Lung volume reduction in emphysema: a pragmatic prospective cohort study

Abstract

Limited guidance exists for the implementation of lung volume reduction interventions in routine clinical care. We designed a pragmatic study to evaluate a strategy including endoscopic lung volume reduction (ELVR) and lung volume reduction surgery (LVRS) in heterogeneous emphysema. This prospective monocentre cohort study evaluated ELVR versus no-ELVR, followed by a cohort study evaluating LVRS. Primary outcome was the proportion of subjects with a forced expiratory volume in 1 s (FEV₁) improvement of ⩾100 mL at 3-month follow-up. Changes in FEV₁, residual volume (RV), 6-min walk distance (6MWD) and quality of life (St George's Respiratory Questionnaire (SGRQ)) were evaluated at 6-month follow-up. Hospital stay and treatment-related serious adverse events were monitored. From 106 subjects screened, 38 subjects were enrolled comparing ELVR (n=20) with no-ELVR (n=18). After 6 months' follow-up, eligible patients were referred for LVRS (n=16) with another 6-month follow-up. At 3-month follow-up, 70% of ELVR compared to 11% of no-ELVR (p<0.001) and 69% of LVRS had an FEV₁ improvement of ⩾100 mL. Between-group differences (mean±sem) for ELVR versus no-ELVR at 6-month follow-up were FEV₁ +0.21±0.05 L; RV -0.95±0.21 L; 6MWD 58±17 m and SGRQ -18±5 points. At 6-month follow-up, within-group differences (mean±sem) for LVRS showed FEV₁ +0.27±0.06 L; RV -1.49±0.22 L and 6MWD +75±18 m. Serious adverse events in 81% versus 45% of subjects (p=0.04) and a median hospital stay of 15 versus 5 days (p<0.001) were observed for LVRS versus ELVR, respectively. This pragmatic prospective cohort study supports a clinical approach with ELVR as a less invasive first option and LVRS as powerful alternative in severe heterogeneous emphysema.

FIGURE 1

Consolidated Standards of Reporting Trials diagram of subject flow through the pragmatic trial. MEET: multidisciplinary emphysema expert meeting; LVRS: lung volume reduction surgery; LTX: lung transplantation; CV: collateral ventilation; ELVR: endoscopic lung volume reduction. ^#: not eligible due to 6-min walk distance >450 m, fissure integrity on computed tomography scan <70%, intralobar heterogeneous emphysema; ^¶: not eligible due to forced expiratory volume in 1 s <20%, body mass index, airflow obstruction, dyspnoea, exercise capacity (BODE) index score ≥7 and homogeneous emphysema; ⁺: subjects did not consent to per-protocol follow-up.

FIGURE 2

Primary end-point: percentage of subjects achieving a ⩾100 mL improvement in post-bronchodilator forced expiratory volume in 1 s in the intention-to-treat population at 3 months. p-value obtained by Fisher's exact test. ELVR: endoscopic lung volume reduction; LVRS: lung volume reduction surgery.

FIGURE 3

Absolute changes from baseline in key outcome measures at 3 and 6 months post-allocation to endoscopic lung volume reduction (ELVR) group, no-ELVR group and lung volume reduction surgery (LVRS) group. Data presented are mean±sem for a) forced expiratory volume in 1 s (FEV₁), b) residual volume (RV), c) 6-min walk distance (6MWD) and d) St George's Respiratory Questionnaire (SGRQ) total score.