A stroke is an interruption of the blood supply to any part of the brain. A stroke is sometimes called a "brain attack." There are two types of stroke: Ischemic stroke. The most common type of stroke. Usually results from clogged arteries (atherosclerosis.) Fatty deposits collect on the wall of the arteries, forming a sticky substance called plaque. Over time, the plaque builds up. Often, the plaque causes the blood to flow abnormally, which can cause the blood to clot.
There are two types of clots:
Cerebral thrombus - a clot that stays in place in the brain.2
Cerebral embolism - a clot that breaks loose and moves through the bloodstream to the brain. Causes of cerebral embolisms include: atrial fibrillation, endocarditis, an abnormal heart valve, and having a mechanical heart valve. A clot can form on a heart valve, break off, and travel to the brain. For this reason, those with mechanical or abnormal heart valves often must take blood thinners.
Hemorrhagic stroke: Bleeding in the brain that occurs when small blood vessels in the brain become weak and burst. Some people have defects in the blood vessels of the brain that make this more likely. The flow of blood after the blood vessel ruptures damages brain cells.
Signs & Symptoms
The symptoms of stroke depend on what part of the brain is damaged. In some cases, a person may not even be aware that he or she has had a stroke. Usually, a SUDDEN development of one or more of the following indicates a stroke:
Weakness or paralysis of an arm, leg, side of the face, or any part of the body
Numbness, tingling, decreased sensation
Slurred speech, inability to speak or understand speech, difficulty reading or writing
Swallowing difficulties or drooling
Loss of memory
Vertigo (spinning sensation)
Loss of balance or coordination
Mood changes (depression, apathy)
Drowsiness, lethargy, or loss of consciousness
Uncontrollable eye movements or eyelid drooping
If one or more of these symptoms is present for less than 24 hours, it may be a transient ischemic attack (TIA). A TIA is a temporary loss of brain function and a warning sign for a possible future stroke.
A stroke is a medical emergency. Physicians have begun to call it a "brain attack" to stress that getting treatment immediately can save lives and reduce disability. Treatment varies, depending on the severity and cause of the stroke. For virtually all strokes, hospitalization is required, possibly including intensive care and life support. The goal is to get the person to the emergency room immediately, determine if he or she is having a bleeding stroke or a stroke from a blood clot, and start therapy -- all within 3 hours of when the stroke began.