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

Abstract

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.

Fig 1.

Representative case of multistaged balloon inflation technique in a patient with left distal vertebral artery stenosis. A, Pretreament angiogram shows a severely stenosed left distal vertebral artery at the site of posterior inferior cerebellar artery. B, Angiogram shows the stent placed at the targeted lesion site; slow subnominal inflation (5 atm in this case) of the balloon was performed, with special consideration given to preventing “dog boning” of the proximal and distal ends of the balloon. Angiogram (not shown) was obtained to confirm the absence of a gap at the distal end of the stent. C, Angiogram shows the balloon is carefully retrieved, with the proximal balloon marker (dotted arrow) placed outside the struts of the proximal end of the stent (solid arrow). D, The balloon was slowly inflated to or above the nominal pressure, with special consideration given to avoiding any gap in the middle and proximal aspects of the stents. Repeat inflations were performed if any gap was visualized on the angiogram. E, Final angiogram shows a well-positioned stent without gaps.

Fig 2.

Case 8. A 55-year-old man with transient ischemic attack at presentation. A, Initial left vertebral artery angiogram shows 95% stenosis of the intracranial vertebral artery. B, Angiogram shows that the distal vertebral artery is straightened because of the stent-mounted catheter, and the lesion site is displaced more cranially (arrow). Primary stent deployment was attempted with a S660 2.5/9 stent; however, the distal end of the stent could not pass through the lesion site. Stent catheter was not retrieved because of concerns for acute thrombus formation. Notice the compromised flow in the basilar artery due to the trapped stent catheter. C, Magnified angiographic view. After deployment of the initial stent (solid arrows) and additional careful angioplasty, a second stent-mounted catheter (dotted arrows) was navigated through the initial stent. D, Magnified angiographic view. The second stent (dotted arrows) was deployed partially overlapping the initial stent (solid arrows) and covering the distal aspect of the lesion. E, Final angiogram shows no residual stenosis. F, Seventeen-month follow-up angiogram shows the patent stent site without significant restenosis.