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CNI Stroke Program
Education & Information
Facts about Stroke
What is a Stroke?
 Strokes occur when a clot blocks blood flow to the brain or when an artery in the brain ruptures, resulting in uncontrolled bleeding. Brain cells critically depend on a consistent flow of oxygen and glucose rich blood. When this flow is interrupted by a stroke, brain cells begin to die. Because our body cannot replicate nerve cells, strokes can lead to permanent brain damage and disability.
The negative effects of stroke depend upon which part of the brain the stroke occurs in. Therefore, strokes produce a wide array of symptoms, including paralysis, inability to speak, memory loss, and loss of cognitive ability.
There are two main types of stroke:
Ischemic Stroke - Ischemic “clot-type” strokes, which make up 85% of all cases, occur when blood flow to the brain is blocked by a clot. Clots can form when blood platelets stick to the artery walls. This process can be accelerated by the buildup of cholesterol and other fatty acids on artery walls known as atherosclerosis. Atherosclerosis restricts blood flow by narrowing the blood vessels. These narrowed vessels are more prone to clotting than normal arteries.
Ischemic strokes can also occur when a blood clot forms in another part of the body, travels to the brain, and then becomes lodged in an artery. This is more common among patients with irregular heartbeat such as atrial fibrillation. Atrial fibrillation causes blood to pool and often clot in the atria before being pumped to the body. Ischemic strokes occur when those clots block smaller arteries in the brain.
Hemorrhagic Stroke - Hemorrhagic “bleed-type” stroke occurs when a blood vessel in the brain ruptures, spilling blood into the brain tissue or into the area surrounding the brain. While these strokes account for only about 15 percent of all strokes, they are responsible for more than 30 percent of all stroke deaths. The clinical signs and symptoms vary for different types of stroke, and a physician’s treatment recommendations will vary accordingly. Treatment options include a variety of medical and surgical techniques that are determined based on the exact cause and size of the stroke. There are two types of hemorrhagic strokes:
- Subarachnoid Hemorrhage (SAH) - This type of hemorrhagic stroke occurs when blood vessels around the brain’s surface and under its protective layer leak, damaging these areas. This is most often results from a ruptured aneurysm, or weak spot in a vessel wall. SAH is often causes “the worst headache of my life” as well as nausea and vomiting and intolerance to light.
- Intracerebral Hemorrhage (ICH) - The most common type of hemorrhagic stroke, ICH, occurs when a blood vessel inside the brain ruptures, causing blood to leak into and damage the surrounding brain tissue. This can cause swelling and increased pressure within the brain. ICH accounts for 10-15 percent of all strokes.
There's another type of stroke called Transient Ischemic Attacks, or TIAs. A TIA is a brief episode of stroke-like symptoms that results from a temporary blockage of a blood vessel in the brain. The symptoms of a TIA are the same as stroke. TIAs can last anywhere from a minute up to a day. While TIAs do not cause any permanent brain damage, they often act as a warning sign for stroke. People who have experienced a TIA are ten times more likely to have a stroke. If you experience a TIA, it is important that you immediately see a doctor to help manage your risk of stroke.
Signs and Symptoms
The ability to treat stroke is directly related to how quickly a patient is admitted after the stroke occurs. Therefore it is critical to quickly recognize when a person is having a stroke. There are many symptoms of stroke such as:
- Numbness on one side of the body
- Difficulty speaking or understanding
- Change in vision
- Loss of balance or dizziness
- Severe headaches.
Act FAST!
Stroke is treatable. It is simple to remember to act FAST.
FACE - Does the FACE look uneven? Ask them to smile…
ARM – Does one arm drift down? Ask them to raise both arms…
SPEECH – Does their speech sound strange? Ask them to repeat a simple phrase…
TIME – Every second, brain cells die.
CALL 9-1-1 at ANY sign of stroke!
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