Ischemic stroke

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Sensory Homonculus - courtesy

Ischemic stroke causes (87%)

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 and bowel incontinence
  • Left sided lesion: akinetic mutism, transcortical motor aphasia
  • Right sided lesion: Confusion, motor hemineglect
  • Presence of primitive grasp and suck reflexes
  • May manifest gait apraxia

Middle Cerebral Artery (MCA)

Patient with stroke (forehead sparing).

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
    • Wernicke's aphasia (receptive aphasia) -> patient unable to process sensory input and does not understand verbal communication
    • Broca's aphasia (expressive aphasia) -> patient unable to communicate verbally, even though understanding may be intact
  • Nondominant hemisphere involved: dysarthria (motor deficit of the mouth and speech muscles; understanding intact) w/o aphasia, inattention and neglect side opposite to infarct
  • Contralateral homonymous hemianopsia
  • Gaze preference toward side of infarct
  • Agnosia (inability to recognize previously known subjects)

Posterior circulation

Signs and Symptoms:

Basilar artery

Signs and Symptoms:

  • Quadriplegia, coma, locked-in syndrome
  • "Crossed signs" in which a patient has unilateral cranial nerve deficits but contralateral hemiparesis and hemisensory loss suggest brainstem infarction
    • Millard-Gubler syndrome (ventral pontine syndrome) -- ipsilateral CN VI and VII palsy with contralateral hemiplegia of extremities
  • 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 ophthalmoplegia) 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)

Posterior Cerebral Artery (PCA)

Signs and Symptoms:

  • Common after CPR, as occipital 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)

Posterior Inferior Cerebellar Artery (PICA)

Signs and Symptoms:

  • Lateral medullary/Wallenberg syndrome
  • Ipsilateral cerebellar signs, ipsilateral loss of pain/temperature of face, ipsilateral Horner 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)[4]
    • 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[5]:
    • Gaze preference
    • Visual field defects
    • Aphasia (dominant lesion, MCA)
    • Spatial neglect (non-dominant lesion)
  • Others
    • Ipsilateral ataxic hemiparesis, with legs worse than arms - posterior limb of internal capsule infarct
    • Dysarthria/Clumsy Hand Syndrome - basilar pons or anterior 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
  • Bilateral pain/temp loss in trunk and extremities (spinothalamic)
  • Bilateral weakness in trunk and extremities (corticospinal)
  • Preservation of dorsal columns

Differential Diagnosis

Stroke-like Symptoms


A CT showing early signs of a middle cerebral artery stroke with loss of definition of the gyri and grey white boundary
12-lead ECG of a patient with acute stroke, showing large deeply inverted T-waves.

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%[6]
    • In acute ICH the sensitivity is 95-100%[7]
    • The goal of CTH is to identify stroke mimics (ICH, mass lesions, etc .)[8]
  • Also consider:
    • CTA brain and neck
      • To check for large vessel occlusion for potential thrombectomy
      • Determine if there is carotid stenosis that warrants endarterectomy urgently
    • 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, ADC (without contrast) AND
  • Cervical vascular imaging (ACEP Level B in patients with high short-term risk for stroke):[9]
    • MRA brain (without contrast) AND
    • MRA neck (without contrast)
      • May instead use Carotid CTA or US (Carotid US slightly less sensitive than MRA)[10] (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 180 mg/dL
  • Prevent fever
  • HOB > 30°

tPA Candidate

Non-tPA Candidate

  • Hypertension
    • Allow permissive hypertension
    • If SBP > 220 or DBP > 120, lower by 25% over 24 hrs (drug of choice is nicardipine)[11]
    • Goal MAP for non-thrombolyzed, MAP < 150, per AHA guidelines[12]
  • Aspirin 325mg (within 24-48hr)
  • Clopidogrel 600 mg load (followed by 75 mg daily for 30-90 days)
    • prevents 15 strokes out of 1000 patients at a cost of 5 additional major noncerebral hemorrhages. [13][14]
  • 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[15]
    • 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
  • AHA guidelines say the following patients are eligible for mechanical thrombectomy:
    • 0-6 hours: pre-stroke mRS 01, ICA or M1 occlusion, age > 18, NIHSS > 5, puncture < 6 hours
    • 0-6 hours: May also be reasonable in carefully selected patients with M2 or M3 occlusions
    • 6-16 hours: anterior circulation LVO who meet DAWN or DEFUSE 3 criteria
    • 16-24 hours: anterior circulation LVO who meet DAWN criteria
  • May require careful patient selection based on last known normal, ICA/prox MCA occlusion, and additional diagnostic studies such as CT perfusion study, Rapid MRI, etc[16]
  • Goal SBP <160 after endovascular therapy [17]



  • Cochrane review showed no benefit in mortality or functional outcomes[18]


  • Admit all acute and subacute ischemic strokes

See Also

External Links


  1. [Finsterer J. Management of cryptogenic stroke. Acta Neurol Belg. 2010 Jun;110(2):135-47. PMID: 20873443].
  2. Macdonell RA, Kalnins RM, Donnan GA. Cerebellar infarction: natural history, prognosis, and pathology. Stroke. 18 (5): 849-55.
  3. 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.
  4. Rezaee A and Jones J et al. Lacunar stroke syndrome. Radiopaedia.
  5. Internal Capsule Stroke. Stanford Medicine Guide.
  6. 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.
  7. Suarez JI, Tarr RW, Selman WR. Aneurysmal subarachnoid hemorrhage. N Engl J Med. 2006; 354(4):387–396.
  8. 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.
  9. ACEP Clinical Policy: Suspected Transient Ischemic Attack full text
  10. Nederkoorn PJ, Mali WP, Eikelboom BC, et al. Preoperative diagnosis of carotid artery stenosis. Accuracy of noninvasive testing. Stroke. 2002;33:2003-2008.
  11. Zha AM, et al. Recommendations for management of large hemispheric infarction. Curr Opin Crit Care. 2015; 21(2):91-8.
  12. Anton Helman. Emergency Medicine Cases. Episode 17 Part 1: Emergency Stroke Controversies. September 2011.
  13. Journal Watch May 17, 2018 Clopidogrel plus Aspirin Has Benefits for TIA or Minor Stroke
  14. Clopidogrel and Aspirin in Acute Ischemic Stroke and High-Risk TIA N Engl J Med 2018; 379:215-225
  15. Berkhemer OA, et al. A randomized trial of intraarterial treatment for acute ischemic stroke. NEJM. 2015; 372(1):11-20.
  16. Thrombectomy For Stroke At 6 To 16 Hours With Selection By Perfusion Imaging Albers, G.W., et al, N Engl J Med 378(8):708, February 22, 2018
  17. Smith M, Reddy U, Robba C, et al. Acute ischaemic stroke: challenges for the intensivist. Intensive Care Med. 2019
  18. Sandercock PA and Soane T. Corticosteroids for acute ischaemic stroke. Cochrane Database Syst Rev. 2011 Sep 7;(9):CD000064.