Stents are inserted by collapsing them to a small diameter and placing them over a balloon catheter, according to the American Heart Association. When the balloon is inflated in a blocked artery, the stent expands, locks in place and forms a scaffold that holds the artery open.
The stent stays in the artery permanently, keeping blood flowing and relieving symptoms like chest pain. Within a few weeks of the procedure, the inside lining of the artery grows over the metal surface of the stent.
For patients whose arteries are clogged with plaque, the procedure is a simple one that usually takes a few hours, according to the U.S. National Institutes of Health. They are awake during the procedure but under sedation, and generally the only sensation felt is when the balloon is expanded to push the stent into place.
Drug-coated stents are recommended particularly for patients with an increased risk of suffering from reclosure, Tu said. These patients include people with diabetes and people with smaller-than-normal blood vessels or long lesions left by their heart disease.
"Those are the patients who seem to derive the most benefit," Tu said.
The drug-coated stents have been quite successful in preventing the need for repeat procedures, Mauri said.
"The coated stents have medication on them," she said. "The medicine releases slowly over time and prevents cells from building up that could lead to a blockage."
Tu and Mauri have both conducted large studies showing that the drug-coated stents can be as safe as the bare metal ones that preceded them.
However, even proponents of drug-coated stents note that they have their risks, mainly involving the medications that must be taken with them.
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