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 > or = 20% in the sum of ST segment elevation (sigmaST).
RESULTS: Twenty-four patients had diabetes and 110 patients did not. SigmaST before revascularization was similar between diabetic and nondiabetic patients. After revascularization, reduction of sigmaST 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.