Congenital pulmonary atresia with tricuspid insufficiency: morphologic study.

In an anatomic study of 21 cases of pulmonary atresia with tricuspid insufficiency (pulmonary atresia with intact ventricular septum, type II), the morphologic features of the tricuspid valve and the right ventricle were found to differ greatly from those seen in pulmonary atresia with tricuspid stenosis (pulmonary atresia with intact ventricular septum, type I). Morphologically, pulmonary atresia with tricuspid insufficiency (type II) has a greater resemblance to Ebstein's disease with pulmonary atresia than to type I pulmonary atresia. The anomaly may be more amenable to surgery than pulmonary atresia with tricuspid stenosis because the right ventricle in the former may be converted into a functional chamber by a valvotomy combined with a shunting procedure and atrial septostomy.