CHAPTER 18
STROKE
LAWRENCE M. BRASS, M.D.
INTRODUCTION
Stroke is a form of cardiovascular disease affecting
the blood supply to the brain. Also referred to as
cerebrovascular disease or apoplexy, strokes actually
represent a group of diseases that affect about one
out of five people in the United States. When physicians
speak of stroke, they generally mean there has
been a disturbance in brain function, often permanent,
caused by either a blockage or a rupture in a
vessel supplying blood to the brain.
In order to function properly, nerve cells within
the brain must have a continuous supply of blood,
oxygen, and glucose (blood sugar). If this supply is
impaired, parts of the brain may stop functioning
temporarily. If the impairment is severe, or lasts long
enough, brain cells die and permanent damage follows.
Because the movement and functioning of various
parts of the body are controlled by these cells,
they are affected also. The symptoms experienced by
the patient will depend on which part of the brain is
affected.
Stroke is a major health problem in this country.
Nearly 500,000 people in the United States have a
stroke each year, and nearly a third of these people
die during the first few months after their stroke, Of
those who survive, about 10 percent are able to return
to their previous level of activity, about 50 percent
regain enough function to return home and carry on
with only limited assistance, and about 40 percent
remain institutionalized or require significant assistance
in caring for themselves.
While the incidence of stroke has decreased a
great deal over the past few decades, there is evidence
that this trend may be leveling off.
Stroke is costly. The cost in human terms, to patients
and their families, is impossible to estimate. The
cost to the U.S. economy—in terms of medical care
and lost income—amounts to over $25 billion each
year.
Although stroke is often viewed as a disease of the
elderly, it sometimes affects younger individuals. The
incidence of stroke does increase with age, but nearly
a quarter of all strokes occur in people under the age
of 60.
Stroke patients are often cared for by neurologists,
because of the complex nature of the symptoms
caused by damage to the brain. However, strokes are
very closely related to heart disease. Heart attacks
(myocardial infarctions) and stroke are both caused
by diseases of the blood vessels. They share many of
the same risk factors, and modifying these risk factors
may reduce the possibility of stroke. Many of the therapies
used for cardiac disease show promise for some
types of stroke. Finally, people who already have coronary
disease may be at greater risk for stroke, and
vice versa.
HOW THE BRAIN FUNCTIONS
To understand the signs and symptoms of stroke and
why they can differ from patient to patient, it is necessary
to understand a little about the brain and how
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MAJOR CARDIOVASCULAR DISORDERS
it functions. There are literally thousands of possible
symptoms that can result from a stroke, depending
on which blood vessels and parts of the brain are
involved. It is also important to realize that except for
a brief period after birth, brain cells are unable to
divide and form new cells. When brain cells die, they
are not replaced. This is part of the reason for the
limited ability of the brain to repair itself after injury,
and why recovery from stroke is only partial in many
cases. While someone who suffers a heart attack, for
example, can lose 10 percent of heart tissue and still
run a marathon, losing 10 percent of the tissue in
certain parts of the brain can result in a devastating
disability.
The human brain is the most complex structure
known. It is composed of 100 billion nerve cells, called
neurons; each neuron may connect to thousands of
other brain cells. The trillions of connections are necessary
for the integrative power of the brain. They
also control body movements, interpret all sensations
(hearing, vision, touch, balance, pain, taste, and
smell), and mediate thought and language. Different
areas of the brain control different functions. (See
Figure 18.1.)
Although the brain represents only 2 percent of
the body's weight, it uses about 25 percent of the
body's oxygen supply and 70 percent of the glucose
(sugar). Unlike muscles, the brain cannot store nutrients,
and thus it requires a constant supply of glucose
and oxygen. If the blood supply is interrupted
for as little as 30 seconds, unconsciousness results;
permanent brain damage may follow in as little as
four minutes. The brain’s high metabolic rate, sensitivity
to changes in blood flow, and dependence on
continuous blood flow are what can make strokes so
dangerous. Figure 18.2 shows the major arteries supplying
the brain.
The brain can be divided into three areas: brain
stem, cerebellum, and cerebrum. The brain stem controls
many of the body’s basic functions, including
breathing, chewing, swallowing, and eye movements.
The major pathways from the cerebrum—the
thinking part of the brain—also pass through the
brain stem to the body. The cerebellum, attached to
the back of the brain stem, coordinates movements
and balance.
The cerebrum is divided into two hemispheres, left
and right. In general, the left brain receives input
(sensations) from the right side of the body and controls
movement on the right side, so that a stroke in
the right side of the brain will cause left-sided weakness.
Conversely, the right brain controls the left side
of the body.
Each side of the cerebrum is further divided into
four lobes. The frontal lobes control motor function,
planning, and expression of language. The temporal
Figure 18.2
Shown are the major arteries feeding the brain. The carotid and its
branches (anterior cerebral artery and middle cerebral artery) feed
the front part of the brain and most of the cerebral hemispheres (top
of the brain). The vertebral arteries join in the back of the head to
form the basilar artery. These arteries and their branches supply the
brain stem, cerebellum, and back parts of the brain.
lobes are involved with hearing, memory, and behavior.
The parietal lobes interpret sensation and
control understanding of language. The occipital
lobes perceive and interpret vision. The right and the
left sides of the cerebrum are not identical, but rather
have specialized functions. In almost all right-handed
people and most left-banders, the left brain is “dominant”
and performs most language functions. The
right side of the brain controls the abilities to understand
spatial relations and recognize faces, as well as
musical ability. It also helps focus attention.
RISK FACTORS AND STROKE
PREVENTION
Given the devastating deficits often associated with
a stroke, the need for prevention is obvious. Many of
the risk factors for stroke (see box, “Stroke Risk Factors”)
can be treated or modified. Doing so may prevent
an initial stroke or recurrent strokes, as well as
decrease the risk of premature death, which is most
often the result of coronary disease.
A number of stroke risk factors are the same as
those for heart disease, although their relative importance
varies. For example, a high blood cholesterol
level is a much more significant risk for heart
disease. This distinction is of little practical importance,
because both coronary and stroke risk factors
should be addressed in patients who are at risk for,
or who have suffered, a stroke or a transient ischemic
attack. (The latter, also called a TIA or a ministroke,
is discussed later in this chapter.)
Three of the greatest risk factors for stroke—high
blood pressure (hypertension), heart disease, and
diabetes—often do not cause symptoms in their earliest
stages. For this reason, it is important that all
adults, but especially those with a family history of
heart disease or stroke, have regular screening for
Stroke Risk Factors
Characteristics and life-style
Definite
Cigarette smoking
Excessive alcohol consumption
Drug use (cocaine, amphetamines)
Age
Sex
Race
Familial and genetic factors
Possible
Oral contraceptive use
Diet
Personality type
Geographic location
Season
Climate
Socioeconomic factors
Physical inactivity
Obesity
Abnormal blood lipids
Disease or disease markers
Hypertension
Cardiac disease
TIA
Elevated hematocrit
Diabetes mellitus
Sickle cell disease
Elevated fibrinogen concentration
Migraine headaches and migraine equivalents
Carotid bruit
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MAJOR CARDIOVASCULAR DISORDERS
these and other vascular risk factors. Routine checkups
should begin at age 20 and be repeated at least
every five years, more frequently in later years or if
warranted by the results of the initial screening.
Blood pressure should be checked more frequently.
HIGH BLOOD PRESSURE
A major risk factor common to both coronary heart
disease and stroke, high blood pressure is present in
50 to 70 percent of stroke cases, depending primarily
on the type of stroke. The long-term effects of the
increased pressure damage the walls of the arteries,
making them more vulnerable to thickening or narrowing
(atherosclerosis) or rupture.
