The slope of ST segment/heart rate relationship during exercise in the prediction of severity of coronary artery disease

Publisher Website
Google Scholar
Abstract
The results of a new excercise electrocardiography test were compared with those of coronary arteriography in 120 patients. Thirty patients were under beta-blocker therapy and 90 patients were not. In each patient the rate of progression of ST segment depression with respect to increases in heart rate was measured in 13 electrocardiographic leads; the steepest slope of regression lines relating ST segment depression to heart rate (maximal ST/HR slope) was used as an index of myocardial ischaemia. The results of coronary angiography revealed 105 patients with significant coronary artery disease (> 75% luminal narrowing); 32 patients had single-vessel disease, 43 patients had double-vessel disease and 30 patients had triple-vessel disease. Significant coronary artery disease could not be demonstrated in 15 patients. The ranges of the maximal ST/HR slope were different in the four groups of patients and the differences between the means were statistically significant (P<0.0005); these differences were maintained irrespective of beta-blocker therapy and there were no false results or indeterminate test results. In contrast using usual exercise criteria a definitive test result could not be obtained in 20 patients and there was an overlap between the four groups. It is concluded that the maximal ST/HR slope can be used reliably to predict the presence or absence and the severity of coronary artery disease in individual patients with anginal pain, whether they are on beta-blocker therapy or not.

This publication has 0 references indexed in Scilit: