Woven EndoBridge device shape modification can be mitigated with an appropriate oversizing strategy: a VasoCT based study

BACKGROUND: The Woven EndoBridge (WEB) shape modification (WShM) during follow-up may be a potential cause of poor angiographic outcomes. WShM predisposing factors have not yet been determined. Our systematic use of rotational cone beam computed tomography (VasoCT) imaging during follow-up allowed us to perform the first quantitative analysis of the shape of WEBs over time. Our goal was to identify possible strategies to reduce the occurrence of this phenomenon. METHODS: All patients treated in our hospital with a WEB device between October 2015 and January 2019 were included. Using VasoCT acquisitions, systematically performed after implantation and during follow-up, we analyzed WEB morphology. WShM was defined as the percentage reduction in the distance between the two WEB markers. RESULTS: Sixty-three aneurysms treated with a WEB device were finally included in this analysis. At the last follow-up (mean 15.5 months), mean WShM was 48%±24. The mean WShM was significantly higher in the aneurysm recurrence group than in the adequate occlusion group (51±6.5% vs 36±3.4%, difference 15% points (95% CI 0.7 to 30); p<0.05). Conversely, the extent of WShM did not directly correlate with occlusion rates. Indeed, 32% of completely occluded aneurysms presented severe WShM (≥50%). Importantly, the absence of WShM guaranteed complete occlusion in our study (n=12). We demonstrated that oversizing the width of the WEB significantly correlated with WShM reduction during follow-up (r=-0.38, p=0.002). CONCLUSION: WShM can be partly overcome by use of an appropriate width oversizing strategy that could lead to improved angiographic results.