Impact of intravenous albumin administration on diuretic response in acute heart failure: a real-world retrospective study

Acute heart failure (AHF) remains a leading cause of hospitalization and mortality among patients with cardiovascular disease (1). Restoring euvolemia through effective diuretic therapy is a cornerstone of AHF management, as persistent congestion is a key predictor of adverse outcomes (2). Currently, there is limited evidence supporting the co-administration of albumin and furosemide in AHF.

To investigate whether the co-administration of intravenous albumin with loop diuretics enhances diuretic response and facilitates more effective decongestion in patients admitted to an intensive cardiac care unit (ICCU) for AHF.

We conducted a retrospective observational study involving 50 patients admitted to the ICCU of a major tertiary hospital in Spain for AHF between September 2017 and 2025. Eligible patients had documented hourly urine output for at least 24 hours before and after the initial albumin infusion and received intravenous furosemide (>40 mg within the preceding 24 hours, administered either as bolus or continuous infusion) in combination with albumin. Patients undergoing renal replacement therapy were excluded.

Total urine output was quantified during the 24 hours preceding and following albumin administration. Additional data collected included total fluid intake, laboratory and hemodynamic parameters, and baseline clinical characteristics.

A mixed-effects linear regression model for repeated measures was used to assess the independent effect of albumin administration on diuretic response, adjusting for furosemide dose, fluid intake, mean arterial pressure, use of inotropes and/or vasopressors, estimated glomerular filtration rate (eGFR), and serum sodium concentration.

The mean age of the cohort was 74.6 years, and 28% were women. Baseline characteristics and heart failure etiology are summarized in Figure 1. The mean albumin dose administered within 24 hours was 30.6 g (SD: 7.9).

Urine output significantly increased in the 24 hours following albumin infusion compared with the preceding 24 hours, with a mean adjusted difference of 717 mL (95% CI 385–1050; p<0.001; Figure 2). Higher baseline serum sodium levels were independently associated with a reduced diuretic response (p=0.040). A positive trend was observed between higher eGFR and increased urine output (p=0.052). No other covariates showed a significant association with changes in diuretic response.

In this real-world retrospective study of patients with AHF admitted to a tertiary ICCU, intravenous albumin administration was independently associated with a significant increase in urine output within 24 hours. These findings suggest that albumin may enhance diuretic efficacy and could serve as a valuable adjunctive strategy to optimize decongestion in selected patients. Prospective studies are warranted to confirm these results.

Baseline characteristics