Communication between the right pulmonary artery and left atrium with aneurysm formation.

Communication between the pulmonary artery and the left atrium is a rare congenital anomaly. A 7-year-old boy was referred to our hospital with a diagnosis of pulmonary arteriovenous fistula. Referral to a pediatric cardiologist had been delayed because he had only slight cyanosis and no heart murmur. Catheterization and computed tomography scans confirmed that the right pulmonary branches and pulmonary venous returns were normal and that an additional aneurysmal communication was located between the right pulmonary artery and the left atrium. Surgery proceeded uneventfully together with a cardiopulmonary bypass. The connection from the right pulmonary artery to the aneurysm was ligated, and the connection from the left atrium to the aneurysm was closed with a polytetrafluoroethylene patch. We describe this rare anomaly with cyanosis and no heart murmur.