Syncope

1. Syncope 1. Definitions 2. Epidemiology 3. Etiology 4. Diagnostic Strategy 5. Disposition • James L. Wofford, MD, MS

2. Syncope - Quick take • Dangerous, disabling, and difficult to dx • Symptom, not a diagnosis • Rarely witnessed • The emergency is already over • No reference or gold standards for many tests

3. Syncope - Definitions • ACP 1997 - Transient loss of consciousness (LOC) with loss of postural tone, from which recovery is spontaneous • ACEP 2001- Sudden, transient LOC with inability to maintain postural tone and is distinct from seizure, coma, vertigo, hypoglycemia and other states of altered consciousness • ESC 2001 - Transient, self limited LOC with a relatively rapid onset and usually leading to falling; the subsequent recovery is spontaneous, complete, and usually prompt.

4. Syncope - Epidemiology • 3% of general population/yr • - Increases with age • - 1-6% of all hospitalizations/ED visits • 20% of pts. have recurrence within 1 yr • - 6% of recurrences assd with MVAs/fx • Increased mortality related to cardiac co-morbidity

5. Syncope - Epidemiology • Cardiac Syncope • 5 year mortality - 50% • 1 year mortality - 30% • Noncardiac Syncope • 1 year mortality - <6% • Unexplained Syncope • 1 year mortality - <6%

6. Syncope - Indications for Hospitalization • Indicated • -Hx of CAD, CHF, ventricular arrhythmia • -Accompanying sx of chest pain • -Physical signs of significant valve dz, CHF, stroke, or focal neuro dz • -EKG - ischemia, arrhythmia, QT problems, BBB • Often indicated • -Sudden LOC with injury, rapid heart action exertional syncope • -Frequent spells, suspicion of CAD or arrythmia, meds suspicious of Torsades • -Moderate-to-severe orthostatic hypotension

7. Is it really syncope? • dizziness • presyncope • vertigo • disequilibrium • lightheadedness • weak and dizzies • done fell out drop attack found down

8. Is it really syncope? Dizziness • Much more common than syncope • - 30% annual incidence in the elderly • - 1% of all clinic visits • Good prognosis • - 28% improve by 2 weeks • - majority improve by 1 year • Tests for syncope not often helpful • 80% of elderly have no specific identifiable cause

9. Is it really syncope? Seizure • Seizure - blue face (not pale), frothing, tongue biting, disorientation after event, aching muscles, LOC >5 min, slow return to nl mental statusSyncope - nausea or sweating before event, oriented after the event • PROBLEMS- Injury, tongue-biting, incontinence not useful in discriminating "fit" from "faint" - Sz activity in assn with LOC does not define a seizure as its cause (convulsive syncope)

10. Is it really syncope? Stroke • 6% of pts with TIA\stroke have LOC • posterior circulation - supplies the RAS - drop attacks • anterior circulation - would require bilateral compromise, only theoretically possible • need focal neuro sx\signs to use TIA as dx

11. Case #1 • 75yoWF admitted for syncopal episode. Brought to ED by daughter who reports declining functional status. Poor historian but claims no problems with palpitations, chest pain, SOB. Chief complaint - chronic low back and knee pain. • PMHX - osteoarthitis, osteoporosis - multiple vertebral fractures, HTN, mild cognitive impairment • MEDS Roxicodone BID, prn Vicodin, Xanax 0.5 TID, Fosamax 10 mg qD, Prempro qD, HCTZ 25 qD, amlodipine 5 qd • PE remarkable for weight 86#, normal BP, 2\6 SEM at LUSB, multiple bruises over forearms, inability to attend to task of answering questions.

12. Syncope - Mechanisms • global cerebral hypoperfusion • interruption of sympathetic outflow • increased vagal tone • other mechanisms - edema, cerebral autoregulation, central serotonin pathways The trigger for the switch in autonomic response remains one of the unresolved mysteries in cardiovascular physiology. Hainsworth. Syncope: what is the trigger? Heart 2003;89:123-124

13. Syncope - Mechanisms

14. Syncope - Mechanisms

15. What is wrong with this younger generation?

16. Syncope - Etiology • Old News- Diagnostic criteria not firmly established- Studies are poorly done, old and retrospective - selection bias - lack of diagnostic standardization • Recent reviewsAnnals 1997, N Engl J Med 1999 • New prospective studies • New Guidelines - European Task Force, 2001

