1. Evaluation of Patients with Transient Ischemic Attack Rodney Smith, MD Clinical Assistant Professor Department of Emergency Medicine University of Michigan Ann Arbor, MI

2. Rodney Smith, MD Introduction A 55 year old male presents to the emergency department with acute onset of Left arm weakness: Unable to lift left arm off of lap Symptoms improved on the way to the hospital

3. Rodney Smith, MD Introduction PMHx: Hypertension Takes enalapril ROS: No headache No other neurologic symptoms Social Hx: Smokes 1 ppd

4. Rodney Smith, MD Introduction Physical Exam Overweight, in NAD 160/90, 80, 14, 37.5C Right carotid bruit Heart with regular rate and rhythm; No murmur

5. Rodney Smith, MD Introduction Neuro exam oriented to person, place, and time fluent speech CN II-XII intact motor 4/5 strength in left upper extremity sensory subjective decrease in pinprick in left upper extremity compared to the right DTR +2 except at left biceps +3 Gait steady cerebellar intact finger to finger and finger to nose no extensor plantar response.

6. Rodney Smith, MD Objectives What is a transient ischemic attack (TIA)? What is the differential diagnosis of patients with possible TIA? What is the ED approach to TIA? What is the treatment and disposition of patients with TIA?

7. Rodney Smith, MD Transient Ischemic Attack What is a TIA? Acute loss of focal cerebral function Symptoms last less than 24 hours Due to inadequate blood supply Thrombosis Embolism

8. Rodney Smith, MD Transient Ischemic Attack Acute loss of focal cerebral function Motor symptoms Weakness or clumsiness on one side Difficulty swallowing Speech disturbances Understanding or expressing spoken language Reading or writing Slurred speech Calculations

9. Rodney Smith, MD Transient Ischemic Attack Acute loss of focal cerebral function Sensory symptoms Altered feeling on one side Loss of vision on one side Loss of vision in left or right visual field Bilateral blindness Double vision Vertigo

10. Rodney Smith, MD Transient Ischemic Attack Non-focal Symptoms Generalized weakness or numbness Faintness or syncope Incontinence Isolated symptoms Vertigo or loss of balance Slurred speech or difficulty swallowing Double vision

11. Rodney Smith, MD Transient Ischemic Attack Non-focal Symptoms Confusion disorientation impaired attention/concentration diminution of all mental activity distinguish from isolated language, memory, or visual-spatial perception problems

12. Rodney Smith, MD

13. Transient Ischemic Attack Acute loss of focal cerebral function Abrupt onset Symptoms occur in all affected areas at the same time Symptoms resolve gradually Symptoms are “negative”

14. Rodney Smith, MD Transient Ischemic Attack Symptoms last less than 24 hours Most last less than one hour Less than 10 percent > 6 hours Amaurosis fugax up to five minutes Gradual resolution

15. Rodney Smith, MD Differential Diagnosis Migraine with aura Positive symptoms Spread over minutes Visual disturbances Somatosensory or motor disturbance Headache within 1 hour

16. Rodney Smith, MD Differential Diagnosis Aura without Headache Gradual onset with spread over minutes OR Positive visual symptoms Headache totally absent or mild No prior symptoms of classic migraine

17. Rodney Smith, MD Differential Diagnosis Aura without Headache 50 patients with case control TIA patients 10 year follow-up Mean age 48.7 (vs. 62.1) 60% male (vs. 68%) Fewer cardiovascular risk factors

18. Rodney Smith, MD Differential Diagnosis Aura without Headache 98% Visual symptoms 30% with other symptoms 26% sensory 16% aphasia 6% dysarthria 10% weakness

19. Rodney Smith, MD Differential Diagnosis Aura without HA Onset of symptoms in minutes Over 50% with onset over > 5 min.

20. Rodney Smith, MD Differential Diagnosis Aura without HA Duration of symptoms in minutes 20% with slight headache 20% with prior headaches without aura

21. Rodney Smith, MD Differential Diagnosis Partial (focal) seizure Positive sensory or motor symptoms Spread quickly (60 seconds) Negative symptoms afterward (Todd’s paresis) Multiple attacks

22. Rodney Smith, MD Differential Diagnosis Transient global amnesia Sudden disorder of memory (confusion) Antegrade and often retrograde Recurrence 3% per year Etiology unclear Migraine Epilepsy (7% within 1 year) Unknown

23. Rodney Smith, MD Differential Diagnosis Transient global amnesia No difference in vascular risk factors compared with general population Fewer risk factors when compared with TIA patients Prognosis significantly better than TIA

24. Rodney Smith, MD Differential Diagnosis Structural intracranial lesion Tumor Partial seizures Vascular steal Hemorrhage Vessel compression by tumor

25. Rodney Smith, MD Differential Diagnosis Intracranial hemorrhage ICH rare to confuse with TIA Subdural hematoma Headache Fluctuation of symptoms Mental status changes

26. Rodney Smith, MD Differential Diagnosis Multiple sclerosis Usually subacute but can be acute optic neuritis limb ataxia Age and risk factors Signs more pronounced than symptoms

27. Rodney Smith, MD Differential Diagnosis Labyrinthine disorders Central vs. Peripheral vertigo Ménière's disease Benign positional vertigo Acute vestibular neuronitis

28. Rodney Smith, MD Differential Diagnosis Metabolic Hypoglycemia Hyponatremia Hypercalcemia Peripheral nerve lesions Entrapments Painful quality

29. Rodney Smith, MD Likelihood of TIA

30. Rodney Smith, MD Likelihood of TIA Diagnosis of TIA Kraaijeveld, et al. 1984 56 patients evaluated by 2 of 8 “senior neurologists” Decide if TIA (yes or no) If yes, territory involved (carotid, vertebro-basilar, either, both) Is conclusion firm or doubtful?

