What is a stroke?
A stroke is a sudden interruption in the blood supply of the brain. Most strokes (about 80%) are caused by a sudden blockage of arteries leading to the brain (ischemic stroke). Other strokes are caused by bleeding into brain tissue when a blood vessel bursts (hemorrhagic stroke). Because stroke occurs rapidly and requires immediate treatment, stroke is also called a brain attack. Stroke has many consequences. To learn more about the signs and symptoms of stroke and its effects, please read the Stroke Heroes Act FAST page.
What is an acute stroke?
Acute stroke refers to a current blockage in a vessel to or in the brain that has just occurred (within hours of its onset). Prompt treatment improves the chances of survival and decreases disability that may be expected. A person who may have suffered a stroke should be seen in a hospital Emergency Department without delay. If given within three hours of when the person was last known to be well, a clot-busting drug called intravenous-tissue plasminogen activator (IV-tPA) can reduce long-term disability for ischemic stroke - the most common type of stroke. IV-tPA is the only medication approved for the treatment of acute stroke.
What is IV-tPA?
Intravenous Tissue Plasminogen Activator (IV-tPA) is a thrombolytic agent (clot-busting drug). It is approved for use in certain patients having a heart attack or stroke. The drug can dissolve blood clots, which cause most heart attacks and strokes. IV-tPA is the only drug approved by the U.S. Food and Drug Administration (FDA) for the acute, urgent treatment of ischemic stroke.
How does IV-tPA help people having a stroke?
IV-tPA has been shown to be effective in treating ischemic stroke, the kind of stroke that is caused by blood clots that block blood flow to the brain. In 1996 the U.S. Food and Drug Administration (FDA) approved the use of IV-tPA to treat ischemic stroke in the first three hours after the start of symptoms in eligible patients. (Note: Not all patients qualify for IV-tPA. The best way to determine if you qualify is to be assessed as soon as possible). It is very important for people who think that they are having a stroke to seek help immediately and call 911. If given promptly, IV-tPA can significantly reduce the effects of stroke and reduce permanent disability. IV-tPA is FDA approved only to be given to a person within the first three hours after the start of their stroke symptoms which is why it is so important for stroke patients to get to the hospital quickly.
What is "last known to be well"?
Sometimes it's easy to determine when stroke symptoms began especially if they are witnessed by another person. However, other times it may be difficult to establish when the symptoms of a stroke started. In these circumstances it is important to know when the patient was last known to be functioning normally (before their stroke symptoms started) to determine treatment and to reduce the risk of a complication with IV-tPA. This is known as the time "last known to be well," and it is the earliest possible time at which the stroke might have begun.