardinal veins (in 35%)

Retroaortic Left Renal Vein

Prevalence:	1.8 2.1%
Etiology:	persistence of posterior intersupracardinal anastomosis + regression of anterior intersubcardinal anastomosis

• crossover usually below/occasionally at level of right renal vein

IVC Obstruction

• INTRINSIC OBSTRUCTION

  • neoplastic (most frequent)

    • Renal cell carcinoma (in 10%), Wilms tumor

    • Adrenal carcinoma, pheochromocytoma

    • Pancreatic carcinoma, hepatic adenocarcinoma

    • Metastatic disease to retroperitoneal lymph nodes (carcinoma of ovary, cervix, prostate)

  • nonneoplastic

    • Idiopathic

    • Proximally extending thrombus from femoroiliac veins

    • Systemic disorders: coagulopathy, Budd-Chiari syndrome, dehydration, infection (pelvic inflammatory disease), sepsis, CHF

    • Postoperative/traumatic phlebitis, ligation, plication, clip, cava filter, severe exertion

• INTRINSIC CAVAL DISEASE

  • neoplastic

    • Leiomyoma, leiomyosarcoma, endothelioma

  • nonneoplastic

    • Congenital membrane

• EXTRINSIC COMPRESSION

  • neoplastic

    • Retroperitoneal lymphadenopathy (adults) due to metastatic disease, lymphoma, granulomatous disease (TB)

    • Renal + adrenal tumors (children)

    • Hepatic masses

    • Pancreatic tumor

    • Tumor-induced desmoplastic reaction (eg, metastatic carcinoid)

  • nonneoplastic

    • Hepatomegaly

    • Tortuous aorta/aortic aneurysm

    • Retroperitoneal hematoma

    • Massive ascites

    • Retroperitoneal fibrosis

P.599




• FUNCTIONAL OBSTRUCTION

  • Pregnant uterus

  • Valsalva maneuver

  • Straining/crying (in children)

  • Supine position with large abdominal mass

• COLLATERAL PATHWAYS

  • Deep pathway: ascending lumbar veins to azygos vein (right) + hemiazygos vein (left) + intravertebral, paraspinal, extravertebral plexus (Batson plexus)

  • Intermediate pathway: via periureteric plexus + left gonadal vein to renal vein

  • Superficial pathway: external iliac vein to inferior epigastric vein + superior epigastric vein + internal mammary vein into subclavian vein

  • Portal pathway: retrograde flow through internal iliac vein + hemorrhoidal plexus into inferior mesenteric vein + splenic vein into portal vein

Noninfectious Vasculitides

Vasculitis

= inflammation and necrosis of vessel wall

• LARGE-VESSEL VASCULITIS

  • Giant cell (temporal) arteritis

  • Takayasu disease

• MEDIUM-SIZED VESSEL VASCULITIS

  • Polyarteritis nodosa

  • Kawasaki disease

  • Drug-induced vasculitis:

    • methamphetamine

    • cocaine: neurovascular, cardiovascular complications, aortic dissection, venous thrombosis, mesenteric artery thrombosis, renal infarction

• SMALL-VESSEL VASCULITIS

  • ANCA-associated small-vessel vasculitis

    • (= antineutrophil cytoplasmic autoantibodies)

    • Wegener granulomatosis

    • Churg-Strauss syndrome

    • Microscopic polyangitis

  • immune-complex small-vessel vasculitis

    • Henoch-Sch nlein purpura

    • Essential cryoglobulinemic vasculitis

    • Cutaneous leukocytoclastic angitis

    others:

    lupus, rheumatoid, Sj gren, Beh et, Goodpasture, serum sickness, drug-induced, hypocomplementemic urticaria

  • inflammatory bowel disease vasculitis

Multiple Aneurysms

• Polyarteritis nodosa

• Rheumatoid vasculitis

• Systemic lupus erythematosus

• Churg-Strauss syndrome

Cardiac surgery

Surgical Procedures

• AORTICOPULMONARY WINDOW SHUNT

  • = side-to-side anastomosis between ascending aorta and left pulmonary artery (reversible procedure)

  • Tetralogy of Fallot

• BLALOCK-HANLON PROCEDURE

  • = surgical creation of ASD

  • Complete transposition

• BLALOCK-TAUSSIG SHUNT

  • = end-to-side anastomosis of subclavian artery to pulmonary artery, performed ipsilateral to innominate artery/opposite to aortic arch

  • Modified Blalock-Taussig shunt uses synthetic graft material such as polytetrafluoroethylene (Gore-Tex ) in an end-to-side anastomosis between subclavian artery + ipsilateral branch of pulmonary artery

  • Tetralogy of Fallot, tricuspid atresia with pulmonic stenosis

• FONTAN PROCEDURE

  • external conduit from right atrium to pulmonary trunk (= venous return enters pulmonary artery directly)

  • closure of ASD: floor constructed from flap of atrial wall and roof from piece of prosthetic material

  • Tricuspid atresia

• GLENN SHUNT

  • = end-to-side shunt between distal end of right pulmonary artery and SVC; reserved for patients with cardiac defects in which total correction is not anticipated

  • Tricuspid atresia

P.600




• NORWOOD PROCEDURE

  • construction of neoaorta from aortic arch + descending aorta + main pulmonary artery supplying coronary and systemic circulation

  • communication between RV as systemic ventricle and systemic circulation

  • shunt between innominate artery + main pulmonary artery to control pulmonary arterial blood flow

  • excision of distal ductus arteriosus + atrial septum to prevent pulmonary venous hypertension

  • Hypoplastic left heart syndrome

• POTT SHUNT

  • = side-to-side anastomosis between descending aorta + left pulmonary artery

  • Tetralogy of Fallot

• MUSTARD PROCEDURE

  • removal of atrial septum

  • pericardial baffle placed into common atrium such that systemic venous blood is rerouted into left ventricle and pulmonary venous return into right ventricle and aorta

  • Complete transposition

• RASHKIND PROCEDURE

  • = balloon atrial septostomy

  • Complete transposition

• RASTELLI PROCEDURE

  • external conduit (Dacro) with porcine valve connecting RV to pulmonary trunk

  • Transposition

• WATERSTON-COOLEY SHUNT

  • = side-to-side anastomosis between ascending aorta and right pulmonary artery;

    • extrapericardial (WATERSTON)

    • intrapericardial (COOLEY)

  • Tetralogy of Fallot

Postoperative Thoracic Deformity

• ON RIGHT SIDE

  • Systemic-PA shunt: Blalock-Taussig shunt, Waterston-Cooley shunt, Glenn shunt, central conduit shunt

  • Atrial septectomy: Blalock-Hanlon procedure

  • VSD repair: through RA

  • Mitral valve commissurotomy

• ON LEFT SIDE

  • PDA

  • Coarctation

  • PA banding

  • Mitral valve commissurotomy

  • Systemic-PA shunt: Blalock-Taussig shunt, Pott shunt

Heart Valve Prosthesis

• Starr-Edwards

  • caged ball

  • Predictable performance from large long-term experience

• Bj rk-Shiley/Lillehei-Kaster/St. Jude

  • tilting disk

  • Excellent hemodynamics, very low profile, durable

• Hancock/Carpentier-Edwards (= porcine xenograft) Ionescu-Shiley (= bovine xenograft)

  • Low incidence of thromboembolism, no hemolysis, central flow, inaudible

Pulsus Alternans

= alternating arterial pulse height with regular cardiac rhythm

• Intrinsic myocardial abnormality

  • severe left ventricular dysfunction (CHF, aortic valvular disease, hypothermia, hypocalcemia, hyperbaric stress, ischemia)

• Alternating end-diastolic volumes abnormalities in venous filling + return (obstructed venous return, IVC balloon

Mustard Procedure (lateral view into opened right atrium)

P.601

Cardiovascular Anatomy

Normal Blood Pressures

Development of Major Blood Vessels

Right Ventricle Viewed from Front

P.602

Heart size

Cardiothoracic Ratio

• = widest transverse cardiac diameter widest inside thoracic diameter

< 0.5	=	normal in >1 month old (45% sensitive, 85% specific, 59% accurate)
< 0.6	=	normal in <1 month old
Purpose:	measurement of LV dilatation

Dependent on:

• lung volume: CT ratio enlarges in expiration

• patient position: CT ratio increases on supine film

Pitfalls:

• no change unless LV volume increases by >2/3

• no change in moderate enlargement of LA / RV

Heart valve positions

PA CXR:

• reference line = oblique line drawn from distal left mainstem bronchus to right cardiophrenic angle

• aortic valve resides in profile superior to this line overlying the thoracic spine

• pulmonic valve just inferior to left mainstem bronchus

• mitral valve resides inferior to this line centrally located within cardiac silhouette

• tricuspid valve inferior to this line more basilar and midline

LAT CXR:

• reference line = oblique line drawn from carina / right pulmonary artery shadow to anterior cardiophrenic sulcus

• aortic valve resides superior to this line

• pulmonic valve anterior + superior to aortic valve

• mitral valve resides inferoposteriorly to this line

• tricuspid valve inferior to this line anteriorly

Atria

Right Atrium

• Eustachian valve = valve of IVC

  • located at junction of IVC + RA

  • directs blood from IVC to foramen ovale in fetus

  • thin linear structure, not routinely imaged

• Crista terminalis

  • line of fusion between anterior trabeculated portion + smooth-walled posterior portion of RA

  • vertically oriented smooth muscular ridge

Interatrial Septum

• thin septum, difficult to image

• may contain small amount of fat sparing fossa ovalis

DDx:

Lipomatous hypertrophy of interatrial septum
characteristic dumbbell shape due to sparing of fossa ovalis
abnormal amount of fat in older / obese adults

Left Atrium

• ridge of smooth muscle ( bulbous tip) at junction of left atrial appendage and entrance of left superior pulmonary vein

Aortic arch branching patterns

• Standard branching pattern (65 75%)

  • brachiocephalic trunk, left CCA, left subclavian artery

• Common origin of brachiocephalic trunk + left CCA (13%)

• Bovine aortic arch (9%)

  • = origin of left CCA from brachiocephalic trunk

• Vertebral artery (usually left) arising from aortic arch (3%)

• Left and right brachiocephalic trunks (1%)

• Aberrant right subclavian artery as the last branch of the aortic arch (<1%)

Heart Valve Positions

P.603

Parasternal Long-Axis View

Parasternal Long-and Short-Axis

Diagram of the Relationship of the four Cardiac Valves in Cross Section

Echocardiogram of Aortic Root
Aortic root dimension	measured at enddiastole at R-wave of ECG	2.1-4.3 cm
increased in:	aneurysm of aorta, aortic insufficiency
Aortic cusp separation		1.7-2.5 cm
decreased in:	aortic stenosis, low stroke volume
increased in:	aortic insufficiency
Left atrial diameter	measured at moment of mitral valve opening	2.3-4.4 cm
Eccentricity index of aortic valve cusps	ratio of anterior to posterior dimension(rarely used)	<1.3
Ratio of LA-to-aorticroot dimension		0.87-1.11

Echocardiogram of Right and left ventricle
Rv end-diastolic dimension	at R-wave of ECG	0.7-2.3 cm
increased in:	RV volume overload
Septal thickness	end-diastolic thickness at R-wave of ECG	0.9 0.06 cm
decreased in:	CAD
increased in:	asymmetric septal hypertrophy, IHSS
LV end-diastolic dimension	at R-wave of ECG	4.6 0.54 cm
LVPW thickness	end-diastolic thickness at peak of R-wave	0.94 0.09 cm
increased in:	LV hypertrophy
LV end-systolic dimension		2.9 0.5 cm
IVS:LVPW thickness		<1.3
Fractional shortening	(EDD - ESD)/EDD 100
for LV		25-42%
for IVS		28-62%
for LVPW		36-70%

P.604

Cervical Aortic Arch

Associated with:

right aortic arch (in 2/3)

• pulsatile neck mass

• upper airway obstruction

• dysphagia

• mediastinal widening

• absence of normal aortic knob

• aortic arch near lung apex

• tracheal displacement to opposite side + anteriorly

• apparent cutoff of tracheal air column (secondary to crossing of descending aorta to side opposite of arch)

DDx:

carotid aneurysm

Aortic isthmus variants

Aortic Isthmus

• = narrowing of the aorta in newborn between left subclavian artery and ductus arteriosus

Age:	up to 2 months of age
Prognosis:	aortic isthmus disappears due to cessation of flow through ductus arteriosus + increased flow through narrowed region

Aortic Spindle (16%)

• = congenital narrowing of the aorta at the ligamentum arteriosum with distal fusiform dilatation

Ductus Diverticulum

• = localized bulge along anteromedial aspect of aortic isthmus

Origin:	remnant of enlarged mouth of ductus arteriosus / result of traction from ligamentum arteriosum
Frequency:	in 33% of infants, in 9% of adults

• focal bulge with smooth uninterrupted margins:

  • gently sloping symmetric shoulders (classic ductus diverticulum)

  • shorter steeper slope superiorly + more gentle slope inferiorly (atypical ductus diverticulum)

DDx:

posttraumatic false aneurysm

Prominent Bronchial-intercostal Trunk

 

Coronary arteries

Anatomy of Right Coronary Artery (RCA)

• arises from anterior right coronary sinus;

• travels within right atrioventricular sulcus;

• rounds the acute margin of the heart

• Conus artery (CB)

  • = 1^st branch from RCA (in 50% directly from aorta) to supply RVOT

• Sinoatrial node artery (SANA)

  • = 2^nd branch from RCA (in >50%)

• Acute / RV marginal branches (M1, M2, etc)

  • have an anterior course

• Posterior descending artery (PDA)

  • originates from RCA near crux or from a distal acute marginal branch;

  • supplies posterior third of ventricular septum + diaphragmatic segment of LV;

  • supplies blood to posteromedial papillary muscle

• Atrioventricular node artery (AVNA)

  • = small branch to AV node

• Posterolateral segment arteries (PLSA)

  • supplies posterolateral wall of LV

Normal Aortic Isthmus Variants in 45 LAO Projection

Anatomy of Left Coronary Artery (LCA)

• arises from left posterior coronary sinus

• Left main coronary artery (LM)

  • 0.5 2.0 cm short stem before bi- / trifurcation

• Left anterior descending (LAD)

  • travels within anterior interventricular groove, gives blood supply to anterolateral papillary muscle

  • (a) Diagonal branches (D1, D2, etc)

    • arise from LAD and course over anterolateral wall of LV

    mnemonic:

    Diagonals from LAD
    occasionally trifurcation into LAD + LCx
    + ramus intermedius (in a course similar to D1)

  • (b) Septal branches (S)

    • for anterior interventricular septum

• Left circumflex artery (LCx)

  • travels within left atrioventricular sulcus;

  • terminates at obtuse margin of heart

  • (a) Obtuse marginal branches (OM1, OM2, etc)

    • for lateral wall of LV

  • (b) Left atrial circumflex artery (LACX)

    • for atrium

Coronary Artery Territory

septum	= LAD
anterior wall	= LAD
lateral wall	= LCx
posterior wall	= RCA
inferior / diaphragmatic wall	= RCA
apex + inferolateral wall	= watershed areas

Coronary Artery Dominance

• determined by the artery that crosses the crux and serves as origin of the posterior descending artery (PD), which supplies the inferior portion of LV:

• from RCA in 85% (= right dominance)

• from LCx in 8% (= left dominance)

• RCA + LCA = codominance / balanced supply (7%)

Coronary Arteriography

Contrast agents:

• Monomeric ionic contrast material:

  P.605

  
  

  • negative inotropic = depression of myocardial contractility due to hyperosmolality of sodium + decrease in total calcium

  • peripheral vasodilatation

• Meglumine diatrizoate (contains small quantities of sodium citrate + EDTA)

• Nonionic contrast material = slight increase in LV contractility

Dose:	3 10 mL
Mortality:	0.05%

Risk factors associated with death:

• Multiple ventricular premature contractions

• Congestive heart failure

• Systemic hypertension

• Severe triple-vessel coronary artery disease (highest risk)

• LV ejection fraction <30%

• Left main coronary artery stenosis

Clues for projection:

45 70 LAO:

• ribs slanting to left side of image

• catheter in descending aorta on right side of image

15 30 RAO:

• ribs slanting to right side of image

• catheter in descending aorta on left side of image

Technique:

• 20 30 of cranial / caudal angulation variably used

• Catheter in left coronary orifice:

  • (a) LAO + caudocranial angulation:

    • proximal 1/3 of LAD + origin of first diagonal branch

  • (b) LAO + craniocaudal angulation = spider view :

    • LCA, proximal LCx, first marginal / diagonal branches

  • (c) RAO + craniocaudal angulation:

    • proximal third of LCx + origin of its branches

  • (d) RAO + caudocranial angulation:

    • separation of LAD from diagonal branches

• Catheter in right coronary artery orifice: LAO plusmn; RAO

False-negative interpretation:

• eccentric lesion in 75%

• foreshortening of vessel

• overlap of other vessels remedied by angulated projections: improved diagnosis (50%), upgrade to more significant stenosis (30%), lesion unmasked (20%)

AP View of Heart and Coronary Arteries

Anomalies of the Coronary Arteries

Coronary Artery Collaterals

• intracoronary COLLATERALS

  • = filling of a distal portion of an occluded vessel from the proximal portion

  • tortuous course outside the normal path

• intercoronary COLLATERALS

  • = between different coronary arteries / between branches of the same artery

  P.606

  
  

  

  Right and Left Coronary Artery Angiograms

  P.607

  
  

  

  Coronary Artery Angiograms of Varying Dominance

  Location:

  on epicardial surface, in atrial / ventricular septum, in myocardium

  • Proximal RCA to distal RCA

    • by way of acute marginal branches

    • from sinoatrial node artery (SANA) to atrioventricular node artery (AVNA) = Kugel collateral

  • RCA to LAD

    • between PDA and LAD through ventricular septum / around apex

    • conus artery (1st branch of RCA) to proximal part of LAD

    • acute marginals of RCA to right ventricular branches of LAD

  • Distal RCA to distal LCx

    • posterolateral segment artery of RCA to distal LCx (in AV groove)

    • AVNA of RCA to LCx (through atrial wall)

    • posterolateral branch of RCA to obtuse marginal branches of LCx (over left posterolateral ventricular wall)

  • Proximal LAD to distal LAD

    • proximal diagonal to distal diagonal artery of LAD

    • proximal diagonal to LAD directly

  • LAD to obtuse marginal of LCx

Coronary Artery Anomalies

Incidence:

0.3 1%; in 25% responsible for nontraumatic sudden death in young adults

Anomaly of Origin

• High takeoff (6%)

  • = origin of RCA / LCA above the junctional zone between sinus + tubular part

• Multiple ostia

  • RCA + conus branch arise separately

  • LAD + LCx arise separately without LCA (0.41%)

• Single coronary artery (0.0024 0.044%)

• Anomalous origin from the pulmonary artery

  • Bland-White-Garland syndrome

    • = LCA arises from PA + RCA arises from aorta

    Prevalence:

    1:300,000 live births

    • collateral circulation between RCA + LCA

    • coronary steal into PA

    Prognosis:

    death in 1st year of life in 90%

• Origin of coronary artery from opposite sinus / noncoronary sinus

  • RCA arising from left coronary sinus (0.03 0.17%)

  • LCA arising from right coronary sinus (0.09 0.11%)

  • LCx / LAD arising from right coroanry sinus (0.32 0.67%)

  • LCA / RCA arising from noncoronary sinus

  may take the following course:

  • interarterial (between aorta + pulmonary trunk) with a high risk of sudden cardiac death

  • retroaortic

  • prepulmonic

  • septal (subpulmonic / beneath RVOT

P.608

Pericardial Sinuses & Recesses

Anomaly of Coronary Artery Course

• Myocardial bridging

  • = band of myocardial muscle overlying a segment of a coronary artery

• Duplication of arteries, eg., LAD

Anomaly of Termination

• Coronary artery fistula (0.1 0.2%)

  • = communication between coronary artery (RCA in 60%, LCA in 40%, both in <5%) and cardiac chamber (RV in 45%, RA in 25%) / pulmonary artery (in 15%) / coronary sinus / SVC

  • dilated tortuous coronary artery

  • single / multiple communications / network of fine vessels

  Cx:

  myocardial ischemia

• Coronary arcade

  • = angiographically demonstrable communication between RCA and LCA in the absence of a coronary artery stenosis

  • prominent straight connection near crux

  DDx:

  tortuous collateral vessel

• Extracardiac termination

  Cause:	atherosclerotic CAD
  Receiver:	bronchial, internal mammary, pericardial, anterior mediastinal, superior / inferior phrenic, intercostal arteries

Pericardium

Pericardial thickness:

1-3 mm

• FIBROUS PERICARDIUM

  • = outer fibrous layer

• SEROUS PERICARDIUM

  • = inner serous sac forming the pericardial cavity

  • contains 20 50 mL of serous fluid

  • (a) inner visceral layer = epicardium

    • intimately connected to heart + epicardial fat

  • (b) outer parietal layer

    • lines fibrous pericardium

Pericardial sinuses and Recesses

• = extensions of pericardial cavity

• Recesses of pericardial cavity proper

  • Postcaval recess (23%*)

    • behind and right lateral to SVC

  • Right pulmonic vein recess (29%*)

    • behind and right lateral to SVC

  • Left pulmonic vein recess (60%*)

    • behind and right lateral to SVC

• Transverse sinus

  • posterior to ascending aorta and pulmonary trunk + above left atrium (95%*)

  • 1. Superior aortic recess

    • along ascending aorta; may be divided into anterior, posterior, right lateral portion

    DDx:

    aortic dissection on NECT

  • 2. Left pulmonic recess

    • below left pulmonary artery + posterolateral to proximal right pulmonary artery

  • 3. Right pulmonic recess

    • below right pulmonary artery + above left atrium

  • 4. Inferior aortic recess

    • between ascending aorta + inferior SVC / right atrium

    • extending down to level of aortic valve

• Oblique sinus (89%*)

  • behind left atrium + anterior to esophagus

  • separated from transverse sinus by double reflection of pericardium (and fat) between right + left superior pulmonic veins

  • 1. Posterior pericardial recess (67%*)

    • behind distal right pulmonary artery + medial to bronchus intermedius

      P.609

      
      

      DDx:

      lymph nodes, esophageal / thymic process, vascular abnormality, pericardial cyst / tumor

    • * = percentages give depiction on HRCT

Development of the Major-Venous System

Embryogenesis Of Vena Cava

Time of development:

6-8th week of embryonic life

Origin:

• Vitelline (omphalomesenteric) venous system:

  • blood from yolk sac to sinus venosus

• Umbilical venous system

  • blood from chorionic villi to sinus venosus via ductus venosus

• Intraembryonic cardinal venous system

  • continuous appearance + regression of 3 paired embryonic veins

  • (1) Cardinal veins

    • join to form common cardinal vein, which enters left + right sinus horns

    • (a) anterior cardinal veins

      • drain the cranial region

    • (b) posterior cardinal veins

      • drain body of embryo + mesonephros + anterior extremities

    Location:

    dorsolateral part of urogenital fold

  • (2) Subcardinal veins

    • drain urogenital system of metanephros + suprarenal glands

      Location:

      ventromedial to posterior cardinal veins + ventrolateral to aorta

    • Intersubcardinal anastomoses form anterior to aorta below superior mesenteric artery and connect left + right subcardinal veins

  • (3) Supracardinal veins

    • drain body wall via intercostal veins

    Location:

    dorsomedial to posterior cardinal vein + dorsolateral to aorta

    • CRANIAL

      • azygos vein on the right

        • drains 4 11 right intercostal veins

      • portion of superior intercostal vein

        • drains 2 3 left intercostal veins

      • accessory hemiazygos

        • drains 4 7 left intercostal veins

      • hemiazygos vein

        • drains left 8 11 intercostal veins

    • CAUDAL: lumbar veins

P.610

Inferior Vena Cava

• Hepatic = posthepatic segment

  Origin:

  terminal part of right vitelline vein

• Suprarenal segment

  Origin:

  subcardinal-hepatic anastomosis

• Renal segment

  Origin:

  part of right subcardinal vein + supracardinal-subcardinal anastomoses

• Infrarenal segment

  Origin:

  right supracardinal / sacrocardinal vein

Venous system of lower extremity

Deep Veins of Lower Extremity

• 3 paired stem veins of the calf accompany the arteries as venae commitantes + anastomose freely with each other:

• 1. Anterior tibial veins

  • draining blood from dorsum of foot, running within extensor compartment of lower leg close to interosseous membrane

• 2. Posterior tibial veins

  • formed by confluence of superficial + deep plantar veins behind ankle joint

• 3. Peroneal veins

  • directly behind + medial to fibula

• 4. Calf veins

  • Soleal muscle veins

    • baggy valveless veins in soleus muscle (= sinusoidal veins); draining into posterior tibial + peroneal veins or lower part of popliteal vein

  • Gastrocnemius veins

    • thin straight veins with valves; draining into lower + upper parts of popliteal vein

• 5. Popliteal vein

  • formed by stem veins of lower leg

• 6. Femoral / superficial femoral vein

  • continuation of popliteal vein; receives deep femoral vein about 9 cm below inguinal ligament

• 7. Deep femoral vein

  • draining together with superficial femoral vein into common femoral vein; may connect to popliteal vein (38%)

• 8. Common femoral vein

  • formed by confluence of deep + superficial femoral vein; becomes external iliac vein as it passes beneath inguinal ligament

Superficial Venous System of Lower Extremity

Deep Venous System of Lower Extremity

P.611

Inguinal Arterial Anatomy (right side)

Superficial Veins of Lower Extremity

• Greater saphenous vein

  • formed by union of veins from medial side of sole of foot with medial dorsal veins; ascends in front of medial malleolus; passes behind medial condyles of tibia + femur

  • (a) Posterior arch vein

    • connected to deep venous system by communicating veins

  • (b) Anterior superficial tibial vein

  • (c) Posteromedial superficial thigh vein

    • often connects with upper part of lesser saphenous vein

  • (d) Anterolateral superficial thigh vein

  • (e) Tributaries in fossa ovalis

    • superficial inferior epigastric vein

    • superficial external pudendal vein

    • superficial circumflex iliac vein

• Lesser saphenous vein

  • originates at outer border of foot behind lateral malleolus as continuation of dorsal venous arch; enters popliteal vein between heads of gastrocnemius in popliteal fossa within 8 cm of knee joint (60%) or joins with greater saphenous vein via posteromedial / anterolateral superficial thigh veins (20%)

Communicating = Perforating Veins

• >100 veins in each leg

• MEDIAL

  • Submalleolar communicating vein

  • Cockett group

    • group of 3 veins located 7, 12, 18 cm above the tip of medial malleolus connecting posterior arch vein with posterior tibial vein

  • Boyd vein

    • located 10 cm below knee joint connecting main trunk of greater saphenous vein to posterior tibial veins

  • Dodd group

    • group of 1 or 2 veins passing through Hunter canal (= subsartorial canal) to join greater saphenous vein with superficial femoral vein

• LATERAL

  • Lateral communicating vein

    • located from just above lateral malleolus to junction of lower-to-mid thirds of calf connecting lesser saphenous vein with peroneal veins

  • Posterior mid-calf communicating veins

    • located posteriorly 5 + 12 cm above os calcis joining lesser saphenous vein to peroneal veins

  • Soleal + gastrocnemius points

    • joining short saphenous vein to soleal / gastrocnemius veins

Contents of femoral triangle

mnemonic:

NAVEL (from lateral to medial)

• Nerve

• Artery

• Vein

• Empty space

• Lymphatics

Pulsatility

• = assessment of vascular resistance (increased resistance reduces diastolic flow)

• Can be assessed in vessels too small / tortuous to be imaged (Doppler angle unnecessary)!

• Index should be calculated for each of several cardiac cycles (5 heartbeats adequate) an average value taken

  • S = A = maximal systolic shift

  • D = B = end-diastolic frequency shift

• 1. Full pulsatility index of Gosling (PI_F) = 1/A₀² SA_i²

• 2. Simplified pulsatility index (PI) = (S - D)/mean

• 3. Resistance index (RI) = Pourcelot index = (S- D)/S or 1 - (D/S)

• 4. Stuart index = A/B ratio = S/D ratio

• 5. B/A ratio = B(100%)/A

Pulsatility

P.612

Doppler Waveforms of Hepatic Veins

P.613

Cardiovascular Disorders

Aberrant Left Pulmonary Artery

• = LEFT PULMONARY ARTERY SLING

Embryology:	failure of development/obliteration of left 6th aortic arch (= vascular pedicle for left lung); left lung parenchyma maintains a connection with right lung leading to development of a collateral branch of the right pulmonary artery to supply the left lung
Site:	left PA passes above right mainstem bronchus + between trachea and esophagus on its way to left lung (= sling around proximal right main bronchus + distal trachea)
Age at presentation:	neonate to adulthood

Classification:

• Normal bronchial pattern

• Malformation of bronchotracheal tree

  Associated with:

  • napkin-ring trachea = absent pars membranacea (50%)

  • Stenosis of long tracheal segment

  • PDA (most common), ASD, persistent left SVC

• stridor (most common), wheezing, apneic spells, cyanosis

• respiratory infection

• feeding problems

• deviation of trachea to left

• inverted-T appearance of mainstem bronchi = horizontal course secondary to lower origin of right mainstem bronchus

• anterior bowing of right mainstem bronchus

• carrot-shaped trachea = narrowing of tracheal diameter in caudad direction resulting in functional tracheal stenosis

• obstructive emphysema/atelectasis of RUL + LUL

• low left hilum

• separation of trachea + esophagus at hilum by soft-tissue mass

• anterior indentation on esophagogram

Amyloidosis

• = extracellular deposits of insoluble fibrillar protein

• asymptomatic/CHF (restrictive cardiomyopathy), arrhythmia

CXR:

• normal/generalized cardiomegaly

• pulmonary congestion

• pulmonary deposits of amyloid

NUC:

• striking uptake of Tc-99m pyrophosphate greater than bone (50 90%)

ECHO:

• granular sparkling appearance of myocardium

• LV wall thickening

• decreased LV systolic + diastolic function

Anomalous Left Coronary Artery

• = left coronary artery arises from pulmonary trunk (left sinus of Valsalva)

Hemodynamics:

• with postnatal fall in pulmonary arterial pressure perfusion of LCA drops (ischemic left coronary bed), collateral circulation from RCA with flow reversal in LCA

  • adequate collateral circulation = lifesaving

  • inadequate collateral circulation = myocardial infarction

  • large collateral circulation = L-to-R shunt with volume overload of heart

• episodes of sweating, ashen color (angina symptomatology)

• ECG: anterolateral infarction

• continuous murmur (if collaterals large)

• dilatation of LV

• enlargement of LA

• normal pulmonary vascularity/redistribution

Rx:	(1) Ligation of LCA at its origin from pulmonary trunk (2) Ligation of LCA + graft of left subclavian artery to LCA (3) Creation of an AP window + baffle from AP window to ostium of LCA
DDx:	endocardial fibroelastosis, viral cardiomyopathy (NO shocklike symptoms)

Anomalous Pulmonary Venous Return

• = lack of an appropriate connection of the primitive pulmonary vein to the left atrium with persistence of fetal pulmonary + systemic connections

Total Anomalous Pulmonary Venous Return

• = entire pulmonary venous return directed to RA = TAPVR = admixture lesion because of the combination of cyanosis + increased pulmonary vascularity (L-to-R and R-to-L shunt)

Embryology:	anomalous connection between pulmonary veins and systemic veins secondary to embryologic failure of the common pulmonary vein to join the posterior wall of the left atrium
Prevalence:	2% of CHD
Age:	symptomatic in 1st year of life

• cyanosis

Hemodynamics:

• obstruction along the pulmonary venous pathway

  

Associated with:

• asplenia; ASD/patent foramen ovale (necessary for survival), bronchopulmonary sequestration, pulmonary arteriovenous malformation, cystic adenomatoid malformation

MR:

• retroatrial sign = presence of veins posterior to LA

• small LA without pulmonary venous connections

• patent foramen ovale/ASD

• anomalous vein with variable location

Overall prognosis:

75% mortality rate within 1 year of birth if untreated

P.614

Supradiaphragmatic TAPVR (82%)

Type I	= SUPRACARDIAC TAPVR (52%) = drainage into left brachiocephalic vein/right + left persistent SVC/azygos vein by way of a vertical vein; <10% obstructed
Type II	= CARDIAC TAPVR (30%) = drainage into coronary sinus (80%)/RA

Hemodynamics:

• functional L-to-R shunt from pulmonary veins to RA

• increased pulmonary blood flow (= overcirculation)

• obligatory R-to-L shunt via usually patent foramen ovale/ASD restores oxygenated blood to left side

• normal systemic venous pressure with increased flow through widened SVC

• after birth CHF secondary to

  • mixture of systemic + pulmonary venous blood in RA

  • volume overload of RV

Age:

presentation <1 years of age

• cyanosis

• neck veins undistended (shunt level distally)

• R ventricular heave (= increased contact of enlarged RV with sternum)

• systolic ejection murmur (large shunt volume)

• overall heart size notably normal:

  • slightly enlarged RV (= volume overload with time)

  • normal/enlarged RA

  • normal LA (= ASD acts as escape valve)

• dilated SVC + left vertical vein:

  • figure of 8 / snowman configuration of cardiac silhouette (= dilated SVC + left vertical vein)

  • pretracheal density on lateral film (= left vertical vein)

• increased pulmonary blood flow (= overcirculation)

• absent connection of pulmonary veins to LA

Sub-/Infradiaphragmatic TAPVR (12%)

• = type III

• = drainage into portal vein/IVC/ductus venosus/left gastric vein with constriction of descending pulmonary vein by diaphragm en route through esophageal hiatus leading to pulmonary venous hypertension + RV pressure overload; >90% obstructed

Age:

presentation in neonatal period

• intense cyanosis + respiratory distress (R-to-L shunt through ASD)

Prognosis:	death within a few days of life
Associated with:	asplenia syndrome (80%), polysplenia

• unique appearance of pulmonary edema + pulmonary venous congestion with normal-sized heart (DDx: hyaline membrane disease)

• low anterior indentation on barium-filled esophagus

Mixed Type of TAPVR (6%)

• = type IV

• = with various connections to R side of heart (6%)

Partial Anomalous Pulmonary Venous Return

• = PAPVR = only a portion of the pulmonary venous circulation connects to the LA

• May occur in isolation

N.B.:	venous return almost never obstructed!
Prevalence:	0.3 0.5% of patients with CHD
Age:	presentation later in life than TAPVR

May be associated with:

• Atrial septal defect (25%)

  • RUL pulmonary vein enters SVC/RA (66%)

    • 90% of patients with sinus venosus type ASD have PAPVR

    • 50% of patients with PAPVR have sinus venosus type ASD

    • RUL vein courses in a horizontal direction

  • LUL pulmonary vein enters brachiocephalic vein (33%)frequently associated with: ostium secundum type ASD (10 15%)

    • vertical mediastinal density lateral to aortic knob extending upward and medially with smooth curvilinear border (DDx: persistent left SVC)

• Hypogenetic lung as a component of congenital pulmonary venolobar syndrome

  • = Scimitar Syndrome

  • = lower part/all of the hypogenetic lung is drained by an anomalous vein

  • Anomalous vein drains into:

    • IVC below right hemidiaphragm (33%)

    • suprahepatic portion of IVC (22%)

    • hepatic veins

    • portal vein (11%)

    • azygos vein

    • coronary sinus

    • right atrium (22%)

    • left atrium = meandering pulmonary vein

      • Drainage into suprahepatic portion of IVC/right atrium may be a clue for interruption of intrahepatic portion of IVC!

