March 13, 2006
Drug-coated stents work where older stents failed
CHICAGO (Reuters) - Heart patients whose coronary arteries
reclogged after treatment with a bare-metal stent can be
treated by simply inserting a newer, drug-eluting stent inside
the old stent, new data suggests.
Two clinical studies indicate that inserting a stent
covered with the drug paclitaxel or sirolimus inside the old
clogged stent reduces the risk of the vessel re-narrowing when
compared with in-vessel radiation treatment.
A re-narrowing of the vessel, known as in-stent restenosis,
is a common problem with bare-metal stents and is often treated
with radiation. The introduction of drug-eluting stents in the
United States three years ago reduced that risk significantly.
The studies -- one sponsored by stent maker Boston
Scientific Corp. and the other sponsored by rival Johnson &
Johnson -- were presented at the American College of Cardiology
meeting in Atlanta on Sunday and published by the Journal of
the American Medical Association.
A JAMA editorial noted that about 1 million bare-metal
coronary stents were implanted in the United States in 2003, a
time when the use of bare-metal stents peaked.
"This means at least 100,000 in-stent restenosis lesions
occurred, making this an important clinical problem," the
editorial said, adding that the benefits of radiation therapy
have been mitigated by safety concerns.
The Boston Scientific-sponsored study of 396 patients
showed that patients who received the paclitaxel-covered stent,
called Taxus, had a 53 percent lower rate of restenosis
compared with radiation treatment after 9 months.
The J&J-sponsored study of 384 patients showed that 12.4
percent of those who received the sirolimus-eluting stent,
called Cypher, experienced cardiac death, heart attack or
required the artery to be reopened after 9 months, compared
with 21.8 percent who received radiation.