Stroke, sometimes called a “brain attack,” occurs when blood flow to an area in the brain is cut off. As a result, the brain cells, deprived of the oxygen and glucose needed to survive, die. If not caught early, permanent brain damage can result.

People who have high blood pressure are 4 to 6 times more likely to have a stroke. Over time, hypertension leads to atherosclerosis and hardening of the large arteries. This, in turn, leads to blockage and weakening of the walls of small blood vessels in the brain, causing them to balloon and burst. The risk of stroke is directly related to how high the blood pressure is.

There are two types of stroke.

• Ischemic stroke is similar to a heart attack, except it occurs in the blood vessels of the brain. Clots can form either in the brain’s blood vessels, in blood vessels leading to the brain, or even blood vessels elsewhere in the body which then travel to the brain. These clots block blood flow to the brain’s cells. Ischemic stroke can also occur when too much plaque (fatty deposits and cholesterol) clogs the brain’s blood vessels. About 80% of all strokes are ischemic stroke.
• Hemorrhagic (heh-more-raj-ik) strokes occur when a blood vessel in the brain breaks or ruptures. The result is blood seeping into the brain tissue, causing damage to brain cells. The most common causes of hemorrhagic stroke are high blood pressure and brain aneurysms. An aneurysm is a weakness or thinness in the blood vessel wall that causes it to balloon outward.

Signs of Stroke

If you experience any of the following signs you or a loved one are having a stroke, call 911 immediately.

Sudden numbness or weakness in the face, arm, or leg (especially on one side of the body)
Sudden blurred vision or decreased vision in one or both eyes
Sudden inability to move part of the body (paralysis)
Sudden dizziness or headache with nausea and vomiting
Difficulty speaking or understanding words or simple sentences
Difficulty swallowing
Dizziness, loss of balance, or poor coordination
Brief loss of consciousness
Sudden confusion

SOURCE: webmd.com
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