Distal aortopulmonary septal defect, aortic origin of the right pulmonary artery, intact ventricular septum, patent ductus arteriosus and hypoplasia of the aortic isthmus: a newly recognized syndrome.

The association of distal aortopulmonary septal defect, aortic origin of the right pulmonary artery, intact ventricular septum and interruption or coarctation of the aortic isthmus has not previously been reported as a syndrome. This combination of anomalies was encountered in five new patients and was previously reported in three. Two patients have undergone surgery with successful results. In contrast to the sagittally oriented conventional proximal aortopulmonary septal defect, the patients in this series had a more distal type of defect, possibly representing a partial persistence of the common arterial trunk. The pulmonary arterial bifurcation may malattach to this undivided truncal segment and, as a result, the right pulmonary artery may be partially or completely shifted into the aorta. This abnormal right pulmonary arterial origin may lead to "steal" from the aortic flow during embryogenesis and to hypoplasia of the aortic arch. This concept is supported by the angiographic observation that the greater the rightward displacement of the right pulmonary artery, the greater the hypoplasia of the arch. The diagnostic angiographic sign is a strikingly high origin of the right pulmonary artery together with aortic arch hypoplasia or atresia. Closure of the aortopulmonary septal defect with implantation of the right pulmonary artery in the pulmonary trunk and repair of the aortic arch anomaly is the recommended surgical treatment.