WEDNESDAY, May 3, 2006 (HealthDay News) -- A new kind of stent did a better job than the artery-opening procedure called angioplasty in improving the walking ability of people with blocked leg arteries, a new European study found.
The use of stents -- small, metal tubes inserted into an artery to hold the blood vessel open -- to treat blocked leg arteries has declined because of problems, such as fracturing of the devices. The medical name for these blockages is peripheral arterial disease (PAD).
But the 51 people in the study who had the new stents implanted in the superficial femoral artery, a major leg blood vessel, were able to walk much further -- the distance of a football field -- than the 53 people who had angioplasty.
The study findings, by physicians at the Medical University of Vienna, appear in the May 4 issue of the New England Journal of Medicine.
The study used two different types of stents made of nitinol, an alloy of nickel and titanium, both made by Guidant Corp., an American company. At least two other U.S. companies are sponsoring tests of stents for leg arteries -- the Cook Corporation, which is using a drug-coated stent; and Cordis, a division of Johnson & Johnson, whose trial of a different nitinol stent is being done in Europe.
Those trials are important for the growing number of older Americans with PAD, the same sort of blood-vessel blockage in the leg that leads to heart attacks and other coronary problems when it occurs in the heart. PAD causes pain and other problems; in the worst cases it can lead to amputation.
The study results probably will help change treatment of PAD in some cases, said Dr. Lawrence Hofmann, chief of interventional radiology at Stanford University School of Medicine.
"My biggest problem over the past two years has been having good scientific data to justify putting in a stent," Hofmann said. "They cost $1,000 each, and some people need two or three."
But the trial was not an unalloyed success, he said. While those people who got stents were able to walk farther both six months and one year after the implants, the rate at which PAD worsened and the need for further intervention was the same as for people who had angioplasty. And three of the people who received stents later required bypass surgery. None of those who had angioplasty did.
Nevertheless, Hofmann said, "Out in the community, I think you will see more widespread adoption of this technique."
But Dr. Roy Greenberg, director of endovascular research at the Cleveland Clinic, said, "I'm a little more hesitant to buy into it." One reason is the failure of stenting to stop PAD from worsening in some study participants, he said, and another is the relatively short period covered by the study.
"Will this be a prolonged benefit?" Greenberg asked. "If the benefits last six months or a year, will they last two or three years? Will there be greater problems because the stents fracture?"
Greenberg said he does use stents for some PAD patients, making the decision on a case-by-case basis.
His overall assessment of the new study: "This is one of the first pieces of evidence that show an advantage for stents in a short-term follow-up."
The case for stents in general has not yet been proven, Hofmann said. "Not all stents are created equal," he said. Subtle differences in engineering can have a major effect on the risk of stent fracture and other problems, he said.
More information
For more on peripheral arterial disease, visit the American Academy of Family Physicians.
