Table Of Contents

Carotid Artery Disease

General

• Pathophysiology
  • Atherosclerotic stenosis of the carotid artery, primarily at the bifurcation into the internal carotid artery.
• Considered symptomatic if the patient has experienced stroke symptoms (e.g., stroke, transient ischemic attack (TIA), amaurosis fugax) within the past 6 months.
  • Events Occur due to thrombus formation leading to either a low flow state or embolization.

Clinical Presentation

• Stroke
  • Anterior circulation TIA/stroke features
    • Middle cerebral artery (MCA)
    • Anterior cerebral artery (ACA)
    • Retinal artery
• Amaurosis Fugax
  • Transient monocular blindness.
• Hollenhorst Plaques
  • Cholesterol emboli in the retinal arterioles (rare but specific finding).
• Carotid Bruit
  • Audible vascular sound over the carotid artery area.

Hollenhorst Plaques

Diagnosis

• Imaging Modalities (similar efficacy)
  • Carotid Duplex Ultrasound (US) (first-line)
  • Magnetic Resonance Angiography (MRA)
  • Computed Tomography Angiography (CTA)

Management

1. Symptomatic Intervention

   • 100% Stenosis
     • Medical management
   • 70-99% Stenosis
     • Surgery
       • Carotid endarterectomy (ideally performed between 3-14 days after stroke symptoms)
       • Carotid artery stenting (if high risk for surgery or lesion is not surgically accessible)
   • <50% Stenosis
     • Medical management

   <aside> 💡 In case of 50-69% Stenosis

   • Medical management
   • +/- Carotid endarterectomy (can be considered only if reasonable life expectancy) </aside>

2. Asymptomatic Intervention

   • 80-99% Stenosis
     • Carotid endarterectomy (if low surgical risk/long life expectancy)
     • Intensive medical therapy
   • <80% Stenosis
     • Medical management
     • Periodic (eg, annual) carotid duplex surveillance to detect any progression.

• UWT Indication for Carotid Endarterectomy
• Another Algorithm

Carotid Artery Dissection

General

• Pathophysiology
  • Mechanism
    • Injury to arterial intima allows blood to flow into the vessel wall, forming a false lumen, aneurysm, or intramural hematoma.
      • Hematoma formation between arterial wall layers → dissection through the layers → luminal stenosis or occlusion → neurologic deficits due to impaired cerebral perfusion.
    • Can lead to arterial obstruction or thromboembolic events, causing cerebral ischemia (stroke, TIA).

Risk Factors

• May occur spontaneously or after infections or minor trauma (e.g., sports injuries, falls).
  • Common when falling when something in the mouth
• Common in patients in their fourth to fifth decades.
• Associated with connective tissue disorders
  • Fibromuscular dysplasia
  • Ehlers-Danlos syndrome

Clinical Features

• Sudden-onset jaw pain, headache, and neurologic deficits
• Thunderclap headache +- neck, or face pain
  • Explanation
• Other common findings
  • Partial Horner Syndrome
    • Distension of sympathetic fibers along the internal carotid artery.
    • Results in partial Horner syndrome (ptosis, miosis).
      • Explanation
  • Tinnitus
  • Carotid bruit
  • Cranial neuropathies
  • Symptoms consistent with ischemia in the anterior or middle cerebral artery distribution

Diagnosis

• MRA and CTA
  • First-line imaging studies
  • Findings
    • Irregular and asymmetrical vessels
    • Intimal flap
• Angiography
• Duplex ultrasonography
  • High-resistance flow pattern or absence of flow on Doppler ultrasound

Management

• Administration of antithrombotic therapy (e.g., aspirin, anticoagulation)
• Treatment similar to ischemic stroke
  • Alteplase (thrombolysis)
    • Risk of extension of the hematoma is considered, but generally similar risks to non–dissection-related ischemic strokes.
  • Mechanical thrombectomy for large vessel occlusions (e.g., middle cerebral artery).
  • Endovascular stenting