Critical appraisal of exercise variables: a treadmill study

Background New criteria for diagnosing ischemic response to treadmill exerc ise testing (TET) have continuously been proposed. Simultaneous comparison of test performances according to these criteria is likely contributory to interpreting TET and needs to be updated time after time, This study was co nducted to accomplish this end, Methods A comparison of test performances of various TET variables for a co hort of 107 clinical normals and 139 angiographic patients with normal rest ing electrocardiograms was performed. Angiographic references included enum eration of diseased coronary vessels, Gensini's and Duke's coronary scores, left ventricular wail motion score and ejection fraction at rest Results The ST-segment-related variables (depression, integral, and heart-r ate-adjusted slope or index) outdid non-ST-segment variables (changes in R amplitude, the Athens QRS score, peak exercise blood pressure increment and recovery pressure ratios; most P <0.05) in diagnosing coronary artery dise ase. Among them the heart-rate-adjusted ST-segment depression performed sti ll better, This trend was not evident in identifying left main and three-ve ssel disease, However, correlation to the coronary scores favored the ST-se gment-related criteria (r = 0.18-0.39, P<0.05 to P<0.001 versus r = 0.05-0. 23, NS to P< 0.01) for evaluating severity of coronary artery disease. Conclusions For patients with normal resting electrocardiograms, the adjust ment of ST-segment depression for heart rate is valuable for evaluating cor onary artery disease. Coronary Artery Dis 10:15-22 (C) 1999 Lippincott Will iams & Wilkins.