Peritoneal dialysis for chronic cardiorenal syndrome: Lessons learned from ultrafiltration trials

Abstract

The current models of cardiorenal syndrome (CRS) are mainly based on a cardiocentric approach; they assume that worsening renal function is an adverse consequence of the decline in cardiac function rather than a separate and independent pathologic phenomenon. If this assumption were true, then mechanical extraction of fluid (i.e., ultrafiltration therapy) would be expected to portend positive impact on renal hemodynamics and function through improvement in cardio-circulatory physiology and reduction in neurohormonal activation. However, currently available ultrafiltration trials, whether in acute heart failure (AHF) or in CRS, have so far failed to show any improvement in renal function; they have reported no impact or even observed adverse renal outcomes in this setting. Moreover, the presence or absence of renal dysfunction seems to affect the overall safety and efficacy of ultrafiltration therapy in AHF. This manuscript briefly reviews cardiorenal physiology in AHF and concludes that therapeutic options for CRS should not only target cardio-circulatory status of the patients, but they need to also have the ability of addressing the adverse homeostatic consequences of the associated decline in renal function. Peritoneal dialysis (PD) can be such an option for the chronic cases of CRS as it has been shown to provide efficient intracorporeal ultrafiltration and sodium extraction in volume overloaded patients while concurrently correcting the metabolic consequences of diminished renal function. Currently available trials on PD in heart failure have shown the safety and efficacy of this therapeutic modality for patients with chronic CRS and suggest that it could represent a pathophysiologically and conceptually relevant option in this setting.

Keywords: Cardiorenal syndrome, Peritoneal dialysis, Heart failure, Ultrafiltration

Core tip: This article briefly reviews the clinical significance of renal dysfunction in heart failure and evaluates the results of the ultrafiltration studies in acute heart failure and cardiorenal syndrome (CRS). It concludes that peritoneal dialysis could represent an efficacious option for chronic CRS due to its ability to simultaneously address renal and cardiac dysfunction in these patients. Recent technical advances such as possibility of initiating peritoneal dialysis (PD) in the acute setting and placement of the PD catheter by interventional radiology could make this home-based therapeutic option even more accessible and intriguing.