Role of Thrombectomy Technique in Alteplase Bridging Intravenous Thrombolysis for Basilar Artery Occlusion

Background: Endovascular treatment (EVT) is the standard of care for acute basilar artery occlusion (BAO) although the role of bridging intravenous thrombolysis (IVT) with alteplase prior to EVT remains debated. Whether the effect of bridging IVT differs across EVT techniques has not been systematically assessed. Methods: We conducted a retrospective multicenter analysis including consecutive patients with BAO treated with EVT at 7 comprehensive stroke centers between 2019 and 2023. Patients were stratified according to first-line thrombectomy technique: direct thromboaspiration (BAOTA), stent retriever (BAOST), or combined approach (BAOCO). Outcomes were analyzed using inverse probability weighting to adjust for baseline imbalances. The primary end point was 90-day favorable functional outcome (modified Rankin Scale 0-3) and ordinal 90-day modified Rankin Scale shift. Secondary end points included 90-day functional independence (modified Rankin Scale 0-2), successful reperfusion, 90-day mortality, hemorrhagic transformation, and symptomatic intracerebral hemorrhage. Sensitivity analyses with trimmed weights and subgroup analyses were prespecified. Results: A total of 517 patients were included: 200 BAOTA, 260 BAOST, and 57 BAOCO. In patients with BAOTA, bridging IVT was associated with higher rates of 90-day favorable outcome (risk ratio [RR] 1.47, 95% CI 1.00-2.16) and improved 90-day modified Rankin Scale shift. In patients with BAOST bridging IVT significantly reduced symptomatic intracerebral hemorrhage risk (RR 0.27, 95% CI 0.09-0.77) while in patients with BAOCO functional independence was numerically more frequent among patients treated with bridging IVT (RR 1.91, 95% CI 1.08-3.37). Conclusions: Bridging IVT was associated with differences in clinical and safety outcomes across EVT strategies. However, no statistically significant interaction was observed between treatment allocation and EVT technique. Therefore, these findings should be interpreted as descriptive and hypothesis-generating rather than evidence of true differences in treatment effect.