Association between hyperglycemia at admission and microvascular obstruction in patients with ST-segment elevation myocardial infarction.

Blood glucose level at admission in ST-segment elevation myocardial infarction (STEMI) is a predictor of heart failure and mortality. A previous study showed the association between hyperglycemia and microvascular dysfunction using myocardial contrast echocardiography. Late gadolinium enhancement (LGE) cardiovascular magnetic resonance imaging (CMR) can demonstrate microvascular obstruction (MVO) as the area with hypointense core within LGE. This study was performed to investigate the association between hyperglycemia at admission and MVO using CMR in patients with STEMI. Ninety-three patients with first STEMI who were treated by percutaneous coronary intervention (PCI) were included. CMR was performed within 7 days after PCI. Venous blood was collected routinely immediately after admission for plasma glucose determination before intravenous injection of some medications. Samples were analyzed in the hospital's central laboratory. We performed LGE-CMR to assess the presence of MVO. MVO was found in 34 (37%) of all 93 patients; their glucose level at admission was significantly higher than that of patients who did not exhibit MVO [204 (153-267)mg/dl vs. 157 (127-200)mg/dl, p=0.002]. There were no differences in glycosylated hemoglobin and incidence of diabetes mellitus between the two groups. A multivariable logistic regression analysis showed that glucose level at admission was an independent predictor of MVO (odds ratio, 1.014; 95% confidence interval, 1.004 to 1.023; p=0.006). The glucose level at admission 190mg/dl was the best threshold value for identifying MVO. The occurrence of MVO was significantly higher in the patients with glucose level at admission ≧190mg/dl compared with the patients with glucose level <190mg/dl [18 (53%) vs. 16 (27%), p=0.023]. Hyperglycemia at admission in STEMI patients who were treated by PCI was associated with the presence of MVO assessed by LGE-CMR.