A case of Uhl's anomaly in a newborn who died in congestive cardiac failure at 18 days of age is described. There was severe cardiomegaly on chest X-ray, right atrial hypertrophy on E.C.G., and a delayed tricuspid valve closure of 0,8 seconds on M-mode echocardiogram. The necropsy study showed a huge right atrial and right ventricular dilatation, a very thin right ventricular wall (1 mm.) with an important reduction in the number of muscular fibers, a pulmonary valve atresia, and a patent ductus arteriosus and foramen ovale. We have only three cases Uhl's anomaly associated with pulmonary atresia, and no one with such an important delay of the tricuspid valve closure on the echocardiogram.