Aortopulmonary septal defect


Aortopulmonary septal defect (APSD), also known as aortopulmonary window (APW), is a cardiac abnormality that results from abnormal communication between the proximal aorta and the main pulmonary artery.  It is an uncommon anomaly, occurring in less than 1% of all persons with a congenital heart disease.  It has similar hemodynamic features to a patent ductus arteriosus, ventricular septal defect, or, even more so, to a common truncus arteriosus, the anatomical difference from the latter being the presence of separate well-defined aortic and pulmonary valves. 

This term should not be confused with the radiologic aortopulmonary window (AP window), which refers to a mediastinal space on chest radiographs and CT scans.