stroke; cerebrovascular accident (CVA)

Introduction

Cerebrovascular accident (CVA) or stroke is the rapid onset of a neurological deficit that persists for at least 24 hours.

Etiology

• strokes are caused by (15%) or subarachnoid hemorrhage (10%) or the
• see specific type of stroke
  • hemorrhagic stroke
    • intracerebral hemorrhage (15%)
    • subarachnoid hemorrhage (10%)
  • ischemic stroke (75%)
    • embolic stroke
    • also see risk factors for ischemic stroke
• cryptogenic stroke
  • cervical artery dissection
  • hypercoagulability
  • autoimmune disease
  • patent foramen ovale*
• shared risk factors (hemorrhagic stroke & ischemic stroke)
  • hypertension
  • cocaine abuse
  • tobacco abuse
  • malignancies
    • lung cancer (RR=4.2)
    • pancreatic cancer (RR=2.6)
    • colorectal cancer (RR=2.5)
    • breast cancer (RR=1.4)

* may be likely cause in younger patients; unlikely to cause subsequent stroke in the absence of hypercoagulability

Epidemiology

• 4% of individuals (mean age 75 years) will suffer from stroke within 4 years
• 7% of individuals ((baseline age 45-64 years)) will suffer stroke within 24 years
• no association with dietary fat
• incidence of stroke is declining, but severity is not
• worldwide, death from stroke is declining, but incidence is increasing
  • lower income countries account for the increase
  • incidence of stroke in high-income countries has declined
• worldwide, children & adults < 65 years of age account for 1/3 of strokes
• incidence of stroke worldwide will increase by 50% by 2050 if action is not taken to reduce risk factors

Pathology

• blockage of a blood vessel supplying or draining the brain (75%)

. elapsed time	changes
6 hrs.	no changes
8-48 hrs.	swelling
> 48 hrs.	soft, friable
2 weeks	liquefaction
> 3 weeks	cavitation (~1mL/3 months)

cell sensitivity to ischemia:

• neurons > oligodendrocytes > astrocytes > microglia > blood vessels

brain region sensitivity to ischemia:

• hippocampus (CA1) > extrapyramidal layer (3) of neocortex > cerebellar Purkinje cells > inferior olivary neurons > subthalamic nucleus

Microscopic pathology

Table

. elapsed time	changes
8 - 12 hrs.	classic ischemic changes*
12 - 48 hrs.	macrophages appear
48 hrs.	macrophages become foamy
3rd day	proliferating astrocytes, gemistocytes
7th day	capillary wall thickening
> 30 days	astrocytes only remaining (depends on size)

* classic ischemic changes: eosinophilic degeneration, glassy cytoplasm, loss of Nissl substance, hyperchromatic nuclei, neuronal shrinkage & increase in perineuronal space)

History

• onset, improvement or progression of symptoms, anatomic location of deficit, activity prior to onset, headache, nausea/vomiting, loss of consciousness, brisk neck movement, visual aura, scotoma, vertigo, seizure, trauma, confusion, dysarthria, incontinence, dysphagia, palpitations, prior TIAs or strokes, amaurosis fugax, HTN, diabetes, CAD, hyper- lipidemia, IVDA, cocaine, valvular heart disease, migraine, anticoagulants, oral contraceptives, tobacco, alcohol

Clinical manifestations

• focal or multifocal neurologic deficit evolving over second to minutes, persisting > 24 hours
  • carotid or vertebrobasilar artery territories
    • involvement of upper &/or lower extremity &/or face on opposite side, opposite visual field or eye onsame side
    • motor dysfunction:
      • dysarthria; weakness; clumsiness; pronator drift
    • sensory: numbness; paresthesias
    • blindness
      • monocular blindness (same side)
        • Hollenhorst plaque
      • homonymous hemianopia (opposite visual field)
  • carotid artery territory
    • paresthesias of hand, arm & face (contralateral)
    • hemiparesis more common with ischemic stroke
      • weakness of hand, arm & face (contralateral)
    • aphasia (dominant hemisphere)
    • dysarthria
    • unilateral neglect
    • loss of vision (ipsilateral eye)
    • carotid bruit
  • lacunar TIAs
    • hemibody sensory loss or paresthesias
    • pure motor hemiparesis
  • vertebrobasilar territory:
    • dysarthria
    • dysphagia
    • vertigo
    • ataxia
    • diplopia
    • visual field loss - homonymous hemianopia
    • perioral paresthesias
    • acute confusional state
    • profound general weakness
• nonfocal symptoms suggest increased intracranial pressure
  • common with:
    • hemorrhagic stroke
    • major ischemic stroke with cerebral edema
  • headache
  • nausea & vomiting
  • impaired consciousness
    • restlessness
    • drowsiness
    • coma
  • elevated systolic blood pressure

