Right-Sided Pleural Effusion in Heart Failure: Mechanism and Management

In congestive heart failure (CHF), elevated left-sided pressures transmit backward: LA → pulmonary veins → capillaries → pulmonary edema. When severe or chronic, pressure rises in pulmonary artery → right ventricle → systemic veins → hepatic congestion → transudation into pleural space (predominantly right due to anatomic factors: larger right pleural surface, liver buffer on left).

Clinical Implications

• Effusion size correlates with HF severity.
• Bilateral common; unilateral right > left.
• Diuresis (loop diuretics) reduces preload → resolves effusion.
• Thoracentesis if large/compromising; fluid analysis confirms transudate (Light’s criteria negative).

Monitoring

Serial weights, BNP/NT-proBNP, echo (RV function, PA pressure), CXR. Optimize GDMT (ARNI, beta-blocker, MRA, SGLT2i).