Combination Oral Acetazolamide and Intravenous Furosemide on Acute Decompensated Heart Failure Outcomes

Inclusion Criteria: * Agree to be included in the research by signing informed consent * Patients with a clinical diagnosis of acute decompensated heart failure with at least one clinical sign of volume overload with a congestion score ≥2 (ADVOR Score) (e.g. edema (score 2 or more), ascites confirmed by physical examination or ultrasonography or pleural effusion confirmed by chest x-ray or echocardiography). * Patients on routine oral loop diuretic therapy with a dose of ≥40 mg furosemide for ≥1 month * Plasma NT-proBNP levels that increase ≥300 pg/mL or the applicable cut-off according to the age range at the time of examination in the ER. Exclusion Criteria: * Subjects with acute coronary syndrome * History of congenital heart disease requiring surgical correction. * Subjects in cardiogenic shock. * Estimated glomerular filtration rate \<20 mL/min/1.73m² at the time of examination. * Use of renal replacement therapy or ultrafiltration at any time before the study was included. * Treatment with acetazolamide within 1 month before randomization. * Exposure to nephrotoxic agents (i.e. contrast dye) is anticipated within the next 3 days * Subjects who are pregnant or breastfeeding. * Subjects with urinary incontinence who are unwilling to use a bladder catheter.