A Stroke, Sometimes Called A Cerebrovascular Accident (CVA), Results From Damage To Part Of The Brain Because Its Blood Supply Is Cut Off.
The blood supply to the brain can be undermined by a blockage (thrombosis or embolism) or a flow (haemorrhage) from one of the arteries in the brain. A CVA is more common in people who have high blood pressure, diabetes and high cholesterol levels. People who have an irregular heartbeat (atrial fibrillation) are also more susceptible to strokes. After a stroke, part of the brain no longer functions and pressing medical attention is needed.
There’s generally little or no warning of a stroke. Instant entry to hospital for evaluation and treatment is crucial if there’s to be a possibility of preventing irreversible brain damage. The after effects of a stroke vary determined by the place and extent of the damage. They vary from moderate, temporary symptoms, including loss of eyesight, to lifelong impairment or, in some individuals, if the stroke causes extensive brain damage, to coma and death.
If the symptoms disappear within a 24 hour interval, the state is called a transient ischaemic attack or TIA, which is a warning signal of a possible future stroke.
How Common Is It?
Each year about 100,000 people in the UK have a stroke and the risk increases with age.
A 70-year old living in the United Kingdom is about 100 times more likely to have a stroke than a 40- year old. Although the variety of deaths from stroke has fallen over the last 50 years, stroke continues to be the third most common cause of death after heart attacks and cancer in the United Kingdom.
What Are The Causes?
- About half of all strokes happen when a blood clot forms in an artery in the brain, a procedure called cerebral thrombosis.
- Cerebral embolism occurs when a fragment of a blood clot that has formed elsewhere in the body, for example in the heart or the principal arteries of the neck, goes in the blood and lodges in an artery supplying the brain. Just under one third of all strokes are due to cerebral embolism.
- Cerebral haemorrhage (bleeding), which causes about one fifth of all strokes, occurs when an artery supplying the brain ruptures and blood seeps out into the brain itself.
- Blood clots that bring about cerebral thrombosis and cerebral embolism are more likely to form in an artery which has been damaged by atherosclerosis, a condition in which oily’ deposits (atheroma) build up in artery’ walls. Variables that raise the risk of atherosclerosis are a high fat diet, smoking, diabetes mellitus and increased blood cholesterol levels.
What Are The Risks?
- The risk of cerebral embolism, thrombosis or haemorrhage is increased by high blood pressure, which ought to always be evaluated and treated quickly.
- Cerebral embolism may be a complication of some heart conditions for example heart rhythm disorders, heart valve disorders and a recent heart attack, all which can cause blood clots to form in the heart.
- Sickle-cell anaemia, an abnormality of the red blood cells, also raises the risk of cerebral thrombosis because strange blood cells often clump together and block blood vessels. .
- Less typically, thrombosis is brought on by narrowing of the arteries supplying the brain as a result of inflammation of an autoimmune disorder, including polyarteritis nodosa, where the immune system attacks the body’s own healthy tissues.
What Are The Symptoms?
Generally in most individuals, the symptoms develop quickly over a matter of seconds or minutes. The precise symptoms are determined by the region of the brain changed. The symptoms may contain:
- weakness or inability’ to move on one side of the body
- numbness on one side of the body
- tremor, clumsiness or loss of control of fine movements
- visual disturbances, for example loss of eyesight in one eye
- slurred speech
- trouble in locating words and comprehending what others are saying
- vomiting, vertigo and trouble in keeping equilibrium.
With a serious stroke, the affected individual may become unconscious and may decline into coma and die.
How is It Diagnosed?
- If you imagine that somebody has had a stroke, take them to the hospital promptly to discover the cause and begin treatment.
- Imaging of the brain, including computerized tomography (CT) scan or magnetic resonance imaging (MRI), may be done
- to learn whether the stroke was due to bleeding or a blockage in a vessel.
- Antihypertensive drugs, which help control
- raised blood pressure, and a daily dose of aspirin, which reduces the danger of blood clot formation, may be prescribed.
- Smokers should stop smoking immediately.
- Weakness and loss of motion may be treated with physiotherapy.
- Language difficulties can be eased with speech therapy.
- Antidepressant drugs or counselling may help treat the depression that can follow a stroke.
What is The Prognosis?
Treatment of risk factors, like high blood pressure, will lower the danger of a future, possibly deadly stroke. Clot-busting drugs may be given to dissolve a clot.
Cerebral angiography uses X rays to search for abnormalities of the arteries supplying the brain. It’s frequently used to inquire transient ischaemic attack and stroke. Under local anaesthesia, a thin, flexible tube called a catheter is inserted into an artery, usually at the groin or elbow, and directed to an artery in the neck. When the catheter is in place, a special dye that shows up on X rays is injected through it. The outline of the blood flow through the arteries is subsequently seen on the X-ray (angiogram).