Pathogenesis of Congestive Heart Failure

Abstract

Metabolic studies and electrolyte studies of the plasma in patients in congestive heart failure have suggested that certain changes occur in the cells which might be responsible for the ultimate accumulation of salt and water. The effects of posture and exercise on plasma volume and plasma constituents were studied in mild cardiac patients by following serial changes in the plasma radio-iodinated serum albumin, hematocrit, and plasma osmol and Na concentrations. When patients were made to change position from recumbent to standing position the plasma volume decreased and the hematocrit increased but the plasma osmol and Na concentrations remained the same. No change in plasma volume occurred when patients were made to stand in deep water. These observations were interpreted to indicate transudation of plasma ultrafiltrate from the capillaries into the interstitial spaces because of increased hydrostatic intracapillary pressure. When patients were made to exercise lightly on the treadmill or on the 2-step platform the plasma volume decreased and the hematocrit, osmol and Na concentrations increased. Virtually no change occurred in the total plasma osmol or Na content. It was felt that circulatory stress of exercise would cause an increase in osmotic pressure of the cells resulting in migration of water from the plasma compartment into the cells. These changes were considered to initiate active renal retention of salt and water in the pathogenesis of congestive heart failure.