Outcomes of Endovascular Treatment for Posterior Circulation Stroke According to the Underlying Pathologic Mechanism: A Retrospective Single-Center Analysis

Objectives. This study investigated the functional outcomes and safety of endovascular treatment in patients with posterior circulation stroke according to whether the underlying mechanism was arterial embolism or intrinsic atherosclerosis. Materials and Methods. A total of 108 consecutive patients with posterior circulation ischemic stroke who received endovascular treatment between January 2018 and December 2021, 58 with arterial embolism and 50 with intrinsic atherosclerosis, were identified. The overall and basilar artery occlusion subgroup analyses were retrospectively conducted between the two study groups using a logistic regression model. Results. The rate of successful reperfusion (modified Thrombolysis in Cerebral Infarction score 2b-3) was comparable in the embolism versus intrinsic group (96.6% versus 90.0%; adjusted odds ratio [aOR] 0.73, 95% confidence interval [CI] 0.01-42.74; P=0.88). There was no significant difference in the frequency of a moderate outcome between the two groups (modified Rankin Scale [mRS] score 0-3: 43.1% versus 58.0%; aOR 0.63, 95% CI 0.15-2.50; P=0.51), frequency of a favorable outcome (mRS 0-2: 39.7% versus 38.0%; aOR 1.59, 95% CI 0.37-6.70; P=0.52), the 90-day mortality rate (34.5% versus 26.0%; aOR 2.31, 95% CI 0.50-10.63; P=0.28), or frequency of symptomatic intracranial hemorrhage (6.9% versus 2.0%, respectively; P=0.37). The subgroup analysis in patients with basilar artery occlusion found no significant between-group difference in any of the abovementioned clinical outcomes (all P>0.05). Conclusion. This study indicated that the mechanism of posterior circulation stroke had no significant effect on the functional outcomes after endovascular treatment or on procedural safety.