Urinary Chloride and Sodium Changes and Residual Congestion in Acute Heart Failure

The goal of this observational study is to learn how changes in urinary sodium and chloride levels relate to fluid overload and short-term outcomes in patients hospitalized with acute heart failure (AHF). The main questions it aims to answer are: * Do changes over time in urinary sodium and chloride reflect how well excess fluid is being removed during hospitalization? * Are these changes associated with residual congestion at discharge and with the risk of worsening heart failure or death after discharge? Participants hospitalized for AHF and treated with intravenous diuretics as part of their usual care will have clinical assessments, blood and urine tests, and echocardiographic evaluations collected at several time points during their hospital stay. Researchers will also record clinical outcomes, including worsening heart failure or death, at 30 days and 3 months after discharge.

NCT Number	NCT07597512
Lead Sponsor	Fundacion para la Investigacion Biomedica del Hospital Universitario Ramon y Cajal Collaborators: Carlos III Health Institute
Conditions	Acute Heart Failure (AHF), Heart Failure, Congestion
Enrollment	223 participants
Start Date	2026-05
Primary Completion	2028-12-31 (estimated)
Study Completion	2028-12-31 (estimated)
Updated on ClinicalTrials.gov	2026-05-22