Enhancement of left ventricular function by glucose-insulin-potassium infusion in acute myocardial infarction

Twenty-eight patients admitted to the hospital with suspected acute myocardial infarction underwent baseline studies within 12 hours of onset of symptoms. Patients were then randomized to receive control infusion (0.45 percent sodium chloride at 20 ml/hour) (15 patients) or glucoseinsulin-potassium infusion (300 g glucose, 50 units regular insulin, 80 mEq KCl/liter water at 1.5 ml/kg per hour) (13 patients) for 48 hours. All patients received 0.45 percent sodium chloride for 2 more days. Coronary arteriograms and left ventriculograms were obtained in 26 (93 percent) of 28 patients 2 to 3 weeks after infarction.Radionuclide ejection fraction improved during glucose-insulin-potassium infusion (49 ± 4 to 55 ± 5 percent, p < 0.01). Before discharge, the angiographic ejection fraction was greater in the glucose-insulin-potassium recipients than in control patients (43 ± 3 versus 35 ± 3 percent, p < 0.05). Radionuclide ejection fraction decreased in all control patients during the study (42 ± 4 to 37 ± 3 percent, p < 0.0005) and did not change significantly in the treated group (49 ± 4 to 43 ± 5 percent, p = not significant [NS] by paired t test). Regional wall motion analysis revealed an increase in ejection fraction in the “infarcted zone” in the treated group only (44 ± 7 to 54 ± 8 percent, p < 0.01) during glucose-insulin-potassium infusion. There was also a significant decrease in ejection fraction in the “noninfarcted zone” in the control group only (50 ± 4 to 45 ± 4 percent, p < 0.01).During experimental infusion pulmonary arterial end-diastolic pressure decreased in the glucose-insulin-potassium group (17 ± 2 to 12 ± 2 mm Hg, p < 0.01) without changing significantly in the control group. Calculated end-diastolic and end-systolic volume indexes changed in opposite directions in the two groups during experimental infusion (end-diastolic volume index 80 ± 5 to 90 ± 9 ml/m² in the control group versus 70 ± 9 to 55 ± 6 ml/m² in the treated group, p < 0.005 for change from baseline value between groups and the end-systolic volume index 48 ± 6 to 55 ± 8 ml/m² in the control group versus 39 ± 8 to 26 ± 5 ml/m² in the treated group (p < 0.01 for change from baseline value between groups).These data suggest that glucose-insulin-potassium infusion after acute myocardial infarction in human beings (1) increases global ejection fraction, (2) Increases ejection fraction in the “infarcted zone” without changing ejection fraction in the “noninfarcted zone”, and (3) decreases pulmonary arterial end-diastolic pressure and end-diastolic and end-systolic volumes.