The study has been carried out on eight cases of pulmonary atresia with ventricular septal defect, this abnormality involves both valvular atresia and the stenosis of the outflow tract of the right ventricle; that means a pulmonary atresia both valvular and infundibular. The atresia is always combined with a dextroposition of the aorta, overriding the ventricular septum; often with an auricular septal defect or a patency of the foramen ovale. In two cases, other associative caridac malformations exist : either a single ventricle or an atresia of the tricuspid valve. The arterial supply to the lungs may be assured by a persistent duct or by systemic arteries, or an association of both.