• No possibility to collect reliable urine spot samples after diuretic administration
  • Administration of any diuretic within 6 h before randomisation, except for a mineralocorticoid receptor antagonist (MRA) or sodium‑glucose co‑transporter 2 (SGLT2) inhibitor as part of the patient’s maintenance treatment for heart failure. Patients can still be included in the DECONGEST study after withholding these diuretics for 6 h, after which randomisation can be performed if they qualify all other criteria.
  • Severe kidney dysfunction, defined as an estimated glomerular filtration rate (eGFR) <15 mL/min/1.73m² calculated by the Chronic Kidney Disease Epidemiology Collaboration (CKD‑EPI) formulaat randomisation, and/or previous, current, or planned future renal replacement therapy
  • Systolic blood pressure <90 mmHg, mean arterial pressure <65 mmHg, or need for inotropes/vasopressor therapy at randomisation
  • Any acute coronary syndrome within 30 days prior to enrolment, defined as typical chest pain with a troponin rise above the 99th percentile of normal and/or electrocardiographic changes suggestive of cardiac ischemia
  • History of heart or kidney transplantation
  • History of mechanical circulatory support
  • Known obstructive hypertrophic cardiomyopathy, congenital heart disease, acute mechanical cause of AHF (e.g., papillary muscular rupture), acute myocarditis, or constrictive pericarditis according to the treating physician
  • Pregnant or breastfeeding woman
  • Concomitant participation in another interventional study
  • At least 18 y/o and able to provide informed consent
  • Hospital admission (anticipated stay >24 h after randomisation) with diagnosis of acute heart failure according to the treating physician
  • At least one of the following three signs of volume overload:
    • bilateral oedema 2+, indicating clear pitting
    • ascites that is amenable for drainage, confirmed by echography
    • uni- or bilateral pleural effusions that are amenable for drainage, confirmed by chest X-ray or lung ultrasound
  • Plasma N-terminal of the pro‑hormone of B‑type natriuretic peptide (NTproBNP) level >1,000 ng/L