Effectiveness of bronchoscopic lung volume reduction using unilateral endobronchial valve: a systematic review and meta-analysis

Miyoung Choi,1 Worl Suk Lee,1 Min Lee,1 Kyeongman Jeon,2 Seungsoo Sheen,3 Sanghoon Jheon,4 Young Sam Kim5 1National Evidence-Based Healthcare Collaborating Agency, Seoul, Republic of Korea; 2Division of Pulmonary and Critical Care Medicine, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea; 3Department of Pulmonary and Critical Care Medicine, Ajou University School of Medicine, Suwon, Republic of Korea; 4Department of Thoracic and Cardiovascular Surgery, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seoul, Republic of Korea; 5Department of Internal Medicine, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea Background: Bronchoscopic lung volume reduction (BLVR) can be suggested as an alternative for surgical lung volume reduction surgery for severe emphysema patients. This article intends to evaluate by systematic review the safety and effectiveness of BLVR using a one-way endobronchial valve.Methods: A systematic search of electronic databases, including MEDLINE, EMBASE, and the Cochrane Library, as well as eight domestic databases up to December 2013, was performed. Two reviewers independently screened all references according to selection criteria. The Scottish Intercollegiate Guidelines Network criterion was used to assess quality of literature. Data from randomized controlled trials were combined and meta-analysis was performed. Results: This review included 15 studies. Forced expiratory volume in 1 second (FEV1) improved in the intervention group compared with the control group (mean difference [MD]=6.71, 95% confidence interval [CI]: 3.31–10.11). Six-minute walking distance (MD=15.66, 95% CI: 1.69–29.64) and cycle workload (MD=4.43, 95% CI: 1.80–7.07) also improved. In addition, St George’s Respiratory Questionnaire score decreased (MD=4.29, 95% CI: -6.87 to -1.71) in the intervention group. In a subgroup analysis of patients with complete fissure, the FEV1 change from baseline was higher in the BLVR group than in the control group for both 6 months (MD=15.28, P<0.001) and 12 months (MD=17.65, P<0.001), whereas for patients with incomplete fissure, FEV1 and 6-minute walking distance showed no change. One-year follow-up randomized controlled trials reported deaths, although the cause of death was not related to BLVR. Respiratory failure and pneumothorax incidence rates were relatively higher in the BLVR group, but the difference was not significant.Conclusion: BLVR may be an effective and safe procedure for the treatment of severe COPD patients with emphysema, based on existing studies. Keywords: endobronchial valve, bronchoscopic valve lung volume reduction, systematic review, meta-analysis&nbsp