Ultrafiltration therapy for cardiorenal syndrome: physiologic basis and contemporary options.

BACKGROUND: Heart failure (HF) has a high readmission rate in part due to conventional and recently developed therapeutic options having suboptimal results. Extracorporeal and peritoneal ultrafiltration have been advocated as more beneficial methods for fluid removal in decompensated or refractory HF, respectively.

METHODS: Traditional and emerging concepts explaining the pathophysiology of HF and the cardiorenal syndrome are reviewed. Extracorporeal and peritoneal ultrafiltration clinical trials are then discussed in terms of potential physiologic benefits, feasibility and their effects on both cardiac and renal function.

RESULTS: Ultrafiltration therapy can efficiently correct volume overload in the acute setting, improve cardiac functional and quality of life parameters, and is associated with long-lasting benefits such as reduced HF-related readmissions. Although excessive fluid removal can adversely affect the kidneys, there is evidence that careful protocols can restore diuretic sensitivity and maintain stable renal function; crafting safe parameters has yet to be studied.

CONCLUSION: While extracorporeal ultrafiltration is an appealing therapeutic option for patients with acute decompensated HF, determining the optimal fluid removal rate and the impact on renal function need further investigation. Peritoneal dialysis may be an appropriate alternative in the setting of chronic refractory HF, but controlled studies are needed. Further trials are warranted to determine the long-term outcomes from both ultrafiltration modalities in HF.