Immediate and short-term use of tolvaptan for acute decompensated heart failure.

luid removal is an important component of heart failure treatment to relieve signs and symptoms of edema and to improve oxygenation. In this regard, diuretic therapy should be initiated without delay, and indeed early intervention has been associated with better outcomes for patients hospitalized with acute decompensated heart failure (ADHF).1,2 Loop diuretics have a high natriuretic potency by blocking the luminal Na-K-2Cl transporter in the thick ascending limb of the loop of Henle, and they remain the first-line treatment for ameliorating symptoms in the management of ADHF.2,3 At the same time, diuretic treatment can cause worsening renal function (WRF) or acute kidney injury (AKI), and may contribute to increased length of stay, increased readmission rate and decreased shortand long-term survival. The Evaluation Study of Congestive Heart Failure and Pulmonary Artery Catheterization Effectiveness (ESCAPE) trial showed a strict correlation between diuretic dose and 6-month mortality, with higher doses failing to produce greater reductions in body weight in 395 hospitalized HF patients.4 The ESCAPE investigators revealed that diuretic dose predicted mortality even after adjustment for multiple confounders. However, we should pay close attention to the fact that the median furosemide equivalent maximal daily dose in this population was 400 mg/day to achieve the median weight loss of 2.8 kg, and that dose-dependent worsening of 6-month mortality does not seem to be observed in patients who receive a maximal in-hospital diuretic dose less than 200 mg/day (Figure 1).5 Considering the fact that the maximal in-hospital diuretic dose in Japan is gerenally lower than 200 mg/day, we should recognize that causal interrelations between the dose of loop diuretics and clinical outcomes in populations of Japanese patients warrants further investigation.