Bronchoscopic lung volume reduction by endobronchial valve in advanced emphysema: the first Asian report

Abstract

Purpose: Endobronchial valve (EBV) therapy is increasingly being seen as a therapeutic option for advanced emphysema, but its clinical utility in Asian populations, who may have different phenotypes to other ethnic populations, has not been assessed.

Patients and methods: This prospective open-label single-arm clinical trial examined the clinical efficacy and the safety of EBV in 43 consecutive patients (mean age 68.4±7.5, forced expiratory volume in 1 second [FEV1] 24.5%±10.7% predicted, residual volume 208.7%±47.9% predicted) with severe emphysema with complete fissure and no collateral ventilation in a tertiary referral hospital in Korea.

Results: Compared to baseline, the patients exhibited significant improvements 6 months after EBV therapy in terms of FEV1 (from 0.68±0.26 L to 0.92±0.40 L; P<0.001), 6-minute walk distance (from 233.5±114.8 m to 299.6±87.5 m; P=0.012), modified Medical Research Council dyspnea scale (from 3.7±0.6 to 2.4±1.2; P<0.001), and St George's Respiratory Questionnaire (from 65.59±13.07 to 53.76±11.40; P=0.028). Nine patients (20.9%) had a tuberculosis scar, but these scars did not affect target lobe volume reduction or pneumothorax frequency. Thirteen patients had adverse events, ten (23.3%) developed pneumothorax, which included one death due to tension pneumothorax.

Conclusion: EBV therapy was as effective and safe in Korean patients as it has been shown to be in Western countries. (

Trial registration: ClinicalTrials.gov: NCT01869205).

Keywords: bronchoscopy; chronic obstructive pulmonary disease; collateral ventilation; fissure integrity; treatment outcome.

Figure 1

An example of target lobe selection on the basis of dual-source computed tomography. Notes: (A) Lung setting image. (B) Quantitative perfusion image. The perfusion is presented from red (normal) to black (no perfusion). (C) Quantitative analysis of perfusion and volume for each lobe. In this patient, the left lower lobe was selected as target lobe (as shown by the bold) since it had the lowest fraction of perfusion compared with its volume (0.20/0.33). It means that left lower lobe is the most emphysematous and hyperinflated.

Figure 2

Flow chart indicating patient disposition in the study. Abbreviations: BLVR, bronchoscopic lung volume reduction; EBV, endobronchial valve; FEV₁, forced expiratory volume in 1 second; SGRQ, St George’s Respiratory Questionnaire; 6MWD, 6-minute walk distance test.

Figure 3

Primary outcomes 3 and 6 months after endobronchial valve therapy relative to baseline. Abbreviations: FEV₁, forced expiratory volume in 1 second; 6MWD, 6-minute walk distance test; mMrc, modified Medical Research Council dyspnea scale; SGRQ, St George’s Respiratory Questionnaire.

Figure 4

Proportion of patients whose clinical outcomes after endobronchial valve therapy exceed the minimum clinically important differences FEV₁, 6MWD and SGRQ. Abbreviations: FEV₁, forced expiratory volume in 1 second; 6MWD, 6-minute walk distance; SGRQ, St George’s Respiratory Questionnaire.