Report On Stroke

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Chapter – 1


of the study

Stroke is a sudden loss of brain
function caused by the interruption of blood flow to the brain. Stroke is a
leading cause of disability worldwide. Hippocrates first described the sudden
paralysis that is often associated with stroke. The word stroke was used as a
synonym for apoplectic
seizure as early as 1599, and is a
fairly literal translation of the Greek term. In 1658, in his Apoplexia,
Johann Jacob Wepfer (1620–1695) identified the cause
hemorrhagic stroke when he suggested that
people who had
died of apoplexy had bleeding in
their brains. Wepfer also identified the main
supplying the brain, the
vertebral and carotid
arteries, and identified the cause of
stroke (also known as
cerebral infarction) when he suggested that apoplexy
might be caused by a blockage to those vessels.


Stroke or cerebrovascular
accident (CVA) also called brain attack, is a brain injury caused by a sudden
interruption in the blood supply of the brain. It occurs when part of the brain
does not receives the needed blood flow for one of two reasons: 1) either the
blood supply to part of the brain is suddenly interrupted, or 2) because a
blood clot blocks a blood vessel or artery, or when  a 
blood vessel  in the brain
ruptures and blood invades the surrounding areas. As a result, the affected
area of the brain cannot function, which might result in an inability to move one or more
limbs on one side of the body
inability to
understand or formulate speech, or an inability to see
one side of the visual field
A stroke is a
medical emergency and can cause permanent neurological damage, complications, and
death. The traditional definition of stroke, devised by the
World Health
the 1970s, is a “neurological deficit of cerebrovascular cause that
persists beyond 24 hours or is interrupted by death within 24 hours”

of stroke

Stroke is one of the leading causes of long term disability,
and of death, in the developed world. Approximately 700,000 Americans per year
experience a stroke. It is the third leading cause of death and the leading
cause of long-term adult disability in the United States. According to the
World Health Organization (WHO) 15 million people suffer from stroke worldwide
each year. On average, a stroke occurs every 45 seconds and someone dies from a
stroke every 3 minutes. Asymptomatic infarctions, usually lacunar, are present
in 7% of MRI scans; 2% of scans detect incidental intracranial
. Risk
factors for stroke include
atherosclerosishypertensiondiabetes mellitushigh cholesterolcigarette
atrial fibrillationmigraine headaches ethnic identity, and some blood clotting disorders.

of stroke

1:  This is an x-ray image of the head
after a radio-opaque dye was injected into the arterial system; the image is
called an

The brain is made out of nerve cells and supporting cells, it
is covered by protective layers and it is moistened by the constant circulation
of a pristine fluid called “cerebrospinal fluid” (CSF). Like all parts of the
body, the brain has vessels that pump blood to it from the
heartarteries and vessels that collect the blood after circulating through
the organ for return to the heart called
veins. As in most organs of the body, the
arteries to the brain carry blood loaded with oxygen and glucose (blood sugar)
and the veins carry away blood that has delivered these vital supplies to the
cells of the brain and had their waste products dumped in it.

There are special features of the vasculature to the brain
that are protective since brain cells are more vulnerable to loss of oxygen and
glucose than are the cells of any other portion of the body. One of these
features is the circular design of the blood delivery system to the brain. This
circle of arteries that joins blood pumped up from the front of the neck ( the carotid arteries) from blood
pumped up from the back (the vertebral arteries). In most healthy young people,
this system of blood flow is so good that even if one of the arteries is lost
altogether (from an injury, for example), the others can make up for it and
keep delivering a properly working circulation of fresh arterial blood, and no
impairment to the brain cells occurs.

1.5 Classification of

are three types of stroke .Such as

1. Ischemic stroke.

2. Hemorrhagic

3. Transient ischemic attack (TIA).

Ischemic strokes are those that are caused by
interruption of the blood supply. Ischemic
is the most common type of stroke, and it accounts for
83 percent of all strokes. An ischemic stroke occurs when the blood vessel
(usually an artery) supplying blood to a part of the brain is blocked by fatty
deposits or a blood clot. In an ischemic stroke, blood supply to part of the
brain is decreased, leading to dysfunction of the brain tissue in that area. There
are four reasons why this might happen:

(obstruction of a blood vessel by a blood clot forming locally)

A cerebral
(embolic stroke) -the blockage is caused by a blood
clot, air bubble, or fat globule that forms in a blood vessel somewhere in the
body, and it travels through the bloodstream into the brain.

hypo perfusion (general decrease in blood supply, e.g., in

blockage occurs in the tiny blood vessels deep within the brain.

2: A slice of brain from the autopsy of a person who suffered an acute
middle cerebral
artery (MCA)


There are various classification systems for acute ischemic
stroke. The Oxford Community Stroke Project classification (OCSP, also known as
the Bamford or Oxford classification) relies primarily on the initial symptoms;
based on the extent of the symptoms, the stroke episode is classified as total
anterior circulation infarct
anterior circulation infarct
lacunars infarctposterior
circulation infarct

(POCI). These four entities predict the extent of the stroke, the area of the
brain affected the underlying cause, and the prognosis. The TOAST (Trial of
Org 10172 in Acute Stroke Treatment) classification is based on
clinical symptoms as well as results of further investigations; on this basis,
a stroke is classified as being due to (1) thrombosis or embolism due to
atherosclerosis of a large artery, (2) embolism of cardiac
origin, (3) occlusion of a small blood vessel, (4) other determined cause, (5)
undetermined cause (two possible causes, no cause identified, or incomplete

Figure 3: Hemorrhagic Stroke and Ischemic stroke

are the ones which result from
rupture of a blood vesselHemorrhagic
is a less common type of stroke, and accounts for 17
percent of all strokes. A hemorrhagic stroke occurs when a blood vessel in the
brain ruptures and the blood invades the surrounding areas. This type of stroke
can be caused by –

aneurism (a weakened
region of a blood vessels balloons out, and left untreated can burst) or

(a cluster of abnormally formed blood vessels
where one of the vessels bursts).

There are two types of hemorrhagic strokes:

Intracerebral hemorrhage, the blood vessel ruptures within
the brain.

Subarachnoid hemorrhage, the blood vessel bursts on the
surface of the brain, and it bleeds into the area between the brain and the

4: An intraparenchymal bleed (bottom arrow) with surrounding edema (top arrow)

Intracranial hemorrhage is the accumulation of blood anywhere
within the skull vault. A distinction is made between intra-axial
inside the brain) and
inside the skull but outside the brain). Intra-axial hemorrhage is due to
(blood in
the ventricular system). The main types of extra-axial hemorrhage are
epidural hematomaDura matersubdural hematomasubdural spacesubarachnoid
arachnoids materpia mater). Most of the hemorrhagic stroke syndromes have specific
symptoms (e.g.,
headachehead injury).

, is a minor or warning stroke. It occurs when the blood
supply to the brain is briefly interrupted. This stroke is similar with the
ischemic stroke, but its symptoms tend to disappear within the next 24 hours.
The obstruction (blood clot), that causes the transient ischemic attack, occurs
for a short time and tends to resolve itself in time. A mini-stroke last for a
few minutes up to a day and, in some cases, it can be accompanied by typical
stroke signs. Even if the symptoms disappear in a short time, a transient
ischemic attack is a strong indicator of a possible major ischemic stroke to

Signs and Symptoms of a Stroke

A stroke
often appears suddenly, without warning, and its effects on the body are immediate.
The common symptoms of a stroke, which appear afterwards, include:

numbness, weakness, clumsiness, or paralysis on one side of the body. An
example of this symptom can be a dropping arm or leg, eyelid, or dribbling
mouth. This is one of the most common and recognizable stroke symptoms. This
symptom affects only one side of the body and causes difficulties in
controlling the arm or leg. In the worst cases, the weakness or paralysis is
accompanied by muscle and joint stiffness.

confusion, slurred speech, trouble speaking, or understanding speech. This is
another common symptom in patients that had a stroke. This symptom also
includes difficulties reading and writing.

blurred vision or loss of sight in one or both eyes. The stroke can damage that
part of the brain that receives, processes, and interprets the information sent
by the eyes to the brain. This can lead to a variety of problems such as double
vision, or losing half of the vision field.

trouble walking, dizziness, loss of balance, or loss of coordination.

of balance or unsteadiness. This can be the result of damage in the part of the
brain responsible with the body’s balance, or as a result of paralysis when the
muscles become weak.

or difficulties swallowing is another common symptom in patients with stroke.
About 50 percent of those that have a stroke have swallowing problems.

and interpretation difficulties. People that suffered a stroke have
difficulties recognizing familiar objects or knowing how to use them.

processes impairment. After a stroke, the person can have problems thinking,
learning, remembering, concentrating, making decisions, reasoning, and

swings. People that suffer a stroke experience emotional ups and downs. They
can become depressed, sad, angry, anxious, experience low self-esteem and low

Associated symptoms

Loss of

symptoms are maximal at onset, the cause is more likely to be a subarachnoid
hemorrhage or an embolic stroke.

