Clinical presentation of a myocardial rhabdomyosarcoma.

A case initially diagnosed as tricuspid insufficiency in which critical review of the clinical findings pointed to a diagnosis of pulmonary outflow obstruction is described. At necropsy a myocardial rhabdomyosarcoma was found with associated thromboembolism. The cardinal features were the rapid development of a loud systolic murmur, clinical evidence of right ventricular enlargement and failure with large jugular presystolic 'a' waves, and a reduction in the intensity of the pulmonary component of the second sound, a shift in the QRS axis to the right, and an increase in the cardiothoracic ratio.