Tolvaptan add-on Therapy to Overcome Loop Diuretic Resistance in Acute Heart Failure With Renal Dysfunction

This is a single-center, open-label, randomized controlled trial, which will enroll 128 patients hospitalized due to AHF. These patients with wet-warm phenotype whose estimated glomerular filtration rates at admission are above 15 and below 60 mL/min/1.73 m2, and cumulative urine output \<300 mL in 2 hours after the first dose of intravenous furosemide will be randomly assigned 1:1 to receive a standard care with uptitrating intravenous furosemide alone or a combination therapy with tolvaptan 15mg once daily for 2 days. The standard furosemide treatment will follow the modified 2019 Position Statement from the ESC Heart Failure Association. The primary endpoint is the cumulative urine output at 48 hour. Key secondary endpoints include the improvement of fractional excretion of sodium at 6 hour, the total dose of furosemide, the changes in the body weights, the net fluid loss, the lessening of diastolic dysfunction parameters on echocardiography, and the incidence of clinically relevant worsening renal function at 48 hour.