Causes of stroke

There are many different causes of stroke, but whenever a
stroke occurs, there has been an interruption of the normal blood supply to
brain cells that has gone on long enough to cause death to at least some of
them. If the loss is so brief that the brain tissue can quickly recover, and
does not die, then a Transient
Ischemic Attack (TIA)

has occurred, rather than a stroke. The symptoms and signs of a stroke are
highly dependent upon the number of cells that are affected, and exactly where
these cells are located in the brain. Accordingly, strokes can have many
different clinical presentations – ranging from deep coma with the loss of the
ability to breathe; to very limited deficits in the ability to move a part of
the body, or changes in sensory perception like partial blindness from a
restriction in visual field, without any associated problems with movement.

Ordinarily, at least some brain tissue is injured by a stroke
– yet not killed. The injury to these cells is reversible. That’s one reason
why the amount of recovery during the initial time period after a stroke is
difficult to predict, and also why treatment at that time can influence the
course of recovery. If the stroke patient survives the stroke, some brain cells
may actually recover in time if the injury was not too great.

Ten causes of stroke identified by researchers. Scientists
have found ten key health problems that cause almost all strokes.

blood pressure,


fat stomach,


of physical activity,

levels of bad cholesterol,


too much,

and depression and

disorders accounted for 90 per cent of strokes.

The research conducted by a team at McMaster University on
Ontario, Canada, is one of the most comprehensive looking into the causes of
stroke. The factor with the strongest link was high blood pressure which more
than doubled the risk of a stroke, they said. Around 150,000 people in Britain
each year suffer a stroke and there are 67,000 deaths. It is a leading cause of
disability. The study published in The Lancet and presented at The World
Congress of Cardiology in Beijing looked at 3,000 people who had a stroke and
3,000 similar people who had not suffered a stroke.

They were questioned

much exercise they did and

diets given a score according to how healthy they were and tests and
measurements were carried out by professionals.

Alcohol intake was categorized as never or former drinker,
moderate drinker of between one and 30 drinks a month, more than 30 drinks a
month and binge drinker who had more than five drinks in one day in the last
month. They were classed as physically active if they were involved in walking,
cycling, gardening, jogging, football or vigorous swimming for four hours a
week or more. The findings showed that current smokers doubled their risk of
stroke, poor diet increased the risk by 35 per cent, 30 or more drinks a month
or binge drinking increased the risk by half, stress raised the risk by 30
percent and depression by 35 per cent. Being active reduced the risk by about
30 per cent. Martin O’Donnell, lead author said: “Our findings suggest
that ten simple risk factors are associated with 90% of the risk of ischemic
and intracerebral hemorrhagic stroke worldwide.”Targeted interventions that
reduce blood pressure and smoking, and promote physical activity and a healthy
diet, could substantially reduce the global burden of stroke.”Andrea Lane,
Spokesperson for The Stroke Association said: “Over the years there have
been a number of research studies into the causes of stroke, which have
identified a number of major risk factors.”This is an extensive and in-depth
study and so it’s great to see that the findings support previous research and
reflect the preventative advice provided by The Stroke Association.”

Effects of Strokes

The most common problems in daily life are likely to be
caused by:

or lack of movement (paralysis) in legs and/or arms



to way things are seen or felt (perceptual problems)

to the way things are felt when touched (sensory problems)

thinking or remembering (cognitive problems)

speaking, reading or writing,



controlling feelings,


The specific abilities that will be lost or affected by
stroke depend on the extent of the brain damage and, most importantly, where,
in the brain, the stroke occurred: the right hemisphere (or half), the left
hemisphere, the cerebellum or the brain stem. Each stroke is different and each
person that experiences a stroke is affected differently. Some stroke survivors
experience mild symptoms, while other faces severe and lasting damage. Once the
stroke occurs, the brain immediately undergoes changes. Without the blood
supply which provides the brain with nutrients and oxygen, the brain cells are
damaged and can die. Once dead, the cells cannot return to life, but the surrounding
areas can recover and take over or substitute some of the lost functions.
Usually, the recovery process happens in the first few months that follows the
stoke, but in some cases can continue for several years.

disability level differs from patient to patient, and depends on the type of
stroke suffered, the area affected, the location of the affected area, and the
extent of the damage. A stroke can occur in any part of the brain causing
damages according to those functions controlled by that area. Each part of the
brain is involved in different essential functions for the body. Usually, the
stroke symptoms and signs occur on the opposite side of the body to the stroke
side of the brain.

The human brain is divided in four main parts: (1) the right hemisphere,
(2) the left hemisphere, (3) the cerebellum, and (4) the brain stem. In most
people, the right hemisphere is responsible for perceptual and spatial skills,
the left hemisphere is responsible for language, the cerebellum controls
balance and coordination, while the brain stem controls those body functions
that do not require conscious control (such as breathing rate, blood pressure,
heart rate, eye movement, hearing, speech, and swallowing).

The effects of a stroke can be divided into two main categories:

(1) Body functions.

(2) Cognitive functions.

Effects of Right Hemisphere Strokes

The right hemisphere of the brain controls the movement of
the left side of the body so stroke in the right hemisphere often causes
paralysis in the left side of the body. This is known as left hemiplegic.
Survivors of right-hemisphere strokes may also have problems with their spatial
and perceptual abilities. This may cause them to misjudge distances (leading to
a fall) or be unable to guide their hands to pick up an object, button a shirt
or tie their shoes. They may even be unable to tell right side up from
upside-down when trying to read. Along with these physical effects, survivors
of right-hemisphere strokes often have judgment difficulties that show up in
their behaviour. They often act impulsively, unaware of their impairments and
certain of their ability to perform the same tasks as before the stroke. This
can be extremely dangerous. It may lead them to try to walk without aid or to
try to drive a car. Survivors of right-hemisphere strokes may also experience
left-sided neglect. This is a result of visual difficulties that cause them to
“forget” or “ignore” objects or people on their left side.
Some survivors of right-hemisphere strokes will experience problems with
short-term memory. Although they may be able to recall a visit to the seashore
that took place 30 years ago, they may be unable to remember what they ate for
breakfast that morning.

Effects of Left Hemisphere Strokes

The left hemisphere of the brain controls the movement of the
right side of the body. It also controls speech and language abilities for most
people. A left-hemisphere stroke often causes paralysis of the right side of
the body. This is known as right hemiplegic. Someone who has had a
left-hemisphere stroke may also develop aphasia. Aphasia is a catch all term
used to describe a wide range of speech and language problems. These problems
can be highly specific, affecting only one part of the patient’s ability to communicate,
such as the ability to move their speech-related muscles to talk properly. The
same patient may be completely unimpaired when it comes to writing, reading or
understanding speech. In contrast to survivors of right-hemisphere stroke,
patients who have had a left-hemisphere stroke often develop a slow and
cautious behaviour. They may need frequent instruction and feedback to finish
tasks. Patients with left-hemisphere stroke may develop memory problems similar
to those of right-hemisphere stroke survivors. These problems can include
shortened retention spans, difficulty in learning new information and problems
in conceptualizing and generalizing.

Effects of Brain Stem Strokes

Strokes that occur in the brain stem are especially
devastating. The brain stem is the area of the brain that controls all of our
involuntary functions, such as breathing rate, blood pressure and heart beat.
The brain stem also controls abilities such as eye movements, hearing, speech
and swallowing. Since impulses generated in the brain’s hemispheres must travel
through the brain stem on their way to the arms and legs, patients with a brain
stem stroke may also develop paralysis in one or both sides of the body.

Effects of Cerebellum Strokes

The cerebellum controls many of
our reflexes and much of our balance and coordination. A stroke that takes
place in the cerebellum can cause abnormal reflexes of the head and torso,
coordination and balance problems, dizziness, nausea and vomiting.

