Right sided chest lead electrocardiographic abnormalities in acute pulmonary embolism.

Twelve lead electrocardiograms together with right-sided chest leads V4R, V5R and V6R were recorded in four patients with acute pulmonary embolism. All four patients showed ST segment elevation and a qs or qr pattern (with prominent q waves) in one to three of the leads V4R, V5R and V6R. These abnormalities were absent in the repeat electrocardiograms which were recorded after the acute illness.