There is no specific blood pressure reading that is
considered normal, but rather a range. Most experts
agree, however, that a reading greater than 140/90
mm Hg is abnormal, and anyone with such a reading
should see a physician. But even mild elevations in
blood pressure are associated with an increased risk
for stroke. Sometimes mildly elevated blood pressure
can be controlled by life-style modification, but medication
is often needed. Although the patient may feel
no different, control of blood pressure is associated
with a marked decrease in the occurrence of stroke.
(See Chapter 12.)
HEART DISEASE
Just as strokes area strong risk factor for heart disease,
heart disease is a strong risk factor for stroke,
although only for one type of stroke, ischemic strokes.
Heart disease is associated with stroke in two ways.
First, damage to the heart (as, for example, from a
heart attack) may make it more likely that clots will
form within the heart. These clots can break loose
and travel to the brain, causing a cardioembolic
stroke. Heart disease and stroke are also associated
because they are both manifestations of atherosclerotic
disease in the blood vessels. If the blood vessels
feeding the heart (the coronary arteries) are diseased,
it is likely that arteries to the brain are also affected.
Patients with evidence of coronary artery disease,
congestive heart failure, left ventricular hypertrophy
(enlargement of the left side of the heart), disease of
the heart valves, or arrhythmias (irregular heart
rhythms) have a several-fold increase in the risk of
stroke.
Several recent studies suggest that people with
atrial fibrillation who take daily doses of either aspirin
or warfarin (Coumadin) have a reduction of up to 80
percent in their risk of stroke. These findings suggest
that an estimated 20,000 to 50,000 strokes might be
prevented each year if all people with this condition
had prophylactic drug treatment.
SMOKING
Smoking facilitates atherosclerosis and appears to be
an independent risk factor for strokes that result from
a clot. It also seems to be a risk for strokes that result
from cerebral hemorrhage.
Men in Framingham, Massachusetts-a community
studied extensively for cardiovascular disease—
who smoked more than 40 cigarettes a day had twice
the stroke risk of men who smoked fewer than 10. In
a large Harvard Medical School study of women, the
number of cigarettes smoked was found to be directly
related to stroke risk. Women smoking more than 25
cigarettes a day had a 2.7 times greater risk of stroke
from a clot or embolus and a 9.8 times greater risk
of a hemorrhagic stroke. Data from both the Framingham
Heart Study and the Honolulu Heart Study
indicate that one can significantly reduce stroke risk
by stopping smoking. Five years after they stop, exsmokers
have a stroke risk equal to that of nonsmokers.
DIABETES
People with diabetes are at greater risk for stroke,
just as they are for heart disease. Women with diabetes
are at an even greater risk than men. High blood
pressure compounds the risk. Although treatment of
diabetes has not been conclusively shown to reduce
risk, it is known that control of high blood sugar (hyperglycemia)
can reduce the severity of cerebral damage
during a stroke. For this and other reasons,
diabetics should keep their blood glucose levels under
strict control.
CHOLESTEROL
Studies have found a link between high blood lipid
levels and atherosclerosis in cerebral arteries, but it
is still unclear whether high cholesterol levels significantly
increase stroke risk. They do, however, increase
heart disease risk, so efforts should be made
to reduce them.
OBESI’IY AND INACTIVITY
Obesity and a sedentary life-style are risk factors for
stroke primarily because they increase the risk of
STROKE
high blood pressure, heart disease, and diabetes.
They may also be independent stroke risk factors.
Losing weight and following a moderate exercise
regimen can help reverse these risks.
ORAL CONTRACEPTIVES AND ESTROGEN
REPLACEMENT THERAPY
The role of oral contraceptives in stroke risk is still
inconclusive, primarily because most research has
looked at the effects of high-dose estrogen pills, and
most women now use lower-dose preparations. Estrogen
is believed to promote blood clotting; lowerdose
estrogen preparations are thought to minimize
this effect. Because studies have found no increase in
current risk of stroke or heart attack in women who
previously used oral contraceptives, it is believed that
the pill does not promote atherosclerosis.
Several retrospective studies have suggested that
oral contraceptive use is associated with an increase
in stroke risk, while other studies have only found a
significant risk of brain hemorrhage in women over
age 35 who take the pill and smoke. Smokers who
have migraine headaches and take oral contraceptives
may be at a particularly high risk of stroke. Experts
usually advise women who smoke not to use
oral contraceptives—or better, to quit smoking.
In contrast, there is evidence to suggest that estrogen
replacement therapy for postmenopausal
women may slow the atherosclerotic process. In this
group the use of estrogens may actually lower the
risk of stroke (and heart disease).
HISTORY OF TRANSIENT ISCHEMIC
ATTACKS (TIAs)
Researchers are learning that these “ministrokes”
may be the most reliable warning of an imminent
“full” stroke. Between 10 and 50 percent of strokes,
depending on the type, are preceded by TIAs; if not
treated, about one-third of all people who have a TIA
goon to have a stroke within five years, TIAs are also
indicators of potential coronary heart disease: Each
year, 5 percent of those who have had at least one
TIA have a heart attack. Anyone who has had a TIA
should do whatever possible to reduce other risk factors.
Drug therapy or surgery may be warranted to
reduce the risk of subsequent TIAs, . stroke, or heart
attack.
HEREDITY AND FAMILY HISTORY
The chance of having a stroke is higher for people
who have a family history of this disease. Part of the
risk is due to inherited risk factors and part to family
life-styles (eating and exercise habits, for example).
The presence of inherited risk factors does not
mean that risk cannot be lowered. In one study, for
instance, the hereditable risk for vascular disease was
mostly due to a susceptibility to the effects of cigarette
smoking. When cigarette smoking was eliminated,
the hereditable effect was significantly lowered.
The risk of stroke rises significantly with age. After
55, it more than doubles with each passing decade.
Each year, about 1 percent of people between ages
65 and 74 have a stroke—and 5 to 8 percent of people
in that age group who have had a TIA go on to stroke.
Although risk associated with advancing age cannot
be changed, it is an important factor in assessing
stroke risk and planning preventive therapies.
AN EARLIER STROKE
Because the same factors that caused a first stroke
are likely to cause a subsequent one, the risk of stroke
for someone who has already had one is increased.
CAROTID BRUIT
A bruit is a noise made by turbulent flow in a blood
vessel that usually can be heard only with a stethoscope.
The most common cause is a narrowing of an
artery because of atherosclerosis. Bruits tend to occur
in the large arteries of the body, including the
carotid artery in the neck. Even in patients without
other symptoms, carotid stenosis (narrowing) and carotid
bruits are associated with an increased stroke
rate of 5 percent each year. Over the course of a
lifetime, the cumulative stroke risk may be quite high.
The increased risk associated with the presence of
a carotid bruit has prompted some physicians to recommend
a surgical procedure called carotid endarterectomy
to open the narrowing. Initial results of
this procedure have proved disappointing in terms
of preventing strokes. Patients with asymptomatic
bruit should, if possible, be considered for referral to
a medical center that has special expertise in cerebrovascular
disease and is participating in a welldesigned
clinical trial.
OTHER RISK FACTORS
Other factors influence stroke risk, although to a
lesser extent. These include an elevated hematocrit
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MAJOR CARDIOVASCULAR DISORDERS
(number of red cells in the blood), geographic location
(especially the southeastern United States, which
is sometimes called the “stroke belt"), lower socioeconomic
status, Type A personality (see Chapter 8),
use of cocaine and amphetamines, and high alcohol
consumption. Stroke deaths seem to occur more
often during periods of extreme heat or cold.