Effect of stroke on

Visual problems are more common in people who have suffered a
stroke affecting the right side of their brain. The damage the stroke does in
the brain impacts the visual pathways of the eye which can result in visual
field loss, blurry vision, double vision and moving images. When stroke affects
the areas of the brain that processes the information we see, it can cause
‘visual neglect’ (lack of awareness to one half of the body or space) as well
as difficulties with judging depth and movement. In a few cases, visual
problems caused by stroke can improve on their own with time.

Some of the vision problems that occur as a result of a
stroke include loss of part of vision or loss of visual field. Visual field is
the term used to describe the whole of our vision, from the centre to the
periphery. It refers to everything we can see in the periphery (around the
edges of our vision) as well as what we are directly looking at (central
vision). Strokes can cause whole sections of the visual field to be missing.
Other visual problems that may occur as a result of stroke include eye muscle
and nerve problems which can result in double vision and moving images as well
as other effects such as sensitivity to light.

Other Effects of Stroke

Depression is very common amongst people who have had a
stroke. It can be quite severe, affecting both the survivor and his/her family.
A depressed person may refuse or neglect to take medications, may not be
motivated to take part in physical rehabilitation or may be irritable with
others. This in turn makes it difficult for those who wish to help, and tends
to deprive the survivor of valuable social contacts that could help dispel the
depression. In time the depression may lift gradually, but counseling and
appropriate medication may be necessary. In the past, researchers speculated
that some of the older anti-depressant drugs might interfere with a person’s
mental performance but recent studies suggest that anything that can
effectively treat post-stroke depression, whether an old or new treatment, may
also improve mental ability and enhance rehabilitation.

Sudden laughing or crying for no apparent reason and
difficulty controlling emotional responses also affects many stroke survivors.
There may be little happiness or sadness involved, and the excessive emotional
display will end as quickly as it started. Apparent changes in personality
following a stroke may be very disturbing to the survivor’s family. Stroke
affected people may not seem the same person as before. The way in which they
think, feel and react may be altered. Problems and activities once tackled
easily may be difficult or impossible, while other tasks are unaffected.

The way in which the person affected by stroke reacts to
these changes will affect their personality, and may cause changes in control
of emotions and behaviour.  People affected by stroke may become confused,
self-centered, uncooperative and irritable, and may have rapid changes in mood.
They may not be able to adjust easily to anything new and may become anxious,
annoyed or tearful over seemingly small matters.

Complications after Stroke

Common complications of
a stroke:

  • Edema –
    brain swelling

Breathing food into the airway (



of mobility

of movement or feeling in one or more parts of the body

  • Muscle spasticityres – abnormal electrical
    activity in the brain, which causes convulsions
  • Clinical
    depression – a treatable illness that causes uncontrollable emotional and
    physical reactions to changes and losses
  • Bedsores –
    ulcers that result from a decreased ability to move
  • Limb
    contractures – shortened muscles in arms or legs that are caused by a
    reduced range of motion or lack of exercise
  • Shoulder
    pain – a consequence of lack of support or exercise of the arm
  • Blood
    vessel problems – formation of blood clots in the veins
  • Urinary
    tract infection and bladder control – urgency and incontinence
  • Pneumonia –
    results in breathing problems.


Pressure sores

speaking and understanding

Problems thinking
or focusing.

Chapter – 2

factors for stroke

Stroke risk factors are medical conditions or behaviors or
traits that make you more likely to develop a stroke. Having one or more risk
factors does not mean that you definitely will have a stroke, only that you are
more likely to do so. More than 750 thousand people suffer from stroke in the
U.S. each year, but up to 50% of strokes could be prevented. In the case of stroke,
many of the risk factors can be treated, modified or controlled. However, some
risk factors for stroke cannot be changed. Knowing ones risk factors is the
first step in preventing stroke. One can change or treat some risk factors, but
others can’t. By having regular medical checkups and knowing the risk, one can
focus on what can change and lower risk
of stroke.

Risk factors of stroke that can’t control

Age: The risk of stroke increases
with advancing age.

Ethnicity: People of First Nations,
African, Hispanic, and South Asian descent have greater rates of high blood
pressure and diabetes. These conditions increase the risk of stroke.

risk of stroke may be higher if a parent or sibling has had a stroke before the
age of 65.

In most age groups, more men than women have stroke, but more women die
from stroke. Men have a higher risk of stroke than women who have not reached

and race:
whose close blood relations have had a stroke have a higher risk of
stroke.  African Americans have a higher
risk of death and disability from stroke than whites, because they have high
blood pressure more often. Hispanic Americans are also at higher risk of

stroke or transient ischemic attack (TIA):
Someone who has had a stroke is at higher risk of
having another one. Up to one-third of people who survive a first stroke or TIA
will have another stroke within 5 years.

Risk factors of stroke that can control

(High blood pressure).

 Atrial fibrillation( an abnormal heart rhythm)


alcohol intake

unhealthy diet





Hypertension (High Blood

blood pressure is the most important
modifiable risk factor for stroke. The risk
of stroke increases 4 to 6 times when the person has high blood pressure. The
blood pressure measures the force of blood pushing against the walls of the
arteries. When the blood pressure is high, the heart has to pump harder to move
the blood through the body, which leads to weak blood vessels and damage to
major organs in the body. Normal blood pressure is 120/80 or below, whiles a
blood pressure reading of 140/90 and above is considered high blood pressure
(or hypertension).

fibrillation (an abnormal heart rhythm)

Fibrillation (AF) is a medical condition where the heart beats irregularly
because the two upper chambers of the heart beat rapidly and unpredictably.
Atrial fibrillation increases the risk of stroke up to 6 times because the
heart does not fully pump the blood out, which pools in the heart. When the
blood pools in the heart, the risk of blood clots forming is high. Once formed,
these blood clots will travel through the bloodstream into the brain
obstructing a blood vessel.


Tobacco use damages blood
vessels. Don’t smoke and avoid second-hand smoke. This can contribute to atherosclerosis and can also cause the blood vessels to constrict, which leads to
restrictions in blood flow. Smoking increases
the heart rate and blood pressure. The associated risk increases with the
number of cigarettes smoked per day, and passive smoking also increases this

 Excessive alcohol intake

It is thought that excessive alcohol intake may also increase
the risk of ischemic stroke by bringing about a rise in blood pressure. However, although drinking too much
alcohol is known to inflate the risk, people who consume moderate amounts (less
than 3 units per day) actually have a lower risk than those who do not drink at
all. This may be because moderate alcohol intake can improve blood lipid
levels, and so protect against vascular diseases such as stroke.

obese or overweight increases the risk of high blood pressure, high
cholesterol, diabetes, heart disease, which all increase the risk for stroke.
Unhealthy diet (including a low fruit and vegetable intake and a high salt

 High cholesterol

Cholesterol is a waxy, fat-like substance
produced by the liver and is used in different functions essential for the
body. If present in high amounts, cholesterol builds up in the veins and clogs
them (a condition called atherosclerosis). The build-up of plaque
inside the artery causes the walls to lose their elasticity and become weak and

Figure 5: Image of High Cholesterol


Diabetes is a medical condition where the body
either does not produce enough insulin, or the insulin is not properly used.
This disease is another major cause of stroke because the body can’t properly
process sugar (the basic fuel of the body’s cells) and fats. Diabetes also
leads to other medical complications such as high blood pressure, high
cholesterol, atherosclerosis, and obesity or excessive weight. Diabetes
interferes with the body’s ability to break down blood clots, which leads to an
increased risk of ischemic strokes. In general, those that suffer from diabetes
have a 2 to 4 times the risk of stroke than the non-diabetic population.

Physical Inactivity

In epidemiological studies comparing highly active to
sedentary individuals, physical activities are observed to reduce the risk of
both ischemic and hemorrhagic strokes. The 2008 Physical Activity Guidelines
for Americans concur in recommending regular physical activity to reduce
adverse health outcomes. In this guideline, most health benefits occur with at
least 150 minutes a week of moderate intensity, or 75 minutes a week of
vigorous intensity of aerobic physical activity. When adults with disabilities
are not able to meet these guidelines, they should engage in regular physical
activity according to their abilities, and they should avoid inactivity.
Exercise reduces blood pressure, decreases body weight, and improves other risk
factors, including metabolic syndrome the role of the health provider is
important and the physician’s advice regarding physical activity to patients
can significantly modify exercise and diet style, including those with a prior
stroke. One recent observation of note is associated with the onset of stroke
with physical activity. There might be an increased risk of stroke occurrence
within 1 hour of moderate or vigorous physical activity.

