Ischemic stroke

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Ischemic stroke causes (87% of all strokes)

  • Thrombotic (80% of ischemic CVA)
  • Embolic (20% of ischemic CVA)
    • Valvular vegetations
    • Mural thrombi
    • Arterial-arterial emboli from proximal source
    • Fat emboli
    • Septic emboli
  • Hypoperfusion
    • Cardiac failure resulting in systemic hypotension

Clinical Features

Anterior Circulation

  • Blood supply via internal carotid system
  • Includes ACA and MCA

Internal Carotid Artery

  • Tonic gaze deviation towards lesion
  • Global aphasia, dysgraphia, dyslexia, dyscalculia, disorientation (dominant lesion)
  • Spatial or visual neglect (non-dominant lesion)

Anterior Cerebral Artery (ACA)

Signs and Symptoms:

  • Contralateral sensory and motor symptoms in the lower extremity (sparing hands/face)
  • Urinary incontinence
  • Left sided lesion: akinetic mutism, transcortical motor aphasia
  • Right sided lesion: Confusion, motor hemineglect

Middle Cerebral Artery (MCA)

Signs and Symptoms:

  • Hemiparesis, facial plegia, sensory loss contralateral to affected cortex
  • Motor deficits found more commonly in face and upper extremity than lower extremity
  • Dominant hemisphere involved: aphasia
  • Nondominant hemisphere involved: dysarthria w/o aphasia, inattention and neglect side opposite to infarct
  • Contralateral homonymous hemianopsia
  • Gaze preference toward side of infarct

Posterior circulation

Signs and Symptoms:

  • Crossed neuro deficits (i.e., ipsilateral CN deficits w/ contralateral motor weakness)
  • Multiple, simultaneous complaints are the rule
  • 5 Ds: Dizziness (Vertigo), Dysarthria, Dystaxia, Diplopia, Dysphagia
  • Isolated events are not attributable to vertebral occlusive disease (e.g. isolated lightheadedness, vertigo, transient ALOC, drop attacks)

Basilar artery

Signs and Symptoms:

  • Quadriplegia, coma, locked-in syndrome
  • Sparing of vertical eye movements (CN III exits brainstem just above lesion)
    • Thus, may also have miosis b/l
  • One and a half syndrome (seen in a variety of brainstem infarctions)
    • "Half" - INO (internuclear opthalmoplegia) in one direction
    • "One" - inability for conjugate gaze in other direction
    • Convergence and vertical EOM intact
  • Medial inferior pontine syndrome (paramedian basilar artery branch)
    • Ipsilateral conjugate gaze towards lesion (PPRF), nystagmus (CN VIII), ataxia, diplopia on lateral gaze (CN VI)
    • Contralateral face/arm/leg paralysis and decreased proprioception
  • Medial midpontine syndrome (paramedian midbasilar artery branch)
    • Ipsilateral ataxia
    • Contralateral face/arm/leg paralysis and decreased proprioception
  • Medial superior pontine syndrome (paramedian upper basilar artery branches)
    • Ipsilateral ataxia, INO, myoclonus of pharynx/vocal cords/face
    • Contralateral face/arm/leg paralysis and decreased proprioception

Superior Cerebellar Artery (SCA)

  • ~2% of all cerebral infarctions[1]
  • May present with nonspecific symptoms - N/V, dizziness, ataxia, nystagmus (more commonly horizontal)[2]
  • Lateral superior pontine syndrome
    • Ipsilateral ataxia, n/v, nystagmus, Horner's syndrome, conjugate gaze paresis
    • Contralateral loss of pain/temperature in face/extremities/trunk, and loss of proprioception/vibration in LE > UE

Posterior Cerebral Artery (PCA)

Signs and Symptoms:

