New Brain Stent Opens Blocked Arteries

Stents — the small mesh tubes that revolutionized heart care — may offer a new option for tens of thousands of stroke survivors who still have blocked brain arteries despite optimal medical treatment.

So suggests a study of 131 stroke survivors implanted with a novel type of stent designed to prop open severely clogged vessels in the brain.

Results showed that in 97 percent of cases, doctors were able to successfully maneuver the stent deep within the brain, exactly to the area of blockage, then open up the clogged artery.

By three months later, 12 percent of patients treated with the brain stent had had another stroke, experienced a brain bleed, or died.

In comparison, 18 percent of people who get traditional drug therapy with aspirin or blood thinners would be expected to die or have a stroke or brain bleed over the three-month period, says Osama Zaidat, M.D., a stroke researcher at the Medical College of Wisconsin, in Milwaukee.

The device also proved safe, he says.

Zaidat's study was presented at the 2007 International Stroke Conference.

Brain Stent Can Maneuver Delicate Vessels

Blocked brain vessels are a cause of ischemic strokes, the most common type of stroke. They occur when blood flow to an area of the brain is compromised by a blood clot or blockage. This leads to the death of brain cells and to brain damage.

Zaidat says that for years, efforts to maneuver stents into the brain's delicate vessels to open blockages generally failed.

The reason: Doctors were using the same stents they used to open blocked heart arteries, he says.

Designed for the more sturdy blood vessels of the heart, such stents were too thick, stiff, and rigid for narrow arteries deep within the brain, Zaidat tells WebMD.

The new stent, known as Wingspan, is specially designed for the more fragile brain blood vessels. It is made of a flexible metal alloy that permits it to navigate vessels in the brain.

The stent is mounted on a balloon-tipped catheter that is inserted into a leg artery and guided just beyond the brain blockage. The balloon is then inflated just enough to open up the blockage and deploy the stent.

Encouraging Findings

The next step, Zaidat says, is a study pitting brain stenting against optimal drug therapy in stroke victims with blocked brain arteries.

"The data are encouraging," says American Stroke Association spokesman Robert J. Adams, M.D., a neurologist at the Medical College of Georgia in Augusta.

But until such a study is performed — and stenting proves better, or at least equal to drug treatment — it's too soon to adopt it in routine practice, Adams tells WebMD.

SOURCES: International Stroke Conference, San Francisco, Feb. 7-9, 2007. Osama Zaidat, MD, Medical College of Wisconsin, Milwaukee. Robert J. Adams, MD, spokesman, American Stroke Association; department of neurology, Medical College of Georgia, Augusta.