Six fatal cases of primary isolated tricuspid atresia in infants have been described, and thirty-one acceptable similar cases have been collected from the literature. An abnormal superior vena cava, a right atrial Chiari's network, or both were found in the six new patients. The characteristic clinical findings of cyanosis and electrocardiographic left axis deviation aid in the diagnosis. Most patients die before 1 year of age because of congestive heart failure and anoxia.

Tricuspid atresia may be satisfactorily explained mechanically by the presence of abnormal blood currents in the primitive right atrium which allow the tricuspid ostium to close. To prolong life, surgical enlargement of the associated interauricular septal defect and creation of a systemic-to-pulmonary arterial shunt are proposed.