Exercise-induced QRS changes (Athens QRS score) in patients with coronary artery disease: a marker of myocardial ischemia.

Previous studies have shown a good correlation between exercise-induced changes of Q-, R-, and S-waves (Athens QRS score) and the number of the obstructed coronary arteries. The present study was undertaken to test the hypothesis that abnormal Athens QRS score is related to exercise-induced myocardial ischemia. Patients who had exercise radionuclide ventriculography (n = 150) or thallium-201 scintigraphy (n = 124) within 1 month of cardiac catheterization were studied. Athens QRS score was calculated based on the exercise-induced changes of the Q-, R-, and S-waves. Changes in Athens QRS score were compared to the number of obstructed coronary arteries, segmental contraction abnormalities, and exercise-induced myocardial perfusion defects. Athens QRS score and coronary artery disease: The Athens QRS score was decreased as the number of obstructed coronary arteries increased (normal coronary arteries 3.7 mm, confidence interval 1.0 to 3.9, one vessel disease 1.2 mm, two vessel disease -0.6 mm, three vessel disease -1.3 mm, p < 0.001). Athens QRS score and segmental contraction abnormalities: The Athens QRS score decreased as the number of segmental contraction abnormalities increased (no segmental contraction abnormalities 2.5 mm, confidence interval 1.0 to 3.9, one segmental contraction abnormality -0.4 mm, two segmental contraction abnormalities -1.5 mm, three segmental contraction abnormalities -2.6 mm, p < 0.001). Athens QRS score and reversible myocardial perfusion defects: The Athens QRS score was decreased as the number of exercise-induced myocardial perfusion defects increased (no perfusion defect 2.4 mm, confidence interval 0.9 to 3.9, one perfusion defect -0.7 mm, two perfusion defects -2.6 mm, three perfusion defects -3.3 mm, p < 0.001). Abnormal values of the Athens QRS score were better correlated with the number of exercise-induced segmental contraction abnormalities or the myocardial perfusion defects than the number of obstructed coronary arteries (p < 0.001). Exercise-induced changes in Athens QRS score were directly related to the number of obstructed coronary arteries, to exercise-induced segmental contraction abnormalities and to exercise-induced myocardial perfusion defects. However, Athens QRS score changes were more closely related to the number of exercise-induced segmental contraction abnormalities or to the exercise-induced myocardial perfusion defects than to the number of obstructed coronary arteries. The data suggest that exercise-induced QRS changes, Athens QRS score are related to exercise-induced myocardial ischemia.