Section 1: Stroke and Transient Ischemic Attack (TIA) Flashcards
Common presentations of Strokes and TIAs?
Sudden onset of weakness of one side of the body
- Weakness of one half of the face and aphasia are common
- There may be partial or total loss of vision
Difference between stroke and TIA
Stroke lasts more than 24 hours; TIA lasts <= 24 hours
Transient loss of vision in one eye (from TIA)
Amaurosis Fugax
A 67-year-old man with a history of hypertension and diabetes comes to the emergency department with a sudden onset of weakness in the right arm and leg over the last hour. On exam, he cannot lift the bottom half of the right side of his face. What is the best initial step?
a. Head CT with contrast
b. Head CT without contrast
c. Aspirin
d. Thrombolytics
e. MRI
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 6771-6784). . Kindle Edition.
B. Prior to administering thrombolytics or any anticoagulation, you need to rule out hemorrhagic stroke, which is a contraindication to thrombolytics. You cannot even give aspirin without doing a head CT first. Thrombolytics are indicated within the first 3 hours of the onset of the symptoms of a stroke. Remember, 20 percent of strokes are hemorrhagic. You do not need contrast to visualize blood; contrast is used to detect cancer or infection, such as an abscess.
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 6771-6784). . Kindle Edition.
List the features of a stroke involving the anterior cerebral artery
- Profound lower extremity weakness (contralateral in the case of unilateral arterial occlusion)
- Mild upper extremity weakness (contralateral in the case of unilateral arterial occlusion)
- Personality changes or psychiatric disturbance
- Urinary incontinence
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 6790-6812). . Kindle Edition.
List the features of a stroke involving the middle cerebral artery
- Profound upper extremity weakness (contralateral in the case of unilateral arterial occlusion)
- Aphasia
- Apraxia/ neglect
- The eyes deviate toward the side of the lesion
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 6790-6812). . Kindle Edition.
List the features of stroke involving the posterior cerebral artery
- Contralateral homonymous hemianopia, with macular sparing
- Prosopagnosia (inability to recognize faces)
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Location 6807). . Kindle Edition.
List the features of stroke involving the vertebrobasilar artery
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 6808-6833). . Kindle Edition.
- Vertigo
- Nausea and vomiting
- May be described as a “drop attack”
- Vertical nystagmus
- Dysarthria and dystonia
- Sensory changes in face and scalp
- Ataxia
- Labile blood pressure
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 6808-6833). . Kindle Edition.
List the features of stroke involving the posterior inferior cerebellar artery
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 6808-6833). . Kindle Edition.
- Ipsilateral face
- Contralateral body
- Vertigo and Horner’s syndrome
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 6808-6833). . Kindle Edition.
List the features of stroke involving the lacunar infarct
- There must be an absence of cortical deficits
- Ataxia
- Parkinsonian signs
- Sensory deficits
- Hemiparesis (most notable in the face)
- Possible bulbar signs
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 6808-6833). . Kindle Edition.
List the feature(s) of stroke involving the ophthalmic artery
Amaurosis fugax
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 6808-6833). . Kindle Edition.
Diagnostic tests for stroke and TIA
Best initial test
CT Scan of Head without contrast
MRI
MRA
Rx of stroke
- Thrombolytics if patient present within 3 hours of stroke symptoms
- Anti-platelet medication: Aspirin or clopidogrel or aspirin combined with dipyridamole is acceptable as initial antiplatelet medication to prevent a subsequent stroke. However, at the present time, aspirin first is still the standard of care.
- Aspirin: Best initial therapy for those coming too late for thrombolytics. Also indicated after the use of thrombolytics.
- Clopidogrel: Switch to clopidogrel if the patient has developed a stroke on aspirin.
- Dipyridamole: If the patient is already on aspirin when a new stroke or TIA occurs, add dipyridamole or switch to clopidogrel.
- Heparin: There is no clear evidence of heparin’s benefit for stroke.
- Ticlopidine is always a wrong answer. It has no added benefit to the use of clopidogrel and has more adverse effects, such as TTP and neutropenia. Ticlopidine is used in those who are intolerant of both aspirin and clopidogrel.
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 6871-6873). . Kindle Edition.
Stroke Management
- Most important thing to do first
- After initial Rx, what is the most important thing to do?
- Other important tests to do in stroke or TIA
- Important tests for stroke patients less than 50 years
- CT of head without contrast; thrombolytics (if applicable) and aspirin
- Determine the origin of the stroke
- Echocardiogram; Carotid dopplers/duplex; EKG or Holter monitor
- ESR; VDRL or RPR; ANA, double-stranded DNA; Protein C, protein S, factor V Leiden mutation, antiphospholipid syndromes; Rx HTN, DM and hyperlipidemia
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 6885-6887). . Kindle Edition.
True or False:
- Anterior stroke and middle cerebral artery stroke are managed the same way.
- The younger the patient, the more likely the cause of the stroke is a vasculitis or hypercoagulable state.
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 6891-6893). . Kindle Edition.
- True
- True
