No matter which of the possible causes underlie: In principle, a stroke results from a mismatch between blood and oxygen supply and demand. The brain is very active, which makes it very sensitive to oxygen deficiency. After just a few minutes, brain tissue is destroyed. Then there are corresponding, often irreparable failures.
Stroke: common causes
The most common cause is sudden circulatory disturbances - mainly due to insufficient blood flow in too narrow cerebral vessels, but also as a consequence of hemorrhage into the tissue. Other causes of stroke include injuries, brain inflammation or tumors.
Cause of acute hypoperfusion is - similar to a heart attack - usually a vascular occlusion as a result of many years of progressive atherosclerosis. This is also known as ischemic brain infarction. By deposits on the inner walls of the vessels, these are becoming ever narrower, it gets less and less blood in the brain areas and the blood flows more slowly. Therefore, more clots form, which then completely occlude the vessel (thrombosis), or the deposits dissolve small particles, which are further flushed with the bloodstream and also lead to closure (embolism).
Risk factors for a stroke
In addition, lead in such a pre-damaged vessels and blood pressure drops to supply difficulties, since not enough blood passes through our narrow arterial routes. In about 15-20% of all cases, the sudden rupture of a vessel leads to bleeding and consequently to tissue loss and its symptoms. This form of stroke is referred to as intracerebral mass haemorrhage.
The risk of a stroke is increased by all factors that also promote arteriosclerosis: especially high blood pressure, but also increased blood lipid levels, diabetes, smoking, high alcohol consumption, overweight, lack of exercise and taking birth control pills. In addition, atrial fibrillation is also a known risk factor. In addition, a hereditary susceptibility plays a role - in addition to age, the only factor that can not be influenced.