Symptomatic Atherosclerotic Non-acute Intracranial Vertebral Artery Total Occlusion: Clinical Features, Imaging Characteristics, Endovascular Recanalization, and Follow-up Outcomes

Background and Objectives: Previous studies on symptomatic atherosclerotic non-acute intracranial vertebral artery total occlusion that was refractory to medical therapy are rare. We aimed to assess the clinical features, imaging characteristics, endovascular treatment feasibility and follow-up outcomes of patients with this condition. Methods: Data from consecutive patients who had symptomatic atherosclerotic non-acute intracranial vertebral artery total occlusion and underwent endovascular recanalization from February 2016 to April 2020 were retrospectively collected in our prospective database. Clinical, imaging, procedural, and follow-up data were collected and analyzed. Results: Thirty-one patients, predominantly males, were enrolled in this study. These patients presented with recurrent/progressive stroke in the posterior circulation despite aggressive medical therapy. Angiographic analysis revealed asymmetric vertebral arteries due to unilateral hypoplasia and intracranial vertebral artery total occlusions in the dominant vertebral arteries, which were characterized by long lesion length and high clot burden. Multiple infarctions and perfusion defects in the posterior circulation were demonstrated by diffusion-weighted imaging and arterial spin labeling, respectively. Successful endovascular recanalization was achieved in 87.1% of the patients. Over a median clinical follow-up duration of 11.0 months, 74.1% of patients with successful recanalization achieved favorable clinical outcomes (mRS score ≤2). Conclusion: Symptomatic atherosclerotic non-acute intracranial vertebral artery total occlusion attributable to hypoperfusion is characterized by recurrent/progressive ischemic events, dominant intracranial vertebral artery total occlusion, long lesion length, and high clot burden. Endovascular recanalization of the dominant intracranial vertebral artery occlusion appears to be a feasible treatment for these patients.