Endocardial Cushion Defect - Pathophysiology, Clinical findings And Management

Pathophysiology
– When both ASDs and VSDs occur, which are contiguous, and the atrioventricular valves are abnormal
Left-to-right shunt at both atrial and ventricular levels; some right-to-left shunting with desaturation (mild, intermittent cyanosis)
Atrioventricular valve insufficiency –+ increase volume load on one or both ventricles; early heart failure, infections, minimal cyanosis, hepatomegaly, and failure to thrive.

Physical examination
Heart failure early in infancy (hepatomegaly, failure to thrive)
Eisenmenger physiology occurs earlier
– Moderate-to-severe increase in heart size with hyperdynamic precordium (precordial bulge and lift)
– Loud S1 widely fixed split S2 (like an isolated ASD)
Pulmonary systolic ejection murmur, low-pitched diastolic rumble at left sternal border and apex; may also have mitral insufficiency (apical harsh holosystolic murmur radiating to left axilla).

Diagnostic tests
Chest x-ray- shows significant cardiomegaly, increased pulmonary artery and pulmonary blood flow and edema.
– ECG-signs of biventricular hypertrophy, right atrial enlargement, superior QRS axis
– Echocardiogram (gold standard).

Treatment

- surgery more difficult with heart failure and pulmonary hypertension (increased pulmonary artery pressure by 6-12 months of age); must be performed in infancy.

Complications– Without surgery-death from heart failure
– With surgery-arrhythmias, congenital heart block