Bridging or Direct Thrombectomy in Posterior Circulation Large-Vessel Occlusion Stroke : Analysis of Binational Registries and Meta-Analysis

Abstract

Background and ObjectivesThe role of IV thrombolysis before endovascular thrombectomy (bridging thrombectomy, BT) in posterior circulation large-vessel occlusion stroke remains uncertain. This study evaluated the effectiveness and safety of BT compared with direct thrombectomy (DT) using data from 2 nationwide registries and an updated meta-analysis.MethodsPatients from collaborative registries in Taiwan and South Korea who underwent thrombectomy for vertebral, basilar, and posterior cerebral artery occlusions were included. This observational study included hospital-based registry data with standardized collection of treatments and outcomes. Propensity score matching was applied to adjust for baseline differences between BT and DT groups. Outcomes included 90-day modified Rankin Scale (mRS) score, mortality, successful reperfusion, and symptomatic intracranial hemorrhage (sICH). We also performed a systematic review and meta-analysis of observational studies comparing BT vs DT in posterior circulation large-vessel occlusion stroke.ResultsAmong the combined 9,942 patients, 873 (median age 71, 32% female) who underwent thrombectomy for posterior circulation stroke were analyzed. Of them, 281 received BT and 592 received DT. BT was associated with a lower 90-day mRS score (median 3 vs 4; adjusted odds ratio [OR] 1.44 per 1-point improvement, 95% CI 1.09-1.91) and lower mortality (17.4% vs 26.9%; adjusted OR 0.51, 95% CI 0.33-0.81). The proportions of successful reperfusion (79.3% vs 81.1%) and sICH (2.5% vs 2.9%) were comparable. In propensity score-matched cohorts (n = 205 each), BT remained associated with better functional outcomes (OR 1.44, 95% CI 1.00-2.07) and reduced mortality (matched OR 0.45, 95% CI 0.26-0.78). The meta-analysis, which included 39 studies and 7,288 patients, confirmed that BT was associated with higher odds of achieving 90-day mRS score 0-2 (OR 1.57, 95% CI 1.28-1.94), 90-day mRS score 0-3 (OR 1.33, 95% CI 1.05-1.68), and lower mortality (OR 0.77, 95% CI 0.61-0.97), without an increased risk of sICH (OR 1.01, 95% CI 0.71-1.44).DiscussionBT was associated with better 90-day functional outcomes and lower mortality, without increasing hemorrhagic risk in posterior circulation large-vessel occlusion stroke. These findings support the use of BT in eligible patients, pending further validation from randomized trials.Classification of EvidenceThis study provides Class III evidence that in patients with posterior circulation stroke undergoing thrombectomy, previous IV thrombolysis is associated with better 90-day functional outcomes and lower mortality without increasing hemorrhagic risk.