Outcome and recanalization rate of tandem basilar artery occlusion treated by mechanical thrombectomy

Abstract

Background: Tandem basilar artery occlusions (tBAO) are defined as concomitant basilar artery and extracranial dominant vertebral artery occlusions. The prognosis of such tBAO treated by mechanical thrombectomy (MT) has been scantly reported. The purpose of our study was to compare the safety and effectiveness of MT for patients with tBAO compared to those with non-tandem basilar artery occlusions (ntBAO).

Patients and methods: Retrospective analysis of a database of patients who underwent MT at two academic centres. All patients treated for BAO were retrieved. Patients with tBAO, defined as a concomitant BAO and extracranial vertebral artery (VA) occlusion or severe stenosis ≥70% (V1 or proximal V2 segment) were compared with patients with ntBAO.

Results: A total of 15 patients with tBAO and 74 patients with ntBAO were enrolled. Successful reperfusion (modified thrombolysis in cerebral infarction score ≥2b) was obtained in 73.3% versus 90.5% (OR = 0.29, 95%CI: 0.07-1.15), good clinical outcome (3-months modified Rankin scale ≤2) was reached by 26.7% versus 32.4% (OR = 0.76; 95% CI: 0.24-2.63) and mortality at 3-months was 46.7% versus 31% (OR = 1.94; 95%CI: 0.63-6) of patients with tBAO versus ntBAO, respectively. Two patients (13.3%) with tBAO and three (4%) with ntBAO had symptomatic intracranial haemorrhage (OR = 3.64; 95% CI: 0.55-24).

Conclusion: Mechanical thrombectomy for patients with tandem basilar artery occlusion tends to be associated with lower rates of successful reperfusion and good clinical outcome, and higher rate of mortality. Larger multicentre studies are warranted to better precise the proper selection and management of such patients.

Keywords: Basilar artery occlusion; Mechanical thrombectomy; Outcome; Recanalization; Tandem; Vertebral artery occlusion.