causes of syncope

Etiology

• cardiac
  • aortic stenosis
  • pulmonary embolism
  • atrial myxoma
  • pulmonary hypertension
  • atrioventricular block
  • pulmonic stenosis
  • hypertrophic cardiomyopathy
  • sick sinus syndrome
  • mitral stenosis
  • supraventricular tachycardia
  • myocardial infarction
  • ventricular tachycardia
  • paroxysmal ventricular fibrillation associated with
    • prolonged QT interval
    • Wolf-Parkinson-White syndrome
    • Brugada syndrome
    • commotio cordis
• pharmaceutical agents*
  • antiarrhythmic agents
  • digitalis
  • anticonvulsants
  • diuretics
  • antihypertensive agents
  • narcotics
  • antipsychotics
  • nitrates
  • beta-blockers
  • tricyclic antidepressants
• neurally-mediated disturbance of blood pressure control
  • carotid sinus syndrome
  • cough
  • micturition syncope
  • psychogenic causes
  • gastrointestinal events
    • defecation*
    • swallowing
    • postprandial hypotension*
  • vasovagal syncope
• neurologic & psychiatric
  • anxiety disorder
  • panic attack
  • cerebrovascular spasm
  • seizure
  • depression
  • subclavian steal
  • migraine
  • vertebrobasilar ischemia
  • narcolepsy
• orthostasis
  • drugs
  • venous pooling
  • autonomic insufficiency
  • intravascular volume depletion
  • decreased reflex peripheral vasoconstriction
• miscellaneous
  • hyperventilation
  • hypoglycemia
  • hypoxia
  • thyroid disease

* combination of hypotensive medications taken with meals with subsequent effect of Valsalva maneuver during defecation is common cause of syncope in elderly

Pathology

• underlying pathology is total cerebral hypoperfusion

Additional terms

• syncope