Effect of Tolvaptan Management on Outcomes in Patients with Decompensated Heart Failure and Hyponatremia

To examine outcomes in patients with decompensated heart failure, volume overload, and hyponatremia who received standard in-hospital management vs. treatment with a vasopressin receptor antagonist, the authors of “Clinical Course of Patients with Hyponatremia and Decompensated Systolic Heart Failure and the Effect of Vasopressin Receptor Antagonism with Tolvaptan,” published in the Journal of Cardiac Failure, evaluated medical records from the Efficacy of Vasopressin Antagonism in Heart Failure Outcome Study With Tolvaptan database.

To assess “the short-term clinical course of patients hospitalized with heart failure and hyponatremia and the effect of tolvaptan on outcomes,” researchers examined the records of 232 patients with hyponatremia (defined for this study as serum sodium <135 mEq/L) from the trial’s placebo group and 1,785 non-hyponatremic patients (also from the placebo group). They found that the hyponatremic patients “had less relief of dyspnea despite receiving higher doses of diuretics (59.2% vs 69.2% improved; P < .01) and worse long-term outcomes.”

When the researchers looked at the records of 475 hyponatremic patients (including those from the placebo group and those who received treatment with the vasopressin receptor antagonist tolvaptan), they found that treatment with tolvaptan “was associated with greater likelihood of normalization of serum sodium than placebo (58% vs 20% and 64% vs 29% for day 1 and discharge, respectively; P < .001 for both comparisons), greater weight reduction at day 1 and discharge (0.7 kg and 0.8 kg differences, respectively; P < .001 and P = .008), and greater relief of dyspnea (P = .03).”

They reported that treatment with tolvaptan had no effect on long-term outcomes compared with placebo. Patients with severe hyponatremia (defined as serum sodium <130 mEq/L) who were treated with tolvaptan experienced reduced cardiovascular morbidity and mortality after discharge.

Based on these results, the authors concluded, “In patients with decompensated heart failure and hyponatremia, standard therapy is associated with less weight loss and dyspnea relief, and unfavorable longer-term outcomes compared to those with normonatremia. Tolvaptan is associated with more favorable in-hospital effects and, possibly, long-term outcomes in patients with severe hyponatremia.”