Drug abuse (certain kinds)

drug abuse carries a high risk of stroke from cerebral embolisms (blood clots).
Cocaine use has been closely related to strokes, heart attacks, and a variety
of other cardiovascular complications. Some of them, even among first-time cocaine
users, have been fatal.

 Cardiac structural abnormalities

heart valves can cause chronic heart damage, which can ultimately increase the
risk of developing stroke. This is known as valvular heart disease. New
evidence shows that heart structure abnormalities including patent foramen
ovale and atrial septal defect may possibly increase risk for embolic stroke.

2.3 Risk factors for Ischemic

In general, the risk factors for having an ischemic stroke – a stroke that is caused by a blockage in
an artery supplying the brain – may be
divided into those that can be modified (improved upon), and those that cannot,
as discussed below.Although some risk factors cannot be changed – for example,
a person’s gender or age – it is still important to be aware of them. This is
because people who have a number of unmodifiable risk factors may benefit from
making a greater effort to improve those risk factors that can be modified.In
addition to these risk factors, which are often classed as ‘traditional’, we
are also starting to learn about more recently identified risk factors.

Modifiable risk factors for Ischemic stroke

Fortunately, we do have control over many of the risk factors
for ischemic strokes. These include the following:

  • High blood pressure – the most important modifiable
    risk factor for stroke
  • Smoking –
    this can contribute to atherosclerosis
    and can also cause the blood vessels to
    constrict, which leads to restrictions in blood
    flow. The associated risk increases with the number of cigarettes smoked
    per day, and passive smoking also increases this risk
  • Excessive
    alcohol intake
  • Obesity,
    unhealthy diet (including a low fruit and vegetable intake and a high salt
  • Physical
  • Abnormal lipid levels (dyslipidaemia)
  • Diabetes mellitus (associated with
    stroke and other forms of vascular disease at a younger than average age)
    and metabolic syndrome
  • Carotid artery disease
  • Atrial
    fibrillation, an abnormal heart rhythm
  • Patent foramen oval (otherwise known as a ‘hole in
    heart’) – present in around 25 per cent of the general population, compared
    with 40 per cent of people who have had a stroke where no other cause is
  • Heart
    failure, endocarditis and other forms of
    heart disease
  • Oral
    contraceptives – thought to increase the likelihood of the blood to clot
  • Polycythaemia,
    a condition in which the red blood cell count is increased
  • Sleep
    apnoea, which causes interruptions in breathing while a person sleeps and
    appears to be associated with a higher risk of stroke and other
    cardiovascular diseases
  • Sickle cell disease, an inherited condition that
    results in the formation of abnormal, sickle-shaped red blood cells that can block small blood vessels, increasing the risk of an ischemic
    stroke. There is insufficient evidence to support the suggestion that sickle cell trait – a milder version of the disease
    – might also increase the risk.

It is thought that excessive alcohol intake may also increase
the risk of ischemic stroke by bringing about a rise in blood pressure. However, although drinking too much
alcohol is known to inflate the risk, people who consume moderate amounts (less
than 3 units per day) actually have a lower risk than those who do not drink at
all. This may be because moderate alcohol intake can improve blood lipid
levels, and so protect against vascular diseases such as stroke.

Non-modifiable risk factors for Ischemic stroke

Risk factors for stroke that cannot be modified include the

  • Male gender
  • Older age
  • Family
  • Past heart attack or stroke
  • Ethnicity.

It has also been suggested that migraine may increase the
risk of an ischemic stroke, particularly in women under the age of 35. Migraine
with aura (in other words, migraine accompanied by additional symptoms such as
visual disturbance and numbness or tingling) is associated with reduced blood flow to the brain and inflammation.

Transient ischemic attack, or TIA,
is often referred to as a ‘mini-stroke’. Like a stroke, it is a disturbance in
the function of the nervous system that is caused by a problem with the blood supply to the brain. However, unlike stroke,
the symptoms of TIA settle down within 24

People who have had a TIA
are known to have a higher risk of a stroke in the future. The chance of
someone who’s had a TIA having a stroke
within 3 months has been estimated to be between 15 and 20 per cent.

Recently identified risk markers

Additional markers (indicators) associated with an increased
risk of ischemic stroke include elevated levels in the blood of:

  • Homocysteine
    (a marker that is associated with early-onset atherosclerosis)
  • Lipoprotein(a)
    (a type of lipid in the bloodstream that
    is similar to LDL-cholesterol)
  • High-sensitivity
    C-reactive protein (CRP; a protein in the blood that suggests inflammation)
  • High blood levels of fibrinogen
    (a protein that helps the blood to clot)
  • Apolipoprotein
    B (APOB; the protein part of low-density lipoprotein

2.4 Risk factors for
Hemorrhagic stroke

Some of the risk factors for a hemorrhagic stroke – a stroke caused by a bleed – differ from
those of an ischemic stroke and so are looked at separately

Modifiable risk factors
for Hemorrhagic stroke

Those risk factors for hemorrhagic stroke that we can improve
upon include:

  • High blood pressure – one of the most important
    modifiable risk factors for stroke
  • Impaired
    ability of the blood to clot due to
    medication (‘anti-clotting’ drugs, anticoagulants; or ‘clot-busting’
    drugs, thrombolytic)
  • Smoking,
    excess alcohol intake and substance misuse (for example, amphetamines and cocaine)
  • Lipid
    levels. Unlike ischemic strokes, it seems that reducing cholesterol levels actually increases the risk
    of hemorrhagic strokes
  • Vascular
    malformations. These may include arteriovenous malformations, cavernous
    haemangiomas and aneurysms (an aneurysm
    is an abnormal dilation, or bulge, in the wall of an artery.) Vascular malformations are prone to
    rupture. Fortunately, they can sometimes be treated with surgery to reduce
    the risk.
  • Conditions
    that interfere with blood clotting, for example,
    blood dyscrasia (an abnormality in the
    balance of the different components of the blood).
    Treatment may lower the risk.

Non-modifiable risk
factors for Hemorrhagic stroke

The risk factors for hemorrhagic stroke that cannot be
modified include the following:

  • Increasing
    age. This may be partly because older age is associated with small blood vessel disease, which can increase the
    risk of blood vessel rupture. Increasing
    age also increases the likelihood of the condition amyloid angiopathy,
    which leads to protein build-up in the arteries of the brain, increasing
    the risk of bleeding.
  • Ethnicity.

Symptoms similar to a stroke can also sometimes arise as a
result of damage to blood vessels in the
brain following a head injury.

Other risk factors that can lead to a stroke

factors such as oral contraceptive use

replacement therapy or

 Pregnancy and childbirth in women with
pre-existing medical conditions may increase the risk of stroke in specific

medical conditions such as amyloid angiopathy and antiphospholipid antibody

of illicit drugs such as cocaine or LSD.

medications, such as tamoxifen, phenylpropanolamine, and thrombolytic.

In general, the risk factors for having an ischaemic stroke – a stroke that is caused by a blockage in
an artery supplying the brain – may be
divided into those that can be modified (improved upon), and those that cannot,
as discussed below. Although some risk factors cannot be changed – for example,
a person’s gender or age – it is still important to be aware of them. This is
because people who have a number of unmodifiable risk factors may benefit from
making a greater effort to improve those risk factors that can be modified.In
addition to these risk factors, which are often classed as ‘traditional’, we
are also starting to learn about more recently identified risk factors. Some of
the risk factors for a hemorrhagic stroke – a
stroke caused by a bleed – differ from those of an ischemic stroke and so are
looked at separately.

Self Assessment Chart of Stroke Risk

This is just a guide, but it demonstrates measures that can
take to decrease your risk of stroke.

