Clinical significance of exercise-induced ST-segment elevation in patients without previous myocardial infarction

Objective: To study the lesion characters of coronary artery and optimal treatment of patients without previous myocardial infarction who developed an exercise induced ST segment elevation. Method: Six patients without previous myocardial infarction who developed ST segment elevation during exercise testing were underwent coronary angiography and rest electrocardiography, and Bruce protocol were used during exercise test. Result:The incidence of exercise induced ST segment elevation was 0.21 %(6/2 864). ST segment elevated 0.1 ～ 1.0 mV in relevant leads during exercise testing. One of the 6 patients had only a mild coronary stenosis ( 35% in diameter) in left anterior descending artery, but she developed an acute myocardial infarction 4 weeks after coronary angiography. Correspondly, the leads of myocardial infarction were found the same as the leads of exercise induced ST segment elevation. The others all had severe coronary stenosis (90%～100%). There was a good correlation between leads of ST segment elevation and related ischemic artery, and percutaneous transluminal coronary angioplasty (PTCA) was safe and effective. Also, these patients showed no negative results of exercise testing after PTCA. Conclusion: The findings indicates that patients developed exercise induced ST segment elevation without no previous myocardial infarction often have severe coronary stenosis and poor prognosis, and acute coronary syndrome should be diagnosed, and PTCA is safe and effective for these patients