  May be associated with:	systemic arterialization of the lung without sequestration
  Location:	almost exclusively on right side

  • tubular structure paralleling the right heart border in the configuration of a Turkish sword = scimitar (PA view)

  • shift of heart + mediastinum into right chest

• acyanotic

• ASD symptomatology

• radiographic findings similar to ASD

• anomalous course of draining vein

• enlargement of draining site: SVC, IVC, azygos vein

CECT:

• nodular/tubular opacity (= anomalous vein), which opacifies in phase with pulmonary vein

Aortic Aneurysm

Cause:

• Atherosclerosis (73 80 90%): descending aorta

• Traumatic (15 20%): following transection; descending aorta

• Congenital (2%): aortic sinus, post coarctation, ductus diverticulum

• Syphilis (19%): ascending aorta + arch

• Mycotic = bacterial dissection; anywhere

P.615




• Cystic media necrosis (Marfan/Ehlers-Danlos syndrome, annuloaortic ectasia): ascending aorta

• Inflammation of media + adventitia:

  • Takayasu arteritis, giant cell arteritis, relapsing polychondritis, rheumatic fever, rheumatoid arthritis, ankylosing spondylitis, Reiter syndrome, psoriasis, ulcerative colitis, systemic lupus erythematosus, scleroderma, Beh et disease, radiation

• Increased pressure:

  • systemic hypertension, aortic valve stenosis

• Abnormal volume load: severe aortic regurgitation

True Aneurysm

• = permanent dilatation of all layers of weakened but intact wall

False Aneurysm

• = focal perforation with all layers of wall disrupted; escaped blood contained by adventitia/perivascular connective tissue + organized blood

Fusiform Aneurysm (80%)

• = circumferential involvement

Saccular aneurysm

• = involvement of portion of wall

Abdominal Aortic Aneurysm (AAA)

• There is no consensus regarding the definition of an atherosclerotic AAA!

• = focal widening >3 cm (ultrasound literature); twice the size of normal aorta/>4 cm [Bergan, Ann Surg 1984]

• Normal size of abdominal aorta >50 years of age:

  • 12 19 mm in women; 14 21 mm in men

Prevalence:	1.4 8.2% in unselected population; in 6% >80 years of age; in 6 20% of patients with signs of atherosclerotic disease; M > F; Whites:Blacks = 3:1
Cause:	? genetic (10-fold increase in risk as first-degree relative of patient with AAA); structural defect of aortic wall caused by increased proteolysis; copper deficiency
Risk factors:	male sex, age >75 years, white race, prior vascular disease, hypertension, cigarette smoking, family history, hypercholesterolemia
Age:	>60 years; M:F = 5 9:1

Associated with:

• visceral + renal artery aneurysm (2%)

• isolated iliac + femoral artery aneurysm (16%):

• common iliac (89%), internal iliac (10%), external iliac (1%)

• stenosis/occlusion of celiac trunk/SMA (22%)

• stenosis of renal artery (22 30%)

• occlusion of inferior mesenteric artery (80%)

• occlusion of lumbar arteries (78%)

Growth rate of aneurysm of 3 6 cm in diameter:

• 0.39 cm/year

• asymptomatic (30%)

• abdominal mass (26%)

• abdominal pain (37%)

• Imaging should provide information about:

  • the proximal extent of the aneurysm, which determines the site of clamping of the aorta (origin of renal arteries)

  • the course of the left renal vein (retroaortic?)!

Location:

infrarenal (91 95%) with extension into iliac arteries (66 70%)

Plain film:

• mural calcification (75 86%)

US:

• >98 % accuracy in size measurement

NCCT:

• perianeurysmal fibrosis (10%), may cause ureteral obstruction

• crescent sign = peripheral high-attenuating crescent in aneurysm wall (= acute intramural hematoma) = sign of impending rupture

CECT:

• ruptured aneurysm

  • anterior displacement of kidney

  • extravasation of contrast material

  • fluid collection/hematoma within posterior pararenal + perirenal spaces

  • free intraperitoneal fluid

  • perirenal cobwebs

• contained leak

  • laminated mural calcification

  • periaortic mass of mixed/soft-tissue density

  • lateral draping of aneurysm around vertebral body

  • focal discontinuity of calcifications (unreliable)

  • indistinct aortic wall (unreliable)

Angio (AP + LAT filming):

• focally widened aortic lumen >3 cm

• apparent normal size of lumen secondary to mural thrombus (11%)

• mural clot (80%)

• slow antegrade flow of contrast medium

• Contained rupture = extraluminal hematoma/cavity

  • absent parenchymal stain = avascular halo

  • displacement + stretching of aortic branches

Cx:

• Rupture (25%)

  • into retroperitoneum: commonly on left

  • into GI tract: massive GI hemorrhage

  • into IVC: rapid cardiac decompensation

  Incidence:

  aneurysm <4 cm in 10%, 4 5 cm in 23%, 5 7 cm in 25%, 7 10 cm in 46%, >10 cm in 60%

  • sudden severe abdominal pain radiating into back

  • faintness, syncope, hypotension

  Prognosis:	64 94% die before reaching hospital
  Increased risk:	size >6 cm, growth >5 mm /6 months, pain + tenderness

  • The exact moment of rupture is unpredictable!

  • Cause of death in 1.3% of men >65 years!

• Peripheral embolization

• Infection

• Spontaneous occlusion of aorta

Prognosis:	17% 5-year survival without surgery, 50 60% 5-year survival with surgery
Rx:	surgery recommended if >5 cm in diameter; 4 5% surgical mortality for nonruptured, 30 80% for ruptured aneurysm

P.616

Postoperative Cx:

• Left colonic ischemia (1.6%) with 10% mortality

• Renal failure (14%)

• 0 8% mortality rate for elective surgery

Atherosclerotic Aneurysm

Incidence:	most common cause of aortic aneurysms; leading cause of thoracic aortic aneurysm
Histo:	diseased intima with secondary degeneration + fibrous replacement of media; ultimately wall of aneurysm composed of acellular + avascular connective tissue

Pathophysiology:

• progressive weakening of media results in vessel dilatation + increased tension of vessel wall (law of Laplace = tensile stress varies with product of blood pressure and radius of vessel); compromise of mural vascular nutrition (vasa vasorum) causes further degeneration + progressive dilatation

Age:

elderly; M > F

• asymptomatic (most)

• chest pain; symptoms related to compression of adjacent structures (dysphagia, hoarseness, lobar atelectasis, pneumonia, parenchymal hemorrhage, superior vena cava syndrome)

Location:	distal abdominal aorta (66%) > iliac a. > popliteal a. > common femoral a. > aortic + descending thoracic aorta > carotid a. > ascending aorta
Site:	(1) infrarenal aorta (associated with thoracic aneurysm in 29%) (2) descending thoracic aorta distal to left subclavian artery (3) thoracoabdominal

• fusiform (80%), saccular (20%)

• frequently contain calcified thrombus with irregular inner contour

Cx:

rupture (cause of death in 50%): usually unrestrained + fatal in thoracic location

Degenerative Aneurysm

• = medial degeneration

• Most common cause of aneurysm in ascending aorta

Cause:

(1) genetically transmitted metabolic disorder: Marfan syndrome, Ehlers-Danlos syndrome
(2) acquired: result of repetitive aortic injury + repair associated with aging

Inflammatory Aortic Aneurysm

• = defined as triad of

  • thickened wall of aneurysm

  • extensive perianeurysmal + retroperitoneal fibrosis

  • dense adhesions of adjacent abdominal organs

Frequency:	3-10% of all AAAs; M:f = 6:1 to 30:1
Mean age:	62-68 years

• abdominal/back pain

• weight loss + anorexia (20 41%)

• elevated ESR (40 88%)

• tender pulsatile abdominal mass (15 30%)

Comorbidities:	arterial hypertension (34 69%), arterial occlusive disease (10 47%), diabetes mellitus (3 13%), coronary artery disease (33 55%)
Size:	usually small at presentation because of early symptomatology

CT:

• rind of homogeneous soft-tissue density surrounding aorta anteriorly + laterally

• contrast enhancement (DDx from hematoma)

• entrapment of ureters (10 21%)

US:

• sonolucent halo around aorta

Cx:

enlargement + rupture (lower rate than in noninflammatory aneurysm)

Leaking Aortic Aneurysm

• acute chest pain

At risk for rupture:

symptomatic > asymptomatic aneurysm; mycotic aneurysm; thoracic aortic aneurysm > 6 cm

MR:

• irregular aneurysm wall

• extra-aortic blood

• pleural effusion containing high signal intensity on T1WI (methemoglobin)

• admixture of lower-intensity blood products + fat in mediastinum

Cx:

rupture into left pleural space (descending thoracic aorta); rupture into pericardium/ mediastinum (ascending thoracic aorta)

Mycotic Aneurysm

Incidence:

2.6% of all abdominal aneurysms

• PRIMARY MYCOTIC ANEURYSM (rare)

  • unassociated with any demonstrable intravascular inflammatory process

• SECONDARY MYCOTIC ANEURYSM

  • = aneurysm due to nonsyphilitic infection

  Predisposing factors:

  • IV drug abuse

  • Bacterial endocarditis (12%)

  • Immunocompromise (malignancy, alcoholism, steroids, chemotherapy, autoimmune disease, diabetes)

  • Atherosclerosis

  • Aortic trauma caused by accidents/aortic valve surgery/coronary artery bypass surgery/arterial catheterization

  Mechanism:

  • septicemia with abscess formation via vasa vasorum

  • septicemia with abscess formation via vessel lumen

  • direct extension of contiguous infection (of sternum/spine) weakening + destroying part of the aortic wall

  • preexisting intima laceration (trauma, atherosclerosis, coarctation)

  P.617

  
  

  Organism:	S. aureus (53%), Salmonella (33-50%), nonhemolytic Streptococcus, Pneumococcus, Gonococcus, Mycobacterium (contiguous spread from spine/lymph nodes)
  Histo:	loss of intima + destruction of internal elastic lamella; varying degrees of destruction of muscularis of media + adventitia

  • frequently insidious, fever (NO acute chest pain)

  • positive blood culture in 50%

Site:

ascending aorta near sinus of Valsalva > abdominal visceral artery > intracranial artery > lower/upper extremity artery

• true (majority)/false aneurysm

• saccular structure arising eccentrically from aortic wall with rapid enlargement

• interrupted ring of aortic wall calcification

• periaortic gas collection

• adjacent vertebral/sternal osteomyelitis

• adjacent reactive lymph node enlargement

Cx:	(1) Life-threatening rupture + hemorrhage (75%) (2) Uncontrolled sepsis if untreated
Rx:	surgery
Prognosis:	67% overall mortality

Syphilitic Aneurysm

Spectrum:

• Uncomplicated syphilitic aortitis

• Syphilitic aortic aneurysm (mostly saccular)

• Syphilitic aortic vasculitis (aortic regurgitation)

Incidence:	12% of patients with untreated syphilis
Onset:	10 30 years after initial spirochete infection
Histo:	chronic inflammation of aortic adventitia + media beginning at vasa vasorum + leading to obstruction of vasa vasorum followed by nutritional impairment of media + loss of elastic fibers + smooth muscle fibers

• positive venereal disease research laboratory (VDRL) test

• positive microhemagglutination assay Treponema pallidum (MHA-TP) test

Location:

ascending aorta (36%), aortic arch (34%), proximal descending aorta (25%), distal descending aorta (5%), aortic sinuses (<1 %)

• asymmetric enlargement of aortic sinuses (DDx to medial degeneration with symmetric enlargement)

• saccular (75%)/fusiform (25%) aneurysm

• pencil-thin dystrophic aortic wall calcification (up to 40%) most severe in ascending aorta, frequently obscured by thick coarse irregular calcifications of secondary atherosclerosis

Prognosis:

death in 2%, rupture in up to 40%; death within months of onset of symptoms if untreated

Thoracic Aortic Aneurysm

• Most common vascular cause of mediastinal mass!

  • 10% of mediastinal masses are of vascular origin!

• Average diameter of thoracic aorta (increasing with age):

  • aortic root: 3.6 cm

  • ascending aorta 1 cm proximal to arch: 3.5 cm

  • arch 2.9 cm

  • proximal descending aorta: 2.6 cm

  • middle descending aorta: 2.5 cm

  • distal descending aorta: 2.4 cm

Definitions:	diameter of 4 5 cm = aortic ectasia diameter of >5 cm = aortic aneurysm
Frequency:	25% of all aneurysms
Cause:	atherosclerosis (80%)
Associated with:	hypertension, coronary artery disease, abdominal aneurysm (30%)
Mean age:	65 years; M:F = 3:1

• substernal/back/shoulder pain (26%)

• SVC syndrome (venous compression)

• dysphagia (esophageal compression)

• stridor, dyspnea (tracheobronchial compression)

• hoarseness (recurrent laryngeal nerve compression)

Location:

arch > descending aorta

• mediastinal mass with proximity to aorta

• wide tortuous aorta

• curvilinear peripheral calcifications (75%)

• circumferential/crescentic mural thrombus

• Angio: may show normal caliber secondary to mural thrombus

Cx:

(1) Rupture into mediastinum, pericardium, either pleural sac, extrapleural space
high-attenuation fluid
(2) Aortobronchopulmonary fistula
consolidation of lung adjacent to aneurysm
Most aneurysms rupture when >10 cm in size

Prognosis:	1-year survival 57%, 3-year survival 26%, 5-year survival 19% (60% die from ruptured aneurysm, 40% die from other causes)
Rx:	operative repair considered if >6 cm in diameter
Surgical mortality:	10%

Traumatic Aortic Pseudoaneurysm

• = CHRONIC AORTIC PSEUDOANEURYSM

• 2nd most common form of thoracic aortic aneurysm

• Most common type occurring in young patients

Location vs Type of Thoracic Aortic Aneurysm
Location	Type
sinus of Valsalva	(1) congenital (2) infective endocarditis
effacement of sinotubular junction	(1) Marfan syndrome (2) idiopathic aortoannular ectasia (3) tertiary syphilis
aortic root	mycotic aneurysm
aortic root + ascending aorta	cystic medial necrosis (eg, Marfan syndrome)
ascending aorta	syphilis
aortic arch	atherosclerosis
ligamentum arteriosum	trauma
descending aorta	atherosclerosis

P.618

Incidence:

2.5% of patients who survive initial trauma of acute aortic transection

• usually calcified

• may contain thrombus

Cx:

(1) progressive enlargement
(2) rupture (even years after insult)

Complications of Endovascular Stent-Graft Repair

• Endoleak (2 45%)

  • = leakage into the aneurysm outside stent-graft

  • Type 1 = incomplete fixation of stent-graft to aortic wall at the proximal/distal attachment site

  • Type 2 = retrograde flow via parent artery (eg, lumbar/inferior mesenteric artery)

  • Type 3 = endograft defect with disruption of either metallic support/fabric

  Prognosis:

  enlargement of leak, aneurysm rupture

• Graft kinking

  Cause:	diminishing diameter of aneurysm after stent-graft implantation also decreases length of aneurysm
  Associated with:	distal migration of stent-graft

• Graft infection

  • interval development of perigraft soft-tissue attenuation/air

  Rx:

  antibiotics + total excision of infected graft

• Graft thrombosis (3 19%)

  • = intraluminal circular/semicircular thrombus

  Prognosis:

  spontaneous shrinkage, development of complete thrombosis

• Graft occlusion

• Shower embolism (4 17%)

  Cause:	mural thrombus dispersed by delivery system
  Prognosis:	perioperative death

• Colon necrosis

  Cause:

  occlusion of inferior mesenteric artery by stent-graft

• Aortic dissection

  Cause:

  retrograde injury by delivery system

Aortic Dissection

• = spontaneous longitudinal separation of aortic intima and adventitia by circulating blood having gained access to the media of the aortic wall splitting it in two

Path:

destruction of media leads to formation of a false channel:
(1) Transverse tear in weakened intima (95 97%)
The diagnosis relies primarily on visualization of an intimal flap + blood flow within a false lumen
(2) Primary hemorrhage into aortic wall WITHOUT intimal tear (3 5 13%) = INTRAMURAL AORTIC HEMATOMA see below

Pathogenesis:

• intimal tear results from combination of following factors:

• (a) media degeneration decreases cohesiveness within aortic wall

• (b) persistent aortic motion secondary to a beating heart stresses the aortic wall

• (c) hydrodynamic forces accentuated by hypertension

Incidence:	3:1,000 (more common than all ruptures of thoracic + abdominal aorta combined); 1:205 autopsies; 2,000 cases/year in USA
Peak age:	60 years (range 13 87 years); M:F = 3:1
Predisposed:	(cystic medial necrosis/disease of aortic wall)

• Starts in fusiform aneurysms in 28%

• Does not occur in aneurysms <5 cm in diameter

• 1. Hypertension (60 90%)

• 2. Marfan syndrome (16%)

• 3. Ehlers-Danlos syndrome

• 4. Relapsing polychondritis

• 5. Valvular aortic stenosis

• 6. Turner syndrome

• 7. Beh et disease

• 8. Coarctation NOT syphilis

• 9. Bicuspid aortic valve

• 10. S/P prosthetic valve

• 11. Trauma (rare)

• 12. Catheterization

• 13. Pregnancy

• 14. Aortitis (eg, SLE)

• 15. Cocaine abuse

• In women 50% of dissections occur during pregnancy!

• sharp tearing intractable anterior/posterior chest pain (75 95%) radiating to jaw, neck, low back (DDx: myocardial infarction)

• murmur bruit (65%) from aortic regurgitation

• asymmetric peripheral pulses + blood pressures (59%)

• absent femoral pulses (25%), reappearing after reentry

• pulse deficit: in up to 50% of type A dissection, in 16% of type B dissection

• hemodynamic shock (25%)

• neurologic deficits (25%): hemiplegia, paraparesis (due to compromise of anterior spinal artery of Adamkiewicz)

• persistent oliguria

• congestive heart failure (rare) due to acute aortic insufficiency

• recurrent arrhythmias/right bundle branch block

• signs of pericardial tamponade: clouded sensorium, extreme restlessness, dyspnea, distended neck veins

Aortic Dissection

Types:
DeBakey Classification:
Type I	(29 34%)	= ascending aorta + portion distal to arch
Type II	(12 21%)	= ascending aorta only
Type III	(50%)	= descending aorta only
subtype III A		= up to diaphragm
subtype III B		= below diaphragm
Stanford Classification:		(preferable as it effects treatment recommendations)
Type A		(60 70%) = ascending aorta arch in first 4 cm in 90%
Type B		(30 40%) = descending aorta only
mnemonic:		Affec aortaffects aortascending aorta and arch; B begins beyond brachiocephalic vessels; I = II + III

P.619

Clinical classification:

(1)

Acute aortic dissection: <2 weeks old
(2) Chronic aortic dissection: >2 weeks old

Flow velocities (average):

• 13.4 cm/sec in true lumen

• 3.1 cm/sec in false lumen

• retrograde flow more common in false lumen

Location of dissection (following helical flow pattern):

• on anterior + right lateral wall of ascending aorta just distal to aortic valve (65%)

• on superior + posterior wall of transverse aortic arch (10%)

• on posterior + left lateral wall of upper descending aorta distal to left subclavian artery (20%)

• more distal aorta (5%) usually terminating in left iliac artery (80%)/right iliac artery (10%) [involvement of left renal artery in 50%]

• An exit/distal tear/reentry occurs in 10%!

Atypical configurations of intimal flap:

• circumferential intimal flap due to dissection of entire intima

• filiform intimal flap creating an extremely narrow true lumen ( } ischemic complications)

• mural calcification of false lumen (in chronic dissection)

• three-channel aorta (= Mercedes-Benz sign) due to two false channels

• intimointimal intussusception

CXR (best assessment from comparison with serial films):

• normal CXR in 25%

• calcification sign = inward displacement of atherosclerotic plaque by >4-10 mm from outer aortic contour (7%), can only be applied to contour of descending aorta secondary to projection, may be misleading in presence of periaortic soft-tissue mass/hematoma

• disparity in size between ascending + descending aorta

• irregular wavy contour/indistinct outline of aorta

• widening of superior mediastinum to >8 cm due to hemorrhage/enlarging false channel (40-80%)

• cardiac enlargement (LV hypertrophy/hemopericardium)

• left pleural effusion (27%)

• atelectasis of lower lobe

• rightward displacement of trachea/endotracheal tube

ECHO:

• transesophageal echocardiography (tee): 95 100% sensitive + 77 97% specific

  • Ultrasound can be performed at bedside!

  False-positive (33%):

  reverberation artifacts from calcified aortic wall

• transthoracic US: 59 85% sensitive + 63 96% specific for type A dissection; poorer for type B

• intravascular in conjunction with aortography to differentiate true from false lumen

  • intimal flap (seen in more than one view)

  • pericardial fluid

  • aortic insufficiency

False-positives:

reverberation echoes from aneurysmal ascending aorta/calcified atheromatous plaque, postoperative periaortic hematoma

Angio (86 88% sensitive, 75 94% specific):

• Largely replaced by noninvasive cross-sectional imaging techniques

Superior to any other technique in demonstrating

• entry + reentry points (in 50%)

• branch vessel involvement + coronary

• aortic insufficiency

• visualization of intimal/medial flap radiolucency within opacified aorta

• double barrel aorta (87%) = opacification lumens

• abnormal catheter position outside anticipated aortic course

• compression of true lumen by false channel (72 85%)

• aortic valvular regurgitation (30%)

• increase in aortic wall thickness >6 10 mm

• obstruction of aortic branches: left renal artery (25 30%)

• ulcerlike projections caused by truncated branches

• slower blood flow in false lumen

False-negative:	complete thrombosis/slow blood flow of false channel (10%), intimal flap not tangential to x-ray beam
False-positive:	thickening of aortic wall due to aneurysm, aortitis, adjacent neoplasm/hemorrhage

CECT (87 100% sensitive, 87 100% specific):

• within 4 hours (if patient responds rapidly to medical Rx); detection as accurate as angio with single-level dynamic scanning

• crescentic high-attenuation clot within false lumen

• internally displaced intimal calcification (DDx: calcification of thrombus on luminal surface or within)

• intimal flap separating two aortic channels (may be seen without contrast in anemic patients)

• entry tear = most proximal split/discontinuity in intimal flap

False-negative:	inadequate contrast opacification, thrombosed lumen misinterpreted as aortic aneurysm with mural thrombus
False-positive:	perivenous streaks secondary to beam hardening + motion, cardiac/aortic motion artifacts, opacified normal sinus of Valsalva, normal pericardial recess mistaken for thrombus, mural thrombus in a fusiform aortic aneurysm, periaortic fibrosis, anemia with apparent high attenuation of aortic wall

MR (95 100% sensitive, 90 100% specific):

Advantage:	large field of view in any plane; contrast material not necessary
Disadvantage:	longer imaging time; difficulty monitoring acutely ill patients; image degradation from motion (uncooperative patient, atrial fibrillation)

P.620

SE images:

• intimal flap of medium intensity outlined by signal voids of rapidly flowing blood in true + false lumen

• intimal flap more difficult to detect in the presence of slow flow/thrombus (false lumen has intermediate intensity instead of flow void)

• cobwebs (25%) traversing the corners of the false lumen = bands of medial elastic lamellae spanning the junction of the dissecting septum with the outer wall of the false lumen

GRE images:

• lower-intensity intimal flap between high-intensity channels of flowing blood

• intermediate signal from thrombosed lumen

• aortic valve insufficiency = conical area of signal loss from aortic valve into LV during systole (2 to intravoxel dephasing caused by turbulence)

Cx:

(1) Retrograde dissection (in Stanford type A)
(a) aortic insufficiency
(b) occlusion of coronary artery (8%)
(c) internal rupture into RV, LA, vena cava, pulmonary artery producing large L-to-R shunt
(2) Occlusion/transient obstruction of major aortic branches (in up to 27%)
(a) static obstruction
flap enters branch-vessel origin
(b) dynamic obstruction = flap spares branch-vessel origin but covers it like a curtain
collapsed true lumen outlined by a C-shaped flap envelope which is concave toward false lumen (ischemic configuration)
(3) External rupture of aorta into pleural cavity/pericardial sac: 70% mortality (= most common cause of death within 24 hours)
(4) Development of aneurysm (15%) of the true/false lumen
Organs may receive their blood supply through either the true or false lumen or both!

