syncope

Syncope is a sudden transient loss of consciousness associated with loss of postural tone. "Blackout spells," "passing out," or "fainting" are terms occasionally used by patients and refer to syncope only if associated with loss of consciousness. (online source: Clinical Methods: The History, Physical, and Laboratory Examinations. 3rd edition. Walker HK, Hall WD, Hurst JW, editors.)

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See also: bradycardia