Tolvaptan for Advanced or Refractory Heart Failure

Inclusion Criteria: * Hospital admission for ADHF with volume overload as evidenced by ≥ 2 of the following: Elevated JVP, peripheral edema, ascites, pulmonary rales, congestion on chest X-ray, elevated NT-pro-BNP \> 2000 pg/ml * Inadequate clinical response indicated by body weight loss \< 1.0 kg/day over 48 hours despite adequate doses of IV loop diuretic (at least 40 mg furosemide daily) and fluid restriction 2 L/24 hours. * ≥1 of the following over the preceding 48 hours: Potential need for inotropic support to improve urine output, and/or renal insufficiency (estimated glomerular filtration rate \<45 mL/min/1.73 m2) * Serum sodium ≤134 mmol/L * ≥18 years-old Exclusion Criteria: * Cardiac surgery within 60 days of enrollment * Planned cardiac mechanical support or transplant; subjects with previously implanted ventricular assist device (VAD) will not be excluded * Need for intravenous pressor support for symptomatic hypotension * Biventricular pacemaker placement within the last 60 days * Hemofiltration or dialysis * Known cirrhosis * Supine systolic arterial blood pressure less than 85 mmHg * Refusal or inability to sign informed consent