Carotid Endarterectomy: Indications and Management
Primary Recommendation
For symptomatic patients with 70-99% carotid stenosis, carotid endarterectomy (CEA) should be performed urgently—ideally within 2 weeks of the ischemic event—as this provides an absolute risk reduction of 17% for ipsilateral stroke at 2 years, with a number needed to treat of only 12 patients. 1, 2
Symptomatic Carotid Stenosis: Clear Indications
Severe Stenosis (70-99% by NASCET criteria)
- CEA is definitively indicated for patients with recent TIA or non-disabling stroke and ipsilateral 70-99% stenosis, reducing 5-year ipsilateral stroke risk from 26% (medical therapy) to 9% (CEA plus medical therapy). 1
- The perioperative stroke/death rate must be <6% for symptomatic patients to maintain benefit. 1, 2
- Timing is critical: Surgery within 2 weeks of the last ischemic event provides maximum benefit, particularly for patients with hemispheric (not just retinal) symptoms. 1, 2
- Men, patients ≥75 years old, and those with hemispheric stroke (versus TIA alone) derive the greatest benefit. 1, 3
Moderate Stenosis (50-69% by NASCET criteria)
- CEA provides modest benefit with 5-year ipsilateral stroke rates of 15.7% (CEA) versus 22.2% (medical therapy alone), requiring treatment of 15 patients to prevent one stroke over 5 years. 1, 3
- This translates to an NNT of 77 patients per year—a marginal benefit that demands exceptional surgical skill. 1
- Patient selection is paramount: Men with recent hemispheric stroke and life expectancy >5 years benefit most. 1, 3
- Women, patients with retinal symptoms only, and those with TIA (not stroke) show minimal to no benefit in this stenosis range. 4
- The 30-day perioperative risk must be <6.7% to justify intervention. 1
Mild Stenosis (<50%)
- CEA is not indicated for stenosis <50%, as no benefit over medical therapy has been demonstrated (5-year stroke rate 14.9% with CEA versus 18.7% medical therapy, p=0.16). 3
Asymptomatic Carotid Stenosis: Controversial Territory
Current Evidence and Declining Benefit
- Modern medical therapy has dramatically reduced the benefit of CEA for asymptomatic stenosis. Annual stroke risk with contemporary medical management is now ≤1% per year, compared to historical rates of 2.2% per year. 5
- The ACAS trial showed 5-year stroke risk of 5.1% with CEA versus 11% with medical therapy alone, but this was conducted before widespread statin use. 1, 5
- Patients on lipid-lowering therapy in ACST had absolute benefit from CEA of only 0.6% per year versus 1.5% per year for those not on statins. 5
When CEA May Be Considered for Asymptomatic Stenosis
CEA may be reasonable for highly selected asymptomatic patients with 70-99% stenosis only if ALL of the following criteria are met: 1, 5
- Perioperative stroke/death rate documented at <3% at the treating institution 1, 2
- Life expectancy >5 years 1
- Patient preference after thorough discussion of marginal benefit 5
- Age <80 years (older patients have higher perioperative risk) 1
- Absence of severe comorbidities (NYHA class III/IV heart failure, LVEF <30%, severe COPD, recent MI within 4 weeks) 1
- However, the effectiveness of CEA versus contemporary aggressive medical therapy alone is not well established for asymptomatic stenosis. 5
Contraindications to CEA
Absolute Contraindications
- Chronic total occlusion of the target carotid artery 1
- Severe disability from prior stroke that precludes preservation of useful function (Modified Rankin Scale ≥3) 1
- Acute stroke in evolution 1
High-Risk Anatomical Features
Unfavorable anatomy includes: 1
- Stenosis distal to C2 vertebra or proximal intrathoracic stenosis
- Previous ipsilateral CEA (restenosis)
- Contralateral vocal cord paralysis
- Open tracheostomy
- Prior radical neck surgery or radiation therapy
For these high-risk anatomical scenarios, carotid artery stenting (CAS) should be considered instead of CEA. 6, 2
High-Risk Medical Comorbidities
Consider CAS over CEA when: 1, 6
- Age ≥80 years
- NYHA class III/IV heart failure or LVEF <30%
- Class III/IV angina or left main/multivessel CAD
- Need for cardiac surgery within 30 days
- MI within 4 weeks
- Severe chronic lung disease
Perioperative Management
Preoperative Assessment
- Confirm stenosis severity with duplex ultrasound plus one confirmatory imaging method (CTA, MRA, or catheter angiography). 1
- Assess for contralateral carotid occlusion, intracranial stenosis, and collateral circulation—these high-risk features paradoxically predict better outcomes with CEA than medical therapy alone. 4
- Evaluate cardiac risk: patients with history of MI, angina, or hypertension are 1.5 times more likely to experience perioperative medical complications. 7
Antiplatelet Therapy
- Continue aspirin 81-325 mg daily perioperatively and indefinitely post-CEA. 2
- Do not routinely add dual antiplatelet therapy for CEA (unlike CAS, which requires DAPT). 6
Lipid Management
- Initiate high-intensity statin therapy targeting LDL-C <55 mg/dL with >50% reduction from baseline. 2
Postoperative Surveillance
- Perform duplex ultrasound within the first month post-CEA, then annually to detect restenosis or contralateral disease progression. 5, 2
- Patients with stenosis progression ≥2 categories in 1 year are at higher risk for ipsilateral ischemic events. 5
Carotid Artery Stenting as Alternative
When to Choose CAS Over CEA
CAS is appropriate for symptomatic patients with 70-99% stenosis who have: 6, 2
- Post-radiation stenosis
- Restenosis after prior CEA
- Hostile neck anatomy (obesity, tracheostomy, contralateral laryngeal nerve palsy)
- High surgical risk from medical comorbidities (see above)
Critical Performance Standards for CAS
- Perioperative stroke/death rate must be <6% for symptomatic patients and <3% for asymptomatic patients. 6
- Operator volume and experience critically impact outcomes—low-volume operators have significantly higher mortality rates. 6
- Mandatory dual antiplatelet therapy (aspirin plus clopidogrel) for at least 1 month after CAS. 6
Age Considerations
- For patients >70 years old, CEA is strongly preferred over CAS due to higher periprocedural stroke and death rates with stenting in older patients. 2
Common Pitfalls to Avoid
Do not perform CEA for asymptomatic stenosis <70% or symptomatic stenosis <50%—no benefit demonstrated. 1, 3
Do not delay surgery beyond 2 weeks for symptomatic severe stenosis—early intervention provides maximum benefit. 1, 2
Do not proceed with CEA if institutional perioperative complication rates exceed 6% for symptomatic or 3% for asymptomatic stenosis—the benefit is negated. 1, 2
Do not assume asymptomatic stenosis requires intervention—contemporary medical therapy may be equally effective with stroke risk ≤1% per year. 5
Do not use CAS in patients >70 years old without compelling contraindication to CEA—age-related increased stroke risk with stenting. 2
Do not forget that medical complications (MI, cardiovascular events) occur in 8.1% of CEA patients, particularly those with pre-existing cardiovascular disease. 7