Usefulness of Multistage Treadmill Exercise Testing After Myocardial Infarction in Assessing the Severity of Coronary Artery Disease

Multistage treadmill exercise testing was performed in 61 patients with myocardial infarction proved significant coronary artery stenosis within six months after the acute episode.Significant ST depression developed in 35 cases (57%) and the ST depression was more frequent in inferior infarction (75%) and in those with multivessel disease (40.5%).The maximum heart rate, the maximum blood pressure and the maximum pressure-rate product were significantly low in the patients with a positive exercise test as compared to those with a negative test. The incidence of multivessel disease was 68% when the maximum pressure-rate product was less than 20, 000, while 93% when the value was less than 17, 000. On the other hand, one vessel disease could be expected when the maximum pressure-rate product exceeded 25, 000. The ventricular premature beats were frequently observed in anterior infarction and/or multivessel disease.The above findings indicate the usefulness of multistage treadmill exercise testing after myocardial infarction for the assessment of the severity of coronary artery disease.