Rx:

• Reducing peak systolic pressure to 120 70 mm Hg (adequate alone for type III = B, which rarely progresses proximally): death from rupture of aortic aneurysm in 46% of hypertensive + 17% of normotensive patients

  Survival rate:

  40 70% (with medical/surgical management)

• Immediate surgical graft reinforcement of aortic wall (Type I, II = A) preventing rupture + progressive aortic valve insufficiency

Nonsurgical survival rate:	<10%
Postsurgical mortality:	10 35%
Cx:	myocardial infarction, stroke, respiratory insufficiency, pulmonary embolism, aortic rupture, pseudoaneurysm, graft infection

Prognosis without Rx:

• immediate death (3%); death within: 1 day (20 30%), 1 week (50 62%), 3 weeks (60%), 1 month (75%), 3 months (80%), 1 year (80 95%)

Prognosis with Rx:

• 5 10% mortality rate following timely surgery; 40% 10-year survival rate after leaving hospital

DDx:

penetrating ulcer of thoracic aorta (= atherosclerotic lesion of mid-descending aorta with ulceration extending through intima into aortic media)

Intramural Aortic Hematoma (3 13%)

• = ATYPICAL AORTIC DISSECTION = IMH

• = aortic dissection without rupture of intima (? early stage/variant of aortic dissection)

Cause:	hemorrhage of vasa vasorum
Path:	clotted intramural blood within aortic media; NO/(?) slow flow within the false channel

• signs + symptoms + classification identical to classic dissection

• NO intimal flap

NECT (necessary):

• cuff/crescent of high attenuation

• displacement of intimal calcification

CECT:

• mural region of low attenuation with smooth border maintaining a constant circumferential relationship with aortic wall

MR:

• crescent-shaped eccentric wall thickening

Aortography:	not useful!
Cx:	ulcerlike projection with progression to open dissection/saccular or fusiform aneurysm
Rx:	(1) emergency surgical repair for type A hematoma (probably represents early stage with development of classic aortic dissection) (2) observation for type B hematoma (may heal completely)

DDx:

• Acutely thrombosed false lumen of dissection (tendency to spiral longitudinally around aorta)

• Atheromatous mural thrombus (irregular internal border)

• Focal periaortic soft-tissue mass (irregular external border)

  • idiopathic periaortic fibrosis

  • periaortic lymphoma

• Aortic motion artifact simulating type A IMH

Aortic Prosthetic Graft Infection

Incidence:

1.3 6% of prosthetic graft procedures

Classification:

• PERIGRAFT INFECTION (2 6%)

  • fever, chills, leukocytosis

  • groin swelling, heat, tenderness, pulsatile mass, draining sinus tract

• aortoenteric FISTULA (0.6 2%)

  • acute/chronic GI bleeding (may be occult)

  • sepsis

• may be temporally remote (up to 10 years): median time of 3 years to manifestation (70% occur after 1st year)

• intracavitary signs: malaise, back pain, fever, elevated sedimentation rate, hydronephrosis, ischemia from clotted graft

Normal postoperative course:

• ring of fat attenuation in early postoperative period <5 mm between aneurysm wall and graft

P.621




• Complete resolution of hematoma by 3 months

• Disappearance of ectopic gas complete by 4 7 weeks

CT (94% sensitive, 85% specific, 91% accurate):

• perigraft fluid

• perigraft soft-tissue attenuation with indistinctness of graft margins

• ectopic gas (fistulous communication with bowel/gas-producing organism)

• pseudoaneurysm (25%)

• focal bowel wall thickening (indicates fistula)

• >5 mm soft tissue between graft + surrounding wrap (beyond 7th postoperative week)

• focal discontinuity of calcified aneurysmal wrap

False positives:

• perigraft hematoma in early postoperative period, pseudoaneurysm (in 15 20%)

NUC:

• uptake of Tc-99m hexametazine labeled leukocytes (drawbacks: not performed quickly, hepatobiliary excretion)

Prognosis:	17 75% mortality; 30 50% morbidity
Dx:	positive culture from needle aspirate (incubation period should be up to 14 days as organisms may be slow-growing)

Aortic Regurgitation

• = AORTIC INSUFFICIENCY

Cause:

• INTRINSIC AORTIC VALVE DISEASE

  • Congenital bicuspid valve

  • Rheumatic endocarditis

  • Bacterial endocarditis (perforation/prolapse of cusp)

  • Myxomatous valve associated with cystic medial necrosis

  • Aortic valve prolapse

  • Prosthetic valve: mechanical break, thrombosis, paravalvular leak

• PRIMARY DISEASE OF ASCENDING AORTA

  • Dilatation of aortic annulus

    • Syphilitic aortitis

    • Rheumatoid arthritis

    • Rheumatoid variants:

      • Ankylosing spondylitis (5 10%)

      • Reiter disease

      • Psoriatic arthritis

    • Relapsing polychondritis

    • Familial connective tissue disease:

      mnemonic:

      HOME

      • Homocystinuria

      • Osteogenesis imperfecta

      • Marfan syndrome

      • Ehlers-Danlos syndrome

  • Laceration = aortic dissection

    • Deceleration trauma

    • Hypertension

Pathogenesis:

progressive enlargement of diastolic + systolic LV dimensions result in increase in myocardial fiber length + increase in stroke volume; decompensation occurs if critical limit of fiber length is reached

• water-hammer pulse = twin-peaked pulse

• systolic ejection murmur + high-pitched diastolic murmur

• Austin Flint murmur = soft mid-diastolic or presystolic bruit

• LV enlargement (cardiothoracic ratio >0.55) + initially normal pulmonary vascularity (DDx: congestive cardiomyopathy, pericardial effusion)

• normal aorta (in intrinsic valve disease)

• dilatation of aorta (in systemic disease):

  • calcification of ascending aorta (in aortic wall disease)

  • enlarged aortic arch + tortuous descending aorta

• increased pulsations along entire aorta

ECHO:

• aortic root dilatation

• high frequency flutter of aML (occasionally pML) during first 2/3 of diastole (CHARACTERISTIC)

• high frequency diastolic flutter of IVS (uncommon)

• diastolic flutter of aortic valve (SPECIFIC, but rare)

• premature aortic valve opening (high diastolic LV pressure)

• decreased MV opening (aML pushed posteriorly by regurgitant aortic jet)

• premature closure of mitral valve (high diastolic LV pressure produces MV closure before beginning of systole in severe acute aortic insufficiency)

• LV dilatation + large amplitude of LV wall motion (volume overload, increased ejection fraction):

End-systolic LV diameter	Action
<50 mm	yearly follow-up
50 54 mm	4- to 6-month follow-up
>55 mm	valve replacement

Doppler:

• slope of peak diastolic to end-diastolic velocity decrease >3 m/sec² in severe aortic regurgitation

• area of color Doppler regurgitant flow

• ratio of width of regurgitant beam to width of aortic root is good predictor of severity (color Doppler)

Aortic rupture

• = blood leakage through aortic wall

• 1. Spontaneous rupture of aortic aneurysm

  Pathogenesis:

  small clefts occur at a fragile site within inner thrombus gradually expanding to outer layer of thrombus with gradual seepage of flowing blood into mural thrombus and aneurysmal wall

CT:

• high-attenuation crescent sign (71%)

• 2. Spontaneous rupture of descending thoracic aorta

  Predisposed:	hypertension and atherosclerosis, NO preformed aneurysm!
  Pathogenesis:	pressure atrophy of media due to overlying intimal atheromatous plaque causing localized ballooning of aortic wall prior to perforation

• 3. Traumatic rupture/transection of thoracic aorta

  Cause:	blunt trauma to thoracic aorta
  see	BLUNT TRAUMA TO THORACIC AORTA

Aortic Stenosis

• Aortic valve area decreased to <0.8 cm² = 0.4 cm²/m² BSA (normal 2.5 3.5 cm²)

P.622

• ACQUIRED AORTIC STENOSIS

  • Rheumatic valvulitis (almost invariably associated with mitral valve disease)

  • Fibrocalcific senile aortic stenosis (degenerative)

• CONGENITAL AORTIC STENOSIS (most common)

  • = most frequent CHD associated with IUGR

  • 1. Subvalvular AS (15 30%)

  • 2. Valvular AS (60 70%): degeneration of bicuspid valve most common cause

  • 3. Supravalvular AS (rare)

Pathogenesis:

increased gradient across valve produces LV hypertrophy and diminished LV compliance; increased muscle mass may outstrip coronary blood supply (subendocardial myocardial ischemia with angina); LV decompensation leads to LV dilatation + pulmonary venous congestion

• asymptomatic for many years

• angina, syncope, heart failure

• systolic murmur

• carotid pulsus parvus et tardus

• diminished aortic component of 2nd heart sound

• sudden death in severe stenosis (20%) after exercise (diminished flow in coronary arteries causes ventricular dysrhythmias + fibrillation)

• poststenotic dilatation of ascending aorta (in 90% of acquired, in 70% of congenital AS)

• normal-sized/enlarged LV (small LV chamber with thick walls)

• @ in adults >30 years

  • calcification of aortic valve (best seen on RAO); indicates gradient >50 mm Hg

  • discrete enlargement of ascending aorta (NO correlation with severity of stenosis)

  • calcification of mitral annulus

  • left ventricular configuration = concavity along mid left lateral heart border + increased convexity along lower left lateral heart border

• @ in children/young adults

  • prominent ascending aorta

  • left ventricular heart configuration

• @ in infancy:

  • left ventricular stress syndrome

ECHO:

• thickened + calcified aortic valve with multiple dense cusp echoes throughout cardiac cycle (right > noncoronary > left coronary cusp)

• decreased separation of leaflets in systole with reduced opening orifice (13 14 mm = mild AS;

• 8 12 mm = moderate AS; <8 mm = severe AS)

• doming in systole

• dilated aortic root

• increased thickness of LV wall (= concentric LV hypertrophy)

• hyperdynamic contraction of LV (in compensated state)

• decreased mitral EF slope (reduced LV compliance)

• LA enlargement

• increased aortic valve gradient (Doppler)

• decreased aortic valve area (unreliable)

DDx:	calcification of aortic annulus in elderly/calcified coronary artery ostium (thickened cusp echoes only in diastole)
Prognosis:	depends on symptomatology (angina, syncope, CHF)

Subvalvular Aortic Stenosis

• = SUBAORTIC STENOSIS

• (a) Anatomic/fixed subaortic stenosis

  Associated with:

  cardiac defects in 50% (usually VSD)

  Type I	: thin 1 2-mm membranous diaphragmatic stenosis, usually located within 2 cm or less of valve annulus
  Type II:	thick collarlike stenosis
  Type III	: irregular fibromuscular stenosis
  Type IV	: tunnel subaortic stenosis = fixed tunnel-like narrowing of LVOT = excessive thickening of only upper ventricular septum with normal mitral valve motion

• (b) Functional/dynamic subaortic stenosis

  • Asymmetric septal hypertrophy (ASH)

  • Idiopathic hypertrophic subaortic stenosis (IHSS)

  • Hypertrophic obstructive cardiomyopathy (HOCM) may occur in infants of diabetic mothers

• no dilatation of ascending aorta

• asymmetrically thicker ventricular septum than free wall of LV (95%)

• normal/small left + right ventricular cavities (95%)

• lucent subaortic filling defect in systole

• focal convexity of left upper-mid cardiac margin = anterior aspect of ventricular septum (rare)

valvular Aortic stenoses

	Congenital	Rheumatic	Degenerative
Clinically apparent	<30 years	30-60 years	>65 years
Valve calcifications
first appearance	25 years	47 years	54 years
pattern	nodular/bicuspid	nodular	nodular/tricuspid
on CXR	>90% (40-65 years)	<10%	>90% (>65 years)
Aortic ectasia	ascending Ao	ascending Ao	entire Ao

ECHO:

• coarse systolic flutter of valve cusps

P.623




• opening of leaflets followed by rapid inward move in mid systole, leaflets may remain in partially closed position through latter portion of systole (to appose borders of the flow jet)

• systolic anterior motion of mitral valve

Cx:

mitral regurgitation (secondary to abnormal position of anterolateral papillary muscle preventing complete closure of MV in systole)

Valvular Aortic Stenosis

• = fusion of commissures between cusps

Degree:

mild: >0.7 cm²; moderate: 0.5 0.7 cm²; severe: <0.5 cm²

Congenital types:

• (a) bicuspid/unicuspid (in 95%): in 1 2% of population; M > F; commonly associated with coarctation of the aorta

• (b) tricuspid (5%)

• (c) dysplastic thickened aortic cusps

• valvular calcifications (in 60% of patients >24 years of age)

• @ IN INFANT with critical aortic stenosis:

  • intractable CHF in first days/weeks of life with severe dyspnea

  • may simulate neonatal sepsis

    Associated with:

    L-to-R shunts (ASD, VSD)

  • marked cardiomegaly (thickened wall of LV)

  • pulmonary venous hypertension

  • decreased ejection fraction

  • doming of thickened valve cusps

  • dilated ascending aorta

  Rx:

  emergency surgical dilatation

• @ IN CHILD:

  • asymptomatic until late in life

  • normal pulmonary vascularity

  • LV configuration with normal size of heart

  • large posterior noncoronary cusp, smaller fused right + left cusps

  • doming of thickened valve cusps

  • eccentric jet of contrast

  • poststenotic dilatation of ascending aorta

ECHO:

• increase in echoes from thickened deformed leaflets (maximal during diastole)

• decrease in leaflet separation

Supravalvular Aortic Stenosis

Types:

• localized hourglass narrowing just above aortic sinuses

• discrete fibrous membrane above sinuses of Valsalva

• diffuse tubular hypoplasia of ascending aorta + branching arteries

Associated with:

peripheral PS, valvular + discrete subvalvular AS, Marfan syndrome, Williams syndrome, infantile hypercalcemia syndrome

• small ascending thoracic aorta

• dilatation + tortuosity of coronary arteries (may undergo early atherosclerotic degeneration secondary to high pressure)

ECHO:

• narrowing of supravalvular aortic area (normal root diameter: 20 37 mm)

• normal movement of cusps

Aortopulmonic Window

• = defect in septation process characterized by large round/oval communication between left wall of ascending aorta + right wall of pulmonary trunk

• clinically resembles PDA

CXR:

• shunt vascularity

• cardiomegaly (LA + LV enlarged)

• diminutive aortic knob

• prominent pulmonary trunk

Angio (left ventriculogram/aortogram in AP/LAO projection):

• defect several mm above aortic valve

• pulmonary valve identified (DDx to truncus arteriosus)

Arteriosclerosis Obliterans

• = ASO = HARDENING OF THE ARTERIES

Prevalence:	2.4 million people in USA; in 1978 12% of autopsies had ASO as leading cause of death (excluding MI)
Etiology:	unknown

Contributing factors:

• aging, diabetes (16 44%), hypertension, atherosclerosis

Effect of hyperlipidemia:

• high-density lipoproteins (HDL) have a protective effect: carry 25% of blood cholesterol

• low-density lipoproteins (LDL): carry 60% of blood cholesterol

Histo:	deposition of lipids, blood products, carbohydrates, begins as disruption of intimal surface; fatty streaks (as early as childhood); fibrous plaques (as early as 3rd decade); thrombosis, ulceration, calcification, aneurysm
Age:	50 70 years; M > F (after menopause)

Clinical classification:

• Intermittent claudication = ischemic symptoms with exercise: calf, thigh, hip, buttock

• Ischemic symptoms at rest (indicative of multisegment disease)

• cramping/burning/aching pain

• cold extremity

• paresthesia

• trophic changes: hair loss, thickened nails

• ulcer, gangrene

• decreased/absent pulses

Location:

medium + large arteries; frequently at bifurcations; most frequent:

• superficial femoral artery in adductor canal (diabetics + nondiabetics)

• aortoiliac segment (nondiabetics)

• tibioperoneal trunk (diabetics)

Prognosis:

accelerated by diabetes (34% will require amputation), hypertension, lipoprotein abnormalities, heart disease (decreased cardiac output resulting in increased blood viscosity from polycythemia), chronic addiction to tobacco (11.4% will require amputation), intermittent claudication (5 7% require amputation if nondiabetic = 1 2% per year), ischemic ulcer/rest pain (19.6% require amputation)

P.624

Atrial Septal Defect

• Most common congenital cardiac defect after bicuspid aortic valve!

Incidence:	8 10 14% of all CHD; M:F = 1:3
Age:	presentation frequently > age 40 secondary to benign course (a) mildly symptomatic (60%): dyspnea, fatigue, palpitations (b) severely symptomatic (30%): cyanosis, heart failure

Embryology:

• Septum primum = at 4th week membrane grows from dorsal atrial wall toward endocardial cushions

• Ostium primum = temporary orifice between septum primum + endocardial cushions close to AV valves; it becomes obliterated by 5th week

• Ostium secundum = multiple small coalescing fenestrations in center of septum primum

• Septum secundum = membrane developing on right side of septum primum + covering part of ostium secundum

• Foramen ovale = orifice limited by septum secundum + septum primum

• Foramen ovale flap = lower edge of septum primum (patent in 6%, probe-patent in 25%); not considered an ASD

• OSTIUM SECUNDUM ASD (70%)

  • = exaggerated resorptive process of septum primum leads to absence/fenestration of the foramen ovale flap (Chiari network)

  Location:	in the center of the atrial chamber at fossa ovalis
  Size:	large defect of 1 3 cm in diameter

  May be associated with:

  • prolapsing mitral valve (20 30%), pulmonary valve stenosis, tricuspid atresia, TAPVR, hypoplastic left heart, interrupted aortic arch

• OSTIUM PRIMUM ASD (20%)

  • = defect of atrioventricular endocardial cushion

  Location:

  lower end of septum inferior to fossa ovalis (at outlet portion of atrial septum) adjacent to atrioventricular valves

  Almost always associated with:

  • cleft mitral valve, common atrioventricular canal complex, Down syndrome, anterior fascicular block

• SINUS VENOSUS ASD (10%)

  • = defect of the superior inlet portion of the atrial septum

  Location:	superior to fossa ovalis near entrance of superior vena cava (SVC straddles ASD)
  Associated with:	partial anomalous pulmonary venous return in 90% (RUL pulmonary veins connect to SVC/right atrium), Holt-Oram syndrome, Ellis-van Creveld syndrome

• Coronary Sinus Defect

  • normal coronary sinus typically absent (unroofed), persistent SVC drains directly into LA

• Lutembacher SYNDROME = ASD + mitral stenosis

  Hemodynamics:

  • no hemodynamic perturbance in the fetus; after birth physiologic increase in LA pressure + greater compliance of RA and RV create a L-to-R shunt (shunt volume may be 3 4 times that of systemic blood flow); volume overload of RV is well tolerated in childhood, leads to RV dilatation, right heart failure; diastolic pressure differences in atria determine direction of shunt; pulmonary pressure remains normal for decades; after 40 years of age onset of pulmonary hypertension causes increased R-to-L shunting (Eisenmenger syndrome); pulmonary hypertension in young adulthood (6%)

• repeated respiratory infections

• feeding difficulties

• atrial arrhythmias: atrial flutter + atrial fibrillation increases with age

• thromboembolism

• asymptomatic; occasionally discovered by routine CXR

• right ventricular heave

• fixed splitting of second heart sound with accentuation of pulmonary component (ejection murmur grade II/VI) heard at 2nd left intercostal space along PA

• ECG: right axis deviation + some degree of right bundle branch block

• exertional dyspnea after development of pulmonary arterial hypertension (= Eisenmenger syndrome)

• cyanosis may occur (shunt reversal to R-to-L shunt), typically during 3rd 4th decade

• right heart failure in patients >40 years

CXR:

• normal (if shunt <2 systemic blood flow)

• overcirculation = increase in pulmonary blood flow (if pulmonary-to-systemic blood flow 2:1)

• cardiomegaly:

  • heart small compared with pulmonary vascularity = closing shunt

  • heart large compared with pulmonary vascularity = intercurrent myocardial/aortic disease

• loss of visualization of SVC (= clockwise rotation of heart due to RV hypertrophy)

• small appearing aorta with normal aortic knob

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• normal size of LA after shunt reversal (due to immediate decompression into RA) in Eisenmenger syndrome:

  • enlargement of PA + central pulmonary arteries

  • RV enlargement

• hilar dance = increased pulsations of central pulmonary arteries (DDx: other L-to-R shunts)

ECHO:

• paradoxical interventricular septal motion (due to volume overload of RV)

• direct visualization of ASD (= lack of echoes of atrial septum) in subcostal view

• diastolic blood flow from interatrial septum crossing RA + tricuspid valve observed by color Doppler

MR:

• discrete area of interruption of the normal intermediate-intensity interatrial septum

  CAVE:

  normal thinning of fossa ovalis can cause drop-out of atrial signal

• area of signal loss from atrial septum into RA (due to turbulent jet) on GRE

• ratio of stroke volumes in aorta to PA (measurement of flow volume on cine phase-contrast images)

Angio:

• RA fills with contrast shortly after LA is opacified (on levophase of pulmonary angio in AP or LAO projection)

• injection into RUL pulmonary vein to visualize exact size + location of ASD (LAO 45 + C-C 45 )

Prognosis:

• Mortality: 0.6% in 1st decade; 0.7% in 2nd decade; 2.7% in 3rd decade; 4.5% in 4th decade; 5.4% in 5th decade; 7.5% in 6th decade; median age of death is 37 years

• Spontaneous closure: 22% in infants <1 year; 33% between ages 1 and 2 years; 3% in children >4 years

Cx:	(1) Tricuspid insufficiency (secondary to dilatation of AV ring) (2) Mitral valve prolapse (3) Atrial fibrillation (in 20% 1st presenting symptom in patients > age 40)
Rx:	(if vascular changes still reversible = resistance of pulmonary-to-systemic system 0.7); 1% surgical mortality 1. Surgical patch closure 2. Rashkind foam + stainless steel prosthesis

Atrial Septal Defects

Normal Newborn Heart

Ostium Secundum Defect

Sinus Venosus Defect

Ostium Primum Defect

Beneficial ASD

• = secundum type ASD serves an essential compensatory function in:

• 1. Tricuspid atresia

  • RA blood reaches pulmonary vessels via ASD + PDA; improvement through Rashkind procedure

• 2. TAPVR

  • significant shunt volume only available through ASD (VSD/PDA much less reliable)

• 3. Hypoplastic left heart

  • systemic circulation maintained via RV with oxygenated blood from LA through ASD into RA

Azygos Continuation of IVC

• = INTERRUPTED IVC WITH AZYGOS/HEMIAZYGOS CONTINUATION = ABSENCE OF THE HEPATIC SEGMENT OF THE IVC WITH AZYGOS CONTINUATION

Prevalence:	0.6%
Etiology:	formation failure of right subcardinal-hepatic anastomosis with atrophy of right subcardinal vein + shunting of blood from supracardinal-subcardinal anastomosis to cranial portion of supracardinal vein (= retrocrural azygos vein)

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May be associated with:

• polysplenia syndrome (more common), asplenia syndrome (rare), indeterminate situs (= situs ambiguus), persistent left SVC, dextrocardia, transposed abdominal viscera, duplicated IVC, retroaortic left renal vein, congenital pulmonary venolobar syndrome

• absence of hepatic infrahepatic IVC:

  • drainage of hepatic veins into right atrium via supra-/posthepatic segment of IVC (N.B.: IVC shadow present on LAT CXR!)

• drainage of iliac + renal veins via azygos/hemiazygos vein:

  • right renal artery crosses anterior to IVC on US

• both gonadal veins drain into ipsilateral renal vein (since postcardinal-subcardinal anastomosis does not contribute to formation of IVC)

CXR:

• enlargement of azygos arch to >7 mm

• widening of right paraspinal stripe contiguous with azygos arch (= enlarged paraspinal + retrocrural azygos veins)

• widening of left paraspinal stripe (= enlarged hemiazygos vein)

DDx:

right-sided paratracheal mass with retrocrural adenopathy

Bacterial Endocarditis

Predisposed:

• Rheumatic valve disease

• Mitral valve prolapse with mitral regurgitation

• Aortic stenosis, mitral stenosis, aortic regurgitation, mitral regurgitation

• Most CHD (VSD, TOF) except ostium secundum ASD

• Previous endocarditis

• Drug addicts:

  • endocarditis of tricuspid valve causes multiple septic pulmonary emboli

• Bicuspid aortic valve:

  • responsible for 50% of aortic valvular bacterial endocarditis

• Prosthetic valve:

  • 4% incidence of bacterial endocarditis

  • exaggerated valve motion (= disintegration of suture line + regurgitation)

Valve Vegetations

ECHO:

• usually discrete focal echodensities with sharp edges; may show fuzzy/shaggy nonuniform thickening of cusps (vegetations) in systole + diastole

• may appear as shaggy echoes that prolapse when the valve is closed (DDx to mitral valve prolapse)

Buerger Disease

• = THROMBANGITIS OBLITERANS

• = idiopathic recurrent segmental obliterative vasculitis of small + medium-sized peripheral arteries + veins (panangitis)

Incidence:	<1% of all chronic vascular diseases; more common in Israel, Orient, India
Etiology:	unknown

Histo:

• acute stage: multiple microabscesses within fresh/organizing thrombus; all layers of vessel wall inflamed but intact; internal elastic lamina may be damaged; multinucleated giant cells within microabscesses (PATHOGNOMONIC)

• subacute stage: thrombus organization with little residual inflammation

• chronic stage: lumen filled with organized recanalized thrombus, fibrosis of adventitia binds together artery, vein, and nerve

Associated with:

cigarette smoking (95%)

• instep claudication distal ulceration (symptoms abate on cessation of smoking + return on its resumption)

• Raynaud phenomenon (33%)

Location:	legs (80%), arms (10 20%)
Site:	starts in palmar + plantar vessels with proximal progression

• superficial + deep migratory thrombophlebitis (20 33%)

• arterial occlusions, tapered narrowing of arteries

• abundant corkscrew-shaped collaterals

• direct collateral following the path of the original artery (Martorell sign) in 80%

• skip lesions = multiple segments involved with portions of arterial wall remaining unaffected

• absence of generalized arteriosclerosis/arterial calcifications (90%)

Cardiac arrest

• = sudden cessation of cardiac pump function

CT:

• layering of static blood within heart + great vessels

• hematocrit effect = sedimentation of RBCs

• good depiction of cardiac anatomy (due to cessation of cardiac motion)

CECT:

• contrast pooling in dependent portion of venous system (right atrium, hepatic veins)

• no contrast in pulmonary artery + left heart structures

Rx:

prompt cardiopulmonary resuscitation

Cardiac Fibroma

• = FIBROMATOSIS = FIBROUS HAMARTOMA

  • = FIBROELASTIC HAMARTOMA

• = congenital neoplasm/hamartoma of the heart

Incidence:	100 cases reported; 2nd most common benign cardiac neoplasm of childhood (after rhabdomyoma)
Age:	0 56 years (mean age, 13 years); 33% in children <1 year of age/in utero; 15% in adolescents + adults
Increased prevalence in:	Gorlin (= basal cell nevus) syndrome

• heart failure, cardiac murmur (33%), arrhythmia

• NO embolism; asymptomatic (33%)

Path:	2 10-cm large single round bulging well-circumscribed tumor within ventricular myocardium; foci of calcification/ossification (50%)
Histo:	collection of fibroblasts interspersed among large amounts of collagen; numerous elastic fibers (>50%); NO foci of cystic change/hemorrhage/necrosis
Location:	ventricular septum > left ventricular free wall

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• cardiomegaly

• focal cardiac bulge (with tumor in free ventricular wall)

• pericardial effusion

ECHO:

• noncontractile echogenic heterogeneous solid mass:

  • mean diameter >5 cm; may obliterate cardiac chamber

  • multifocal dystrophic central tumor calcifications

• affected myocardium hypokinetic

DDx:

focal hypertrophic cardiomyopathy, hypertrophy of ventricular septum

CT:

• homogeneous mural mass of soft-issue attenuation

• sharply marginated/infiltrative

• calcifications (25%)

• variable enhancement

MR:

• iso-/hyperintense homogeneous discrete mural mass/myocardial thickening on T1WI

• hypointense on T2WI

• no/little hetero- or homogeneous enhancement

Prognosis:

• sudden death (due to invasion/compression of cardiac conduction system resulting in arrhythmia)

  • 2nd most common primary cardiac tumor associated with sudden death (after endodermal heterotopia of AV node)

• may remain stable in size for years/regress

Rx:	surgical excision/partial resection
DDx in infants:	rhabdomyoma (multiple masses)
DDx in children:	rhabdomyosarcoma (no calcification, cystic or necrotic tumor, invasion of pulmonary veins or pericardial space)

Cardiac Hemangioma

• = rare benign vascular tumor of the heart

Prevalence:	5 10% of benign cardiac tumors
Association:	Kasabach-Merritt syndrome (multiple systemic hemangiomas, recurrent thrombocytopenia, consumptive coagulopathy)
Path:	predominantly intramural spongy mass/well-circumscribed endocardial-based soft mass growing into pericardial space; may contain fat
Histo:	capillary (= smaller capillary-like vessels); cavernous (= multiple thin-walled dilated vessels); arteriovenous (= thick-walled dysplastic arteries + veins + capillaries)

• asymptomatic

• dyspnea on exertion, chest pain, right-sided CHF

• arrhythmia, syncope, pericarditis, sudden death

• pericardial effusion

US:

• hyperechoic mass

CT:

• heterogeneous intensely enhancing mass

MR:

• intermediate intensity on T1WI + hyperintense on T2WI

Angio:

• vascular blush in capillary + arteriovenous type

• no enhancement for cavernous type

Prognosis:	spontaneous regression possible
Rx:	surgical resection (for symptomatic lesion)

Cardiac Lipoma

• = very rare benign neoplasm

Incidence:	60 reported cases
Age:	typically in adults

• mostly symptomatic

• dyspnea (in intracavitary lipoma secondary to blood flow obstruction, in pericardial lipoma secondary to displacement of lung)

• arrhythmia (involvement of conduction system)

Path:	encapsulated spherical/elliptical solitary mass, often very large (up to 4,800 g) by the time the come to clinical attention; multiple lipomas in CHD, tuberous sclerosis
Histo:	mature adipocytes surrounded by capsule

Location:

• broad-based from epicardial surface growing into pericardial space

• broad-based from endocardial surface growing into cardiac chamber

• interatrial septum

• cardiomegaly, globular-shaped heart

• echogenic/hypoechoic broad-based nonmobile mass

• round mass with smooth contour

• homogeneous mass of -50 HU in cardiac chamber/pericardial space

• homogeneous mass of increased signal intensity a few thin septations on T1WI:

  • decreasing intensity with fat saturation

• no enhancement

Rx:	surgical resection
DDx:	lipomatous hypertrophy of interatrial septum (infiltrative, at level of fossa ovalis with sparing of fossa ovalis, >2 cm thick in transverse dimension, composed of brown fat, not a true neoplasm, associated with advanced age + obesity)

Cardiac Paraganglioma

• = extremely rare, usually benign sporadic neoplasm arising from intrinsic cardiac sympathetic paraganglial (chromaffin) cells

Incidence:	<50 cases
Age:	18-85 (mean, 40) years

• catecholamine-producing tumor (in the majority):

  • headache, arterial hypertension, palpitations, flushing

  • elevated levels of urinary norepinephrine, vanillylmandelic acid, total metanephrine

  • elevated levels of plasma norepinephrine, epinephrine

Associated with:

• additional paragangliomas (in 20%) in carotid body, adrenal gland, bladder, paraaortic

• metastases to bone (in 5%)

Path:	2-14 cm large encapsulated/poorly circumscribed and infiltrative highly vascular mass; necrotic in 60%
Histo:	monomorphic tumor composed of nests of paraganglial cells (= Zellballen ) surrounded by sustentacular cells
Location:	posterior wall of left atrium > roof of left atrium > atrial cavity > interatrial septum > ventricle
Site:	epicardial surface of the base of the heart with tendency to involve coronary arteries

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CXR:

• middle mediastinal mass splaying carina simulating left atrial enlargement (for typically located tumor)

ECHO:

• large echogenic left atrial mass

• compression of SVC, encasement of coronary aa.

DDx:

myxoma (broad base of attachment, softer)

NUC (I-131 or I-123 MIBG):

• for total body imaging with a sensitivity of 90%

NECT:

• circumscribed/ill-defined heterogeneous mass:

  • hypoattenuating

  • isoattenuating to cardiac structures (may be missed)

• tumor calcifications

• extracardiac extension

CECT:

• Premedicate patient with alpha- and beta-blockers as contrast material can trigger a hypertensive crisis!

• markedly enhancing mass adherent to/involving left atrium/anterior to aortic root

• central area of low attenuation (in 50%) from necrosis

MR:

• mass iso-/hypointense to myocardium on T1WI

• very hyperintense mass on T2WI

• intense often heterogeneous enhancement

Cardiac Sarcomas

• Majority of primary malignant cardiac neoplasms!

• 2nd most common primary cardiac neoplasm

Mean age:

41 years; extremely rare in infants + children

• right-sided heart inflow obstruction

  • 1. Angiosarcoma (37%): tumor in right atrium

• mitral valve obstruction (tumor in left atrium)

  • 2. Undifferentiated sarcoma (24%)

  • 3. Malignant fibrous histiocytoma (11 24%)

  • 4. Leiomyosarcoma (8 9%): tends to invade pulmonary veins + mitral valve

    Age:

    5 10 years earlier than other sarcomas

  • 5. Primary cardiac osteogenic sarcoma (3 9%)

DDx:

myxoma (at fossa ovalis)

• dyspnea, pericardial tamponade, arrhythmia, syncope, peripheral edema, sudden death

• embolic phenomena, chest pain, pneumonia, fever

• cardiomegaly

• CHF

• pleural effusion, pericardial effusion

• focal cardiac mass

• pulmonary consolidation

Metastatic to:	lung, lymph nodes, bone, liver, brain, bowel, spleen, adrenal gland, pleura, diaphragm, kidney, thyroid, skin
Prognosis:	mean survival of 3 month to 1 year

Angiosarcoma

Frequency:	most common cardiac sarcoma
Age:	typically in middle-aged men
Path:	frequently hemorrhagic + necrotic mass, often adherent to pericardium
Histo:	endothelial cells lining ill-defined vascular spaces

• right-sided heart failure, tamponade

• fever, weight loss

• bloody fluid on pericardiocentesis (rarely with malignant cells)

Metastases at presentation:	in 66 89%
Location:	right atrial free wall + involvement of pericardium (80%)

• well-defined mass protruding into a cardiac chamber

  • usually originating from right atrium with sparing of atrial septum

  • areas of central necrosis communicating with cardiac chamber

  • low-attenuation mass on CT

  • heterogeneous contrast enhancement

  • heterogeneous MR signal:

    • cauliflower appearance = local nodular hyperintense areas interspersed within areas of intermediate signal intensity on T1WI + T2WI

• diffusely infiltrative mass extending along epicardial surface

  • obliterated pericardial space (hemorrhage + necrotic tumor debris)

  • sunray appearance = linear contrast enhancement along vascular lakes on MR

Prognosis:

12 30 months survival

Undifferentiated Sarcoma

• = PLEOMORPHIC SARCOMA = ROUND CELL SARCOMA = SPINDLE CELL SARCOMA

Age:

45 years (neonates to elderly)

• pulmonary congestion

Location:

left atrium

• large irregular hypodense intracavitary mass

• polypoid mass isointense to myocardium

• thickening/irregularity of myocardium (due to tumor infiltration)

• tendency to involve valves

• hemorrhagic mass replacing the pericardium (similar to angiosarcoma)

Cardiac Tamponade

• = significant compression of heart by fluid contained within pericardial sac resulting in impaired diastolic filling of ventricles

Cause:

see PERICARDIAL EFFUSION

• tachycardia

• pulsus paradoxus = exaggeration of normal pattern = drop in systolic arterial pressure >10 mm Hg during inspiration (secondary to increase in right heart filling during inspiration at the expense of left heart filling)

• elevated central venous pressure with distended neck veins (jugular distension)

• shortness of breath

• falling blood pressure

• distant heart sounds/friction rub

• ECG: reduced voltage, ST elevation, PR depression, nonspecific T-wave abnormalities

• normal lung fields + normal pulmonary vascularity

• rapid enlargement of heart size

• distension of SVC, IVC, hepatic + renal veins

• periportal edema

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• hepatomegaly

CT:

• right + left ventricles of equal size (due to equalization of ventricular pressures)

Doppler-US:

• episodes of high-velocity hepatopetal flow separated by long intervals of minimal flow

ECHO:

• diastolic collapse of RV

• cyclical collapse of either atrium

Rx:

pericardiocentesis/pericardial drainage

Cardiac Thrombus

• Left Atrial Thrombus

  Associated with:

  mitral valve disease

  • atrial fibrillation

  Site:

  atrial appendage

  • atrial dilatation

  • irregular/lobulated border

  • microcavitations

  • laminated appearance

• Left Ventricular Thrombus

  Site:

  region of ventricular dyskinesia/aneurysm (from prior myocardial infarction)

  • homogeneous attenuation on CT

  • heterogeneous signal on SE MR images

  • low-signal intensity on GRE MR images

DDx:

myxoma (heterogeneous texture on CT)

Cardiomyopathy

• = heart disease as the result of myocardial dysfunction

Dilated and Ischemic Cardiomyopathy

• = Congestive Cardiomyopathy

Etiology:

• Idiopathic

• Myocarditis: viruses, bacteria

• Alcoholism

• Pregnancy/post partum

• Endocardial fibroelastosis = thickened endocardium + reduced contractility

• Infants of diabetic mothers

• Inborn error of metabolism: glycogenosis, mucolipidosis, mucopolysaccharidosis

• Coronary artery disease: myocardial infarction, anomalous origin of left coronary artery, coronary calcinosis

• Muscular dystrophies

• tendency for CHF when EF <40 %

• global 4-chamber enlargement

• poor ventricular contractility (reduced EF)

• LA enlargement without enlargement of LA appendage

• bilateral atrioventricular valve insufficiency

ECHO:

• enlarged LV with global hypokinesis

• IVS and LVPW of equal thickness with decreased amplitude of motion

• low-profile/ miniaturized mitral valve

• mildly enlarged LA (elevated end-diastolic LV pressure)

• enlarged hypokinetic right ventricle

Obstructive Cardiomyopathy (10%)

• = hypertrophic cardiomyopathy

• = disorder of cardiac muscle characterized by nondilated symmetric/eccentric hypertrophy of either/both ventricles in the absence of cardiac/systemic disease

• SYMMETRIC/CONCENTRIC HYPERTROPHY (2 20%)

  • = HYPERTENSIVE HYPERTROPHIC CARDIOMYOPATHY

  • commonly in older women

  • (a) midventricular

  • (b) diffuse

  • (c) apical

  • marked concentric LV hypertrophy

  • small LV cavity

• ASYMMETRIC SEPTAL HYPERTROPHY (ASH)

  • = IDIOPATHIC HYPERTROPHIC SUBAORTIC STENOSIS (IHSS) = SUBAORTIC STENOSIS

  • = HYPERTROPHIC OBSTRUCTIVE CARDIOMYOPATHY

  • basal/upper part of LV septum disproportionately thickened

  • anterolateral wall of LV often also abnormally thick

  • Most common + clinically significant form!

