Clinical Presentation of Cerebrovascular Disease

1. Clinical Presentation of Cerebrovascular Disease David Griesemer, MD Department of Neurosciences Medical University of South Carolina

2. Presentation Outline • Stroke from the patient’s perspective • Definition of transient ischemic attacks • “Classic” presentations of stroke types • Focus on lacunar strokes • Prevention pearls • Diagnostic pitfalls

3. The Patient Perspective

4. Stroke Statistics • 15% of adults > age 50 cannot name a single symptom of stroke • 13 hours after onset of symptoms is the median time to presentation • 58% of stroke patients don’t present during the first 24 hours after onset • 52% of stroke patients in the ED are unaware that they are experiencing a stroke

5. MYTHS Can’t prevent stroke Can’t treat stroke Stroke affects the heart Stroke affects the elderly Recovery happens for a few months after stroke FACTS Stroke is preventable Stroke is treatable Stroke is a brain attack Stroke affects anyone Stroke recovery occurs throughout life Stroke Knowledge

6. Stroke Symptoms • Sudden numbness or weakness of face, arm or leg, especially on one side of the body • Sudden confusion, trouble understanding or speaking • Sudden trouble seeing in one or both eyes • Sudden trouble walking, dizziness, loss of balance or coordination • Sudden severe headache with no known cause

7. Other Symptoms • Sudden nausea, fever and vomiting, distinguished from a viral illness by rapid onset (minutes or hours vs. days) • Brief loss of consciousness or period of decreased consciousness (fainting, confusion, convulsions or coma)

8. The Three R’s for Brain Attack • Reduce risk • Recognize symptoms • Respond by calling 911

9. TIA: The First Clue

10. Transient Ischemic Attack • “Sudden, focal neurologic deficit lasting less than 24 hours, confined to an area of the brain or eye perfused by a specific artery.” • Based on assumption that TIAs do not cause infarction or other permanent brain injury. • Time criterion is arbitrary.

11. Problems with TIA Definition • Most TIAs last seconds to 10 minutes, with symptoms lasting greater than 1 hour in only 25% of patients • Less than 15% of patients with symptoms lasting > 1 hour resolve within 24 hours • Following TIAs, evidence of infarction is found in 20% by CT imaging and almost 50% with MRI • The “24-hour” rule leads to complacency and delay.

12. Tissue Definition of TIA • “A TIA is a brief episode of neurologic dysfunction caused by focal brain or retinal ischemia, with clinical symptoms typically lasting less than one hour, and without evidence of acute infarction.” • Parallel to distinction between angina and myocardial infarction (i.e. depends on the absence of tissue injury rather than the resolution of symptoms)

13. Advantages • Acknowledges that transient neurologic symptoms may cause permanent brain injury • Supports rapid intervention to diagnose and treat acute brain ischemia • More accurately reflects the presence or absence of brain infarction • Avoids assigning an arbitrary time criterion to define TIA

14. Anxiety (panic attack) Hyperventilation Neuropathy (focal) Neuropathy (ischemic) Vertigo Disequilibrium Migraine Orthostatic hypotension Syncope Arrhythmias (ischemia) Seizures Conversion disorder TIA - Differential Diagnosis

15. TIA v. Dizziness • Isolated symptom unlikely to be ischemic (true also for blurred vision or diplopia) • Evidence of brainstem dysfunction • Ataxia or nystagmus • Cranial nerve abnormality • Contralateral corticospinal tract abnormality

16. TIA v. Migraine • Onset in middle age • Aura without headache • Dysfunction in periaqueductal gray region of brainstem, not vascular • Progressive visual scintillation affecting both eyes • Stereotypic episodes or positive family history, especially with familial hemiplegic migraine

17. Stroke: The Initial Symptoms

18. Clinical Presentations of Stroke • Focal ischemia (85%) • Embolism • Thrombosis • Hemorrhage (15%) • Epidural • Subdural • Intraparenchymal

19. Embolism Abrupt onset Small vascular area Focal deficit Pure aphasia Pure hemianopia Acute CT normal High recurrence risk Thrombosis Preceded by TIAs Abrupt onset Large vascular area More complex symptoms Acute CT normal Cerebral Ischemia

20. Epidural hemorrhage Smooth onset Arterial origin Mass effect causes coma over hours Similar (but slower in evolution) to hemorrhage in basal ganglia Subdural hemorrhage Smooth onset Venous origin May be recurrent Fluctuating, falsely localizing signs Cerebral Hemorrhage

21. Remember Lacunar Strokes

22. Lacunar Strokes • 15 – 20% of ischemic strokes • Small penetrating branches of circle of Willis, MCA, or vertebrobasilar artery • Atherothrombotic or lipohyalinotic occlusion • Infarct of deep brain structures • Basal ganglia, cerebral white matter, thalamus, pons, and cerebellum • From 3 mm to 2 cm

23. Presentation of Lacunar Stroke • Risk factors • Diabetes • Hypertension • Polycythemia • Variable course progressing over days • Fluctuating; progressing in steps; or remitting • Preceded by TIAs in 25% • Without headache or vomiting

24. Lacunar Stroke Syndromes • Well-defined syndromes • Pure motor hemiparesis (with dysarthria) • Pure sensory stroke (loss or paresthesias) • Dysarthria-clumsy hand (with contralateral face and tongue weakness) • Ataxia-hemiparesis (contralateral face and leg weakness) • Isolated motor-sensory stroke

