Objective. The goal of this study was to determine the patterns of the pulmonary circulation in patients with pulmonary atresia and asplenia. Background. The asplenic cardiac syndromes characteristically have complex cardiac anomalies including pulmonary stenosis or atresia. Definition of the pulmonary artery circulation and pulmonary venous connections is needed for consideration of surgical procedures. Methods. In 35 patients, the sources of pulmonary blood flow, anatomic features of pulmonary arteries and pulmonary venous connections were determined from angiograms or autopsy specimens. Results. The pulmonary artery was absent or hypoptestic in 91% of patients; most had a ductes arteriosus. The right and left pulmonary arteries were confluent in 90% and usually of normal size (right 71%, left 63%). Total anomalous pulmonary venous connections were present in 38%. Conclusions. The anatomic features of the pulmonary arteries in pulmonary atresia associated with the asplenic cardiac syndrome are usually favorable for palliative surgical procedures. Total anomalous pulmonary venous connection may exist as a complicating factor.