Sonographic features of Ebstein anomaly associated with hydrops fetalis: a report of two cases.

Ebstein anomaly, an abnormally low insertion of the tricuspid valve, occurs in 0.5% of patients with congenital heart disease. In rare cases, this disorder may be complicated by congestive heart failure in utero and hydrops fetalis. This article reports the prenatal sonographic features of 2 cases of Ebstein anomaly associated with hydrops fetalis. In both cases, fetal echocardiography was performed at 34 weeks of gestation. The 4-chamber view showed fetal cardiomegaly and pericardial effusion. In both cases, the annular attachment of the tricuspid valve leaflets was difficult to demonstrate and so distal that it could easily be confused with papillary muscle in the right ventricular wall. Poor fetal cardiac hemodynamics with severe tricuspid regurgitation was demonstrated by pulsed Doppler imaging. Pulmonary regurgitation was also clearly demonstrated in both cases. Preterm delivery with stillbirth occurred in both cases. Autopsies confirmed the very distal displacement of the tricuspid valve insertion, close to the apex, and enlargement of the right atrium.