Combination of myocardial perfusion imaging, left ventricle function parameters and coronary artery calcium score in risk evaluation in patients with diabetes mellitus.

Objective: Myocardial perfusion imaging (MPI) can be challenging in some cases of multi vessel involvement. Our aim was to examine specific group of patients with diabetes mellitus (DM), who did not have significant reversible ischaemia diagnosed on perfusion study itself, and asses additional value of functional parameters obtained from gated acquisition and added information from coronary artery calcium score (CACS).

Subjects and methods: One hundred and seventy eight patients with a history of DM, with summed difference score (SDS)≤1, were included in the study. All patients underwent gated acquisition with recording of functional parameters and CACS evaluation. During the follow-up, cardiac events (CE) were recorded.

Results: During the median follow-up of 20.3 months there were 23 CE encountered. Optimal cut-off value for CACS to predict CE was found at 1427, higher values were significantly related to CE (P<0.001). Low stress left ventricular ejection fraction (LVEF) <45% and induced stress LVEF drop for 5% were also more frequent in CE group (P=0.001, P=0.008). Multivariable Cox analysis revealed low stress LVEF (P=0.001, HR=4.48, 95%CI 1.79-11.22), stress induced LVEF drop (P=0.017, HR 3.13, 95%CI 1.22-8.01) and high CACS (P<0.001, HR 10.52, 95%CI 4.32-25.63) as significant predictors of CE.

Conclusion: Low stress LVEF under 45%, post-stress LVEF drop for more than 5% and CACS more than or equal to 1427 are significant predictors of CE in patients with DM, who did not have reversible ischemia detected on MPI single photon emission computed tomography (SPECT).