The effects of glucose on myocardial substrate utilization in acute myocardial infarction or angina pectoris

Infusion of glucose-insulin-potassium during acute myocardial infarction has favorable clinical and hemodynamic effects, presumably as a result of decreased myocardial utilization of free fatty acids. In 14 patients with coronary artery disease, hypertonic glucose (a bolus of 10 g followed by infusion of a 30% glucose solution at a constant rate of 10 mg/ kg/min) was infused and arterial and coronary sinus levels of glucose, lactate and free fatty acids were measured before and after 15 and 30 minutes of infusion. Arterial glucose and lactate levels increased significantly after glucose infusion, whereas free fatty acid levels decreased significantly. Modest but significant correlations also existed between glucose arterial levels and the arterial-coronary sinus glucose difference (r = 0.53, p < 0.001); arterial lactate and the arterial-coronary sinus lactate difference (r = 0.35, p < 0.01); arterial free fatty acids; and the arterial-coronary sinus free fatty acid difference (r = 0.62, p < 0.001). These results with a hypertonic glucose infusion are similar to those reported after infusion of glucose-insulin-potassium without the potential for harmful adverse effects from infusions of insulin or potassium. Therefore, infusion of hypertonic glucose may be beneficial in patients with coronary artery disease. Further work is necessary to study its effects in different subgroups of patients with coronary artery disease.