Acute-Phase Glucose Fluctuation Is Negatively Correlated With Myocardial Salvage After Acute Myocardial Infarction - Involvement of Monocyte Subsets

Background: It remains unclear whether glycemic fluctuation immediately after acute myocardial infarction (AMI) can affect myocardial damage. This study investigated the impact of glucose fluctuation on myocardial salvage following successful recanalization of primary AMI. Methods and Results: A total of 36 consecutive patients with AMI were studied. Glycemic variability, as indicated by the mean amplitude of glycemic excursion (MAGE), was measured on a continuous glucose monitoring system. Three subsets (CD14(+)CD16(-), CD14(++)CD16(+) and CD14(+-)CD16(+)) were measured on flow cytometry 1, 2, 3, 4 and 5 days after AMI onset. A 2-h oral glucose test was performed in 23 patients who had no previous diagnosis of diabetes and/or glycated hemoglobin <6.5%, after the onset of AMI at 2 weeks. Plasma active glucagon-like peptide (GLP)-1 level was measured in each sample. The extent of myocardial salvage 7 days after AMI was evaluated on cardiovascular magnetic resonance imaging. MAGE and the peak CD14(+)CD16- monocyte level were significantly negatively correlated with myocardial salvage index (MSI). MAGE was significantly correlated with peak CD14(+)CD16(-) monocyte level. Of interest, plasma GLP-1 level was significantly positively correlated with MSI and significantly negatively correlated with MAGE. Conclusions: Glucose fluctuations during the acute phase of AMI affect MSI, indicating that manipulation of glucose variability from peak to nadir might be a potential therapeutic target for salvaging ischemic damage.