  • Common after CPR, as occiptal cortex is a watershed area
  • Unilateral headache (most common presenting complaint)
  • Visual field defects (contralateral homonymous hemianopsia, unilateral blindness)
  • Visual agnosia - can't recognize objects
  • Possible macular sparing if MCA unaffected
  • Motor function is typically minimally affected
  • Lateral midbrain syndrome (penetrating arteries from PCA)
    • Ipsilateral CN III - eye down and out, pupil dilated
    • Contralateral hemiataxia, tremor, hyperkinesis (red nucleus)
  • Medial midbrain syndrome (upper basilar and proximal PCA)
    • Ipsilateral CN III - eye down and out, pupil dilated
    • Contralateral paralysis of face, arm, leg (corticospinal)

Anterior Inferior Cerebellar Artery (AICA)

  • Lateral inferior pontine syndrome
  • Ipsilateral facial paralysis, loss of corneal reflex (CN VII)
  • Ipsilateral loss of pain/temp (CN V)
  • Nystagmus, N/V, vertigo, ipsilateral hearing loss (CN VIII)
  • Ipsilateral limb and gait ataxia
  • Ipsilateral Horner syndrome
  • Contralateral loss of pain/temp in trunk and extremities (lateral spinothalamic)

Posterior Inferior Cerebellar Artery (PICA)

Signs and Symptoms:

  • Lateral medullary/Wallenberg syndrome
  • Ipsilateral cerebellar signs, ipsilateral loss of pain/temp of face, ipsilateral Horner's syndrome, ipsilateral dysphagia and hoarseness, dysarthria, vertigo/nystagmus
  • Contralateral loss of pain/temp over body
  • Also caused by vertebral artery occlusion (most cases)

Internal Capsule and Lacunar Infarcts

  • May present with either lacunar c/l pure motor or c/l pure sensory (of face and body)[3]
    • Pure c/l motor - posterior limb of internal capsule infarct
    • Pure c/l sensory - thalamic infarct (Dejerine and Roussy syndrome)
  • C/l motor plus sensory if large enough
  • Clinically to cortical large ACA + MCA stroke - the following signs suggest cortical rather than internal capsule[4]:
    • Gaze preference
    • Visual field defects
    • Aphasia (dominant lesion, MCA)
    • Spatial neglect (non-dominant lesion)
  • Others
    • I/l ataxic hemiparesis, with legs worse than arms - posterior limb of internal capsule infarct

Anterior Spinal Artery (ASA)

Superior ASA

  • Medial medullary syndrome - displays alternating pattern of sidedness of symptoms below
  • Contralateral arm/leg weakness and proprioception/vibration
  • Tongue deviation towards lesion

Inferior ASA

  • ASA syndrome
  • Watershed area of hypoperfusion in T4-T8
  • B/l pain/temp loss in trunk and extremities (spinothalamic)
  • B/l weakness in trunk and extremities (corticospinal)
  • Preservation of dorsal columns

Differential Diagnosis

Stroke-like Symptoms


Stroke Work-Up

  • Labs
    • POC glucose
    • CBC
    • Chemistry
    • Coags
    • Troponin
    • T&S
  • ECG
    • In large ICH or stroke, may see deep TWI and prolong QT, occ ST changes
  • Head CT (non-contrast)
    • In ischemia stroke CT has sensitivity 42%, specificity 91%[5]
    • In acute ICH the sensitivity is 95-100%[6]
    • The goal of CTH is to identify stroke mimics (ICH, mass lesions, etc .)[7]
  • Also consider:
    • CTA brain and neck (to check for large vessel occlusion for potential thrombectomy)
    • Pregnancy test
    • CXR (if infection suspected)
    • UA (if infection suspected)
    • Utox (if ingestion suspected)

MR Imaging (for Rule-Out CVA or TIA)

  • MRI Brain with DWI (without contrast) AND
  • Cervical vascular imaging (ACEP Level B in patients with high short-term risk for stroke):[8]
    • MRA brain (without contrast) AND
    • MRA neck (without contrast)
      • May instead use Carotid CTA or US (Carotid US slightly less sensitive than MRA)[9] (ACEP Level C)


