Diabetes mellitus is associated with insufficient microvascular reperfusion following revascularization for anterior acute myocardial infarction

Objective. The purpose of this study was to test the hypothesis that lack of microvascular reperfusion following revascularization might be associated with a poor clinical outcome in diabetic patients with acute myocardial infarction (AMI). Methods. We studied 134 patients with a first anterior AMI who underwent successful revascularization within 6 hours. We assessed microvascular reperfusion by using electrocardiogram recordings just before revascularization and on return to the coronary care unit. Lack of microvascular reperfusion was defined as the absence of decrease of ≥20% in the sum of ST segment elevation (ΣST). Results. Twenty-four patients had diabetes and 110 patients did not. ΣST before revascularization was similar between diabetic and nondiabetic patients. After revascularization, reduction of ΣST was significantly smaller (1.3±8.4 mm vs 6.5±10.8 mm, p=0.03), and lack of microvascular reperfusion was significantly more frequent (62.5% vs 33.6%, p=0.01) in diabetic patients. A multivariate analysis showed that diabetes was associated with insufficient microvascular reperfusion (odds ratio 3.18, p=0.03). Major adverse cardiac events occurred more frequently in patients with a lack of microvascular reperfusion (30.8% vs 15.9%, p=0.04). Conclusion. These findings suggest that lack of microvascular reperfusion following revascularization may be one of the mechanisms of a poor clinical outcome in diabetic patients with AMI.