Filters Reduce Angioplasty Risks
By DANIEL Q. HANEY,
Medical Editor and special correspondent for The
Associated Press.
© The Associated Press
CHICAGO (AP) - Doctors have
found they can substantially improve the safety
of balloon angioplasty to clean out the arteries
in the neck by temporarily inserting a tiny filter
to trap stirred-up gunk before it floats to the
brain.
This approach could make angioplasty
the preferred way of treating blockages in the
carotid arteries, the main blood vessels to the
brain, researchers say.
Currently, doctors usually do this
with surgery. That operation, called carotid endarterectomy,
is now done on about 200,000 people in the United
States annually.
Doctors tested the filter on people
considered at especially high risk and found it
found it cut strokes and other serious complications
in half.
"It is a big deal. I consider
it a watershed event,'' said Dr. Donald La Van
of the University of Pennsylvania, who was not
involved in the testing.
Dr. Jay Yadav of the Cleveland Clinic
led testing of the filter approach using an experimental
device called the Angioguard, made by Johnson
&Johnson, which paid for the study. He presented
the results Tuesday at the annual scientific meeting
in Chicago of the American Heart Association.
For a generation, surgeons and heart
specialists have debated whose approach works
best: surgery or angioplasty.
For the carotid arteries, the surgical
approach - opening up the blood vessels and cutting
out the bad spots - has been the standard since
the 1950s. The goal is to restore blood flow before
clogging leads to strokes. However, the operation
itself occasionally triggers strokes by loosening
particles that get lodged in the brain.
As an alternative, heart specialists
sometimes perform angioplasty, similar to the
technique widely used to open up blocked heart
arteries. A balloon is threaded into the neck
artery and briefly inflated to squeeze open the
artery. Then a stainless steel wire coil, called
a stent, is left behind to keep the artery propped
open.
Recent studies suggest angioplasty
and endarterectomy are roughly equal in effectiveness
and complications. The new study concludes that
using the filter makes angioplasty better.
"This is the first time that
an interventional procedure has been shown superior
to surgery in cardiovascular disease. It's a turning
point,'' Yadav said.
In the procedure, doctors temporarily
insert a skinny filter that opens like an umbrella.
They do the angioplasty, insert a stent, then
collapse the filter, cover it with a tiny sheath
and drag it out of the artery. The filter catches
lumps of translucent fatty debris stirred up by
the stent.
In the study, 307 patients were
randomly assigned to get either the angioplasty
or surgery. After a month, 6 percent of those
getting the angioplasty had died or suffered a
stroke or heart attack, compared with 13 percent
of the surgery patients.
While longer follow-up is necessary,
Yadav said the first month's experience is usually
a good indicator of long-term results.
He said that 80 percent of the filters
used this way were visibly coated with particles.
Typically about half of the filter surface was
covered with material that broke loose from the
patients' arteries.
In 5 percent to 10 percent of patients,
the filter gets so clogged that blood flow to
the patients' brains slows considerably. In such
cases, Yadav said doctors quickly withdraw the
filter before brain damage occurs.
Stents are also used to hold open
arteries in the heart after angioplasty. However,
in roughly a quarter to a third of cases, those
stents quickly clog up again as tissue grows over
them.
To help solve that problem, companies
are testing stents coated with medicines that
prevent this re-growth. Last month, a Food and
Drug Administration advisory committee recommended
approving the first of these, developed by Johnson
& Johnson.
At the heart meeting on Tuesday,
Dr. Jeffrey Moses of Lenox Hill Heart and Vascular
Institute of New York presented the results of
testing on 1,101 patients. After eight months,
9 percent of the new stents had clogged up, compared
with 36 percent of the standard variety.
"We achieved an over 75 percent
reduction, which is profound and remarkable,''
Moses said.
On the Net:
Heart meeting: http://www.scientificsessions.org
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