"Recovery only" ST-segment depressions are sometimes detected during an exercise treadmill test. We undertook this study in order to clarify the predictive value of exercise-induced ST-segment depression occurring in recovery only.

The study included 931 patients who had both a sign or symptom -limited treadmill test. Of the 66 patients who demonstrated abnormal ST-segment responses, 43 experienced ST-segment depressions during exercise (Group A) and 23 displayed such responses only during recovery (Group B).

The positive predictive value of an exercise treadmill test for significant angiographic disease in group A (81.3%) was statistically different from the predictive value in group B (30.4%). Horizontal ST-segment depression in recovery periods and female sex were statistically significant factors favoring negative coronary angiographic results.

The occurrence of horizontal mild ST-segment depression during only the recovery periodgenerally represents a "false positive" response, particularly in female patients.