Laboratory

• all patients
  • serum glucose
  • electrolytes: serum K+ < 4.0 meq/L confers 2.5 fold increased risk of stroke in patients taking diuretics
  • serum creatinine, BUN
  • markers of myocardial infarction
  • complete blood count (CBC)
  • prothrombin time, INR, aPTT
• selected patients
  • liver function tests
  • toxicology screen
  • blood alcohol level
  • pregnancy test
  • arterial blood gas
• CSF analysis for xanthochromia if hemorrhagic stroke suspected

Diagnostic procedures

• all patients
  • electrocardiogram
  • pulse oximetry
• selected patients
  • echocardiography
  • cerebral angiography
    • determines localization & degree of carotid stenosis
    • necessary prior to carotid endarterectomy
    • identifies aneurysms & arteriovenous malformations (AVM)
  • lumbar puncture
    • CT negative for blood
    • subarachnoid hemorrhage suspected
    • CSF analysis for xanothochromia
• electroencephalography (EEG) if seizures suspected

Radiology

• all patients
  • computed tomography (CT) of head
    • obtained within 24 hours distinguishes hemorrhagic stroke from ischemic stroke
    • CT changes in ischemic stroke appear after 24 hours
  • MRI alternative to CT
    • can detect early ischemic strokes not seen by CT
    • can detect hemorrhagic strokes not seen on CT
    • proposed standard of care
    • not as fast as CT
    • patient in less monitored environment than CT
• selected patients
  • carotid artery ultrasound (Doppler)
  • chest X-ray (if lung disease suspected)

Complications

• anxiety (27-40%) develop clinically significant anxiety
• depression is common after stroke or TIA (14% at 1 year)
  • major depression with psychosis is a further complication
• cognitive impairment:
  • more common in hemorrhagic stroke than ischemic stroke
  • more common with left hemisphere stroke, cortical stroke
  • cognitive decline immediately after stroke & continued for at least 6-years thereafter
  • cognitive decline can occur both before & after a stroke
• delirium occurs in 12% of patients admitted to stroke unit; associated with poor prognosis
• residual focal neurologic deficits
• seizures early after stroke*
  • more common with hemorrhagic stroke than ischemic stroke (15% vs 4%)
  • more common with cortical stroke than subcortical stroke (19% vs 10%)
  • do not predict mortality or function at 6 months
• risk of pneumonia is highest in the 1st week after stroke
• PTSD in 25% of survivors within 1 year after stroke
• fatigue after stroke due to depression, sleep apnea, heart failure
• reemergence or recrudescence of stroke symptoms in the setting of an intercurrent illness
• stroke often compromises well-being of family caregivers
  • spouses of stroke survivors have reduced health-related quality-of-life many years after stroke
• 1/6 of patients will have another stroke within 5 years

* among anticonvulsants used as monotherapy in poststroke epilepsy, lamotrigine is associated with the lowest risk for mortality, valproate the highest

• disease interaction(s) of stroke with depression
• disease interaction(s) of stroke with urinary incontinence
• disease interaction(s) of stroke with ANCA-associated vasculitis
• disease interaction(s) of stroke with pneumonia
• disease interaction(s) of stroke with Alzheimer's disease

Differential diagnosis

• migraine headache (prodrome)
• head trauma - subdural hematoma
• seizure disorder with postictal hemiparesis
• arteritis
• multiple sclerosis (MS)
• central nervous system (CNS) infection
• intracranial mass lesion: brain tumor, brain abscess (evolution over hours to days)
• dementia (with subacute worsening of cognitive impairment)
• conversion disorder
• cardiac arrhythmia
• drug overdose
• hypertensive encephalopathy
• myasthenia gravis
• syncope
• systemic infection unmasking prior stroke-related deficit
• Bell's palsy
  • facial droop with dysarthria may suggest stroke
  • paralysis of the forehead muscles suggests Bell's palsy
  • most strokes that cause facial weakness have other neurologic signs, such as ipsilateral arm numbness or muscle weakness

