Aortopulmonary window, (partial truncus arteriosus or aortopulmonary septal defect) is a rare congenital conotruncal cardiac anomaly with communication between the ascending aorta & the main or right pulmonary artery. It is caused by incomplete division of the embryonic common trunk. The two semilunar valves are usually separately identified and the absence of VSD differentiates it from truncus arteriosus. Association with PDA in 15%. Aortopulmonary window is associated with VSD or aortic coarctation.

In this case, interrupted aortic arch is seen with a large PDA is giving the descending aorta.

The Case is courtesy of Dr. Mohammad A. ElBeialy, MD, FRCR & Dr. Heba Kamal.