Intravenous thrombolysis versus endovascular thrombectomy in acute basilar artery occlusion—A multicenter cohort study

BACKGROUND: Randomized controlled trials have demonstrated an improved outcome of basilar artery occlusion (BAO) with endovascular thrombectomy (EVT) compared to best medical treatment. However, a minority of the patients recruited up to 12-24 h from onset in the positive trials received intravenous thrombolysis (IVT), and a trial with a higher IVT rate did not show superiority of EVT. Thus, the efficacy and safety of EVT compared to IVT for BAO remain less clear. AIMS: We aimed to compare outcomes after IVT alone to EVT with or without IVT for acute BAO. METHODS: This international, observational, retrospective study included patients who received recanalization therapy for BAO at six centers between January 2010 and March 2024. The primary outcome was 3-month modified Rankin Scale (mRS) score 0-3, and secondary outcomes comprised mRS 0-2, ordinal mRS, mortality, and symptomatic intracranial hemorrhage. Outcomes after IVT versus EVT ± IVT were compared using inverse probability-weighted regression adjustment models adjusting for known predictors of outcome in BAO and baseline variables differing between the treatment groups. Interaction of the treatment group with symptom severity and onset-to-treatment time was tested. RESULTS: Of 523 patients with BAO (median age 69, 35.2% women), 28.9% received IVT and 71.1% EVT ± IVT. The IVT-alone group had a lower baseline National Institutes of Health Stroke Scale score (median 11 vs 15) but equally extensive ischemic changes in baseline imaging. After inverse probability-weighted regression adjustment, the IVT-alone group had higher odds of mRS 0-3 (adjusted odds ratio (aOR) = 2.33 [95% confidence interval (CI) = 1.31-4.12]), mRS 0-2 (aOR = 1.93 [95% CI = 1.12-3.30]), lower median mRS (aOR = 1.81 [95% CI = 1.21-2.71]), and lower mortality (aOR = 0.53 [95% CI = 0.29-0.97]), but no difference in symptomatic intracranial hemorrhage (aOR = 0.81 [95% CI = 0.28-2.36]). No interactions for the primary outcome were found. CONCLUSION: In this study, patients with BAO had better outcome after IVT than EVT ± IVT independent of symptom severity and time from onset. Although the non-randomized design of the study warrants caution, the results encourage further trials comparing EVT and IVT to guide recanalization therapy in BAO patients.Data access statement:Anonymized data are available upon reasonable request to the corresponding author following the national legislation.