  • systolic obstruction of LV outflow tract

• APICAL HYPERTROPHY (2 33%)

  • = myocardial wall thickening confined to apical portion of LV with sparing of septum

  • usually clinically benign (no obstruction to LV flow)

  • giant inverted T-wave

  • Left ventriculography:

    • spade-shaped deformity of LV cavity

Hemodynamics:

• LV hypertrophy leads to subaortic stenosis, abnormal diastolic function, myocardial ischemia

• rapid blood flow through narrow outflow tract causes the anterior leaflet of mitral valve to displace anteriorly toward septum during systole (Venturi effect)

• mitral regurgitation (from displaced MV leaflet)

Etiology:	autosomal dominant transmission (>50%); sporadic form
Histo:	derangement of myocardial fibers
Age:	3rd 5th decade; occasionally infants + elderly

• dyspnea (75%) from elevated LV diastolic pressure

• angina (66%) from LV outflow obstruction + decreased flow through intramural coronary arteries

• fatigue

• syncope from arrhythmia/decreased cardiac output during exercise because of LV outflow obstruction

• systolic murmur

• normal heart size

• LA enlargement with mitral insufficiency (in 30%)

• prominent left midheart border (septal hypertrophy)

• mild pulmonary venous hypertension

MR:

• marked thickening of LV wall + small LV cavity

• average end-diastolic thickness of septal + posterolateral wall = 23.5 mm + 11.4 mm; ratio 2.1

• increased LV mass (estimated by cine MRI)

• large + prolonged signal void from site of obstruction toward aortic valve within normally high-intensity flowing blood (due to turbulent flow during systole)

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• substantially elevated ejection fraction

• prolonged systolic contact of the anterior mitral valve leaflet with the septum

• systolic flow void from mitral valve into left atrium due to mitral valve regurgitation (on cine MRI)

• impairment of LV relaxation (= abnormal LV stiffness) leads to poor early diastolic filling

ECHO (modality of choice):

• IVS >14 mm thick; posterolateral wall >11 mm thick; IVS:LVPW thickness >1.3:1

• systolic anterior motion of mitral valve (SAM) causing narrowed LVOT in systole

• midsystolic closure of aortic valve

• increased LVOT gradient with late systolic peaking on Doppler

Prognosis:	4% annual mortality rate (sudden death in young patients); progressive LV dilatation, atrial arrhythmia, intractable CHF
Rx:	beta-blockers, calcium antagonists, myomectomy of hypertrophied septum, cardiac transplantation

Restrictive Cardiomyopathy

• = infiltrative process that impairs the myocardial ability to relax normally + impairs ventricular filling

Etiology:

(a) idiopathic: endomyocardial fibroelastosis
(a) infiltrative disease: amyloidosis, hemochromatosis, sarcoidosis, glycogen storage disease, L ffler's hypereosinophilic endocarditis, Gaucher disease
(b) constrictive pericarditis

• varying degrees of pulmonary venous hypertension

• dilatation of RA + IVC reflecting high RV filling pressure (DDx: constrictive pericarditis)

• LA enlargement

Chronic Venous Stasis Disease

• = CHRONIC VENOUS INSUFFICIENCY

• = insufficiency/incompetence of venous valves in deep venous system of lower extremity

Cause:

• postphlebitic valvular incompetence: destruction of valve apparatus results in short thickened valves secondary to scar formation

• primary valvular incompetence: shallow elongated redundant valve cusps prevent effective closure

Associated with:

incompetent venous valves in the calf (secondary to pressure dilatation from stasis in deep venous system) leading to superficial vein varicosities

• edema, induration (= fluid exudation from increased capillary pressure)

• ulceration (from minor trauma + decreased diffusion of oxygen secondary to fibrin deposits around capillaries)

• skin hyperpigmentation (= breakdown products of exudated RBCs)

• aching pain

• venous reflux on descending venography with Valsalva:

  • (a) 82% in deep venous system alone

  • (b) 2% in saphenous vein alone

  • (c) 16% in both

  • bilateral in 75%

Grade:	1 = minimal incompetence	= to level of upper thigh
2 = mild incompetence	= to level of lower thigh
3 = moderate incompetence	= to level of knee
4 = severe incompetence	= to level of calf veins

Coarctation of the Aorta

Coarctation Of Aorta

• = localized obstruction at the junction of aortic arch and descending aorta secondary to a fibrous ridge protruding into aortic lumen

• M:F = 4:1; rare in Blacks

• LOCALIZED COARCTATION

  • = ADULT/postductal/juxtaductal TYPE [former classification]

  • = short discrete narrowing close to ligamentum arteriosum (most common type)

  • Coexistent cardiac anomalies uncommon!

  Location:

  most frequent in juxtaductal portion of arch

  • incidental finding late in life

  • ductus usually closed

  • shelflike lesion at any point along the aortic arch

  • narrow isthmus above the lesion

  • poststenotic aortic dilatation distally

• TUBULAR HYPOPLASIA

  • = INFANTILE/preductal/DIFFUSE TYPE [former classification]

  • = hypoplasia of long segment of aortic arch after origin of innominate artery

  • Coexistent cardiac anomalies common!

  • CHF in neonatal period (in 50%)

  • patent ductus arteriosus

Hemodynamics:

fetus	: no significant change because only 10% of cardiac output flows through aortic isthmus
neonate	: determined by how rapidly the ductus closes; without concurrent VSD overload of LV leads to CHf in 2nd/3rd week of life
Collateral circulation:	via subclavian artery and its branches:

• intercostals

• anterior spinal artery

• lateral thoracic

• internal mammary

• scapular artery

• transverse cervical artery

In 50% associated with:

• Bicuspid aortic valve (in 25-50%), which may result in calcific aortic valve stenosis (after 25 years of age) + bacterial endocarditis

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• Intracardiac malformations: PDA (33%), VSD (15%), aortic stenosis, aortic insufficiency, ASD, tGV, ostium primum defect, truncus arteriosus, double-outlet right ventricle

• Noncardiac malformations (13%): turner syndrome (13-15%)

• Cerebral berry aneurysms

• Mycotic aneurysm distal to CoA

Prognosis:	11% mortality prior to 6 months of age
Rx:	ages 3-5 years are ideal time for operation (late enough to avoid restenosis + early enough before irreversible hypertension occurs); surgical correction past 1 year of age decreases operative mortality drastically; 3-11% perioperative mortality

Procedures:

• Resection + end-to-end anastomosis

• Patch angioplasty

• Subclavian flap (Waldhausen procedure) using left subclavian artery as a flap

Postsurgical Cx:

• Residual coarctation (in 32%)

• Subsequent obstruction (rare)

• Mesenteric arteritis: 2-3 days after surgery secondary to paradoxical hypertension from increased plasma renin

  • abdominal pain, loss of bowel control

• Chronic persistent hypertension symptomatic CoA

Symptomatic CoA

• Second most common cause of CHf in neonate (after hypoplastic left heart)

Time:

(a) toward the end of 1st week of life in critical stenosis
(b) more commonly presents in older child

• lower extremity cyanosis (in tubular hypoplasia)

• left ventricular failure (usually toward end of 1st week of life)

• generalized cardiomegaly

• increased pulmonary vascularity (L-to-R shunt through PDA/VSD)

• pulmonary venous hypertension/edema

• figure 3 sign hidden by thymus

Asymptomatic CoA

• headaches (from hypertension)

• claudication (from hypoperfusion)

• figure 3 sign = indentation of left lateral margin of aortic arch in the region of aortic-pulmonic window (at site of coarctation and poststenotic dilatation)

• reverse 3 sign on barium esophagogram

• elevated left ventricular apex (secondary to left ventricular hypertrophy)

• scalloped contouring of soft-tissues posterior to sternum (= dilated tortuous internal mammary arteries) on LAT CXR (in 28%)

• dilatation of brachiocephalic vessels + aorta proximal to stenosis

• obscuration of superior margin of aortic arch

• inferior rib notching (in 75%; mostly in adults over age 20; unusual before age 6)

Location:	ribs 3 9 (most pronounced in 3rd + 4th ribs, less pronounced in lower ribs); 1st + 2nd rib do not participate because they have arteries originating from subclavian a.
Site:	central + lateral thirds of posterior rib (a) bilateral (b) unilateral on left side: left aortic arch with aberrant right subclavian artery below CoA (c) unilateral on right side: right aortic arch with anomalous left subclavian artery below CoA

Congenital Absence Of Pulmonary Valve

Massive regurgitation between pulmonary artery and RV

In 90% associated with:

VSD, tetralogy of Fallot (50%)

• cyanosis (not in immediate newborn period)

• repeated episodes of respiratory distress

• continuous murmur

• ECG: right ventricular hypertrophy

• prominent main, right, and left pulmonary artery

• RV dilatation (increased stroke volume)

• partial obstruction of right/left mainstem bronchus (compression by vessel)

• right-sided aorta (33%)

Congestive Heart Failure

• = increase in circulating blood volume with diminishing cardiac function leads to elevation of microvascular pressure of lung

Incidence:

most common cause of interstitial + airspace edema of lungs

Cause:

• back pressure from LV: long-standing systemic hypertension, aortic valve disease, coronary artery disease, cardiomyopathy, myocardial infarction

• obstruction proximal to LV: mitral valve disease, LA myxoma, cor triatriatum

Histo:

• Interstitial phase: fluid in loose connective tissue around conducting airways and vessels + engorgement of lymphatics

• Alveolar phase: increase in alveolar wall thickness

• Alveolar airspace phase: alveoli filled with fluid + loss of alveolar volume; pulmonary fibrosis upon organization of intraalveolar fibrin (if chronic)

• large heart

• Interstitial pulmonary edema (invariably precedes alveolar edema)

  • NO abnormal physical finding

  • hypoxemia (ventilation-perfusion inequality)

  • loss of sharp definition of vascular markings

  • thickening of interlobular septa (pulmonary venous wedge pressure 17 20 mm Hg)

  • poorly defined increased bronchial wall thickness

  • thickening of interlobar fissures (due to fluid in subpleural connective tissue layer)

• Airspace edema

  Cause:

  acute LA pressure elevation with volume of capillary filtration exceeding that of lymphatic drainage

  • severe dyspnea/orthopnea

  • tachypnea + cyanosis

  P.632

  
  

  • dry cough/copious frothy sputum

  • hypoxemia (vascular shunting)

  • poorly defined patchy acinar opacities

  • coalescence of acinar consolidation, particularly in medial third of lung

  • butterfly/bat-wing distribution of consolidation

  • (= consolidated hilum + uninvolved lung cortex)

• Flow inversion

  Cause:

  chronic elevation of LA pressure (as in left heart failure/mitral valve disease)

  Pathophysiology:

  • long-standing elevation of LA pressure causes an increase in atriovenous reflux; initially the increased LA pressure is met with an increased tonus of the LA wall (= absence of atrial enlargement in acute left heart failure); eventually LA enlarges inciting a protective atrial-pulmonary-vascular reflex vasospasm, which narrows the lower lobe vessels and decreases atriovenous reflux

  • basal oligemia

  • hyperemia of upper lobes

  N.B.:

  flow inversion is never seen in pulmonary edema of renal failure/overhydration/low oncotic pressure

• Generalized oligemia

  Cause:

  aortic valvular disease

Extrathoracic Manifestations of CHF

• @ Hepatobiliary

  • GB wall edema

  • periportal edema

  • enlarged IVC

Constrictive Pericarditis

• = PERICARDIAL CONSTRICTION

• = fibrous thickening of pericardium interfering with filling of ventricular chambers through restriction of heart motion

Age:

30 50 years; M:F = 3:1

• elevation + equilibration of end-diastolic ventricular pressures

Etiology:

• IDIOPATHIC (2nd most common today)

• INFECTIOUS/INFLAMMATORY

  • Viral (Coxsackie B)

  • Tuberculosis (formerly most common etiology)

  • Rheumatoid arthritis

• TRAUMATIC

  • Cardiac surgery (most common)

  • Radiotherapy to mediastinum

• UREMIA = chronic renal failure

• NEOPLASTIC = tumor invasion

Causes of acute pericarditis:

mnemonic:

MUSIC

• Myocardial infarction (acute)

• Uremia

• Surgery (cardiac)

• Infection

• Cancer

• dyspnea + weakness

• abdominal enlargement (ascites + hepatomegaly)

• peripheral edema

• pericardial knock sound = loud early-diastolic sound

• neck vein distension

• Kussmaul sign = failure of venous pressure to fall (= elevation of jugular venous pressure) with inspiration

• prominent X and Y descent on venous pressure curve

• linear/plaquelike pericardial calcifications (50 70%): predominantly over RV, posterior surface of LV, in atrioventricular groove

• dilatation of SVC (77%), azygos vein (69%)

• small atria; occasionally compensatory dilatation of nonconstricted portions, eg, LA enlargement (20%)

• normal/small-sized heart (enlargement only due to preexisting disease)

• normal pulmonary vascularity/pulmonary venous hypertension (43%)

• straightening of heart borders:

  • straight/concave on right side

  • squared on left side

  • pericardial tenting

• increase in ejection fraction (small EDV)

• pleural effusion (34% bilateral, 26% right PE)

CT:

• epicardium = visceral pericardium >2 mm thick

• dilatation of SVC + IVC

• reflux of contrast into coronary sinus

• flattening of right ventricle + curvature of interventricular septum toward left

• pleural effusion + ascites

MR:

• pericardium thickened to 4 mm

• pericardium of intermediate signal intensity similar to myocardium sandwiched between high-signal epicardial and mediastinal fat (on T1WI); most easily identified anterior to RV > RA > free wall of LV

• often small LV + tubular appearing RV

• dilatation of RA + IVC reflecting high RV filling pressure (DDx: restrictive cardiomyopathy)

• flattened/sigmoid-shaped septum

ECHO (nonspecific features):

• thickening of pericardium (not reliably demonstrated unless pericardial fluid present)

• immobile pericardium

• rapid early filling of LV

• rapid early filling motion followed by flat posterior wall motion during diastasis period (= period between early rapid filling and atrial contraction)

• premature opening of pulmonic valve

Cx:	protein-losing enteropathy (increased pressure in IVC + portal vein)
Rx:	surgical stripping of pericardium
DDx:	(a) restrictive physiology: 1. Cardiac tamponade 2. Restrictive cardiomyopathy (eg, amyloid) (b) nonrestrictive physiology: 1. S/P recent cardiac surgery 2. Organized intrapericardial hematoma

Coronary Artery Fistula

• = single/multiple fistulous connections between a coronary artery (R > L) and other heart structures

Abnormal communication with (>90 % right heart):

• RV > RA > pulmonary trunk > coronary sinus > SVC

P.633

Hemodynamics:

L-to-R shunt; pulmonary:systemic blood flow = <1.5:1 (usually)

• may have normal CXR (in small shunts)

• cardiomegaly + shunt vascularity (in large shunts)

Angio:

• dilated tortuous coronary a. with anomalous connection

Cor Triatriatum

• = rare congenital anomaly in which a fibromuscular septum with a single stenotic/fenestrated/large opening separates the embryologic common pulmonary vein from the left atrium:

  • proximal/accessory chamber lies posteriorly receiving pulmonary veins

  • distal/true atrial chamber lies anteriorly connected to left atrial appendage + emptying into LV through mitral valve

Etiology:	failure of common pulmonary vein to incorporate normally into left atrium
Associated with:	ASD, PDA, anomalous pulmonary venous drainage, left SVC, VSD, tetralogy of Fallot, atrioventricular canal

• dyspnea, heart failure, failure to thrive

• clinically similar to mitral valve stenosis

• pulmonary venous distention + interstitial edema + dilatation of pulmonary trunk and pulmonary arteries (in severe obstruction)

• enlarged RA + RV

• mild enlargement of LA

Angio:

• dividing membrane on levophase of pulmonary arteriogram

Prognosis (if untreated):

• usually fatal within first 2 years of life; 50% 2-year survival; 20% 20-year survival

Rx:

surgical excision of obstructing membrane

Deep Vein Thrombosis

• =DVT

Incidence:

140,000 250,000 new cases per year in United States with an estimated sole/major cause of 50,000 200,000 deaths per year (15% of in-hospital deaths); 6 7 million stasis skin changes; in 0.5% cause of skin ulcers

Pathogenetic factors:

• Hypercoagulability

• Decreased blood flow/stasis

• Intimal injury

• Decreased fibrinolytic potential of veins

• Platelet aggregation

Risk factors:

• Surgery, esp. on legs/pelvis: orthopedic (45 50%) especially total hip replacement >50%), gynecologic (7 35%), neurosurgery (18 20%), urologic (15 35%), general surgery (20 25%)

• Severe trauma

• Prolonged immobilization: hemiplegic extremity, paraplegia + quadriplegia, casting/orthopedic appliances

• Malignancy (risk factor 2.5) = Trousseau syndrome

• Obesity (risk factor 1.5)

• Diabetes

• Pregnancy (risk factor 5.5) and for 8 12 weeks postpartum

• Medication: birth control pills, estrogen replacement, tamoxifen (risk factor 3.2)

• Decreased cardiac function: congestive heart failure, myocardial infarction (20 50%; risk factor 3.5)

• Age >40 years (risk factor 2.2)

• Varicose veins

• Previous DVT (risk factor 2.5)

• Patients with blood group A > blood group 0

• Polycythemia

• Smoking

Pathologic terminology:

• organized thrombus = transition to a vascularized lesion of connective tissue adherent to vessel wall

• recanalized thrombus = vascular channel network within an organized clot reducing it to septations of collagen and elastic fibers often lined by endothelium

Location:

• Dorsal veins of calf ( ascending thrombosis)

• Iliofemoral veins ( descending thrombosis)

• Peripheral + iliofemoral veins simultaneously

• rare: internal iliac v., ovarian v., ascending lumbar vv.

Side:

L:R = 7:3 due to compression of left common iliac v. by left common iliac a. (arterial pulsations lead to chronic endothelial injury with formation of intraluminal spur, which is present in 22% of autopsies + in 90% of patients with DVT)

• Local symptoms due to obstruction/phlebitis usually only when (a) thrombus occlusive, (b) clot extends into popliteal/more proximal vein (14 78% sensitivity, 4 21% specificity):

  • warmth

  • swelling (measurement of circumference)

  • blanching of skin (phlegmasia dolens alba)/blue leg with complete obstruction (phlegmasia cerulea dolens)

  • deep crampy pain in affected extremity, worse in erect position, improved while walking

  • tenderness along course of affected vein

  • Homans sign = calf pain with dorsal flexion of foot

  • Payr sign = pain upon compression of sole of foot

  • 2/3 of deep vein thromboses are clinically silent:

    • DVT diagnosed ante mortem in <30%

    • Only 10 33% of patients with fatal PE are symptomatic for DVT

  • Clinically suspected DVT accurate in only 26 45%:

    • DVt symptomatology due to other causes in 15-35% of patients

  • Negative bilateral venograms in 30% of patients with angiographically detected pulmonary emboli (big bang theory = clot embolizes in toto to the lung leaving no residual in vein)

Venography (89% sensitivity, 97% specificity):

• false negative in 11%, false positive in 5%; study aborted/nondiagnostic in 5%

Risk:

postvenography phlebitis (1 2%), contrast reaction, contrast material-induced skin slough, nephropathy

• intraluminal filling defect constant on all images

• nonfilling of calf veins

• inadequate filling of common femoral vein + external + common iliac veins

P.634

B-Mode US (88-100% sensitivity, 92-100% specificity, >90% accuracy for DVt in thigh and popliteal veins):

• lack of complete luminal collapse with venous compression (DDx: deformity + scarring from prior DVt; technical difficulties in adductor canal + distal deep femoral vein)

• visualization of clot within vein (DDx: slow flowing blood; machine noise)

• <75% increase in diameter of common femoral vein during Valsalva

• venous diameter at least twice that of adjacent artery suggests thrombus <10 days old

Doppler US:

• absence of spontaneity (= any waveform recording), not reliable in peripheral veins

• continuous venous signal = absence of phasicity (= no cyclic variation in flow velocity with respiration, ie, decrease in expiration + increase in inspiration) is suspicious for proximal obstruction

• attenuation/absence of augmentation (= no increase in flow velocity with distal compression) indicates venous occlusion/compression in intervening venous segments

• pulsatile venous flow is a sign of congestive heart failure/pericardial effusion/cardiac tamponade/pulmonary embolism with pulmonary hypertension

Venous Occlusion Plethysmography:

• = temporary obstruction of venous outflow by pneumatic cuff around mid-thigh inflated above venous pressure leads to progressive increase in blood volume in lower leg; upon release of cuff limb quickly returns to resting volume with prompt venous runoff; limb blood volume changes are measured by impedance plethysmography in which a weak alternating current is passed through the leg; the electrical resistance varies inversely with blood volume; the current strength is held constant and voltage changes directly reflect blood volume changes

• 87-95-100% sensitivity, 92-100% specificity for aboveknee DVt

• 17-33% sensitivity for below-knee DVt

• initial rise in venous volume (= venous capacitance) diminished

• delay in venous outflow = fall measured at 3 seconds

False positives (6%):	severe cardiopulmonary disease, pelvic mass, reduced arterial inflow
False negatives:	calf vein thrombosis, small thrombus

I-125-Labeled fibrinogen:

• 90% sensitive for calf vein thrombus

• 60 80% sensitive for femoral vein thrombus

• insensitive for thrombus in upper thigh/pelvis

Risk:	results not available for several days, transmission of viral infection
False positives:	hematoma, inflammation, wound, old small thrombus isolated in common femoral/iliac vein

Cx:

• Pulmonary embolism (50%): in 90% from lower extremity/pelvis; in 60% with proximal free-floating / widow-maker thrombus; occurs usually between 2nd to 4th (7th) day of thrombosis

  • Source of pulmonary emboli:

    • multiple sites (1/3), cryptogenic in 50%;

    (a) lower extremity	(46%)
    (b) inferior vena cava	(19%)
    (c) pelvic veins	(16%)
    (d) mural heart thrombus	(4.5%)
    (e) upper extremity	(2%)

  • Likelihood of pulmonary embolism:

    • 77% for iliac veins, 35 67% for femoropopliteal vein, 0 46% for calf veins

• Postphlebitic syndrome (PPS) in 20% of cases with DVT (= recanalization to a smaller lumen, focal wall changes) due to valvular incompetence

• Phlegmasia cerulea/alba dolens (= severely impaired venous drainage resulting in gangrene)

Prognosis:	tibial/peroneal venous thrombi resolve spontaneously in 40%, stabilize in 40%, propagate into popliteal vein in 20%
Prophylaxis:	intermittent compression of legs, heparin, warfarin

Rx:

• Heparin IV

• Systemic anticoagulation (warfarin) for 3 months decreases risk of recurrent DVT in initial 3 months from 50% to 3% + fatal pulmonary embolism from 30% to 8%; necessity for anticoagulation in DVT of calf veins is controversial

• Caval filter (10 15%) in patients with contraindication/complication from anticoagulation or progression of DVT/PE despite adequate anticoagulation

DDx:

pseudothrombophlebitis (= signs + symptoms of DVT produced by popliteal cyst/traumatic hematoma)

Double-Outlet Right Ventricle

• = DORV = TAUSSIG-BING HEART

• = most of the aorta + pulmonary artery arise from the RV secondary to maldevelopment of conotruncus

Type 1	= aorta posterior to pulmonary artery + spiraling course (most frequent)
Type 2	= Taussig-Bing heart = aorta posterior to pulmonary artery + parallel course
Type 3	= aorta anterior to pulmonary artery + parallel course

Hemodynamics:

fetus	: no CHF in utero (in absence of obstructing other anomalies)
neonate	: ventricular work overload leads to CHF
Associated with:	VSD (100%), pulmonary stenosis (50%), PDA

• aorta overriding the interventricular septum with predominant connection to RV

• aorta posterior/parallel/anterior to pulmonary artery

• LV enlargement (volume overload)

Ductus Arteriosus Aneurysm

• = fusiform aneurysm of ductus arteriosus, usually patent toward aorta + completely/incompletely occluded toward pulmonary artery

Incidence:

<100 cases

Classification:

• according to age: infantile, childhood, adult type

• according to cause: congenital, infectious, traumatic

P.635

Pathogenesis:	? delay in closure,? myxoid degeneration of ductus wall,? abnormal elastic fibers
Age:	most <2 months of age

• dyspnea, tachypnea, hoarseness

• pulmonary artery displaced anteromedially

• distal aortic arch displaced laterally

CXR:

• left-sided upper mediastinal mass in aorticopulmonary window

• tracheal displacement to right + anteriorly/posteriorly

• consolidation of adjacent lung (compression, fibrosis, hemorrhage)

CT:

• contrast-enhancing mass in classic location

ECHO:

• cystic mass with pulsatile flow

Cx:	rupture, dissection, infection, thromboembolic disease, phrenic nerve compression
Prognosis:	usually fatal (without prompt surgery)

Ebstein Anomaly

• = downward displacement of septal + posterior leaflets of dysplastic tricuspid valve with ventricular division into

  • a large superior atrialized inflow portion with thin ventricular wall (incorporating part of the RV into the RA), and

  • a small inferior functional chamber with shortened chordae tendineae

Valve morphology:

• inappropriately low attachment of posterior septal malformed defective valve leaflets; only anterior leaflet attaches normal to tricuspid annulus, but it can be dysplastic/sail-like

Etiology:

chronic maternal lithium intake (10%)

Hemodynamics:

• tricuspid valve insufficiency leads to tricuspid regurgitation ( ping-pong volume) + severely dilated RA; RA dilatation stretches interatrial septum causing incompetence of foramen ovale (R-to-L shunt) in 75%

• cyanosis in neonatal period (depending on degree of R-to-L shunt): may improve/disappear postnatally with decrease in pulmonary arterial pressure

• CHF in utero/in neonate (in 50%)

• systolic murmur (tricuspid insufficiency)

• Wolff-Parkinson-White syndrome (10%) = paroxysmal supraventricular tachycardia/right bundle branch block (responsible for sudden death)

Cause:

conduction system develops during formation of tricuspid valve adjacent to it

• boxlike/funnel-like cardiomegaly (enlargement of RA + RV)

• extreme RA enlargement (secondary to insufficient tricuspid valve)

• IVC + azygos dilatation (secondary to tricuspid regurgitation)

• hypoplastic aorta + pulmonary trunk (the ONLY cyanotic CHD to have this feature)

• normal LA

• calcification of tricuspid valve may occur

MR:

• marked right atrial enlargement

• small right ventricle dilatation of RV infundibulum

ECHO:

• large sail-like tricuspid valve structure within dilated right heart

• tricuspid regurgitation identified by Doppler ultrasound

Prognosis:	50% infant mortality; 13% operative mortality
Survival rate:	70% at 2 years, 50% at 13 years; survival into adulthood if valve functions normally
Rx:	1. Digitalis + diuretics 2. Tricuspid valve prosthesis

Eisenmenger Complex

• = EISENMENGER DEFECT

• (1) high VSD overriding aorta with hypoplastic crista supraventricularis

• (2) RV hypertrophy

  • and as consequence of increased pulmonary blood flow:

• (3) dilatation of pulmonary artery + branches

• (4) intimal thickening + sclerosis of small pulmonary arteries + arterioles

• cyanosis appears in 2nd + 3rd decade with shunt reversal

Eisenmenger Syndrome

• = EISENMENGER REACTION

• = development of high pulmonary vascular resistance after many years of increased pulmonary blood flow secondary to L-to-R shunt (ASD, PDA, VSD), which leads to a bidirectional (= balanced) shunt and ultimately to R-to-L shunt

Etiology:

• pulmonary microscopic vessels undergo reactive muscular hypertrophy, endothelial thickening, in situ thrombosis, tortuosity + obliteration; once initiated, pulmonary hypertension accelerates the vascular reaction, thus increasing pulmonary hypertension in a vicious cycle with RV failure + death

Path:

adaptive anastomotic pathways connect plexiform lesions of pulmonary arterial vessels to bronchial arteries supplying terminal bronchioles + vasa vasorum of pulmonary arteries

Pathologic classification of severity (Heath & Edwards):

Grade I	= medial hypertrophy of muscular pulmonary arteries and arterioles potentially reversible
Grade II	= grade I + intimal proliferation in small muscular arteries and arterioles potentially reversible
Grade III	= grade II + intimal laminar fibrosis + progressive vessel obliteration borderline for reversibility
Grade IV	= occlusion of vessels with progressive aneurysmal dilatation of small arteries nearby irreversible
Grade V	= tortuous glomeruloid channels within proliferation of endothelial cells (= plexiform + angiomatoid lesions) irreversible
Grade VI	= thrombosis + necrotizing arteritis irreversible

P.636

CXR:

• pronounced dilatation of central pulmonary arteries (pulmonary trunk, main pulmonary artery, intermediate branches)

• pruning of peripheral pulmonary arteries

• enlargement of RV + RA (proportionate to volume overload)

• LA + LV return to normal size (with decrease of L-to-R shunt due to markedly elevated pulmonary vascular resistance)

• normal pulmonary veins (unless superimposed cardiac volume overload):

  • pulmonary veins NOT distended (NO increase in pulmonary blood flow)

  • NO redistribution of pulmonary veins (normal venous pressure)

CT:

• linear calcification + thrombus in central pulmonary arteries

• mural calcification/aneurysmal dilatation of ductus arteriosus (in cases of patent ductus arteriosus)

Dx:

measurement of pulmonary artery pressure + flow via catheter

Endocardial Cushion Defect

• =ECD = ATRIOVENTRICULAR SEPTAL DEFECT

  • = PERSISTENT OSTIUM atrioventriculare COMMUNE = PERSISTENT COMMON ATRIOVENTRICULAR CANAL

• = persistence of primitive atrioventricular canal + anomalies of AV valves

• INCOMPLETE/PARTIAL ECD

  • = (1) Ostium primum ASD

  • (2) Cleft in anterior mitral valve leaflet/trileaflet

  • (3) Accessory short chordae tendineae arising from anterior MV leaflet insert directly into crest of deficient ventricular septum

  • left atrioventricular valve usually has 3 leaflets with a wide cleft between anterior + septal leaflet

  • gooseneck deformity secondary to downward attachment of anterior MV leaflet close to inter-ventricular septum by accessory chordae tendineae

  • communication between LA RA or LV RA, occasionally LV RV

  • right atrioventricular valve usually normal

• TRANSITIONAL/INTERMEDIATE ATRIOVENTRICULAR CANAL (uncommon)

  • = (1) Ostium primum ASD

  • (2) High membranous VSD

  • (3) Wide clefts in septal leaflets of both AV valves

  • (4) Bridging tissue between anterior + posterior common leaflet of both AV valves

• COMPLETE ECD = AV COMMUNIS = COMMON AV CANAL

  • = (1) Ostium primum ASD above

  • (2) Posterior inlet VSD below

  • (3) One AV valve common to RV + LV with 5 6 leaflets

    • anterior common bridging leaflet

    • two lateral leaflets

    • posterior common bridging leaflet

Type 1	= chordae tendineae of anterior bridging leaflet attached to both sides of ventricular septum
Type 2	= chordae tendineae of anterior leaflet attached medially to anomalous papillary muscle within RV, but unattached to septum
Type 3	= free-floating anterior leaflet with chordae attachments to septum; only type becoming symptomatic in infancy!

