Clinical and quantitative computed tomography predictors of response to endobronchial lung volume reduction therapy using coils.

Objectives: Bronchoscopic lung volume reduction using coils (LVRC) is a well-known treatment option for severe emphysema. The purpose of this study was to identify quantitative computed tomography (QCT) and clinical parameters associated with positive treatment outcome.
Patients and Methods: The CT scans, pulmonary function tests (PFT), and 6-minute walk test (6-MWT) data were collected from 72 patients with advanced emphysema prior to and at 3 months after LVRC treatment. The procedure involved placing 10 coils unilaterally. Various QCT parameters were derived using Apollo imaging software (VIDA). Independent predictors of clinically relevant outcome (Δ6-MWT ≥ 26 m, ΔFEV ₁ ≥ 12%, ΔRV ≥ 10%) were identified through stepwise linear regression analysis.
Results: The response outcome for Δ6-MWT, for ΔFEV ₁ and for ΔRV was met by 55%, 32% and 42%, respectively. For Δ6-MWT ≥ 26 m a lower baseline 6-MWT ( p = 0.0003) and a larger standard deviation (SD) of low attenuation cluster (LAC) sizes in peripheral regions of treated lung ( p = 0.0037) were significantly associated with positive outcome. For ΔFEV ₁ ≥ 12%, lower baseline FEV ₁ ( p = 0.02) and larger median LAC sizes in the central regions of treated lobe ( p = 0.0018) were significant predictors of good response. For ΔRV ≥ 10% a greater baseline TLC ( p = 0.0014) and a larger SD of LAC sizes in peripheral regions of treated lung ( p = 0.007) tended to respond better.
Conclusion: Patients with lower FEV ₁ and 6-MWT, with higher TLC and specific QCT characteristics responded more positively to LVRC treatment, suggesting a more targeted CT-based approach to patient selection could lead to greater efficacy in treatment response.
Competing Interests: Disclosure KK, KR and SW report no conflicts of interest in this work. RE: Lecture and travel fees from Olympus, Pulmonx and Uptake Medical/Broncus outside the submitted work. MS: Fees for lectures and advisory boards from the following companies: Olympus, Pulmonx, Astra Zeneca, Novartis, Teva, GSK, PneumRx and Boston Scientific outside the submitted work. CH: Stock ownership in medical industry, Stada, GSK; Patents Method and Device for Representing the Microstructure of the Lungs. IPC8 Class: AA61B5055FI, PAN: 20080208038, Inventors: W Schreiber, U Wolf, AW Scholz, CP Heussel; personal fees from Schering-Plough, personal fees from Pfizer, personal fees from Basilea, personal fees from Boehringer Ingelheim, personal fees from Novartis, personal fees from Roche, personal fees from Astellas, personal fees from Gilead, personal fees from MSD, personal fees from Lilly, personal fees from Intermune, personal fees from Fresenius, personal fees from Olympus, personal fees from Siemens, personal fees from MeVis, personal fees from Essex, personal fees from AstraZeneca, personal fees from Bracco, personal fees from MEDA Pharma, personal fees from Intermune, personal fees from Chiesi, personal fees from Covidien, personal fees from Pierre Fabre, personal fees from Grifols, personal fees from Bayer, other from Stada, other from GSK, outside the submitted work. FH: Fees for lectures and advisory boards from Astra, Allmirall, Berlin Chemie, Boehringer, Roche, GSK, Pulmonx, BTG, Olympus, PneumRx, Boston Scientific, Medupdate, Grifols, CSL Behring, Omniamed, Lilly, Novartis, Teva, Uptake and Vital Air, outside the submitted work. DG: Personal fees from Olympus, personal fees from Pulmonx, personal fees from Chiesi, personal fees from Berlin Chemie, personal fees from Astra Zeneca, personal fees from Boehringer Ingelheim, personal fees from Novartis, personal fees from Mundipharma, personal fees from Grifols, outside the submitted work.