Lung Volume Reduction with Vapor Ablation in the Presence of Incomplete Fissures: 12-Month Results from the STEP-UP Randomized Controlled Study.

BACKGROUND Emphysema patients with collateral ventilation (CV) will not benefit from valve therapy, the most common endoscopic lung volume reduction procedure. A recent randomized controlled trial (STEP-UP) of the alternative bronchoscopic thermal vapor ablation (BTVA) included patients with (CV+) and without interlobar CV (CV-). OBJECTIVES This analysis evaluated the efficacy and safety of the CV+ population following BTVA. METHOD A post hoc fissure analysis of the baseline computed tomography of all treatment and control patients was performed with the VIDA Diagnostics Apollo software. A patient was considered to be CV+ if either of the treated upper lobes was adjacent to a fissure that was <90% complete. The primary endpoints, forced expiratory volume in 1 s (FEV1) and St. George's Respiratory Questionnaire (SGRQ-C), were calculated for these CV+ patients following BTVA and safety results summarized. RESULTS 78% (35/45) of the patients in the treatment arm and 79% (19/24) of the patients in the control arm were found to be CV+. At 12 months, the FEV1 improvement of the treatment arm was 9.2%, as compared with a decrease of 5.4% in the control group, resulting in a mean between-group difference of 14.6% (p = 0.0137). The improvement in SGRQ-C of the treatment arm as compared to the control arm was 8.4 points (p = 0.0712). An increase in respiratory related serious adverse events was observed immediately following treatment, but most resolved with routine care. CONCLUSION BTVA can achieve safe and clinically meaningful improvement in pulmonary function and quality of life in patients with CV. These randomized controlled trial subgroup results offer proof of a viable solution for CV+ patients.