A 55-year-old man with acute inferior myocardial infarction was shown to have right ventricular involvement based on elevated jugular venous pressure, prominent A waves, and Kussmaul's sign. The ECG showed ST segment elevation in V3R with evolution of Q waves in the inferior leads. Technetium pyrophosphate images showed focal uptake in the inferior region of the left ventricle, and a radionuclide ventriculogram showed a dilated right ventricle. Administration of dobutamine, a potent inotropic agent, was associated with marked hemodynamic improvement. In contrast, the administration of diuretics was associated with hemodynamic impairment.