Limitation of exercise-induced R wave amplitude changes in detecting coronary artery disease in asymptomatic men.

The exercise electrocardiograms of 255 asymptomatic men were analyzed for changes in R wave amplitude and ST segments. The results were correlated with findings at cardiac catheterization. There were 65 men with coronary artery disease and 190 normal subjects. R wave amplitude changes were evaluated in bipolar leads X, Y and Z. The predictive value of an abnormal ST segment response for detecting disease was only 29%. This value was improved to 42% using R wave amplitude changes with a sensitivity of 28% and specificity of 87%. Exercise-induced R wave amplitude changes enhance the specificity of detecting coronary disease in asymptomatic men over ST segment criteria alone but the sensitivity is poor and the predictive value is not enhanced. Thus, these criteria are limited in adding to the diagnostic accuracy of stress testing.