Associated with:

• Down syndrome:

  • in 25% of trisomy 21 an ECD is present;

  • in 45% of ECD trisomy 21 is present

• Asplenia, polysplenia

  • common atrioventricular orifice

  • oval septal defect consisting of a low ASD + high VSD

  • atrial septum secundum usually spared ( common atrium if absent)

  • frequently associated with mesocardia/dextrocardia

Hemodynamics:

fetus:	atrioventricular valves frequently incompetent leading to regurgitation + CHF
neonate:	L-to-R shunt after decrease of pulmonary vascular resistance resulting in pulmonary hypertension

• incomplete right bundle branch block (distortion of conduction tissue)

• left-anterior hemiblock

CXR:

• Radiographic findings similar to ASD, but more marked

• increased pulmonary vascularity (= shunt vascularity)

• redistribution of pulmonary blood flow (mitral regurgitation)

• enlarged pulmonary artery

• diminutive aorta (secondary to L-to-R shunt)

• cardiac enlargement out of proportion to pulmonary vascularity (L-to-R shunt + mitral insufficiency)

• enlarged RV + LV

• enlarged RA (LV blood shunted to RA)

• normal-sized LA (secondary to ASD)

ECHO:

• visualization of ASD + VSD + valve + site of insertion of chordae tendineae

• paradoxical anterior septal motion (secondary to ASD)

• atrioventricular insufficiency + shunts identified by Doppler ultrasound

Angio:

• AP projection:

  • gooseneck deformity of LVOT (in diastole)

  • cleft in anterior leaflet of mitral valve (in systole)

  • mitral regurgitation

• Hepatoclavicular projection in 45 LAO + C-C 45 (= 4-chamber view):

  • best view to demonstrate LV-RA shunt

  • best view to demonstrate VSD (inflow tract + posterior portion of interventricular septum in profile)

• LAT projection:

  • irregular appearance of superior segment of anterior mitral valve leaflet over LVOT

Prognosis:

54% survival rate at 6 months, 35% at 12 months, 15% at 24 months, 4% at 5 years; 91% long-term survival with primary intracardiac repair, 4 17% operative mortality

P.637

Endocardial Fibroelastosis

• = diffuse endocardial thickening of LV + LA from deposition of collagen + elastic tissue

Etiology:

• ? viral infection

• Secondary endocardial fibroelastosis

  • = subendocardial ischemia in critical LVOT obstruction: aortic stenosis, coarctation, hypoplastic left heart syndrome

• sudden onset of CHF during first 6 months of life

• mitral insufficiency:

  • involvement of valve leaflets

  • shortening + thickening of chordae tendineae

  • distortion + fixation of papillary muscles

• enlarged LV = dilatation of hypertrophied LV from mitral regurgitation

• restricted LV motion

• enlarged LA

• pulmonary venous congestion + pulmonary edema

• LLL atelectasis (= compression of left lower lobe bronchus by enlarged LA)

Prognosis:

mortality almost 100% by 2 years of age

Fibromuscular Dysplasia

• = nonatherosclerotic angiopathy of unknown pathogenesis caused by proliferation of muscular + fibrous elements in middle- and large-caliber arteries

Incidence:	<1% of cerebral angiographies; 1,100 patients reported (by 1982)
Age:	children + young adults <30 40 years; 2/3 >50 years; M:F = 1:3 to 1:4

• hypertension

• progressive renal insufficiency

• decreased peripheral pulses, bruit

• asymmetric limb pressures

• neurologic deficits

Location:

• @ Cephalic arteries:

  • cervical + intracranial ICA (85%), extracranial carotid artery (30%), vertebral artery (7%); both anterior + posterior circulation (8%); bilateral (60 65%)

  Associated with:

  brain ischemia (up to 50%), intracranial aneurysms (up to 30%), intracranial tumors (30%), bruits, trauma

• @ Abdominal aorta:

  • renal artery (60%), other aortic branches (in 1 2%: celiac a., hepatic a., splenic a., mesenteric a., iliac a.)

  • Simultaneous involvement of renal/muscular arteries in 3%

• 1. INTIMAL FIBROPLASIA (1 2%)

  • = intimal hyperplasia

  • progressive

  Path:	circumferential/eccentric fibrous tissue between intima + internal elastic lamina
  Age:	children + young adults; M:F = 1:1
  Site:	main renal artery + major segmental branches; often bilateral

  • focal narrow annular radiolucent band

  • smooth tubular stenosis

  • poststenotic fusiform dilatation

  Cx:	spontaneous dissection
  DDx:	atherosclerosis, Takayasu arteritis

• 2. MEDIAL FIBROPLASIA (60 85%)

  • = fibromuscular hyperplasia = medial fibroplasia with microaneurysm

  Age:	20 50 years; typically affects women; common cause of renal artery stenosis in children
  Path:	multiple fibromuscular ridges + severe mural thinning with loss of smooth muscle + internal elastic lamina
  Site:	mid + distal renal artery + branches; bilateral in 50%

  • string-of-beads sign = alternating areas of weblike stenoses + aneurysms (which exceed the normal diameter of the artery)

  • single tubular focal stenosis

  Cx:

  dissection

• 3. perimedial FIBROPLASIA (rare)

  • = subadventitial fibroplasia

  Age:	young females
  Path:	fibroplasia of outer 1/2 of media replacing external elastic lamina
  Site:	distal (mostly right) main renal artery

  • long irregular stenosis

  • beading = NO aneurysm formation (diameter of beads not wider than normal diameter of artery)

• 4. MEDIAL HYPERPLASIA (5 15%)

  • = FIBROMUSCULAR HYPERPLASIA

  Path:	smooth muscle + fibrous tissue hyperplasia within arterial media
  Site:	main renal artery and branches

  • long smooth concentric tubular narrowing

  DDx:

  Takayasu arteritis, sclerosing arteritis, vessel spasm, arterial hypoplasia

• 5. ADVENTITIAL FIBROPLASIA (<1%)

  • = subadventitial/Periadventitial hyperplasia

  Path:	adventitial + periarterial proliferation in fibrofatty tissue
  Site:	main renal artery, large branches

  • long segmental stenosis

  • added to original 5 types:

• 6. MEDIAL DISSECTION (5 10%)

  Path:	new channel in outer 1/3 of media within external elastic lamina
  Site:	main renal artery + branches

  • false channel, aneurysm

• 7. ATYPICAL FIBROMUSCULAR DYSPLASIA

  • (=? variant of intimal fibroplasia)

  • web = smooth/corrugated mass involving only one wall of vessel + projecting into lumen

  DDx:

  atherosclerotic disease, posttraumatic aneurysm

  VARIANT:

  segmental mediolytic arteriopathy

  • = rare noninflammatory disease of small + medium arteries

  Histo:

  focal segmental disruption of medial smooth muscle cells with mediolysis

  • string-of-beads appearance

  • irregular stenoses + aneurysms

Cx:

dissection (in 3%), macroaneurysm formation, intramural hemorrhage

P.638

Prognosis:	tends to remain stable/minimal progression of lesions in 20% causing decline in renal function
Rx:	(1) Resection of diseased segment with end-to-end anastomosis (2) Replacement by autogenous vein graft, excision + repair by patch angioplasty (3) transluminal balloon angioplasty (90% success rate with very low restenosis rate)

Flail Mitral Valve

Cause:

• ruptured chordae tendineae in rheumatic heart disease, ischemic heart disease, bacterial endocarditis

• rupture of head of papillary muscle in acute myocardial infarction, chest trauma

Location:

chordae to leaflet from posteromedial papillary muscle (single vessel blood supply)

• deep holosystolic posterior movement

• random anarchic motion pattern of flail parts in diastole

• excessively large amplitude of opening of aML

HeterOtaxy Syndrome

[hetero, Greek = different; taxis, Greek = arrangement]

• = CARDIOSPLENIC SYNDROMES

• = situs ambiguus with a spectrum of various congenital truncal abnormalities + frequently cardiac malformations from asplenia to polysplenia

Embryology:

• primary defect in lateralization with disruption of complete separation of cardiac chambers during 20 30 days of gestation

Inheritance:

multifactorial (autosomal dominant, autosomal recessive, X-linked recessive)

Individualized approach of classification:

• describes all critical structures by analyzing

• position of atria

• position of venous drainage below diaphragm relative to midline

• position of aorta relative to midline

• position of the stomach + presence of malrotation

• position of liver + gallbladder

• position of cardiac apex

• presence, appearance, and number of spleens

• presence of bi-/trilobed lungs

Asplenia syndrome

• = BILATERAL RIGHT-SIDEDNESS = RIGHT ISOMERISM = IVEMARK SYNDROME

Incidence:

1:1,750 1:40,000 livebirths; M >

Associated with:

• CHD (in 50%):

  • TAPVR (almost 100%), endocardial cushion defect (85%), single ventricle (51%), TGA (58%), pulmonary stenosis/atresia (70%), dextrocardia (42%), mesocardia, VSD, ASD, absent coronary sinus, common atrium, common hepatic vein

• GI anomalies:

  • Partial/total situs inversus, annular pancreas, agenesis of gallbladder, ectopic liver, esophageal varices, duplication + hypoplasia of stomach, Hirschsprung disease, hindgut duplication, imperforate anus

• GU anomalies (15%):

  • Horseshoe kidney, double collecting system, hydroureter, cystic kidney, fused/horseshoe adrenal, absent left adrenal, bilobed urinary bladder, bicornuate uterus

• Cleft lip/palate, scoliosis, single umbilical artery, lumbar myelomeningocele

• cyanosis in neonatal period/infancy (if severe cyanotic CHD)

• severe respiratory distress

• Howell-Jolly bodies = RBC inclusions in patients with absent spleen

• cardiac apex discordant from stomach + liver

• absent spleen (risk of sepsis)

• @ Lung

  • bilateral trilobed lungs = bilateral minor fissures (SPECIFIC)

  • bilateral eparterial bronchi (MR/tomogram) = pulmonary arteries inferior to bronchi on PA view + projecting anterior to trachea on LAT view

  • diminished pulmonary vascularity/pulmonary venous hypertension (TAPVR below diaphragm)

• @ Heart & great vessels

  • bilateral systemic/right atria with broad-based appendages

  • ipsilaterality of abdominal aorta + IVC

    • = juxtaposed piggybacked IVC (aorta usually posterior) (MOST RELIABLE INDICATOR)

  • bilateral SVC

• @ Abdomen

  • absent spleen

  • centrally located bridging liver = hepatic symmetry

  • stomach on right/left side/in central position and small (microgastria)

Prognosis:

up to 80% mortality by end of 1st year of life

Polysplenia Syndrome

• = BILATERAL LEFT-SIDEDNESS = LEFT ISOMERISM

Age:

presentation in infancy/adulthood; M < F

Associated with:

• CHD (>50%):

  • APVR (70%), dextrocardia (37%), ASD (37%), ECCD (43 65%), pulmonic valvular stenosis (23%), TGA (13 17%), DORV (13 20%)

  • no/mild CHD in most patients

• GI abnormalities:

  • esophageal atresia, TE fistula, gastric duplication, preduodenal portal vein, duodenal webs + atresia, short bowel, mobile cecum, malrotation, semiannular pancreas, biliary atresia, absent gallbladder

• GU anomalies (15%):

  • renal agenesis, renal cysts, ovarian cysts

• Vertebral anomalies, common celiac trunk SMA

• CHF (due to L-to-R shunt)

• heart murmur, occasional cyanosis

• leftward/superiorly directed P-wave vector

• heart block (due to ECCD)

• extrahepatic biliary obstruction

• absence of IVC (on LAT CXR)

• large azygos vein (on AP CXR) may mimic aortic arch

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• @ Lung

  • bilateral morphologic left lungs (55-C68%), normal (18%), bilateral R-sided lungs (7%)

  • bilateral hyparterial bronchi (= arteries projecting superior to bronchi on PA view + posterior to tracheobronchial tree on LAt view)

  • normal/increased pulmonary vascularity

  • absence of middle lobe fissure

• @ Heart & great vessels

  • bilateral pulmonary/left atria + pointed, tubular, narrow-based appendages

  • cardiac apex on R/in midline

  • bilateral SVC (50%)

  • interruption of hepatic segment of IVC with azygos/hemiazygos continuation in 65 70% (MOST CONSISTENT FINDING)

• @ Abdominal heterotaxy (56%)

  • presence of 2 spleens (usually two major + indefinite number of splenules) located on both sides of the mesogastrium (esp. greater curvature of stomach)

  • centrally located liver = hepatic symmetry

  • absence of gallbladder (50%)

  • stomach always on same side of spleen(s)

  • malrotation of bowel (80%)

  • preduodenal portal vein

OB-US:

• absence of intrahepatic IVC

• aorta anterior to spine in midline

• double vessel sign = 2 vessels of similar size in paraspinous location posterior to heart = aorta + azygos vein on left/right side of spine

Prognosis:

50% mortality by 4 months;
75% mortality by 5 years;
90% mortality by midadolescence

Heterotaxy syndromes
	Asplenia = bilateral right sidedness	Polysplenia = bilateral left sidedness
Clinical
Presenting age	newborn/infant	infant/adult
Sex predominance	male	female
Cyanosis	severe	usually absent
Heart disease	severe	moderate/none (5 10%)
Howell-jolly/Heinz bodies	present	absent
Spleen scan	no spleen	multiple small spleens
Characteristic eCG	none	abnormal P-wave vector
Prognosis	poor	good
Mortality	high	low
Plain radiograph
Lung vascularity	decreased	normal/increased
Aortic arch	right/left	right/left
Cardiac apex	right/left/midline	right/left
Bronchi	bilateral eparterial	bilateral hyparterial
Minor fissure	possibly bilateral	none/normal
Stomach	midline/right/left	right/left
Liver	symmetrical/R/L	in various positions
Malrotation of bowel	yes (microgastria)	yes
Cardiography
Coronary sinus	usually absent	sometimes absent
Atrial septum	common atrium (100%)	ASD (84%)
AV valve	atresia/common valve	normal/abnormal MV
Single ventricle	44%	infrequent
IVS	VSD	VSD common
Great vessels	d-/l-transposition (72%)	normal relationship
Pulmonary stenosis	the rule	frequent
Pulmonary veins	tAPVR	PAPVR (42%) tAPVR (6%)
Single coronary artery	19%
SVC	bilateral (53%)	bilateral (33%)
IVC-aorta relationship	same side of spine	normal
IVC	normal	interrupted (84%)/normal
Azygos vein	inapparent	continuation R/L

Hypoplastic Left Heart Syndrome

• = SHONE SYNDROME = AORTIC ATRESIA

• = underdevelopment of left side of heart characterized by

  • hypoplastic/atretic aortic valve

  • hypoplastic/atretic mitral valve

  • hypoplastic LV (due to endocardial fibroelastosis)

  • hypoplastic ascending aorta

  • normally related great vessels

  Prevalence:

  0.2/1,000 live births; M:F = 2:1

  • 4th most common cardiac malformation manifesting in 1st year of life (after VSD, TGV, tetralogy of Fallot)

  • Most common cause of CHF in neonate

  • Responsible for 25% of all cardiac deaths in 1st week of life

Hemodynamics:

pulmonary venous blood in LA faces an atretic/stenotic MV (= pulmonary venous outflow obstruction) and is diverted to RA through herniated foramen ovale/ASD (L-to-R shunt); RV supplies (a) pulmonary artery, (b) ductus arteriosus, (c) descending aorta (antegrade flow), (d) aortic arch + ascending aorta + coronary circulation (retrograde flow) leading to RV work overload + CHF

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• Associated malformations:

  • coarctation of aorta, PDA, patent foramen ovale, dilated pulmonary artery, VSD, dilated RA, enlarged RV, double-outlet right ventricle, endocardial fibroelastosis

• severe CHF (RV volume + pressure overload):

  • characteristically presents within first few hours of life

• ashen gray color/dusky complexion (systemic underperfusion due to inadequate atrial L-to-R shunt)

• myocardial ischemia (decreased perfusion of aorta [= common coronary artery ] + coronary arteries):

  • cardiogenic shock, metabolic acidosis (when ductus arteriosus closes)

CXR:

• hypoplastic/normal/enlarged cardiac silhouette:

  • prominent right atrial border

  • absence of left ventricular silhouette

  • thymic atrophy

• interstitial + alveolar pulmonary edema (due to pulmonary venous hypertension with severely restrictive interatrial communication in 80%)

• normal pulmonary vasculature (with wide nonrestrictive interatrial communication in 20%)

OB-US (may be missed <22 weeks GA):

• small left ventricular cavity (apex of LV and RV should be at same level)

• hypoplastic ascending aorta

• aortic coarctation (in 80%)

• diastolic flow reversal in narrow ascending aorta is DIAGNOSTIC

ECHO:

• normal/enlarged LA

• slitlike/small/normal LV

• enlarged RA

• herniation + prolapse of foramen ovale flap into RA

• hypoplastic ascending aorta (<5 mm = aortic atresia)

• absent/grossly distorted mitral valve echoes

Angio:

• retrograde flow in ascending aorta + aortic arch + coronary arteries via PDA

• stringlike ascending aorta <6 mm in diameter

• massive enlargement of RV + RVOT

Prognosis:	almost 100% fatal by 6 weeks
Time of diagnosis:	32% pre-, 65% 1 4 days postnatally
Rx:	(1) Prostaglandin E1 (patency of ductus arteriosus) (2) Hypoventilation (increase in CO2 maintains high pulmonary vascular resistance) (3) Nitroprusside IV (decreases systemic vascular resistance) (4) Norwood procedure = palliative attempt (5) Cardiac transplant

Hypoplastic Right Ventricle

• = PULMONARY ATRESIA WITH INTACT VENTRICULAR SEPTUM

• = underdeveloped right ventricle due to pulmonary atresia in the presence of an intact interventricular septum

Type I	= small RV secondary to competent tricuspid valve (more common)
Type II	= normal/large RV secondary to incompetent tricuspid valve

Hemodynamics:

fetus:	L-to-R atrial shunt through foramen ovale; retrograde flow through ductus arteriosus into pulmonary vascular bed
neonate:	closure of ductus results in cyanosis, acidosis, death

• small right ventricular cavity (apex of RV + LV should be at same level)

• atresia of pulmonary valve

• hypoplastic proximal pulmonary artery

• secundum atrial septal defect (frequently associated)

Rx:

prostaglandin E1 infusion + valvotomy + systemic-pulmonary artery shunt

Idiopathic Dilatation of Pulmonary Trunk

= CONGENITAL ANEURYSM OF PULMONARY ARTERY

Age:

adolescence; M < F

• systolic ejection murmur (in most cases)

• asymptomatic

• dilated main pulmonary artery causing a round bulge at the mediastinal border simulating a mass

• normal peripheral pulmonary vascularity

• normal pulmonary arterial pulsations

• NO lateralization of pulmonary flow

Dx per exclusion:

• Absence of shunts, CHD, acquired disease

• Normal RV pressure

• No significant pressure gradient across pulmonic valve

Prognosis:	nonprogressive
DDx:	(1) Marfan syndrome (2) Takayasu arteritis

Interruption of Aortic Arch

= rare congenital anomaly as a common cause of death in the neonatal period

Trilogy:

(1) Interrupted aortic arch
(2) VSD
(3) PDA (pulmonary blood supplies lower part of body)

In 1/3 associated with:

• Bicuspid aortic valve

• Muscular subaortic stenosis

• ASD

• Truncus arteriosus

• Transposition

• Complete anomalous pulmonary venous return

• presents with CHF

Location:

Type A:	distal to left subclavian artery (42%)
Type B:	between left CCA and subclavian artery (53%) associated with: DiGeorge syndrome
Type C:	between innominate and left CCA (4%)

• dilatation of right atrium + ventricle

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• dilatation of pulmonary artery

• ascending aorta much smaller than pulmonary artery

• arch formed by pulmonary artery + ductus arteriosus gives the appearance of a low aortic arch

• aortic knob absent

• trachea in midline

• NO esophageal impression

• retrosternal clear space increased (small size of ascending aorta)

• increased pulmonary vascularity (L-to-R shunt)

Prognosis:

76% dead at end of 1st month

Interruption of Aortic Arch

Interruption Of Pulmonary Artery

= pulmonary trunk continues only as one large artery to one lung while systemic aortic collaterals supply the other side

Associated with:

CHD (particularly if interruption on left side):
1. Tetralogy of Fallot
2. Scimitar syndrome = congenital pulmonary venolobar syndrome
3. PDA, VSD
4. Pulmonary hypertension

Collateral supply:

• Arteries arising from arch + ascending aorta

• Bronchial vessels

• Intercostal vessels

• Branches from subclavian artery

Location:

usually opposite from aortic arch; R > L pulmonary artery

CXR:

• hypoplastic ipsilateral lung

• lung opacity similar to normal lung/slightly increased

• volume loss of affected hemithorax:

  • mediastinal shift toward involved lung

  • hemidiaphragm may be elevated

  • small hyperlucent ipsilateral chest with narrowed intercostal spaces

• hyperinflated contralateral lung with herniation into smaller hemithorax

• comma-shaped small distorted hilar shadow

• asymmetry of pulmonary vascularity

• normal respiratory motion (normal aeration of hypoplastic lung)

CECT:

• affected pulmonary artery completely absent/terminates within 1 cm of its origin

• serrated pleural thickening (= enlarged intercostal + transpleural arteries)

• multiple linear opacities perpendicular to pleural surface (= transpleural systemic vessels)

NUC:

• absent perfusion with normal aeration

Angio:

• absent pulmonary artery

Cx:	recurrent pulmonary infection, hemorrhage, hemoptysis (10%), mild exertional dyspnea, pulmonary hypertension (19 25%)
Rx:	surgical anastomosis between proximal + distal pulmonary artery (to prevent progressive pulmonary hypertension with dyspnea, cyanosis, hemoptysis, death)
DDx:	(1) Hemitruncus (2) Swyer-James syndrome (ipsilateral air trapping, reduced ventilation + perfusion) (3) Chronic thromboembolic occlusion (4) Takayasu arteritis (5) Mediastinal fibrosis (6) Hypogenetic lung syndrome (abnormal bronchial brancing pattern

Intravenous Drug Abuse

Complications secondary to:

• direct toxic effects of drugs or drug combinations (eg, heroin + cocaine/talwin)

• direct toxic effects of adulterants [eg, heroin is mixed ( cut ) with quinine, baking soda, sawdust]

• septic preparation

• injection technique

• choice of injection site (eg, groin hit into femoral vein; pocket shot into jugular, subclavian, brachiocephalic vein)

• Cardiovascular complications

  • Arterial pseudoaneurysm may be followed by rupture with exsanguination/loss of limb

  • Arteriovenous fistula

  • Arterial occlusion

    • at injection site due to intimal damage, thrombosis, spasm

    • distal to injection site due to embolization, spasm

  • Venous thrombosis

  • Intravenous migration of needle to heart/lungs

  • embolization of infectious agent/foreign body/air through inadvertent arterial injection ( hit the pink )

  • endocarditis (most commonly S. aureus)

• Soft-tissue complications

  • Hematoma/abscess

  • foreign bodies

  • Lymphadenopathy

  • Cellulitis

• Skeletal complications

  • Osteomyelitis

    • direct contamination: eg, pubic bone ( groin hit )/clavicle ( pocket shot )

    • hematogenous: spine most commonly affected

  P.642

  
  

  • Septic arthritis:

    • spine, sacroiliac, sternoclavicular, symphysis pubis, acromioclavicular, hip, knee, wrist

• Pleuropulmonary complications

  • Pneumothorax ( pocket shot )

  • Hemo-/pyothorax

  • Septic pulmonary emboli

• Gastrointestinal complications

  • Severe colonic ileus

  • Colonic pseudoobstruction

  • Necrotizing enterocolitis

  • Liver abscess

• Genitourinary complications

  • focal/segmental glomerulosclerosis (heroin abuser)

  • Amyloidosis

• CNS complications

  • Spinal epidural abscess in 5 18%(from vertebral osteomyelitis)

  • Cord compression (from collapsed vertebral body)

  • Cerebral infarction from subacute bacterial endocarditis, toxic effect of drug, spasm, intimal damage from pocket shot

  • Intracranial hemorrhage from trauma, hypertension, vasculitis, injection of anticholinergic drugs, rupture of mycotic aneurysm

  • Meningitis, cerebral abscess

Ischemic Heart Disease

= CORONARY ARTERY DISEASE (CAD)

Incidence:	1.5 million/year; leading cause of death in industrial nations
Morbidity:	28.7 cases per 1,000 men per year
Mortality:	3.1 deaths per 1,000 men per year

Noninvasive testing:

• Noninvasive testing is of marginal benefit when disease prevalence is <0.2/>0.7

• Concordant thallium-201 and stress ECG are greater predictors of disease probability than either one used alone and/or when discordant

• Sequential thallium-201 and stress ECG are most useful to establish the diagnosis of CAD when pretest prevalence is intermediate + test results are concordant

CXR:

• often normal

• coronary artery calcification

• pulmonary venous hypertension following acute infarction (40%)

• LV aneurysm

ECHO:

• region of dilatation with disturbance of wall movement

(1)	Akinesis = no wall motion
(2) Hypokinesis	= reduced wall motion
(3) Dyskinesis	= paradoxical systolic expansion
(4) Asynchrony	= disturbed temporal sequence of contraction

Coronary angiography:

1.2 million procedures per year

Kawasaki Syndrome

• = MUCOCUTANEOUS LYMPH NODE SYNDROME

• = acute febrile multisystem vasculitis of unknown cause involving large + medium-sized + small arteries with a predilection for the coronary arteries

Incidence:	average of 1.1:100,000 population per year
Histo:	panvasculitis
Age:	<5 years of age (in 85%); peak age of 1 2 years; M:F = 1.5:1
Associated with:	polyarthritis (30 50%), aseptic meningitis (25%), hepatitis (5 10%), pneumonitis (5 10%)

• fever >5 days

• mucosal reddening (injected fissured lips, injected pharynx, strawberry tongue) in 99%

• nonpurulent cervical lymphadenopathy (82%)

• maculopapular rash on extensor surfaces (99%)

• bilateral nonpurulent conjunctivitis (96%)

• erythema of palms + soles with desquamation (88%)

• @ Cardiovascular system (1/3)

  • Coronary artery abnormality (15 25%)

    • coronary artery aneurysm: LCA (2/3), RCA (1/3); proximal segment in 70%; 48% regress, 37% diminish in size

    • coronary artery stenosis (39%) due to thrombus formation in aneurysm + intimal thickening

    • coronary artery occlusion (8%) in aneurysms >9 mm

  • Myocarditis (25%)

  • Pericarditis

  • Valvulitis

  • Atrioventricular conduction disturbance

• intestinal pseudoobstruction

• transient gallbladder hydrops

Prognosis:	0.4 3% mortality (from myocardial infarction/myocarditis with congestive heart failure/rupture of coronary artery aneurysm)
Rx:	aspirin (100 mg/kg per day) + gamma globulin
DDx:	infantile polyarteritis

Leiomyosarcoma of Ivc

most common intravascular venous tumor

Path:

growth patterns: extravascular, intravascular, combined

• shortness of breath (decreased cardiac return)

• elevated liver functions, jaundice

• lower-extremity edema

• collateral pathways bypassing IVC: hemiazygos, azygos

• tumor extension from IVC into right atrium

US:

• blood flow in IVC/hepatic veins may be absent/reversed/turbulent (depending on degree of obstruction)

• tumor vascularity (DDx from thrombus)

CT:

• contrast enhancement of tumor

Cx:

Budd-Chiari syndrome (from sudden/gradual occlusion of hepatic veins/IVC/both)

DDx of tumor extension into right atrium:

• renal cell carcinoma, hepatocellular carcinoma

Lymphoma of heart

Secondary Cardiac Lymphoma

P.643

Incidence:

in 16 28% on autopsy; pericardial involvement more frequent; more common in immunocompromised patients

Primary Cardiac Lymphoma

• = lymphoma that involves only heart/pericardium at time of diagnosis (extremely rare)

Age:	13 90 (mean, 60) years
Predisposed:	immunocompromised patients, esp. AIDS
Path:	multiple firm nodules; contiguous invasion of pericardium
Histo:	typically NHL: well-differentiated B-cell lymphoma, follicular center cell lymphoma, diffuse large cell lymphoma, undifferentiated Burkitt-like lymphoma

• unresponsive rapidly progressive heart failure

• arrhythmia, cardiac tamponade, SVC syndrome

• chest pain

Location:

RA > RV > LV > LA > atrial septum > ventricular septum; >1 chamber (75%)

CXR:

• cardiomegaly

• signs of CHF

• massive pericardial effusion

ECHO:

• hypoechoic myocardial masses in RA/RV

• pericardial effusion

CT:

• hypo-/isoattenuating masses relative to myocardium

• heterogeneous enhancement of masses

MR:

• poorly marginated heterogeneous lesions of iso- to hypointensity relative to myocardium on T1WI

• lesions isointense to myocardium on T2WI

• heterogeneous enhancement with gadolinium

Dx:	positive cytology in pericardial fluid (in 67%); exploratory thoracotomy with biopsy of cardiac tissue
Prognosis:	very poor

Microscopic Polyangitis

• MICROSCOPIC POLYARTERITIS = HYPERSENSITIVITY VASCULITIS = LEUKOCYTOCLASTIC VASCULITIS

• pauci-immune necrotizing small-vessel angitis without granulomatous inflammation

Path:	necrotizing arteritis identical to polyarteritis nodosa but in vessels smaller than arteries (= arterioles, venules and capillaries)
Trigger:	drugs (eg, penicillin), microorganisms, heterologous proteins, tumor antigens

• hemoptysis, hematuria, proteinuria

• abdominal pain, GI bleeding, muscle pain + weakness

• ANCA (antineutrophil cytoplasmic autoantibodies) in >80%

• negative serologic tests for hepatitis B

Location:

skin, mucous membranes, lung, brain, heart, GI tract, kidney, muscle

• Most common cause of the pulmonary-renal syndrome!

