Effect of bronchoscopic lung volume reduction using endobronchial valves on endothelial function in severe COPD: A randomized controlled trial

<bold>Background:</bold> Cardiovascular morbidity in COPD patients is an emerging research field. The mechanisms still have to be elucidated. <bold>Aim:</bold> This study investigates whether bronchoscopic lung volume reduction (BLVR) using endobronchial valves (EBV) is associated with improved endothelial function. <bold>Methods:</bold> In a randomized controlled trial with COPD patients scheduled for BLVR, the intervention group underwent immediate BLVR after baseline assessment, with a follow-up at six weeks. The control group had a reassessment at six weeks, followed by BLVR. The outcome was endothelial function measured by flow-mediated dilatation (FMD) of the brachial artery. <bold>Results:</bold> 26 patients (mean (SD) age 65 (6) years, 61% female, FEV1% pred. 30 (8)) were included in the trial. Of those, 14 patients were randomized to the intervention and 12 to the control group. Target lobe atelectasis was successfully induced in nine patients of the BLVR group. Baseline FMD was comparable between intervention and control groups (mean (SD) FMD of 2.41 (0.96) and 2.85 (0.68)%, respectively). FMD significantly increased in the intervention group compared to the control group (absolute mean (95% CI) difference of +2.22 (1.64/2.81)%, p<0.001). BLVR resulted in a relative reduction in mean (SD) RV/TLC of -17 (7)% and an increase in FEV1 of 24 (29)% compared to baseline. Improvement in FMD was correlated to the extent of reduction in RV/TLC irrespective of baseline FMD (coefficient (95% CI) of −0.17 (−0.22/-0.12), p<0.001). <bold>Conclusion:</bold> Successful BLVR with EBV significantly improves endothelial function in severe COPD, suggesting an association between hyperinflation and cardiovascular morbidity.