Stroke Causes
There are two types of stroke.
Ischaemic Strokes
An ischaemic stroke is the most common type, and is caused by a blockage in an artery, which prevents blood getting to part of the brain. Most ischaemic stroke causes are blood clots in the arteries supplying blood to the brain. This clot may form in an artery in the brain itself, or a clot that has formed in a larger artery in the chest or neck may break away, and be carried by the bloodstream until it becomes lodged in a smaller artery in the brain. The clots tend to form in arteries that are narrowed by a long-term build up of cholesterol and other fats in the artery wall. This gradual clogging is known as atherosclerosis, and is the same process that can lead to heart attack if it occurs in the arteries supplying the heart.
Haemorrhagic Strokes
The cause of a haemorrhagic stroke is the rupture of an artery in the brain, which leads to bleeding and squashing of the surrounding tissue. This type of stroke is often related to high blood pressure and/or diseases involving the blood vessels of the brain.