The Output of the Heart Per Beat in Hyperthyroidism

The Hemodynamics of Thyrotoxicosis in Man With Special Reference to Coronary Blood Flow and Myocardial Oxygen Metabolism 1

“…Blood flow through the extremities was assumed to be increased in thyrotoxicosis because of the high rate of heat elimination when the hand was placed in a calorimeter (1). Several workers found an increase in cardiac output in thyrotoxic subjects using the oxygen content of arm vein blood in the Fick formula (2)(3)(4). Similar findings were obtained using the nitrous oxide (5) and acetylene methods (6,7).…”

“…2Wisconsin Heart Association Research Fellow. 3 Heart Trainee of the National Heart Institute, U. S. Public Health Service, 1955. rabbit auricle (12). Dock and Lewis established that thyroid feeding to rats increased the total body oxygen consumption (13).…”

Blood Volume in Hyperthyroidism.

“…More recently the cardiac output in hyperthyroidism has aroused a renewed interest (8) (9) (10) (11) (12). In spite of the widely different methods employed, all investigators with the single exception of Rabinowitch and Bazin (9) have come to the same conclusion as that reached by Plesch. Blumgart, Gargill and Gilligan (13) studied 13 thyrotoxic patients and showed that the speed of blood flow through the lungs was much faster than the avefage normal speed of flow.…”

Blood Flow in the Extremities of Patients With Heart Disease

“…In 136 normal persons3 the arteriovenous oxygen difference in the arm averaged 4.8 per cent by volume. There is little difference in gas content of arm and leg vein blood of normal persons at rest.4 However, the difference in arteriovenous oxygen of normal persons ranged from 2.5 to 9 per cent by volume in a series tabulated by Rabinowitch,3 indicating that it is hazardous to draw conclusions as to cardiac output from the gas content of arm vein blood. The range of normal cardiac output or of basal metabolism is only one fourth as great as the variation in blood flow of the resting limb.…”