Electrocardiographic changes in right ventricular infarction. A case report.

ST segment elevations in leads CR4R or V4R indicating right ventricular (RV) involvement are sometimes seen in patients with acute inferior transmural infarction. Whether the RV lesion per se or the concomitant infarction of the posterior septum causes this ECG pattern is unknown. We describe a patient with anteroseptal transmural infarction who developed unusually marked ST segment elevations in lead V4R. At autopsy, extensive old fibrotic infarction was found, involving the anterior and lateral RV walls, as well as recent necrosis of the interventricular septum. These findings suggest that the ST segment elevation in V4R in patients with RV infarction may not be caused by the RV necrosis per se but rather by visualization of the posterior septum through the necrotic RV myocardium.