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How do coronary stents work?

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Coronary stentFormer President Bill Clinton received two stents in one of his coronary arteries Thursday at a New York City hospital, according to a prepared statement by his adviser Douglas Band. Clinton, who underwent a quadruple bypass in 2004, left New York–Presbyterian Hospital on Friday.

Coronary stents are mesh scaffolds that are threaded into arteries and then expanded, usually by inflating a balloon inside the stent, to hold a previously plaque-clogged vessel open. Stents are often employed following angioplasty, in which an unstented balloon is first inflated to widen a clogged or narrowed artery; the stent is then inserted and expanded by another balloon to keep the vessel from renarrowing. Direct stenting [above] opens the artery and implants the stent in one step.

A 2007 study in The New England Journal of Medicine cast doubt on the benefits of stents in typical heart-disease patients, but stenting remains a common medical procedure. According to The Wall Street Journal, about one million stents are implanted in the U.S. each year.

For more on stents, see "Expanding Use," from the July 2006 issue of Scientific American.

Illustration: Ken Eward/BioGrafx

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  1. 1. ope 1:50 pm 02/16/2010

    is it possible for these stents to come out or slip out?

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  2. 2. LGR 5:57 pm 02/16/2010

    There is growing evidence that a high-quality l-arginine/l-citrulline combination supplement will help clear vessels of plaque. Certainly worth trying in light of the repeat nature of inserting stents!

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  3. 3. JazzR894 10:22 am 02/17/2010

    Stents seem very interesting, but also painful. When you undergo this procedure are you able to feel the stents inside of your body after recovery? Is it painful to have inside of you?

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  4. 4. Rosmery Fernandez 1:00 pm 02/26/2010

    This is a process that was done to one of my family members ans it is extremely beneficial, but can these stents break?

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  5. 5. spacelunatic 2:12 pm 02/27/2010

    Nope i don’t feel anything. Not painful at all. I’m a believer in stents helpfulness, i have 5 and they have saved my life. Had 2 heart attacks, earliest was at 38, I’m 51 now and feel great. Of course that could change and unless they come out with a a way to clear plaque, i will likely have a bypass in the not too distant future.

    FYI: I’m only about 15-20lbs overweight, not obese at all and I eat much better than the avg American. But sendentary. My body produces cholesterol much easier than normal. I need to exercise more.

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  6. 6. LGR 10:06 pm 03/8/2010

    Check out the YouTube video at If you want to learn more about something that DOES help clear plaque by helping your body function normally, contact me at

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  7. 7. haditalldone 10:14 am 03/14/2010

    Some patients can. It is believed that when a stent is pushed too hard against the artery wall, it can cause discomfort. Also the plaque (if some has hardened) can damage the artery when squashed against healthy artery tissue. I’ve had 6 stents now but I can’t feel any of them.

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  8. 8. haditalldone 10:16 am 03/14/2010

    Stents can fracture or collapse but this is very rare and happens generally soon after installation.

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  9. 9. haditalldone 10:18 am 03/14/2010

    Not if the cardiologist knows his job. The pressure applied should be sufficient to push it firmly against the artery lining. Then you start to grow new tissue across the stent. In some procedures a stent is ‘lost’ where it detaches from the catheter prematurelly, but again this is very rare indeed.

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