Postexercise systolic blood pressure response: clinical application to the assessment of ischemic heart disease

Stress test parameters indicating the presence and extent of coronary artery disease have traditionally included such variables as exercise duration, and the blood pressure and ST-segment responses to exercise. The three-minute systolic blood pressure ratio, another important indicator of significant coronary artery disease, is a useful and readily obtainable measure that can be applied in all patients who are undergoing stress testing for the evaluation of known or suspected ischemic heart disease. The ratio is calculated by dividing the systolic blood pressure three minutes into the recovery phase of a treadmill exercise test by the systolic blood pressure at peak exercise. A three-minute systolic blood pressure ratio greater than 0.90 is considered abnormal and has a diagnostic accuracy of approximately 75 percent for the detection of coronary artery disease (i.e., an accuracy comparable to that of ST-segment depression). Higher values for the ratio are associated with more extensive coronary artery disease, as well as an adverse prognosis after myocardial infarction. Thus, the three-minute systolic blood pressure ratio provides information that is complementary to the traditional exercise test parameters for identifying high-risk ischemic heart disease.