A stroke occurs when blood flow to a part of the brain stops. A stroke is sometimes called a "brain attack."
If blood flow is cut off for longer than a few seconds, the brain cannot get nutrients and oxygen. Brain cells can die, causing lasting damage.
There are two major types of stroke:
Ischemic stroke occurs when a blood vessel that supplies blood to the brain is blocked by a blood clot. This may happen in two ways:
Ischemic strokes may also be caused by a sticky substance called plaque that can clog arteries.
A hemorrhagic stroke occurs when a blood vessel in part of the brain becomes weak and bursts open. This causes blood to leak into the brain. Some people have defects in the blood vessels of the brain that make this more likely. These defects may include:
Hemorrhagic strokes may also occur when someone is taking blood thinners, such as warfarin (Coumadin). Very high blood pressure may cause blood vessels to burst, leading to hemorrhagic stroke.
An ischemic stroke can develop bleeding and become a hemorrhagic stroke.
High blood pressure is the main risk factor for strokes. The other major risk factors are:
Stroke risk is also higher in:
The symptoms of stroke depend on which part of the brain is damaged. In some cases, a person may not know that a stroke has occurred.
Most of the time, symptoms develop suddenly and without warning. However, symptoms may occur on and off for the first day or two. Symptoms are usually most severe when the stroke first happens, but they may slowly get worse.
A headache may occur if the stroke is caused by bleeding in the brain. The headache:
Other symptoms depend on how severe the stroke is and what part of the brain is affected. Symptoms may include:
The doctor will do a physical exam to:
You may have the following tests to help find the type, location, and cause of the stroke and rule out other disorders:
Other tests include:
A stroke is a medical emergency. Quick treatment is needed. Call 911 or your local emergency number or seek urgent medical care at the first signs of a stroke.
People who are having stroke symptoms need to get to a hospital as quickly as possible.
Other treatments given in the hospital will depend on the cause of the stroke. These may include:
Physical therapy, occupational therapy, speech therapy, and swallowing therapy will all begin in the hospital. If the person has severe swallowing problems, a feeding tube in the stomach (gastrostomy tube) will likely be needed.
The goal of treatment after a stroke is to help you recover as much function as possible and prevent future strokes.
Recovery from your stroke will begin while you are still in the hospital or at a rehabilitation center. It will continue when you go home from the hospital or center.
Support and resources are available from the American Stroke Association: www.strokeassociation.org.
How well a person does after a stroke depends on:
Problems moving, thinking, and talking often improve in the weeks to months after a stroke.
Many people who have had a stroke will keep improving in the months or years after their stroke.
Over half of people who have a stroke are able to function and live at home. Others are not able to care for themselves.
If treatment with clot-busting drugs is successful, the symptoms of a stroke may go away. However, patients often do not get to the hospital soon enough to receive these drugs, or they cannot take these drugs because of a health condition.
People who have a stroke due to a blood clot (ischemic stroke) have a better chance of surviving than those who have a stroke due to bleeding in the brain (hemorrhagic stroke).
The risk for a second stroke is highest during the weeks or months after the first stroke. The risk begins to decrease after this period.
Stroke is a medical emergency that needs to be treated right away. Call your local emergency number (such as 911) if someone has symptoms of a stroke.
Reducing your stroke risk factors lessen your chances of a having stroke.
Reviewed By: Joseph V. Campellone, MD, Division of Neurology, Cooper University Hospital, Camden, NJ. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.