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• Ischemic stroke


  Blood vessel obstruction leading to ischemic core surrounded by ischemic penumbra (area of potentially salvageable tissue with reduced blood flow)
• Ischemic strokes account for 80-85% of all strokes
• Ischemic stroke recovery


  Reperfusion within 3-4 hours can recover ischemic penumbra
• Causes of ischemic stroke


  • Thromboembolism
  • Hypercoagulable state
  • Hypoperfusion
  • Other unusual causes (aortic dissection, vasculitis, drug abuse)
• Thromboembolism


  Thrombosis at atheromatous plaque or embolism from distant atheromatous plaque or cardiac source
• Embolism from cardiac source is more likely to undergo hemorrhagic transformation
• Hypercoagulable state


  Antiphospholipid syndrome
• Hypoperfusion


  Watershed infarction
• Non-modifiable risk factors for ischemic stroke


  • Age
  • Family history
  • Race (African American)
  • Gender (estrogen is protective in premenopausal females)
• Modifiable risk factors for ischemic stroke


  • Hypertension
  • Previous stroke/TIA
  • Heart disease (Atrial fibrillation)
  • Hyperlipidemia
  • Smoking
  • Alcohol
  • Cocaine & amphetamine abuse
  • Hypercoagulability
  • Polycythemia
  • Sickle cell disease
  • Dissection
  • Vasculitis
• Hypertension


  The #1 most important modifiable risk factor for ischemic stroke
• Symptoms of ischemic stroke


  • Negative symptoms (loss of function)
  • Depend on territory affected (anterior vs. posterior vs. brainstem)
• Middle cerebral artery stroke


  • Commonest site for embolism
  • Face & arm > leg affected
  • Contralateral homonymous hemianopia with ipsilateral gaze deviation
  • Aphasia if dominant hemisphere affected
  • Apraxia, agraphia, neglect, agraphesthesia, astereognosis if non-dominant hemisphere affected
• Anterior cerebral artery stroke


  • Leg > arm affected
  • Cognitive or personality changes
  • Abulia if bilateral
  • Apraxia (inability to perform tasks)
• Posterior cerebral artery stroke


  • Contralateral homonymous hemianopia with macular sparing
  • Visual agnosia
• Posterior circulation (vertebrobasilar) stroke


  • Diplopia, vertigo, dizziness, ataxia, dysarthria, dysphagia
• Complications of Lacunar Infarcts


  • Hemorrhage into the infarction
  • Cerebral edema (increased ICP)
  • Seizures
• Lacunar Infarcts


  Small, deep infarcts caused by occlusion of penetrating brain arteries in deeper brain structures: Basal ganglia, internal capsule, thalamus, and pons
• Types of Lacunar Infarcts


  • Pure motor
  • Pure sensory
  • Ataxic hemiparesis
  • Sensorimotor
  • Dysarthria – Clumsy hand syndrome
• Pure motor


  • Most common
  • Weakness on one side without sensory or cortical
  • Posterior limb of internal capsule
• Pure sensory


  • Numbness without weakness or cortical
  • VPL nucleus of thalamus
• Ataxic hemiparesis


  • Ipsilateral weakness & limb ataxia out of proportion to motor deficit
  • +/- dysarthria, nystagmus, gait deviation
• Sensorimotor


  • Weakness & numbness on one side without cortical
  • Posterolateral thalamus + posterior limb of internal capsule
• Dysarthria – Clumsy hand syndrome


  • Least common
  • Facial weakness, dysarthria, dysphagia, slight weakness clumsiness of one hand
  • Lesion in the pons
• Brain CT


  Modality of choice for diagnosis of cerebrovascular accidents
• Brain CT


  1. Exclude hemorrhage

  2. Identify ischemic (hypodense) vs. hemorrhagic (hyperdense)
• Blood tests


  • CBC
  • Blood sugar, lipid profile
  • Coagulation profile
• ECG


  Identify acute MI or AF
• Echo & Holter


  Diagnostic tests
• Carotid duplex ultrasound


  Identify carotid stenosis
• Management


  1. Protect the airway

  2. Monitor blood glucose, temperature and blood pressure

  3. Do not lower the blood pressure (increases the ischemic core)

  4. BP goal <220/110 without tPA and <185/110 with tPA

  5. Maintain serum glucose < 140 mg/dl (<7.8)àavoid hyperglycemia
• Management after excluding hemorrhage with CT


  1. If within the 3 to 4.5 hours window period: start thrombolytics (tPA), wait for 24 hours, then start aspirin

  2. If after the window period: start aspirin immediately (300 mg then 75-150 mg/day oral via NGT or rectally)

  3. If already on aspirin: add dipyridamole or switch to clopidogrel
• Thrombolytics (tPA)


  • Inclusion criteria (within window): NIHSS > or equal to 4, Baseline CT shows no ICH or early hypodensity affecting > 1/3 of MCA territory
  • Exclusion criteria: anything increasing the chance of bleeding, blood on CT – recent (2 weeks) surgery or bleeding or ischemic stroke - severe head trauma in past 3 months - previous ICH - coagulation problems, BP>185or>110, Glucose < 2.8 or > 22
• Management if tPA complicated by intracerebral hemorrhage


  1. D/C tPA, take blood for coagulation profile, type & cross match, fibrinogen, immediate CT & contrast neurosurgery

  2. Administer: 6-8 units IV cryoprecipitate & platelets ± recombinant activated factor 7
• High dose statins


  Anti-inflammatory effect, regardless of LDL level
• IV fluids


  Use NS (avoid dextrose containing fluidsàmore edema)
• Monitor for signs of increased ICP


  Treat with hyperventilation and mannitol
• Endovascular thrombectomy


  Catheter removal of the clot, useful up to 8-12 hours in occlusion of the proximal anterior circulation