Aim: The purpose of our study was to assess the efficiency of the two tests (exercise ECG test and myocard perfussion test) to determine the silent myocardial ischemia in diabetic patients and compare the two tests with each other.

Method: 97 follow-up diabetic patients, who had no known coronary artery diseases, or no defined rest dyspnea or effort dyspnea were included in the study. While 44 patients, who were arbitrarily chosen, were subjected to exercise ECG, 53 were subjected to thallium myocardial perfusion scintigraphy.

Result: 4 of the 44 patients subjected to effort tests, and 7 of the 53 patients subjected to thallium scintigraphy revealed positive test results. These patients whose test results were positive, were administered coronary angiography so that SMI was verified. 2 of the 4 patients with positive effort test, thallium scintigrapy was positive, and 6 of the 7 patients with positive thallium scintigraphy revealed ischemia compliant coronary angiography. Accordingly, in our study, the SMI frequency determined by non-invasive tests (effort, thallium) was 9.1% in the group subjected to effort test, 13.2% in the group subjected to thallium scintigraphy, and 11.3% considering all patients together. The SMI frequency that could be verified by coronary angiography is 4.5%, 11.3% and 8.2% respectively. Hence, the false positivity ratio of the effort test is 50.0% while that of the thallium scintigraphy is 14.3%, the positive predictive value of the effort test is 50.0%, and that of the thallium scintigraphy is 85.7%

Conclusion: We could not determine the statistical superiority of the effort test to thallium myocardial perfusion scintigraphy for the purpose of SMI diagnosis. In such a case, the easily available and cost effective exercise ECG test could be considered as a better choice for SMI verification. But from the numerical point of view, we could be able to diagnose more patients with SMI using thallium scintigraphy and found much higher positive predictive value of the thallium test in comparison to the effort test. If the number of patients are increased, we believe that thallium scintigraphy could be seen superior to the effort test from statistical point of view.

Diabetes mellitus Silent myocardial ischemia Myocardium perfusion scintigraphy Exercise electrocardiography test