Bedside NT-proBNP Monitoring in Acute Heart Failure

Acute decompensated heart failure (ADHF) is a major cause of cardiovascular hospitalization. Although aggressive decongestive therapy is the cornerstone of ADHF management, accurately assessing the degree and speed of decongestion during hospitalization remains challenging. Residual congestion at discharge is common and is associated with adverse clinical outcomes.

Current clinical practice relies on multiple parameters, including symptoms, physical examination findings, urine output, body weight changes, renal function, and imaging findings, to evaluate decongestion. Natriuretic peptides, including NT-proBNP, are widely used for diagnosis and risk stratification in heart failure; however, the clinical significance of serial NT-proBNP changes during hospitalization under contemporary guideline-directed treatment remains incompletely understood.

This prospective observational cohort study aims to evaluate the relationship between dynamic NT-proBNP changes and clinical decongestion status in patients with ADHF receiving standard medical treatment.

Adult patients admitted to the cardiac intensive care unit (CCU) with ADHF will be enrolled. All participants will receive routine guideline-directed medical therapy, including diuretic treatment and other appropriate heart failure management, according to the decisions of their treating physicians. The study team will not influence treatment selection, treatment intensity, or clinical decision-making.

During the first 72 hours after admission, serial NT-proBNP measurements will be obtained to characterize temporal changes in NT-proBNP levels. The percentage change of NT-proBNP from baseline (ΔNT-proBNP%) will be calculated. Clinical decongestion status will be assessed simultaneously using standardized clinical evaluations, including signs of systemic and pulmonary congestion and, when clinically appropriate, bedside imaging parameters.

The primary objective of this study is to determine whether dynamic changes in NT-proBNP levels are associated with achievement of clinical decongestion during hospitalization under current standard treatment.

Secondary objectives include evaluating:

The relationship between NT-proBNP trajectory and time to complete decongestion; The association between NT-proBNP changes and renal function alterations, including acute kidney injury or worsening renal function; The feasibility of serial bedside NT-proBNP monitoring in real-world clinical practice.

This study is exploratory and hypothesis-generating. It does not evaluate the efficacy of NT-proBNP-guided therapy and does not introduce any treatment intervention. The results will provide clinical evidence regarding whether NT-proBNP dynamics may serve as an objective biomarker reflecting decongestion response during ADHF hospitalization.

Inclusion criteria

• Adults aged ≥18 years.
• Patients hospitalized in the cardiac intensive care unit (CCU) with a diagnosis of acute decompensated heart failure (ADHF).
• Presence of clinical evidence of congestion at admission, including at least one of the following:
• Symptoms or signs of volume overload (e.g., dyspnea, orthopnea, peripheral edema, elevated jugular venous pressure).
• Pulmonary congestion based on physical examination or imaging findings.
• Other clinically recognized evidence of congestion judged by the treating physician.
• Patients receiving standard guideline-directed medical treatment for acute decompensated heart failure, including intravenous diuretic therapy according to clinical practice.
• Ability to provide informed consent or availability of a legally authorized representative to provide consent.

Exclusion criteria

• Cardiogenic shock or requirement for immediate mechanical circulatory support.
• End-stage kidney disease requiring maintenance dialysis or renal replacement therapy at admission.
• Acute conditions requiring urgent intervention that may interfere with study assessments, including acute coronary syndrome requiring immediate revascularization or acute pulmonary embolism.
• Clinical conditions in which NT-proBNP interpretation is considered unreliable or inappropriate by the investigator.
• Expected survival of less than 72 hours, early transfer from the CCU, or inability to complete the core observation period.
• Any other condition considered inappropriate for participation by the investigator.