Contents:
- Medical Video: Brain Stroke, Types of, Causes, Pathology, Symptoms, Treatment and Prevention, Animation.
- How is blood flow interrupted?
- Blood clots
- Thrombus
- Embolus
- Bleeding
- Hypoperfusion
- What are the common causes of stroke?
Medical Video: Brain Stroke, Types of, Causes, Pathology, Symptoms, Treatment and Prevention, Animation.
Stroke is an injury to the part of the brain due to impaired blood flow. What causes this blood flow to be disrupted?
The most common cause of stroke is blockage of blood flow in blood vessels in the brain. Arteries located in the neck and in the brain supply blood to the brain to keep functioning. This blood provides oxygen and nutrients needed for the brain to produce the biochemical energy needed to maintain life and carry out normal activities.
When blood flow in a blood vessel is blocked, an area in the brain experiences oxygen deficiency and lack of essential nutrients. This condition is called ischemia. The direct consequence of lack of blood causes certain areas of the brain to decrease function. If the lack of blood flow occurs very briefly, and then returns to recovery, then this condition is called reversible stroke, also called TIA or mini stroke. If the blood flow does not recover quickly, the injury will become more diffuse, perhaps permanent, causing a stroke.
How is blood flow interrupted?
Blood clots
Impaired blood flow can occur due to a blood clot called a thrombus or embolus. This causes an ischemic stroke.
Thrombus
Thrombus is a partial or complete blockage of the arteries due to blood clots.
Embolus
Embolus is frozen blood that initially forms in the arteries and then thickens and flows to reach the arteries in the brain and causes blockages and damage in the brain.
Bleeding
Other causes of stroke are processes that result in impaired blood flow due to bleeding in the brain.
When blood vessels are damaged, leakage of blood will irritate brain tissue and lack of blood supply. Stroke caused by bleeding from a leaky or damaged blood vessel is a condition of hemorrhagic stroke.
Hypoperfusion
Low blood supply to the brain is a less common cause of stroke. When the volume of fluid or blood in the body is very low, the brain cannot receive enough blood. Even though there are no blood clots in this condition, the brain suffers because the area of the brain that normally receives blood from arterial blood vessels may not receive enough blood supply. Stroke due to a low blood supply is usually called a watershed stroke. Certain areas of the brain are more susceptible to stroke watersheds.
What are the common causes of stroke?
The causes of stroke in the brain include:
- Cerebrovascular disease
- Aneurysm. This is the condition of arterial damage. Aneurysms can be a condition of leaking or rupturing in an artery that causes bleeding.
- AVM / arteriovenous malformation. This condition is a group of interconnected blood vessel defects, usually occurring in arteries and veins. The AVM condition can be a rupture of a blood vessel or the formation of a thrombus which causes a hemorrhagic stroke or ischemic stroke.
- Vasospasm. This condition is when the arteries suddenly spasm, disrupting blood flow and causing ischemia even without blood clots.
Causes of heart stroke include:
- Arrhythmias, aka irregular heartbeats such as untreated atrial fibrillation, can cause blood clots to form and cause the embolus to flow to the brain.
- Heart attacks, can cause dwn watershed infarction can also cause the embolus to flow to the brain.
- Carotid artery disease. This condition is a disease and clotting in a blood vessel located in the neck that supplies blood to the brain. The embolus in the carotid artery or blockage of the carotid artery can cause a stroke.
- Hypertension. This condition contributes to cerebrovascular disease, carotid artery disease, and heart disease. In addition, hypertension that occurs suddenly can cause vasospasm or bleeding from aneurysms.
Systemic causes of stroke include:
- Hypotension. Can occur due to heavy blood loss or dehydration, leading to brain hypoperfusion and watershed stroke.
- Medications that affect blood clotting, bleeding or blood pressure can also cause strokes.
- Illegal drugs such as cocaine, methamphetamine and other powerful stimulant drugs can cause vasospasm in every artery in the body. This can cause heart attacks, strokes due to cerebral artery vasospasm or blood clots that can flow to the brain and cause strokes.
- Blood clotting disorders can cause increased blood clot formation or increased bleeding.
- Infection can change the susceptibility of blood clots or susceptibility to bleeding leading to thrombus, embolus or bleeding. In rare cases, infectious organisms can physically block blood vessels, causing ischemia.
- Inflammation can contribute to increased blood clotting.
- An air embolus is an air bubble that goes to the brain from another place in the body, blocks blood vessels, and causes strokes.
