For symptomatic intracranial stenosis, aggressive medical therapy appears the best choice. Again. According to the findings from VISSIT, patients receiving intracranial stents were more than twice as likely to have a stroke, transient ischemic attack, intracranial hemorrhage or die within the first 30 days.
VISSIT (Vitesse Intracranial Stent Study for Ischemic Stroke Therapy) was assessed and ended early, following the published outcomes of SAMMPRIS (Stenting and Aggressive Medical Therapy for Preventing Recurrent Stroke in Intracranial Stenosis), another trial that compared medical therapy and intracranial stenting. At the time of VISSIT’s closure, 112 patients had been randomized at 20 of 27 international sites. Patients were randomized to either receive medical therapy and a balloon-expandable neurovascular stent or medical therapy alone.
Medical therapy included 75 mg of clopidogrel daily for three months, aspirin for the duration and, dependent on patient factors, statins and antihypertensives.
Stroke and transient ischemic attack (TIA) occurred within 30 days for 9.4 percent and 24.1 percent of medical and stent patients, respectively. Intracranial hemorrhage occurred among 8.6 percent of stent patients, while no medical treatment patients experienced none. At one year, 15.1 percent of medical group patients and 36.2 percent of stent patients had a stroke or TIA.
Osama O. Zaidat, MD, MS, of Medical College of Wisconsin and Froedtert Hospital in Milwaukee, and colleagues wrote that these findings were largely comparable to those of SAMMPRIS. They also noted that, based on the current findings, the likelihood of a successful trial was less than 1 percent had the trial been continued.
The findings of both VISSIT and SAMMPRIS contradict earlier reports of successful balloon-mounted stent trials. However, Zaidat et al noted that these prior studies were not comparable, utilizing different designs, populations and stent types.
Researchers offered several possibilities as to why stents failed to achieve safety margins, including operator inexperience, first-generation devices and potential periprocedural factors that were not controlled.
In an editorial, Marc I. Chimowitz, MBChB, of the Medical University of South Carolina in Charleston, and Colin P. Derdeyn, MD, of the Washington University School of Medicine in St. Louis, commented that the lower than expected stroke rates in the medical treatment group confirm recommendations made on the basis of SAMMPRIS. However, these findings may make future studies into stenting, particularly in high-risk patients, difficult.
“For endovascular therapy (eg, angioplasty alone or new stents) to have any role, multicenter 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 forsee how these necessary steps will happen anytime soon,” they wrote.
The findings were published in the March 24/31 issue of JAMA.