Aggressive drugs could be more effective without being combined with an invasive type of surgery to prevent a common type of stroke, a new study has found.

A national clinical trial conducted by researchers at the University of Florida found that patients who used stents, an expensive device used to widen arteritis, were at a much higher risk of the short-term risk of stroke and related death.

Although the short term risks of a stroke were high, the study also found that the artery widening technique that uses balloon angioplasty and stent insertion had favorable results for the long term.

The device was approved by the Food and Drug Administration six years ago on the basis of a humanitarian exemption that did not require solid evidence, the New York Times reported.

This study provides an answer to a long-standing question by physicians -- what to do to prevent a devastating second stroke in a high-risk population, said Dr. Walter Koroshetz, deputy director of NINDS, part of the government's National Institutes of Health, which funded the study.

After finding that the risk of short-term stroke was almost twice as high for patients using stents the researchers said that the study will have a substantial impact on clinical practice and research as it is the first randomized stroke trial to pit stenting against non -surgical treatment for symptomatic intracranial atherosclerosis, a type of stroke caused by artery blockage in the brain.

Every 40 seconds, someone in the U.S. has a stroke. Stroke is the fourth leading cause of death and a leading cause of disability in the U.S. Almost 800,000 people a year have a new or recurring stroke, according to the American Heart Association.

Patients with the type of stroke known as symptomatic intracranial atherosclerosis do not respond well to existing treatments. One-quarter of those patients have another stroke within 12 months, and the risk of additional strokes continues in subsequent years.

The clinical trial that found these results was nicknamed SAMMPRIS and carried out at 50 different sites across the United States.

The study recruited 451 participants age 30 to 80 who had at least 70 percent narrowing in the arteries in the brain, and had experienced symptoms within the previous 30 days.

Patients in one group were randomly assigned to receive intensive management involving smoking cessation and medications for blood pressure, cholesterol, and diabetes and blood-clot prevention.

A second group of patients had that same medical treatment but also had balloon angioplasty and stent implantation into the affected brain artery to improve blood flow.

Researcher initially expected the second group to do better, but the striking difference between the two patient groups prompted the study's independent safety monitoring body to call off new recruitment.

The real question is, is there a benefit to patients over the long term, said study co-author and co-principal investigator Hoh.

If you think about it, when people are concerned about stroke, it's not just their first month that matters, so we're waiting to see what the longer-term results will be, he added.