Significance of ⁹⁹Tc^m-MIBI gated myocardial perfusion imaging in patients with type 2 diabetes but without myocardial ischemia symptoms

Objective: To explore the significance of ⁹⁹Tc^m-MIBI gated myocardial perfusion imaging in patients with type 2 diabetes but without myocardial ischemia symptoms. Methods: Eighty-three patients with confirmed type 2 diabetes represented the test group and underwent ⁹⁹Tc^m-MIBI gated myocardial perfusion imaging; 51 patients with neither type 2 diabetes nor history of cardiovascular diseases represented the control group and underwent the same examination. Each image of the left-ventricle myocardium was divided into 17 segments for semi-quantitative analysis. All the segments were evaluated in consensus by two experienced doctors. Results were scored using a five-point scoring system and then referred to the system software's auto-scores. The summed stress score(SSS), summed rest score(SRS), summed difference score(SDS), left ventricular ejection fraction (LVEF), peak perfusion rate, and peak ejection rate were determined during both stress imaging and rest imaging. Results: Nonreversible defects were not observed in the segments obtained from the two groups. However, the difference between the abnormal perfusion segments of the two groups was significant(χ² = 24.19, P < 0.05); the difference between the SSS and SRS(t = 7.13, 3.15, P < 0.05) of the two groups was also significant, but no difference was noted in the SDS(t = 1.44, P > 0.05) of both groups. Moreover, no significant difference existed between the SSS and SRS in the control group(t = 1.795, P > 0.05). By contrast, the difference in the post-stress LVEF between the two groups was significant(t = -7.65, P < 0.05). Conclusions: Even without cardiac symptoms, patients with type 2 diabetes should undergo ⁹⁹Tc^m-MIBI gated myocardial perfusion imaging for further analysis. (authors)