Background and purpose Acute basilar artery occlusion (BAO) is a devastating disease with a high rate of mortality and morbidity, and early recanalization is crucial to achieve a good prognosis. The best treatment strategy for BAO combined with a proximal stenosis (tandem occlusion) is not yet clear. Our study aimed to evaluate whether and how vertebrobasilar tandem occlusions can be treated effectively and safely compared with isolated BAO.

Materials and methods Fifty-two patients with acute vertebrobasilar occlusive stroke treated with mechanical thrombectomy were identified in a prospective database from March 2010 to September 2016. We retrospectively analysed the clinical, technical, and functional outcomes of the patients.

Results Of the 52 patients, 15 presented with a tandem occlusion, 14 with a single intracranial occlusion due to an underlying stenosis, and 23 with a single embolic BAO. Successful recanalization was achieved in all of the patients with tandem occlusions (modified Thrombolysis in Cranial Infarction 2b/3) and in 35 of 37 patients with a single BAO (with and without stenosis). A favourable outcome was achieved (modified Rankin Scale ≤2) in 8 of the 15 patients with a tandem occlusion compared with 4 of the 14 patients with a single BAO with underlying stenosis and 5 of the 23 patients with isolated embolic BAO (p=0.18).

Conclusions We suggest that endovascular treatment of vertebrobasilar tandem occlusions is safe and feasible, with a high rate of good outcome.