Atrioventricular canal is a very complex congenital endocardial cushion defect that consist of a primum atrial septal defect and a av canal type of ventricular septal defect.
May be associated with a cleft mitral valve
. Surgical repair is the treatment. The timing will depend on severity of shunting, the presence or absence of a concomitant right ventricular outflow obstruction and other factors.