Outline
Introduction🧁
Stroke is a disease that affects the arteries leading to and within the brain. It is the No. 5 cause of death and a leading cause of disability in the United States.
A stroke occurs when a blood vessel that carries oxygen and nutrients to the brain is either blocked by a clot or bursts (or ruptures). When that happens, part of the brain cannot get the blood (and oxygen) it needs, so brain cells die.
The brain is an extremely complex organ that controls various body functions. If a stroke occurs and blood flow can't reach the region that controls a particular body function, that part of the body won't work as it should.
The effects of a stroke depend on several factors, including the location of the obstruction and how much brain tissue is affected.
However, because one side of the brain controls the opposite side of the body, a stroke affecting one side will result in neurological complications on the side of the body it affects
Symptoms
Stroke symptoms may happen suddenly. Each person’s symptoms may vary
● Numbness or weakness of face, arm, or leg, especially on one side of the body
● Confusion, trouble speaking or understanding words
● Trouble seeing from one or both eyes
● Trouble walking, dizziness, loss of balance or coordination
● Severe headache with no known cause
**If you have the above symptoms, it’s advised to get help immediately
F.A.S.T. Warning signs
Use the letters in F.A.S.T to spot a Stroke
● F = Face Drooping – Does one side of the face droop or is it numb? Ask the person to smile.
● A = Arm Weakness – Is one arm weak or numb? Ask the person to raise both arms. Does one arm drift downward?
● S = Speech Difficulty – Is speech slurred?
● T = Time to go to the hospital
What are some types of stroke?
Every stroke is unique, but strokes tend to affect people in common ways. Stroke can be caused either by a clot obstructing the flow of blood to the brain (called an ischemic stroke) or by a blood vessel rupturing and preventing blood flow to the brain (called hemorrhagic stroke). A TIA (transient ischemic attack )or "mini stroke,” is caused by a temporary clot.
Ischemic Stroke Ischemic stroke occurs when a vessel supplying blood to the brain is obstructed. It accounts for about 87 % of all strokes. Fatty deposits lining the vessel walls, called atherosclerosis, are the main cause for ischemic stroke. Fatty deposits can cause two types of obstruction:
Cerebral thrombosis is a thrombus (blood clot) that grows at the fatty plaque within the blood vessel.
Cerebral embolism is a blood clot that forms at another location in the circulatory system, usually at the heart and large arteries of the upper chest and neck. Part of the blood clot breaks loose, enters the bloodstream and travels through the brain’s blood vessels until it reaches vessels too small to let it pass. A main cause of embolism is an irregular heartbeat called atrial fibrillation. It can cause clots to form in the heart, dislodge and travel to the brain.
Silent Stroke
You could have a stroke and not know it. Silent cerebral infarction (SCI), or silent stroke, is a brain injury likely caused by a blood clot that interrupts blood flow in the brain. It’s a risk factor for future strokes and a sign of progressive brain damage.
Hemorrhagic Stroke
Hemorrhagic strokes make up about 13 % of stroke cases. They're caused by a weakened vessel that ruptures and bleeds into the surrounding brain. The blood accumulates and compresses the surrounding brain tissue.
The two types of hemorrhagic strokes are intracerebral (within the brain) hemorrhage or subarachnoid hemorrhage.
Two types of weakened blood vessels usually cause hemorrhagic stroke: arteriovenous malformation (AVMs):
An arteriovenous malformation (AVM) is a cluster of abnormally formed blood vessels. Any one of these vessels can rupture, also causing bleeding into the brain.
Aneurysms:
An aneurysm is a ballooning of a weakened region of a blood vessel. If left untreated, the aneurysm continues to weaken until it ruptures and bleeds into the brain.
TIA
TIA is a temporary blockage of blood flow to the brain. Since it doesn’t cause permanent damage, it’s often ignored. But this is a big mistake. TIA may signal a full-blown stroke ahead.
They have the same symptoms as stroke, but the symptoms don’t last. If you have had one or more TIAs, you are almost 10 times more likely to have a stroke than someone of the same age and sex who has not had a TIA.
Cryptogenic Stroke (Stroke of Unknown Cause)
In most cases like we said before a stroke is caused by a blood clot that blocks blood flow to the brain. But in some instances, despite testing, the cause can’t be determined. Strokes without a known cause are called cryptogenic.
