Effects of tolvaptan on urine output in hospitalized heart failure patients with hypoalbuminemia or proteinuria

Hypoalbuminemia is an independent prognostic factor in hospitalization for heart failure (HHF). Hypoalbuminemia or proteinuria is related to resistance to loop diuretics. Tolvaptan is an oral non-peptide, competitive antagonist of vasopressin receptor-2. It has been used for the treatment of volume overload in HHF patients in several Asian countries. Several studies have demonstrated marked improvement in congestion in HHF patients. However, whether tolvaptan is useful for HHF patients with hypoalbuminemia or proteinuria (both of which are related to resistance to loop diuretics) has not been clarified. We examined the diuretic response to tolvaptan in HHF patients with hypoalbuminemia or proteinuria. We defined hypoalbuminemia as a serum level of albumin < 2.6 g/dl. Fifty-one HHF patients who received additional tolvaptan upon therapies with loop diuretics were divided into the hypoalbuminemia group (n = 24) or control group (n = 27). The changes in urine output per day were not different between the two groups [610 (range 100–1032); 742 (505–1247) ml, P = 0.313]. There was no difference in diuretic responses between patients with and without proteinuria. The serum level of albumin did not correlate with changes in urine output per day after tolvaptan treatment (P = 0.276, r = 0.156). Thus, additional administration of tolvaptan elicited a good diuretic response in HHF patients with hypoalbuminemia or proteinuria. These data suggest that tolvaptan might be beneficial for such HHF patients.