Review Myocardial Glucose Metabolism Overview

Life critically depends on the beating of the heart, an energy-consuming process fueled by hydrolysis of adenosine triphosphate (ATP) to adenosine diphosphate (ADP). In fact, the heart is the organ with the highest specific oxygen consumption, reflecting its intense, mostly aerobic, metabolic activity. The most impor-tant substrates for energy production in the normal myocardium are fatty acids, glucose and lactate, in decreasing order of impor-tance. Together, anaerobic and aerobic metabolism of these sub-strates account for almost all of energy production in the normal adult heart, the respective contribution of each depending on the metabolic and hormonal status.1 Catabolic breakdown of glu-cose occurs in two stages: glycolysis, an anaerobic, cytoplasmic stage with low ATP yield (2 ATP/glucose), followed by aerobic oxidation of glycolysis-derived pyruvate in the mitochondria. Pyruvate is first converted to acetyl-CoA by the action of pyru