Assessment of efficacy and safety of endoscopic lung volume reduction with one-way valves in patients with a very low FEV(1)

INTRODUCTION: Endoscopic lung volume reduction (ELVR) with one-way valves produces beneficial outcomes in patients with severe emphysema. Evidence on the efficacy remains unclear in patients with a very low forced expiratory volume in 1 s (FEV(1)) (≤20% predicted). We aim to compare clinical outcomes of ELVR, in relation to the FEV(1) restriction. METHODS: All data originated from the German Lung Emphysema Registry (Lungenemphysem Register), which is a prospective multicentric observational study for patients with severe emphysema after lung volume reduction. Two groups were formed at baseline: FEV(1) ≤20% pred and FEV(1) 21–45% pred. Pulmonary function tests (FEV(1), residual volume, partial pressure of carbon dioxide), training capacity (6-min walk distance (6MWD)), quality of life (modified Medical Research Council dyspnoea scale (mMRC), COPD Assessment Test (CAT), St George's Respiratory Questionnaire (SGRQ)) and adverse events were assessed and compared at baseline and after 3 and 6 months. RESULTS: 33 patients with FEV(1) ≤20% pred and 265 patients with FEV(1) 21–45% pred were analysed. After ELVR, an increase in FEV(1) was observed in both groups (both p<0.001). The mMRC and CAT scores, and 6MWD improved in both groups (all p<0.05). The SGRQ score improved significantly in the FEV(1) 21–45% pred group, and by trend in the FEV(1) ≤20% pred group. Pneumothorax was the most frequent complication within the first 90 days in both groups (FEV(1) ≤20% pred: 7.7% versus FEV(1) 21–45% pred: 22.1%; p=0.624). No deaths occurred in the FEV(1) ≤20% pred group up to 6 months. CONCLUSION: Our study highlights the potential efficacy of one-way valves, even in patients with very low FEV(1), as these patients experienced significant improvements in FEV(1), 6MWD and quality of life. No death was reported, suggesting a good safety profile, even in these high-risk patients.