Pleural Effusion and Invasive Hemodynamic Measurements in Advanced Heart Failure.

Background: Pleural effusion is present in 50% to 80% of patients with acute heart failure, depending on image modality. We aim to describe the association between the presence and size of pleural effusion and central hemodynamics, including pulmonary capillary wedge pressure (PCWP) in an advanced heart failure population.

Methods: An observational, cross-sectional study in a cohort of patients with advanced heart failure (left ventricular ejection fraction ≤45%) who underwent right heart catheterization at The Department of Cardiology at Copenhagen University Hospital, Rigshospitalet, Denmark, between January 1, 2002 and October 31, 2020. The presence and size of pleural effusion were determined by a semiquantitative score of chest x-rays or computed tomography scans performed within 2 days of right heart catheterization.

Results: In 346 patients (50±13 years; 78% males) with median left ventricular ejection fraction of 20% (15-25), we identified 162 (47%) with pleural effusion. The pleural effusion size was medium in 38 (24%) and large in 30 (19%). Patients with pleural effusion had a 4.3 mm Hg (2.5-6.1) higher PCWP and 2.4 mm Hg (1.2-3.6) higher central venous pressure (P<0.001 for both). Patients with a medium/large pleural effusion had statistically significantly higher filling pressures than patients with a small effusion. Higher PCWP (odds ratio [OR], 1.06 [1.03-1.10]) and central venous pressure (OR, 1.09 [1.05-1.15]) were associated with pleural effusion in multivariable logistic regression adjusted for age, sex, and heart failure medications (P<0.001 for both). In a subgroup of 204 (63%) patients with serum albumin data, PCWP (OR, 1.06 [1.01-1.11]; P=0.032), central venous pressure (OR, 1.14 [1.06-1.23]; P<0.001) and serum albumin level (OR, 0.89 [0.83-0.95]; P<0.001) were independently associated with the presence of a medium/large-sized pleural effusion.

Conclusions: In patients with left ventricular ejection fraction ≤45% undergoing right heart catheterization as part of advanced heart failure work-up, pleural effusion was associated with higher PCWP and central venous pressure and lower serum albumin.