Endobronchial valves: 1st Multicenter retrospective study on the 2-step approach

Background: Although the endobronchial valves (EBV) were successfully developed as treatment for severe emphysema, its main complication, pneumothorax, remained an important concern.

Objective: To assess whether the placement of Zephyr© endobronchial valves throughout 2 procedures instead of 1 minor the frequency of pneumothorax without lowering the benefits of such treatment.

Methods: This retrospective study was conducted in 15 pulmonology department in France. All the patients met the inclusion criteria of the recommendation set by the expert panel on the Endoscopic Lung Volume Reduction (ELVR) updated in 2019. As recommended, all the scan were analyzed with the StratX© (PulmonX Corporation, Redwood city, CA) protocol, and completed by a Chartis© (PulmonX Corporation, Redwood city, CA) in case of questionable fissure. During the first procedure, all but the most proximal sub-segment of the targeted lobe were occluded. One month after, EBV were placed in the bronchus of the last subsegment. All patients were evaluated before and 3 months after the second procedure.

Results: Between March 2019 and December 2020, 96 patients received EBV treatment. 12 patients (12.5%) presented a pneumothorax (3 after the 1st step and 9 after the 2nd procedure). Beside pneumothorax, the main adverse event was exacerbation (10.4%) and pneumonia (4.1%). No death were reported. Significant improvement were found for FEV1 (14.6 ± 25.3%), RV (- 0.69 ± 2.1 L), 6MWT (34.8 ± 45.9 m), BODE Score (-1.41 ± 1.41pts), and mMRC scale (-0.85 ± 0.7pts). These results are compared not only to the results previously published using the usual approach but also to our previous publication evaluating the 2-step approach. Some patients presented authentic segmental atelectasis despite infralobar treatment.

Conclusion: Placing EBV during 2 procedures instead of one led to a significant decrease of post treatment pneumothoraces without increasing the rate of other complications. It does not seem to alter the benefits of such therapy for severe emphysema. These results must be confirmed by launching a multicenter, prospective, randomized, controlled study to compare the frequency of pneumothorax and the efficacy of this new approach with the usual one-time procedure.