TRANSIENT ISCHEMIC ATTACKS
(TIAs)
A transient ischemic attack is a localized neurological
problem caused by ischemia (decreased blood flow)
that completely resolves within 24 hours. Most last
only a few minutes. People who suffer a TIA often
pass it off as nothing, especially when it goes away
almost as quickly as it came. The more neurologists
learn about the cause of TIAs, the more clear it becomes
that a TIA presents a unique opportunity to
prevent a stroke.
The importance of a TIA is not in its neurological
symptoms-by definition, they disappear. Rather it
is that a third of all patients will go on to have a stroke.
TIAs represent about 10 percent of all cerebrovascular
disease. Up to half of patients who suffer an
ischemic stroke will report having had a TIA, and may
never have sought treatment. TIAs also identify a
group of people at high risk for heart attack. It is
imperative that anyone who experiences a TIA consult
a doctor for both neurological and cardiovascular
evaluation. The key is to make the diagnosis and work
to lower the risk.
The symptoms of a TIA are similar to those of a
stroke-weakness or numbness on one side of the body,
inability to speak or understand language, or lack of
coordination-except they don’t last as long. Any
combination of the symptoms described for stroke,
lasting more than a few seconds, should be considered
as a possible TIA. (See box, “Common Warning
Signs of Stroke and Transient Ischemic Attack.”)
One additional common symptom of a TIA is transient
monocular blindness, also called amaurosis fugax
(flight of darkness). This is a brief change or
distortion of vision in one eye that is often described
as a misting, clouding, blurring, spottiness, or the
sensation that a blind is being drawn down over
the eye.
The evaluation of a patient for a TIA is similar to
that for a stroke. Most patients will be hospitalized
Common Warning Signs of
Stroke and Transient Ischemic
Attack (TIA)
Because brain cells can die very quickly after a
stroke, it is crucial to recognize warning signs of
an impending stroke and get to a hospital
quickly. Since the brain controls hundreds of
activities, the range of stroke symptoms is
broad. In spite of this, there are several
common warning signs of stroke or TIA:
l Sudden weakness or numbness of the face,
arm, and leg on one side of the body
l Loss of speech, or trouble speaking or
understanding speech
l Dimness or loss of vision, particularly in only
one eye or half of both eyes
l Sudden onset of blurred or double vision
l Unexplained dizziness
l Sudden onset of unsteadiness, lack of
coordination, difficulty walking, or falling
l Sudden excruciating headache
l Recent change in personality or mental
abilities, including memory loss
Although many of these symptoms can be caused
by other diseases, the sudden onset of new
neurological symptoms should prompt a person
to seek immediate medical attention.
because of the concern of a subsequent stroke and
the need for immediate treatment should one occur.
Patients at low risk of stroke and those whose general
medical condition precludes aggressive treatment
may be followed on an outpatient basis.
The first step is to consider, and exclude, other
disease that can mimic a TIA. (See box, “Conditions
That Can Mimic a TIA.”) Many of these diseases are
serious neurological problems that also may require
urgent treatment. After other diseases have been excluded,
the physician will try to determine the mechanism
of the TIA in order to help guide decisions
about treatment. Most TIAs are due to either an embolus
(blood clot) or restricted blood flow-often
caused by a narrowing in the carotid artery. Brief
TIAs (lasting less than 10 minutes) are commonly associated
with carotid stenosis (artery narrowing),
while longer-duration TIAs (lasting more than one
hour) are more often caused by embolism.
If a TIA is due to restricted blood flow because of
a carotid artery stenosis, surgery may be indicated.
Hypoglycemia (low blood sugar)
Other’ forms of stroke
Brain tumor
Arteriovenous malformation
Multiple sclerosis
Incipient syncope (fainting)
Orthostatic hypotension (low blood pressure)
Cardiac arrhythmia (irregular heartbeat)
Amnesia
Narcolepsy/cataplexy (disorders of excessive
sleepiness)
Intracranial inflammation (e.g., brain infection)
Periodic paralysis
Pressure neuropathy (nerve compression)
Dizziness of uncertain cause
Anxiety
Hyperventilation
Labyrinthine (inner-ear) disease
If it is due to an embolus from the heart (as may occur
with various abnormal heart rhythms), even if there
is a carotid stenosis, surgery may not be appropriate.
(For treatment options, see the discussion of longterm
treatment of TIA and stroke elsewhere in this
chapter.)
ISCHEMIC STROKE
There are two broad categories of stroke: ischemic
and hemorrhage. Ischemic strokes are caused by a
Figure 18.3
STROKE
lack of blood flow to the brain and account for about
70 percent of all strokes. (See Figure 18.3.) Hemorrhagic
strokes, discussed later in this chapter, are
caused by bleeding into the brain or adjacent tissues.
Within the category of ischemia, there are several
subcategories of stroke. One common type, called cerebral
atherothrombosis (also referred to as large artery
disease), is caused by a clot (thrombus) that
blocks blood flow in an artery. The narrowing leads
to a low flow state referred to as watershed (or distal
field) ischemia. (See Figure 18.4.) If the resulting lack
of oxygen results in death of brain tissue and permanent
damage, the term cerebral infarction is used.
Clots usually do not occur in healthy arteries, but
tend to form at or adjacent to an area of a vessel
damaged by atherosclerosis. In the atherosclerotic
process, plaque—an amalgam of fatty substances,
cholesterol, waste products of cells, calcium, and a
blood-clotting material called fibrin-builds up as
thick, irregular deposits on the inner lining of an artery.
The irregular surfaces that plaque deposits create
provide ideal places for clots to form and grow.
In some cases, plaque deposits themselves can grow
so large that they obstruct the opening (lumen) of the
blood vessel and block the flow of blood. Surgery is
often indicated to open these arteries.
Atherothrombic strokes are often preceded by
TIAs, and they tend to occur at times when blood
pressure is low—at night during sleep, or early in the
morning before major activities start.
Another kind of ischemic stroke involving a clot is
called a cerebral embolism or embolic stroke. This
type is caused by a wandering clot (embolus) that
forms in one part of the body, breaks loose (in whole
or part), and travels in the bloodstream until it lodges
in an artery in the brain or in a vessel leading to the
brain. (See Figure 18.5.) Emboli can be formed from
MAJOR CARDIOVASCULAR DISORDERS
Branches of anterior cerebral arteries
Figure 18.4
A watershed (or distal field) stroke is the result of narrowing
of the large arteries feeding the brain.
Figure 18.5
An embolic stroke is the result of a blood clot that forms in another
part of the body and travels in the bloodstream until it lodges in an
artery in the brain.
Branches of anterior cerebral arteries
Branches of anterior cerebral arteries
Figure 18.6
A lacunar stroke is the result of the complete blockage of an
arteriole, the very small end of an artery that penetrates deep into
the brain.
calcium, cholesterol, air, blood proteins, platelets, or
by-products of an infection of the heart’s inner lining
(endocarditis). (See Chapter 15.) It is believed that
most ernbolic strokes involve clots from the heart or
the carotid arteries.
The most common cardiac conditions associated
with emboli are atrial fibrillation, valvular disease, the
presence of a prosthetic heart valve, endocarditis,
congestive heart failure, and myocardial infarction.
In atrial fibrillation, the two upper chambers of the
heart (atria) quiver rather than beat effectively. Because
blood is not pumped out of the atria (upper
part of the heart) completely it tends to pool and form
clots. One-third of all people with atrial fibrillation
will have a stroke at some time, and the majority of
these strokes will be embolic. Embolic strokes are
probably the most common of ischemic strokes.
(Many that have no proven cause are thought to be
caused by embolism.) The use of anticoagulant drugs
may help reduce the risk of clot formation-before
or after such a stroke. (In fact, almost all people with
atrial fibrillation should be on some form of longterm
aspirin or anticoagulant drug therapy. See
Chapter 23.)
