Effect of modified glucose-insulin-potassium on free fatty acids, matrix metalloproteinase, and myoglobin in ST-elevation myocardial infarction.

Insulin has a free fatty acid (FFA)-suppressive effect, vascular endothelial growth factor (VEGF)- and matrix metalloproteinase (MMP)-lowering effect, and a potential myocardial-protective effect. Whether low-dose insulin exerts these effects in patients with acute myocardial infarction (MI) was investigated. Thirty-two patients administered thrombolytics and heparin were randomly assigned to a modified glucose-insulin-potassium (GIK) regimen (insulin 2.5 U/hour, dextrose and potassium titrated to prevent hyperglycemia) or normal saline solution and potassium (controls) for 48 hours. Plasma FFA, serum VEGF, pro-MMP-1, and myoglobin were measured at baseline and sequentially for 48 hours. FFA concentrations were increased at baseline; increased further in the first 4 hours in controls (p