Syncope

Background

• 3 Questions

1. Is this true syncope or something else (eg, stroke, seizure, head injury)?
2. If this is true syncope, is there a clear life-threatening cause?
3. If this is true syncope and the cause is not clear, is the pt at high risk?

• Cardiac syncope usually occurs w/o warning
• TIA unlikely if no other s/s before or after
• In elderly think MI until proven otherwise

Risk Factors for Serious Cause

1. Exertion preceding the event
2. History of cardiac disease in the patient
3. Family history of sudden death, deafness, or cardiac disease
4. Recurrent episodes
5. Recumbent episode
6. Prolonged loss of consciousness
7. Associated chest pain or palpitations
8. Use of medications that can alter cardiac conduction

San Francisco Syncope Rule

• 1.4% of patients who are rule-negative will have a 7-day serious outcome
• 10% of patients meeting the below criteria will have a 7-day serious outcome

Criteria (CHESS Pneumonic)

• CHF History
• Hct < 30%
• ECG Abnormality
• SOB history
• SBP < 90mmHg at triage

Work-Up

1. ECG
2. Urine pregnancy
3. Consider:
   1. Hemoglobin
   2. Chemistry
   3. Orthostatics (symptomatic)
   4. CXR (dissection)
   5. Troponin
   6. Guaiac

DDX

Etiology is divided into 3 major categories:

1. Cardiovascular-mediated syncope
2. Neurally mediated syncope
3. Orthostatic hypotension-mediated syncope

• Cardiovascular-mediated syncope:
  • Dysrhythmias:
    • WPW (pre-excitation)
    • Long QT syndrome
    • Brugada syndrome
    • 2nd/3rd degree AV block
    • Afib/aflutter
    • Vtach/torsades
    • Sick sinus syndrome
  • Cardiovascular disease:
    • Valvular disease (AS, MS, tricuspid stenosis)
    • Aortic dissection
    • Myocardial infarction
    • CHF
    • PE
    • Pericardial tamponade
    • Myxoma
    • Pulmonary HTN
• Neurally mediated syncope:
  • Vasovagal:
    • Fear, pain, emotion, valsalva, breath-holding spell
  • Situational (associated with):
    • Coughing, micturition, defecation, vomiting
    • Carotid sinus stimulation
• Orthostatic hypotension-mediated syncope:
  • Volume depletion:
    • Dehydration (vomiting, diarrhea)
    • Hemorrhage
    • Sepsis
  • Autonomic dysreflexia
  • Autonomic failure due to meds
• Other serious causes:
  • SAH
  • TIA
  • Subclavian steal

Source

Tintinalli

Treat

1. Treat cause
   1. See also Hypotension

Disposition

1. Admit
   1. Abnormal ECG
   2. CHF
   3. Suspicion of structural heart disease
   4. HCT <30
   5. Shortness of Breath
   6. SBP <90
   7. Family history of sudden cardiac death
   8. Advanced age
2. Discharge
   1. None of the above findings (esp if age <45)
   2. Consider referral for holter or til-table test

Source

• Tintinalli
• UpToDate
• ACEP Clinical Policy 2007
• The NNT (http://thennt.com/risk/syncope-in-the-emergency-department)