The third form of stroke caused by blood clotting
is called a lacunar infarction or lacunar stroke. These
strokes are the result of occlusion (complete blockage)
of arterioles, the very small ends of the arteries
that penetrate deep into the brain, (See Figure 18.6.)
The small size of the vessels sometimes makes lacunar
strokes difficult to diagnose; in addition, some have
no noticeable symptoms. There are, however, several
classic syndromes that suggest the possibility of a
lacunar infarction. The most common is a pure motor
stroke, in which damage is confined to the main cabling
system for motor signals from the brain to the
spinal cord (internal capsule). As a result, the patient
develops one-sided weakness without other symptoms.
Similarly, a lacunar stroke in the thalamus (the
main sensory relay center to the brain) can cause a
pure sensory stroke. Surgery and the use of anticoagulant
drugs do not appear to help a great deal
in the short-term management of people with lacunar
disease. Treatment concentrates on modification of
long-term risk.
In spite of the most aggressive workup available
in the 1990s, the mechanism of ischemic stroke remains
unknown in over a third of all cases. Many of
these cases of infarction of unknown cause appear to
be due to embolism. Refinements in imaging technology
and earlier evaluation of patients may help
categorize these strokes better in the future.
At present, however, much can be determined by
the specific symptoms and signs that a patient manifests.
Defining the mechanism of a stroke can help
determine prognosis, suggest appropriate therapy,
and help the physician prepare the family for what
to expect. For example, patients with lacunar stroke
often recover their strength better than those who
suffer other types; thrombotic strokes tend to worsen
during the acute period before recovery begins; and
embolic strokes are associated with a high rate of
recurrence within the first few weeks. “
STROKE
the walls of these small arteries, and eventually they
burst. The term “cerebral” (meaning related to the
part of the brain called the cerebrum) is also used.
About two-thirds of patients with an intracerebral
hemorrhage have a history of hypertension; diabetes
and atherosclerosis accelerate the damage. Other
causes of bleeding into the brain include brain tumor,
trauma, arteriovenous malformation (AVM), and
stimulant drugs such as amphetamines and cocaine.
Intracerebral hemorrhage accounts for about 10
to 15 percent of all strokes. The onset of symptoms
is usually acute, with severe headaches and decreased
consciousness. Other symptoms depend on the size
and location of the hemorrhage. One type of brain
hemorrhage, cerebellar hemorrhage, is especially important
to recognize because prompt evaluation,
often followed by surgery, can be lifesaving. Cerebella
hemorrhage means bleeding into the cerebellum
(rather than the cerebrum)—the part of the brain
that coordinates movement and balance. Its symptoms
usually include disequilibrium or dizziness,
incoordination (especially trouble in walking), headache,
nausea, and vomiting.
Treatment and prognosis of intracerebral hemorrhage
varies with the size and location of the hemorrhage
within the brain and the condition of the
patient. A hematoma (blood that has clotted) near the
surface may be easily evacuated (removed surgically),
but deep bleeding may damage critical structures
within the brain and pose a higher surgical risk.
Whether surgery is performed or not, medical management
centers on respiratory care, blood pressure
management, and minimizing pressure within the
skull. Seizures sometimes follow the hemorrhage, so
anticonvulsant medications are often added to the
regimen.
HEMORRHAGIC STROKES
Hemorrhage accounts for about 20 to 25 percent of
all strokes. In these strokes, blood seeps from a hole
in a blood vessel wall into either the brain itself (intracerebral
hemorrhage) or the space around the
brain (subarachnoid hemorrhage).
BRAIN OR INTRACEREBRAL HEMORRHAGE
In this type of hemorrhagic stroke, blood leaks from
small vessels at the base of the brain. Long-term exposure
to high blood pressure is thought to weaken
SUBARACHNOID HEMORRHAGE
Subarachnoid hemorrhage is usually caused by an
aneurysm or a vascular malformation (described below).
In addition to the damage caused by the blood
shooting out of the artery, damage can be further
worsened by the mass of blood pushing up against
adjacent areas of the brain and blood vessels, or
through secondary effects of the extruded blood on
the brain’s blood vessels (vasospasm).
The classic clinical feature of a subarachnoid hemorrhage
is the sudden onset of an excruciating headache.
It is often associated with a stiff neck, change
in consciousness, nausea and vomiting, diffuse intellectual
impairment, and seizures. Other symptoms
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MAJOR CARDIOVASCULAR DISORDERS
may occur, depending on the location and size of the
hemorrhage.
Patients with symptoms suggestive of a subarachnoid
hemorrhage should have a CT scan, which will
indicate the presence of blood in about 80 percent of
cases. If the CT scan is negative or equivocal, a spinal
tap (lumbar puncture) should be performed to look
for evidence of bleeding.
ANEURYSM
An aneurysm is an outpouching in the wall of a blood
vessel that forms at a point where the wall is weak.
Although the weakness may be present at birth, the
aneurysm usually forms and grows later in life. The
outpouching may go unnoticed for years, or may suddenly
rupture, in which case it can sometimes be fatal.
The peak age range for an aneurysm rupture is between
40 and 60 years old. Aneurysms sometimes run
in families; some are associated with other diseases.
About a quarter of patients with one aneurysm will
have additional ones.
The major impact of an aneurysm is the result of
the rupture and bleeding, but the event may be followed
in a few days by a secondary constriction of
blood vessels, known as vasospasm. The vasospasm
may be so severe that it impairs blood flow to the
brain and causes a secondary ischemic stroke. Some
advances have been made recently in treating vasospasm
by using medications such as nimodipine (Nimotop),
increasing the blood volume (usually done
with intravenous fluids), or using medications to increase
blood pressure.
An aneurysm can be treated surgically by placing a
clamp at the base. The timing and type of surgery varies
with the size and location of the aneurysm, the extent
of the bleeding, and the neurological status of the patient.
Under ideal circumstances, the surgery should be
performed within 48 hours after the hemorrhage. This
eliminates the risk of rebleeding. Surgery attempted
five to ten days after a subarachnoid hemorrhage may
cause, or worsen, vasospasm.
Occasionally an aneurysm will be found before it
ruptures. It may be found because it is has pushed
against important nerves or areas of the brain, causing
pain or other symptoms, or because clots formed
in the pouch of the aneurysm have traveled downstream
and occluded a blood vessel, causing a TIA
or stroke. Surgical clipping is usually recommended
for unruptured aneurysms more than 10 mm (twofifths
of an inch) in diameter.
ARTERIOVENOUS MALFORMATION
An arteriovenous malformation (AVM) is a tangle of
arteries and veins without the small vessels (capillaries)
that normally connect the two. The walls of the
vessels are often thin and have high rates of blood
flow, conditions that predispose to bleeding. AVMs
may produce symptoms by bleeding, putting pressure
on structures within the brain, or shunting blood
away from normal areas of the brain.
Small AVMs may not need to be treated, but when
they are large or they cause significant symptoms,
attempts should be made to obliterate them. This can
be done surgically, by using radiation, or with a relatively
new radiologic technique that delivers small
pellets of glue that occlude the vessels leading to, and
within, the AVM. Unfortunately many AVMs tend to
recur.
Despite dramatic advances in our ability to diagnose
the causes of intracerebral hemorrhages, the
results of treatment remain disappointing. Mortality
remains high, and problems in those surviving are
often severe.
OTHER FORMS OF STROKE
In addition to the major causes of stroke described
above, there are a number of other causes, including
the two most common ones: cardiac arrest and hematomas
adjacent to the brain. In cardiac arrest, the
heart stops pumping blood or does not pump effectively,
and the brain is deprived of both oxygen and
glucose. Although the entire brain is affected, certain
areas are more vulnerable. Memory and coordination
are among the most frequent deficits after this type
of stroke.
