Definition of Transient ischemic attack:

A transient ischemic attack (TIA) is when blood flow to a part of the brain stops for a brief period of time. A person will have stroke-like symptoms for up to 1-2 hours.

A TIA is felt to be a warning sign that a true stroke may happen in the future if something is not done to prevent it.

Causes, incidence, and risk factors:

A TIA is different than a stroke. After a TIA, the blockage breaks up quickly and dissolves. Unlike a stroke, a TIA does not cause brain tissue to die.

The loss of blood flow to an area of the brain can be caused by:

• A blood clot in an artery of the brain
• A blood clot that travels to the brain from somewhere else in the body (for example, from the heart)
• An injury to blood vessels
• Narrowing of a blood vessel in the brain or leading to the brain

High blood pressure is the number one risk for TIAs and stroke. The other major risk factors are:

• Atrial fibrillation
• Diabetes
• Family history of stroke
• High cholesterol
• Increasing age, especially after age 55
• Race (African Americans are more likely to die from stroke)

People who have heart disease or poor blood flow in their legs caused by narrowed arteries are also more likely to have a TIA or stroke.

See also: Stroke risk factors