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Source: Fagan SC, Hess DC. Chapter 27. Stroke. In: DiPiro JT, Talbert RL, Yee GC, Matzke GR, Wells BG,
Posey LM, eds. Pharmacotherapy: A Pathophysiologic
Approach. 8th ed. http://accesspharmacy.com/content.aspx?aid=7973981.
Accessed June 27, 2012.
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- Apoplexy
- Cerebrovascular accident (CVA)
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- Interruption of blood flow to area of brain, causing death
of brain cells in area.
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- Local thrombus formation (e.g., cerebral atherosclerosis)
- Emboli from intra- or extracranial arteries that occlude cerebral
artery
- Unknown causes
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- Carotid atherosclerosis: Ruptured plaques lead to thrombus
formation that may cause local occlusion or dislodge and travel
distally, eventually occluding cerebral vessel.
- Cardiogenic embolism: Stasis of blood flow in atria or ventricles
leads to formation of clots that dislodge and travel through aorta
to cerebral circulation.
- Resulting arterial occlusion decreases cerebral blood flow
and causes ischemia and infarction distal to occlusion.
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- Stroke (including ischemic and hemorrhagic types) leading
cause of adult disability in United States.
- African Americans have stroke rates twice
those of whites.
- Some states in southeastern United States have stroke mortality
rates more than twice national average.
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- Preventive measures directed toward reducing or eliminating
modifiable risk factors for stroke.
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- Nonmodifiable risk factors:
- Increased
age
- Male sex
- Race (African Americans, Asian–Pacific Islanders,
Hispanics)
- Family history of stroke
- Low birth weight
- Major modifiable risk factors:
- Hypertension
- Cardiac disease (especially atrial fibrillation)
- Other risk factors:
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- May need to obtain medical history from family members
or others because cognitive or language deficits may preclude patient
from giving reliable history.
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- Symptoms:
- Weakness on one side of body
- Inability to speak
- Loss of vision
- Vertigo
- Falling
- Headache
- Signs of neurologic dysfunction depend on brain area involved.
- Hemi- or monoparesis and hemisensory deficits common.
- Posterior circulation involvement may present with vertigo
and diplopia.
- Anterior circulation strokes result in aphasia.
- Other potential signs:
- Dysarthria
- Visual field defects
- Altered levels of consciousness may be present.
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- Obtain tests for hypercoagulable states (protein C, protein
S, antithrombin III) only when cause cannot be determined based
on review of risk factors.
- Obtain antiphospholipid antibodies in patients younger than
age 50 and those who have had multiple thrombotic events or livedo
reticularis.
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- Computed tomography (CT) head scan
- Magnetic resonance imaging (MRI) of head reveals ischemic
areas with higher resolution and earlier than CT scan.
- Carotid Doppler (CD) studies can identify degree of stenosis
in carotid arteries.
- Transthoracic echocardiogram (TTE) can detect valve or wall
motion abnormalities that are sources of emboli.
- Transesophageal echocardiogram (TEE) more sensitive for left
atrial thrombus.
- Transcranial Doppler (TCD) can determine presence of intracranial
sclerosis (e.g., middle cerebral artery stenosis).
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Diagnostic Procedures
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- Electrocardiogram (ECG) will determine whether atrial
fibrillation is possible cause.
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Differential
Diagnosis
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- Hypoglycemia
- Transient ischemic attack
- Intracerebral hemorrhage or other mass lesion (e.g., tumor)
- Focal seizure
- Migraine
- Peripheral causes of vertigo (Meniere’s disease)
...