Stroke is a brain injury that occurs when the brain's blood supply is interrupted. Without oxygen and nutrients from blood, brain tissue starts to die within minutes. Tissue loss in the brain causes a sudden loss of function. Another term for stroke is cerebrovascular accident (CVA).
Like a heart attack, the early emergency treatment is given the better the recovery. Acute treatment is beginning to positive results if done within 4½ to 6 hours of the start of stroke.
The types of stroke include:
An ischemic stroke most often occurs when blood flow to the brain becomes blocked.
One of the following events may cause this blockage:
- The most common cause is a build-up of fatty substances along an artery's inner lining that causes it to narrow, reduces its elasticity, and decreases its blood flow.
- A clot forms in an artery supplying the brain, usually one affected by atherosclerosis . This clot is called a thrombus.
- Blockage can also be caused by a blood clot from another part of the body (often the heart) that breaks free. The clot travels to and becomes lodged in an artery supplying the brain. This clot is called an embolus, and the process is called embolism.
A stroke may also occur if a blood vessel breaks and bleeds into or around the brain. Hemorrhagic stroke is most common in young people. The leading causes of this type of stroke are:
Aneurysms predispose you to hemorrhagic stroke. An aneurysm is a weak spot in an artery that balloons out under pressure and can rupture, causing bleeding into the brain.
According to the Centers for Disease Control and Prevention, stroke has affected 6.2 million Americans. Along with heart disease and cancer, stroke is one of the leading causes of death. Ischemic type occurs more often—in about 87% of the cases—compared to hemorrhagic.What are the risk factors for stroke?What are the symptoms of stroke?How is stroke diagnosed?What are the treatments for stroke?Are there screening tests for stroke?How can I reduce my risk of stroke?What questions should I ask my doctor?What is it like to live with stroke?Where can I get more information about stroke?
- Reviewer: Rimas Lukas, MD
- Review Date: 12/2013 -
- Update Date: 01/13/2014 -