Carotid Artery Disease
Carotid artery disease involves the two major arteries that contribute
oxygen-rich blood to the brain and head. Located on either side
of the neck, these vessels sometimes develop atherosclerosis or
plaque formation on the arterial walls. Carotid artery disease
can lead to stroke that is the third leading cause of death in
the United States.
Ischemic stroke involves the deprivation of blood and oxygen supply
to the brain. This can happen either because the plaque formation
has narrowed the artery and reduced the amount of blood flow reaching
the brain or because a clot has wedged in a narrowed carotid artery
further impairing circulatory flow. The plaque itself can also
become dislodged and travel to the brain impeding blood and oxygen
circulation.
Early diagnosis and treatment of carotid artery disease is essential
for stroke prevention. Carotid artery stenosis or narrowing of
the vessel is a major cause for the occurrence of ischemic stroke.
Prevention of carotid artery disease will significantly decrease
the incidence of stroke and its resulting disablement.
Risk Factors for Carotid Artery Disease
The risk for development of carotid artery disease increases as
we age. The incidence of its occurrence is also higher for men
than for women. Carotid artery disease risk factors are very similar
to those of coronary artery disease. In fact, those with coronary
artery disease usually demonstrate some degree of carotid artery
stenosis. Hypertension or high blood pressure, elevated cholesterol
levels, smoking, diabetes, sedentary lifestyle, and being overweight
can all contribute to the development of carotid artery disease.
Symptoms of Carotid Artery Disease
The plaque formation of carotid artery disease may develop progressively,
and the first actual symptoms of its presence can be related to
the possibility of stroke or an actual stroke event. Symptoms represent
the lack of an adequate blood supply to a specific part of the
brain. Early warning symptoms may be demonstrated as a TIA or transient
ischemic attack. This so-called “mini-stroke” is a
short-term episode of limited duration during which headache, dizziness,
lightheadedness, slurred speech, numbness, tingling, and even temporary
paralysis of a body extremity may occur. It is important to report
such an event to your physician as an emergent situation.
Other symptoms related to carotid artery stenosis are also possible
symptoms of a stroke and represent a life-threatening emergency.
They include sudden acute headache, loss of vision or blurring
of vision in one eye, paralysis of one side of the body, difficulty
swallowing, loss of speech, dizziness, lightheadedness, disorientation,
and confusion. Such symptoms require immediate medical evaluation.
Diagnosis of Carotid Artery Disease
Physical examination may indicate the possibility of carotid artery
disease. Circulatory flow through the carotid arteries can be assessed
by listening with a stethoscope for the presence of a bruit. This
is the rushing sound of the blood flowing past a blockage within
the vessel. However, significant carotid artery disease may be
present and no bruit may be detected.
Doppler imaging studies in which ultrasound waves are used to
create an image are commonly used to detect carotid artery stenosis.
Magnetic resonance angiography (MRA) utilizes strong magnetic fields
to reproduce images and may be ordered to determine the presence
of carotid artery disease. Arteriography, in which a dye is injected
via access from a major peripheral vessel, allows x-ray images
to be taken as the dye flows through the carotid artery circulation.
Treatment of Carotid Artery Disease
The goals of treatment for carotid artery disease will include
addressing the progressive nature of the disease through lifestyle
changes and medication therapy as well as the alleviation of the
stroke risk it represents through consideration of surgical options
where appropriate. As with coronary artery disease, lifestyle choice
and the management of other predisposing health conditions may
significantly decrease the occurrence and progression of carotid
artery disease.
To minimize carotid artery disease development and stroke risk,
focus on control of high blood pressure and diabetes. Minimize
the intake of fatty foods, monitor cholesterol levels, reduce salt
consumption in your diet, and limit alcohol. Do not smoke, and
pursue regular exercise as part of a healthy lifestyle. Recognize
that reducing your risk for heart disease also reduces your risk
for carotid artery disease.
Because carotid artery disease presents a risk for the occurrence
of stroke, patients may be prescribed blood-thinning medications
or anticoagulants to decrease the potential for clot formation.
Research has shown that aspirin as well as the use of blood-thinning
medications can effectively reduce the risk of stroke in the presence
of carotid artery disease. Recommendations for drug therapy are
made on an individualized basis.
Currently under investigation is the use of angioplasty and stent
placement to effectively address plaque formation within the carotid
arteries. In this technique, a balloon catheter is placed at the
site of the carotid artery blockage, and the balloon is inflated
to disrupt the plaque and reestablish adequate blood flow. A stent
is then placed at the site to prevent the reoccurrence of the blockage.
This procedure for the treatment of carotid artery disease is not
yet approved by the Food and Drug Administration.
Carotid endarterectomy is the general surgical procedure performed
to remove plaque
from the carotid artery. The surgeon will perform an open incision
in the neck area at the site of the plaque. A shunt may be used
temporarily to reestablish blood flow through the vessel. The surgeon
then removes the plaque at the site of the blockage. Not all carotid
artery blockages are candidates for the endarterectomy procedure.
The recommendation for surgery will be considered based on estimated
percentage of the blockage, the symptoms being experienced by the
patient, and the presence of other health conditions that may increase
the risk posed by the procedure itself. Following successful carotid
endarterectomy, it will remain essential to focus on the most appropriate
lifestyle choices to prevent reoccurrence and progression of carotid
artery disease.
