Managing patients with cardiorenal syndrome: time to look to the gut?

Oral sodium and potassium binders in heart failure

Significant improvements in the morbidity and mortality associated with chronic heart failure have been gained with the use ACE inhibitors, angiotensin receptor blockers, mineralocorticoid receptor antagonists, and diuretics. However, the use of these agents is often limited by their propensity to precipitate worsening renal function and hyperkalemia, particularly in patients with chronic kidney disease. Several pharmacologic agents have been developed in recent years that utilize the gastrointestinal tract as an alternate route for drug absorption, electrolyte exchange, and drug and electrolyte elimination. The existing data establishing the safety and efficacy of these novel agents will be the focus of this review.

Decongestion in acute heart failure

Congestion is a major reason for hospitalization in acute heart failure (HF). Therapeutic strategies to manage congestion include diuretics, vasodilators, ultrafiltration, vasopressin antagonists, mineralocorticoid receptor antagonists, and potentially also novel therapies such as gut sequesterants and serelaxin. Uncertainty exists with respect to the appropriate decongestion strategy for an individual patient. In this review, we summarize the benefit and risk profiles for these decongestion strategies and provide guidance on selecting an appropriate approach for different patients. An evidence-based initial approach to congestion management involves high-dose i.v. diuretics with addition of vasodilators for dyspnoea relief if blood pressure allows. To enhance diuresis or overcome diuretic resistance, options include dual nephron blockade with thiazide diuretics or natriuretic doses of mineralocorticoid receptor antagonists. Vasopressin antagonists may improve aquaresis and relieve dyspnoea. If diuretic strategies are unsuccessful, then ultrafiltration may be considered. Ultrafiltration should be used with caution in the setting of worsening renal function. This review is based on discussions among scientists, clinical trialists, and regulatory representatives at the 9th Global Cardio Vascular Clinical Trialists Forum in Paris, France, from 30 November to 1 December 2012.