A stroke is a medical emergency when blood supply to the brain is interrupted and causes damage to the brain.
A stroke occurs when a blood vessel that carries oxygen and nutrients to the brain is either blocked by a clot or bursts (ruptures). When that happens, part of the brain cannot get the blood and oxygen it needs, and brain cells die.
There are three types of strokes:
Ischemic stroke: This is the most common type of stroke. It happens when the brain’s blood vessels become narrowed or blocked, causing ischemia (severely reduced blood flow).
Blocked or narrowed blood vessels are caused by fatty deposits that build-up in blood vessels or by blood clots that travel through the bloodstream and lodge in the blood vessels in the brain.
Haemorrhagic stroke: This stroke occurs when a blood vessel in the brain leaks or ruptures.
Factors related to haemorrhage stroke include:
- Uncontrolled high blood pressure
- Overtreatment with blood thinners (anticoagulant)
- Bulges at weak spots in the blood vessel walls (aneurysm)
- Trauma (such as car accident)
- Ischemic stroke leading to haemorrhage
Transient Ischemic Attack (TIA): TIA is sometimes known as a ministroke. It does not cause permanent damage. TIA is caused by a temporary decrease in blood supply to part of the brain, which may last as little as five minutes. It occurs when a clot or debris reduces or blocks blood flow to part of the nervous system.