Myocardial Metabolism

Abstract

Review is presented of the metabolism of the hur an heart as studied by coronary sinus catheterization. Carb hydrates supply about 30-40% of the total oxidative requirements of the heart; fats, ketone bodies and amino acids supply the remainder. Fatty acids can be stored by heart muscle. In ischemia of heart muscle as produced by hemorrhagic shock or by artificial embolization of coronary arteries, there is inhibition of the co-enzyme cocarboxylase, resulting in increased concentration of pyruvate in coronary vein blood. When ischemia and myocardial anoxia are more severe, anerobiasis of the heart muscle appears as shown by increased concentration of lactate in coronary vein blood. No metabolic alterations in myocardial metabolism are found in congestive failure, illustrating that the disturbance lies not in energy production but energy utilization.