1. W. Kissinger Tintinalli Sixth Edition Chapter 52
Syncope
W. Kissinger
Tintinalli Sixth Edition
Chapter 52

2. Syncope
a sudden, transient loss of consciousness associated with inability to maintain postural tone.

3. Pathophysiology Final Pathway
Lack of vital nutrient delivery to the brainstem reticular activating system
loss of consciousness and postural tone

6. Pathophysiology #1 #2 Drop in cardiac output Vasospasm
Decrease in oxygen and substrate delivery to the brain #2
Vasospasm

7. Etiology Cardiac dysrhythmia Vasovagal reflex-mediated
Orthostatic hypotension

8. Normal Response Physical or emotional stress
 increased sympathetic outflow
 increase in heart rate, blood pressure, and cardiac output

9. Reflex-Mediated Syncope
Abnormal autonomic nervous system reflex
Inappropriate withdraw of sympathetic tone and replacement with increased vagal tone
Vagal hyperactivity

10. Reflex-Mediated Syncope
Vasovagal
Situational
Carotid sinus hypersensitivity

11. Orthostatic Syncope Insufficient autonomic response ☼Normally☼
Upright posture blood shifted to lower extremity cardiac output drops increase in sympathetic output and decrease in parasympathetic output ↑ HR and PVR ↑ CO and BP

13. Orthostatic Syncope Autonomic dysfunction Primary disease process
Secondary to the following:
Peripheral neuropathy
Medications
Spinal cord injury

14. Orthostatic Hypotension
Defined by the consensus group of the American Autonomic Society as a sustained decrease in blood pressure exceeding 20 mmHg systolic or 10 mmHg diastolic occurring within 3 minutes of upright tilt.

15. Orthostatic Syncope
Should have recurrence of syncopal symptoms on orthostatic testing
Warning: 5-55% of patients with other causes of syncope have orthostatic hypotension on exam

16. Cardiac Syncope
Heart is unable to provide adequate cardiac output to maintain cerebral perfusion
Dysrhythmias
Associated with underlying structural disease
Structural cardiopulmonary lesions

17. 25 y/o presents after a syncopal event with the following EKG

19. 25 y/o presents after a syncopal event with the following EKG

20. Long QT syndrome
Normal interval is 0.42 seconds

21. Cardiac Syncope If caused by a dysrhythmia:
Typically sudden (prodromal symptoms lasting less than 3 seconds)
Subjectively lack warning

22. Underlying Cardiopulmonary Structural Disease
Aortic Stenosis (listen for the murmur)
Chest pain, DOE, and syncope
Pulmonary Embolism
Hypertrophic cardiomyopathy

23. Medications Β-blockers and calcium channel blockers Diuretics
Blunted heart rate response after orthostatic stress
Diuretics
Volume depletion and orthostatic hypotension
Antipsychotics
Proarrhythmic properties

24. Psychiatric Illness Generalized anxiety disorder
Major depressive disorder
Typically young, repeated episodes, multiple prodromal symptoms and a positive review of symptoms

25. Neurovascular Syncope
Brainstem ischemia causing a decrease in blood flow to the reticular activating system
S/S of posterior circulation ischemia
Diplopia, vertigo, nausea

26. Question???
25 year old left-handed male presents to the ED after a syncopal event while painting a fence. You note he has unequal blood pressures in his upper extremities (right>left).
Diagnosis?

27. Subclavian Steal Syndrome
Abnormal narrowing of the subclavian artery proximal to the origin of the vertebral artery

28. Emergency Department Evaluation
Goal: Identify those at risk for immediate decompensation and those at future risk of serious morbidity or sudden death.
History
Physical Exam
EKG

29. Easy Task?!?!?! Just rule-out the following:
AMI PE
aortic dissection
cardiac tamponade
tension pneumothorax
leaking AAA
active internal bleeding
malignant cardiac arrhythmias
ectopic pregnancy
SAH
carotid artery/vertebral artery dissection
air embolism

30. History Patient and witnesses Events Duration/Symptoms
Past medical history
Medications
Family history

31. Physical Examination Trauma without defensive injuries
Cardiovascular system
Murmur
Unequal blood pressures
Orthostasis
Neurologic system
Focal neurologic findings
Rectal Exam

32. History, Physical and EKG. . . .

33. EKG Prior cardiopulmonary disease Acute ischemia Dysrhythmia
Heart block
Prolonged QT

34. Lab Testing
Dictated by H & P
CBC
Pregnancy test
Electrolytes

35. Disposition
Should they stay or should they go?

36. ACEP Task Force Recommendations
Admit patients with syncope and any of the following:
1. A history of congestive heart failure or ventricular arrhythmias 2. Associated chest pain or other symptoms compatible with acute coronary syndrome 3. Evidence of significant congestive heart failure or valvular heart disease on physical     examination 4. ECG findings of ischemia, arrhythmia, prolonged QT interval, or bundle branch block

37. ACEP Recommendations
Consider admission for patients with syncope and any of the following:
1. Age older than 60 years 2. History of coronary artery disease or congenital heart disease 3. Family history of unexpected sudden death 4. Exertional syncope in younger patients without an obvious benign etiology for the     syncope

38. Predictors of Sudden Cardiac Death or Significant Dysrhythmia
1. Abnormal EKG
2. Age older than 45 years
3. History of ventricular dysrhythmia
4. History of congestive heart failure

39. European Heart Journal, May 2003
Development and Prospective Validation of a Risk Stratification System for Patients With Syncope in the ED: The Oesil Risk Score
270 pts (syncope w/u: H&P, 12 lead, glucose, hgb) followed one year
Four independent risk factors: >65 years, hx cardiovascular dz, syncope w/o prodrome, abnormal EKG
1 ( %) (52.9%)

40. Academic Emergency Medicine Dec 2003
A Risk Score to Predict Arrhythmias in Patients with Unexplained Syncope
<65 years, normal EKG, no Hx of CHF
0 (2%), 1 (17%), (27%)

41. Questions 1. The most common cause of syncope is
A. Orthostatic hypotension
B. Vasovagal
C. Cardiac dysrhythmia
D. Situational

42. Questions
2. Classic symptoms of orthostatic syncope include all of the following except
A. Blurred Vision
B. Dizziness
C. Vertigo
D. Tunnel Vision

43. Questions
3. The classic presentation of Syncope from aortic stenosis include.
A. Chest Pain
B. Syncope
C. Dyspnea on exertion
D. Palpitations

44. Questions
4. Which on of the following criteria according to Tintinalli define Orthostatic Hypotension
A. Increase in HR > 20 BPM
B. Decrease in Systolic BP of 10mmHg
C. Decrease in Systolic BP of 20mmHg
E. A and C
F. A and B

45. Questions
5. T or F Bradycardia is most likely to be a incidental finding in syncope
6. T or F In cardiac syncope the typical prodrome last no more than 3 minutes
7. T or F Subclavian Steal syndrome is more common on the Left

46. Answers
1. B
2. C
3. D
4. C
5. T
6. F
7. T