Risk Factors







never smoked

quit after
smoking for less than 5 years

current smoker
less than 20/day

current smoker
more than 20/day



1 hour strenuous
activity at least 3 times per week

very active once
or twice a week

active once or twice a week

very little
physical activity



none known


family history



Blood Pressure


mild high blood

high blood pressure

severe high
blood pressure



0 – 44

45 – 64

65 – 74

75 +


Alcohol (male)

0-4 standard

up to 4

more than 4
drinks a day 2 or more days a week

more than 6
drinks, 4 or more days a week


Alcohol (female)

0-2 standard
drinks a week

up to 2 drinks a

more than two
drinks a day, 2 or more days a week

more than 4
drinks, 4 or more days a week



about average
for height





Family History

no strokes known

a relative has
had a stroke

a relative has
had a stroke while younger than 65

relatives have suffered from stroke



below average



severely raised


– 3

Mechanisms of Stroke

Biophysical Mechanisms of Stroke

Although the consequences of both
ischemic and hemorrhagic stroke are similar in that a vessel obstruction and
the resultant reduced blood flow to the brain may lead to neurological deficits
and possibly death, the biophysical and hemodynamic mechanisms behind the
obstruction of blood flow are different. Biophysical mechanisms for the
development of obstructions that ultimately lead to stroke can arise by six
distinct processes: atherosclerosis, embolus, thrombus, reduced systemic
pressure, hemorrhage, and vasospasm.


Atherosclerosis, commonly referred to as “hardening of the
arteries,” is a pathological process in which calcified lipid or fatty deposits
from the flowing blood accumulate circumferentially along the innermost intimal
layer of the vessel wall (Fig 1?). Atherosclerotic plaques are found almost
exclusively at the outer wall (hip) of one or both daughter vessels at major
bifurcations, including the carotid. Atherosclerosis and the development of
arterial plaques are the product of a host of independent biochemical processes
including the oxidation of low-density lipoproteins, formation of fatty
streaks, and the proliferation of smooth muscle cells. As the plaques form, the
walls become thick, fibrotic, and calcified, and the lumen narrows, reducing
the flow of blood to the tissues the artery supplies.

Schematic diagram of the distribution of
atherosclerotic plaque along the inner wall of the carotid artery bifurcation.

Atherosclerotic deposits promote the development of blood
clots or the process of thrombosis due in part to flow obstruction and to high
shear stresses exerted on the vessel wall by the blood. High wall shear stress
might mechanically damage the inner wall of the artery, initiating a lesion. On
the other hand, low wall shear stress might encourage the deposition of
particles on the artery wall, promoting the accumulation of plaque. Turbulence
has also been implicated in atherosclerotic disease both because it can
increase the kinetic energy deposited in the vessel walls and because it can
lead to areas of stasis, or stagnant blood flow, that promote clotting. In
addition, the presence of atherosclerotic lesions introduces an irregular
vessel surface that, as a result of turbulent blood flow, can cause the
dislodgment of plaques of varying size into the bloodstream until the plaque
lodges into a vessel of smaller size, preventing further passage of blood flow.
Atherosclerotic thrombosis accounts for 33% of all stroke cases.


An embolus represents gaseous or particulate (eg, atheromata)
matter that acts as traveling “clots.” A common example of emboli is a platelet
aggregate dislodged from an atherosclerotic lesion. The dislodged platelet
aggregate is transported by the bloodstream through the cerebrovasculature
until it reaches vessels too small for further propagation. The clot has
nowhere to go and remains there, clogging the vessel and preventing blood flow
from entering the distal vasculature. Although our discussion at the present is
focused primarily on the carotid arteries and associated cerebrovasculature,
emboli can originate from distant sources such as the heart, lungs, and
peripheral circulation, which could eventually travel within the cerebral blood
vessels, obstructing flow and causing stroke. Other sources of emboli include
atrial fibrillation and valvular disease. The severity of stroke depends on the
size of the embolus and the location of the obstruction. The bigger the embolus
and the larger the vessel obstruction, the larger the territory of brain at
risk. Approximately 31% of all stroke cases are attributed to emboli.


Thrombosis is an internal physiological mechanism responsible
for the clotting of blood. A thrombus is a blood clot, an aggregation of
platelets and fibrin formed in response either to an atherosclerotic lesion or
to vessel injury. In response to vessel or tissue injury, the blood coagulation
system is activated, which initiates the following cascade of processes
transforming prothrombin and resulting in a fibrin clot:  

????Fibrin Clot

Although a host of mechanisms and causes are responsible for
vessel injury, vessel injury can occur as a result of forces (shear stresses)7 coupled with the excess energy created
by the turbulent flow
8910 exerted against the inner (intimal)
lining of the vessel wall, particularly an atherosclerotic vessel wall.
Approximately 33% of all stroke cases are attributed to thrombi.

Reduced Systemic Pressure

The previously described mechanisms of blood flow obstruction
leading to stroke occur along localized regions of the cerebral arteries. It is
assumed in this instance that the heart is functioning normally under proper
systemic pressure. Cardiovascular diseases such as atrial fibrillation and
myocardial infarction weaken the cardiac wall and introduce abnormalities in
the physiological function of the heartbeat, which ultimately result in reduced
systemic pressure and conditions of ischemia.


Blood vessels are typically structurally adept to withstand
the dynamic quantities required to maintain circulatory function. For reasons
that are not entirely understood, the vessel wall can become fatigued and
abnormally weak and possibly rupture. With vessel rupture, hemorrhage occurs
with blood seeping into the surrounding brain tissue. As the blood accumulates
within the brain, the displaced volume causes the blood, now thrombosed, to
ultimately compress the surrounding vessels. The compression of vessels
translates into a reduced vessel diameter and a corresponding reduction in flow
to surrounding tissue, thereby enlarging the insult. Among the vascular lesions
that can lead to hemorrhagic strokes are aneurysms and arteriovenous malformations

Brain Aneurysms

is a form of cerebrovascular disease that manifests itself as a pouching or
ballooning of the vessel wall. The vascular dilatation develops at a diseased
site along the arterial wall into a distended sac of stressed and thinned
arterial tissue. The fully developed cerebral aneurysm typically ranges in size
from a few millimeters to 15 mm but can attain sizes greater than 2.5 cm. If
left untreated; the aneurysm may continue to expand until it ruptures, causing
hemorrhage, severe neurological complications and deficits, and possibly death.
In the United States, approximately 28 000 aneurysms rupture each year;
approximately 50% of these patients die or become permanently disabled as a
result of the initial hemorrhage, and another 25% to 35% die of a future

Blood flow in most aneurysms is regular and predictable
primarily according to the geometric relationship between the aneurysm and its
parent artery. As blood flows within the parent artery with an aneurysm,
divergence of blood flow, as occurs at the inlet of the aneurysm, leads to
dynamic disturbances with a Bernoulli Effect, producing increased lateral
pressure and retrograde vortices that are easily converted to turbulence.13 Blood flow proceeds from the parent
vessel into the aneurysm at the distal or downstream extent of the aneurysm
neck, circulates around the periphery along the aneurysm wall from the neck to
the top of the fundus (downstream to upstream), returning in a type of
“isotropic shower” along the aneurysm wall toward the neck region, and exits
the proximal or closest extent of the aneurysm neck into the parent vessel.

As flow persists, areas of stagnation or vortices develop
within a central zone of the aneurysm. These rotating vortices, formed at the
entrance to the aneurysm at each systole and then circulated around the
aneurysm, are caused by the slipstreams or regions of recirculating flow
rolling upon themselves when they enter the aneurysm at its downstream wall
during systole. The stagnant vortex zone occurs in the center and at the fundus
or upper portion of the aneurysm and becomes more pronounced in larger
aneurysms. It is this stagnant zone that is believed to promote the formation of
thrombi or blood clots, particularly in giant aneurysms.

Brain Arteriovenous Malformations

The normal human circulation originates from the heart and
consists of a branching arrangement of arteries of continually decreasing size
until they feed into a capillary bed before exiting the bed through small veins
that increase in size before returning to the heart. The capillary bed serves
an important purpose in that its vascular resistance slows the flow of blood
considerably to allow perfusion of oxygen and nutrients to surrounding tissue
and removal of cellular waste. In one form of cerebrovascular disease, AVMs,
the vessels constituting the capillary bed of the brain become malformed during
embryonic development and prohibit the opportunity for blood to properly
perfuse into the surrounding tissue.

are congenital vascular lesions that occur as a result of capillary
maldevelopment between the arterial and venous systems. Approximately 0.14% of
the United States population has an intracranial AVM that poses a significant
risk and represents a major life threat, particularly to persons under the age
of 50 years. The vessels constituting the AVM are weak and enlarged and serve
as direct shunts for blood flow between the high-pressure arterial system and
the low-pressure venous system, corresponding to a large pressure gradient and
small vascular resistance. The abnormal low-resistance, high-flow shunting of
blood within the brain AVM without an intervening capillary bed causes the
fragile dilated vessels in the nidus to become structurally abnormal and
fatigued, to further enlarge, and possibly to rupture.

