Abnormal Blood Pressure Response and Marked Ischemic ST–segment Depression as PrediQctors of Severe Coronary Artery Disease

The usefulness of an abnormal blood pressure response and a marked ischemic ST–segment depression during exercise testing as predictors of severe coronary artery disease was assessed in 378 consecutive patients who had a maximal symptom–limited exercise test before coronary arteriography. An abnormal blood pressure response occurred in 90 patients. The sensitivity of this response for three–vessel or left main disease was 38.6%, the specificity 87.4% and the predictive value 70%. A marked ischemic ST–segment abnormality (MIST) appeared in 85 patients. The sensitivity ofMIST for three–vessel or left main disease was 38.6%, the specificity 89.8% and the predictive value 74.1%. One hundred thirty–eight patients had either an abnormal blood pressure response or a marked ST–segment change. The sensitivity of either response for three–vessel or left main disease was 56.4%, the specificity 78.6%, and the predictive value 66.7%. Exercise duration and ejection fraction were not significantly different in patients with normal or abnormal blood pressure. We conclude that abnormal blood pressure and marked ischemic ST–segment depression during exercise testing are helpful in identifying a subset of patients with advanced coronary artery disease. The physiologic mechanism for these responses is probably exercise–induced ischemia.