Hematomas—accumulations of blood that are the
result of hemorrhage—sometimes occur in the outermost
covering of the brain, the subdural or epidural
layers. These are usually caused by injury, but may
occur spontaneously, especially in the elderly. In this
type of stroke, surgery can usually correct the problem
by removing the clot, and maybe lifesaving.
DIAGNOSING AND ASSESSING
STROKE
Anyone experiencing symptoms of a stroke requires
immediate medical help. Even if the ultimate diagnosis
is not stroke, many diseases that can mimic a
stroke are also medical emergencies.
If a physician cannot be contacted by telephone,
the person should be taken to the nearest hospital
emergency department at once. Many types of stroke
require immediate treatment, and most of the promising
new therapies for stroke are effective only if
started within a few hours of the onset of symptoms.
A variety of diagnostic tools are available to the
physician, from history-taking and trained observation
to sophisticated radiologic imaging studies. The
tests performed will vary with the type of stroke, its
severity, and the planned therapies. Regardless of the
tests used, the goals are the same: to exclude nonvascular
reasons for the neurological symptoms and
to pinpoint the cause, location, and extent of the
stroke.
HISTORY AND EXAMINATION
Perhaps the most important diagnostic tool is the initial
history and physical examination of the patient.
Critical details about the medical history may have to
be obtained from a family member if the patient is
disoriented or unable to speak.
During the examination, the physician will test a
variety of neurological functions: orientation, memory,
emotional control, motor skills, tactile sensation,
hearing, vision, and the ability to read, write, and
speak. Using knowledge of brain anatomy and function,
a neurologist can usually identify the area of the
brain that is damaged by noting the specific symptoms.
For example, difficulty with walking and balance
is likely due to damage to the cerebellum.
Specific deficits on one side of the body point to damage
in the opposite cerebral hemisphere.
The general examination should also include a
search for evidence of high blood pressure, coronary
heart disease, or disease in other parts of the vascular
system. Using findings from the history, neurological
examination, and general examination, the physician
will formulate an initial opinion about the location
and type of stroke. Laboratory and radiological tests
will then be ordered to help confirm or exclude the
physician’s initial suspicions.
LABORATORY TESTS
Tests are usually done on samples of blood, urine,
and, occasionally, cerebrospinal fluid (fluid around
the brain and spinal cord). They focus initially on excluding
conditions that can mimic or worsen a stroke,
such as infection or low levels of blood sugar. Screen-
STROKE
ing may also be done for diabetes, elevated blood
cholesterol, bleeding disorders, and abnormalities in
blood proteins—risk factors for cardiac disease and
recurrent stroke.
IMAGING STUDIES
Computed tomography (CT) scans and magnetic resonance
imaging (MRI) are techniques that produce
anatomic pictures of the brain. Computed tomography
scans use multiple X-rays and computer reconstruction
to create cross-sectional images of internal
structures. Magnetic resonance imaging uses magnetic
fields to create images. Each has advantages in
different circumstances. Because these scans can delineate
(and thus help exclude) such conditions as tumors,
abscesses, and bleeding from trauma, they are
often done early after a stroke. They can usually differentiate
ischemic strokes from those that are due
to bleeding.
The studies are often repeated several days after
the onset of a stroke to determine its size and because
the full extent of the damage may not be seen until
then. If a patient’s condition worsens, the tests may
be repeated in order to help determine the cause of
the deterioration.
Magnetic resonance devices are also capable of
spectroscopically (based on spectrums of light) measuring
chemicals within the brain. These measurements
may be important in determining the
mechanism of a stroke and the prognosis and best
therapy for a particular stroke victim.
CARDIAC EVALUATION
An electrocardiogram (ECG) is usually the first step
in a cardiac evaluation. An ultrasound examination
(echocardiogram) of the heart may help pinpoint a
source of an embolus.
ANGIOGRAPHY
Angiography involves the injection of a dye or contrast
medium into an artery in order to study the
blood vessels via X-ray pictures. It can be used to
detect many of the abnormalities that cause stroke,
including narrowing or occlusion of a blood vessel,
embolus, atherosclerosis, dissections, arteriovenous
malformations, and aneurysms.
Because angiography is an invasive technique, in
that it introduces instruments and substances into the
body, it may be associated with serious complica-
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MAJOR CARDIOVASCULAR DISORDERS
tions. These include inducing or worsening a stroke,
allergic reactions to the contrast medium, and, very
rarely, death.
Newer techniques using magnetic resonance imaging
can be used to produce an angiogram noninvasively.
As these images continue to improve in
quality, they may replace conventional angiography.
ULTRASOUND
Ultrasound is a noninvasive technique that uses
sound waves and their echoes to visualize structures
and blood flow within the body. Two types of ultrasound
are used in stroke diagnosis carotid ultrasound
(to measure flow in the carotid arteries) and
transcranial Doppler (to measure flow in the intracranial
arteries). Although the anatomical information
it produces is not as precise as that obtained
through angiography, ultrasound has the advantages
of being painless and risk-free. It is often used to
screen patients before invasive studies are done.
BLOOD-FLOW STUDIES
Blood-flow techniques-such as positron emission
tomography (PET), single-photon-emission computed
tomography (SPECT), and xenon inhalation—
provide information on blood flow in the brain. These
tests may show changes immediately after the onset
of stroke symptoms, while computed tomography or
magnetic resonance imaging may remain negative
for several hours or days after a stroke.
The role of these tests is still being defined, and
they are generally available only in large medical centers.
They may be useful in determining the mechanism
of a stroke (e.g., carotid stenosis) or determining
prognosis early in the hospitalization.
STROKE TREATMENT
The primary goals of stroke treatment have changed,
thanks to new drug therapy. Doctors now attempt to
halt the progression of the stroke and to prevent
recurrence. In years past, when it was believed that
all brain cells died after about four minutes without
blood flow, stroke was considered to be largely untreatable.
Spurred on by observations in animals that
at least partial recovery can occur after even an hour
of complete ischemia (lack of oxygen), researchers
have discovered that regions of the brain with very
minimal blood flow can survive-although they do
not function normally-for several hours or perhaps
days. These viable cells surrounding an infarct, called
the “ischemic penumbra," are the focus of numerous
experimental drug therapies aimed at restoring blood
flow or preserving cell function.
As researchers learn more about the mechanisms
of stroke, they are realizing that it is not simply a lack
of blood flow that causes death of tissue; a progression
of other processes (including inflammation and
toxic buildup), called the ischemic cascade, may play
an even greater role in causing lasting necrologic
damage. Doctors believe that if they can interrupt this
cascade, they may be able to prevent the devastating
brain damage that was once the inevitable consequence
of stroke.
TREATMENT OF ACUTE STROKE
Most treatment of stroke during the acute phase centers
on maintaining fluids and electrolytes (chemical
substances in the blood, such as sodium and potassium),
avoiding low blood pressure (hypotension),
and avoiding the secondary complications of stroke
and paralysis. The latter includes pneumonia, urinary
tract infections, muscle contractures, and pressure
breakdown of the skin (bedsores). The physician will
also attempt to anticipate and avert deterioration after
a stroke. This will require constant monitoring
and evaluation and may necessitate a number of laboratory
tests.
Anticoagulant medications such as heparin are
sometimes used to treat an acute ischemic stroke.
While heparin does not dissolve existing clots, it can
prevent the formation of new ones. Thus it may help
prevent subsequent strokes, which occur in up to 20
percent of ischemic stroke cases.
