Targeted segmental volume reduction with vapor ablation in emphysema results in reduced RV and clinically meaningful improvement (CMI) in FEV1

Abstract

Introduction: In emphysema hyperinflation within a lobe occurs heterogeneously at the segmental level, meaning that certain segments are more hyperinflated than their neighboring segments. Volume reduction leading to CMI has formerly only been achievable on a lobar basis, resulting in indiscriminate treatment of all segments irrespective of disease severity. We hypothesized that targeting the most hyperinflated segments would result in clinically meaningful reduction of residual volume (RV) while preserving lung parenchyma. Objective: Whether targeted reduction of most hyperinflated upper lobe segments results in reduced RV and CMI in FEV 1 Methods: In the STEP-UP RCT, 45 patients received bilateral vapor ablation in 1 or 2 of the more hyperinflated upper lobe segments over 2 procedures. Difference in RV and FEV 1 was calculated using baseline and 6-month follow up patient data for the control and treatment arm. Results: Change in RV at 6 months showed a correlation with FEV 1 change (r=0.39) Conclusions: Targeted reduction of the most hyperinflated upper lobe segments with vapor ablation results in RV reduction, which correlates with improvement in FEV 1 . This targeted method of bronchoscopic lung volume reduction preserves functional lung parenchyma. In the event of future disease progression, remaining segments may be targeted for volume reduction to yield sustained benefit.