Syncope Differential Diagnoses

Updated: Jan 13, 2017
  • Author: Rumm Morag, MD, FACEP; Chief Editor: Erik D Schraga, MD  more...
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DDx

Diagnostic Considerations

There are well-publicized implications of patients with syncope returning to activities such as sports, driving, and operating machinery. Consultation with a subspecialist and/or a hospital attorney may be prudent prior to making definitive recommendations.

Elderly patients with dementia and episodes of suspected sycope may have an atypical clinical presentation and render it difficult to use a standard diagnostic protocol for syncope. [6] These patients also suffer frequent unexplained falls.

Note the following:

  • Consider and diagnose life-threatening etiologies of syncope
  • Scrutinize the initial electrocardiogram (ECG) and seek comparison to a prior ECG
  • Provide adequate subspecialty and/or primary care follow-up
  • Educate patients adequately about the etiology of the syncope and preventive measures to avoid recurrence
  • Adequately address short-term recurrence probability and ensure low risk of subsequent morbidity
  • Consider and diagnose life-threatening conditions that occur as a result of the syncopal episode

Vasomotor/vascular conditions to consider in patients with suspected syncope include the following:

  • Dehydration
  • Diuresis
  • Drug-induced orthostasis
  • Dysautonomia
  • Hemorrhage
  • Hypotension
  • Hypovolemia
  • Multisystem atrophy
  • Peripheral polyneuropathy
  • Postural hypotension
  • Vasodepressor/vasovagal response
  • Vasomotor insufficiency

Cardiac conditions to consider in patients with suspected syncope include the following:

Situational conditions to consider in patients with suspected syncope include the following:

  • Carotid sinus syncope
  • Cough (posttussive) syncope
  • Defecation syncope
  • Micturition syncope
  • Postprandial syncope
  • Swallow syncope

Metabolic/endocrine conditions to consider in patients with suspected syncope include the following:

Central nervous system conditions to consider in patients with suspected syncope include the following:

Differential Diagnoses