title: Analysis of exercise-induced R wave amplitude changes in detection of coronary artery disease in asymptomatic men with left bundle branch block.
abstract: The exercise electrocardiograms of 44 asymptomatic men with acquired left bundle branch block were analyzed for changes in R wave amplitude. Results were correlated with findings on selective coronary angiography. There were two subgroups: 7 men with significant angiographic coronary artery disease (Group I) and 37 with normal coronary angiograms (Group II). Exercise induced an increase in R wave amplitude in all seven men with coronary artery disease but in only 10 of the 37 men without significant coronary artery disease. This criterion thus had a sensitivity of 100 percent but a poor specificity of 73 percent, a predictive value of 41 percent and an accuracy rate of 77 percent for the diagnosis of coronary artery disease. The greater the increase in R wave amplitude the greater was the likelihood of some degree of left ventricular dysfunction as measured by wall motion abnormalities and elevated left ventricular end-diastolic pressure. The increase in R wave amplitude with exercise appears to be a sensitive test in identifying coronary artery disease in asymptomatic men with acquired left bundle branch block.
mesh_terms: D000328:Adult; D001794:Blood Pressure; D002037:Bundle-Branch Block / Q000150:complications*; D003327:Coronary Disease / Q000150:complications / Q000175:diagnosis* / Q000000981:diagnostic imaging; D004562:Electrocardiography; D005080:Exercise Test; D006339:Heart Rate; D006352:Heart Ventricles / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption; D011859:Radiography