Increased aldosterone secretion in dogs with right-sided congestive heart failure and in dogs with thoracic inferior vena cava constriction.

Studies (1-5) of patients with congestive heart failure, decompensated hepatic cirrhosis and nephrosis have provided evidence of increased amounts of aldosterone or aldosterone-like substances in urine during edema or ascites formation. More recently, it has been demonstrated (6) that increased urinary excretion of aldosterone occurs in association with sodium retention in dogs with right heart failure and in dogs with ascites secondary to constriction of the thoracic inferior vena cava. The data in both man and dog imply that the blood level of aldosterone is elevated. Numerous attempts have been made to elucidate the mechanism regulating aldosterone secretion in clinical states associated with the formation of edema, but no data have been reported to show that increased circulating aldosterone results from increased secretion rather than from a decreased rate of inactivation. The purpose of this study was to determine the relative rates of secretion of aldosterone in 1) dogs with cardiac failure produced by stenosis of the pulmonary artery, 2) dogs with thoracic inferior vena cava constriction and ascites, and 3) normal dogs.