Posterior Cerebral Artery Infarction Health Channel

Definition

A stroke is an interruption of the blood supply to any part of the brain. A stroke is sometimes called a "brain attack."

See also:

• Arteriovenous malformation (AVM)
• Hemorrhagic stroke
• Stroke secondary to carotid dissection (bleeding from the carotid arteries)
• Stroke secondary to carotid stenosis (narrowing of the carotid arteries)
• Stroke secondary to cocaine use
• Stroke secondary to FMD (fibromuscular dysplasia)
• Stroke secondary to syphilis

Alternative Names

Cerebrovascular disease; CVA; Cerebral infarction; Cerebral hemorrhage; Ischemic stroke; Stroke - ischemic

Causes, incidence, and risk factors

Approximately every 40 seconds, someone in the United States has a stroke. A stroke can happen when the following occurs:

• A blood vessel that supplies blood to the brain is blocked by a blood clot. This is called an ischemic stroke.
• A blood vessel breaks open, causing blood to leak into the brain. This is called a hemorrhagic stroke.

If blood flow is stopped for longer than a few seconds, the brain cannot get blood and oxygen. Brain cells can die, causing permanent damage.

ISCHEMIC STROKE

Ischemic stroke is the most common type of stroke. Usually this type of stroke results from clogged arteries, a condition called atherosclerosis. (See: Stroke secondary to atherosclerosis) Fat, cholesterol, and other substances collect on the wall of the arteries, forming a sticky substance called plaque. Over time, the plaque builds up. This often makes it hard for blood to flow properly, which can cause the blood to clot. There are two types of clots:

• A clot that stays in place in the brain is called a cerebral thrombus.