Stent-assisted angioplasty of symptomatic intracranial vertebrobasilar artery stenosis: feasibility and follow-up results

BACKGROUND AND PURPOSE: The natural history of symptomatic, untreated posterior circulation stenosis is dismal, with many patients experiencing significant morbidity or mortality. The purpose of this study was to evaluate the feasibility and results of stent-assisted angioplasty of symptomatic intracranial vertebrobasilar artery stenosis.METHODS: We reviewed the imaging findings and medical records of 17 consecutive patients who were treated with stent-assisted angioplasty for medically refractory vertebrobasilar artery stenosis. The location of the lesion, degree of stenosis, procedure-related complications, and clinical and short- and long-term angiographic results were assessed.RESULTS: The population included 17 cases (10 men, seven women; age range, 51–74 years; mean, 64 years). The locations of the lesions were intracranial vertebral artery (n = 13) and basilar artery (n = 6). The mean degree of stenosis decreased from 76.1 ± 14.6% before stent-assisted angioplasty to 1.3 ± 2.8% (P < .05) after the procedure. Acute in-stent thrombosis developed in one case (6%, Mori type B lesion), which was successfully treated with intraarterial abciximab infusion and angioplasty. Another patient (6%, Mori type C lesion) developed immediate postprocedural transient diplopia and ataxia, which gradually resolved. No other patient showed symptoms related to the vertebrobasilar artery lesion at follow-up. No significant restenosis was observed at short-term (five patients; follow-up range, 0.5–6 months; mean, 4.3 months) or long-term (six patients; follow-up range, 12–41 months; mean, 21 months) angiographic follow-up.CONCLUSION: Stent-assisted angioplasty is a feasible treatment method for vertebrobasilar artery stenosis. The patency of the stent-assisted angioplasty seems to be preserved in the long-term, with good clinical outcome.

The natural history of untreated posterior circulation stenosis is dismal, with many patients experiencing significant morbidity or mortality (1–3). Retrospective data suggest that the annual stroke rates for patients with symptomatic intracranial vertebral or basilar artery stenosis are 7.8% and 10.7%, respectively, despite anticoagulation or antiplatelet therapy (3).Recently, percutaneous transluminal angioplasty was proposed as a promising alternative treatment for patients with intracranial atherosclerotic stenosis symptoms despite medical therapy. However, percutaneous transluminal angioplasty has had the problems of dissection, elastic recoil, and thrombosis (4, 5). In a series of 42 cases of angioplasty for intracranial stenosis by Mori et al (4), the 1-year angiographic restenosis rate in type A (short, ≤5 mm in length, concentric or moderately eccentric lesions not totally occlusive), type B (tubular, 5–10 mm in length, extremely eccentric or totally occluded lesions, <3 months old), and type C (diffuse, >10 mm in length, extremely angulated [>90°] lesions with excessive tortuosity of the proximal segment, or totally occluded lesions, and ≥3 months old) lesions were 0%, 33%, and 100%, respectively, with cumulative risk of fatal or nonfatal ipsilateral ischemic stroke in 8%, 12%, 56%, respectively, at 1 and 2 years.Stent-assisted angioplasty has been limited mainly by the apprehension concerning the technical feasibility, periprocedural complications, and short- and long-term outcomes (6). Major problems still exist; nonetheless, recent technical advances in instruments used for angioplasty and stent placement have allowed easier trackability through the small and tortuous intracranial vessels. Also, experience from the earlier works of intracranial angioplasty and stent placement has allowed a relatively safe procedure with fewer periprocedural complications (7–14).We reviewed our experience with stent-assisted angioplasty for medically refractory intracranial vertebral and basilar artery stenoses, including the intra- and periprocedural complications and long-term angiographic and clinical outcomes.