PULMONARY ATRESIA WITH INTACT VENTRICULAR SEPTUM

Abstract

This report is based on an anatomical, electrocardiographic, and clinical study of 12 cases of pulmonary atresia with an intact ventricular septum. The right ventricle was minute or small in 9 of the 12, and it was of normal size or large in the 3 remaining cases. Tricuspid malformations identifiable as various degrees of Ebstein''s malformation are commonly observed in all cases regardless of the size of the right ventricle but among these the state of competence of the tricuspid valve appeared to vary. Enlargement of the right ventricle appears to depend on the association of significant tricuspid regurgitation. Relief of obstruction of the pulmonary valve appears to promise beneficial results in cases with the right ventricle of normal size or large, but it seems useless in those with the right ventricle minute or small. In the latter group, the small size of the right ventricle limits the amount of blood that may enter the right ventricle. Distinction of cases in which the right ventricle is minute or small from those in which it is of normal size or larger depends on the radiological and cardiographic findings. Electrocardiography usually shows evidence of hypertrophy of the left ventricle in cases in which the right ventricle is minute or small, and it usually shows evidence of hypertrophy of the right ventricle or of both ventricles in cases in which the right ventricle is of normal size or larger.