Because heparin can increase some patients’ tendency
to bleed, its use is often restricted to those with
the highest risk of recurrent stroke: patients with a
progressing stroke, more than one TIA, or a cardiac
source of embolism (often seen with myocardial infarction,
atrial fibrillation, or valvular diseases). Related
drugs known as heparinoids are now being
evaluated and appear to be at least as effective, with
a lower risk of bleeding.
Surgery is usually not used to treat an acute stroke,
although it maybe indicated for a hemorrhagic stroke
(subarachnoid and brain hemorrhages) or a recent
blockage of a carotid artery.
LONG-TERM TREATMENT OF TIA AND STROKE
After the acute phase of a TIA or stroke has passed,
emphasis is placed not only on recovery and rehabilitation
but also on preventing further vascular
events, including ischemic stroke and myocardial infarction.
Therapy may include modification of risk
factors, drugs, or surgery, or a combination.
Risk factors are discussed earlier in this chapter.
Treatment of high blood pressure and diabetes, along
with smoking cessation, are probably the most important.
The effects on stroke risk of modifying other
factors–controlling weight, lowering cholesterol,
and moderating alcohol intake—are not as well studied,
but these modifications are generally recommended.
Treatment of additional risk factors is best
considered on an individual basis in consultation with
a physician,
ANTIPLATELET MEDICATIONS
Platelets are cell fragments that circulate in the blood
and play a key role in the formation of clots. Medications
that inhibit platelet function, such as aspirin,
lessen the tendency of blood to clot. Patients at high
risk of stroke are known to benefit in several ways
from taking aspirin daily. Aspirin therapy lowers the
risk of stroke and stroke-related death.
Unfortunately, aspirin therapy is complicated by
the fact that the optimal dose is unknown. If the dose
is too low, the aspirin will not have an effect on the
platelets; if it is too high, it may cause the blood vessel
walls to release chemicals, resulting in the formation
of more clots. Most authorities recommend between
325 and 1,200 mg aspirin per day (one to four tablets),
a higher dose than that usually recommended to prevent
a heart attack. More recent evidence suggests
that doses as low as 80 mg per day may also have a
protective effect.
Although aspirin has been shown to reduce the
risk of stroke, it may not’ be appropriate for all patients,
For example, it should not be used in patients
whose blood pressure is not normal. Before beginning
any treatment, even as simple as aspirin therapy,
a patient should consult his or her physician. Aspirin
should always be part of a larger program directed
at all aspects of vascular disease prevention.
Ticlopidine, a relatively new antiplatelet medication,
appears to be about 15 percent more effective
than aspirin in reducing the risk of stroke in people
who have had a TIA or minor stroke. This slight improvement
in efficacy must be weighed against more
serious side effects such as rash, diarrhea, and lowered
white cell counts, and higher cost.
ANTICOAGULANTS
Like antiplatelet medications, anticoagulant drugs
also interfere with the clotting mechanism, in this
case by affecting the action of enzymes necessary for
clotting. A commonly used anticoagulant is warfarin
(Coumadin). Because it is a more powerful drug than
aspirin, it is usually recommended only when aspirin
therapy has failed or when it is clear that the source
of the clots is the heart (e.g., when the patient has
atrial fibrillation or has had a myocardial infarction
or valvular heart disease).
Patients taking warfarin must be carefully monitored
via periodic blood tests, known as prothrombin
time tests, that measure the speed of clotting. Without
monitoring, the dosage may be too low, increasing
the risk of stroke, or too high, increasing the risk of
bleeding complications. Patients also need to be
aware that certain medications and foods (leafy green
vegetables such as spinach and other foods high in
Vitamin C) can alter the effectiveness of warfarin.
However, dietary restrictions are not usually advised
for patients on anticoagulants.
SURGERY
The goal in surgery is to provide a pathway for blood
to get to the brain. This is most commonly done using
a procedure known as carotid endarterectomy, in
which a stenosis (narrowing) or ulceration of an atherosclerotic
plaque in the carotid artery is removed.
Similar interim results were released in 1991 from
two large studies of carotid endarterectomy. Participants
in the study had experienced either a recent
TIA or a nondisabling stroke, and each had a carotidartery
blockage of more than 70 percent. Participants
who underwent endarterectomies showed a sixfold
reduction in strokes, compared to those who did not
have surgery. This dramatic result suggests that carotid
surgery is likely to play a key role in the prevention
of recurrent stroke in the coming years.
There are, however, several important points that
should be made in interpreting these results. First,
the carotid narrowing must be in a particular portion
of the artery. For example, if a patient has a small
stroke in the left brain hemisphere, this is not an indication
for surgery on a narrowed right carotid artery.
Secondly, these studies were carried out at
leading medical centers that have low complication
rates. Thus, the results suggest that carotid surgery,
in the best of circumstances, reduces the risk of
stroke. Whether this will hold true for all hospitals
remains to be demonstrated. Finally, as physicians
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MAJOR CARDIOVASCULAR DISORDERS
better understand stroke risk factors, it maybe possible
to use even more precise criteria to select patients
for surgery. For example, even considering the
group of people with the most severe carotid narrowing,
there are many who will not have a stroke.
Using risk stratification models and blood flow measurements,
it maybe possible to identify people who
do not require surgery, even though they may have
a carotid-artery blockage of more than 90 percent.
Despite the encouraging results of these two studies,
there are still no answers for people with a carotid
artery narrowing of less than 70 percent or for those
who have not yet had a stroke or TIA. These questions
are being investigated actively in clinical studies, and
results should be available in the next few years.
Although conceptually appealing, the removal of
a carotid stenosis is not without risk: There is a 10
percent complication rate across the United States.
There is evidence to suggest that only medical centers
where the complications and mortality rates are less
than 6 percent should be performing the procedure.
Another way of providing blood to the brain is via
a procedure known as extracranial-intracranial bypass,
which involves connecting an artery from the
scalp to one on the surface of the brain through a
surgical opening in the skull. This procedure was recently
tested in a large cooperative trial and was not
demonstrated to be beneficial; it is not recommended
at this time.
RECOVERY FROM A STROKE
Recovery after a stroke is dependent on many factors:
the specific site of the brain injury, the general health
of the patient, his or her personality and will, family
support, and the care received. The best recovery is
usually seen in a patient who has had a small ischemic
stroke. Large subarachnoid hemorrhages pose the
most difficult challenge for recovery. Nevertheless,
there are few solid rules for prognosis, and each case
should be considered on an individual basis.
Caring for a patient after a stroke is a multifaceted
and often complex process. The care must include
helping the patient recover from deficits (such as
weakness of an arm or leg or an inability to speak
clearly) and learn to function with any losses, dealing
with the patient's emotional issues and those of the
family, and preventing recurrent strokes.
REHABILITATION
In the immediate poststroke period, medical personnel
care for the patient’s physical needs in order to
reduce the risk of complications. Patients who have
difficulty swallowing, for example, may need to be
fed intravenously until they are able to swallow water
and food adequately. Most patients will be able to get
out of bed for increasingly longer periods within two
to three days and be able to leave the hospital in ten
days to two weeks.
Planning for rehabilitation should begin as soon
after the stroke as possible. Early attention to weak
limbs can greatly improve the chances of a successful
recovery. Simple measures such as frequent position
changes while in bed and exercise of the paralyzed
areas (including moving the arms and legs by physical
therapists, nurses, and family members) can improve
the circulation, maintain joint flexibility,
maintain normal muscle tone, and get the family and
patient involved in the recovery process. Physical
therapy generally starts within four or five days after
the stroke.
