A stroke (cerebrovascular accident) happens when there is a loss of blood flow to a section of the brain, which, in 87% of cases occurs due to blood clot (ischemic stroke) and in 13% of cases occurs due to bleeding in the brain (hemorrhagic stroke). When blood flow is lost, not enough oxygen and nutrients get to brain cells, which start to die in minutes. Strokes that are not caught and treated quickly can result in death, brain damage, and/or disability. Sometimes, stroke symptoms will resolve within minutes to hours of onset; this is known as a transient ischemic attack (TIA) and is a strong risk factor for stroke. [1]
What is a stroke?
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•Last Updated: May 16, 2025
A stroke, or cerebrovascular accident, occurs when blood flow to a part of the brain is lost, primarily due to a blood clot (ischemic stroke) or bleeding (hemorrhagic stroke). This loss of blood flow can lead to brain cell death, which results in potential death, brain damage, or disability, and transient ischemic attacks (TIAs) indicate a heightened risk for future strokes.