Better Way to Avoid Artery Reclog?

Study Looks at Drug-Coated Angioplasty Balloons as Alternative to Drug-Coated Stents in Heart

From the WebMD Archives

Nov. 15, 2006 (Chicago) - Researchers have come up with a way to keep heart arteries from reclogging after doctors use a tiny angioplasty balloon to open them: Coat the balloons with drugs.

In a study of 52 people, using a drug-coated balloon significantly cut the chance of artery reclogging, says researcher Bruno Scheller, MD, of Saarland University in Homburg, Germany.

The findings were met with enthusiasm by U.S. researchers at the American Heart Association (AHA) meeting here.

Only hours before they heard conflicting reports about the long-term safety of drug-coated stents - another device used for clogged arteries.

Since first approved for use in the U.S. in 2003, drug-coated stents -- also called drug-eluting stents -- have been embraced as the best way to prevent reclogging of the artery.

The new study suggests using a coated balloon may be a better option.

"These are very encouraging results," says past AHA President Sidney C. Smith Jr., MD. Smith is a heart specialist at the University of North Carolina in Chapel Hill.

"With drug-coated stents, [reclogging] is less of a problem, but it's still a problem," he tells WebMD.

Add to that the fact that some new studies suggest drug-coated stents may carry a delayed risk of dangerous blood clots, and there's a tremendous need for new options, Smith says.

From Angioplasty to Stents and Beyond

Angioplasty is used in more than a third of people with heart disease.

With simple angioplasty, a balloon at the end of a long tube is threaded through an artery in the groin.

The doctor guides the tube up the artery and into the heart, inflating the balloon where the vessel has narrowed.

The balloon opens up the walls of the vessel. Then it is deflated and removed.

But in about 25% or 30% of patients, the arteries close up again.

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Adding a Stent

To keep the vessel open, doctors often install a stent after deflating the balloon. The metal, mesh-like tube props open the clogged artery and restores blood flow.

Stents bring the rate of renarrowing down to about 15% to 25%.

In recent years, stents coated with drugs to reduce buildup of scar tissue have become increasingly popular.

They appear to provide additional protection against reblockage and now account for up to 90% of all stent placements in the U.S.

Research has shown these drug-coated stents can lower the risk of heart attack and reduce the need for repeat surgeries to clear clogged arteries.

Drug-Coated Angioplasty Better?

But these stents aren't perfect. The new study presented here looked at people who developed restenosis, or reclogging of the artery, after getting a drug-coated stent.

After the reclogging, 23 people got simple angioplasty with an uncoated balloon. Twenty-two more got angioplasty with the new drug-coated balloon. None received new stents.

Over the following 12 months, arteries reclogged in 10 of those treated with the uncoated balloons.

In contrast, just one person who had a drug-coated balloon developed restenosis.

The bottom line: Just one person treated with a coated balloon needed a repeat procedure to open reclogged arteries, had a heart attack or stroke, or died; compared with eight people in the uncoated balloon group.

Smith says the fact that the coated balloons helped people who already had restenosis "makes the findings even more promising, although they need to be confirmed in a larger study."

Drug-Coated Stents Debate

Other research presented at the meeting set off a lively debate about the long-term safety of drug-coated stents.

Among the conflicting research:

  • A study of more than 9,000 people found those who got drug-coated stents were significantly more likely to die in the three years after the procedure, compared with those treated with bare metal stents. "Given the dominance of drug-eluting stents in current practice, we think these findings raise concern," says researcher Joseph B. Muhlestein, MD, professor of medicine at the University of Utah in Salt Lake City. "Further study is needed."

  • In a study of more than 3,000 people fitted with either bare metal stents or drug-coated stents, risk of having a blood clot, heart attack, or other adverse event was similar in both groups after one year. And those who got drug-coated stents were less likely to need another angioplasty or bypass surgery. "There is no evidence to support abandoning the routine use of drug-eluting stents," says researcher David Williams, MD, professor of medicine at Brown University Medical School in Providence, R.I.

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Antiplatelet Therapy Stressed

None of the researchers is calling for an end to the use of drug-coated stents. But well-designed studies comparing the safety of bare stents and drug-coated stents are needed, they say.

In the meantime, researchers say, it might be best to continue antiplatelet therapy for at least a year after inserting a stent -- maybe longer.

The reason? Any added risk of heart attack or death in people fitted with drug-coated stents is thought to be due to an increased risk of blood clots. Antiplatelet therapy with aspirin and Plavix reduces the risk of clots.

Too many people stop taking the drugs earlier than they should, usually due to excess bruising or expense, Smith says. Plavix costs more than $135 a month.

"People don't understand how important it is to take the drugs for as long as their cardiologist advises," Smith says.

WebMD Health News Reviewed by Louise Chang, MD on November 15, 2006

Sources

SOURCES: American Heart Association's Scientific Sessions 2006, Chicago, Nov. 12-15, 2006. Bruno Scheller, MD, Saarland University, Homburg, Germany. Sidney C. Smith Jr., MD, past president, American Heart Association; professor of medicine, University of North Carolina, Chapel Hill. Joseph B. Muhlestein, MD, professor of medicine, University of Utah, Salt Lake City. David Williams, MD, professor of medicine, Brown University Medical School, Providence, R.I. Scheller, B. The New England Journal of Medicine, Nov. 16, 2006; vol 355: pages 2113-2124 (Early release on Nov. 13, 2006).

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