Heart failure (HF)

- History of CHF on individually optimized treatment with HF medications unless contraindicated or not tolerated, for at least 12 weeks prior to index hospitalization and in accordance with international guidelines.
- Subjects admitted to the hospital with a primary diagnosis of decompensated HF including symptoms and signs of fluid overload requiring IV diuretic therapy in the Emergency room (ER) or any time between day 1-3 of hospital admission (index hospitalization).
- Subjects on an average/usual total daily dose of loop diuretic ≥ 40 mg of furosemide or equivalent, within 4 weeks prior to index hospitalization.
- At least one of the following 5 parameters any day between 3-7 of index hospitalization (screening period)
 -- Natriuretic peptides Brain natriuretic peptide/N-terminal prohormone of brain natriuretic peptide (BNP/NT-proBNP):
 --- Drop in BNP or NT-proBNP ≤ 30% from admission values (if measured during index hospitalization) or
 --- BNP ≥ 500 pg/ml or NT-proBNP ≥ 1800 pg/ml at screening (day 3 to 7 of index hospitalization)
 -- Body weight (BW) loss <0.4 kg per 40 mg furosemide at day 4 of index hospitalization
 -- Composite congestion score (CCS) ≥ 3
 -- Hypervolemic hyponatremia defined as serum sodium < 136 mmol/l
 -- In hospital worsening renal function defined as increased serum creatinine ≥ 0.3 mg/dl compared to index hospitalization admission values AND at least one the following
 --- Jugular venous pressure (JVP) ≥ 10 cm on physical examination
 --- Inferior vena cava (IVC) diameter > 21 mm
 --- IVC collapse with sniff < 50%
 --- At least 2+ peripheral edema or pulmonary edema or pleural effusion on chest X-ray or clinical exam

- Active or history of acute inflammatory heart disease, within 3 months prior to screening, e.g., acute myocarditis
- Acute coronary syndrome, including unstable angina, Non-ST segment elevation myocardial infarction (NSTEMI) or ST segment elevation myocardial infarction (STEMI), or major Cardiovascular (CV) surgery including coronary artery bypass graft (CABG), percutaneous coronary intervention (PCI) within 3 months prior to screening
- Any primary cause of HF scheduled for surgery or interventional therapy (e.g., TAVI), e.g., valve disease such as severe aortic stenosis or mitral valve regurgitation
- Requirement of mechanical support (intra-aortic balloon pump, endotracheal intubation, mechanical ventilation, or any ventricular assist device) or ultrafiltration/hemodialysis
- Estimated glomerular filtration rate of < 30 ml/min/1.73 m*2 determined by the Modified Diet and Renal Disease equation at screening; reassessments allowed as clinically needed
- Serum potassium ≥ 5.5 mmol/L or ≤ 3.3 mmol/L at screening; reassessments
allowed as clinically needed
- Serum sodium ≥ 146 mmol/L or ≤ 130 mmol/L at screening; reassessments allowed as clinically needed
- Concomitant treatment with potassium-sparing diuretic (with the exception of mineralocorticoid- receptor antagonist (MRA) that cannot be stopped prior to randomization and for the duration of the treatment period.