ST DEVIATION IN RIGHT CHEST LEADS V3R TO V7R DURING PERCUTANEOUS TRANSLUMINAL CORONARY ANGIOPLASTY

ST elevation in right chest leads during evolving inferior myocardial infarction indicates righ ventricular involvement. Theoretically, such changes may be due to reversible or irreversible myocardial ischemia. Whether similar ST elevations can be recorded in patients with myocardial ischemia without infarction is unknown. To clarify this, right chest leads V3R to V7R were recorded during percutaneous transluminal coronary angioplasty in 43 patients who had a total of 45 arteries dilated. Balloon occlusion of the right coronary artery caused transient ST elevation, whereas closure of the left anterior descending coronary artery or the left circumflex artery was associated with transient ST depression. These findings were 100% discriminative in leads V5R and V6R. Furthermore, ST elevation greater than or equal to 1 mm in one or more of leads V4R to V7R was seen only when the right coronary artery was occluded. Thus transient myocardial ischemia without infarction may cause ST elevation in the right chest leads and ST elevation greater than or equal to 1 mm in one or more leads V4R to V7R is seen exclusively with occlusion of the right coronary artery. © 1990.