A Single-Center Experience of Endovascular Treatment in Subtypes of Basilar Artery Occlusion: Embolization Caused by Tandem Vertebral Artery Stenosis May Be Associated with Better Outcomes

-OBJECTIVE: Basilar artery occlusion (BAO) is a severe condition with high mortality. However, surgical proced -res and outcomes of BAO with different pathologic subtypes have not been fully clarified. This study compared the surgical procedures and clinical outcomes of mechanical thrombectomy in different subtypes of BAO. -METHODS: Eighty-six patients with acute BAO receiving endovascular treatment between October 2015 and July 2019 were retrospectively analyzed and placed in 3 groups: pure embolism (group 1), arterial-arterial embolism from steno-occlusion of the tandem vertebral artery (group 2), and in situ atherosclerotic thrombosis (group 3). Recanalization rates, procedure times, surgical characteristics, and clinical outcomes were analyzed. -RESULTS: Groups 1, 2, and 3 included 33 (38.4%), 17 (19.8%), and 36 (41.9%) patients, respectively. The overall successful recanalization rate was 95.3%, and the good outcome rate was 61.6%. The procedure time in group 1 was shorter than the time in groups 2 and 3 (P < 0.001). The clinical good outcome rate was higher in group 2 than in group 1 (88.2% vs. 54.5%; P = 0.017). Groups 1 and 3 had similar good outcome rates (54.5% vs. 55.6%; P = 0.933). Twenty-seven patients received stent angioplasty: 10 of 17 in group 2 (58.8%) and 17 of 36 in group 3 (47.2%). -CONCLUSIONS: The outcome of endovascular treatment for BAO varies among patients with different pathologic mechanisms. Patients with embolism from tandem vertebral artery steno-occlusion achieved the best outcomes. Rescue treatment was more common in patients with embolic BAO with tandem vertebral artery steno-occlusion and BAO with in situ atherosclerotic thrombosis.