3. Antidiuretic Hormone in Congestive Heart Failure

Abstract

In the present series of patients, no consistent correlations were observed between the plasma ADH level and the severity of congestive heart failure or the stadium of decompensation. However, a positive correlation was observed between the plasma ADH level and the venous pressure. A positive correlation was also observed between the serum osmolality and the venous pressure. There seemed to be a positive correlation between the plasma ADH level and the serum osmolality, and this correlation was remarkable in the course of a patient. The plasma ADH activity after over 14 hours' deprivation of water was usually within the normal limit in patients with congestive heart failure examined in the present study. High levels were observed, however, under certain conditions. There were no consistent data which indicated the impaired osmoreceptor function. The serum osmolality after water deprivation was within normal limits and the decrease in serum osmolality after hydration was accompanied by an inhibition of plasma ADH activity in most cases. Although there was no hyponatremic case in this series, it might be presumed that in some cases of hyponatremia, except for the cases in which the homeostasis mechanism is extremely exhausted, the regulation to maintain the circulating blood volume predominates over the regulation of osmolality. The venous pressure is set at a higher level by cardiac decompensation. An elevation in venous pressure leads to an increase in extravasation of body fluid and a decrease in venous return with an increased oncotic pressure of the venous blood. These changes in body fluid stimulate the release of ADH, which leads to hypervolemia and elevation in venous pressure, thus constituting a vicious circle. Even in this case the ADH seems to act homeostatically together with mineral corticoids in adjusting to the high venous pressure set by cardiac failure. In conclusion, the ADH system seems to play a role in homeostasis of the body fluid in congestive heart failure. The mode of action seems to be a physiological one even in cases with congestive heart failure in the present study. And the action of the ADH is thought to have some-thing to do not only with mineralocorticoids but also with cortisol.