PREDICTIVE VALUE OF STRESS ECG PARAMETERS FOR MYOCARDIAL-ISCHEMIA ACCORDING TO (201)THALLIUM TEST

Background: Exercise EKG is used as the test of choice in the diagnosi s of coronary artery disease. Classical parameters are angor and ST de pression representing myocardial ischemia. Aim: To correlate exercise EKG parameters with SPECT (201)Thallium to their likelihood ratios for ischemia. Patients and methods: Two hundred seventy four patients (17 1 men), aged 58 years old as a mean, were studied. Of these 23% had a prior myocardial infarction. The likelihood ratios for the presence of ischemia of ST depression, failure to increase blood systolic pressur e, the presence of angor and its duration during stress testing were c alculated according to the results of SPECT (201)Thallium. Seventy one patients were also subjected to a coronary angiography. Results: Amon g men, likelihood ratios for the presence of angor, failure to increas e systolic pressure, ST alterations and duration of angor were 6.9, 6. 15, 1.77 and 1.27 respectively. Among women, the figures were 5.45, 1. 77 0.58 and 1.4 respectively. The diagnostic accuracy of SPECT (201)Th allium, when correlated with the results of coronary angiography, was 85%. Conclusions: Among men, the best exercise EKG predictors for myoc ardial ischemia were the failure to increase systolic blood pressure a nd the presence of angor. Among women the only significant predictor w as the presence of angor.