Treatment of proximal segment stenoses of vertebral arteries with baloon expandable silicon carbide coated stents

Abstract

Background: Untreated atherosclerotic stenotic lesions of the vertebral arteries may result in signs of vertebro-basilar syndrome, transient ischemic attacks or a permanent neurologic deficit of the brainstem and cerebellum. Stenting of the vertebral artery origin (V1 segment), most frequently involved part of the artery, represents a newer treatment option in the endovascular management of occlusive atherosclerotic vascular disease in the posterior circulation. The method is more effective than percutaneous angioplasty, due to a lower restenosis rate. Material and methods: With respect to the trial inclusion criteria, we treated 23 patients with symptoms of vertebro-basilar syndrome due to hemodynamically significant stenosis of V1 segment. The patients included in the study were treated from April 2009 until August 2011. Diagnostic workout and control angiography were performed by multislice computed tomography angiography of both vertebral and basilar artery. The lesions were treated with balloon expandable, silicon carbide coated nitinol stents. All patients received continuous antithrombotic and anticoagulant protection with acetylsalicylic acid and clopidogrel before and after the procedure. All patients underwent control neurological and CT angiography examination six to twelve months after the procedure. Results: In the treated patients, the degree of stenosis of dominant vertebral artery ranged from 50 % to 93 %. Stenting was performed in all patients without distal filter protection. There were no peri-procedural adverse events. Control CT angiography showed one stent occlusion and one greater hemodynamically significant restenosis over 50 %, other stents we patent. None of the patients, not even those with occluded stents, presented with worsening of symptoms or a worse outcome on the Ranking scale at the time of control neurological examination. Conclusions: Stenting of the vertebral arteries can significantly improve hemodynamic conditions in the posterior circulation and prevent recurrent transient ischemic attacks and worsening of vertebro-basilar symptoms. So far, less than twenty studies have been published on the stenting of vertebral arteries worldwide. Randomized larger prospective trials are needed to confirm the benefit of endovascular treatment of vertebral artery stenosis, also by use of drugeluting stents.