The Known and Unknown of Stroke Infographic
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Known
Each year 795,000 people in the U.S. have a stroke.1
Types of Stroke
Stroke is an interruption of blood flow to the brain. Without oxygen-rich blood, brain cells die.
Ischemic occurs when a clot or mass blocks a blood vessel, cutting off blood flow to a part of the brain.1
87% (Ischemic Stroke) / 13% (Hemorrhagic Stroke)
Hemorrhagic occurs when a weakened blood vessel, like an aneurysm, ruptures and spills blood into the brain.1
Finding the cause and secondary stroke risk factors are important because it helps your doctor develop a plan personalized for you to prevent another stroke.
Unknown
Possible Hidden Causes
While some patients may continue to have the cause of their stroke unknown, a cause or secondary stroke risk factors may be revealed with further testing.
Irregular heartbeat (Atrial Fibrillation) AFib patients are at a 5x greater risk for stroke.1
Heart structure problem (such as Patent Foramen Ovale)
Hardening of the arteries (Large Artery Atherosclerosis)
Blood clotting disorder (Thrombophilia)
Find the facts at stroke.org/unknowncause
1 - Virani SS, Alonso A, Aparicio HJ, et al. on behalf of the AHA Statistics Committee and SS SubcommitteHeart disease and stroke statistics-2021 update. Circulation. 2021;143:e254-e743
2 - Kleindorfer DO, Towfighi, Chaturvedi S, et al. 2021 Guideline for the Prevention of Stroke in Patients with Stroke and Transient Ischemic Attack: A Guideline from the American Heart Association/American Stroke Association. Stroke. 2021;52:e364–e467.