LAUSR

Background: Successful recanalization following endovascular thrombectomy (EVT) in vertebrobasilar artery occlusions (VBAOs) does not uniformly translate into favorable functional outcomes. Identifying predictors of futile recanalization is critical for improving patient selection and treatment strategies. This study aimed to compare patients with good versus poor functional outcomes despite successful recanalization in VBAO and to establish predictive factors for futile recanalization. Methods: We retrospectively analyzed patients who achieved successful recanalization after EVT for VBAO from a prospectively maintained database between 2014-2024. Functional outcomes were assessed using the modified Rankin Scale (mRS) at 90 days; dichotomized into good (mRS 0-3) and poor (mRS 4-6) outcomes. Demographic data, clinical characteristics, procedural variables, and imaging findings were compared between the groups using pairwise comparisons and multivariable logistic regression models to identify predictors of futile recanalization. Results: Among the 163 patients who qualified for final analysis, 73 (44.8%) had good functional outcomes, while 90 (55.2%) had poor outcomes despite successful recanalization. Age (72 years vs. 64 years, p=0.0014), baseline NIHSS score (22 vs. 14, p<0.0001), and serum glucose levels (142 mg/dL vs. 124 mg/dL, p=0.0109) were significantly higher in patients with poor outcomes. In addition, intubation (57.1% vs. 25.4%, p<0.001) and prior history of diabetes mellitus (34.4% vs. 17.8%, p=0.017) and coronary artery disease (33.3% vs. 16.4%, p=0.014) were more prevalent in the poor outcome group. Multivariable analysis confirmed that advanced age (OR 0.73, 95% CI: 0.57-0.93, p=0.012), higher serum glucose (OR 0.90, 95% CI: 0.82-0.99, p=0.025), NIHSS at 24-36 hours post-last known well (OR 0.61, 95% CI: 0.38-0.98, p=0.039), and mRS at discharge (OR 0.0001, 95% CI: 0.0002-0.064, p=0.005) were independent predictors of poor functional outcomes, indicating futile recanalization. A subgroup analysis of patients with complete recanalization (mTICI 2c/3) further validated these findings. Conclusion: Futile recanalization after EVT for VBAO is linked to older age, elevated serum glucose levels, higher NIHSS scores at 24-36 hours, and poor mRS at discharge. These factors should be carefully considered in clinical decision-making to improve patient selection for EVT in VBAO.