Because approximately 1 in 4 stroke survivors will likely have another stroke event, finding the cause of the stroke will help your physician treat the cause of your stroke and lower the likelihood of another. Having a cryptogenic stroke may be frustrating and overwhelming, but with a proper diagnostic workup and collaboration with your healthcare team, you can take part in finding the cause of your stroke and help prevent another one from occurring.
Brain Stem Stroke
Brain stem strokes can have complex symptoms, and they can be difficult to diagnose.
A person may have:
vertigo
severe imbalance without the hallmark of most strokes (usually occur together)
weakness on one side of the body. dizziness alone is not a sign of stroke.
A brain stem stroke can also cause
double vision
slurred speech
decreased consciousness.
Only a half-inch in diameter, the brain stem controls all basic activities of the Central Nervous System (CNS): consciousness, blood pressure and breathing. All motor control for the body flows through it. Brain stem strokes can impair any or all of these functions.
More severe brain stem strokes can cause locked-in syndrome, a condition in which survivors can move only their eyes.
If a stroke in the brain stem results from a clot, the faster blood flow can be restored, the better the chances for recovery. Patients should receive treatment as soon as possible for the best recovery.
Like all strokes, brain stem strokes produce a wide spectrum of deficits and recovery. Whether a survivor has minor or severe deficits depends on the location of the stroke within the brain stem, the extent of injury and how quickly treatment is provided.
Risk factors for brain stem stroke are the same as for strokes in other areas of the brain.
Recovery is possible. Since brain stem strokes do not usually affect language ability, the patient is often able to participate more fully in rehabilitation. Double vision and vertigo usually resolve after several weeks of recovery in mild to moderate brain stem strokes.
Risks of a Stroke
Anyone can have a stroke at any age. But your chance of having a stroke increases if you have certain risk factors. Some risk factors for stroke can be changed or managed, while others can’t.
Risk factors for stroke that can be changed, treated, or medically managed:
High blood pressure: Blood pressure of 140/90 or higher can damage blood vessels (arteries) that supply blood to the brain.
Heart disease: Heart disease is the second most important risk factor for stroke, and the major cause of death among survivors of stroke.
Diabetes: People with diabetes are at greater risk for a stroke than someone without diabetes.
Smoking: Smoking almost doubles your risk for an ischemic stroke
Lack of exercise
Obesity
Excessive alcohol use: More than 2 drinks per day raises your blood pressure. Binge drinking can lead to stroke.
Illegal drugs: IV (intravenous) drug abuse carries a high risk of stroke from blood clots (cerebral embolisms). Cocaine and other drugs have been closely linked to strokes, heart attacks, and many other cardiovascular problems.
Abnormal heart rhythm: Some types of heart disease can raise your risk for stroke. Having an irregular heartbeat (atrial fibrillation) is the most powerful and treatable heart risk factor of stroke.
Cardiac structural abnormalities: Damaged heart valves (valvular heart disease) can cause long-term (chronic) heart damage. Over time, this can raise your risk for stroke.
Risk factors for stroke that can’t be changed:
Older age: For each decade of life after age 55, your chance of having a stroke more than doubles.
Race: African Americans have a much higher risk for death and disability from a stroke than whites. This is partly because the African-American population has a greater incidence of high blood pressure.
Gender: Stroke occurs more often in men, but more women than men die from stroke.
History of prior stroke: You are at higher risk for having a second stroke after you have already had a stroke.
Heredity or genetics: The chance of stroke is greater in people with a family history of stroke.
Other risk factors include:
Where you live: This may be because of regional differences in lifestyle, race, smoking habits, and diet.
Temperature, season, and climate: Stroke deaths occur more often during extreme temperatures.
Social and economic factors:There is some evidence that strokes are more common among low-income people.
History of TIAs (Transient Ischemic Attacks)📖
High red blood cell count: A significant increase in the number of red blood cells thickens the blood and makes clots more likely. This raises the risk for stroke.
High blood cholesterol and lipids: High cholesterol levels can contribute to thickening or hardening of the arteries (atherosclerosis) caused by a buildup of plaque. Plaque is deposits of fatty substances, cholesterol, and calcium. Plaque buildup on the inside of the artery walls can decrease the amount of blood flow to the brain. A stroke occurs if the blood supply is cut off to the brain.
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