A stroke occurs when blood flow to part of the brain stops. It is sometimes called a “brain attack.” If blood flow stops, the brain cannot get blood and oxygen. This can cause brain cells to die and permanent damage.
There are two major types of stroke: ischemic stroke and hemorrhagic stroke. Ischemic stroke occurs when a blood vessel that supplies blood to the brain is blocked by a blood clot. Ischemic strokes are also caused by clogged arteries where fat, cholesterol, and other substances collect on the artery walls, forming a sticky substance called plaque. A hemorrhagic stroke occurs when a blood vessel in part of the brain becomes weak and bursts open, causing blood to leak into the brain. People with blood vessels defects in the brain are at a higher risk for a hemorrhagic stroke.
High blood pressure is the most common risk factor for stroke. Other risk factors include: Atrial fibrillation, diabetes, family history, high cholesterol, race, age (after 55), smoking, illegal drug use, obesity, high sodium consumption, and heavy drinking.
Birth control pills also increase the chance of blood clotting and stroke, and women over 35 and/or smoke have an elevated risk.
Symptoms usually develop suddenly and without warning. Sometimes, symptoms occur on and off for a day or two and the person may not even aware he or she is having a stroke. Symptoms are usually most severe when the stroke first happens, but they may slowly get worse.
Telltale signs you may be having a stroke include:
To a diagnosis a stroke, a doctor should check for problems with vision, movement, feeling, reflexes, understanding, and speaking and check to see if blood pressure is high. Doctors may also listen for an abnormal sound, called a "bruit," which is caused by abnormal blood flow.
Other tests that can help your doctor find the cause of the stroke are:
Angiogram of the head can show which blood vessel is blocked or bleeding
People who are having stroke symptoms should get to a hospital as quickly as possible. Immediate treatment can save lives and reduce disability. If a stroke is caused by a blood clot, a clot-busting drug may be given to dissolve the clot. Most of the time, patients must reach a hospital within 3 hours after symptoms begin, though some people may be able to receive these drugs for up to 4 - 5 hours after symptoms begin.
Treatment depends on the severity of the stroke and what caused it. Most people who have a stroke need to stay in a hospital for an extended period of time.