Purpose  

Diabetic patients have a high risk for cardiovascular events. The role of myocardial perfusion imaging was investigated in asymptomatic diabetic patients to evaluate short-term prognosis in a Japanese population.

Methods  

A total of 506 asymptomatic patients ≥50 years of age who had carotid artery maximum intima-media thickness ≥1.1 mm, urinary albumin excretion of ≥30 mg/g creatinine, with additional criteria of abdominal obesity, low HDL cholesterol, high triglyceride level, and hypertension were enrolled and followed up over a 3-year period. Gated SPECT with stress-rest protocol was performed and analyzed by summed defect scores and QGS software. One-year cardiovascular events were analyzed.

Results  

Myocardial ischemia was observed in 17% of patients, and abnormal perfusion findings of ischemia and/or scar were observed in 32% of patients. By the end of the 1-year follow-up, 33 (6.5%) cardiovascular events occurred including 6 all-cause deaths. Patients with summed stress score (SSS) >8 had a higher incidence of either death or cardiovascular events. Event-free survival rates for SSS 0–3, 4–8, 9–13, and ≥14 were 0.96, 0.95, 0.82, and 0.76, respectively. Multivariate Cox regression analysis showed that significant variables were SSS, history of cerebrovascular accident, and electrocardiographic abnormality at rest.

Conclusion  

The 1-year interim summary showed that cardiovascular events were significantly higher in patients with SPECT abnormality, although hard cardiac event rate was relatively low. Targeted treatment strategy is required for asymptomatic but potentially high-risk diabetic patients.