Abstract WMP95: Values Of Collateral Status On Treatment Decision-making And Individualizing Time Window In Patients With Acute Basilar Artery Occlusion In Endovascular Treatment

Bankground: Basilar artery occlusion (BAO) is related to a high risk of morbidity and mortality. Our aim was to investigate the values of posterior circulation collateral score (PC-CS) on treatment decision-making and individualizing time window of patients with acute BAO in endovascular treatment. Methods: The BASILAR study was a nationwide prospective registry of consecutive patients presenting with symptomatic, radiologically confirmed within 24 hours of symptoms onset. Patients were divided into two groups according to the treatment they received: standard medical therapy alone and medical therapy plus endovascular therapy (EVT). We used a 10-points grading system based on computed tomography angiography to quantify the potential for collateral flow in the posterior circulation. We defined modified Rankin Scale score &It;3 within 3 months as favorable outcome, as well as mortality within 90 days were included as primary outcomes. Results: A total of 828 eligible consecutive patients with acute BAO were enrolled in our study with trichotomized PC-CS. EVT was associated with higher rate of favorable outcomes (adjusted odds radio with 95% CI, 7.02 [1.48-33.29]; 4.84[1.82-12.87] and 6.16 [2.69-14.08]; respectively) and lower mortality (57.4% versus 84.8%, P =0.001; 47.4% versus 75% , P &It ; 0.001 and 34.9% versus 58.8%, P &It;0.001) than standard medical therapy group in the trichotomized PC-CS. And higher PC-CS is associated with favorable outcomes in EVT group. More importantly, the patients received endovascular treatment with poor collateral circulation (PC-CS 0-3) could benefit only within 6 hours of symptom onset, while the time window will be extended to 24 hours in the patients with good collateral circulation (PC-CS 4-10). Conclusions: The PC-CS is a vital marker for predict favorable outcomes and treatment decision-making and individualizing time window in patients with acute BAO in endovascular treatment.