Bridging Therapy versus Direct Mechanical Thrombectomy in Acute Basilar Artery Occlusion due to Different Stroke Etiologies

Introduction: Stroke etiology could influence treatment decisions. This study aimed to evaluate the efficacy and safety of bridging therapy (BT) compared to direct endovascular treatment (EVT) in patients with basilar artery occlusion (BAO), stratified by stroke subtype. Methods: Data were collected from the PERSIST multicenter retrospective registry, enrolling patients with acute symptomatic BAO treated with EVT. Stroke subtypes were classified based on the TOAST criteria into large artery atherosclerosis (LAA), cardioembolism (CE), and other causes (Others). A propensity score-matched analysis was performed to compare outcomes between patients receiving BT and those undergoing direct EVT. The primary outcome was a favorable functional outcome (mRS 0-3) at 90 days. Secondary outcomes included functional independence (mRS 0-2), 90-day mortality, and symptomatic intracranial hemorrhage (sICH). Results: A total of 577 BAO patients were included, with 376 patients classified as LAA, 119 as CE, and 82 as other causes. In the LAA subgroup, BT was associated with a higher likelihood of favorable outcomes compared to EVT (53.8% vs. 34.4%; OR: 1.29; 95% CI: 1.02-1.65). In the CE subgroup, BT was associated with an increased likelihood of functional independence (mRS 0-2) at 90 days (OR: 1.57; 95% CI: 1.01-2.51). No significant increase in the risk of sICH or 90-day mortality was observed in any of the subgroups following BT. Conclusion: BT appears to be an effective and safe treatment strategy in patients with BAO, particularly in those with LAA and CE etiologies. BT was associated with better functional outcomes compared to direct EVT without increasing the risk of hemorrhagic complications. These findings suggest that stroke subtype should be considered when tailoring treatment strategies for BAO patients. Further prospective randomized trials are needed to confirm these results.