A, MR angiogram of a human arteriovenous
malformation. B, Schematic diagram of a brain arteriovenous malformation,
depicting the structural and angioarchitectural components.

The abnormal microvessels of an AVM serve as passive conduits
for blood flow from the arterial circulation directly to the venous
circulation, bypassing their normal physiological function of brain tissue
perfusion. The hemodynamic consequences of an AVM occur as a result of two
interdependent circulatory mechanisms involved in the shunting of blood between
artery and vein.

In the normal cerebral circulation, blood flows under a high
cerebrovascular resistance and high cerebral perfusion pressure. However, the
presence of a brain AVM in the normal circulation introduces a second abnormal
circuit of cerebral blood flow where the blood flow is continuously shunted
under a high perfusion pressure through the AVM, possessing a low
cerebrovascular resistance and low venous pressure. The clinical consequence of
the abnormal shunt is a significant increase in blood returning to the heart
(?4 to 5 times the original amount, depending on the diameter and size of the
shunt), resulting in a dangerous overload of the heart and possible cardiac
failure. Volumetric blood flow through an AVM ranges from 200 mL/min to 800
mL/min and increases according to nidus size.

The abnormal shunting of blood flow by brain AVMs rapidly
removes or “steals” blood from the normal cerebral circulation and
substantially reduces the volume of blood reaching the surrounding normal brain
tissue. This phenomenon, known as cerebrovascular steal, depends on the size of
the AVM and is the most plausible explanation for the development of
progressive neurological deficits. Cerebrovascular steal could translate into
additional neurological complications developed as a result of cerebral
ischemia or stroke in neuronal territories adjacent to an AVM.

When bleeding
occurs in the subarachnoid space, the arteries in the subarachnoid space can
become spastic with a muscular contraction, known as cerebral vasospasm. The
contraction from vasospasm can produce a focal constriction of sufficient
severity to cause total occlusion. The length of time that the vessel is
contracted during vasospasm varies from hours to days. However, regardless of
the duration of vessel constriction during vasospasm, reduction of blood flow
induces cerebral ischemia, thought to be reversible within the first 6 hours
and irreversible thereafter. It has been shown that vasospasm is maximal
between 5 and 10 days after subarachnoid hemorrhage and can occur up to 2 weeks
after subarachnoid hemorrhage. The resultant damage to brain tissue can be
minimized with the administration of pharmacological agents such as the
vasodilator papaverine.

3.1.2 Inflammatory Mechanisms of Stroke

Basic and clinical research provides evidence that
inflammatory mechanisms play a central role in the pathogenesis and progression
of atherosclerosis, plaque rupture, thrombosis, and stroke. Inflammatory
biomarkers such as high-sensitivity C-reactive protein have been identified as
predictors of first stroke and prognosis after stroke. The value of
high-sensitivity C-reactive protein and other markers may depend on the
characteristics of the study population; their utility may be less among
populations with high vascular risk. A recent randomized, clinical trial
suggests that the use of rosuvastatin therapy in otherwise healthy patients
with high-sensitivity C-reactive protein >2 mg/dL can reduce the risk of a
first stroke by 50%. The prognostic role of high-sensitivity C-reactive protein
among patients after stroke, however, is less clear, and other biomarkers,
including lipoprotein-associated phospholipase A2, may provide
complementary information about the risk of stroke recurrence. Infections,
moreover, may contribute to inflammation and stroke risk. Although no single
infectious organism is likely to be identified as the direct cause of
atherosclerosis, summary measures of multiple chronic infectious exposures, or
“infectious burden,” have been associated with the risk of stroke and
atherosclerosis affecting the carotid arteries. Acute infections have also been
found to serve as stroke triggers in epidemiologic studies. Recommendations to
vaccinate patients with cardiovascular disease against influenza represent the
first specific anti-infective strategy to be used in vascular prophylaxis.
Further studies are needed to determine the role of treatment of inflammation
and infection in stroke prevention.

3.1.3 Mechanisms of cardio
embolic stroke

Cardiac embolism is often
involved as a mechanism for embolic stroke, and may be implicated in many
strokes that have traditionally been considered of unknown origin (cryptogenic
strokes). In recent years, significant advancements have been made in understanding
and reducing the risk of stroke from long-known cardio embolic sources (atrial
fibrillation, intracardiac thrombus or tumor, infective endocarditic). Also,
improved cardiac imaging, especially transesophageal echocardiography, has
allowed the identification of newer embolic sources of stroke (aortic
atheromas, patent foramen ovale, atrial septal aneurysm). This article reviews
the current understanding of cardiac embolism as a mechanism for stroke, and
the preventive options that are currently adopted to decrease the stroke risk.

3.1.4 Mechanism of stroke complicating
cardiopulmonary bypass surgery

Stroke is a devastating complication of cardiopulmonary
bypass (CPB) surgery which occurs in 1 to 5% of cases. Strategies to reduce its
incidence require knowledge of the underlying pathology and etiology. To
determine the incidence, pathology and etiology of stroke complicating CPB.
Prospective review of clinical, operative and cranial CT scan findings in all
cases of stroke complicating CPB procedures in our institution over an 18 month
period. Twenty-one (1.6%, 95% CI 0.9-2.3%) cases of stroke were identified from
1336 CPB procedures. Cranial CT scan, performed in all but one patient, was
normal in three patients or consistent with ischemic stroke in 17 patients.
There were no cases of hemorrhagic infarction or intracerebral haemorrhage. It
was difficult to differentiate embolic and borderzone infarcts in two cases.
After considering the clinical, operative and CT scan features together, 12
(57%, 95% CI 36-78%) of the cases were felt to be embolic in origin and nine
(43%, 95% CI 22-64%) due to hypoperfusion in a borderzone. This study
demonstrates that stroke remains an important complication of CPB procedures
with an incidence in our series of 1.6%. The pathologic type of stroke is
predominantly ischaemic in nature due to either cerebral embolism or borderzone
infarction. Strategies for stroke prevention in patients undergoing CPB should
be targeted primarily at these two mechanisms.

3.2 Prevention of Stroke

Strokes are usually the result of a combination of factors
that have been present or developing for a long period of time. If someone has
two or more of the risk factors below, stroke risk is dramatically increased.
Anyone who is high risk should see their doctor who will usually assess each
risk factor for stroke (and heart disease) before deciding on necessary

Here are some
simple rules to reduce stroke risk:

Get blood
pressure checked

Because it is one of the greatest stroke risk factors,
failure to detect and control high blood pressure is the number one cause of
avoidable strokes. A person with high blood pressure is up to seven times more
likely to have a stroke than someone with normal or low blood pressure. High
blood pressure puts too much pressure and stress on the walls of blood vessels
and increases the risk of both hemorrhages’ and blood clots.

Stop smoking

Smoking quadruples stroke risk. Chemicals and gases in
tobacco smoke speed up the process of atherosclerosis (hardening of the
arteries) and make blood vessels throughout the body tighten, reducing blood
flow. Smoking also makes the blood more likely to clot, especially inside
damaged blood vessels.

Note: If one smoke and have high blood pressure you are 18
times more likely to have a stroke than someone the same age that doesn’t smoke
and has normal blood pressure.

People who are physically inactive have greater stroke risk
than those who keep active. Being physically inactive over a long period is
linked to high blood pressure, a leading cause of strokes.

Studies now show that drinking up to two small alcoholic
drinks a day can reduce stroke risk – but drinking any more than that increases
stroke risk by as much as three times. A drinking binge creates as much as five
times greater risk. Regular heavy drinking increases stroke risk because it can
raise blood pressure and increase the risk of hemorrhage in the brain.

Eat a healthy
diet and reduce salt intake

Cutting down on fat and salt should lower a person’s blood
pressure and cholesterol levels. Too much fat in a diet can cause silting of
the arteries (atherosclerosis), which can cause strokes. Too much salt can
raise blood pressure and this also can cause strokes.


Cholesterol is essential to the body’s cells and normally the
body will produce all the cholesterol it requires. Consuming foods high in
cholesterol and saturated fats may accelerate atherosclerosis. Keep on top of
cholesterol levels by having a blood test and by being prepared to change your
eating habits. If necessary, a doctor might also prescribe a cholesterol
lowering drug (called lipid-lowering agents, usually a ‘statin’).

