A stroke may occur if an artery bursts or is blocked. This may prevent blood flow to the brain.
Your brain gets blood mainly through:
These four arteries branch into other blood vessels that supply your brain with blood.
If blood cannot flow to your brain, your brain cells will start to die. Stroke symptoms will start to appear.
There are two types of stroke: ischemic and hemorrhagic.
This type of stroke happens when a blood vessel in the brain is blocked. This may be caused by a blood clotting disorder. There are two types of ischemic stroke:
In more severe strokes, the large arteries in your brain or neck may be blocked. This blockage may cause permanent injury to a large part of the brain.
Ischemic strokes may lead to widespread brain injury. This injury can cause swelling in the brain. This swelling may lead to severe disability or death.
A thrombotic stroke occurs when plaque narrows artery walls and reduces blood flow to the brain.
An embolic stroke occurs when a small blood clot blocks a blood vessel.
A thrombotic or embolic ischemic stroke may be called a TIA.
TIAs have the same symptoms as a stroke but they do not cause brain injury. They are sometimes called mini-strokes. If you had a TIA, your stroke risk is higher.
Important: TIAs require the same immediate attention as a stroke.
This type of stroke happens when a blood vessel in the brain ruptures and bleeds. This may be caused by a blood clotting disorder. There are two types of hemorrhagic stroke:
Do not ignore symptoms of a TIA.
Call 911 right away.
A blood clotting disorder occurs when you have abnormal amounts of different proteins in your blood that can:
Certain diseases and medicines can also affect how blood clots.
Atrial fibrillation is an irregular heartbeat. Your heart's upper chambers quiver instead of beat in a regular rhythm. Blood pools in your heart and can form blood clots. This increases your risk of having a stroke.