A stroke,
also called cerebrovascular accident (CVA) or brain attack., is the loss of
brain functions due to the deficiency of blood supply to the brain. This is
caused by:
- Lack of
blood flow (or ischemia) caused by the physical blockage of blood flow to an
area of the brain. The most common forms of ischemic stroke are:
- Embolic Stroke.
It is
caused by blockage of one of the arteries to the brain by a blood clot. This
clot is usually formed in the heart and travels to the brain as an embolus until
it reaches a narrow point where it becomes trapped.
- Thrombotic Stroke.
In this
type of stroke a blood clot forms along the inside of a blood vessel. This clot
is called thrombus and usually affects small blood vessels in the brain.
- Leakage of
blood (or hemorrhage). It occurs when a blood vessel inside of the brain
ruptures. As consequence, blood accumulates in or around healthy brain tissue.
Stroke
symptoms typically start suddenly, without warning, and depend on the area of
the brain affected.
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