Method: 128 patients were studied (61F, 67M, mean age 58years), 57diabetic, 71non-diabetic, all of them with suspected CAD. All patients underwent gated SPECT myocardial perfusion imaging in stress and rest (two days protocol) and coronary angiography. We used physical stress in 81patients and dipiridamol stress protocol in 47. Acquisition has been made after iv injection of 99mTc sestamibi respecting the two days protocol, by using a dual head gamma camera Philips Axis. Images were assessed by two specialists in our department. Perfusion defects on stress images were considered “irreversible” if remained unchanged on the rest images, and “reversible” if they were new or worsening after stress imaging. ECG gating procedure allowed us to distinguish between a fixed defect and an artifact. Based on coronary angiography we defined significant CAD as luminal stenosis of >50% in one or more of the coronary arteries.

Results: 33/57(57.89%) diabetic patients had significant CAD, according to coronarografic criteria (group A). 24/57 diabetic had non-significant CAD (group B). In the group of nondiabetic patients 32/71 (45.07%) had significant CAD (group C) and 39/71 of nondiabetic patients had no significant CAD. Myocardial perfusion defects were detected at 31 of 33 patients in group A (93.9%), 3 of 24 in group B (12.5%), 29 of 32 in group C (90.6%), 3 of 39 in group D (7.69%). Irreversible defect were found in 27 patients in groupA(81%), and in 21 patients of groupC(65%). No patient without significant CAD (groups B and D) showed irreversible perfusion defects.

Conclusions: Our results suggest that among patients with suspected CAD, significant disease can be demonstrated in a greater percent at diabetics vs. nondiabetics (57.89% vs. 45.07%). We can also conclude that at diabetic patients the number and severity of myocardial perfusion defects is greater than in nondiabetics. Myocardial perfusion SPECT showed a greater percentage of irreversible defects at CAD diabetic patients (81% vs. 65%). We can consider myocardial perfusion SPECT with 99mTc-MIBI as a feasible method for diagnosis and evaluation of CAD and for the management of diabetic patients.