What is the recommended treatment for carotid artery stenosis?

Treatment of Carotid Artery Stenosis

The treatment of carotid artery stenosis depends critically on whether the patient is symptomatic or asymptomatic, the degree of stenosis, and patient-specific factors—with optimal medical therapy forming the foundation for all patients, and revascularization reserved for specific high-risk scenarios. 1

Initial Assessment and Diagnosis

All patients require neurological evaluation by a vascular team including a neurologist to determine symptom status. 1

• Use duplex ultrasonography (DUS) as first-line imaging to diagnose and quantify internal carotid artery (ICA) stenosis 1
• Apply the NASCET method (not ECST) to assess stenosis severity 1
• If DUS is equivocal, proceed with CTA or MRA for definitive assessment 1

Key distinction: Symptomatic patients are those with ipsilateral retinal or hemispheric ischemic symptoms (TIA, amaurosis fugax, or stroke) within the past 6 months; all others are asymptomatic 1

Optimal Medical Therapy (OMT) - Foundation for ALL Patients

Every patient with carotid stenosis, regardless of stenosis severity or symptom status, requires intensive medical therapy. 1

Antiplatelet Therapy

For asymptomatic patients:

• Low-dose aspirin (75-325 mg daily) or clopidogrel 75 mg daily 1

For symptomatic patients NOT undergoing immediate revascularization:

• Dual antiplatelet therapy (DAPT) with aspirin plus clopidogrel 75 mg for at least 21 days (up to 90 days may be considered), then transition to single antiplatelet therapy 1
• This reduces asymptomatic cerebral embolization and stroke recurrence 1

Lipid Management

• High-dose statin therapy (atorvastatin 80 mg daily) for all patients to achieve LDL <70 mg/dL 1
• The SPARCL trial demonstrated 33% stroke reduction and 56% reduction in need for carotid revascularization in carotid stenosis patients 1

Blood Pressure Control

• Target <140/90 mmHg in asymptomatic patients 1
• In symptomatic patients beyond the hyperacute period, antihypertensive treatment is indicated but avoid excessive lowering that could compromise cerebral perfusion 1

Risk Factor Modification

• Mandatory smoking cessation interventions 1
• Diabetes optimization 2
• The combination of these interventions can achieve up to 80% relative stroke risk reduction 2

Symptomatic Carotid Stenosis: Revascularization Decisions

Severe Stenosis (70-99%)

Carotid endarterectomy (CEA) is recommended for symptomatic 70-99% ICA stenosis, provided the documented 30-day risk of procedural death/stroke is <6%. 1

• Timing is critical: Perform CEA within 14 days of symptom onset 1
• Earlier intervention (within 2 weeks) provides maximum benefit 1, 3
• However, avoid CEA within the first 48 hours in high-risk patients (acute carotid occlusion, major neurological deficit, large infarction >1/3 MCA territory, hemorrhagic transformation, impaired consciousness) 1

CEA is preferred over carotid artery stenting (CAS) in:

• Patients ≥70 years of age 1
• When revascularization is planned within 1 week of index stroke 1
• Average surgical risk patients 1

CAS may be considered as alternative in:

• High surgical risk patients with 60-99% stenosis and high-risk features 1
• Perioperative stroke/death rate must still be <6% 1

Moderate Stenosis (50-69%)

CEA is recommended for symptomatic 50-69% stenosis if perioperative morbidity/mortality risk is <6%, considering patient-specific factors (age, sex, comorbidities). 1

• Benefit is less robust than with severe stenosis but still significant 1

Mild Stenosis (<50%)

Revascularization is NOT recommended for symptomatic patients with <50% stenosis. 1, 4

• Treat with intensive OMT only 4

Asymptomatic Carotid Stenosis: Conservative Approach

Routine revascularization is NOT recommended in asymptomatic patients with ICA stenosis in the absence of high-risk features and with life expectancy <5 years. 1

When Revascularization May Be Considered

In highly selected asymptomatic patients with 60-99% stenosis AND high-risk features:

• Life expectancy >5 years 1
• Documented perioperative stroke/death rate <3% 1
• Decision made by vascular team after careful risk-benefit assessment 1

For average surgical risk patients >75 years with 60-99% stenosis and high-risk features:

• CEA in addition to OMT should be considered 1

High-risk features include: silent brain infarction in corresponding territory, microembolization on intracranial Doppler, stenosis progression, irregular plaque, contralateral occlusion, tandem intracranial stenosis 1

Perioperative Antiplatelet Management

For patients undergoing CEA:

• Continue aspirin 75-325 mg daily perioperatively 1
• Clopidogrel addition should be decided case-by-case 5

For patients undergoing CAS:

• DAPT with aspirin plus clopidogrel for at least 1 month post-procedure 1
• Then transition to long-term single antiplatelet therapy 1

Follow-Up Protocol

Annual follow-up is mandatory for all patients with carotid stenosis. 1

• Assess neurological symptoms, cardiovascular risk factors, and treatment adherence yearly 1
• DUS surveillance within first month after revascularization 1
• Monitor for stenosis progression in medically managed patients 4

Critical Pitfalls to Avoid

• Never assume asymptomatic stenosis requires intervention—the risk of stroke with modern medical therapy is lower than previously thought, and most asymptomatic patients do not benefit from revascularization 1, 2
• Do not delay CEA beyond 14 days in symptomatic patients—benefit decreases significantly with time 1
• Avoid revascularization if operator's documented stroke/death rate exceeds 6% for symptomatic or 3% for asymptomatic patients—the procedural risk negates any benefit 1
• Do not use ECST method for stenosis measurement—only NASCET method is recommended 1
• Never withhold intensive medical therapy regardless of whether revascularization is performed—OMT is the cornerstone of stroke prevention 1, 4