Stroke (Cerebrovascular Accident)
What is a stroke?
A stroke is damage to part of the brain when its blood
supply is suddenly reduced or stopped. A stroke may also be
called a cerebral vascular accident, or CVA. The part of the
brain deprived of blood dies and can no longer function.
How does it occur?
Blood is prevented from reaching brain tissue when a
blood vessel leading to the brain becomes blocked or bursts.
There are several types of strokes:
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A thrombotic stroke occurs when a blood clot
(thrombus) forms in an artery and blocks blood flow to
the brain.
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An embolic stroke occurs when a blood clot or
a piece of debris called plaque, which formed in another
vessel in the body, breaks away and flows through the
bloodstream to the brain. The clot or clump of plaque
then blocks an artery in the brain.
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A lacunar stroke is caused by a blockage in
certain small blood vessels inside the brain.
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A cerebral hemorrhage occurs when an artery
in the brain tears or bursts, causing blood to spill
out. A hemorrhage often happens without warning. It
usually occurs as a result of high blood pressure. Less
often it may result from a blood vessel defect present
since birth.
Any of the following factors can increase the risk of a
stroke:
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high blood pressure
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diabetes
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high cholesterol level
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cigarette smoking
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being overweight
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family history of stroke
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heart valve or heart muscle disease called
endocarditis
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hardening of the arteries (atherosclerosis, or fatty
cholesterol deposits on artery walls)
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heart disease (such as atrial fibrillation or
coronary artery disease)
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sleep apnea
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sickle cell anemia
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cocaine use.
Recent research has identified metabolic syndrome as
doubling the risk of stroke. It also increases the risk of
heart disease and diabetes. Metabolic syndrome, also known
as syndrome X, is defined as the presence of 3 or more of
the following 5 health conditions: obesity, low levels of
HDL cholesterol, high triglyceride levels, a blood pressure
of 130 over 85 or higher, and diabetes or prediabetes. (Prediabetes
is a fasting blood sugar between 100 and 125.) While each of
these health conditions is a risk, the combination of
disorders increases the chances of life- threatening
illness.
What are the symptoms?
The symptoms of a stroke differ, depending on the part of
the brain affected and the extent of the damage. Symptoms
following a stroke come on suddenly and may include:
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severe headache with no known cause
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weakness, numbness, or tingling in the face, arm, or
leg, especially on one side of the body
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trouble walking, dizziness, loss of balance, or
coordination
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inability to speak or difficulty speaking or
understanding
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trouble seeing with one or both eyes, or double
vision
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confusion or personality changes
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difficulty with muscle movements, such as
swallowing, moving arms and legs
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loss of bowel and bladder control
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loss of consciousness.
Warnings known as transient ischemic attacks (TIAs) may
happen before the actual stroke. TIAs occur when the blood
supply to the brain is reduced for a short time without
causing permanent damage. A TIA is sometimes referred to as
a ministroke because it causes the same symptoms as a stroke
but the symptoms go away within minutes to a few hours.
Call 911 if you see or have any of these symptoms.
Treatment can be more effective if given quickly. Every
minute counts.
How is it diagnosed?
If symptoms of a stroke occur, someone should call an
ambulance or take you to an emergency room right away.
Your health care provider will know from your symptoms
and physical exam whether you are having a stroke.
The following tests may be done:
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lab tests of your blood
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electrocardiogram (ECG) to see how well your heart is
working
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x-ray of your chest
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brain scans (CT or MRI) to try to identify a stroke and
determine whether it is from a clot or from bleeding into
the brain from a leaking artery (hemorrhage).
How is it treated?
It is important to get to the hospital as soon as
possible if you suspect a stroke. Many large hospitals are
now treating strokes caused by blood clots with
clot-dissolving medicines. These medicines can cause the
symptoms to stop very quickly. They can prevent long-term
disability or death. This treatment works only if the
medicines are given within the first 3 to 6 hours after the
stroke began.
All strokes require careful observation, especially in
the first 24 hours. In addition to bed rest, you will
probably need an IV and oxygen. Underlying medical problems
that may have caused the stroke, such as high blood pressure
or heart rhythm problems, will be treated.
Depending on the severity of your symptoms and how soon
you are alert and able to start exercises, in the bed or out
of the bed, you will begin your rehabilitation (rehab)
program. Most stroke rehab programs last several weeks to
several months after you leave the hospital. The program
consists of physical therapy, occupational therapy and, if
needed, speech therapy.
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Physical therapy helps you regain muscle strength
and teaches you ways to move safely with weak or
paralyzed muscles.
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Occupational therapy helps you relearn ways of
eating, dressing, and grooming.
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Speech therapy may help you if you have problems
with swallowing, speaking or understanding words.
How long will the effects last?
Recovery depends on the extent of the brain injury. Some
improvement may occur rapidly within the first few days and
weeks after the stroke. Other improvement may occur more
gradually. Rehabilitation may include physical therapy to
strengthen muscles, occupational therapy to teach such
things as dressing and eating, and speech therapy, if
needed. If recovery does not begin within 1 to 2 weeks of
the stroke, some muscle movement and speech may not return.
However, some people continue to regain speech and muscle
strength up to 1 year after a stroke. By the end of the
rehab program, your health care provider can tell you more
accurately what further recovery you can expect.
How can I take care of myself?
Discuss with your health care provider the cause of your
stroke, and follow his or her advice on how to avoid another
one. Your provider may advise diet changes, regular
exercise, and programs for stress management.
How can I prevent a stroke from occurring?
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If you have high blood pressure, it is essential
that you control it with medicine.
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If you have diabetes, monitor and control your blood
sugar.
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If you have an irregular or fast heart rate, you may
need to take medicine such as warfarin, aspirin, or
clopidogrel. Talk with your health care provider about
this.
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If you smoke, quit.
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Keep your diet low in fat to decrease the risk of
developing fatty deposits in your blood vessels.
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Exercise every day according to your health care
provider's recommendations.
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Keep a healthy weight.
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