Can a Vasopressin Receptor Antagonist Prevent Worsening of Heart Failure?

Rehospitalization rates for worsening congestive symptoms of heart failure (HF) can reach 50% at 6 months, despite diuretic use. Elevated arginine vasopressin (AVP) levels in HF patients might contribute to vasoconstriction, water retention, and hyponatremia. AVP antagonists, especially those with affinity for the renal vasopressin (V₂) receptor, have shown promise for limiting congestion and hyponatremia.

In a multicenter, double-blind, phase 2 trial, 319 hospitalized HF patients were randomized to receive either the oral vasopressin antagonist tolvaptan (at 30, 60, or 90 mg) or placebo once daily, plus standard therapy. All patients had LV ejection fractions <40% and signs or symptoms of congestion despite treatment with diuretics. Patient…