Effects of tolvaptan, a vasopressin antagonist, in patients hospitalized with worsening heart failure: a randomized controlled trial.

Context Nearly 1 million hospitalizations for chronic heart failure occur yearly in the United States, with most related to worsening systemic congestion. Diuretic use, the mainstay therapy for congestion, is associated with electrolyte abnormalities and worsening renal function. In contrast to diuretics, the vasopressin antagonist tolvaptan may increase net volume loss in heart failure without adversely affecting electrolytes and renal function. Objective To evaluate the short- and intermediate-term effects of tolvaptan in patients hospitalized with heart failure. Design, Setting, and Participants Randomized, double-blind, placebocontrolled, parallel-group, dose-ranging, phase 2 trial conducted at 45 centers in the United States and Argentina and enrolling 319 patients with left ventricular ejection fraction of less than 40% and hospitalized for heart failure with persistent signs and symptoms of systemic congestion despite standard therapy.