The objective of this study is to prospectively compare decongestive therapy administered by the Reprieve DMS system to Optimal Diuretic Therapy (ODT) in the treatment of patients diagnosed with acute decompensated heart failure (ADHF). The main objective is to determine if the Reprieve DMS is non-inferior to state-of-the-art urine sodium guided aggressive diuretic titration in two European HF centers of excellence.

Inclusion Criteria:

1. Hospitalized with a diagnosis of heart failure as defined by the presence of at least 1 symptom AND 1 sign.
2. ≥10 pounds (4.5 kg) above dry weight either by historical weights or as estimated by health care provider.
3. Prior use of loop diuretics within 30 says prior to admission.
4. ≥ 18 years of age able to provide informed consent and comply with study procedures.

Exclusion Criteria:

1. Inability to place Foley catheter or IV catheter.
2. Hemodynamic instability.
3. Dyspnea due primarily to non-cardiac causes.
4. Acute infection with evidence of systemic involvement.
5. Estimated glomerular filtration rate (eGFR) < 20 ml/min/1.73m2 calculated using the MDRD equation or current use of renal replacement therapy.
6. Significant left ventricular outflow obstruction, uncorrected complex congenital heart disease, severe stenotic valvular disease, infiltrative or constrictive cardiomyopathy, acute myocarditis, type 1 acute myocardial infarction requiring treatment, or any other pathology that, in the opinion of the investigator, would make aggressive diuresis poorly tolerated.
7. Inability to follow instructions or comply with follow-up procedures.
8. Other concomitant disease or condition that investigator deems unsuitable for the study, including drug or alcohol abuse or psychiatric, behavioral or cognitive disorders, sufficient to interfere with the patient's ability to understand and comply with the study instructions or follow-up procedures.
9. Severe electrolyte abnormalities.
10. Presence of active coronavirus disease 2019 (COVID-19) infection.
11. Enrollment in another interventional trial during the index hospitalization.
12. Inability to return for follow-up study visits.
13. Life expectancy less than 3 months.
14. Women who are pregnant or intend to become pregnant.