Bronchoscopic Lung Volume Reduction Coil Treatment Success Rate
Bronchoscopic lung volume reduction coil treatment demonstrates modest success with approximately 36% of patients achieving clinically meaningful improvement in exercise capacity (≥54m improvement in 6-minute walk test) at 6 months, though the procedure consistently produces statistically significant improvements in quality of life, lung function, and exercise capacity across multiple trials 1.
Evidence-Based Success Metrics
The GOLD 2017 guidelines acknowledge that two multicenter trials examining nitinol coils showed increases in 6-minute walk distance with coil treatment compared to control, along with smaller improvements in FEV1 and quality of life measured by SGRQ 2. However, the guidelines explicitly state that additional data are needed to define the optimal patient population and compare long-term durability relative to side effects 2.
Quantified Treatment Outcomes
The most rigorous evidence comes from the REVOLENS trial 1, which provides specific success benchmarks:
Primary endpoint success rate: 36% of coil-treated patients achieved ≥54m improvement in 6-minute walk test at 6 months versus 18% in usual care (18% absolute difference, P=0.03)
Mean improvements at 6 and 12 months:
- FEV1: +0.09L and +0.08L respectively (P≤0.002)
- 6-minute walk distance: +21m at both timepoints
- SGRQ: -13.4 and -10.6 points (both clinically meaningful, P<0.001)
- Residual volume: -0.65L and -0.71L
A comprehensive meta-analysis of 680 patients across 8 trials 3 confirms sustained benefits:
- FEV1 improvement: 0.09L at 3 months, 0.07L at 6 months
- Residual volume reduction: -0.45L at 3 months, persisting through 12 months (-0.36L)
- SGRQ improvement: -12.3 points at 3 months, -9.8 points at 12 months (all exceeding minimal clinically important difference of 4 points)
- 6-minute walk distance: +38m at 3 months (improvement not sustained at later timepoints)
Safety Profile and Complications
The procedure carries significant morbidity risk that must be weighed against benefits:
Within 30 days post-treatment 4:
- COPD exacerbations: 6.1%
- Pneumonia: 5.2%
- Pneumothorax: 3.5%
At 3 months, severe complications include 5:
- Severe pneumonia/COPD exacerbations: 47.6%
- Ventilatory failure: 14%
- Mild hemoptysis: common (64%)
Mortality: 4 deaths in coil group versus 3 in usual care within 12 months 1, with no significant difference in overall mortality risk across trials 6.
Patient Selection Criteria
The procedure works regardless of collateral ventilation status 4, 6, which is a key advantage over endobronchial valves. Success is observed in both:
- Heterogeneous emphysema
- Homogeneous emphysema
Optimal candidates based on trial inclusion:
- FEV1: 15-45% predicted (some studies show benefit even <25% predicted 7)
- Residual volume: >175-200% predicted
- Significant hyperinflation refractory to optimal medical therapy
Cost-Effectiveness Considerations
The procedure is extremely costly with poor short-term cost-effectiveness: incremental cost-effectiveness ratio of $782,598 per quality-adjusted life-year, with mean 1-year per-patient cost difference of $47,908 1. This raises serious questions about resource allocation, though long-term cost implications remain unknown.
Clinical Bottom Line
For appropriately selected patients with severe emphysema and hyperinflation (FEV1 <45%, RV >200%), expect approximately one-third to achieve clinically meaningful exercise improvement, with more consistent benefits in quality of life and modest lung function gains sustained through 12 months. The procedure carries substantial complication risks (nearly 50% experiencing serious adverse events) and extraordinary costs.
The GOLD guidelines appropriately classify this as requiring further study to define optimal patient populations 2. Given the evidence, coil therapy should be reserved for highly selected patients with severe symptoms despite maximal medical therapy who are not candidates for lung volume reduction surgery and understand the risk-benefit profile, particularly the high complication rate balanced against modest functional gains.
Critical caveat: The original coil manufacturer has discontinued production 3, and newer generation devices are under development 5, making current evidence a reference point rather than a guarantee of future availability or performance.