SUMMARY
Introduction/Objective Myocardial perfusion imaging (MPI) is clinically useful for the evaluation of
coronary artery disease in patients with diabetes mellitus. However, the prevalence of ischemia and its
ability to predict future cardiac events is less clear. The aim was to determine the incidence of cardiac
events in diabetic patients and the relationship between them and MPI findings.
Methods Two cohorts of patients, 98 diabetics and 100 non-diabetics, with medium- to high-risk of
coronary artery disease without previous coronary revascularization, were studied prospectively. All of
them were outpatients who underwent 99mTc-sestamibi MPI with dipyridamole. The data about cardiac
events were collected during a follow-up period of two years.
Results Cardiac events occurred in 17.3% diabetics and in 8% non-diabetics (p = 0.048). Diabetics had
shorter estimated event-free time of 24.7 months (95% CI 23.2–26.2) versus non-diabetics’ estimated
event-free time of 28.5 months (95% CI 27.4–29.5) (p = 0.046). The independent predictors of cardiac
events were male sex (p = 0.010), previous myocardial infarction (p < 0.001), presence of the symptoms
of angina (p = 0.014), and all variables derived from MPI findings. After adjustment for variables derived
from MPI findings, the significant predictors in diabetics were the size of stress perfusion defect (p = 0.022),
summed stress score (p = 0.011), and summed difference score (p = 0.044).
Conclusion In diabetic patients, the cumulative rate of cardiac events was higher and the event-free
survival was worse. MPI could help in prediction of cardiac events in diabetics and the most important
predictors were size of stress perfusion defect, summed stress score, and summed difference score.