Management

• see ACLS algorithm for suspected stroke
  • prehospital intravenous magnesium sulfate of no value
• NIH stroke scale recommended during emergency evaluation
• general
  • nothing by mouth (NPO) for the 1st 24 hours
  • provide supplemental oxygen
    • supplemental oxygen in patients with normal SaO2 increases mortality
  • control excessively high blood pressure
    • withhold antihypertensive treatment (2-7 days) if
      • systolic blood pressure < 220 mm Hg and
        • diastolic BP < 120 mm Hg
    • lower threshold (systolic blood pressure 180-200 mm Hg) recommended in patients with hemorrhagic stroke
      • target blood pressure is 160/90 mm Hg
    • initial goal is to lower systolic blood pressure by 25%
    • aggressive control of blood pressure not indicated except in:
      • myocardial infarction
      • hypertensive encephalopathy
    • labetolol nay be agent of choice
      • negligible effect on intracranial pressure
      • ARB not helpful
  • avoid hypotonic fluids (i.e. D5W) which may exacerbate cerebral edema
  • avoid glucose containing solutions in diabetic patients
  • serial neurologic examination
  • DVT prophylaxis
  • control of blood glucose; elevated blood glucose may induce increased intracranial pressure
  • mechanical ventilation as needed for severe stroke
    • early tracheostomy does not improve 6 month outcome
  • positioning, mobilization
    • avoid mobilization within 24 hours
      • of no benefit, possibly harmful
    • supine vs sitting up has no effect on disability or mortality after acute stroke
  • early physical therapy
  • dysphagia screening
    • clinically assess swallowing before initiating diet
    • beside swallowing evaluation with 97% sensitivity & -90% specificity for dysphagia
    • prophylactic antibiotics do not prevent pneumonia in post-stroke patients with dysphagia & may result in harm
  • patient education:
    • expectations
    • neurorehabilitation
• specific therapy under ischemic stroke & hemorrhagic stroke
• decompressive craniotomy or craniectomy for intracranial mass lesion effect
• stroke units (neurorehabilitation)
  • proposed standard of care
  • neurorehabilitation begins when the patient is medically stable
  • neurorehabilitation is provided in inpatient stroke units
  • in-home or nursing home rehabilitation is generally reserved for patients requiring a slower pace of neurorehabilitation
  • inpatient care in a stroke unit associated with diminished mortality 1 year after stroke
• telestroke systems of benefit for rural areas (see telehealth)
• cervical spinal cord stimulation for post-stroke upper extremity paresis investigational
• follow-up:
  • depression is common after stroke
    • treatment of depression can improve recovery
    • nortriptyline is superior to fluoxetine
    • citalopram & trazodone have been shown beneficial
    • antidepressants may improve survival in patients with or without depression
  • anxiety is common after stroke (27-40%)
    • depression & anxiety often coexist (74%)
    • treatment of anxiety may improve recovery
    • relaxation theraoy is standard
  • deconditioning in common
    • fatigue associated with lower extremity weakness
  • occupational therapy
    • routine occupational therapy of no benefit
  • exercise of no benefit in subacute phase after stroke
  • caregiver training
    • no benefit to training caregivers
  • risk factor modification*
    • hypertension: systolic BP < 140 mm Hg noninferior to < 120 mm Hg
    • smoking
    • diabetes
    • alcohol abuse
    • hypercholesterolemia
    • dietary K+ may reduce risk of stroke in patient NOT taking diuretics
  • ACE inhibitor may reduce risk*
    • combination of perindopril (Aceon) + indapamide (Lozol) found to reduced risk of recurrent stroke in patients with & without hypertension [7, 9]
    • ramipril >= 10 mg/day reduced stroke risk 31% & fatal stroke risk 61%, with BP reduction of 3.8/2.8 mm Hg
  • screening for osteoporosis with bone mineral density suggested
  • wait at least 9 months after ischemic stroke prior to elective non-cardiac surgery
  • horse-riding & music-&-rhythm therapies may help improve function & perceived recovery in patients years after a stroke
• prognosis
  • degree of long-term cognitive impairment after stroke cannot be determined for at least 3 months
  • some patients with transient ischemic attack & minor stroke become disabled within 3 months, even without having a recurrent vascular event
    • predictors of disability include:
      • baseline CT or CT angiography abnormalities
      • symptoms at presentation
      • female gender
      • diabetes mellitus
      • severity of initial neurologic deficit is the strongest predictor of long-term disability
  • ref discusses reduction in early mortality by aggressive management vs severe long-term disability
  • a first stroke relatively early in adulthood is associated with a higher mortality risk up to 20 years later *

* Follow-up

• neurorehabilitation

More general terms

• cerebrovascular disease/disorder

More specific terms

• brainstem infarction
• cerebellar infarction
• hemorrhagic stroke
• ischemic stroke
• silent brain infarct
• stroke, pre & postpartum (antenatal stroke)
• Weber-Gubler syndrome; hemiparesis alternans oculomotoria; superior alternating hemiplegia

Additional terms

• ACLS algorithm for suspected stroke
• hospice guidelines for determining prognosis, stroke & coma
• National Institutes of Health (NIH) Stroke Scale; (NIHSS score)
• neurorehabilitation
• reversible ischemic neurologic deficit (RIND)
• transient ischemic attack (TIA)

Patient information

stroke or cerebrovascular accident (CVA) patient information

Database

• OMIM: https://mirror.omim.org/entry/601367