Double outlet right atrium with three atrioventricular valves

The atrioventricular (AV) valves are complex anatomical structures which perform sophisticated functions. (1) A wide spectrum of malformations of these valves can occur in patients with AV septal defects. We here describe the anatomic and functional abnormalities of a rare form of the disease, where two valves connected the right atrium to both the right and left ventricles, in addition to a third valve that connected the left atrium to the left ventricle, with no evidence of regurgitation or cyanosis in spite of the relatively large communication between the right atrium and the left ventricle. In addition, the patient had severe subaortic stenosis. The pathophysiology, hemodynamics and method of repair of the condition are discussed.