Relationship between the exercise maximal ST segment / heart rate slope and coronary angiography

Objective To study the relationship between the exercise maximal ST segment/heart rate slope(ST/HR slope) and coronary angiography in patients with coronary artery disease(CHD). Methods Total 280 patients with suspected CHD received treadmill exercise test and coronary angiography in two weeks,and were divided into CHD group and non-CHD group according to the results of coronary angiography.The exercise maximal ST segment/heart rate slope and the severity of coronary arterial lesions were compared between the two groups. Results The exercise maximal ST segment/heart rate in CHD group was significantly higher than that in non-CHD group(P＜0.01),and the metabolic equivalents(METs) in CHD group was significantly lower than that in non-CHD group(P＜0.01).If ST/HR slope≥2.2 μV/(bp·min),1 branch coronary artery vessel disease accounted for 28.98%;ST/HR slope≥4.0 μV/(bp·min),2 branch coronary artery vessel disease accounted for 32.60%;ST/HR slope≥6.0 μV/(bp·min),3 branch coronary artery vessel disease accounted for 38.40%(P＜0.05).The exercise maximal ST/HR slop was positively correlated to the depression of ST segment and the severity of coronary artery lesion.The maximal(METs) was negatively correlated to ST segment depression and the severity of coronary arterial lesions. Conclusion The increase of exercise maximal ST segment/heart rate in patients with CHD may show the myocardial ischemia and the severity of coronary arterial lesions.