• pulmonary infiltrates (due to capillaritis)

• glomerulonephritis (90%)

Rx:

removal of offending agent

Mitral Regurgitation

= MITRAL INSUFFICIENCY

Cause:

• ACUTE

  • Spontaneous rupture of chordae tendineae

  • Myocardial infarction with involvement of papillary muscle (posteromedial > anterolateral papillary muscle)

  • Bacterial endocarditis

  • Periprosthetic valve leak

• CHRONIC

  • Acute rheumatic fever

    • isolated: frequently seen in children

    • uncommon in adults (mostly combined with stenosis)

  • Mitral valve prolapse syndrome

  • Atrial myxoma

  • Coronary artery disease

  • Idiopathic hypertrophic subaortic stenosis (IHSS)

  • Myxomatous degeneration of mitral valve: eg, Marfan syndrome

  • Mitral annulus calcification

  • Functional/secondary (from dilatation of mitral ring in any condition with severe dilatation of LV)

  • Congenital heart disease: short/abnormally inserted chordae tendineae; persistent ostium primum ASD with cleft mitral valve, corrected transposition with Ebstein-like anomaly

Hemodynamics:

• backward flow of blood from LV into LA during LV systole; increased volume of blood under elevated pressure causes dilatation of LA; marked increase in LV diastolic volume with little increase in LV diastolic pressure (= increase in preload without increase in afterload = elevated ejection fraction)

• ACUTE MITRAL REGURGITATION

  • pulmonary venous hypertension with engorged pulmonary vessels and cephalization (less than with mitral stenosis)

  • symmetric interstitial/alveolar pulmonary edema:

    • asymmetric right upper lobe edema (9%) due to preferential flow of regurgitant jet into pulmonary vein of RUL (PATHOGNOMONIC)

  • limited cardiac enlargement

• CHRONIC MITRAL REGURGITATION

  • enlarged heart

  • massive LA:

    • LA posterior wall calcification (McCallum patch)

    • enlarged LA appendage (with history of previous rheumatic heart disease)

  • mitral annular calcification (frequent)

  • marked LV enlargement (cardiothoracic ratio >0.55) + LV failure

ECHO:

• LV volume overload:

  • normal-sized/enlarged LV

  • increased septal + posterior wall motion

• increased EF slope

• early closure of aortic valve (LV stroke volume partially lost to LA)

• LA enlargement (in chronic MV insufficiency)

• bulging of interatrial septum to the right during systole

P.644




• Doppler is only diagnostic tool + allows assessment of severity

Mitral Stenosis

Cause:

rheumatic heart disease (5 15 years after initial episode of rheumatic fever); carcinoid syndrome; eosinophilic endocarditis; rheumatoid arthritis; SLE; mass obstructing LV inflow (tumor, atrial myxoma, thrombus); congenital

• M:F = 1:8

Hemodynamics:

• rise in left atrial + pulmonary vascular pressure throughout systole and into diastole; compensatory dilation of LA + pulmonary venous hypertension; development of medial hypertrophy + intimal sclerosis in pulmonary arterioles leads to postcapillary pulmonary arterial hypertension; RV hypertrophy; tricuspid regurgitation; RV dilatation; right heart failure

May be associated with:

ASD = Lutembacher syndrome (in 0.6%) causing L-to-R shunt

• history of rheumatic fever (in 50%)

• dyspnea on exertion, orthopnea, paroxysmal nocturnal dyspnea

• atrial fibrillation

• systemic embolization from thrombosis of atrial appendage

Stages (according to degree of pulmonary venous hypertension):

Stage 1	:	loss of hilar angle, redistribution
Stage 2	:	interstitial edema
Stage 3	:	alveolar edema
Stage 4	:	hemosiderin deposits + ossification

• @ Left heart

  • enlarged LA wall calcification:

    • double density seen through right upper cardiac border (AP view)

    • bulge of superior posterior cardiac border below carina (lateral view)

    • splaying of mainstem bronchi

    • esophagus displaced toward right + posteriorly

    • dilated left atrial appendage (not present with retracting clot), in 90% associated with rheumatic heart disease

      • Dilatation of left atrial appendage + calcification = rheumatic heart disease!

  • calcification of valve leaflets in 60% of severe MS, usually >50 years of age (DDx: calcification of mitral annulus)

  • normal/undersized LV

  • small aorta (due to decrease of forward cardiac output)

• @ Right heart

  • prominent pulmonary artery segment (precapillary hypertension)

  • hypertrophy of RV

  • dilatation of RV (tricuspid insufficiency/pulmonary hypertension)

  • increase in cardiothoracic ratio

  • diminution of retrosternal clear space

  • IVC pushed backward (lateral view)

• @ Lung

  • pulmonary vascular cephalization = redistribution of pulmonary blood flow to upper lobes (postcapillary pressure 16 19 mm Hg)

  • interstitial pulmonary edema (postcapillary pressure 20 25 mm Hg)

    DDx:

    interstitial fibrosis/deposition of hemosiderin-laden macrophages (= brown induration ) of chronic mitral valve stenosis

  • alveolar edema (postcapillary pressure 25 30 mm Hg)

    DDx:

    diffuse alveolar hemorrhage = diffuse confluent acinar/ground-glass areas of increased opacity sparing the lung periphery (= window frame effect)

  • pulmonary hemosiderosis:

    • 1 3 mm ill-defined nodules

    • fine/coarse reticular areas of increased opacity with bias for middle and lower lungs

  • pulmonary ossification (3 13%) = densely calcified 1 3 5 mm nodules ( trabeculae) mainly in middle and lower lungs

ECHO:

• thickening of leaflets toward free edge (fibrosis, calcification)

• flattening of EF slope = MV remains open throughout diastole due to persistently high LA pressure (crude index of severity of MV stenosis)

• diastolic anterior tracking of pML in 80% (secondary to diastolic anterior pull by larger + more mobile aML)

• diastolic doming of MV leaflets

• commissure fusion = increased echodensity + decreased leaflet motion at level of commissure

• area reduction of MV orifice: normal within 4 6 cm²; mild narrowing with <2 cm²; severe narrowing with <1 cm² (reproducible to within 0.3 cm²)

• shortening + fibrosis of chordae tendineae

• abnormal septal motion = early diastolic dip of IVS due to rapid filling of RV (in severe MV stenosis)

• slowed LV filling pattern of small LV

• dilatation of LA (>5 cm increases risk of atrial fibrillation + left atrial thrombus)

• De opening amplitude reduced to <20 mm indicating loss of valve pliability (DDx: low cardiac output state)

• absent A-wave common (atrial fibrillation)

• increase in valve gradient + pressure halftime on Doppler

Rx:	(1) Commissurotomy if valves pliable + calcium absent + MV regurgitation absent (2) Valve replacement for symptomatic patients with severely stenotic valves
DDx:	(1) Pseudomitral stenosis in decreased LV compliance (decreased ef slope, normal leaflet thickness + motion) (2) Rheumatic mitral insufficiency (indistinguishable findings + evidence of LV volume overload) (3) LA myxoma (mass behind MV + in LA) (4) Low cardiac output (apparent small valve orifice)

Lutembacher Syndrome

• = rheumatic mitral valve stenosis + ASD

Mitral Valve Prolapse

Incidence:	2-6%of general population; 5-20%of young women;? autosomal dominant inheritance
Age:	commonly 14-30 years

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Cause:

• floppy mitral valve = elongation of cusps + chordae leading to redundant valve tissue, which prolapses into LA during systole

  • Associated with:

    • Skeletal abnormalities: scoliosis, straightening of thoracic spine, narrow anteroposterior chest dimension, pectus excavatum deformity of sternum

    • Barlow syndrome = straight back syndrome

    • Marfan syndrome

    • tricuspid valve prolapse

    • Long-standing ASD

    • Autosomal dominant polycystic kidney disease

• Secondary MV prolapse:

  • papillary muscle dysfunction, rupture of chordae tendineae, rheumatic mitral insufficiency, primary pulmonary hypertension, ostium secundum ASD

• arrhythmias, palpitation, chest pain, light-headedness, syncope

• responsible for midsystolic click + late systolic murmur (when associated with mitral regurgitation)

• LA not enlarged (unless associated with significant mitral regurgitation)

ECHO:

• interruption of CD line with bulge toward left atrium:

  • abrupt midsystolic posterior buckling of both leaflets (classic pattern)

  • hammocklike pansystolic posterior bowing of both leaflets

• multiple scallops on mitral valve leaflets (short-axis parasternal view)

• valve leaflets may appear thickened (myxomatous degeneration + valve redundancy)

• mitral valve leaflets passing >2 mm posterior to plane of mitral annulus (apical 4-chamber view)

• hyperactive atrioventricular groove

• mitral annulus may be dilated >4.7 cm²

DDx:

(1) Pericardial effusion (systolic posterior displacement of MV leaflets + entire heart)
(2) Bacterial endocarditis (mimicked by locally thickened + redundant leaflets)

Myocardial Infarction

Incidence:

1,500,000 per year in USA resulting in 500,000 deaths (50% occur in asymptomatic individuals)

• atrioventricular block (common with inferior wall infarction as AV nodal branch originates from RCA); complete heart block has worse prognosis because it indicates a large area of infarction

CXR:

• normal-sized heart (84 95%) in acute phase if previously normal

• cardiomegaly: high incidence of congestive heart failure with anterior wall infarction, multiple myocardial infarctions, double- and triple-vessel CAD, LV aneurysm

CECT:

• perfusion defect within 60 90 seconds after bolus injection

• delayed enhancement of infarcted tissue peaking at 10 15 minutes (due to accumulation of iodine in ischemic cells), size of enhanced area correlates well with size of infarct

MR:

• no change/mildly decreased signal intensity of myocardium on T1WI (= edema of myocardium)

• high-intensity focus in region of acute infarction on T2WI

• thinning of LV wall + decreased signal intensity on T2WI (in remote infarction)

• increased intracavitary signal (from slow flow caused by stasis of blood adjacent to infarcted myocardium)

CEMR:

• pooling of gadolinium within region of infarction (disproportionately slow washout) on delayed images 20 30 minutes post injection

• highlighting of infarcted tissue with contrast using magnetic susceptibility to selectively suppress signals from normal myocardium

Cx:

(myocardium is prone to rupture during 3rd 14th day post infarction)

Left Ventricular Failure (60 70%)

• cardiac shock = systolic pressure <90 mm Hg

• Signs of pulmonary venous hypertension are a good predictor of mortality (>30% if present, <10% if absent)

• progressive enlargement of heart

• haziness + indistinctness of pulmonary arteries

• increase in size of right descending pulmonary artery >17 mm

• pleural effusion

• septal lines

• perihilar peripheral parenchymal clouding

• alveolar pulmonary edema

Mortality:

30 50% with mild LV failure; 44% with pulmonary edema; 80 100% with cardiogenic shock; 8% in absence of LV failure

Ventricular Aneurysm (12 15% of survivors)

 

Myocardial Rupture (3.3%)

• occurs usually on 3rd 5th day post MI

• enlargement of heart (slow leakage of blood into pericardium)

Prognosis:

cause of death in 13% of all infarctions; almost 100% mortality

Rupture of Papillary Muscle (1%)

Cause:

infarction of posteromedial papillary muscle in inferior MI (common)/anterolateral papillary muscle in anterolateral MI (uncommon)

• sudden onset of massive mitral insufficiency

• unresponsive to medical management

• abrupt onset of severe persistent pulmonary edema

• asymmetric PVH in right upper lobe

• minimal LV enlargement/normal-sized heart

• NO dilatation of LA (immediate decompression into pulmonary veins)

Prognosis:

70% mortality within 24 hours; 80 90% within 2 weeks

Rupture of Interventricular Septum (0.5 2%)

• occurs usually within 4 21 days with rapid onset of L-to-R shunt

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• Swan-Ganz catheterization: increase in oxygen content of RV, capillary wedge pressure may be within normal limits

• right-sided cardiac enlargement

• engorgement of pulmonary vasculature:

• asymmetric PVH of right upper lobe

• NO pulmonary edema (DDx to ruptured papillary muscle)

Prognosis:

24% mortality within 24 hours; 87% within 2 months; >90% in 1 year

Dressler Syndrome (<4%)

• = POSTMYOCARDIAL INFARCTION SYNDROME

Etiology:	autoimmune reaction to myocardial infarction
Onset:	2 3 weeks (range 1 week several months) following infarction

• relapses occur as late as 2 years after initial episode

• pleuritic chest pain

• fever

• thickening of pericardium

• pericardial effusion

• pleural effusion

• pneumonitis

Right Ventricular Infarction

• Right ventricle involved in 33% of left inferior myocardial infarction

• decreased RV ejection fraction

• accumulation of Tc-99m pyrophosphate

Prognosis:	in 50% RV ejection fraction returns to normal within 10 days
Cx:	(1) cardiogenic shock (unusual) (2) elevation of RA pressure (3) decrease of pulmonary artery pressure

Myxoma

= most common benign primary cardiac tumor (true neoplasm) in adults, 40 50% of all cardiac tumors

Age:	11 82 (mean 50) years; 90% of patients are between ages 30 and 60 years; M:F = 1:1.7 to 1:4
Classification:	sporadic (most frequent); familial type (mean age of 24 years); complex type = Carney syndrome
Path:	(a) gelatinous, friable, papillary/villous pedunculated tumor (b) round/lobular smooth sessile tumor (25%) with firm surface No infiltration of underlying tissues!
Histo:	composed of myxoma cells (= ovoid nucleus with inconspicuous/large nucleoli + abundant eosinophilic cytoplasm)) forming rings/syncytia/cords; hypocellular amorphous acid mucopolysaccharide matrix in areas without fibrosis; covered by a mono-layer of endothelial cells (= endocardial tumor)
Size:	0.6 12 (mean, 5.7) cm

• short history + rapid progression

• dyspnea, chest pain

• constitutional symptoms (30%):

  • fever, myalgia, arthralgia, weight loss, lethargy

  • leukocytosis, anemia, elevated ESR, petechiae

  • hypergammaglobulinemia

• positional symptoms (ie, change with position) due to hemodynamic obstruction:

  • arrhythmia (20%), heart murmur

  • congestive heart failure (valve obstruction)

  • syncope

• embolization (30 40%) to CNS, coronary artery, aorta, kidney, spleen, extremities, pulmonary artery (caused by tumor fragments/accumulated thrombus)

Location:	left atrium (75 80%); right atrium (10 20%); ventricle (5%); biatrial (with growth through fossa ovalis)
Site:	attached to interatrial septum by small stalk in fossa ovalis (75%)/to wall of cardiac chambers/to valve surfaces; may protrude into ventricle causing partial obstruction of atrioventricular valve

• small myxomas produce no CXR findings

• cardiomegaly

• atrial obstruction (mimicking valvular stenosis)

• persistent defect in atrium/diastolic defect in ventricle

• LEFT ATRIAL MYXOMA (75 80%) with obstruction of mitral valve:

  • pulmonary venous hypertension:

    • pulmonary vascular redistribution

    • interstitial edema

  • enlargement of LA

  • NO enlargement of atrial appendage

  • ossific lung nodules

  Cx:

  systemic emboli (27%) in 50% to CNS (stroke/ mycotic aneurysm)

• RIGHT ATRIAL MYXOMA (10 20%) with obstruction of tricuspid valve:

  • tumor calcification: R > L

  • enlargement of RA

  • prominent SVC, IVC, azygos vein

  • decreased pulmonary vascularity

  • pleural effusion (occasionally)

  Cx:

  pulmonary emboli

ECHO: (2D-ECHO is study of choice)

• tumor attached by narrow stalk

• tumor mobility:

  • prolapse across AV valve during diastole

• tumor distensibility

• hyperechoic spherical mass:

  • internal hypoechoic areas (= hemorrhage, necrosis)

  • speckled echogenic foci (= calcifications)

  • frondlike surface projections

• Doppler:

  • valvular regurgitation

• M-mode findings of only historical interest:

  • dense echoes appearing posterior to aML soon after onset of diastole

  • pML obscured

  • tumor echoes can be traced into LA

  • dilated LA

  • reduced E-F slope

CT:

• well-defined spherical/ovoid intraluminal filling defect

• lobular/smooth surface contour

• tumor attenuation lower than unopacified blood (due to gelatinous component)

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• heterogeneous texture (due to hemorrhage, necrosis, cyst formation, fibrosis, calcification [16%], ossification)

MR:

• iso-/hypointense on T1WI relative to myocardium

• heterogeneous contrast enhancement (secondary to necrotic areas)

• markedly hyperintense on T2WI

• areas of decreased signal intensity (calcifications, hemosiderin deposits)

Rx:	urgent surgical excision valvuloplasty/valve replacement
Prognosis:	5 14% recurrence rate (multifocal myxomas)
DDx:	(1) Thrombus (most commonly in LA + LV) (2) Other cardiac tumors: sarcoma, malignant mesenchymoma, metastasis, papillary fibroelastoma (also arises from narrow stalk)

Carney Complex

• = CARNEY SYNDROME = COMPLEX MYOMA

• = autosomal-dominant inherited disorder

Prevalence:	7% of all myxomas; 150 patients identified since 1985 worldwide
Age:	younger than patients with sporadic myxoma

• endocrine overactivity:

  • Cushing syndrome

  • sexual precocity

  • acromegaly

• Cardiac myxomas: multifocal (66%), outside left atrium, recurring at an increased rate after resection

• Hyperpigmented skin lesions: lentigines, ephelides, blue nevi

• Myxoid fibroadenoma of the breast

• Psammomatous melanotic schwannoma

• Pituitary adenoma

• Testicular tumor: large-cell calcifying Sertoli cell tumor

• Primary pigmented nodular adrenocortical hyperplasia

N.B.:

not related to Carney triad (pulmonary hamartomas, extraadrenal paragangliomas, gastric leiomyosarcoma)

Papillary Fibroelastoma

• = FIBROELASTIC PAPILLOMA = PAPILLOMA/MYXOMA/FIBROMA OF VALVES = GIANT LAMBL EXCRESCENCE = MYXOFIBROMA = HYALINE FIBROMA

• = benign endocardial papilloma predominantly affecting cardiac valves

Prevalence:	25% of all cardiac valvular tumors (most common valvular tumor); 10% of all primary cardiac tumors (2nd most common primary benign cardiac neoplasm after myxoma)
Mean age:	60 years; M:F = 1:1
Cause:	? reactive process,? hamartoma
Path:	gelatinous mass with sea anemone appearance due to multiple delicate branching papillary fronds attached to endocardium by short pedicle
Histo:	avascular papilloma composed of fibrous core + lined by a single layer of endothelium; scattered smooth muscle cells within papillary projections

• mostly asymptomatic (incidental finding at autopsy, surgery, echocardiography, cardiac catheterization)

• chest pain, dyspnea, embolic events (TIA/stroke from thrombi collecting on tumor)

• NO valvular dysfunction

Location:	aortic (29%) > mitral (25%) > tricuspid (17%) > pulmonary valve (13%); nonvalvular endocardial surface of atrium/ventricle (16%)
Size:	<1 cm in diameter (may be as large as 5 cm)

ECHO:

• <1.5 cm homogeneous mobile pedunculated mass:

  • elongated strandlike projection/well-defined head

  • CHARACTERISTIC stippled edge with a shimmer/vibration at interface between tumor and surrounding blood (DDx: amorphous thrombus)

  • flutters/prolapses with cardiac motion

• turbulent blood flow

Rx:

surgical excision leaflet repair/valve replacement

Patent Ductus Arteriosus

PDA = persistence of left 6th aortic arch, which connects the left pulmonary artery with the descending aorta beyond the origin of the left subclavian artery

Incidence:	9% of all CHD; M:F = 1:2
Associated with:	prematurity, birth asphyxia, high-altitude births, rubella syndrome, coarctation, VSD, trisomy 18 + 21

Normal ductus physiology in mature infant:

• increase in arterial oxygen pressure leads to constriction + closure of duct

• Functional closure due to muscular contraction within 10 15 48 hours

• Anatomic closure due to subintimal fibrosis + thrombosis: in 35% by 2 weeks; in 90% by 2 months; in 99% by 1 year

Hemodynamics of PDA:

• increased volume of blood flows from aorta through PDA + pulmonary artery into lungs and then to left side of heart

• mostly asymptomatic

• congestive heart failure (rare) usually by 3 months of age if L-to-R shunt large

• continuous murmur

• bounding peripheral pulses (intraaortic pressure runoff through PDA)

CXR (mimics VSD):

• enlarged pulmonary artery segment

• increase of pulmonary vasculature; less flow directed to LUL

• enlarged ascending aorta + aortic arch (thymus may obscure this)

• LA + LV enlargement

• enlarged RV (only with pulmonary hypertension)

• prominent ductus infundibulum (diverticulum) = prominence between aortic knob + pulmonary artery segment

• obscured aortopulmonary window

• railroad track = calcified ductus arteriosus

ECHO:

• LA:Ao ratio 1.2:1 (signalizes significant L-to-R shunt)

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Angio:

• catheter course from RA to RV, main pulmonary artery, PDA, descending aorta

• communication from aorta (distal to left subclavian artery) to left pulmonary artery on AP/LAT/LAO aortogram

PDA in Premature Infant

• premature infant not subject to medial muscular hypertrophy of small pulmonary artery branches (which occurs in normal infants subsequent to progressive hypoxia in 3rd trimester)

• CHF

  • Cause:

    • pulmonary artery pressure remains low without opposing any L-to-R shunts (PDA/VSD)

    • ductus arteriosus remains open secondary to hypoxia in RDS

• recurrence of alveolar airspace filling after resolution of RDS

• granular pattern of hyaline membrane disease becomes more opaque

• enlargement of heart (masked by positive pressure ventilation)

Rx:

• Medical therapy:

  • supportive oxygen, diuretics, digitalis

  • avoid fluid overload (not to increase shunt volume)

  • antiprostaglandins = indomethacin opposes prostaglandins, which are potent duct dilators

• Surgical ligation

Beneficial PDA

• = compensatory effect of PDA in:

• Tetralogy of Fallot

  • cyanosis usually occurs during closure of duct shortly after birth

• Eisenmenger pulmonary hypertension

  • PDA acts as escape valve shunting blood to descending aorta

• Interrupted aortic arch

  • supply of lower extremity via PDA

Nonbeneficial PDA

• in L-to-R shunts (VSD, aortopulmonic window) a PDA increases shunt volume

Penetrating Aortic Ulcer

• = PENETRATING ATHEROSCLEROTIC ULCER OF THE AORTA

• = atheromatous intimal plaque characterized by ulceration that penetrates deep into the internal elastic lamina + reaches the media

Incidence:	uncommon
Age:	elderly with hypertension, hyperlipidemia and severe atherosclerosis

• often asymptomatic

• chest pain that may radiate to back (WITHOUT pulse difference, aortic regurgitation, CNS symptoms)

• occasional distal ischemia due to embolic event

Location:

middle/distal third of descending thoracic aorta (31%); occasionally abdominal aorta; may occur anywhere in aorta

• extensive atherosclerotic disease + ectasia

• lack of compression of the aortic lumen

• intramural hematoma

• NO intimal flap

CECT:

• focally ulcerated plaque

• adjacent subintimal hematoma (differentiation from intraluminal thrombus/atherosclerotic plaque not possible):

  • inward displacement of calcified intima (common)

• thickening/enhancement of adjacent aortic wall

MR (valuable for patients in renal failure):

• focal excavation of aortic wall

• subacute hematoma in aortic wall of high signal intensity on T1WI + T2WI (methemoglobin) either localized or mimicking type 3 dissection

Angio:

• ulcerated atherosclerotic plaque

• aortic wall thickening

Cx:

• Aortic dissection (2 to hemorrhage within media; controversial):

  • localized/extensive

  • communicating double-barreled /thrombosed

• Saccular/fusiform aortic aneurysm (2 to stretching of aortic wall)

• Aortic rupture (40% risk compared with 7% risk in aortic dissection)

Rx:	(1) antihypertensive medication, analgesics (2) excision of ulcer + aortic interposition graft (for patients with recurrent symptoms/pseudoaneurysm formation)
DDx:	(1) Aortic dissection (intimal flap, patent false lumen) (2) Atheroma/chronic intramural thrombus (low signal intensity on T1WI + T2WI)

Pericardial Defect

• failure of pericardial development secondary to premature atrophy of the left duct of Cuvier (cardinal vein), which fails to nourish the left pleuropericardial membrane

Frequency:	1:13,000; M:F = 3:1
Age at detection:	newborn to 81 years (mean 21 years)

Location:

• PARTIAL ABSENCE (91%)

  (a) complete absence on left side	(35%)
  (b) foraminal defect on left side	(35%)
  (c) diaphragmatic pericardial aplasia	(17%)
  (d) foraminal defect on right side	(4%)

• TOTAL BILATERAL ABSENCE (9%)

In 30% associated with:

• Bronchogenic cyst (30%)

• VSD, PDA, mitral stenosis

• Diaphragmatic hernia, sequestration

• mostly asymptomatic

• palpitations, tachycardia, dyspnea, dizziness, syncope

• positional discomfort while lying on left side

• nonspecific intermittent chest pain (lack of pericardial cushioning, torsion of great vessels, tension on pleuropericardial adhesions, pressure on coronary arteries by rim of pericardial defect)

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• ECG: right axis deviation, right bundle branch block

• size:

  small foraminal defect	=	no abnormality
  large defect	=	herniation of cardiac structures/lung
  complete absence	=	levoposition of heart

• absence of left pericardial fat-pad

• levoposition of heart with lack of visualization of right heart border

• prominence/focal bulge in the area of RVOT, main pulmonary artery, left atrial appendage

• sharp margination + elongation of left heart border

• insinuation of lung between heart + left hemidiaphragm

• insinuation of lung between aortic knob + pulmonary a.

• increased distance between heart + sternum secondary to absence of sternopericardial ligament (cross-table lateral projection)

• pneumopericardium following pneumothorax

• NO tracheal deviation

Cx:	cardiac strangulation
Rx:	foraminal defect requires surgery because of (a) herniation + strangulation of left atrial appendage, (b) herniation of LA/LV (1) Closure of defect with pleural flap (2) Resection of pericardium

Pericardial Mesothelioma

= malignant primary neoplasm arising from mesothelial cells of the pericardium

Incidence:	<1% of all mesotheliomas; 50% of all primary pericardial tumors
Age:	2 78 (mean, 46) years; M:F = 2:1
Path:	multiple coalescing pericardial masses with obliteration of pericardial space; myocardial invasion is rare
Histo:	biphasic tumor composed of epithelial areas forming tubulopapillary structures (resembling carcinoma) and spindled areas (resembling sarcoma)

• chest pain, cough, dyspnea, palpitations

• signs of pericarditis, cardiac tamponade

• irregular diffuse pericardial thickening

• cardiac encasement by soft-tissue masses

• pericardial effusion

CXR:

• cardiac enlargement with irregular contour

• diffuse mediastinal enlargement

Rx:	palliative surgery + radiation therapy
Prognosis:	6 12-month survival after diagnosis

Pericardial Teratoma

= benign germ cell neoplasm

Age:	infants + children
Histo:	derivatives of all 3 germ cell layers (neuroglia, cartilage, skeletal muscle, liver, intestine, pancreas, glandular tissue)
Location:	within pericardial sac connected to a great vessel via a pedicle; intramyocardial (rare)

• respiratory distress, cyanosis (due to pericardial tamponade + compression of SVC, RA, aortic root, PA)

CXR:

• enlarged cardiomediastinal silhouette

• formed calcified teeth

US:

• intrapericardial heterogeneous complex multilocular cystic mass:

  • intrinsic echogenic foci (= calcifications)

• pericardial effusion

• fetal hydrops (ascites, pleural effusion, subcutaneous edema, polyhydramnios)

MR:

• large mass of heterogeneous signal intensity

Rx:	emergent pericardiocentesis (life-threatening lesion); urgent surgical excision
Prognosis:	good

Persistent Fetal Circulation

• = PERSISTENT PULMONARY HYPERTENSION OF THE NEWBORN

• = delay in transition from intra- to extrauterine pulmonary circulation

Cause:

primary disorder related to birth asphyxia, concurrent parenchymal lung disease (meconium aspiration, pneumonia, pulmonary hemorrhage, hyaline membrane disease, pulmonary hypoplasia), concurrent cardiovascular disease, hypoxic myocardial injury, hyperviscosity syndromes)

• labile PO₂

• structurally normal heart

Polyarteritis Nodosa

• = PERIARTERITIS NODOSA = PAN

• = systemic fibrinoid necrotizing inflammation of medium-sized + small muscular arteries without glomerulo-nephritis or vasculitis in arterioles, capillaries, venules

Frequency:	4 9 cases/million/year (rare); 70 per million/year in patients with hepatitis B; M:F = 2:1
Etiology:	? deposition of immune complexes
Age:	18 81 (mean age, 55) years
Path:	focal panmural necrotizing vasculitis; mucoid degeneration + fibrinoid necrosis begins within media; absence of vasculitis in vessels other than arteries (DDx: necrotizing angitis, mycotic aneurysm)
Histo:	polymorphonuclear cell infiltrate in all layers of arterial wall + perivascular tissue (acute phase), mononuclear cell infiltrate, intimal proliferation, thrombosis, perivascular inflammation (chronic stage)
Associated with:	hepatitis B + HIV antigenemia

• low-grade fever, malaise, abdominal pain, weight loss

• elevated ESR, thrombocytosis, anemia

• positive for hepatitis B surface antigen (up to 30%)

• positive perinuclear ANCA titers

Location:

all organs may be involved, kidney (70 90%), heart (65%), liver (50 60%), spleen (45%), pancreas (25 35%), GI tract, CNS (cerebrovascular accident, seizure), skin

• @ Kidney (involved in 70 80 90%)

  • painless hematuria

  • irregular nephrogram

  • radiolucent cortical areas

  • prolonged washout of contrast material

  P.650

  
  

  • multiple small intrarenal microaneurysms (at bifurcation of interlobar/arcuate arteries)

  • aneurysms may disappear (thrombosis) or appear in new locations

  • arterial narrowing + thrombosis (chronic stage/healing stage)

  • multiple small cortical infarcts

  • CECT:

    • lobulated renal contour + irregular thinning (due to prior cortical infarcts)

    • multiple hypoattenuating bands (arterial occlusion)

  Cx:

  intrarenal/subcapsular/perinephric hemorrhage (rupture of aneurysm)

• @ Chest (involved in 70%)

  • CHF, myocardial infarction

  • cardiac enlargement/pericardial effusion (14%)

  • pleural effusion (14%)

  • pulmonary venous engorgement (21%)

  • massive pulmonary edema (4%)

  • linear densities/platelike atelectasis (10%)

  • wedge-shaped/round peripheral infiltrates of nonsegmental distribution (14%) (simulating thromboembolic disease with infarction)

  • cavitation may occur

  • interstitial lower lung field pneumonitis

• @ Liver (50 66%)

  • prolonged washout of contrast material (due to increase in peripheral hepatic arterial resistance + hepatic infarcts

• @ GI tract (50 70%)

  Location:

  small intestine > mesentery > colon

  • abdominal pain, nausea, vomiting (66%)

  • ulcer formation, GI bleeding (6%)

  • bowel perforation (5%), intestinal infarction (1.4%)

• @ Skeletal muscle (39%)

  • myalgia, arthralgia (50%), limb claudication

  • aneurysms of lumbar + intercostal arteries (19%)

  • lower extremity ischemia (16%)

• @ Skin (20%)

  • palpable purpura, infection, ischemic ulcer

  • tender subcutaneous nodules (15%)

  • peripheral neuropathy (= mononeuritis multiplex)

Angiography (61 89% sensitive, 90% specific, 55% PPV, 98% NPV, 80% true-positive rate):

• multiple (>10) aneurysms of small + medium-sized arteries typically at branching points as a result of pannecrosis of the internal elastic lamina in 50 60% (HALLMARK):

  • 1 5 mm saccular aneurysms in 60 75%

  • fusiform aneurysms/arterial ectasia

  • Aneurysms are found in 12 94% of patients with polyarteritis nodosa

• luminal irregularities (in up to 90%)

• stenoses of arteries

• arterial occlusions + organ infarcts (98%)

DDx:	rheumatoid vasculitis, drug abuse, systemic lupus erythematosus, Churg-Strauss syndrome
Dx:	angiography, tissue biopsy
Cx:	renin-mediated hypertension, renal failure, hemorrhage secondary to aneurysm rupture (9%), organ infarction due to vessel thrombosis, gangrene of fingers/toes
Prognosis:	clinical course lasts several months to >1 year; relapse in 40% with median interval of 33 months; 13% 5-year survival rate if untreated
Rx:	immunosuppression with corticosteroids + cyclophosphamide (increases 5-year survival rate to 48 90%)

Popliteal Artery Entrapment Syndrome

• = popliteal artery classically winding medially and then inferiorly to the tendinous insertion of the medial head of the gastrocnemius

Incidence:	35 cases in American surgical literature; bilateral in up to 66%
Cause:	anomalous development and course of medial head of gastrocnemius muscle, which attaches to medial femoral condyle after development of primitive popliteal artery in 20-mm embryo slinging around lateral aspect of popliteal a.

