Characteristics and prognosis of acute basilar artery occlusion in minor to moderate stroke and severe stroke after endovascular treatment: A multicenter retrospective study.

OBJECTIVE: We aimed to investigate characteristics and outcomes of patients receiving mechanical thrombectomy (MT) between minor to moderate stroke and severe stroke caused by acute basilar artery occlusion (BAO).

METHODS: We retrospectively reviewed the data of all patients with BAO who underwent MT from three stroke centers between January 2016 and January 2020. The patients were dichotomized as minor to moderate or severe stroke group according to their admission National Institutes of Health Stroke Scale (NIHSS) score <21and ≥21. Patient characteristics, imaging findings, and outcomes were compared between the two groups.

RESULTS: A total of 72 patients were included in this study. The posterior circulation Alberta Stroke Program Early CT Score (PC-ASPECTS) in the minor to moderate stroke patients were significantly higher than that of patients with severe stroke (P = 0.013). The good posterior circulation collateral scores (PC-CS) (6-10) were more commonly found in patients with minor to moderate stroke than in patients with severe stroke (58.14 % vs 10.34 %,P < 0.001). There were similar rates of successful recanalization between the two groups. Patients with minor to moderate stroke had a higher rate of favorable outcomes (mRS score 0-2, 60.47 % vs 20.69 %, P = 0.002) and a lower rate of periprocedural complications (4.65 % vs 31.03 %, P = 0.005) and mortality (4.65 % vs 24.14 %, P = 0.026) at 3 months after MT compared with the patients with severe stroke.

CONCLUSIONS: Acute BAO patients with minor to moderate stroke had better posterior circulation collateral and had better outcomes after MT than those patients with severe stroke.