Coronary blood flow, myocardial oxygen consumption, and myocardial metabolism in normal and hyperthyroid human subjects.

Abstract

The effects of thyroid hormone excess on myocardial hemodynamics and carbohydrate metabolism were determined in a group of subjects, and the findings compared with those obtained in a group of normal individuals. The results indicate that in thyrotoxicosis there tends to be an increase in coronary blood flow and myocardial oxygen consumption and a normal per cent extraction of oxygen by the myocardium. The metabolism of glucose, lactic acid, and pyruvic acid was virtually identical in the 2 groups. No relationship was demonstrable between the arterial levels of the carbohydrate substances and their extraction by the heart.