17. Syncope - Etiology

18. Syncope - Etiology • Reflex mediated - 40% • Unexplained - 25% • Cardiac - 15% • Others - 20% • Hypoglycemia • Orthostatic hypotension • Medications • Psychiatric • Neurologic

19. Vasovagal Situational Other Carotid sinus Neuralgia Syncope - Etiology • Reflex mediated - 40% • Unexplained - 25% • Cardiac - 15% • Others - 20% • Metabolic • Orthostatic hypotension • Medications • Psychiatric • Neurologic

20. Mass Fainting at Rock ConcertsNEJM 1994;332;1721 • METHODS - Infirmary interview of 40 of the 4000 people who fainted during a concert by New Kids on the Block

21. Mass Fainting at Rock Concerts NEJM 1994;332;1721 • - All were girls between 11-17 YO- 40% reported having lost consciousness- Many still breathing rapidly backstage during interview • Reported combination provoking factors - sleeplessness during previous night - fasting since early AM while waiting in line - long periods of standing - hyperventilation (vasoconstriction) - Valsalva-like pressure • Interpretation - ROCK-CONCERT SYNCOPE - multifactorial pathophysiology- Preventive guidelines - sleep, sit, eat, keep cool, stay out of the crowd

22. Vasovagal Situational Other Carotid sinus Neuralgia Syncope - Etiology • Reflex mediated - 40% • Unexplained - 25% • Cardiac - 15% • Others - 20% • Metabolic • Orthostatic hypotension • Medications • Psychiatric • Neurologic

23. Case #2 • A 72-year-old man with recurrent dizziness, confusion, and syncope reported that cold, carbonated beverages caused him to feel strange, dizzy, and confused and might have triggered several episodes over a one-year study period. A carotid Doppler study, 24-hour Holter monitor, cranial MRI scan, CCT scan, and echocardiogram were unremarkable. An EEG showed diffuse slowing. Phenytoin was given but provided no improvement.

24. Case #2 Another internist evaluated the patient's condition and ordered a ETT and another MRI scan, which were negative. A cardiologist was consulted, and the results of a tilt-table test and coronary angiography were normal. After this evaluation, the patient drank a carbonated beverage while driving and wrecked his car.

25. Case #2 - A Pepsi Challenge New England J Med 1999;340:342 The patient was referred to me for further evaluation, and he gave the same history. Because the episodes were initiated reproducibly with cold, carbonated beverages, a can of Pepsi was given to the patient to drink while he was being monitored with an electrocardiograph. Abrupt bradycardia and hypotension developed, along with the patient's usual symptoms. Carotid-sinus massage was negative.

26. Case #3 - 55yoWM from Mount Airy, NC with first episode of syncope during shaving

27. Case #3 - 55yoWM from Mount Airy, NC with first episode of syncope during shaving

28. Vasovagal Situational Other Carotid sinus Neuralgia Syncope - Etiology • Reflex mediated - 40% • Unexplained - 20% • Cardiac - 20% • Others - 20% • Metabolic • Orthostatic hypotension • Medications • Psychiatric • Neurologic

29. Syncope – Diagnostic Strategy • History • Presyncopal • Positional, activities (exertional?), warning sx (palpitations), environment • Syncopal (witness) • Duration, seizure activity, skin color, diaphoresis, injury • Postsyncopal • Time to recovery • Past episodes , frequency of syncope • Past cardiac and other medical history • Medications

30. Syncope - Diagnostic Strategy • Alboni et al, 2001 • Best predictors of a cardiac cause • Patients with certain or suspected heart disease, syncope in supine position or during effort, blurred vision, convulsive synope • Only hx of heart disease is an independent predictor of cardiac cause of syncope (sens 95%, spec 45%)

31. Medications Associated with Syncope Syncope - Diagnostic Strategy • AntidepressantsAntiarrhythmicsAntihypertensivesBeta blockersCa blockersCardiac glycosidesDiuretics Nitrates Phenothiazines Recreational drugs Alcohol Cocaine Marijuana Hypoglycemics

32. Syncope - Diagnostic Strategy • Physical examination • complete • orthostatic hypotension - systolic change of 20 mm Hg - sitting BP unreliable • cardiovascular - difference in BP between arm • guiac • neurologic • carotid sinus**

33. 75YOWM nursing home resident in Mocksville, NC eating his favorite food macaroni TV dinner

34. 75YOWM nursing home resident in Mocksville, NC eating his favorite food macaroni TV dinner

