The VISSIT study has shown that among patients with symptomatic intracranial arterial stenosis, the use of a balloon-expandable stent compared with medical therapy (clopidogrel and aspirin) resulted in an increase of stroke or transient ischaemic attack. The study was published in the 24/31 March issue of the Journal of the American Medical Association (JAMA).
Intracranial arterial stenosis is a common cause of stroke worldwide. The recurrent stroke risk with severe symptomatic intracranial stenosis may be as high as 23% at one year, despite medical therapy, according to background information in the study.
Osama O Zaidat of the Medical College of Wisconsin/Froedtert Hospital, Milwaukee, USA and colleagues randomly assigned 112 patients with symptomatic intracranial stenosis (narrowing of 70% or greater) to receive a balloon-expandable stent plus medical therapy (stent group; n=59) or medical therapy alone (medical group; n=53). Medical therapy consisted of clopidogrel (75mg daily) for the first three months after enrolment and aspirin (81-325mg daily) for the study duration. This international trial, with sites in the United States, China and Europe, enrolled patients from 27 sites (January 2009–June 2012) with last follow-up in May 2013.
Enrolment was halted by the sponsor after negative results from a similar trial (SAMMPRIS) prompted an early analysis of outcomes, which suggested futility after 112 patients of a planned sample size of 250 were enrolled.
The 30-day safety endpoint of any stroke within 30 days or hard transient ischaemic attack (defined as a transient episode of neurological dysfunction caused by focal brain or retinal ischaemia lasting at least 10 minutes but resolving within 24 hours) within two to 30 days was 9.4% (5/53) in the medical group and 24.1% (14/58) in the stent group. Ischaemic stroke was observed in three patients (5.7%) in the medical group and in 10 patients (17.2%) in the stent group. Intracranial haemorrhage occurred in five patients (8.6%) in the stent group and in zero in the medical group. The one-year outcome of stroke or hard transient ischaemic attack occurred in more patients in the stent group (36.2%) vs the medical group (15.1%).
Thirty day all-cause death was three of 58 patients (5.2%) in the stent group and zero in the medical group. A measure of disability worsened in more patients in the stent group than in the medical group.
“These findings do not support the use of a balloon-expandable stent for patients with intracranial arterial stenosis,” the authors conclude.
In an accompanying editorial (Endovascular therapy for atherosclerotic intracranial arterial stenosis—Back to the drawing board), Marc I Chimowitz of the Medical University of South Carolina, Charleston, and Colin P Derdeyn of the Washington University School of Medicine, St Louis, both USA, state: “For endovascular therapy (eg., angioplasty alone or new stents) to have any role, multicentre pilot studies will be required to establish the safety and potential efficacy of these devices in carefully defined patient populations. Given the disappointing performance of intracranial stenting in both VISSIT and SAMMPRIS, it is difficult to foresee how these necessary steps will happen anytime soon.”