Anomalous Origin of Left Pulmonary Artery From the Ascending Aorta

A patient whose left pulmonary artery arose from the ascending aorta is described. The embryology and a review of the literature concerning this unusual anomaly is presented. This is the third reported case of an anomalous origin of the left pulmonary artery without associated intracardiac defects and the sixth one successfully corrected. This patient presented the interesting opportunity to compare histologically the ef fects of having one lung connected to the lesser circulation and the other to the systemic circulation in the same patient. The severe cardiac symptoms usually en countered and the otherwise fatal outcome makes surgical correction of this lesion mandatory.