Back to Topics
Interventional
Endobronchial Valves for Severe Emphysema
Added by Dr. Andrew · Last updated 2024-01-15
Overview
Endobronchial valves (EBV) are one-way valves placed bronchoscopically to achieve lobar atelectasis in patients with severe heterogeneous emphysema, reducing hyperinflation and improving lung function. Patient selection requires intact interlobar fissures (no collateral ventilation).
Key Points
- 1Mechanism: one-way valve allows air out but not in → lobar atelectasis → reduces hyperinflation
- 2Devices: Zephyr (Pulmonx) — FDA approved 2018; Spiration Valve System (Olympus)
- 3Patient selection: severe emphysema (FEV1 15–45%), hyperinflation (RV >175%), heterogeneous disease, intact fissures (no collateral ventilation)
- 4Collateral ventilation assessment: Chartis system (quantitative) or high-resolution CT fissure analysis
- 5LIBERATE trial (Zephyr): FEV1 improved +14.7% vs +2.1% at 12 months; improved 6MWD and QoL
- 6Complications: pneumothorax (20–25% — most common), valve migration, COPD exacerbation
Clinical Pearls
- Complete fissure on CT: 90% probability of no collateral ventilation — can proceed without Chartis
- Post-EBV pneumothorax: occurs within 72 hours — admit for observation after procedure
- Lobar atelectasis on CXR at 30 days = successful treatment
- LVRS (lung volume reduction surgery) is alternative — similar outcomes but higher morbidity
Board High-Yield
Exam Focus- LIBERATE trial: Zephyr EBV improved FEV1 by 14.7% at 12 months in heterogeneous emphysema
- Intact fissure (no collateral ventilation) = prerequisite for EBV success
- Pneumothorax: most common complication (~20–25%) — occurs early post-procedure
- NETT trial: LVRS improves survival in upper-lobe predominant emphysema with low exercise capacity
- Contraindications: homogeneous emphysema, collateral ventilation, active infection, FEV1 <15%
ABIM Exam Weight
5%
Interventional Pulmonology represents approximately 5% of the PCCM certification exam.