The relation between treadmill exercise testing and ambulatory ST segment monitoring in detection of ischemia in patients with coronary artery disease has not been well established, with pathophysiologic mechanisms underlying the development of ischemia in the ambulatory setting not being well elucidated. This study was performed to determine the relation between myocardial ischemic indexes on exercise testing and on Holter monitoring.

We analized 25 patients with stable angina and angiographically documented coronary artery disease, who exhibited ischemia both on a Bruce protocol exercise test and on 24-hr Holter monitoring while receiving routine antianginal medications.

Mean heart rate at the onset of 1mm ST segment depression during exercise testing(74.4 VS 114.1 beats/min, p<0.01). Overall the correlations between ischemic indexes on both test were weak. But heart rate at the onset of ischemic episodes during Holter monitoring had a good correlation with heart rate at 1mm ST depression during exercise test. And the number of ischemic episodes on Holter monitoring revealed a weak negative correlation with duration of exercise during treadmill test.

Ischemic indexes on exercise testing cannot accurately predict ischemic indexes on Holter monitoring in patients with coronary artery disease. In that regard, Holter monitoring may provide other clinical information in addition to that obtained by exercise testing in selected patients.