31. Rodney Smith, MD Likelihood of TIA Clinical criteria Time course Symptoms of carotid TIA Symptoms of vertebro-basilar TIA Symptoms of uncertain territory Symptoms explicitly not TIA

32. Rodney Smith, MD Likelihood of TIA Agreement on 48 of 56 patients (85.7%) 36 with TIA 12 Not TIA 8 of 56 disagreement 4 of these, both listed firm diagnosis

33. Rodney Smith, MD Likelihood of TIA TIA yes or no kappa = 0.65 TIA circulation involved kappa = 0.31

34. Rodney Smith, MD Emergency Department Evaluation History Characteristics of the attack Associated symptoms Risk factors Vascular Disease Cardiac Disease Hematologic Disorders Smoking Prior TIA

35. Rodney Smith, MD Emergency Department Evaluation Physical Examination Neurologic Exam Carotid Bruits Cardiac Exam Peripheral Pulses

36. Rodney Smith, MD Emergency Department Evaluation EKG CBC, Coags, and Chemistries Chest Xray Head CT without contrast Expedite if early presentation

37. Rodney Smith, MD Decision Point Symptom vs. Disease Significant carotid artery stenosis Cardiac embolism Admission vs. Discharge Traditional approach Trend toward outpatient evaluation

38. Rodney Smith, MD Likelihood of Early Stroke Prognosis after TIA Dennis et al. Oxfordshire, UK 1981 - 1986 Prospective community-based study Incident TIA No history of prior stroke Whisnant, et al. Rochester, MN 1955 - 1969 Retrospective community-based study First-ever TIA

39. Rodney Smith, MD Likelihood of Early Stroke Stroke rate after TIA Annual rate during 5-year follow-up 6.7% Oxfordshire 6.6% Rochester, MN

40. Rodney Smith, MD Likelihood of Early Stroke Stroke Rate After TIA Percent (95% CI)

41. Rodney Smith, MD Carotid Endarterectomy and Stroke 70% stenosis or greater Best medical therapy vs. CEA

42. Rodney Smith, MD Carotid Endarterectomy and Stroke 50 - 69% stenosis Best medical therapy vs. CEA

43. Rodney Smith, MD Diagnosis of Carotid Stenosis

44. Rodney Smith, MD Diagnosis of Carotid Stenosis Carotid Duplex Ultrasound Sensitivity of 94 - 100% for > 50% stenosis May overdiagnose occlusion Non-invasive

45. Rodney Smith, MD Diagnosis of Carotid Stenosis Magnetic Resonance Angiography Similar sensitivity to carotid ultrasound Overestimates degree of stenosis Gives information about vertebrobasilar system Accuracy of 62% in detecting intracranial pathology Cost and claustrophobia

46. Rodney Smith, MD Diagnosis of Carotid Stenosis Cerebral Angiography Gold standard for diagnosis Invasive, with risk of stroke of up to 1% For patients with positive ultrasound For patients with occlusion on ultrasound First test if intracranial pathology suspected

47. Rodney Smith, MD Cardiogenic Embolism Major risk factors Atrial fibrillation Mitral stenosis Prosthetic cardiac valve Recent MI Thrombus in LV or LA appendage Atrial myxoma Infective endocarditis Dilated cardiomyopathy

48. Rodney Smith, MD Cardiogenic Embolism Minor risk factors Mitral valve prolapse Mitral annular calcification Patent foramen ovale Atrial septal aneurysm Calcific aortic stenosis LV regional wall motion abnormality Aortic arch atheromatous plaques Spontaneous echocardiographic contrast

49. Rodney Smith, MD Echocardiogram Yield < 3% in undifferentiated patients Higher with risk factors Indications Age < 50 Multiple TIAs in more than one arterial distribution Clinical, ECG, or CXR evidence suggests cardiac embolization

50. Rodney Smith, MD TIA Evaluation ED Disposition Admission Clear indication for anticoagulation Severe deficit Crescendo symptoms Other indication for admission

51. Rodney Smith, MD TIA Evaluation ED Disposition Discharge Further testing will not change treatment Prior workup Not a candidate for CEA or anticoagulation

52. Rodney Smith, MD Antiplatelet Therapy Aspirin Not dose dependent Ticlopidine Clopidogrel Aspirin plus Dipyridamole

53. Rodney Smith, MD Risk Factor Modulation Obesity Smoking Hypertension Cholesterol Excessive alcohol 1 to 2 glasses of wine per day may be protective