Using stents to prevent strokes questioned

The increasingly common practice of preventing strokes by using wire mesh stents to prop open neck arteries is much riskier than the traditional method of surgically removing plaque and should be curtailed, according to two large European studies.

Patients receiving the stents were nearly 2 1/2 times as likely to have a stroke or die, French researchers reported today in the New England Journal of Medicine. The results were so clear, the researchers said, that they terminated the study prematurely and stopped using the stents.

In a larger German study reported earlier in October, researchers found a smaller, but statistically significant, increased risk associated with the stents and also called for a halt to their use.

Some American researchers, however, said the findings are in conflict with U.S. studies that showed the stents are safer than surgery.

Researchers on both sides are at a loss to explain why the findings are so different. Most agree, however, that a definitive conclusion may not be available until the completion of other studies, including a large study sponsored by the U.S. National Institutes of Health.

An estimated 700,000 Americans suffer strokes each year, and the largest fraction of them are caused by the buildup of plaque in the carotid arteries that provide blood to the brain.

The gold standard for treatment of the condition is surgery to remove plaque from the blood vessels, a process called “carotid endarterectomy.” About 150,000 of the procedures are performed in the U.S. every year.

Two years ago, the Food and Drug Administration approved new stents designed for use in carotid arteries. Just like the larger stents used in coronary arteries to prevent heart attacks, the new stents compress the plaque and hold the artery open.