Ischemic stroke is a variant of acute cerebrovascular disruption, in which the blood flow stops in one of the arteries that supply blood to the brain. The most common is an ischemic stroke of the brain, but it is possible and its development in the spinal cord, although it happens much less often.
Before the development of ischemic stroke, elderly and old age, smoking, and taking hormonal contraceptives are attracted.
In most cases, an ischemic stroke develops against the background of the following diseases:
- Arterial hypertension;
- Hypercholesterolemia and atherosclerosis;
- Heart disease (flashing arrhythmia, left ventricular aneurysm, myocardial infarction, cardiomyopathy, endocarditis and heart valve defects);
- Vasculitis (nodular periarthritis, Takayasu's disease, vasculitis with systemic lupus erythematosus and rheumatic fever);
- Antiphospholipid syndrome;
- Bundle of cerebral arteries and neck arteries with the formation of aneurysms;
- Blood disease (erythema, thrombocytosis).
This variant of an ischemic stroke develops against the background of atherosclerosis - a disease in which arteries in the wall accumulate fats and develop focal noninfectious inflammation, which leads to the formation of atherosclerotic plaque. The vessel is covered with fragments of an atherosclerotic plaque, which may be in the aorta, arteries of the head and neck.
The surface of the plaque, facing the lumen of the vessel, is represented by a thin membrane that is easily destroyed, izjazvlyaetsya, and plaque slices enter the bloodstream. The destruction of the plaque can occur with a sharp change in pressure inside the vessel. The atherothrombotic stroke occurs most often.
Often, an atherosclerotic plaque, whose surface is uneven or ligated, forms a thrombus. Thromb can block the vessel in the place of its formation, and may break away from the surface of the plaque and with the blood flow into the vessel of a smaller diameter. In the new place, further growth of the thrombus is possible.
In this type of stroke, the source of blood clots is the heart in which blood clots can be formed with flashing arrhythmia, myocardial infarction, and valve damage.
It develops at a sharp drop in blood pressure (for example, when overdose of antihypertensive drugs). Appears against the background of narrowing of the cerebral vessels or vessels of the neck with atherosclerotic plaques, aneurysm.
It develops quite rarely on the background of hypercoagulation with antiphospholipid syndrome, oral contraceptives, disseminated intravascular coagulation syndrome, polycythemia and other diseases that affect the viscosity and coagulation properties of the blood.
One third of cases of ischemic stroke occurs, it develops with the damage of small vessels in the background of diabetes mellitus and arterial hypertension. With these diseases, thickening of the arteriol wall or overlapping of its lumen occurs. Often found in the white matter of the brain, cerebellum, brain stem.
When the blood supply stops, necrosis of the nerve tissue occurs, and the damage becomes irreversible for several minutes: the metabolism of the nerve tissue greatly depends on the volume of blood flow.