Abstract
Two cases of isolated incompetence of the pulmonic valve diagnosed during life are reported and a review of the literature is presented. The diagnosis should be suspected in patients with a basal diastolic murmur and right ventricular enlargement who have no evidence of other cardiac valvular disease. The characteristic murmur associated with isolated incompetence of the pulmonic valve appears to be related to filling of the dilated right ventricle. The diagnosis can be confirmed clinically by right heart catheterization. The lesion is not benign in the human being, and right ventricular failure may be precipitated when complicating diseases are present.