The role of Tc-99m MIBI gated myocardial perfusion scintigraphy in the investigation of coronary artery disease in patients with type 2 diabetes mellitus

AIM: In this study, we aimed to evaluate diagnostic value of ECG gated Tc-99m sestamibi MPS in detection of coronary artery disease, and contribution of parameters relevant to left ventricular function and microvascular coronary circulation to MPS in a diabetic population. MATERIALS AND METHODS: We applied single-day rest-stres ECG gated MPS on 38 diabetic patients over 50 years of age, with DM durations longer than 10 years, without hypertension, cigarette smoking, known coronary artery disease or previous myocardial infarction; and an age-matched control group of 19 patients with low-risk for coronary artery disease. Using myocardial counts obtained from SPECT data and injected amounts (mCi) of Tc-99m sestamibi, we calculated the relative increase in myocardial counts during exercise in comparison to rest conditions, as %IR. RESULTS: MPS revealed myocardial ischemia in 5 diabetic patients (%13; 5/38). Coronary angiography was applied in three of them and revealed subcritic (<70%) coronary artery stenosis concordant with MPS findings. None of the diabetic patients with normal MPS findings developed coronary artery disease in the follow-up period of 10,8 ± 4,2 months. No significant differences were observed between two groups with respect to calculated %IR values and left ventricular functional parameters. CONCLUSION: In patients with DM, presence of coronary artery disease could be detected in an early period using Tc-99m sestamibi ECG gated MPS. However, in this patient population, calculation of additional parameters relevant to left ventricular function and microvascular coronary circulation did not seem to contribute to MPS in diagnosis of coronary artery disease.