ST Segment Elevation in Lead V1on Treadmill Exercise Test in the Patients with Angina : A Predictor of Coronary Artery Disease and It's Location

ABSTRACT

OBJECTIVES: To assess the relationship between ST segment elevation during exercise testing and coronary artery disease. METHODS: Treadmill exercise electrocardiography and coronary angiography were performed in 137 patients with angina with no Q waves. The J point elevation of > 0.03mV(0.3mm) measured from baseline, the elevation of ST segment at 80msec. from J point(ST80) measured larger in lead V1than in aV1, or both the elevation of ST segment at J point and at ST80 developed earlier than or concomitantly with ST depression were considered as abnormal responses. RESULTS: 1) There was no clinical significance of ST elevation in lead aV1. 2) Exercise-induced ST elevation in lead V1occurred in 29 of 137 patients with angina. 3) Abnormal St elevation in V1was detected in 26 of 86 patients with coronary artery disease, for a specificity of 98%. The patients with left anterior descending coronary artery or left main coronary artery stenosis were observed in 3 of 5(60%) patients with single-vessel disease, in 7 of 9(79%) with two-vessel disease, and in 9 of 10(90%) with three-vessel disease. 4) The standard ST depression yielded a specificity of 55% in the patients with isolated or predominant ST depression in inferior leads(II. III, and aVF) and of 81% in the patients with isolated or predominat ST depressin in precordial leads(p<0.001). 5) Abnormal exercise-induced ST elevation in V1was detected in 13 of 39(33%) patients with isolated or predominat ST depression in inferior leads and yielded a specificity of 94% for coronary artery disease. CONCLUSION: Abnormal ST segment elevation in V1may increase the specificity in isolated or predominat ST segment depression in inferior leads and may predict left anterior descending or left main coronary artery disease.