What is Stroke?

Stroke is a sudden loss of muscle function, vision, or speech, caused by artery problems that injure the brain. It is very important to call 9-1-1 quickly for someone who has symptoms of stroke. Time lost is brain lost.

Stroke is a 'brain attack'

Stroke is often called a “brain attack” because it affects the arteries leading to and within the brain. A stroke happens when an artery that carries oxygen and nutrients to the brain is either blocked by a clot or bursts. When that happens, part of the brain cannot get the blood (and oxygen) it needs and starts to die.

Ischemic stroke, about 80 percent of all strokes, is caused by a severe blockage of blood to part of the brain. Most commonly, blood flow through an artery is blocked by atherosclerosis (narrowed arteries).

Hemorrhagic stroke occurs when arteries break, causing bleeding into or around the brain.

Some strokes can’t be prevented. Most strokes can be avoided by treating risk factors, such as high blood pressure, high blood cholesterol and diabetes. It is very important to get medical treatment quickly. The best way to do that is by calling 9-1-1.

Treatments can be given in an ambulance or shortly after arriving at a hospital that can stop a stroke by quickly dissolving a blood clot in an ischemic stroke, or stopping the bleeding of a hemorrhagic stroke.

Time is brain – there is a short period of time after the symptoms start, when serious damage can be prevented. Rehabilitation after a stroke helps people overcome disabilities that result from damage to the brain.

For more information:

• Medline Plus – stroke

• American Stroke Association – Learn about stroke

• National Stroke Association – What is stroke?

• Food and Drug Administration – Brain Attack