Tuesday, November 14, 2006

Drug-Coated Angioplasty Balloons Keep Arteries From Reclosing

(HealthDay News) -- Coating angioplasty balloons with a drug also used to coat stents prevents arteries from closing over again.

This raises the possibility that drug-eluting stents, or stents covered with sustained-release drugs, might not be needed, a new German study suggests.

The trial was a small one and needs to be replicated, the researchers said. The results of the study are published in the Nov. 16 issue of the New England Journal of Medicine and were released early to coincide with a presentation Monday at the American Heart Association's annual meeting, in Chicago.

Narrowing of an artery -- called stenosis -- is commonly treated with balloon angioplasty and insertion of a stent. Angioplasty is a procedure in which a balloon is used to open narrowed or blocked blood vessels. A stent is a wire, mesh tube that props open an artery.
But the procedure isn't foolproof. According to the study authors, 5 percent to 35 percent of people who receive regular, uncoated stents will still experience restenosis. The percentage is lower for people who receive coated stents.

According to an editorial in the journal, the use of drug-eluting stents has eclipsed other approaches, even though it seems that rates of restenosis even after using drug-eluting stents are higher than initially thought.

For the new study, the researchers wanted to see if using angioplasty balloon catheters coated with paclitaxel worked for the treatment of "coronary in-stent restenosis" -- re-narrowing of the artery after a stent has been implanted.

Fifty-two patients were randomly selected to receive either a drug-coated balloon catheter or an uncoated balloon catheter during coronary angioplasty.

After six months, 10 of 23 patients (43 percent) in the uncoated group experienced restenosis, compared with one of 22 patients (5 percent) in the coated group. At the end of one year, the rate of major adverse cardiac events was 31 percent in the uncoated group, compared to only 4 percent in the coated group.

The effectiveness of the drug-coated balloons was similar to results recently reported for drug-eluting stents in the treatment of in-stent restenosis.

Unlike drug-coated stents, which contain low doses of time-released drugs, drug-eluting balloons are in contact with the artery wall for about one minute and release most of the drug immediately.

Dr. Sidney Smith Jr., past president of the AHA and professor of medicine and director of the Center for Cardiovascular Science and Medicine at the University of North Carolina at Chapel Hill, called the new study results "very interesting and very promising, but with a small number of patients. We have to see if the results can be extended in randomized trials."

Smith also pointed out that the trial look at restenosis, not stenosis, meaning this was not the first time around for the participants.

More information
To learn more about angioplasty, visit the American Heart Association.

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