Outcomes of endovascular treatment for acute basilar artery occlusion within the extended time window

This study aimed to evaluate the effectiveness and safety of endovascular treatment (EVT) in patients with acute basilar artery occlusion (ABAO) within the extended time window (6-24 h).

This study was a subgroup analysis of the BASILAR registry. Patients were divided into the EVT and SMT groups. The primary outcome was the distribution of modified Rankin Scale (mRS) scores at 90 days. Safety outcomes included 90-day mortality and symptomatic intracerebral hemorrhage (sICH) within 48 h. To minimize potential confounding, propensity score matching (PSM) and inverse probability of treatment weighting (IPTW) analyses were performed.

Among 829 ABAO patients, 204 eligible patients within the extended time window were included. Compared with the SMT group, the EVT group demonstrated significantly greater odds of a favorable shift in mRS distribution (adjusted odds ratio [aOR] 4.20, 95% confidence interval [CI] 1.82-10.38, P = 0.001) and lower mortality (aOR 0.20, 95% CI 0.07-0.57, P = 0.002) at 90 days. The superiority of EVT over SMT in clinical outcomes persisted at 1 year. Critically, no significant differences were observed in mRS distribution and safety outcomes between ABAO patients receiving EVT in the early time window (0-6 h) versus extended time window (6-24 h) during both short-term and long-term follow-up. All outcomes demonstrated robust consistency after PSM and IPTW.

In ABAO patients within the extended time window, EVT demonstrated superior functional outcomes and lower mortality. Importantly, ABAO patients receiving EVT in the extended time window achieved clinical outcomes comparable to those treated within the early time window.