Ebstein Anomaly

Ebstein anomaly (EA) is a relatively rare congenital heart lesion (1% of CHD) with failure of tricuspid delamination, apical displacement of the tricuspid valve (TV), and myopathy of the right ventricle (RV). Anatomic and clinical presentation are highly varied; mortality is high in the neonatal period while late survival is seen in patients diagnosed in late childhood or adulthood. Neonates frequently present in extremis with cyanosis and severe heart failure. Indications for operation in neonates includes inability to wean from ventilator, severe heart failure, persistent metabolic abnormalities, persistent cyanosis, prostaglandin dependence, and cardiothoracic ratio >80%. Patients may progress down single ventricle or biventricular treatment pathways. When operative intervention is required in the neonatal period, early mortality is approximately 25%. During childhood and adulthood, surgery is considered when symptoms develop or exercise capacity is reduced or with cyanosis, paradoxical embolus, or progressive RV dilatation or dysfunction. Patients may proceed down biventricular or 1.5 ventricular pathways with bidirectional cavopulmonary shunt. Goals of surgery include anatomic TV repair, plication of atrialised portion of RV, right atrial reduction, and closure/subtotal closure of interatrial connections. Successful TV repair is more likely in patients with mobility of the anterior leaflet and less likely with severe muscularisation of leaflet tissue and absence of septal and inferior leaflet tissue. TV replacement is considered in older patients and those with pulmonary hypertension or left ventricular dysfunction; bioprostheses are generally used. Late freedom from reoperation and survival are quite favourable.