There are two main types of stroke.
Ischaemic strokes happen when there is a blockage in an artery that carries blood to the brain.
There are several possible causes:
- a blood clot forms in a main artery to the brain
- a blood clot, air bubble or fat globule forms in a blood vessel and is carried to the brain
- there is a blockage in the tiny blood vessels deep inside the brain.
Haemorrhagic strokes happen when a blood vessel bursts and bleeds into the brain (a haemorrhage).
The haemorrhage may be due to:
- a vessel bursting within the brain itself, or
- a blood vessel on the surface of the brain bleeding into the area between the brain and the skull.
Temporary symptoms may indicate a Transient Ischaemic Attack (TIA) or mini stroke
The symptoms of a TIA are the same as for a stroke but only last from between a few minutes to a few hours and then completely disappear within 24 hours.
Never ignore a TIA as it is a serious warning sign that there is a problem with the blood supply to your brain.
There is about a one in 10 chance that people who have a TIA will experience a full stroke.
If you have had a TIA, you must contact your GP, local hospital or out-of-hours service immediately.
You can recognise a TIA using the FAST test.
A TIA is still a medical emergency, because it can lead to a major stroke. If a person fails any part of the FAST test, get help immediately by dialling 999 and asking for an ambulance