What is a Stroke?
A stroke – or brain attack – is a type of cerebrovascular disease that affects the body's ability to carry blood to the brain. In order to function, the brain needs a constant flow of blood which travels through your arteries (also known as blood vessels). If the blood flow is blocked and the brain cannot get the level of oxygen-rich blood it needs, then the deprived area of the brain begins to die.
Stroke is a medical emergency. It is the leading cause of adult disability and the third-leading cause of death in the United States. Prompt treatment of a stroke could mean the difference between life and death. Early treatment can also minimize damage to your brain and future disability.
Stroke Signs and Symptoms:
- Sudden numbness, weakness, or paralysis of your face, arm or leg, usually on one side of your body
- Loss of speech (i.e. trouble speaking or understanding speech)
- Sudden blurred, double or decreased vision
- Dizziness, loss of balance or loss of coordination
- Difficulty swallowing
- Confusion, or problems with memory, spatial orientation or perception
- Seizures, fainting or blacking out
- A sudden, severe headache or an unusual headache, which may include vomiting or altered consciousness
Knowing the signs of a stroke, calling 9-1-1 immediately and getting to the hospital are critical. Available treatments are time sensitive.
For most people, a stroke gives no warning. But one possible sign of an impending stroke is a transient ischemic attack (TIA), sometimes known as a "mini-stroke." A TIA is a temporary interruption of blood flow to a part of your brain. The signs and symptoms of TIA are the same as for a stroke, but they last for a shorter period — several minutes to 24 hours — and then disappear, without leaving obvious effects. You may have more than one TIA, and the recurrent signs and symptoms may be similar or different. A TIA indicates a serious underlying risk that a full-blown stroke may follow. People who have had a TIA are ten times more likely to have a stroke as are those who haven't had a TIA.
Types of Stroke
An Ischemic stroke occurs when an artery in the brain is blocked. The most common cause is narrowing of the arteries due to atherosclerosis (gradual cholesterol deposits). When the arteries are narrowed, blood cells accumulate and form blood clots (thrombosis). Another cause of stroke is a blood clot in the heart (embolism) from irregular heartbeat (atrial fibrillation), heart attack or abnormal heart valves.
Hemorrhagic stroke is most often caused by high blood pressure which stresses the artery walls, causing it to burst and bleed to the surrounding brain tissue.
An intracerebral hemorrhage occurs when there is bleeding within the brain tissue. The primary cause of this type of hemorrhage is high blood pressure (hypertension).
Subarachnoid hemorrhage is bleeding that occurs in the area between the brain and the thin tissue layer that surrounds it. This is usually caused by an aneurysm, which is a weak or thin spot on a blood vessel wall. Some aneurysms are present at birth and others develop over a number of years and are usually not detected until they burst.