Heart failure-related pleural effusion: determinants of pleural drainage and predictors of mortality in a cohort of 1372 patients

Background Heart failure (HF) is one of the most common causes of pleural effusion (PE), yet data on its management and prognosis in patients undergoing diagnostic thoracentesis are limited. The significance of invasive pleural interventions remains uncertain. Methods We conducted a retrospective analysis of a prospectively maintained pleural database, including consecutive patients with HF-related PE who underwent diagnostic thoracentesis. Clinical characteristics, pleural findings, need for invasive pleural management (therapeutic thoracentesis [TT] or indwelling pleural catheter [IPC]), and mortality were assessed. Fine–Gray competing-risk models and Cox regression were applied. Results A total of 1372 patients were included (median age 85 years). During follow-up, 726 patients (53%) required at least one TT and 81 (6%) received an IPC. In the competing-risk analysis, effusion size ≥½ hemithorax (sHR 2.33), bilateral effusion (sHR 1.37), pleural fluid albumin >1.2 g·dL −1 (sHR 1.23), and male sex (sHR 1.20) were independently associated with invasive pleural management. Median survival was 14 months, with mortality rates of 50% at 1 year and 70% at 2 years. Mortality was independently associated with advanced age, elevated serum NT-proBNP, renal dysfunction, and hypoalbuminemia, whereas pleural characteristics and invasive pleural management were not. Conclusion In patients with HF-related PE undergoing diagnostic thoracentesis, mortality is high and primarily driven by systemic markers of advanced HF. Invasive pleural interventions are frequently required in patients with large or bilateral effusions. In descriptive comparisons, survival was similar regardless of pleural intervention status, although causal inference is precluded by the observational design and time-dependent nature of intervention.