The first drug-coated stent, containing the drug sirolimus, was approved in the U.S. in 2003 for treating heart disease, and now a second stent, coated with a different drug, may be able to produce similar results, according to a study in this week's New England Journal of Medicine.
Stents are tiny metal, mesh-like structures that are surgically implanted within an artery to prop open clogged arteries and restore blood flow. But a common problem with the devices is that the arteries frequently become re-clogged due to buildup of scar tissue at the site or other problems.
Drug-coated stents slowly release drugs designed to slow or prevent the growth of scar tissue and reduce the risk of renarrowing of the arteries. Currently, they are being used to treat heart disease.
Testing the Second Drug-Coated Stent
In the study, researchers compared the drug-coated stent to regular stents in more than 1,300 adults who were about to receive a stent to correct previously untreated narrowing of the heart arteries. About half were randomly assigned to receive the paclitaxel-coated stent, and the others received a regular bare-metal stent.
After nine months of follow-up, the results showed that the drug-coated stents significantly reduced the need for repeat operations to correct renarrowing of the heart arteries. For example, a secondary operation to correct renarrowing of the same area of the arteries was required in only 3% of those with the paclitaxel-coated stent vs. 11.3% of those with the regular stent.
In addition, tests revealed evidence of renarrowing of the arteries in 7.9% of those with the paclitaxel-coated stents vs. 26.6% of those with the plain stents.
The risk of heart-related death or heart attack was similar in both groups.
Researchers say the results suggest that future studies should compare the two types of drug-coated stents to evaluate their safety and effectiveness.
In an editorial that accompanies the study, Thomas Lee, MD, of Harvard Medical School, notes that although drug-coated stents might share a similar delivery technology, "their embedded drugs will ultimately determine their efficacy."