25. Lacunar Stroke Outcome • Management • Long-term blood pressure control • Empiric anti-platelet therapy • Omega-3 oil 1 gm TID to improve viscosity • Prognosis • Good recovery of function • Other lacunes develop

26. Prevention Pearls

27. Reducing Primary Risk - 1 • Obstructive sleep apnea • Homocysteine  folate, B6, B12 • Hypertension – morning BP surge • Smoking  50% risk reduction in 1 yr • Hyperlipidemia  statins • Migraine  triptans • Drugs – cocaine, ephedra, PPA

28. Reducing Primary Risk - 2 • Asymptomatic carotid stenosis • Endarterectomy for > 60% stenosis • Risk reduction for 3% to 1% per year • Benefit related to surgical risk • Nonvalvular atrial fibrillation • Aspirin for patients < 65 years, healthy • Warfarin for patients > 65 years or having other stroke risk factors

29. Reducing Secondary Risk Reducing risk of recurrence • TIA with ipsilateral carotid stenosis  endarterectomy for > 70% stenosis • Cardiogenic embolism  warfarin • Lacunar infarcts  aspirin, dipyridamole • Cryptogenic infarcts (40% embolic)  anticoagulation?

30. Reducing Risk in Children • Sickle cell disease • Screen with transcranial doppler q 6 mo • Transfusion therapy for 2 abnormal studies • Congenital heart disease • Arterial dissections (trauma) • Prothrombotic disorders • Mitochondria disorders (MELAS)

31. Medical Evidence www.jr2.ox.ac.uk/bandolier/knowledge.html

32. Decreasing Salt Intake • Reducing salt intake by 3 g per day lowers blood pressure; the effect is doubled with a 6 gm/day reduction and tripled with a 9 gm/d reduction. • Reduction in stroke risk parallels reduction in salt intake.

33. Using Statins • Pooled results after 5 years • Pravastatin or Simvastatin 40 mg/day • Changes in cholesterol levels • Total cholesterol decreased 20% • LDL cholesterol decreased 28% • HDL cholesterol increased 5% • Triglycerides decreased 13%

34. Using Statins • Reducing LDL cholesterol by 1 mmol/L • 22% stroke reduction in patients with known vascular disease • 6% stroke reduction in patients without known vascular disease • 28% reduction in thromboembolic stroke

35. Diagnostic Pitfalls

36. Practical Guidance Goldszmidt and Caplan, Stroke Essentials, Physicians’ Press, 2003 www.physicianspress.com

37. Pitfall #1 Basing treatment on brain imaging alone without a vascular work-up. A left frontal stroke caused by tight carotid stenosis requires revascularization, but the same stroke caused by atrial fibrillation requires warfarin.

38. Pitfall #2 Basing work-up and treatment on the temporal course of stroke. Intervention should focus on the vascular lesion. In fact, the same vascular lesion could cause TIA, evolving stroke, or completed stroke.

39. Pitfall #3 Overlooking a mimic of TIA or stroke. • 19% of patients diagnosed with stroke in ED have an imitator of stroke • Common confounders • Seizures • Systemic infection • Brain tumor • Toxic-metabolic encephalopathy

40. Pitfall #4 Mistaking the time of symptom onset for patients who wake up with stroke. Strokes are painless and do not wake people up. Because of risk of late thrombolysis, onset time should be assumed to be when they were last awake. Diffusion-weighted MRI may be helpful in determining benefit/risk of thrombolytic therapy.

41. Pitfall #5 Failing to investigate intracranial as well as extracranial circulations. Emboli or thrombi can come from anywhere in the carotid or vertebrobasilar. Carotid duplex imaging does not investigate the intracranial circulation. Transcranial doppler or MRA can non-invasively detect intracranial lesions,l more common in African-American and Asian patients.

42. Pitfall #6 Failing to distinguish severe carotid stenosis from total occlusion. Severe stenosis may require urgent surgery; total occlusion usually requires medical therapy. Neither carotid duplex imaging nor MRA can fully distinguish between the two. Conventional angiography is the test of choice.

43. Pitfall #7 Failing to check spinal fluid in patients with suspected subarachnoid hemorrhage. CT has 90% sensitivity for subarachnoid blood on day of onset, but sensitivity decreases over time. Also, small hemorrhages can be missed. For patients with suspected SAH who have a negative CT, lumbar puncture is needed.

44. Pitfall #8 Considering only embolism in stroke patients with atrial fibrillation. More than 25% of ischemic strokes in patients with AF have causes other than cardiogenic embolism (e.g. aortic arch atheroma and intrinsic vascular disease). Other interventions, such as carotid revascularization, may be required.

45. Pitfall #9 Overtreating hypertension in acute stroke. Because autoregulation is lost in ischemic brain, aggressive lowering of BP may cause infarct extension. Treat BP > 200/120 in absence of thrombolytics or > 180/115 with thrombolytics

46. Pitfall #10 Failing to adequate evaluate the heart. Silent myocardial infarction and arrhythmias are common complications of stroke. MI occurs in 20% of patients with acute stroke. It is a common cause of death at 1 – 4 weeks.