Management of Severe Stenosis of the Proximal Left Internal Carotid Artery Due to Atheromatous Plaques

Risk Stratification

• The American College of Cardiology recommends carotid revascularization for symptomatic patients with stenosis >50% and asymptomatic patients with stenosis >60-70% who have high-risk plaque features 1, 2
• Symptomatic carotid stenosis (recent stroke or TIA within past 2 weeks): Revascularization is beneficial for stenosis >50% 1, 3
• Risk factors that increase stroke risk: Plaque morphology (intraplaque hemorrhage, inflammation, ulceration), plaque progression, and embolic signals 2, 4

Diagnostic Evaluation

• Duplex ultrasound (DUS) is the first-line investigation for identifying stenosis, but has limitations in precise determination of moderate-to-high-grade stenosis 4, 5
• Cross-sectional angiography (CTA or MRA) provides more accurate assessment and can image the cerebral circulation 4, 6
• Plaque morphology assessment using MRI can detect intraplaque hemorrhage (IPH), which is a strong predictor of stroke risk (HR 10.2 for symptomatic and HR 7.9 for asymptomatic patients) 4, 7

Management Options

• The American Heart Association recommends antiplatelet therapy with daily aspirin (75-325 mg) for all patients with carotid stenosis 8
• Lipid-lowering therapy with high-intensity statins is recommended for all patients with carotid stenosis 4
• Carotid endarterectomy (CEA) is indicated for symptomatic patients with stenosis >50% and asymptomatic patients with stenosis >60% and high-risk features 1, 3
• Carotid artery stenting (CAS) is an alternative to CEA, with similar indications and cerebral protection using proximal protection systems 10

Special Considerations

• Hospital factors, such as larger hospitals with dedicated intensive care units and experienced specialists, can improve outcomes 10
• A multidisciplinary approach, including collaboration between neurology, vascular surgery, cardiology, and interventional radiology, can improve outcomes 1
• Plaque vulnerability markers, such as intraplaque hemorrhage, thin/ruptured fibrous cap, and inflammation, increase stroke risk independent of stenosis severity 4

Common Pitfalls to Avoid

• Delayed intervention for symptomatic patients can diminish the benefit of revascularization 3, 9
• Overreliance on stenosis degree alone can lead to inaccurate assessment, as plaque morphology and vulnerability features are important risk factors independent of stenosis severity 4, 7
• Inadequate imaging, such as using only DUS without confirmatory cross-sectional imaging, can lead to inaccurate assessment of stenosis severity 4, 5
• Underestimating associated risks, such as the higher risk of myocardial infarction than stroke in patients with carotid stenosis, can lead to inadequate management 3