New Heart Stent Looks Good in Study
Xience V Experimental Drug-Coated Stent May Offer Advantages Over Current Devices
March 27, 2007 (New Orleans) -- An experimental drug-coated heart stent
appears to be better at keeping blocked heart arteries open than the current
standard, a new study suggests.
In addition, the new stent, known as Xience V, appears to be at least as
good as the standard Taxus stent at reducing deaths from heart disease,
recurrent heart attacks, and the need for repeat procedures to open blocked
heart arteries, says lead researcher Gregg Stone, MD, director of
cardiovascular research at Columbia University Medical Center.
"For the patient, this means better long-term outcomes without recurrent
heart problems," Stone tells WebMD.
The study was presented at the annual meeting of the American College of
Drug-Coated Stents in Most Cases
Since they were first approved for use in the U.S. in 2003, drug-coated
stents have been the rage among cardiologists.
The stents are coated with a polymer that slowly releases a drug to keep
scar tissue from forming and reclogging heart arteries after a balloon
angioplasty procedure to open them -- a big problem with earlier, bare-metal
Research has shown that these drug-coated stents can reduce the need for
repeat procedures to clear clogged arteries and lower the risk of heart
But they’re not perfect. With drug-coated stents, reclogging is less
of a problem than with bare-metal stents, but it’s still a problem.
As a result, researchers have been looking for ways to make drug-coated
stents safer and more effective, Stone says.
Additionally, recent studies suggest drug-coated stents may carry a delayed
risk of dangerous blood clots.
The new study, designed before the blood clot risks were well known, did not
address the issue of which stent was better in that regard.
But the experimental stent has other advantages, Stone says.
Stent May Promote Faster Healing
Its very thin metal base is coated with a powerful drug called everolimus to
discourage scar tissue. Everolimus is not approved for use in the U.S.
The polymer used to deliver the drug is very thin, nonadhesive, and
nonsticky, so it may promote faster healing of the blood vessel walls.
And the metal tube itself is a highly malleable, cobalt-chromium blend. That
makes it easier for the doctor to get it exactly where he wants it, Stone
The question, he tells WebMD, was whether the polymer and stent would work
To find out, the researchers studied 1,002 people with blockages in up to
two arteries. About two-thirds got the Xience stent; the rest were implanted
with the standard Taxus stent.
After implantation, participants were treated with the drug Plavix to
prevent blood clots for at least six months.
After nine months, 8.1% of people who got the Taxus stent died, had a heart
attack, or had artery reclogging, compared with only 4.6% of those who got the