Congenital Heart Disease

Congenital Heart Disease Acyanotic: With shunt: e.g. ASD, VSD, PDA Without shunt: e.g. PS, coarctation of the aorta, congenital AS, congenital MS…… Cyanotic With reduced pulmonary blood flow: e.g. TOF With increased blood flow: TGA

Common Congenital Heart Disease Atrial septal defect (ASD) Osteum secundum Osteum primum Ventricular septal defect (VSD) Patent ductus arteriosus (PDA) Coarctation of the aorta Congenital pulmonary stenosis Tetralogy of Fallot (TOF)

Clinical Presentation of CHD Asymptomatic Congestive heart failure Cyanosis and digital clubbing Failure to thrive Recurrent chest infections

Clinical Presentation of CHD Heart murmur Pulmonary hypertension with reversed shunt (Eisenmenger syndrome)

Pulmonary Hypertension Initially caused by increased blood flow through the pulmonary vessels due to left-to-right shunt

Pulmonary Hypertension Later on: structural changes affect the walls of pulmonary arterioles, including: Arterial wall thickening intraluminal thrombosis Capillary obliteration

Pulmonary Hypertension This leads to: increased resistance to pulmonary blood flow Reduction of pulmonary blood flow Right-to-left shunt through the connection between the two circulations (reversed shunt, the Eisenmenger’s syndrome)

Eisenmenger’s Syndrome: clinical features Cyanosis and clubbing Raised JVP Left parasternal heave (RVH) Systolic expansion of the pulmonary artery Palpable second heart sound Loud pulmonary second sound

Eisenmenger’s Syndrome: clinical features RV third heart sound Murmurs: early diastolic murmur at the pulmonary area (Graham-Steel murmur) Tricuspid regurgitation (pansystolic murmur at LSB)

Eisenmenger’s Syndrome: clinical features ECG: Right axis deviation Right ventricular hypertrophy (tall R waves in V1& V2) Peaked P wave (RA enlargement) CXR shows enlarged central pulmonary arteries & peripheral pruning of the pulmonary arteries

Complications of Cyanotic Heart Disease Polycythemia: hyperviscosity syndrome Hemoptysis, sometimes massive and fatal Paradoxical embolization Brain abscess

Atrial Septal Defect (ASD) Osteum primum ASD: part of endocardial cushion defects associated with mitral regurgitation and tricuspid regurgitation Osteum secundum ASD: at the area of fossa ovalis

ASD: Pathophysiology Shunting of blood from LA to RA through the defect leads to dilatation of RA, RV, & PA, but not LA or LV

ASD: Pathophysiology The magnitude of the shunt depends on the difference in compliance of the RV & LV. The size of the defect has a minor significance (≠VSD)

ASD: Symptoms Dyspnea Recurrent chest infections Heart failure Arrhythmias (palpitations)

ASD: Signs ↑ JVP Left parasternal heave Fixed splitting of S2 Systolic murmur at the pulmonary area NO THRILL is felt at the pulmonary area (unlike valvular PS)

ASD: Investigations ECG: CXR Echocardiography Trans-esophageal echocardiography (TEE)

ASD: ECG Incomplete RBBB With secundum ASD: right axis deviation With primum ASD: left axis deviation

ASD: CXR Dilated RV, RA, and PA plethoric lungs: increased pulmonary arterial and venous markings

Echocardiography & TEE Shows the size of the defect The direction of blood flow The pulmonary artery pressure

ASD: Management Surgical closure when the shunt is large (exceeds 1.5:1) Recently: closure with implantable closure devices during cardiac catheterization Endocarditis prophylaxis for primum ASD

ASD: Management Endocarditis prophylaxis is not required in osteum secundum ASD unless associated with other valvular or congenital defects

Ventricular Septal Defect (VSD) Failure of septation of the ventricles The interventricular septum is normally composed of small membranous and large muscular parts.

Ventricular Septal Defect (VSD) The usual position of the defect is around the membranous septum (perimembranous VSD)

VSD: Pathophysiology The magnitude of the shunt depends on the size of the defect & the relative systemic & pulmonary resistance

VSD: Pathophysiology The shunt involves the LV, RV, PA, PVs, & LA

VSD: Pathophysiology The shunt does not involve the RA or the aorta There is increased flow through the mitral valve & LV volume overload

VSD: Clinical Presentation Dyspnea Recurrent chest infections Heart failure Accidental finding of a murmur Eisenmenger’s syndrome

VSD: Physical Findings Hyperdynamic apex beat Systolic thrill: flow through the defect Physiological splitting of S2 (↑ with breathing) S3: LV volume overload

VSD: Physical Findings LV-RV shunt causes pansystolic murmur at the left sternal border Increased flow through the mitral valve causes diastolic murmur at the apex

VSD: Investigations ECG CXR Echocardiography

VSD: CXR Plethoric lungs Prominent main pulmonary artery LA dilatation The heart size may be enlarged

VSD: ECG LVH: Tall R waves in V5 & V6 Deep S waves in V1 & V2

VSD: Echocardiography

VSD: Treatment Small defects: no indication for surgical closure Attention should be paid for endocarditis prophylaxis

VSD: Treatment Large defects with heart failure: Medical treatment: digoxin, diuretics, ACEIs Definitive treatment: surgical repair of the defect Lately: closure by catheterization (occluder)

