An aneurysm is a swelling in part of an
artery caused by damage to, or weakness
of, a blood vessel wall. The widening may
be small, spherical and berry-size, which
normally occur near blood vessel branches,
or larger and balloon-like (saccular aneurysm).
Large aneurysms may also extend along arteries
(fusiform aneurysm). Aneurysms may occur
anywhere in the body, but there are two
places which are most common: on the largest
artery in the body, the aorta, and on the
small circle of arteries underneath the
base of the brain called the Circle of Willis.
An aneurysm can also
occur on the heart wall after a section
has been weakened by local loss of blood
supply from a heart attack (myocardial infarction).
Aneurysms may affect
people of any age and both sexes, although
they are more common in men, people with
high blood pressure and those over 65. Aortic
aneurysms tend to run in families. All aneurysms
can be life-threatening especially if they
burst.
Causes
The cause of most
aneurysms is unknown although aneurysms
of larger arteries, such as the aorta, are
thought to be largely due to build-up of
fat in artery walls (atherosclerosis). Brain-artery
aneurysms are due in most cases to a weakness
in the artery wall that has been present
from birth.An aneurysm can also be caused
by an injury to an artery that does not
rupture the wall but weakens it, so that
blood pressure gradually balloons out the
vessel. Another much less common cause of
aortic aneurysm is the genetic disease Marfan’s
syndrome
Treatment
All kinds of aneurysm,
once diagnosed, can be treated. Surgical
treatment is highly skilled and is always
given in hospital. With small berry aneurysms
the usual treatment is to clip them or to
cause the blood in them to clot. Sometimes
the aneurysm is packed with a piece of muscle,
gauze or plastic that will encourage clotting
and the formation of strong fibrous tissue.
It may be necessary to tie off a larger
artery leading to the artery with the aneurysm.
The affected person is nursed under strict
bed rest in a darkened room. Measures are
taken to avoid any strain or exertion, and
drugs are given to keep the blood pressure
reasonably low, to control any tendency
to seizures and to relieve the headache.
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Aneurysm
