Peritoneal dialysis with hypertonic dextrose dialyzing solutions was used to dehydrate 15 patients in refractory congestive heart failure. The clinical improvement which was achieved following this procedure could be related largely to the degree of excess fluid removal and visceral decongestion. In these 15 patients there was an average weight loss of 5.2 kg (11.5 lb) and an average excess fluid removal of 7,285 cc. Circulation times and venous pressures fell to 50% of predialysis values, and plasma volumes were reduced in each instance. Of five patients studied, there was only one who showed a substantial increase in cardiac output; the other four patients showed no significant change. Twelve of 15 patients had restored diuretic responsiveness postdialysis. Serum electrolyte values returned toward normal in all patients studied. We have found peritoneal dialysis to be a safe, effective, and valuable ancillary tool in the management of patients with refractory congestive heart failure.