Find out atrial

Atrial fibrillation is a type of irregular heartbeat. People
with this condition have a five times greater stroke risk because the irregular
heartbeat may lead to blood clots forming in the heart. These can then break
off and travel though the blood vessels to the brain where they may cut off
blood supply, causing a stroke.

If someone suspects they have atrial fibrillation, it is
important to see a doctor. The doctor might prescribe tablets to make the blood
less sticky and less likely to form clots (warfarin) and make the heartbeat
more regular.

Being overweight strains the entire circulatory system and creates
higher cholesterol levels, high blood pressure and diabetes – all of which
increase stroke risk.

The goals of stroke treatment

restore blood flow to the brain (in those people with an
ischemic stroke) or stop the bleeding (in those
people with hemorrhagic stroke) .

monitor vital signs to detect and treat stroke complications .

lifelong changes to reduce the chances of another stroke.

Depending on the
situation and the type of stroke treatment options for a stroke may include :

such as thrombolytic (“clot-busting”) drugs


Stroke rehabilitation and lifestyle changes.

people who have had an ischemic stroke, it may involve the use of thrombolytic
(“clot-busting”) drugs to dissolve blood clots that are blocking
blood flow to the brain. Other medicine that doctors may use to treat a stroke
may include anticoagulants and antiplatelets. After a stroke survivor has left
the hospital, treatment often continues in the form of rehabilitation.
Lifestyle changes are often part of long-term treatment following a stroke.
Risk factor modification, medications and, in some cases, surgery can help to
minimize the risk of having a stroke.

Treatment of Stroke

Regular medical supervision, medication
and lifestyle changes

Medical advice
will be given on continuing care for stroke survivors and may include:

medical supervision

of blood pressure
and cholesterol levels leading to appropriate medication.

-one in
ten stroke patients have a very narrow artery in the front of the neck on one
side (the carotid artery) that restricts the flow of blood to the brain.
Surgery to open and clear the artery or to place a small cylinder (stent) in it
will increase the flow.

Medication – two kinds of tablets are
prescribed: “clot-busters” and blood-thinners .

v  Anti-clotting (antiplatelet)
medication, such as aspirin, probably in combination with another drug such as
clopidogrel or dipyridamole (for those patients who have had an ischaemic
stroke caused by a clot forming on an area of hardening of the arteries).

v  Anti-coagulant medication (such
as warfarin) where an ischaemic stroke has been caused by a blood clot forming
in the heart, breaking off and lodging in the brain. These drugs are very
powerful, may have significant side effects and must be carefully supervised by
the doctor.

Changes to lifestyle

v  Attention to diet, which should
be varied, but low in saturated fat, alcohol, and salt, and high in fiber,
fruit and vegetables.

v  Avoidance of smoking – this is
absolutely essential.

v  Stress management – stress in
life is unavoidable but can be reduced by various strategies including
exercise, changing attitudes to work, meditation and relaxation.

v  Regular exercise – which will
help to regulate weight and improve circulation.

There are various techniques that can be used to try to help
or compensate for the various visual effects of stroke. These include glasses,
prisms, patching, magnifiers and scanning information to name a few.

The focus in working with stroke sufferers is on
rehabilitation and that also applies with vision related problems. Orthoptists
and Low Vision Specialists can assess and work with people with visual training
with or without optical aids; the stroke team, GP or Ophthalmologist can refer
people for an orthoptic assessment and / or to the Low Vision Clinic.

Some people may see some improvement in their vision up to
four months following a stroke. Again, this is highly dependent on where the
damage in the brain occurred as well as the type of stroke suffered and other
existing health problems. Unfortunately for many people, especially those with
loss of visual field, sight loss may be permanent.

3.5 Recovery from Stroke

Recovery from stroke
takes time. Recovery from stroke can be remarkable and inexplicable.

  • A
    rehabilitation unit in the hospital
  • A
    rehabilitation hospital
  • Home
  • Home with
    outpatient therapy
  • A long-term
    care facility that provides therapy and skilled nursing care.
  • Resuming work
  • Driving
  • Sexual activity
  • Sport and Exercise
  • Drinking Alcohol

The intake of
excessive amounts of alcohol should be avoided after stroke as it may interact
adversely with medication, raise blood pressure, and affect judgement resulting
in injury. Moderate consumption (two standard drinks per day) should not cause
any problem.

Other vision problems associated with stroke
A common effect of stroke-related vision
problems is an increased sensitivity to light. The brain seems to have
difficulty adjusting to different levels of light. Tinted glasses or sunglasses
may be helpful in reducing the discomfort some people experience.  Another problem which can follow stroke is
dry eye. The rate of blinking may slow following a stroke and /or there may be
incomplete eye closure with a partial blink which will cause a part of the
cornea to dry resulting in the eye feeling uncomfortable. Artificial tears, and
reminding the person to try to blink completely and often, may be a possible
solution for dry eyes.

Recovery and Rehabilitation

Much is still not known about how the brain compensates for
the damage caused by stroke. Some brain cells may be only temporarily damaged,
not killed, and may resume functioning. In some cases, the brain can reorganize
its own functioning: another part of the brain ‘takes over’ for a damaged part.
Stroke survivors sometimes experience remarkable and unanticipated recoveries
that can’t be explained. Recovery after stroke takes time. It is greatest in
the first few months, and gradually plateaus, although small gains may be made
for the next 1 to 2 years. The rate of recovery will vary greatly amongst
patients. Rehabilitation starts in the hospital as soon as possible after the
stroke. In patients who are stable, rehabilitation may begin two days after the
stroke has occurred, and should be continued as necessary after release from
the hospital.  Before discharge a conference with hospital staff regarding
future care, supervision and rehabilitation is essential.

Depending on the severity of the effects of the stroke,
rehabilitation options include:

3.6 Life after Stroke

Patients are generally encouraged to
return to their normal lives – depending on the effects persisting from stroke.

Some aspects of life after stroke include:

soon this is possible depends partly on remaining disability, the type of work
involved, and the feelings about returning to work. Some people feel quite
tired after a stroke, and have difficulty carrying out any kind of physical
activity for any length of time. Part-time work at least in the early stages
may be a good idea. Unless the stroke has reduced awareness of impairment, it
is probable that the person who had the stroke is the best judge of when to
return to work. 

someone who appears to have made a full recovery after stroke should not drive
a car for at least a month as the risk of another stroke is greatest at this
time. To drive again involves being cleared by the doctor (who will be aware of
relevant government regulations) as the stroke may have left subtle
impairments, not always apparent, such as poor co-ordination, lack of awareness
on one side, difficulties in judging distance, changes in vision, difficulties
in concentration and confusion between left and right.

of sexual activity after stroke is encouraged. Most couples experience some
difficulty in their sex life after stroke, but this is usually due to
psychological factors rather than any disability caused by stroke.  A
doctor can advise on any difficulty such as erectile problems in men.

of physical activity and hobbies is an important part of rehabilitation- normal
activity should be resumed as soon as physically possible.

Chapter – 4

4.1 Literature Review

A Stroke is a ‘Brain attack’ that
occurs when blood flow to the brain is interrupted and oxygen does not get to
an area of the brain . When this happens, brain cells begin to die and brain
damage occurs. There are two types of stroke, hemorrhagic and ischemic.
Ischemic strokes can be further broken down into two types-embolic and thrombotic.
Of all strokes, 87% are ischemic. Embolic strokes are caused by a traveling
atherosclerotic clot. Atherosclerosis is a condition in which fatty material is
deposited along the walls of arteries. This fatty material thickens, hardens
and may eventually block the arteries. Thrombotic strokes are caused by
blockages in the arteries providing blood flow to the brain. About 700,000
Americans each year suffer a new or recurrent stroke. That means, on average, a
stroke occurs every 45 seconds. Stroke kills more than 150,000 people a year.
That’s about 1 of every 16 deaths. It’s the No.3 cause of death behind diseases
of the heart and cancer. On average, every 3 to 4 minutes someone dies of stroke.
Of every 5 deaths from stroke,2 occur in men and 3 in women.

Stroke is a leading cause of
serious, long term disability in the United States. The 2004 stroke death rates
per 100,000 population for specific groups were 48.1 for white males, 47.4 for
white females,73.9 for black males and 64.9 for black females. About 15% of all
strokes are heralded by Transient Ischemic Attacks (TIA).In person’s ages 45-64
years old, 8-12% of ischemic strokes result in death in 30 days.

