Oral Sodium to Preserve Renal EfficiencY in Acute Heart Failure

Inclusion Criteria: * Age ≥ 18 years old AND * Admitted to cardiology floor (non-ICU) with primary diagnosis of decompensated heart failure AND * NT-proBNP \>1000 ng/L AND * Initiation of continuous furosemide infusion at a rate of 10 mg/hr or higher Exclusion Criteria: * Serum sodium (Na+) level less than 120 or greater than 145. * Average Systolic Blood Pressure \>180 mmHg or Diastolic Blood Pressure \>100 mmHg over past 24 hours. * Anticipated length of stay less than 72 hours. * Use of vasopressin antagonist * Current use of sodium chloride tablets * Active diagnosis of diabetes insipidus * Inability to tolerate oral diet or swallow pills * Presence of malabsorptive gastrointestinal disorder (Crohn's disease, short gut syndrome) * The use of iodinated radiocontrast material in the past 72 hours or anticipated use of intravenous contrast during the current hospitalization * Admission with intention to transplant or implant permanent Ventricular Assistive Device * Use of intravenous inotropes, vasopressors or vasodilators at enrollment * A baseline estimated glomerular filtration rate \<15 mL/min/1.73m² according to the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formula at the moment of inclusion * Use of renal replacement therapy at time of enrollment