Key Points
Question What are the outcomes among patients undergoing endovascular thrombectomy for vertebrobasilar artery occlusion beyond 24 hours from the patient’s last known well time?
Findings In this cohort study of 202 patients with vertebrobasilar artery occlusion treated beyond 24 hours after last known well time, endovascular thrombectomy with best medical treatment was associated with a higher rate of good functional outcome at 90 days and lower mortality compared with best medical treatment alone.
Meaning These findings suggest that endovascular thrombectomy may be associated with improved functional outcomes in patients with vertebrobasilar artery occlusion presenting beyond 24 hours, underscoring the need for randomized clinical trials to evaluate the treatment’s effectiveness.
Abstract. 
Importance The efficacy and safety of endovascular thrombectomy (EVT) plus best medical treatment (BMT) for vertebrobasilar artery occlusion beyond 24 hours remain uncertain.
Objective To evaluate outcomes associated with EVT in patients treated beyond 24 hours after last known well time due to vertebrobasilar artery occlusion.
Design, Setting, and Participants This multicenter, prospective cohort study enrolled patients between 2019 and 2024 from 11 comprehensive stroke centers across China. Eligible patients with vertebrobasilar artery occlusions treated beyond 24 hours after the estimated onset were included.
Exposures Patients were categorized into 2 groups: those who underwent EVT plus BMT and those who received BMT alone.
Main Outcomes and Measures The primary outcome was good functional status (modified Rankin Scale score, 0-3) at 90 days. Safety outcomes included symptomatic intracranial hemorrhage within 24 hours and 90-day mortality.
Results Among 202 patients with vertebrobasilar occlusion (158 male [78.2%]; median [IQR] age, 64.0 [56.2-70.0] years), 101 patients received EVT plus BMT and 101 patients received only BMT. The median (IQR) posterior circulation Acute Stroke Prognosis Early Computed Tomography Score was 8 (8-9), and the median (IQR) of time of onset to admission was 48 (24-96) hours. In the primary analysis using propensity score matching, 71 patients with EVT plus BMT had a higher rate of a good functional outcome at 90 days compared with 71 patients receiving BMT alone (41 patients [57.7%] vs 32 patients [45.1%]; adjusted risk ratio [aRR], 1.35 [95% CI, 1.02-1.79]). EVT plus BMT compared with BMT alone showed lower mortality (9 patients [12.7%] vs 20 patients [28.2%]; aRR, 0.27 [95% CI, 0.08-0.81]); differences in rates of symptomatic intracranial hemorrhage were not statistically significant (4 patients [5.6%] vs 0 patients; P = .13). A similar advantage in functional outcome for EVT plus BMT (aRR, 1.33 [95% CI, 1.04-1.71]) was observed in the inverse probability of treatment weighting analysis.
Conclusions and Relevance In this study, EVT plus BMT was associated with improved functional outcomes and survival rates at 90 days and a nonsignificant but numerically higher frequency of symptomatic intracranial hemorrhage than BMT alone in patients treated beyond 24 hours after last known well time. These findings suggest that randomized clinical trials comparing EVT with BMT in patients with acute vertebrobasilar artery occlusion are warranted.
