Prognostic impact of pleural effusion in acute heart failure and its link to diuretic therapy

The prognostic significance of pleural effusion in patients with acute heart failure remains insufficiently defined. Our objective was to evaluate the association between pleural effusion and long-term outcomes, stratified by loop diuretic treatment.

This retrospective study included 656 elderly patients hospitalized for acute heart failure. Patients were stratified by the presence or absence of pleural effusion at admission. The primary endpoint was the composite of all-cause mortality and/or heart failure readmission. Multivariable Cox regression and interaction analyses between pleural effusion and loop diuretic use at discharge were performed.

Median age was 87 (83-90) years, 65.5% were women, and 80.3% had heart failure with preserved ejection fraction. Pleural effusion was present in 40.5% of patients. After multivariable adjustment, a significant interaction was observed between pleural effusion and loop diuretic use for the combined endpoint (P for interaction = 0.043). Among patients with pleural effusion, absence of loop diuretic prescription at discharge was associated with increased risk of death and/or rehospitalization (HR 2.47, 95% CI 1.28-4.77; P = 0.007). Conversely, in patients discharged on loop diuretic, pleural effusion was not significantly associated with mortality and/or rehospitalization (HR 1.21, 95% CI 0.96-1.52; P = 0.101).

In this elderly cohort of patients hospitalized for acute heart failure, the presence of pleural effusion was associated with a higher risk of death and/or readmission. The use of loop diuretic therapy at discharge appeared to attenuate this risk, supporting a potential role of individualized, congestion-guided treatment strategies in this population.