The rehabilitation process becomes more active as
the patient becomes medically stable (usually within
a day or two). Passive range-of-motion exercises, in
which a family member, nurse, or physical therapist
performs most of the movement, are replaced by active
range-of-motion routines, in which the patient
strives to regain strength in the affected limbs.
The efforts of the rehabilitation team also must
focus on the mental aspects of recovery-not only to
help patients overcome deficits in knowledge or
memory, but also to help prepare them for the long
recovery process and encourage them to lead lives
as full as possible with the abilities they retain. It is
important to keep in mind that many people have
fought their way back from a stroke and continued
to lead useful and fulfilling lives. Patients with the
ability to make decisions should be included in family
decision-making.
No program can succeed without a strong desire
by the patient to be independent. Nevertheless, family
involvement is also a key ingredient in a successful
rehabilitation program. The family can provide a positive
environment for the patient, nurturing the desire
to be independent while reassuring the patient that
he or she is still wanted, needed, and loved. Often
giving a patient something to do, and to live for, is
half the battle.
The family is also important because although
most patients are able to leave rehabilitation facilities
to return to their families, often they continue to have
Possible Consequences of
Left- and Right-Brain Injury
Damage to the left side of the brain
Right-side paralysis
Speech and Ianguage deficits
Slow, cautious behavior
Memory problems related to language
Right-side neglect (less common than left-side;
see below)
Damage to the right side of the brain
Left-side paralysis
Spatial-perceptual problems
Left-side neglect
Quick, impulsive behavior
Memory problems related to performance
some problems and their recovery process must continue
at home. Family members should take as much
of the responsibility for physical therapy at home as
is practical. A nurse or physical therapist visiting the
home for a few hours a week cannot alone provide
the sustained encouragement and the level of activity
needed to facilitate recovery.
Beyond the patient and family, rehabilitation is a
team effort with input from physiatrists (rehabilitation
physicians), neurologists, nurses, physical therapists,
occupational therapists, speech therapists,
and social workers. Their common goal is to help the
patient and family achieve the maximal level of functioning
possible.
Most stroke patients will need several types of
therapy, described below, but the mix and amount of
each will be tailored to the patient’s needs and symptoms.
Although symptoms of brain damage vary
widely, some generalizations can be made. A common
way of characterizing stroke injury is by the side
of the brain affected. An injury to the right side of
the brain that results in paralysis—temporary or
permanent—will affect the left side of the body. Conversely,
right-sided paralysis is the result of injury to
the left side of the brain. Certain language problems
and changes in behavior are also associated with leftor
right-side damage. (See box, “Possible Consequences
of Left- and Right-Brain Injury.”)
PHYSICAL THERAPY
The primary objective of physical therapy is to help
patients who are partially paralyzed learn to walk
again. Starting slowly, the therapist will first work
with the patient on simple exercises to increase range
of motion and muscle tone. Once the patient is able
to turn over and sit up unsupported, the therapist
usually will have the patient try to start walking. A
patient learns to walk while holding on to a bar for
support, and then with the aid of a quadruped cane
(one with a sturdy four-footed base) and, usually, ankle-
foot braces for stability. An estimated 75 percent
of all stroke survivors are eventually able to walk independently
and will regain most of their ability by
the end of the first month.
OCCUPATIONAL THERAPY
Although the ultimate goal is to help the patient resume
some sort of employment, if possible, occupational
therapy encompasses all aspects of everyday
life. Occupational therapists help patients regain the
muscular coordination necessary to perform basic
activities such as dressing, bathing, and using the
toilet. A patient who is paralyzed on one side is taught
how to maneuver clothing using the able side of the
body, and is advised about clothing styles-such as
pullover rather than buttoned shirts-that are easiest
to maneuver. Patients are taught how to use a wheelchair,
and how to transfer from bed to wheelchair
and vice versa. The occupational therapist will also
advise the family about changes that can make a patient’s
move back home easier and safer: handrails in
the bathtub and by the toilet, a raised toilet seat, and
ramps in place of stairs, and widened doorways to
accommodate a wheelchair, if one is still necessary.
SPEECH THERAPY
Two disorders that may occur after a stroke are
aphasia (difficulty with language) and dysarthria (difficulty
with articulation). Aphasia and dysarthria are
not necessarily associated with a loss of the ability to
think or understand.
Dysarthria is caused by weakness or paralysis of
muscles in the face, mouth, neck, or throat. It can
result in slow, labored speech, slurring of words, or
a change in voice quality. Often the paralysis of the
face muscles causes drooping of one side of the face
and perhaps drooling.
Most stroke patients with left-brain injury have
some degree of aphasia. It manifests itself in different
ways in different patients; there may be difficulty
making oneself understood, comprehending others’
words, or reading, writing, or doing arithmetic. The
complexity of the problem mirrors the complexity of
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MAJOR CARDIOVASCULAR DISORDERS
the communication process, which involves on the
one hand organizing thought, finding the words to
express it, and producing the words, and on the other
hand perceiving that someone wants to say something
to you, following the words as they are spoken,
and then comprehending the message in its entirety.
Aphasia may be equally frustrating for the patient
and the family and friends, who may feel they can no
longer communicate with the patient. Imagine waking
up into a world where you mean to say one thing
and something completely different comes out of
your mouth, or one where your family seems to be
speaking a foreign language that you cannot comprehend.
This is what an aphasic patient may experience.
But with the help of a speech therapist and a
cooperative family, a stroke survivor has an excellent
chance of regaining communication skills. If the patient
is not able to produce speech specifically, that
does not mean he or she cannot use and comprehend
language in the larger sense of the word, which encompasses
other communication tools such as gestures,
movements, facial expressions, and noises.
A speech therapist should lay the groundwork
while the patient is in the hospital, first working to
obtain from the patient reliable (verbal or nonverbal)
yes or no responses to questions. Then the therapist
uses a variety of techniques, including repetition and
pointing to pictures, to reestablish the fundamentals
of language. In most cases, the knowledge of language
hasn’t been eradicated, and patients just need
to regain their ability to recall what they have learned
in the past. As with other memory losses, the patient
will often regain ability to remember events that happened
in the distant past, but will not be as able to
remember things that happened in the very recent
past—where he or she left a hat ten minutes ago.
ADJUSTING AFTER A STROKE
Rehabilitation may continue on an outpatient basis
after the patient has returned home, and recovery
may continue for months or even years. The most
dramatic changes occur in the first three to six
months or so; smaller changes may continue for long
afterward.
There are no clear guidelines for how much activity
benefits stroke patients and how hard to push
them. They should be pushed hard enough to be challenged,
but not so hard as to be continually frustrated.
Recovery from a stroke can be a painfully slow process.
Both family and patient should take time to note
successful efforts, and family members need to offer
positive feedback, encouragement, and praise.
The stroke does not just happen to the patient-it
happens to the family as well. Understanding how
strokes can affect patients will make it easier for families
to deal with the recovery process. Some of the
major behavioral, cognitive, and emotional effects
are discussed below.
APHASIA
The lack of ability to communicate may sometimes
improve rapidly—within a few days or a week—but
in many cases, recovery is a long process. The recovering
aphasic patient needs stimulating and understanding
companionship. In addition to helping
these people feel loved and supported, engaging
them in conversation and activity reinforces language
skills. A patient who is left alone with little to do will
progress much more slowly than one who is made
to feel a part of the family, or has simple, arousing
things to do, such as looking through a picture
magazine.
Just as parents can grasp what toddlers mean
when they gurgle or grunt or use made-up words,
family members can often learn to understand the
patient’s limited, disjointed, or inappropriate speech
during the first few weeks after the stroke. Patients
may say “car” when they mean “couch,” and may
not realize that they are not being understood. They
may use swear words that they never uttered before
the stroke, or repeat the same word over and over.
