Background and Purpose--The long-term outcome of endovascular intervention compared with best medical management of patients with symptomatic vertebral artery stenosis is uncertain. We therefore compared these treatments in a randomized trial with long-term follow-up.

Methods--In the international, multicenter Carotid And Vertebral Artery Transluminal Angioplasty Study, 16 patients with symptomatic vertebral artery stenosis were randomized in equal proportions to receive endovascular therapy (balloon angioplasty or stenting) or best medical treatment alone. An independent neurologist followed up the patients for as long as 8 years.

Results--Endovascular intervention was technically successful in all 8 patients, but 2 patients experienced transient ischemic attack at the time of endovascular treatment. There were no deaths or strokes in any arterial territory within the first 30 days. During a mean follow-up period of 4.7 years, no patient in either treatment group experienced a vertebrobasilar territory stroke, but 3 patients in each treatment arm died of myocardial infarction or carotid territory stroke, and 1 endovascular patient had a nonfatal carotid territory stroke.

Conclusions--Patients with vertebral artery stenosis were more likely to have carotid territory stroke and myocardial infarction during follow-up than have recurrent vertebrobasilar stroke. The trial failed to show a benefit of endovascular treatment of vertebral artery stenosis, but the numbers of patients included was small. Larger randomized trials are required to determine whether vertebral artery stenting is justified in patients at higher risk of vertebrobasilar stroke. Treatment of patients with vertebral artery stenosis should focus on global reduction of vascular risk, including prevention of carotid territory stroke and myocardial infarction.