What Is Stroke?

A stroke is a type of brain injury, an attack, caused by sudden interruption of the blood flow to the brain. This interruption of blood flow can occur when a blood vessel is either blocked by a blood clot or plaque. Plaque is the buildup of cells, fat and cholesterol in a blood vessel that can develop over time, gradually decreasing the flow of blood to the brain until finally an occlusion occurs. This same situation can occur in the blood vessels of the heart, leading to a heart attack.

A stroke can also occur when a blood vessel in the brain ruptures. This is known as a cerebral hemorrhage. Whether the interruption of blood flow is due to an occlusion or a ruptured blood vessel, the results are the same. Blood cannot reach the brain; brain cells become deprived of oxygen and die.

Many times strokes are preceded by temporary episodes of stroke symptoms that last only a few minutes. These are called TIAs or transient ischemic attacks. They should not be ignored. Approximately 35 percent of persons who experience these symptoms will have a stroke within five years.

Four areas of brain function can be affected by stroke:

• Motor control - arm and leg movements and swallowing
• Sensation - sound, sight, touch
• Communication and Cognition - talking and understanding the spoken/ written word
• Personality - moods and emotions 

According to the American Stroke Association, about 600,000 Americans will have a stroke this year and 160,000 of them will die. In fact, stroke is our nation's number 3 killer and one of the leading causes of long-term disability in adults. If you have symptoms, seek medical attention promptly.