Pathophysiology:

• flow unimpeded when muscle relaxed; increased arterial angulation with muscle contraction (early); progressive intimal hyperplasia ( atheroma = misnomer) due to microtrauma in area of repeated arterial compression; ultimately occlusion/thrombosis within aneurysm (late)

Age:

<35 years in 68%; age peaks at 17 and 47 years; M:f = 9:1

• slowly progressive intermittent unilateral calf claudication (early) esp. during periods of prolonged standing

• acute ischemia of leg with permanent occlusion of popliteal a. (late)

• posterior tibial pulse obliterated during active plantar flexion against resistance

• PVR has 40% false-positive results

• ankle-arm index reduced during active muscle contraction

• Doppler waveforms of posterior tibial a. diminished during muscle contractions

Angio (biplanar views with hyperextended knee):

• medial deviation of artery (29%), popliteal stenosis (11%), poststenotic dilatation (8%)

Dx:

• arteriography with typical medial deviation of popliteal a. before + after gastrocnemius contraction

• popliteal a. thrombosis/occlusion

Cx:	popliteal a. aneurysm
DDx:	cystic adventitial disease of popliteal a., arterial embolism, premature arteriosclerosis, popliteal aneurysm with thrombosis, popliteal a. trauma, popliteal a. thrombosis, Buerger disease, spinal cord stenosis (= neurogenic claudication)

Primary Pulmonary Hypertension

• = PLEXOGENIC PULMONARY ARTERIOPATHY

Diagnosis per exclusion:

• clinically unexplained progressive pulmonary arterial hypertension without evidence for thromboembolic disease/pulmonary venoocclusive disease

P.651

At risk:	portal hypertension (with/without liver disease), collagen vascular disease, HIV infection, aminorex fumarate (appetite suppressant) ingestion
Histo:	plexiform + angiomatoid lesions = tortuous channels within glomeruloid proliferation of endothelial cells (75%); acute + organizing thrombi (50%)
Age:	3rd decade; M:F = 1:3

• gradual onset of progressive dyspnea (60%)

• easy fatigability, syncope, angina

• hyperventilation, hemoptysis

• Raynaud phenomenon

• right ventricular enlargement (hypertrophy + dilatation)

• dilatation of central pulmonary arteries

CXR:

• prominent central pulmonary arteries:

  • enlarged pulmonary trunk

  • right descending pulmonary artery >25 mm wide

• pulmonary vascularity:

  • oligemia + rapidly tapering vessels

  • overcirculation + vascular distension

CT:

• enlargement of central pulmonary arteries:

  • diameter of main pulmonary artery > 29 mm (87% sensitive, 89% specific) measured at scan plane of bifurcation at right angle to its long axis just lateral to ascending aorta

  • segmental artery-to-bronchus ratio >1:1

  • pulmonary artery-to-aorta ratio (rPA) >1

• abruptly diminished caliber of peripheral pulmonary vessels (at outer to medial third of lung mantle)

HRCT:

• mosaic pattern of lung attenuation (due to regional variations in lung perfusion):

  • hyperdense areas contain large caliber vessels

  • hypodense areas contain small caliber vessels

MR:

• reversal of interventricular septal curvature

• direct linear correlation between mean pulmonary artery pressure (PAP) and ratio of main pulmonary artery caliber to descending aorta (MPA/AO)

• abnormal intravascular signal (due to slow arterial flow caused by pulmonary vascular resistance) in 92% on gated T1WI

NUC:

• normal/low-probability V/Q scans

Angio:

• symmetrically enlarged central arteries

• diffuse pattern of abruptly tapering + pruned subsegmental vessels

• filamentous/ corkscrew peripheral arteries

• subpleural collaterals (occasionally)

Prognosis:	death in 2 5 years
Rx:	vasodilators, calcium channel blockers, diuretics, anticoagulants; lung/heart-lung transplantation

Pseudocoarctat

• AORTIC KINKING

• elongated redundant thoracic aorta with acute kink/anterior buckling just distal to origin of left subclavian artery at lig. arteriosum

• variant of coarctation without a pressure gradient

Age:

12 64 years

Associated with:

• hypertension, bicuspid aortic valve, PDA, VSD, aortic/subaortic stenosis, single ventricle, ASD, anomalies of aortic arch branches

• asymptomatic

• ejection murmur

• NO pressure gradient across the buckled segment

• anteromedial deviation of aorta

• chimney-shaped high aortic arch (in children)

• rounded/oval soft-tissue mass in left paratracheal region + superior to presumed normally positioned aortic arch [secondary to elongation of ascending aorta + aortic arch] (in adults)

• anterior displacement of esophagus

• NO rib notching/dilatation of brachiocephalic arteries/LV enlargement/poststenotic dilatation

Angio:

• high position of aortic arch

• figure 3 sign = notch in descending aorta at attachment of short ligamentum arteriosum

DDx:

true coarctation, aneurysm, mediastinal mass

Pulmonary Artery Pseudoaneurysm

tear/disruption of layers of vessel wall with extravasation of blood contained by adventitia/clot/compressed surrounding tissue

Incidence:

rare

Cause:

• TRAUMA

  • Improper placement of Swan-Ganz catheter

  • Penetrating/blunt (rare) trauma

• INFECTION:

  • Mycotic aneurysm (endovascular seeding from endocarditis, direct extension from necrotizing pneumonia)

  • Mycobacterial aneurysm (Rasmussen aneurysm)

  • Syphilitic aneurysm

• VASCULAR ABNORMALITY: cystic medial necrosis, Beh et disease, Marfan syndrome, Takayasu disease

• OTHER: septic emboli, neoplasm

Associated with:

CHD (patent ductus arteriosus)

• hemoptysis (= leakage of blood into bronchial tree)

CXR:

• stable/increasing focal lung mass

CT:

• enhancing round lung mass isointense to central pulmonary artery

Cx:

100% mortality with rupture

Pulmonary Atresia

• = CONGENITAL ABSENCE OF PULMONARY ARTERY

• = atretic pulmonary valve with underdeveloped pulmonary artery distally

May be associated with:

hypogenetic lung

CXR:

• small hemithorax of normal radiodensity

• mediastinal shift to affected side

• elevation of ipsilateral diaphragm

• reticular network of vessels on affected side (due to systemic collateral circulation from bronchial arteries)

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• rib notching from prominence of intercostal arteries (due to large transpleural collateral vessels)

OB-US:

• small/enlarged/normal right ventricle

• progressive atrial enlargement (tricuspid regurgitation)

• flow reversal in ductus arteriosus + main pulmonary artery (most reliable)

Pulmonary Atresia with Intact Interventricular Septum

Associated with:	ASD (R-to-L shunt)
Type I:	no remaining RV, no tricuspid regurgitation moderately enlarged RA (depending on size of ASD)
Type II:	normal RV with tricuspid regurgitation massive enlargement of RA

• cardiomegaly (LV, RA)

• concave/small pulmonary artery segment

• diminished pulmonary vascularity

Pulmonary Venoocclusive Disease

= fibrous narrowing of intrapulmonary veins; the postcapillary counterpart of primary pulmonary hypertension

Cause:

idiopathic (rare condition); venous thrombosis initiated by infection/toxic exposure/immune complex deposition

May be associated with:

• pregnancy, transplantation, drug toxicity (carmustine, bleomycin, mitomycin)

Hemodynamics:

• elevated pressure in right atrium + pulmonary artery

• decreased cardiac output

• normal/variably elevated capillary wedge pressures

• normal pressure in left atrium + left ventricle (excludes cardiac disease as the cause for venous hypertension)

Age:

children (33%), adolescents; M:F = 1:1

Histo:

• specific changes: webs, recanalized thrombus (in up to 95%), intimal fibrosis of pulmonary veins; capillary hemangiomatosis = sheets and nodular collections of thin-walled capillaries invading pulmonary arteries + veins + bronchioles + pleura

• nonspecific changes of venous hypertension: venous medial hypertrophy, septal edema + fibrosis, paraseptal venous infarction, interstitial + pleural lymphatic dilatation, intraalveolar hemosiderin-laden macrophages

• progressive dyspnea, hemoptysis

• antecedent flulike symptoms

CXR:

• pulmonary arterial hypertension

• diffuse interstitial pulmonary edema

• normal-sized left atrium

• mediastinal lymphadenopathy

CT:

• markedly small central pulmonary veins

• central and gravity-dependent parenchymal ground-glass attenuation

• smoothly thickened interlobular septa

• pleural effusions

• normal-sized left atrium

• centrilobular nodules

NUC:

• patchy distribution of Tc-99m MAA (of upstream pulmonary arterial hypertension)

Angio:

• enlarged right ventricle + central pulmonary arteries

• prolonged parenchymal phase enhancement

• delayed filling of normal pulmonary veins

• normal to small left atrium

Prognosis:	death within 3 years (no effective therapy)
Cx:	potentially fatal pulmonary edema following administration of vasodilators for presumed precapillary pulmonary hypertension
Dx:	often missed initially (clinical presentation + radiographic findings mimic interstitial lung disease)

Pulmonic Stenosis

Frequency:	pulmonary artery stenosis without VSD in 8% of all CHD
Embryology:	infundibulum formed from proximal portion of bulbis cordis; pulmonary valves develop in 6 9th week from outgrowth of 3 tubercles

• mostly asymptomatic

• cyanosis/heart failure

• loud systolic ejection murmur

• systolic doming of pulmonary valve (= incomplete opening)

• normal/diminished/increased pulmonary vascularity (depending on presence + nature of associated malformations)

• enlarged pulmonary trunk + left pulmonary artery (poststenotic dilatation)

• prominent left pulmonary artery + normal right pulmonary artery

• hypertrophy of RV with reduced size of RV chamber:

  • elevation of cardiac apex

  • increased convexity of anterior cardiac border on LAO

  • diminution of retrosternal clear space

• cor pulmonale

• mild enlargement of LA (reason unknown)

• calcification of pulmonary valves in older adults (rare)

Prognosis:

death at mean age of 21 years if untreated

Subvalvular Pulmonic Stenosis

• INFUNDIBULAR PULMONIC STENOSIS

  • typically in tetralogy of Fallot

• SUBINFUNDIBULAR PULMONIC STENOSIS

  • = hypertrophied anomalous muscle bundles crossing portions of RV

Associated with:	VSD (73 85%)
(a) low type:	courses diagonally from low anterior septal side to crista posteriorly
(b) high type:	horizontal defect across RV below infundibulum

• no dilatation of PA because of dissipation of RV force through elongated area of obstruction

Valvular Pulmonic Stenosis

• CLASSIC/TYPICAL PULMONIC VALVE STENOSIS (95%)

  • = commissural fusion of pulmonary cusps

    Age of presentation:

    childhood

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  • pulmonic click

  • ECG: hypertrophy of RV

  • thin mobile dome-shaped valve

  • jet of contrast through small central orifice

  • dilated main + left pulmonary artery

  Rx:

  balloon valvuloplasty

• DYSPLASTIC PULMONIC VALVE STENOSIS (5%)

  • = thickened redundant distorted cusps, immobile secondary to myxomatous tissue

  • NO click

  • NO poststenotic dilatation

    Rx:	surgical resection of redundant valve tissue
    Hemodynamics:	obstruction of RV systolic ejection with pressure burden on RV

    

  • CXR:

  • normal pulmonary vascularity

  • normal-sized heart

  Angio:

  • increase in trabecular pattern of RV

  • hypertrophied crista supraventricularis (lateral projection)

Supravalvular Pulmonic Stenosis

• 60% of all pulmonic valve stenoses

Site of narrowing:

pulmonary trunk, pulmonary bifurcation, one/both main pulmonary arteries, lobar pulmonary artery, segmental pulmonary artery

Shape of narrowing:

• localized with poststenotic dilatation

• long tubular hypoplasia

May be associated with:

• Valvular pulmonic stenosis, supravalvular aortic stenosis, VSD, PDA, systemic arterial stenoses

• Familial peripheral pulmonic stenoses + supravalvular aortic stenosis

• Williams-Beuren syndrome: PS, supravalvular AS, peculiar facies

• Ehlers-Danlos syndrome

• Postrubella syndrome: peripheral pulmonic stenoses, valvular pulmonic stenosis, PDA, low birth weight, deafness, cataract, mental retardation

• Tetralogy of Fallot/critical valvular pulmonic stenosis

Peripheral Pulmonary Artery Stenosis

Frequency:

5% of all pulmonary artery stenoses with an intact ventricular septum

Raynaud syndrome

• episodic digital ischemia in response to cold/emotional stimuli

• Pathogenesis:

  • increase in vasoconstrictor tone

  • low blood pressure

  • slight increase in blood viscosity

  • immunologic factors (4 81%)

  • cold provocation

  • exaggerated response of digit to cold/emotional stress:

    • numbness + loss of tactile perception

    • demarcated pallor/cyanosis

  • hyperemic throbbing during rewarming

  • sclerodactyly

  • small painful ulcers at tip of digit

Raynaud Disease

• = PRIMARY VASOSPASM = SPASTIC FORM OF RAYNAUD SYNDROME

• = exaggerated cold-induced constriction of smooth muscle cells in otherwise normal artery

Cause:	? acquired adrenoreceptor hypersensitivity
May be associated with:	reflex sympathetic dystrophy, early stages of autoimmune disorders
Age:	most common in young women

• usually affects all fingers of both hands equally

• normal segmental arm + digit pressures at room temperature

• peaked digit volume pulse = rapid rise in systole, anacrotic notch just before the peak, dicrotic notch high on the downslope

PPG:

• flat-line tracing at low temperatures (10 22 C) with sudden reappearance of normal waveform at 24 26 C = threshold phenomenon

Raynaud Phenomenon

• = SECONDARY VASOSPASM WITH OBSTRUCTION = OBSTRUCTIVE FORM OF RAYNAUD SYNDROME

• = digital artery occlusion due to stenotic process in normally constricting artery/associated with an abnormally high blood viscosity

• Cause:

  • Atherosclerosis (most frequent)

    • embolization from an upstream lesion

    • occlusion of major arteries supplying arm

  • Arterial trauma

  • End stage of many autoimmune disorders: eg, scleroderma, rheumatoid arthritis, systemic lupus erythematosus

  • Takayasu disease

  • Buerger disease

  • Drug intoxication (ergot, methysergide)

  • Dysproteinemia

  • Primary pulmonary hypertension

  • Myxedema

• normal vasoconstrictive response to cold

• reduced segmental arm + digit pressures at room temperature

• PPG (76% sensitivity, 92% specificity):

  • flat-line/barely detectable tracing at low temperature with gradual increase of amplitude upon rewarming

• Hand magnification angiography:

  • Baseline angiogram with ambient temperature

  • Stress angiogram immediately following immersion of hand in ice water for 20 seconds

Rhabdomyoma Of Heart

= benign myocardial hamartoma

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Prevalence:	most common cardiac tumor in infancy + childhood (up to 90%)
Age:	usually discovered <1 year of age
Path:	well-circumscribed intramural lobulated nodule/multiple <1 mm nodules (= rhabdomyomatosis)
Histo:	spider cells = enlarged vacuolated cells with high glycogen content + central nucleus surrounded by clear cytoplasm and radial extensions
Associated with:	tuberous sclerosis (in 50 86%); congenital heart disease

• asymptomatic (incidental detection at prenatal US/screening)

• murmur, arrhythmia

• heart failure (secondary to obstruction of outflow tract/reduction of enddiastolic volume/decreased contractility)

• supraventricular tachycardia (accessory conductive pathways within tumor)

Location:	usually multiple; ventricular wall with intramural growth + tendency to involve interventricular septum; atrial wall (rare)
Size:	up to 10 cm in diameter (average 3 4 cm)

US (good for small intramural lesions):

• fetal nonimmune hydrops

• solid echogenic sessile mass intracavitary component bulging into ventricular outflow tract/atrioventricular valve

• diffuse myocardial thickening (with multiple small lesions)

MR (complimentary to US):

• tumor isointense on T1WI + hyperintense to myocardium on T2WI

Prognosis:	may regress spontaneously in patients <4 years of age
Rx:	surgical excision for life-threatening symptoms
DDx:	fibroma (solitary centrally calcified + cystic tumor, in ventricular myocardium, associated with Gorlin syndrome), teratoma (single intrapericardial multicystic mass), hemangioma (arise from right atrium, pericardial effusion, skin hemangiomas)

Single Ventricle

• univentricular HEART = DOUBLE INLET SINGLE VENTRICLE

• failure of development of interventricular septum absence of one atrioventricular valve (mitral/tricuspid atresia) aortic/pulmonic stenosis

Associated with:

TGV or DORV

• conduction defect (aberrant anatomy of conduction system)

• two atrioventricular valves connected to a main ventricular chamber

• the single ventricle may be a LV (85%)/RV/undetermined

• a second rudimentary ventricular chamber may be present, which is located anteriorly (in left univentricle)/posteriorly (in right univentricle):

  • rudimentary chamber connection to one great artery

• may be associated with tricuspid/mitral atresia

Sinus Of Valsalva Aneurysm

deficiency between aortic media + annulus fibrosis of aortic valve resulting in distension + eventual aneurysm formation

Age:	puberty to 30 years of age
Site:	right sinus/noncoronary sinus (>90%) Right sinus usually ruptures into RV, occasionally into RA Noncoronary sinus ruptures into RA

• sudden retrosternal pain, dyspnea, continuous murmur

• shunt vascularity

• cardiomegaly

• prominent ascending aorta

Splenic Artery Aneurysm

= most frequent of visceral artery aneurysms

Etiology:	medial degeneration with superimposed atherosclerosis, congenital, mycotic, pancreatitis, trauma, portal hypertension (7 10% of cases due to high flow rate)
Predisposed:	women with 2 pregnancies (88%)
May be associated with:	fibromuscular disease (in 20%) M:F = 1:2

• usually asymptomatic

• pain, GI bleeding

Location:

intra-/extrasplenic

• calcified wall of aneurysm (2/3)

Cx:	rupture of aneurysm (6 9%, higher during pregnancy) especially if >1.5 cm in diameter
Mortality:	up to 76%
DDx:	renal artery aneurysm, tortuous splenic artery

Subclavian Steal Syndrome

= stenosis/obstruction of subclavian artery near its origin with flow reversal in ipsilateral vertebral artery at the expense of the cerebral circulation

Incidence:

2.5% of all extracranial arterial occlusions

Etiology:

• congenital: interruption of aortic arch, preductal infantile coarctation, hypoplasia of left aortic arch, hypoplasia/atresia/stenosis of an anomalous left subclavian artery with right aortic arch, coarctation with aberrant subclavian artery arising distal to the coarctation

• acquired: atherosclerosis (94%), dissecting aneurysm, chest trauma, embolism, tumor thrombosis, inflammatory arteritis (Takayasu, syphilitic), ligation of subclavian artery in Blalock-Taussig shunt, complication of coarctation repair, radiation fibrosis

Age:	average 59 61 years; M:F = 3:1; Whites:Blacks = 8:2
Associated with:	additional lesions of extracranial arteries in 81%

• lower systolic blood pressure by >20 40 mm Hg on affected side

• delayed weak/absent pulse in ipsilateral extremity

• signs of vertebrobasilar insufficiency (40%):

  • syncopal episodes initiated by exercising the ischemic arm

  • headaches, nausea, vertigo, ataxia

  • mono-, hemi-, para-, quadriparesis, paralysis

  • diplopia, dysphagia, dysarthria, paresthesias around mouth

  • uni-/bilateral homonymous hemianopia

• signs of brachial insufficiency (3 10%):

  • intermittent/constant pain in affected arm precipitated by increased activity of that arm

  • paresthesia, weakness, coolness, numbness, burning in fingers + hand

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  • fingertip necrosis

Location:

L:R = 3:1

Color Doppler:

• reversal of vertebral artery flow, augmented by reactive hyperemia (blood pressure cuff inflated above systolic pressure for 5 minutes)/arm exercise

Angio:

• subclavian stenosis/occlusion (aortic arch injection)

• reversal of vertebral artery flow (selective injection of contralateral subclavian/vertebral artery)

  CAVE:

  false steal = transient retrograde flow in contralateral vertebral artery caused by high-pressure injection

Rx:

bypass surgery, PTA (good long-term results)

Partial Subclavian Steal Syndrome

• = retrograde flow in systole + antegrade flow in diastole

Occult Subclavian Steal Syndrome

• = reverse flow seen only after provocative maneuvers, ie, ipsilateral arm exercise of 5 minutes/5 minutes inflation of sphygmomanometer > systolic blood pressure levels

Superior Vena Cava Syndrome

• = obstruction of SVC with development of collateral pathways

• Etiology:

  • Malignant lesion (80 90%)

    • Bronchogenic carcinoma (>50%)

    • Lymphoma

  • Benign lesion

    • Granulomatous mediastinitis (usually histoplasmosis, sarcoidosis, TB)

    • Substernal goiter

    • Ascending aortic aneurysm

    • Pacer wires/central venous catheters (23%)

    • Constrictive pericarditis

• Collateral routes:

  • Esophageal venous plexus = downhill varices (predominantly upper 2/3)

  • Azygos + hemiazygos veins

  • Accessory hemiazygos + superior intercostal veins = aortic nipple (visualization in normal population in 5%)

  • Lateral thoracic veins + umbilical vein

  • Vertebral veins

• head and neck edema (70%)

• cutaneous enlarged venous collaterals

• headache, dizziness, syncope

• with benign etiology: slower onset + progression, both sexes, 25 40 years of age

• with malignancy: rapid progression within weeks, mostly males, 40 60 years of age

• proptosis, tearing

• dyspnea, cyanosis, chest pain

• hematemesis (11%)

• superior mediastinal widening (64%)

• encasement/compression/occlusion of SVC

• dilated cervical + superficial thoracic veins (80%)

• SVC thrombus

• NUC:

  • increased tracer uptake in quadrate lobe + posterior aspect of medial segment of left lobe (umbilical pathway toward liver when injected in upper extremity)

Syphilitic Aortitis

LUETIC AORTITIS

Incidence:	in 10 15% of untreated patients (accounts for death in 1/3)
Path:	periaortitis (via lymphatics), mesaortitis (via vasa vasorum) = primarily disease of media leading to secondary injury of intima, which predisposes the intima to premature calcific atherosclerosis
Age:	between 40 and 65 years
Site:	ascending aorta (36%), aortic arch (24%), descending aorta (5%), sinus of Valsalva (1%), pulmonary artery

• thick aortic wall (fibrous + inflammatory tissue)

• saccular (75%)/fusiform (25%) dilatation of ascending aorta

• small saccular aneurysms often protrude from fusiform aneurysm

• fine pencil-like calcifications of intima (15 20%) in ascending aorta, late in disease

Cx:	(1) stenosis of coronary ostia (intimal thickening) (2) aortic regurgitation (syphilitic valvulitis), rare
DDx:	degenerative calcification of ascending aorta (older population, no aneurysm, no aortic regurgitation)

Takayasu Arteritis

• = PULSELESS DISEASE = AORTITIS SYNDROME

  • = AORTOARTERITIS = IDIOPATHIC MEDIAL AORTOPATHY

  • = AORTIC ARCH SYNDROME

• = granulomatous inflammation of unknown pathogenesis affecting mainly elastic arteries, i.e., segments of aorta + major aortic branches + pulmonary arteries limited to persons usually <50 years of age

• the only form of aortitis that produces stenosis/occlusion of the aorta!

Etiology:	probably cell-mediated inflammation
Incidence:	2.6 new cases/million/year; 2.2% (at autopsy)
Age:	12 66 years; M:f = 1:8; especially in Orientals
Histo:	(a) Acute stage: granulomatous infiltrative process focused on elastic fibers of media of arterial wall consisting of multinucleated giant cells, lymphocytes, histiocytes, plasma cells (b) fibrotic stage (weeks to years): progressive fibrosis of vessel wall resulting in constriction from intimal proliferation/thrombotic occlusion/aneurysm formation (from extensive destruction of elastic fibers in the media); ultimately leads to fibrosis of intima + adventitia Morphologically indistinguishable from temporal arteritis!

• prepulseless/systemic phase of a few months to a year

  • = nonspecific systemic signs + symptoms of fever, night sweats, weakness, weight loss, myalgia, arthralgia

  • Mean interval of 8 years between onset of symptoms and diagnosis

• pulseless phase = signs + symptoms of ischemia of

  • limb (claudication, pulse deficit, bruits) + renovascular hypertension

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• erythrocyte sedimentation rate (eSR) >20 mm/hour in 80%

Location:

Type I:	classic pulseless type = brachiocephalic trunk + carotid arteries + subclavian arteries
Type II:	combination of type I + III
Type III:	atypical coarctation type = thoracic and abdominal aorta distal to arch + its major branches
Type IV:	dilated type = extensive dilatation of the length of the aorta + its branches

• Commonly involved: left subclavian artery (<50%), left common carotid artery (20%), brachiocephalic trunk, renal arteries, celiac trunk, superior mesenteric artery, pulmonary arteries (>50%)

• Infrequently involved: axillary, brachial, vertebral, iliac arteries (usually bilaterally), coronary arteries

Angiography:

• difficult catheterization/risk of ischemic complications (increase in coagulation)

• arterial wall thickening + contrast enhancement

• full-thickness calcification (chronic disease)

• mural thrombi

CXR:

• widened supracardiac shadow >3.0 cm

• wavy/scalloped appearance of lateral margin of descending aorta

• aortic calcification (15%) commonly in aortic arch + descending aorta

• focal decrease of pulmonary vascularity

• @ Aorta

  • long + diffuse/short + segmental irregular stenosis/occlusion of major branches of aorta near their origins

  • stenotic lesions of descending thoracic aorta > abdominal aorta

  • frequent skipped lesions

  • abundant collateralization (late phase)

  • aneurysmal dilatation of ascending aorta + arch

    • = diffusely dilated lumen with irregular contours

  • fusiform/saccular aortic aneurysms (10 15%) (common in descending thoracic + abdominal aorta)

• @ Brachiocephalic arteries

  • multisegmented dilatation of carotid artery producing segmental septa

  • diffuse homogeneous circumferential thickening of vessel wall in proximal common carotid artery

  • increase in flow velocity + turbulence

  • distal CCA, ICA, ECA spared with dampened waveforms

• @ Pulmonary arteries (50 80%)

  Location:

  segmental + subsegmental (common);
  lobar + main pulmonary arteries (uncommon)

  • often late manifestation of disease

  • dilatation of pulmonary trunk (19%)

  • nodular thrombi (3%)

  • pruned tree appearance of pulmonary arteries (66%)

  • systemic-pulmonary artery shunts

  • CT angio:

    • wall thickening with enhancement (acute)

    • luminal + mural calcium deposition (chronic)

    • pulmonary artery stenosis/occlusion (chronic)

  Cx:	(1) Cerebrovascular accidents (2) Heart failure due to aortic regurgitation
  DDx:	atherosclerosis, temporal arteritis (CCA not involved), fibromuscular dysplasia (in ICA not CCA), idiopathic carotid dissection (ICA), syphilitic aortitis (calcification of ascending aorta)
  Rx:	steroids, angioplasty after decline of active inflammation

Temporal Arteritis

• = CRANIAL/GRANULOMATOUS ARTERITIS

• = POLYMYALGIA RHEUMATICA = GIANT CELL ARTERITIS (poor choice because Takayasu disease is also a giant cell arteritis)

• = systemic granulomatous vasculitis limited to persons usually >50 years of age

Incidence:

1.7 new cases/million/year

Histo:

• acute stage: granulomatous infiltrative process focused on elastic fibers of arterial wall consisting of multinucleated giant cells, lymphocytes, histiocytes, plasma cells

• fibrotic stage (weeks to years): progressive fibrosis of vessel wall resulting in constriction from intimal proliferation/thrombotic occlusion/aneurysm formation

• Morphologically indistinguishable from Takayasu arteritis!

