[en] Fifty patients were prospectively evaluated for myocardial ischemia utilizing treadmill testing and thallium-201 imaging. By coronary angiography, 43 had significant coronary stenosis and seven were normal. The sensitivity, specificity, accuracy and predictive value of treadmill testing alone did not statistically differ from that of thallium-201 imaging. Combined treadmill testing and thallium-201 imaging did not significanlty affect the results of treadmill testing alone. Thallium-201 imaging failed to identify a number of patients with high risk lesions. The use of thallium-201 imaging as a routine screening procedure for myocardial ischemia in patients with typical angina, without due consideration of the prevalence of the disease in the population, is not justified