MONDAY, Feb. 4, 2008 (HealthDay News) -- Drug-coated stents are better than the bare-metal kind for treating complex arterial blockages, new research finds.
"There are two messages I would take away from the study," said Dr. Robert J. Applegate, a professor of cardiology at Wake Forest University and lead author of a report in the Feb. 12 issue of the Journal of the American College of Cardiology. "The first is that drug-eluting stents are very effective. They were effective in the kind of patients in the initial trials, with simpler problems. Then their effectiveness was broadened to all patients who underwent stent treatment, even in off-label use. All the benefits present in the early trials are showing in the patients that have these high-risk features."
High-risk factors include diabetes, kidney failure, a recent heart attack and longer blockages, Applegate said. "All of these have been matters of concern about the use of drug-eluting stents. We saw them to be effective in these patients."
The study compared results of 1,285 people with such complications who got drug-coated stents, flexible tubes implanted to keep blood vessels open after the clot-removing procedure called angioplasty and 1,164 people who had bare-metal stents. After two years, the incidence of nonfatal heart attacks or deaths was 29 percent lower for those getting drug-coated stents.
The drug-coated stents were also safer, with the incidence of stent-caused clotting roughly half that seen in the bare-metal stent recipients.
Another study reported in the same issue of the journal was more cautious about the long-term effectiveness of drug-coated stents. The study of 310 people who got stents after heart attacks found that those who got drug-coated stents were better off after a year than those getting bare-metal stents, but that there were worrying indications of a possible higher risk of artery reblockage in the coated-stent group.
Stents have been very much in the news lately, with studies such as one that found equal effectiveness of the two drug-coated stents now available in the American market, one sold by Boston Scientific, the other by Cordis.
That study was funded by the two companies, as was the newly reported Wake Forest study. Applegate said that financing of the study by industry did not affect the results of the research. "They had absolutely no influence on the study design, the acquisition of data, the interpretation of data or the scripting of the manuscript," he said.
Its getting harder to do meaningful medical research in the United States for a variety of reasons, said an accompanying editorial by Dr. Cindy Grines, vice chief of academic affairs at William Beaumont Hospital in Royal Oak, Mich. The somewhat frightening "off-label" designation, which means the U.S. Food and Drug Administration hasn't approved that use, is necessary because of the difficulty of conducting trials in the United States, she explained.
"Eighty percent of the studies now are being done outside the United States," Grines said.
Some of the blame goes to the complex rules imposed by the FDA, she said, but the propensity for people claiming damage to file suits also has a constraining effect.
"There are Web sites with legal advice," Grines said. "So, it is very defensive medicine that people are practicing. A consent form might be 10 pages long to do a simple study, which becomes financially undoable in most institutions. It would be really nice if we could have more ability to do these studies here."
You can learn why and how stents are used from the American Heart Association.