Stroke Prevention Trial Has Immediate Implications for Treating Patients

Newswise — People who received intensive medical treatment following a first stroke had fewer second episodes and were less likely to die than people who received brain stents in addition to medical treatment, according to a new report in the New England Journal of Medicine, to be published online Sept. 7. All patients in the study had experienced one stroke and were considered at high risk for a second one.

Two co-authors on the paper were Methodist Neurological Institute investigators involved in the NIH-funded trial - Dr. David Chiu, principal investigator and medical director of Methodist’s Eddy Scurlock Stroke Center, and Dr. Richard Klucznik, co-investigator and interventional neuro-radiologist.

“This study is important because it will impact the way we treat stroke patients with arterial blockage in the brain,” said Chiu. “Over the past several years, we have improved treatments for intracranial atherosclerosis, and this research shows that intensive medical management is the key to preventing stroke recurrence.”

The Stenting vs. Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis (SAMMPRIS) study enrolled more than 450 patients at 50 sites across the United States

Co-authors say stroke patients with recent symptoms and intracranial arterial blockage of 70 percent or greater should be treated with an aggressive medical therapy that mirrors the regimen used in this trial. The regimen used in the study included daily blood-thinning medications and the aggressive control of blood pressure and cholesterol.

The Methodist Neurological Institute had the fourth largest patient enrollment nationwide (20). New enrollment in the study was stopped in April because early data showed significantly more strokes and deaths occurred among the stented patients at the 30-day mark compared to the group who received the medical management alone. All patients will continue to be followed for two years to determine the long term effects of both interventions.

In addition to the intensive medical program, half of the patients in the study received an intervention of a self-expanding stent called a Gateway-Wingspan that widens a major artery in the brain and facilitates blood flow. The study patients at Methodist who received a stent (10) suffered no complications from stenting.

“One possible explanation for the higher stroke rate in the overall stented group is that patients who have had recent stroke symptoms sometimes have unstable plaque in their arteries which the stent could have dislodged,” said Dr. Richard Klucznik, interventional neuro-radiologist at Methodist and co-author on the paper.

Stroke is the fourth leading cause of death in the United States. Stenosis, a blockage or narrowing of brain arteries caused by the build-up of plaque, accounts for more than 50,000 of the 795,000 strokes that occur annually nationwide. Stenosis is particularly common in African-Americans, Hispanics, Asian-Americans and people with diabetes.

SAMMPRIS is the first stroke prevention trial to compare intracranial stenting with medical therapy and to incorporate intensive medical management into the study design. This includes a daily dosage of 325 mg aspirin; 75 mg clopidogrel, a medication used to prevent blood clots, for 90 days after enrollment; and aggressive management of key stroke risk factors – high blood pressure and high levels of low density lipoprotein (LDL), the unhealthy form of cholesterol. All patients also participated in a lifestyle modification program that focused on quitting smoking, increasing exercise, and controlling diabetes and cholesterol.

The National Institute of Neurological Disorders and Stroke (NINDS), part of the National Institutes of Health, funded the trial.

Reference: Chimowitz MI, Lynn, MJ, Derdeyn CP, Turan TN, Fiorella D, Lane, BF, Janis, S, Lutsep HL, Barnwell SL, Waters MF, Hoh BL, Hourihane JM, Levy EI, Alexandrov AV, Harrigan MR, Chiu D, Klucznik R, Clark JM, McDougall CG, Johnson, MD, Pride, GL, Torbey MT, Zaidat OO, Rumboldt Z, Cloft HJ, for the Stenting and Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis Trial Investigators. “Stenting Versus Aggressive Medical Therapy for Intracranial Artery Stenosis.” New England Journal of Medicine, published online September 7, 2011.

For more on the Methodist’s stroke program, visit www.methodisthealth.com/stroke or call 713-790-3333. Follow us on Twitter at http://twitter.com/MethodistHosp and Facebook at http://www.facebook.com/methodisthospital.

About the SAMMPRIS study

The SAMMPRIS study enrolled 451 patients at 50 sites across the United States. Patients were between 30 and 80 years old and had experienced a recent transient ischemic attack, a type of stroke that resolves within 24 hours, or another type of non-disabling stroke, which was caused by a large degree of stenosis in a cerebral artery. The investigators looked at whether patients had a second stroke or died within 30 days of enrollment, or had a stroke in the same area of the brain from 30 days to the end of follow-up. They had hypothesized that compared to intensive medical therapy alone; the addition of an intracranial stenting system would decrease the risk of a stroke or death by 35 percent over two years.

Instead they found that 14.7 percent of patients (33) in the stenting group experienced a stroke or died within the first 30 days after enrollment, compared with 5.8 percent (13) of patients treated with medical therapy alone. There were five stroke-related deaths within 30 days, all in the stenting group, and one non-stroke-related death in the medical management group. During a follow-up period of just less than one year, 20.5 percent of patients in the stenting group and 11.5 percent of patients in the medical group had a stroke or death, or a stroke in the same area of the brain beyond 30 days, a highly significant difference in favor of the patients in the study’s medical group.

The authors emphasize that the study participants were in the highest risk category, with blockage or narrowing of arteries of 70 to 99 percent. Stroke patients with moderate cerebral arterial blockage (50-69 percent) were excluded because their risk of stroke is low with usual medical management, and researchers thought this group would be unlikely to benefit from stenting.