Stroke Overview

A stroke (cerebrovascular disease or "brain attack") occurs when a blood vessel in the brain becomes blocked or ruptures. Without oxygen and nutrients, the brain cells in that part of the brain start to die, which can result in permanent damage to the brain.

There are two main and one minor type of stroke:

Ischemic stroke

An ischemic stroke is the most common type of stroke, accounting for approximately 83% of all strokes. An ischemia is an insufficient supply of blood to an organ, which is typically caused by a blocked artery (blood vessel that carries blood from the heart to the rest of the body). Ischemic strokes occur when a blood clot interrupts or severely reduces the flow of blood to the brain.

Hemorrhagic stroke

Hemorrhagic strokes account for approximately 17% of all strokes. They occur when a weakened blood vessel ruptures in or around the brain and damages the surrounding brain tissue. Hemorrhagic strokes are more likely to cause permanent disability and result in death than ischemic strokes.

Transient ischemic attack (TIA)

A transient ischemic attack ("mini-stroke") is a minor stroke. TIAs occur when a blood clot temporarily obstructs blood flow to the brain. The symptoms of a transient ischemic attack develop but aren't long lasting (up to 24 hours). Although TIAs usually don't cause permanent disability, they are considered a risk factor for a future major stroke.

A stroke is a medical emergency. Early treatment helps:

Minimize brain damage.
Reduce disability.
Save lives.

According to the Centers for Disease Control and Prevention (CDC), in the United States:

Stroke is the third leading cause of death. Heart disease is the first.
Over 160,000 people die each year from stroke.
Stroke is a leading cause of serious long–term disability.
Approximately 700,000 strokes occur annually.
- 500,000 of these are first or new strokes.
- 200,000 occur in people who have had a prior stroke.

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