Carotid stenting


STENTING AND  SURGERY
COMPARED IN CREST TRIAL

Carotid stents are small metal tubes
used by doctors to open clogged
carotid arteries to reduce the risk of
strokes without the danger of cutting
open the arteries, which line the neck.
Physicians use a catheter threaded
from a patient’s groin area to reach the
clogged portion of the artery and insert
the stent.
The carotid arteries carry oxygenated
blood to the brain. These vessels face
the same threat of clogging as the
coronary arteries that supply the heart.
When the carotids become blocked or
throw off a blood clot that travels to the
brain, the result is a stroke, or brain
attack. One of the tools used in the
fight against carotid artery disease is
stenting, the insertion of a tiny tubular
wire mesh device to hold open the
artery and allow the free flow of blood
to the brain.

The largest clinical trial to date,
CREST, reported no significant
differences out to four years of follow-
up between surgery and carotid
stenting in average risk patients.
Younger patients (<70 years old) had
better outcomes with stenting than with
surgery. Patients had fewer heart
attacks with stenting, but they did have
more minor strokes. There was no
difference between surgery or stenting
for major (disabling) strokes.

Before the advent of carotid artery
stenting, a serious buildup of plaque in
these arteries was usually addressed
through a major surgical procedure
called a carotid endarterectomy.
VascularWeb describes this as "an
operation during which your vascular
surgeon removes the inner lining of
your carotid artery if it has become
thickened or damaged." This surgical
procedure is still widely used.

The placement of carotid artery stents
is a minimally invasive--though no less
serious--procedure that is generally
carried out in a hospital's
catheterization or angiography lab. A
catheter, a thin, flexible tube, is
inserted into an artery in the arm or
groin and threaded through the
circulatory system until it reaches the
carotid vessels that are blocked. The
areas of blockage are first cleared
away through the process of
angioplasty, in which a balloon-type
device at the forward tip of the
catheter is inflated to push the
deposits of plaque to the walls of the
artery. Once the blockage is removed,
a stent is inserted to keep the vessel
open in the future.
Several types of carotid stents are  
used along with a device called the
embolic protection device (EPD). The
EPD looks like an umbrella or wind
sock and contains a basket to catch
plaque particles dislodged during the
stenting procedure. Catching these
particles prevents them from traveling
in the blood to the brain and reduces
the risk of a blood clot or stroke.

Stents are made  by Abbott
Laboratories, Ev3 Inc., Boston
Scientific Corp. and Johnson &
Johnson in competition  in the carotid-
stent market.