Stroke occurs when there is insufficient blood flow to the brain.
This may occur for a variety of reasons. The mechanisms of damage to the brain in stroke are similar to those on the heart in a heart attack. Stroke is the leading cause of disability and the third leading cause of death among adults in the United States with over 730,000 strokes occurring each year. There are approximately 3 million stroke survivors in the United States. The importance of immediate medical care for persons experiencing stroke is now widely recognized.