Right ventricular infarction mimicking extensive anterior infarction.

Two patients with inferior infarction complicated by right ventricular infarction are presented. Both manifested electrocardiographic changes involving the anterior chest leads with initial S-T segment elevation followed by loss of R waves and the development of QS complexes mimicking anterior infarction. Cardiac catheterization showed right coronary artery occlusion with normal left coronary system and anterior wall motion in each case. Radionuclide angiocardiography showed dilated poorly contracting right ventricles. The ECG changes of "anterior infarction" in these patients were therefore due solely to right ventricular injury.