Glucose-Insulin-Potassium Administration in Acute Myocardial Infarction

Physiologic studies spanning fifty years suggest that glucose and insulin can be beneficial to cardiac performance under experimental conditions. In 1926, Visscher & Muller observed the positive inotropic effects of insulin on the isolated beating turtle heart (I). Bayliss et al (2) described in 1928 the action of insulin and sugar on the heart-lung preparation. The marked abnormality in carbohydrate metabolism attending fatal diphtheritic myo­ carditis was reported to respond to dextrose and insulin administration in 1930 (3). In his pioneering studies on coronary blood flow and myocardial metabolism, Bing identified extraction and utilization of glucose, lactate, pyruvate, fatty acids, and ketone bodies (4, 5). In experiments on glucose uptake by the perfused rat heart, Morgan and associates (6) found that anoxia increased glucose uptake, and anoxia plus insulin further accelerated glucose uptake. Brachfe1d & Scheuer (7) ob­ served that myocardial ischemia accelerated glycolysis as evidenced by in­ creased glucose consumption and lactate production. Scheuer & Stezoski (8) demonstrated that elevations in cardiac glycogen increased glycolytic reserve and improved resistance to hypoxia mainly by enhancing glycolytic and anaerobic ATP production.