Bronchoscopic lung volume reduction (BLVR) using bronchial prostheses: a pilot safety and efficacy study

Abstract

Lung volume reduction surgery(LVRS) can provide symptomatic improvement in patients with advanced emphysema. Both the open and video-assisted approaches to LVRS are associated with significant morbidity and mortality. Selective bronchoscopic placement of prostheses into segmental bronchi has the potential to achieve LVRS by promoting absorption atelectasis without an incision or intercostal drainage. Aim: this phase 1 study reports the safety and efficacy of BLVR. Methods: following successful sheep experiments, patients with apical emphysema and hyperinflation (otherwise acceptable for standard approach LVR) had apical bronchoscopic segmental airway placement of one-way valves under general anesthesia. The 4 or 6mm valves were silicone based and mounted in a Nitinol bronchial stent (Emphasys Medical Inc, CA, USA). Placement was over a guidewire under bronchoscopic and fluoroscopic control. Results: 5 patients(2M,3F, age 57-69yrs)underwent BLVR. Mean preoperative FEV1 was 0.72L(0.38-1.02L, 23-34% predicted)with a 6minute walk of 354m(315-402m).6-11 prostheses per patient took 90-135 minutes to obstruct most or all upper lobe segments bilaterally. Inpatient stay was 2-8 days. Relatively minor complications seen include minor exacerabtion of COPD(n 3), hemoptysis, pneumothorax(managed with aspiration only) and lower lobe pneumonia(n 1 for each). Symptomatic improvement is noted in 3 of 5 and the other 2 are currently stable. At 1 month lung function is unchanged in 4 patients and imaging shows collapse in only 1 patient. Conclusion: BLVR is a potentially useful novel therapy for emphysema. This pilot study shows that BLVR protheses can be safely placed into the human lung. The absence of xray lung reduction or spirometric improvement likely indicates significant collateral ventilation is occurring, possibly from previously undescribed interlobar collaterals. Alternatively, valve leakage remains possible. Extended followup studies, with active attempts to collapse the obstructed segments are pending.