Age peak:

65 75 years; M:F = 1:3

• prodromal phase of flulike illness of 1 3 weeks:

  • malaise, low-grade fever, weight loss, myalgia

  • unilateral headache (50 90%)

• chronic stage:

  • jaw claudication (while chewing + talking)

  • palpable tender temporal artery

  • neuroophthalmic manifestations: visual impairment /diplopia/blindness

  • polymyalgia rheumatica (50%) = intense myalgia of shoulder + hip girdles

• erythrocyte sedimentation rate (ESR) of 40 140 mm/ hour (HALLMARK)

Location:

any artery of the body; mainly medium-sized branches of aortic arch (10%), external carotid artery branches (particularly temporal artery); extracranial arteries below neck (9%): subclavian > axillary > brachial > profunda femoris > forearm > calf; commonly bilateral + symmetric

• long smooth stenotic arterial segments with skip areas

• smooth tapered occlusions with abundance of collateral supply

• absence of atherosclerotic changes

• aortic root dilatation + aortic valve insufficiency

Dx:	biopsy of palpable temporal artery
Prognosis:	disease may be self-limiting (1 2 years); 10% mortality within 2 3 years

Tetralogy Of Fallot

underdevelopment of pulmonary infundibulum secondary to unequal partitioning of the conotruncus

Frequency:

8% of all CHD; most common CHD with cyanosis after 1 year of life

TETRAD:

• Obstruction of right ventricular outflow tract: usually of pulmonary infundibulum, occasionally of pulmonic valve

• Large VSD immediately below aortic valve

• Right ventricular hypertrophy secondary to elevated RV systolic pressure

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• Overriding aorta straddling the VSD and receiving blood from both ventricles

Embryology:

• abnormal spiraling caudad growth of truncoconal ridges in 3rd 4th week causing unequal partitioning of the conotruncus into a small underdeveloped anteromedial pulmonary infundibulum + large posterolateral LV outflow tract

Hemodynamics:

fetus:	pulmonary blood flow supplied by retrograde flow through ductus arteriosus with absence of RV hypertrophy/IUGR
neonate:	R-to-L shunt bypassing pulmonary circulation with decrease in systemic oxygen saturation (cyanosis); pressure overload + hypertrophy of RV secondary to pulmonic-infundibular stenosis

Associated with:

• Bicuspid pulmonic valve (40%)

• Stenosis of left pulmonary artery (40%)

• Right aortic arch (25%)

• TE fistula

• Down syndrome

• Forked ribs, scoliosis

• Anomalies of coronary arteries in 10% (single RCA/LAD from RCA)

• cyanosis by 3 4 months of age (concealed at birth by PDA)

• dyspnea on exertion, clubbing of fingers and toes

• squatting position when fatigued (increases pulmonary blood flow)

• episodic spells = loss of consciousness

• polycythemia, lowered PO₂ values, systolic murmur in pulmonic area

• coeur en sabot (boot-shaped heart) = enlargement of right ventricle

• pronounced concavity in region of pulmonary artery trunk (small/absent PA)

• marked reduction in caliber + number of pulmonary vessels:

  • asymmetric pulmonary vascularity

  • reticular pattern with horizontal course usually in periphery (= prominent collateral circulation of bronchial vessels + pleuropulmonary connections)

• enlarged aorta

• right-sided aortic arch in 25%

OB-US:

• dilated aorta overriding the interventricular septum

• usually perimembranous VSD

• mildly stenotic RV outflow tract

• NO RV hypertrophy in midtrimester

ECHO:

• discontinuity between anterior aortic wall + interventricular septum (= overriding of the aorta)

• small left atrium

• RV hypertrophy with small right ventricular outflow tract

• widening of the aorta

• thickening of right ventricular wall + interventricular septum

Prognosis:

spontaneous survival without surgical correction in 50% up to age 7; in 10% up to age 21

Rx: surgery in early childhood

• palliative

  • Blalock-Taussig shunt = end-to-side anastomosis of subclavian to pulmonary artery opposite aortic arch (64% survival rate at 15 years, 55% at 20 years)

  • Pott operation on left = anastomosis of left PA with descending aorta

  • Waterston-Cooley procedure = anastomosis between ascending aorta + right pulmonary artery

  • Central shunt = Rastelli procedure = tubular synthetic graft between ascending aorta + pulmonary artery

• corrective open cardiac surgery = VSD-closure + reconstruction of RV outflow tract by excision of obstructing tissue (82% survival rate at 15 years)

Operative mortality:

3 10%

Pink Tetralogy

• = infundibular hypertrophy in VSD (3%)

Pentalogy of Fallot

• = tetralogy + ASD

Trilogy of Fallot (infantile presentation)

• Severe pulmonic valvular stenosis

• Hypertrophy of RV

• ASD with R-to-L shunt (increased pressure in RA forces foramen ovale open)

Thoracic Outlet Syndrome

• = compression of nerves, veins, and arteries between chest and arm

Cause:

• CONGENITAL

  • Cervical rib

  • Scalenus minimus muscle (rare) extending from transverse process of 7th cervical vertebra to 1st rib with insertion between brachial plexus + subclavian artery

  • Anterior scalene muscle = scalenus anticus syndrome (most common) = wide/abnormal insertion/hypertrophy of muscle

  • Anomalous 1st rib = unusually straight course with narrowing of costoclavicular space

• ACQUIRED

  • Muscular body habitus

    • = arterial compression in pectoralis minor tunnel

  • Slender body habitus

    • with long neck, sagging shoulders

  • Fracture of clavicle/1st rib (34%)

    • with nonanatomic alignment/exuberant callus

  • Supraclavicular tumor/lymphadenopathy

  • pain in forearm + hand that increases upon elevation of arm

  • paresthesias of hand + fingers (numbness, pins and needles ) in 95%

  • decreased skin temperature, discoloration of hand

  • intermittent claudication of fingers (from ischemia)

  • hyperabduction maneuver with obliteration of radial pulse (34%)

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  • Raynaud phenomenon (40%): episodic constriction of small vessels

  • supraclavicular bruit (15 30%)

Bidirectional Doppler:

• Adson maneuver (for scalenus anticus muscle) = hold deep inspiration while neck is fully extended + head turned toward ipsilateral and opposite side

• Costoclavicular maneuver (compression between clavicle + 1st rib) = exaggerated military position with shoulders drawn back and downward

• Hyperabduction maneuver (compression by humeral head/pectoralis minor muscle) = extremity monitored through range of 180 abduction

• complete cessation of flow in one position

Photoplethysmography:

• Photo pulse transducer secured to palmar surface of one fingertip of each hand

• Arterial pulsations recorded with arm in

  • neutral position

  • extended 90 to side

  • 180 over the head

  • in military position with arms at 90 + shoulders pressed back

• complete disappearance of pulse in one position

Angio:

• abnormal course of distal subclavian artery

• focal stenosis/occlusion

• poststenotic dilatation of distal subclavian artery

• aneurysm

• stress test: bandlike/concentric constriction

• mural thrombus distal embolization

• venous thrombosis/obstruction

DDx:

Cervical disk disease, radiculopathy, spinal cord tumor, trauma to brachial plexus, arthritis, carpal tunnel syndrome, Pancoast tumor, peripheral arterial occlusive disease, aneurysm, causalgia, thromboembolism, Raynaud disease, vasculitis

Transposition Of Great Arteries

Complete Transposition of Great Arteries

• = TGA = D-TRANSPOSITION

• = great vessels originate from inappropriate ventricle:

  • aorta originating from RV with an infundibulum

  • pulmonary artery originating from LV

  • normal position of atria + ventricles

Embryology:

• failure of the aorticopulmonary septum (= truncoconal ridges) to follow a spiral course

Incidence:

10% of all CHD

VARIATIONS:

• Complete TGA + intact interventricular septum

• Complete TGA + VSD: CHF due to VSD

• Complete TGA + VSD + PS: PS prevents CHF = longest survival

Hemodynamics:

fetus:	no hemodynamic compromise with normal birth weight
neonate:	mixing of the 2 independent circulations necessary for survival

Admixture of blood from both circulations via:

• PDA (carries aortic blood into pulmonary artery) + patent foramen ovale (allows saturated blood to enter RA from LA)

  Prognosis:

  worst when PDA closes

• VSD (in 50%)

• cyanosis (most common cause for cyanosis in neonate) 2nd most common cause of cyanosis after tetralogy of Fallot

• symptomatic 1 2 weeks following birth

CXR:

• egg-on-its-side appearance of heart = narrow superior mediastinum secondary to hypoplastic thymus + hyperaeration + abnormal relationship of great vessels

• cardiac enlargement beginning 2 weeks after birth

• right heart enlargement

• enlargement of LA (with VSD)

• absent pulmonary trunk (99%) = PA located posteriorly in midline

• increased pulmonary blood flow (if not associated with PS)

• midline aorta (30%)/ascending aorta with convexity to the right

• right aortic arch in 3% (difficult assessment due to midline position + small size)

OB-US:

• great arteries arise from ventricles in a parallel fashion

• aorta anterior + to right of pulmonary artery (in 60%; rarely side by side)

Prognosis:

overall 70% survival rate at 1 week, 50% at 1 month, 11% at 1 year by natural history

Variation of Transposition

Rx:

• Prostaglandin E1 administration to maintain ductal patency

• Rashkind procedure = balloon septostomy to create ASD

• Blalock-Hanlon procedure = surgical creation of ASD

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• Mustard operation (corrective) = removal of atrial septum + creation of intraatrial baffle directing the pulmonary venous return to RV + systemic venous return to LV; 79% 1-year survival rate; 64 89% 5-year survival

Corrected Transposition of Great Arteries

• = CONGENITALLY CORRECTED TRANSPOSITION = L-TRANSPOSITION = VENTRICULAR INVERSION

• = anomalous looping of the bulboventricular loop

  • (= primordial ventricles) associated with lack of spiral rotation of conotruncal septum characterized by

  • Transposition of great arteries (= aorta anterior + to right of PA)

  • Inversion of ventricles (LV on right side, RV on left side):

    • RA connected to morphologic LV

    • LA connected to morphologic RV

  • AV valves + coronary arteries follow their corresponding ventricles

Hemodynamics:

functionally corrected abnormality

Associated with:

• usually perimembranous VSD (in >50%)

• pulmonic stenosis (in 50%)

• anomaly of left (= tricuspid) atrioventricular valves (Ebstein-like) leading to insufficiency

• dextrocardia (high incidence)

• NO cyanosis

• atrioventricular block (malalignment of atrial + ventricular septa)

CXR:

• abnormal convexity/straightening in upper portion of left heart border (ascending aorta arising from inverted RV)

• inapparent aortic knob + descending aorta (overlying spine)

• inapparent pulmonary trunk (rightward posterior position) = PREMIER SIGN

• humped contour of lower left heart border with elevation above diaphragm (anatomic RV)

• apical notch (= septal notch)

• increased pulmonary blood flow (if shunt present)

• pulmonary venous hypertension (if left-sided AV valve incompetent)

• LA enlargement

MR:

• posterior cardiac chamber has moderator band + muscular infundibulum (morphologic RV)

Angio:

• original LV on right side: smooth-walled, cylinder-/cone-shaped with high recess emptying into aorta (= venous ventricle)

• original RV on left side: bulbous, triangular shape, trabeculated chamber with infundibular outflow tract into pulmonary trunk (= arterial ventricle)

OB-US:

• great arteries arise from ventricles in a parallel fashion

• aortic valve separated from tricuspid valve by a complete infundibulum

• fibrous continuity between pulmonic valve + mitral valve

Prognosis:

(unfavorable secondary to additional cardiac defects) 40% 1-year survival rate, 30% 10-year survival rate

Traumatic Aortic Injury

• = AORTIC LACERATION = BLUNT TRAUMA TO THORACIC AORTA

• = laceration that disrupts the physical integrity of >1 structural layers of the aorta

Incidence:	>100,000 people in United States/year
Cause:	rapid deceleration (high-speed MVA >48 km/h with unrestrained driver or ejected passenger, fall from height >3 m)/crushing chest injury
Pathomechanism:	horizontal/vertical deceleration, hydrostatic force, osseous pinch
Length of tear:	circumferential tear (in majority)
Site:	(a) Aortic isthmus just distal to left subclavian artery (88 95%): brachiocephalic arteries + ligamentum arteriosum fix aorta in this region
	(b) Aortic arch with avulsion of brachiocephalic trunk (4.5%)
	(c) Ascending aorta immediately above aortic valve (5 9%)
	Cx:	aortic valve rupture, coronary artery laceration, hemopericardium + cardiac tamponade; NO mediastinal hematoma
	(d) Diaphragmatic hiatus (1 3%)
	Most often posteriorly (in noncircumferential tear)

Extent of laceration:

• Incomplete rupture (15%)

  • Aorta goes on to rupture completely within 24 hours in 50% of patients!

  • INTIMA

    • (a) intimal hemorrhage without tear

    • (b) transverse laceration of intima with hemorrhage (= intimal tear/flap = traumatic aortic dissection)

    • Minimal aortic injury (10%) = intimal flap of <10 mm without significant periaortic hematoma

  • MEDIA

    • tear into media with subadventitial hematoma (40 60%)

  • ADVENTITIA

    • periaortic hemorrhage ( aortic injury)

    • traumatic pseudoaneurysm = laceration of intima + media + adventitia with locally contained periadventitial hematoma

• Complete rupture (85%) = transmural extension of laceration = aortic transection = traumatic aortic rupture

  • exsanguination before reaching a hospital

Acute Thoracic Aortic Injury

Prevalence:

10 16 20% of all fatalities in high-speed deceleration accidents

• severe chest pain: precordial (ascending aorta), neck-jaw (aortic arch), interscapular (descending thoracic aorta)

• anterior chest wall contusion, dyspnea, dysphagia

• blood pressure changes:

  • unexplained hypotension

  P.660

  
  

  • scapulothoracic syndrome = decreased/absent upper extremity pulses

  • acute coarctation syndrome = decreased/absent lower extremity + normal upper extremity pulses with upper extremity hypertension + systolic murmur in 2nd left parasternal interspace

CXR (53 100% sensitive, 1 60% specific, 4 20% PPV):

• A normal anteroposterior upright CXR virtually excludes acute thoracic aortic injury (96 98% negative predictive value)!

N.B.:

There are no plain CXR findings of aortic injury (since aortic integrity is maintained by intact adventitia)! The sources of mediastinal hematoma are frequently the azygos, hemiazygos, internal thoracic, paraspinal and intercostal vessels!
Aortic injury is the cause of mediastinal hematoma in only 12.5%!

• normal admission CXR in 28% (radiographic signs may not develop until 6 36 hours): supine CXR is very inaccurate for mediastinal widening

• Most specific signs:

  • deviation of nasogastric/endotracheal tube to the right of T3-T4 spinous process (12 100% sensitive, 80 95% specific)

  • depression of left mainstem bronchus anteroinferiorly >40 below the horizontal + toward right (53%)

• mediastinal widening >8 cm at level of origin of left subclavian artery (present in 75 92%; 53 93 100% sensitive, 1 34 60% specific):

  • mediastinal width to chest width >0.25

• indistinct aortic contour at arch/descending aorta (53 100% sensitive, 21 55% specific)

• obscuration of aortopulmonary window (40 100% sensitive, 56 83% specific)

• widened left paraspinal stripe >5 mm (12 83% sensitive, 89 97% specific)

• thickening of right paratracheal stripe >4 5 mm

  • (= hematoma between pleura + trachea)

• left/right apical pleural cap sign in 37%

  • (= extrapleural hematoma along brachiocephalic vessels)

• tracheal compression + displacement toward right (61%)

• rapidly accumulating commonly left-sided hemothorax without evident rib fracture (break in mediastinal pleura)

• fractures of 1st + 2nd rib (17%)

mnemonic:

BAD MEAT

• Bronchus depression (left main)

• Aortic silhouette shaggy

• Death in 80 90%

• Mediastinal widening

• Enteric (nasogastric) tube displacement

• Apical cap

• Tracheal shift

NECT screening (90 100% sensitive, 19 45% specific, 0 50% PPV, 94 100% NPV):

• obliteration of aorta-fat interface with increased attenuation (= mediastinal/periaortic hematoma)

• A negative CT examination for mediastinal hemorrhage has an almost 100% NPV for aortic injury!

• All patients with periaortic/middle/superior mediastinal hemorrhage require aortography! Save your contrast for that study!

• If hematomas are seen only in anterior/posterior mediastinum traumatic aortic injury is very unlikely!

• False positive:

  • residual thymic tissue, periaortic atelectasis, pericardial recess, patient motion, streak artifacts, volume averaging of pulmonary artery, pleural effusion adjacent to descending aorta, sternal + spinal fracture

CECT (100% sensitive; 92 99% specific; 0 39% false positive; 0.7% false negative):

Technique:

100 150 mL at 2 mL/sec with 20 30 second scanning delay
Helical multislice CT has become a major screening tool!

Advantages:

• negative findings will obviate invasive angio

• unsuspected injuries are discovered (pulmonary contusion, pneumothorax, pericardial effusion, rib fracture)

Disadvantages:

• CT delays the definitive aortography + surgery

• few data exist on accuracy of CT for branch vessel injury

• intraluminal low-density filling defect:

  • linear = intimal flap

  • polypoid = clot

• contour deformity of outer aortic wall = pseudoaneurysm

• contour deformity of inner aortic wall:

  • intramural hematoma

  • pseudocoarctation = abrupt tapering of the diameter of the descending aorta compared with the ascending aorta

• extravasation of contrast material (rare)

• False positive:

  • pulsation artifact (aortic valve leaflets, wall of ascending aorta, cardiac motion), streak artifact from high-density contrast in brachiocephalic vein, volume averaging, prominent periaortic bronchial/mediastinal vessels, atherosclerotic pseudoaneurysm, small ductus diverticulum

• Transesophageal echocardiography:

  • (in 2 15% technically unsuccessful, 57 63% sensitive, 84 91% specific):

  • intimal flap

  • intraluminal thick stripes

  • pseudoaneurysm

  • aortic occlusion (= pseudocoarctation)

  • fusiform aneurysm

  • aortic wall hematoma

• Aortography (92% sensitive, 98 100% specific):

Technique:	LAO + RAO projection; high-flow pigtail catheter; 50 mL at 35 mL/sec
Morbidity:	1.7% (iatrogenic extension of flap, entry of guidewire into pseudoaneurysm)
Delay:	147 minutes between admission and angio

True positive:

• in 17 20% of patients with mediastinal hematoma angio demonstrates acute traumatic aortic injury!

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False negative:

• small transverse intimal tears may be missed!

• resistance in advancing guide wire

• intimal irregularity, linear defect, filling defect = intimal flap = posttraumatic dissection (5 10%)

• intramural injury:

  • thickening of aortic wall

  • posttraumatic coarctation

• transmural laceration:

  • contained extravasation = traumatic false aneurysm

  • free extravasation = aortic rupture

DDx:

ductus diverticulum (in 10% of normals), aortic spindle, infundibula of brachiocephalic arterial branches; volume averaging with left brachio-cephalic vein/left superior intercostal vein/right bronchial arteries (vs. intimal flap); artifact from physiologic streaming/mixing of contrast material; atherosclerotic aortic ulceration; atheromatous plaque; syphilitic aortic aneurysm

Recommendations for work-up:

• Normal well-defined mediastinal contours on CXR: no further imaging

• Unstable patient + unequivocally abnormal CXR/strong clinical evidence of aortic injury: angiography/emergency surgery

• Stable patient

  • with unequivocally abnormal CXR:

    • CT of chest + head + abdomen (while waiting for angiographic examination)

  • with equivocal CXR: screening CT of chest

  • abnormal chest CT:

    • angiography for confirmation/surgery

Rx:

(1) Antihypertensive medication
(2) Surgical repair (20 54% mortality, 5 10% morbidity from paraplegia)

Prognosis:

• 80 90% fatal at scene of accident

• 10 20% reach hospital (due to formation of periaortic hematoma + false aneurysm contained by adventitia surrounding connective tissue)

  • without intervention: 30% dead within 6 hours; 40 50% dead within 24 hours, 90% dead within 4 months; chronic false aneurysm may develop in 2 5% at isthmus/descending aorta

  • with surgical repair: 60 70% survive; surgical mortality rate of 9 44% varies with degree of hemodynamic instability + severity of associated injuries + magnitude of aortic laceration

Cx:

postoperative paraplegia (9%) due to aortic cross clamping >30 minutes

Chronic Posttraumatic Aortic Pseudoaneurysm

• = aneurysm existing for >3 months (amount of wall fibroplasia following rupture usually not sufficient to prevent subsequent rupture until at least 3 months after initial traumatic episode)

Incidence:

2 5% of patients surviving aortic transection >24 48 hours

• symptom-free period of months to years (in 11% >10 years)

• delayed clinical symptoms (42% within 5 years, 85% within 20 years): chest pain, back pain, dyspnea, cough, hoarseness, dysphagia, systolic murmur

Location:

descending aorta at level of lig. arteriosum filling the aorticopulmonary window (most commonly)

• well-defined rounded mass in left paramediastinal region

• inferior displacement of left mainstem bronchus

Cx:	CHF, partial obstruction of aortic lumen, bacterial endocarditis, aortoesophageal fistula, aortic dissection, obstruction of tracheobronchial tree, systemic emboli
Prognosis:	enlargement + eventual rupture;
10-year survival rate:	85% with surgical repair, 66% without surgical repair

Tricuspid Atresia

2nd most common cause of pronounced neonatal cyanosis (after transposition) characterized by

• absent tricuspid valve

• ASD

• small VSD (in most patients)

Frequency:	1.5% of all CHD
Embryology:	imbalanced tissue proliferation + resorption results in absence of valvular tissue

• TRICUSPID ATRESIA WITHOUT TRANSPOSITION (80%)

  • without PS, (b) with PS, (c) with pulmonary atresia

• TRICUSPID ATRESIA WITH TRANSPOSITION

  • without PS, (b) with PS [most favorable combination], (c) with pulmonary atresia

• Usually small VSD + PS (75%) restrict pulmonary blood flow

Hemodynamics:

• absent tricuspid valve forces blood from an enlarged RA through an ASD into LA (R-to-L shunt); pulmonary blood flow limited by pulmonary valvular stenosis

• progressive cyanosis from birth on, increasing with crying = OUTSTANDING FEATURE (inverse relationship between degree of cyanosis + volume of pulmonary blood flow)

• pansystolic murmur (VSD)

• ECG: left-axis deviation

CXR (typical cardiac contour):

• heart size ranging from normal to moderately enlarged (depending on volume of pulmonary blood flow and size of RA)

• left rounded contour = enlargement + hypertrophy of LV

• right rounded contour = enlarged RA

• flat/concave pulmonary segment

• normal/decreased pulmonary vascularity

• typical flattening of right heart border with transposition (in 15%)

Prognosis:

may survive well into early adulthood

Rx:

• Blalock-Taussig procedure (if pulmonary blood flow decreased in infancy)

• Glenn procedure = shunt between IVC + right PA (if total correction not anticipated)

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• Fontan procedure = external conduit from RA to pulmonary trunk + closure of ASD (if pulmonary vascular disease has not developed)

Tricuspid Insufficiency

Cause:

• Right ventricular failure (most common)

• Carcinoid syndrome

• Bacterial endocarditis

• Rheumatic heart disease

• Congenital heart disease: Ebstein anomaly, atrioventricular cushion defect

• normal/reduced pulmonary vascularity

• cardiomegaly

• RA + RV enlargement

• distension of IVC > SVC

Trousseau Syndrome

PARANEOPLASTIC THROMBOEMBOLISM

Incidence:	1 11%; higher in terminally ill cancer patients
Tumors:	mucin-secreting adenocarcinoma of GI tract and pancreas (most common), lung, breast, ovary, prostate
Pathogenesis:	(?) (a) tumors activate coagulation + depress anticoagulant function (b) cancer cells cause injury to endothelial lining, activate platelets + coagulation
Type of lesion:	(1) Venous thrombosis (2) Arterial thromboembolism (3) Nonbacterial thrombotic endocarditis

• Patients with thromboembolism have an increased incidence of occult malignancy!

Prevalent criteria:

• absence of apparent cause for thromboembolism

• age >50 years

• multiple sites of venous thrombosis

• simultaneous venous + arterial thromboembolism

• resistance to oral anticoagulant therapy

• associated other paraneoplastic syndromes

• regression of thromboembolism with successful treatment of cancer

• disorders of consciousness (cerebral emboli)

• muscular pain + weakness (emboli to skeletal muscle)

• decompensated disseminated intravascular coagulation

• deep vein thrombosis

• pulmonary embolism

• nonbacterial thrombotic endocarditis (echocardiography)

Rx:

(1) Heparin (more successful than warfarin)
(2) Greenfield filter

Truncus Arteriosus

• = PERSISTENT TRUNCUS ARTERIOSUS = SINGLE OUTLET OF THE HEART

• = failure of septation of the conotruncus characterized by

  • one great artery arising from the heart giving rise to the coronary, pulmonary, and systemic arteries, and straddling a

  • large VSD

Incidence:

2% of all CHD

Types:

Type I (50%)	= main PA + aorta arise from common truncal valve
Type II (25%)	= both pulmonary arteries arise from back of trunk
Type III (10%)	= both pulmonary arteries arise from side of trunk
Type IV	= pseudotruncus = absence of pulmonary arteries; pulmonary supply from systemic collaterals arising from descending aorta
Subtype A	= infundibular VSD present
Subtype B	= VSD absent

Associated with:

• Right aortic arch (in 35%)

  • right aortic arch + cyanosis + shunt vascularity = TRUNCUS

• Forked ribs

Hemodynamics:

• admixture lesion (R-to-L and L-to-R shunt across VSD) with volume of pulmonary blood flow inversely related to degree of pulmonary vascular resistance

fetus:	CHF only with incompetent valve secondary to massive regurgitation from truncus to ventricles
neonate:	L-to-R shunt after decrease in pulmonary resistance (massive diversion of flow to pulmonary district) leads to CHF (ventricular overload)/pulmonary hypertension with time

Variation In Truncus Arteriosus

P.663

• moderate cyanosis (degree inversely related to volume of pulmonary blood flow), apparent with crying

• severe CHF within first days/months of life (in large R-to-L shunt)

• systolic murmur (similar to VSD)

• early diastolic murmur (with truncal insufficiency)

• wide pulse pressure

CXR:

• cardiomegaly:

  • increased volume of both ventricles

  • enlarged LA (50%) secondary to increased pulmonary blood flow

• wide mediastinum due to large aortic shadow = truncus arteriosus

• waterfall/hilar comma sign = elevated right hilum (30%); elevated left hilum (10%)

• concave pulmonary segment (50%) (type I has left convex pulmonary segment)

• markedly increased pulmonary blood flow, may be asymmetric

ECHO:

• single arterial vessel overriding the interventricular septum (DDx: tetralogy of Fallot)

• frequently dysplastic single semilunar valve with 3 6 leaflets (most commonly 3 leaflets)

  • truncal valve may be stenotic

  • truncal valve insufficiency with age (in 25%)

Prognosis:	40% 6-months survival rate, 20% 1-year survival rate
Rx:	Rastelli procedure (30% no longer operable at 4 years of age) = (a) artificial valve placed high in RVOT and attached via a Dacron graft to main pulmonary artery (b) closure of VSD

Hemitruncus

• = rare anomaly characterized by

  • one pulmonary artery (commonly right PA) arising from trunk

  • one pulmonary artery arising from RV/supplied by systemic collaterals

Associated with:

PDA (80%), VSD, tetralogy (usually isolated to left PA)

• acyanotic

Pseudotruncus Arteriosus

• = TRUNCUS TYPE IV

• = severe form of tetralogy of Fallot with atresia of the pulmonary trunk; entire pulmonary circulation through bronchial collateral arteries (NOT a form of truncus arteriosus in its true sense); characterized by

  • pulmonary atresia

  • VSD with R-to-L shunt

  • RV hypertrophy

Associated with:

right aortic arch in 50%

• cyanosis

• concavity in area of pulmonary segment

• commalike abnormal appearance of pulmonary artery

• absent normal right and left pulmonary artery (lateral chest film)

• esophageal indentation posteriorly (due to large systemic collaterals)

• prominent hilar + intrapulmonary vessels (= systemic collaterals)

• coeur en sabot = RV enlargement

• prominent ascending aorta with hyperpulsations

Ventricular Aneurysm

• CONGENITAL LEFT VENTRICULAR ANEURYSM

  • rare, young Black adult

  • Submitral type:

    • bulge at left middle/upper cardiac border

  • Subaortic type:

    • small + not visualized

    • heart greatly enlarged (from aortic insufficiency)

• ACQUIRED LEFT VENTRICULAR ANEURYSM

  • = complication of myocardial infarction, Chagas disease

  • may be asymptomatic + well tolerated for years

  • occasionally associated with persistent heart failure, arrhythmia, peripheral embolization

True Ventricular Aneurysm

• = circumscribed noncontractile outpouching of ventricular cavity with broad mouth + localized dyskinesis

Cause:

sequelae of transmural myocardial infarction

Location:

• left anterior + anteroapical: readily detected (anterior + LAO views)

• inferior + inferoposterior: less readily detected (steep LAO + LPO views)

Detection rate:

50% by fluoroscopy; 96% by radionuclide ventriculography; frequently not visible on CXR

• localized bulge of heart contour = squared-off appearance of mid left lateral margin of heart border

• localized paradoxical expansion during systole (CHARACTERISTIC)

• rim of calcium in fibrotic wall (chronic), rare

• akinetic/severely hypokinetic segment

• left ventriculography in LAO, RAO is diagnostic

• wide communication with heart chamber (no neck)

Cx:	wall thrombus with embolization
Prognosis:	rarely ruptures

Pseudoaneurysm of Ventricle

• = FALSE ANEURYSM

• = left ventricular rupture contained by fused layers of visceral + parietal pericardium/extracardiac tissue

  • cardiac rupture with localized hematoma contained by adherent pericardium; typically in the presence of pericarditis

  • subacute rupture with gradual/episodic bleeding

Etiology:	trauma, myocardial infarction
Location:	typically at posterolateral/diaphragmatic wall of LV

• left retrocardiac double density

• diameter of mouth smaller than the largest diameter of the globular aneurysm

• delayed filling

P.664

Cx:

high risk of delayed rupture (infrequent in true aneurysms)

Ventricular Septal Defect

• Most common CHD (25 30%):

  • isolated in 20%

  • with other cardiac anomalies in 5% (PDA, CoA)

• Acyanotic L-to-R shunt + right aortic arch (in 2 5%) = VSD

Embryology:

• single ventricular chamber divides into two by fusion of membranous portion of ventricular septum + endocardial cushions + bulbis cordis (= proximal part of truncus arteriosus) between 4 8th week

• MEMBRANOUS = PERIMEMBRANOUS VSD (75 80%)

  Location:

  posterior + inferior to crista supraventricularis near commissure between right and posterior (= noncoronary) aortic valve cusps

  • May be associated with:

    • small aneurysms of membranous septum commonly leading to decrease in size of membranous VSD (their presence does not necessarily predict eventual complete closure)

• SUPRACRISTAL = CONAL VSD (5 8%)

  • Crista supraventricularis = inverted U-shaped muscular ridge posterior + inferior to pulmonary valve

  • RV view = VSD just beneath pulmonary valve with valve forming part of superior margin of defect

  • LV view = VSD just below commissure between R + L aortic valve cusps

  Cx:

  right aortic valve cusp may herniate into VSD (= aortic insufficiency)

• MUSCULAR VSD (5 10%)

  • May consist of multiple VSDs; bordered entirely by myocardium

  Location:

  (a) inlet portion
  (b) trabecular portion
  (c) infundibular/outlet portion

• ATRIOVENTRICULAR CANAL TYPE

  • = ENDOCARDIAL CUSHION TYPE = POSTERIOR VSD (5 10%)

  Location:

  adjacent to septal + anterior leaflet of mitral valve; rare as isolated defect

• Hemodynamics:

  • small bidirectional shunt during fetal life (similar pressures in RV + LV); after birth pulmonary arterial pressure decreases + systemic arterial pressure increases with development of L-to-R shunt

• Classification:

  • Maladie de Roger

    • = small restrictive VSD with defect <1 cm; little/no hemodynamic significance with normal pulmonary artery pressure, normal pulmonary vascular resistance

    • asymptomatic

    • holosystolic heart murmur at 4th left rib interspace

    • normal plain film

    Prognosis:

    spontaneous closure

  • Moderate Shunt

    • VSD defect <75% of aortic diameter (1 1.5 cm); systolic LV pressure > systolic RV pressure; intermediate pulmonary artery pressure; normal pulmonary vascular resistance

      

    • respiratory infections, mild dyspnea

    • slight prominence of pulmonary vessels (45% shunt)

    • slight enlargement of LA

    Prognosis:

    spontaneous closure in large percentage

  • Nonrestrictive Large Shunt

    • VSD defect >75% of aortic diameter; systolic LV pressure = systolic RV pressure (pulmonary vascular disease + hypertension increases RV pressure); pulmonary artery pressure approaching systemic levels; slightly increased pulmonary vascular resistance; pulmonary blood flow 2 4 systemic flow;

      

    • bouts of respiratory infections

    • feeding problems, failure to thrive

    • CHF soon after birth (due to RV overload)

    • prominent pulmonary segment + vessels (= shunt vascularity)

    • calcification of pulmonary arteries

      • = PATHOGNOMONIC for pulmonary arterial hypertension

    • enlargement of LA + LV

    • normal/small thoracic aorta

  • Eisenmenger syndrome

    • large VSD eventually leads to shunt reversal (R-to-L shunt) due to irreversible increase in pulmonary vascular resistance (= intima + medial hyperplasia) when pulmonary vascular resistance >0.75 of systemic vascular resistance

      

      Frequency:

      10% of large VSDs by 2 years of age

    • cyanotic, but less symptomatic; CHF rare

    • eventual decrease of pulmonary vessel caliber

    • eventual decrease in size of LA + LV

NATURAL HISTORY OF VSD causing reduction in pulmonary blood flow:

• Spontaneous closure

  • in 40% within first 2 years of life; 60% by 5 years (65% with muscular VSD, 25% with membranous VSD); with large VSD in 10%; with small VSD in 50%

• RVOT obstruction

  • infundibular hypertrophy in 3% = pink tetrad

• Prolapse of right aortic valve cusp

  • = aortic valve insufficiency

CXR (with increase in size of VSD):

• variable appearance due to variations in defect size

• enlargement of LA

• enlargement of pulmonary artery segment

• enlargement of LV

• RV hypertrophy

• increase in pulmonary blood flow (if >45% of pulmonary blood flow from systemic circulation)

• Eisenmenger reaction

ECHO:

• prolapse of aortic valve cusp (in supracristal VSD)

• deformity of aortic cusp (in membranous VSD)

P.665




• lack of echoes in region of interventricular septum with sharp edges (DDx: artifactual dropout with sound beam parallel to septum); muscular VSD difficult to see

• LA enlargement

Angio:

• Projections:

  • LAO 60 C-C 20 for membranous + anterior muscular VSD

  • LAO 45 C-C 45 (hepatoclavicular) for posterior endocardial cushion + posterior muscular VSD

  • RAO for supracristal VSD + assessment of RVOT

  • RVOT/pulmonary valve fill without filling of RV chamber (in supracristal VSD)

• Rx:

  • large VSD + left heart failure at 3 months of age: aim is to delay closure until child is 18 months of age; pulmonary-to-systemic blood flow >2:1 requires surgery before pulmonary hypertension becomes manifest

    • Digitalis + diuretics

    • Pulmonary artery banding

    • Patching of VSD: surgical approach through RA/through RV for supracristal VSD

  • small VSDs without increase in pulmonary arterial pressure are followed