To differentiate between tPA and non-tPA candidates see Thrombolysis in Acute Ischemic Stroke (tPA)

Both tPA AND non-tPA candidates

  • Prevent dehydration
  • Maintain SpO2 >92%
  • Maintain blood glucose between 140 and 180mg/dL
  • Prevent fever
  • HOB >30°

tPA Candidate

  • tPA
  • Hypertension
    • Lower SBP to <185, DBP to <110
    • Options:
      • Labetalol 10–20mg IV over 1–2 min; may repeat x1 OR
      • Nitroglycerin paste, 1–2 in. to skin OR
      • Nicardipine 5mg/hr, titrate up by 2.5mg/hr at 5-15min intervals; max dose 15mg/hr
        • When desired blood pressure attained reduce to 3mg/hr

Non-tPA Candidate

  • Hypertension
    • Allow permissive hypertension
    • If SBP >220 or DBP >120, lower by 25% over 24 hrs (drug of choice is Nicardipine)[10]
  • Aspirin 325mg (within 24-48hr)
  • Anticoagulation not recommended for acute stroke (even for A-fib)

Endovascular Therapy

  • Mechanical clot removal for large vessel occlusions (e.g. M1 occlusion, basilar artery occlusion)
  • Early trials MR RESCUE, SYNTHESIS, and IMSIII showed no benefit and potential harm
  • MR CLEAN Trial show promising outcomes[11]
    • Participants had proximal intracranial artery occlusions
    • Intervention was conducted within 6 hrs
    • Functional independence of 32.6% with endovascular treatment and 19.1% with typical therapy
  • Institutional dependent time window for intervention
  • May require careful patient selection based on last known normal and additional diagnostic studies such as CT perfusion study, Rapid MRI, etc


  • Early neurosurgical consultation is needed (herniation may lead to rapid deterioration)
  • See Cerebellar Stroke


  • Cochrane review showed no benefit in mortality or functional outcomes[12]


  • Admit all acute and subacute ischemic strokes

See Also

External Links


  1. Macdonell RA, Kalnins RM, Donnan GA. Cerebellar infarction: natural history, prognosis, and pathology. Stroke. 18 (5): 849-55.
  2. Lee H, Kim HA. Nystagmus in SCA territory cerebellar infarction: pattern and a possible mechanism. J Neurol Neurosurg Psychiatry. 2013 Apr;84(4):446-51.
  3. Rezaee A and Jones J et al. Lacunar stroke syndrome. Radiopaedia.
  4. Internal Capsule Stroke. Stanford Medicine Guide.
  5. Mullins ME, Schaefer PW, Sorensen AG, Halpern EF, Ay H, He J, Koroshetz WJ, Gonzalez RG. CT and conventional and diffusion-weighted MR imaging in acute stroke: study in 691 patients at presentation to the emergency department. Radiology. 2002 Aug;224(2):353-60.
  6. Suarez JI, Tarr RW, Selman WR. Aneurysmal subarachnoid hemorrhage. N Engl J Med. 2006; 354(4):387–396.
  7. Douglas VC, Johnston CM, Elkins J, et al. Head computed tomography findings predict short-term stroke risk after transient ischemic attack. Stroke. 2003;34:2894-2899.
  8. ACEP Clinical Policy: Suspected Transient Ischemic Attackfull text
  9. Nederkoorn PJ, Mali WP, Eikelboom BC, et al. Preoperative diagnosis of carotid artery stenosis. Accuracy of noninvasive testing. Stroke. 2002;33:2003-2008.
  10. Zha AM, et al. Recommendations for management of large hemispheric infarction. Curr Opin Crit Care. 2015; 21(2):91-8.
  11. Berkhemer OA, et al. A randomized trial of intraarterial treatment for acute ischemic stroke. NEJM. 2015; 372(1):11-20.
  12. Sandercock PA and Soane T. Corticosteroids for acute ischaemic stroke. Cochrane Database Syst Rev. 2011 Sep 7;(9):CD000064.