Delayed appearance of left-to-right shunt following aortic valvular replacement. Report of two cases

Two cases are presented in which a left-to-right shunt occurred late following aortic valvular replacement. In one patient a fistula was found between the aortic root and the right atrium and ventricle. In the second patient a defect developed in the membranous septum, allowing shunting from the left ventricle to both the right atrium and right ventricle.