The Known and Unknown of Stroke Infographic

The known and unknown of stroke

The Known and Unknown of Stroke

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Each year 795,000 people in the U.S. have a stroke.2

Stroke is an interruption of blood flow to the brain. Without oxygen-rich blood, brain cells die.

Types of Stroke

  • Ischemic – Occurs when a clot or mass blocks a blood vessel, cutting off blood flow to a part of the brain.1, 2
  • Hemorrhagic – Occurs when a weakened blood vessel, like an aneurysm, ruptures and spills blood into the brain.1, 2

About 1/4 of ischemic strokes are classified as cryptogenic, meaning the cause is unknown.3

Finding the cause of a stroke is important because it helps reduce the risk of another stroke.


Possible Hidden Causes

  • Irregular heartbeat (Atrial fibrillation) – AFib patients are at a 5 times 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

Medtronic supports the American Stroke Association’s Cryptogenic Stroke Initiative.

1 - Benjamin EJ, et al. Circulation. 2019;139:e56–e528.

2 - Benjamin EJ, Blaha MJ, Chiuve SE, et al. on behalf of the AHA Statistics Committee and SS Subcommittee. Heart disease and stroke statistics—2017 update: a report from the AHA. Circulation. 2017;135:e229-e445.

3 - Saver, JL. Cryptogenic Stroke. N Engl J Med 2016;374:2065-74.