Addressing residual and recurrent aneurysms post-Woven EndoBridge device embolization: a systematic review and meta-analysis.

Background: Early literature on the Woven EndoBridge (WEB) device reported 80-90% adequate aneurysm occlusion but low complete occlusion (40-55%). It is uncertain whether residual or recurrent aneurysms require re-treatment to prevent future rupture.

Objective: To systematically review the literature to meta-analyze occlusion and complication rates after re-treatment of these aneurysms.

Methods: PubMed and EMBASE were queried for 're-treatment' of 'recurrent' or 'residual' aneurysms treated with the WEB device. Studies reporting strategies and outcomes were included. Patient and aneurysm characteristics, outcomes, and complications were extracted. Meta-analyses were conducted on variables reported by three or more studies.

Results: We included 15 studies of 220 patients (220 aneurysms) with a mean age of 57.8 years (95% CI 55.1 to 60.7 years). At baseline, 42.8% (95% CI 35% to 51%) of aneurysms were ruptured, had a mean 8.6 mm dome (95% CI 7.3 to 10 mm) and a mean 5.2 mm neck (95% CI 4.7 to 5.7 mm), and 69.85% were at bifurcations (95% CI 47.63% to 85.51%). At mean 11.2 months' follow-up (95% CI 8 to 15.6 months), 75.9% (95% CI 66.1% to 83.5%) had residual dome filling, predominantly from incomplete occlusion in 84.7% of cases (95% CI 66.6% to 93.9%). Endovascular management was used in 82.5% (95% CI 72.6% to 89.3%) of recurrences, with stent-assisted or flow diverter-assisted coil embolization being used in 42.4% (95% CI 32.7% to 52.8%). Overall, complication rates were 8.9% (95% CI 4.9% to 15.6%) thromboembolic and 8% (95% CI 4.3% to 14.2%) device-related. Complete angiographic occlusion after re-treatment was achieved in 64.1% (95% CI 52.6% to 74.2%), of patients, with 15.2% (95% CI 8.8% to 24.9%) requiring additional re-treatment.

Conclusion: Our review reports excellent safety and modest occlusion outcomes with re-treatment of recurrent or residual aneurysms post-WEB embolization. Outcomes with observational management of residual or recurrent aneurysms are lacking, questioning the requirement for re-treatment. Endovascular strategies demonstrated excellent safety and additional re-treatment rates, highlighting their expanding role in post-WEB recurrences.