‘Recovery only’ vs. ‘during exercise’ ST segment depression in exercise stress test – Clinical & angiographic correlation

To assess the diagnostic value of recovery-only ST segment depression in exercise stress testing by comparing the clinical and angiographic profiles of patients with ‘recovery only’ vs. ‘during exercise’ ST segment depression on exercise stress testing. 250 patients with positive exercise stress test willing for coronary angiography were selected and divided into two groups – group1 with ST segment depression during exercise and group 2 with ST segment depression during recovery phase only. Clinical and angiographic data of the groups were compared. ST segment depression during exercise phase was seen in 220 (88%) patients and during recovery phase only in 30 (12%) patients. There were no differences between the two groups in major clinical features except hypertension, which was more prevalent in those having recovery only ST depression. Significant coronary artery stenosis was found in 87.7% of exercise ST segment depression group and in 86.7% of recovery only ST segment depression group (p = 0.87). Prevalence of severe coronary artery disease (CAD) (left main and triple vessel CAD) was almost similar in the two groups. Single vessel disease was significantly more in the recovery only ST segment depression group compared to exercise ST depression group (36.7% vs. 16.4%; p = 0.012). Proximal LAD stenosis was significantly more common in the exercise ST segment depression group (39.1% vs. 20%; p = 0.045). The diagnostic value of recovery only ST segment depression is comparable to that of ST segment depression during active phase of exercise stress test.