WEDNESDAY, Sept. 7 (HealthDay News) -- Stroke patients who receive aggressive medical therapy have a better chance of avoiding a second stroke than those who receive medical therapy plus a stent in the brain, a new study reveals.

The difference is so significant that a trial was stopped early because data showed patients who received stents died more often and had more strokes than those treated with medical therapy alone.

"We hypothesized that stenting would be more effective than medical therapy and found exactly the opposite," said lead researcher Dr. Marc I. Chimowitz, a professor of neurology at the Medical University of South Carolina.

"In this population, given the results of the study, I would recommend aggressive medical management," he said.

There may be a place for stenting in patients who don't respond well to medical therapy alone, Chimowitz added. However, he has stopped doing the procedure since seeing the results of this trial, called the Stenting and Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis (SAMMPRIS) study.

The report was published in the Sept. 7 online edition of the New England Journal of Medicine.

For this trial, researchers randomly assigned 451 stroke patients to aggressive medical treatment or medical treatment plus a brain stent. The researchers anticipated that stenting would reduce the risk of recurrent stroke or death by 35 percent over two years.

The patients were between 30 and 80 years old and in the highest risk category for stroke, with blockage or narrowing of arteries of 70 to 99 percent. Most patients with less severe blockage receive medical therapy alone as a matter of course, the researchers noted.

Among those receiving stents, 14.7 percent died or had a stroke within a month after treatment, compared with 5.8 percent of those who received medical therapy alone, the researchers found.

Over less than a year of follow-up, 20.5 percent of the stented patients died or had a stroke, compared with 11.5 percent of those receiving medical therapy alone, they added.

Based on these numbers, the study's data and safety monitoring board recommended stopping new enrollment, and the U.S. National Institutes of Health, which funded the study, issued a clinical alert. Patients still in the trial will continue to be followed for another two years, the agency said.

Medical therapy included the blood thinners Plavix (clopidogrel) and aspirin to reduce the risk of clots, plus blood pressure and cholesterol medications. Patients also took part in a lifestyle modification program that focused on quitting smoking, increasing exercise and controlling diabetes and cholesterol.

Stenting involves placing a tiny metal mesh tube in an artery to help keep it open. This method is commonly used in heart and leg arteries. However, stent placement in the brain can dislodge plaque, causing the artery to become blocked. In addition, the procedure can damage an artery, causing excessive bleeding.

The system used in the trial -- the Gateway-Wingspan intracranial angioplasty and stenting system, made by Stryker Corp. -- is the only system approved by the U.S. Food and Drug Administration (FDA) for certain high-risk stroke patients. Similar systems, not FDA-approved, are being used, but were not included in this trial, the researchers noted.

Despite these findings, Stryker still stands behind its product. "Stryker continues to support the Wingspan Stent System as an FDA-approved Humanitarian Use Device for improving cerebral artery lumen diameter in patients with intracranial atherosclerotic disease who have failed medical therapy," the company said in a statement Wednesday.

"The SAMMPRIS trial was focused on the treatment of severe intracranial atherosclerotic disease, earlier in the treatment lifecycle and with a more aggressive drug treatment regimen than is used in standard practice today," the Fremont, Calif.-based company added.

Dr. Joseph Broderick, the Albert Barnes Voorheis Chair of Neurology at the University of Cincinnati and author of an accompany journal editorial, said that "at this point using mechanical devices to prevent strokes is not better than aggressive medical treatment."

Stenting may have a place for those patients who do not respond to medical therapy. "But there is also a higher risk," Broderick said.

Given the results of this trial, insurers may not reimburse doctors for this procedure, Broderick noted. The findings will likely greatly reduce the number of these procedures, he added.

Another expert, Dr. Larry B. Goldstein, director of the Duke University Stroke Center, said that "SAMMPRIS is consistent with other studies showing that current aggressive medical therapy is associated with considerably lower stroke rates than have been found in the past."

Goldstein added, "It also underscores the need for adequately controlled studies of new interventions. The use of expectations based on historic data can lead to incorrect and potentially dangerous conclusions."

More information

For more information on stroke, visit the American Stroke Association.