Prenatal Diagnosis of Pulmonary Atresia With Intact Ventricular Septum

Pulmonary atresia with intact ventricular septum is a rare and complicated congenital cardiac anomaly. Pulmonary outflow is obstructed, which results in hypertrophy and hypoplasia of the right ventricle. The fetal echocardiographic findings include a small pulmonary artery with an atretic pulmonary valve, right ventricular hypertrophy, dilated right atrium, and absent flow in the pulmonary artery on Doppler interrogation. The left ventricle, left atrium, and aortic root also may be enlarged. Nonimmune hydrops may develop in utero, which is the result of poor left ventricular function. Surgical treatments vary, depending on the presence of associated cardiovascular anomalies, but generally include a systemic-to-pulmonary artery anastomosis and a pulmonary valvulotomy.