Stroke is a major cause of
mortality in the UK, accounting for around 53,000 deaths every year. In those
aged under 75, around one in twenty deaths are from stroke, making it a major
cause of premature mortality. Stroke mortality rates for men and women are now
at about a third of the level they were in 1968. There is a north-south
gradient in stroke mortality with rates in Scotland around 50% higher than in
London. Social inequalities in stroke are persistent and premature death rates
in the most deprived areas are around three times higher than in the least
deprived. The stroke mortality rate for men born in Bangladesh is three times
higher than those born in England and Wales and this gap has increased since
the early 1980s. Using the most recent measures of stroke incidence rates, we
estimate that there are around 111,000 first strokes in the UK every year. The
prevalence of stroke among those aged over 75 is increasing in England. For
men, the prevalence in this age group has increased from 9% in 1994 to 13% in
2006. There are over 21,000 surgical procedures related to stroke every year in
England, with a similar number performed on men and women. Nearly 40% men and
more than 30%women in England have high blood pressure, a key risk factor for
stroke. Half of people with high blood pressure are not receiving treatment.
The prevalence of obesity in England in 2006 was around 50% higher than in
1994. Stroke is a major health issue for women, particularly for women. The
length of time to recover from a stroke depends on its severity. Carotid artery
blockages are the major contributor to the most common type of stroke.

Effects of a left-sided stroke
include paralysis, speech/ language problems, a slow, cautious behavioral style
and memory loss. The effects of stroke on the right hand side of the body will
include paralysis, vision problems, a quick, inquisitive behavioral style and
memory loss. Stroke risk factors that can not be changed include being over age
55, family history of stroke, being of African-American race and male gender.
Factors that can be modified include high blood pressure, high cholesterol,
smoking, diabetes and atrial fibrillation (a heart rhythm disorder).

Stroke is an important medical issue in a woman’s life. In
general, a stroke is seen as a medical problem more common among men. In
reality, stroke accounts for a higher proportion of death among women than men.
A stroke can strike at any age, and despite the fact that it is perceived as an
elderly problem, more than 30 percent of all strokes occur in women under the
age of 65. A new study published in 2007 found that more women than men appear
to have middle age strokes. The risk of stroke is higher in this age group
(35-64) because women tend to have more complications from obesity than men,
and experience higher blood pressure and high cholesterol problems. Statistics
show that in developing countries, half of all deaths in women over the age of
50 are due to heart diseases and stroke.

According to
the American Stroke Association, stroke is the third leading cause of death
among American women. In the United States, one in 2.5 women die of heart
disease, stroke or other cardiovascular disorders, compared with one in 30 who
dies of breast cancer. Studies also show that women who survived a stroke have
a higher risk than men to undergo a poor recovery. Today, more than 2 million
American women live with the consequences of a stroke. Unfortunately, only 13
percent of the adult women know that heart problems and stroke are the greatest
threats to their health.

the symptoms of a stroke is essential for receiving treatment, reducing the
risk of disability and death. Unfortunately, women are more likely to delay
receiving treatment than men. Studies also show that women take up to 46
percent longer to get to the hospital than men after the first stroke symptoms
occur. One of the reason for delaying treatment is that only a reduced number
of women can properly recognize stroke symptoms.

The common stroke symptoms include:

(1) Sudden
numbness, weakness, clumsiness, or paralysis on one side of the body.

(2) Sudden
confusion, slurred speech, trouble speaking, or understanding speech.

(3) Sudden
blurred vision or loss of sight in one or both eyes.

(4) Sudden
trouble walking, dizziness, loss of balance or coordination.

(5) Sudden
severe headache with no known cause.

(6) Loss of
balance or unsteadiness.

However, the
new research has discovered that women are less likely to experience the
traditional stroke symptoms. This can be one of the reasons why women delay

Some of the
additional symptoms experienced by women include:

(1) Loss of
consciousness or fainting.

(2) Shortness
of breathing.

(3) Sudden
face, chest and limb pain.

(4) Sudden hiccups

(5) Sudden nausea

(6) Seizure

(7) Sudden
tiredness or general weakness.

8) Sudden
pounding and racing heartbeat (or palpitations).

Women and men
share similar risk factors, but women also face gender related risk. Some of
the following risk factors are important for women under the age of 55.

The Healthy People 2010 target
for coronary heart disease is to reduce deaths to less than 166 per 100,000
people. In 2003, the death rate in Colorado was 118.6, surpassing the target by
28.5 percent. Although the target was reached, programmatic efforts to maintain
and further decrease the death rate for coronary heart disease will be
important in Colorado, as it remains our number one public health problem. The
Healthy People 2010 target for stroke is to reduce deaths to less than 48 per
100,000 people. In 2003, the death rate in Colorado was 51.3. By 2010, the
stroke death rate needs to decrease by 6.9 percent. A recommendation is to
focus programmatic efforts on health disparities since the biggest decrease
(28.7 percent) is needed among Blacks while an 8.7 percent decrease is
necessary for Whites to reach the 2010 target. Furthermore, a 7.5 percent
decrease is needed for females while a 3.8 percent decrease is needed for

Primary prevention is one major
strategy to reduce the development of cardiovascular disease and stroke,
specifically through lifestyle interventions that promote heart-healthy
behaviors. High cholesterol is one of the major risk factors that can be
modified. To prevent or lower cholesterol, lifestyle changes include eating a
diet low in saturated fat and cholesterol, increasing physical activity, and
reducing excess weight. The Healthy People 2010 target is to reduce the
proportion of adults with high cholesterol to 17 percent. This presents a major
challenge as 31.9 percent of Colorado adults had high cholesterol during 2003
and the data from 1995 to 2003 indicate an increasing trend. A decrease of 46.7
percent from the 2003 percentage needs to occur to reach the target. High blood
pressure is another major risk factor for heart disease and stroke. The Healthy
People 2010 target is to reduce the proportion of adults with high blood
pressure to 16 percent. In 2003, this percentage was 19.8 among Coloradans. A
19.2 percent decrease from the 2003 percentage is necessary to reach the

Chapter 5

Conclusion and

Recent advances in the treatment
of stroke are based on increasing knowledge of its underlying biophysical
mechanisms, as well as on better-publicized advances in imaging instrumentation
and procedures for the management and treatment of patients. Identification of
risk factors is the only way to achieve this goal. Implementation of screening
programme in community to identify risk factors and educate people about
primary prevention should be initiated in this regard. This way, we can reduce
morbidity and mortality among stroke patients and alleviate the burden of stroke.

Management of risk factors is critical to prevent stroke. Not only
pharmacological treatment, but also life-style modification including diet and
exercise are recommended. Evidence-based recommendations found in treatment
guidelines are useful, especially for hypertension, dyslipidemia, and atrial
fibrillation in which the clinical trial evidence is rich. Yet there are many
established and less-established risk factors lacking scientific evidence for
screening and treatment. Although science seeks independent contribution of
each risk factor to disease, management to one can bring additional improvement
of other factors in practice and the accumulation of each improvement will
finally decrease the stroke risk. Further investigations are much needed to
establish the best management of important and common risk factors.

Screening for conventional
cardiovascular risk factors remains the most important considering the high
percentage of cardiovascular risk factors in patients under age 50. These high
frequencies also indicate optimal secondary prevention strategies. Based on the
low laboratory yield of thrombophilia- and auto-immune search, it is not
indicated to do this complete laboratory search in all patients under 50,
especially not when there is no history related to these diseases. Furthermore
in most cases a positive thrombophilic factor has no therapeutic consequences,
such as switching of type of anticoagulation or duration of anticoagulation.
Thrombophilia and auto-immune research is only indicated in specific cases.
Because of the low number of abnormalities found in TTE, TEE seems preferable
instead. Disadvantage of the transesophageal technique is its more invasive

Another possibility
is the use of TEE in selected young patients, without other risk factors for
ischemic stroke. The ECG should be used to exclude atrial fibrillation. It is
cheap and simple. The use of duplex ultrasound of the extra cranial arteries
should be continued. It is a non-invasive test and gives information about the
presence of atherosclerosis or dissection in the carotid arteries. Is has a
sensitivity of 86% and specificity of 87% .History taking remains important in
detecting risk factors. Characteristics of auto-immune diseases could be specifically


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Figure : Different
types stroke

Stroke: Classification

Stroke: Etiology
Image of city scan