VSD: Treatment If the Eisenmenger’s syndrome has developed: Heart-lung transplantation

Patent Ductus Arteriosus Normally, the ductus arteriosus closes before the 4th week of life Failure of closure of the ductus is more common in females

PDA: Pathophysiology Pressure gradient between the aorta & PA occurs throughout the cardiac cycle This leads to continuous flow of blood from the aorta to PA

PDA: Pathophysiology The shunt involves PA, LA, LV, & aorta The RV and RA are not involved in the shunt

PDA: Pathophysiology The magnitude of the shunt depends on the size of the communication Usually there is LV volume overload and increased flow through the mitral valve

PDA: Clinical Presentation Exertional dyspnea Recurrent chest infections Congestive heart failure

PDA: Clinical Presentation Eisenmenger syndrome with differential cyanosis: Cyanosis of the toes but not the fingers The right to left shunt bypasses the cerebral and upper limb vessels & flows directly into the aorta

PDA: Physical Findings Large volume pulse Left ventricular dilatation (displaced apex beat) Systolic & diastolic thrills in the pulmonary area Palpable systolic expansion of the pulmonary artery

PDA: Physical Findings Left parasternal heave (RVH due to PHT) Auscultation: continuous murmur in the pulmonary area (machinery murmur)

PDA: Investigations: CXR LV & LA dilatation Prominent main pulmonary artery Plethoric lungs (increased pulmonary vascular markings: arterial and venous) Prominent aorta In older patients: the ductus may be calcified

PDA: Investigations ECG: LVH tall R waves in chest leads V5 & V6 Deep S waves in chest leads V1 & V2 Echocardiography & Doppler: Demonstrates the site of the ductus and the continuous flow by Doppler

PDA: Management Closure of the ductus whatever the size Usually closed through catheterization Large ducts are closed surgically

Valvular Pulmonary Stenosis Increased resistance for RV ejection Pressure gradient between RV & PA This leads to right ventricular hypertrophy The forceful jet into the PA leads to dilatation of the main pulmonary artery

Valvular PS: Clinical Picture Raised JVP RVH: left parasternal heave Systolic thrill in the pulmonary area Faint pulmonary second sound Systolic ejection murmur at the pulmonary area

Valvular PS: Investigations ECG: RVH: tall R waves in V1 & V2 CXR: Oligemic lungs: reduced pulmonary blood flow Prominent main pulmonary artery (post-stenotic dilatation)

Valvular PS: Investigations Echocardiography: Reduced pulmonary valve motion Doppler: estimation of the gradient across the pulmonary valve

Valvular PS: Treatment Transcatheter dilatation of the stenotic pulmonary valve using a balloon inflated at the pulmonary valve If this fails: surgery

Coarctation of the Aorta Narrowing of the aorta just distal to the origin of the left SCA

Coarctation of the Aorta With age, collaterals form around the narrowing to bridge the proximal & distal parts

Coarctation of the Aorta Usually associated with bicuspid aortic valve More common in males

Coarctation of the Aorta: Clinical Co A is an important cause of congestive heart failure in neonates Often undetected during physical examination

Coarctation of the Aorta: Clinical The hallmark is radio-femoral delay of the pulse

Hypertension may cause headache Leg cramps: reduced circulation in the lower limbs

Coarctation of the Aorta: Clinical BP is raised in the arms, normal in the legs Auscultation: systolic murmur over the coarctation (heard over the back) Systolic ejection click (dilated aorta, bicuspid aortic valve) Continuous murmur from flow into collaterals: heard best over the spine

Coarctation of the Aorta: Investigations CXR: Rib notching: from enlarged collaterals Prestenotic and post-stenotic dilatation form the “3 sign” of the descending aorta

Coarctation of the Aorta: Investigations Echocardiography: Shows the site of stenosis & pressure gradient across it MRI: can show the entire extent of the aorta

Coarctation of the Aorta: treatment Early relief of obstruction: by surgery or catheter-based intervention BP returns to normal If intervention is delayed, HT may persist

Tetralogy of Fallot (TOF) The four components of TOF are: Ventricular septal defect Over-riding aorta Pulmonary stenosis, RV outflow tract obstruction Right ventricular hypertrophy

TOF: Clinical Picture Cyanosis & clubbing Squatting: sudden assumption of the sitting position in the upright patient: This increases the LV afterload and reduces the magnitude of right -to-left shunt

TOF: Clinical Picture Cyanotic spells: sudden lethargy and weakness with increased depth of cyanosis: Fever Crying Exertion Cause: Reduced pulmonary blood flow & increased shunting of blood to the left side

TOF: Physical findings Clubbing Cyanosis Prominent RV impulse No thrill (≠ valvular PS): reduced pulmonary blood flow

TOF: Physical findings Auscultation: single second heart sound Faint systolic ejection murmur at the pulmonary area

TOF: investigation ECG: Chest X ray: Right ventricular hypertrophy Right ventricular enlargement Pulmonary bay (underdeveloped pulmonary artery) The combination of these findings gives the “boot-shaped heart”

TOF: Treatment Surgical correction If the PA is very small & underdeveloped: the aorta is anastomosed to the pulmonary arteries to enhance their growth before total correction ( Blalock-Taussig shunt)