Accuracy of Fetal Echocardiography in Defining Pulmonary Artery Anatomy and Source of Pulmonary Blood flow in Pulmonary Atresia with Ventricular Septal Defect (PA/VSD).

Precise delineation of central and branch pulmonary artery anatomy, patent ductus arteriosus, and major aorto-pulmonary collateral artery anatomy in the fetal diagnosis of pulmonary atresia with ventricular septal defect is challenging but important to prenatal counseling and postnatal management. We aimed to evaluate the accuracy of fetal echocardiography to determine these anatomical nuances in pulmonary atresia with ventricular septal defect. This was a retrospective, single-institution, 10-year chart review of consecutive prenatal diagnosis of pulmonary atresia with ventricular septal defect for assessment of pulmonary artery, patent ductus arteriosus, and major aorto-pulmonary collateral artery anatomy and comparison with postnatal imaging including echocardiography, cardiac catheterization, and computerized tomography angiography. Twenty-six fetuses were diagnosed with pulmonary atresia with ventricular septal defect during the review period and complete postnatal follow-up was available in 18, all confirming the basic prenatal diagnosis. Fetal echocardiography accurately predicted central and branch pulmonary artery anatomy in 16 (89%) [confluent in 14, discontinuous in 2], patent ductus arteriosus status in 15 (83%) [present in 10, absent in 5], and major aorto-pulmonary collateral arteries in 17 (94%) [present in 9, absent in 8]. Accuracy increased to 100% for pulmonary artery anatomy (16/16) and major aorto-pulmonary collateral artery (17/17) when excluding patients whose anatomy was reported as uncertain on fetal echocardiography. Fetal echocardiography can provide accurate anatomical details in the vast majority of fetuses with pulmonary atresia with ventricular septal defect. This allows for more anatomy-specific counseling, prognostication, and improved selection of postnatally available management options.