When somebody has astroke, it means that some part of their brain tissue has died.
Stroke is usually brought on by the interruption of blood flow to part of the brain.
Up to 40% of the time, however, no specific cause for the stroke can be identified.
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A stroke whose cause remains unknown after a thorough evaluation is called a cryptogenic stroke.
(The term cryptogenic simply means that the cause is cryptic, or perplexing.)
When Are Strokes Called Cryptogenic?
A stroke should not be called cryptogenic until afull medical evaluationhas failed to reveal a specific cause.
However, cryptogenic stroke remains a fairly common diagnosis.
Who Gets a Cryptogenic Stroke?
They tend to be older individuals who have the typical risk factors for cardiovascular disease.
Cryptogenic strokes are seen equally in men and women.
They may be more common in Blacks and Latinx people.
Still, the two-year rate of recurrent stroke after a cryptogenic stroke averages 15% to 20%.
The consensus among experts at this point, however, leans toward using antiplatelet therapy.
Undoubtedly, some cryptogenic strokes are produced by blood clots that cross a PFO and travel to the brain.
However, this phenomenon is quite rare, while PFOs are very common.
(PFOs can be identified in up to 25% of all individuals by echocardiography.)
No reduction in subsequent strokes has been identified.
It is still likely that in certain patients, closing PFOs would probably be beneficial.
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American Stroke Association.Understanding diagnosis and treatment of cryptogenic stroke.
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