Physiologic Changes during Chronic Congestive Heart Failure in Dogs with Tricuspid Insufficiency and Pulmonic Stenosis

Abstract

Chronic congestive heart failure was studied in dogs with surgically-produced tricuspid insufficiency and pulmonic stenosis. Ascites formed in association with an elevation in mean right atrial pressure. The volume of ascitic fluid and the rate of urinary sodium excretion varied greatly in individual dogs during the course of congestive failure and among the different animals. Sodium retention was most common but periods of sodium balance and natriuresis occurred. Comparative data on the right and left ventricles were obtained from determinations of intracardiac pressures, measurements of ventricular muscle mass at the time of sacrifice and studies of the lungs for evidence of chronic passive congestion. There was significant right ventricular hypertrophy but no evidence of left ventricular hypertrophy or failure.