Syndrome of Left Ventricular-Right Atrial Shunt Resulting from High Interventricular Septal Defect Associated with Defective Septal Leaflet of the Tricuspid Valve

Two similar cases of unusual congenital anomalies of the heart are presented, in which there existed a direct communication between the left ventricle and the right auricle through a defect involving the membranous portion of the interventricular septum with defective formation of the medial leaflet of the tricuspid valve. Data obtained at catheterization, operative and postmortem findings are presented in each case. The differential diagnosis of this type of lesion is discussed.