35. 75YOWM nursing home resident in Mocksville, NC eating his favorite food macaroni TV dinner

36. 48yoWM from Fancy Gap, Virginia with syncopal episodes when using hands vigorously

37. Syncope - Diagnostic Strategy • ECG • yield for specific diagnosis low (5%) • risk free and relatively inexpensive. • abnormalities (BBB, previous MI, nonsustained VT) guide further evaluation • recommended in almost all patients

38. Syncope - Diagnostic Strategy • Hx and PE and EKG Diagnostic Suggestive Unexplained

39. Syncope - Diagnostic Strategy 50% 50% • Hx and PE and EKG Diagnostic Suggestive Unexplained

40. Syncope - Diagnostic Strategy • Hx and PE and EKG Diagnostic Suggestive Unexplained Laboratory Tests - Routine use not recommended - Should be done only if specifically suggested by H&P. - Pregnancy testing should be considered in women of child-bearing age, especially in those for whom tilt-table or EP testing is being considered.

41. Syncope - Diagnostic Strategy • Hx and PE and EKG Diagnostic Suggestive Unexplained Neurologic testing - EEG - not useful unless seizures - Brain imaging - not useful unless focality - Neurovascular studies - no studies - may be useful if bruits, or hx suggests vertebrobasilar insufficiency

42. Syncope - Diagnostic Strategy • Hx and PE and EKG Diagnostic Suggestive Unexplained Echocardiography - Recommended in patients when cardiac disease is suspected - Only makes the diagnosis in severe AS and atrial myxoma - Findings may be useful to stratify the risk of cardiac substrate

43. Syncope - Diagnostic Strategy • Hx and PE and EKG Diagnostic Suggestive Unexplained Examples vasovagal situational orthostatic hypotension polypharmacy in the elderly

44. Vasovagal Syncope • - most common cause of syncope - confusing terms (Bezold-Jarisch reflex, cardioinhibitory, neurocardiogenic, neurally mediated)- compensatory increase in sympathetic tone interrupted - mediated by excessive activation of cardiac mechanoreceptors that have connections to brainstem • - appropriate setting (fear, injury, illness, sight of blood, etc.)- upright posture- warning period of progressive symptoms (warmth, lightheadedness, nausea, roaring in ears, dimming vision)- prompt recovery (seconds) (beware of the well meaning bystander)

45. Vasovagal Syncope • Graham LA, Kenney RA. Clinical characteristics of patients with vasovagal reactions presenting as unexplained syncope. Europace 2001;3:141-46

46. Malignant Vasovagal Syncope • A 62-year-old man without significant medical history presented to his doctor with repeated episodes of syncope. The episodes were always associated with micturition (often at night) and had caused falls resulting in head injury. His wife was particularly concerned, noting that he became apneic while sleeping. He was diagnosed with sleep apnea. A 24-hour Holter monitor was obtained as part of the syncope evaluation. While wearing the monitor, he awoke in a panic, feeling that something was very wrong, and he came directly to the emergency room. He was evaluated in the emergency room and was told he was fine. The patient insisted, however, that the Holter monitor be reviewed before he left the hospital. The Holter monitor displayed 8 asystolic pauses, including 1 pause of 21 seconds and another of 35 seconds, at which point he awoke abruptly (Figure). The etiology was felt to be malignant vasovagal syncope. On the basis of these results, he was admitted to the hospital and a dual-chamber pacemaker was placed. At 18 months of follow-up, the patient reports no more episodes of micturition syncope. He uses the pacemaker only 2% of the time. He has greater energy, and his wife reports that the sleep apnea is gone.

47. Syncope - Diagnostic Strategy 50% • Hx and PE and EKG Diagnostic Suggestive Unexplained Examples vasovagal situational orthostatic hypotension polypharmacy in the elderly

48. Syncope - Diagnostic Strategy 50% • Hx and PE and EKG Diagnostic Suggestive Unexplained CNS disease EEG CCT, MRI Cerebral flow st. Angiography Carotid sinus syncope Carotid massage Reduced cardiac output Echocardiogram Cardiac cath CPK-MB, CCU admission Spiral CT scan Pulmonary arteriogram

49. Syncope - Diagnostic Strategy 50% • Hx and PE and EKG Diagnostic Suggestive Unexplained

50. Syncope - Diagnostic Strategy 50% • Hx and PE and EKG Diagnostic Suggestive Unexplained Organic heart disease or Abnormal EKG No suspected heart disease Age >60