Family and friends can learn to speak slowly, use
simple words and short sentences, and repeat them
if necessary. A variety of computer software designed
to help in language retraining is now available,
It is important for the family and friends neither
to overestimate nor underestimate what the recovering
patient understands. If the patient says yes or
smiles and nods in agreement with something that is
said, he or she may be responding to the speaker’s
facial expression or expressing pleasure about being
spoken to. A speaker who consistently overestimates
what the patient understands will become annoyed
that the patient doesn’t follow through and may decide
that the patient is forgetful or uncooperative. Or
the speaker may talk too much, thus overloading the
patient and interfering with any understanding the
patient may have. Unrealistically high expectations
about what the patient should be able to do can be
STROKE
very frustrating for both patient and family. On the tious, and disorganized when faced with an unfaother
hand, if the patient's cues that he or she does
understand are missed, family members are less likely
to continue to engage the patient in communication,
which can have devastating effects on emotions and
recovery. To avoid either extreme, family members
need to be sensitive to nonverbal cues as well as verbal
responses and to test understanding occasionally
by saying something improbable and noting the patient’s
response. (See box, “Tips on Communicating
with Stroke Survivors.”)
OTHER NECROLOGIC DEFICITS
Family members can also help lessen the impact of
other necrologic-behavioral changes. If patients have
difficulty remembering recent events, it is important
to remind them of their recent successes in regaining
functions. Patients with left-brain damage (with or
without right-sided paralysis) are often slow, caumiliar
situation-even if their behavioral style was
quite different before the stroke. Family members can
help the patient by giving positive feedback for things
done correctly. Patients with right-brain damage, on
the other hand, tend to act impulsively and hastily;
they are often poor judges of their own abilities and
safety. Family members can help by reminding patients
to take things slowly and carefully.
Some stroke patients suffer a loss of half of their
visual field in each eye. Some patients, particularly
those with right-brain damage, also have one-sided
neglect: they do not compensate for their visual loss
by turning their heads. Rather, they ignore everything—
including objects and even sensations—on
the side of the body where vision is impaired. Often
a patient will not even recognize an arm or leg as
being part of his body. People may have to approach
patients from their unimpaired side in order to be
noticed. Putting objects on the patient’s good side—
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MAJOR CARDIOVASCULAR DISORDERS
—
such as clothes only on one side of the closet—can
make management easier.
Deficits in spatial relations-judging the size, position,
distance, or speed of objects, for example—
are common among people with right-brain damage.
This can create problems for self-care, making it difficult
for a person to button a blouse correctly, steer
a wheelchair without bumping into obstacles, read a
newspaper without losing his or her place, or even
sip soup from a spoon.
Other common, but not universal, problems that
may occur following a stroke include:
Poor concentration
Poor judgment of time
Disturbed sleep cycles
Impaired memory
Impaired judgment
Loss of sexual desire
Poor emotional control
Depression
EMOTIONAL IMPAIRMENT
Often families and patient focus on the physical impairments
after a stroke. These are readily apparent
and easily understood. But the brain is also responsible
for our thoughts and emotions. It is this aspect
of damage after a stroke that is often the most difficult
to deal with.
People who have recently suffered a stroke may
have a loss of emotional control because of damage
in the area of the brain that controls emotions. As a
result, they may cry or laugh suddenly, often inappropriately,
at times when they do not feel especially
sad or happy. Some patients may become irritated
and express anger with little provocation. Simply distracting
the patient can often interrupt the emotional
behavior.
On the other hand, true depression is not uncommon
in stroke patients, whose lives have been
changed drastically and who feel discouraged or
hopeless. In part this can be a natural reaction to a
devastating disease and the often slow and difficult
recovery process. Often it is also caused by damage
to areas of the brain and by neurochemicals responsible
for mood and motivation. Signs of depression
include excessive crying (which cannot be easily interrupted],
fatigue, sleep and eating disorders, and
loss of interest in activities. Support from family
members and an emphasis on the positive progress
that has been made—without ignoring the existence
of deficits-can be helpful. Antidepressant medications
can be prescribed for patients whose downheartedness
is hampering their progress.
Problems such as sexual dysfunction, loss of self-
-esteem, and difficulties in family relationships are
best dealt with openly and with the help of trained
medical personnel. These are important issues for
quality of life following a stroke and should not be
ignored. The important thing to remember is that
many of these conditions can be helped. Sometimes
just the knowledge that this is a common problem
and that it is often self-limited is enough to get the
patient and family back on track. In more serious
cases, therapy (personal or family) and medications
may be necessary. The key is to speak frankly and
keep the physician and other health care personnel
informed.
PHYSICAL ACCOMMODATIONS
Planning for returning home after a stroke may require
some physical adjustments in the house. Many
of these are simple and can be done by the family
(rubber shower mats, soap enclosed in a cloth pouch
to avoid slipping, handgrips, and removal of small
scatter rugs); others may require more detailed planning
and construction (ramps, lowered counters,
high toilets, changing the height and location of light
switches). Useful devices such as one-handed card
holders, rocker knives, nonskid mixing bowls, and
modified telephones can be purchased, often through
specialized catalogs. These modifications are best
planned in conjunction with occupational therapists
and by sharing experience with other families
through local support groups, such as stroke clubs.
TOWARD THE FUTURE
Several exciting approaches to stroke therapy are under
investigation. All are in, or near, clinical testing
in humans.
One investigational approach is thrombclytic
therapy—the use of drugs such as t-PA {tissue plasminogen
activator) to dissolve a clot and reopen the
occluded vessel causing the stroke. This therapy has
already proved successful in treating heart attacks
and shows promising early results in stroke patients.
The major drawback is an increased risk of bleeding.
Another approach is to route blood flow around
the occlusion through small collateral vessels, after
making these vessels larger by, for example, using
vasodilating agents such as calcium channel blockers.
An alternative is to lower the viscosity (thickness) of
the blood (by, for example, adding plasma expanders)
in order to make the flow through the small vessels
easier.
Researchers are also attempting to determine the
chemical reactions that lead to permanent damage
during a stroke. Once these are understood, it
may be possible to inhibit these harmful reactions
selectively and lessen the damage. Calcium-channelblocking
drugs, already being used to treat other cardiovascular
conditions, may help reduce the damage
caused by a stroke.
Other drugs being investigated also work to protect
the nerve cells. These include the NMDA-receptor
blockers.
One of the newest areas of investigation is restorative
neurology, which studies how the brain and
nerves repair themselves after injury. Current medical
wisdom says that in adults, nerve cells do not
divide in order to create new cells, so that damaged
brain cells cannot be replaced. This maybe only partially
true. While cell regrowth is not yet possible, it
may be possible to influence how neurons communicate
with each other after injury.
STROKE
Nerve cells are “connected” to thousands of other
nerve cells through connections called synapses,
which change after injury to the brain. It appears that
gangliosides, a class of molecules on the surface of
neurons, help new synapses form. By giving stroke
patients extra amounts of gangliosides, it may be possible
to increase the number of synapses, permitting
the brain to develop a wider variety of compensatory
brain circuits and minimize the deficits. This therapy,
now in clinical trials, would not change the size of the
stroke, but could improve outcome for the patient.
SUMMARY
Neurology is on the verge of major breakthroughs in
stroke treatment that hold promise for being able to
drastically reduce the effects of stroke. But despite
advances in treatment, prevention remains the most
effective way of decreasing the national burden
caused by strokes. Patients at risk must work with
their doctors to reduce their likelihood of falling victim
to a disabling stroke. Life-style changes and better
management of high blood pressure have already
been responsible, along with better treatment of
strokes when they do occur, for a more than 50 percent
decrease in stroke deaths over the past 20 years.
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