Predictors of clinical outcome in emphysema patients with atelectasis following endoscopic valve therapy: A retrospective study

Background and objective The aim of endoscopic valve therapy in patients with emphysema is complete lobar atelectasis of the most emphysematous lobe. However, even after the radiological advent of atelectasis, great variability in clinical outcomes can be observed. Methods The baseline clinical measures (vital capacity (VC), forced expiratory flow in 1 s (FEV1), residual volume (RV) and 6-min walk test (6-MWT)) and computed tomography variables (low attenuation volume (LAV) of the target lobe, LAV% of the target and the ipsilateral untreated lobe and LAV of the target lobe to LAV of the target lung and to LAV of the total lung) of 77 patients with complete atelectasis following valve therapy were retrospectively examined to determine their impact on patient´s outcome (changes in VC, FEV1, RV and 6-MWT from baseline to the time of atelectasis). Results Low attenuation volume of the target lobe to LAV of the target lung predicts a significant FEV1 improvement in patients with complete lobar atelectasis following valve therapy. A 10% difference in that computed tomography predictor was associated with a 82-mL improvement in FEV1 (P = 0.006). Lower 6-MWT scores, low VC and high RV at baseline were significantly associated with greater improvement in the respective parameter (all P < 0.001). Conclusion Low attenuation volume of the target lobe to LAV of the target lung and baseline clinical measures seem to significantly predict clinical outcomes in patients with complete lobar atelectasis following valve treatment.