Dual Antiplatelet Therapy After Carotid Endarterectomy

Primary Recommendation

The American College of Chest Physicians recommends single antiplatelet therapy over dual antiplatelet therapy for patients after carotid endarterectomy (Grade 2B) 1
Single antiplatelet therapy with either aspirin (75-100 mg daily) or clopidogrel (75 mg daily) is preferred over dual antiplatelet therapy for patients following carotid endarterectomy 1
This recommendation applies to both previously symptomatic and asymptomatic patients who undergo the procedure, as the evidence for symptomatic carotid stenosis is considered applicable to all post-endarterectomy patients 1

Antiplatelet therapy reduces stroke risk after carotid endarterectomy (OR 0.58; 95% CI 0.34-0.98), translating to 34 fewer strokes per 1,000 patients treated 1
Low-dose aspirin (81-325 mg) is superior to high-dose aspirin (650-1,300 mg), with lower rates of combined stroke, MI, and death at 30 days (5.4% vs 7.0%) and 3 months (6.2% vs 8.4%) 1

The only scenario where dual antiplatelet therapy is recommended after carotid intervention is following carotid artery stenting (CAS), not endarterectomy 3
For CAS specifically, dual antiplatelet therapy with aspirin (81-325 mg daily) plus clopidogrel (75 mg daily) is recommended for a minimum of 30 days (Class I, Level C) 3
If a patient requires dual antiplatelet therapy for another indication (such as recent coronary stenting), clopidogrel plus aspirin may be used for up to 1 year post-CEA 1

Timing of antiplatelet initiation: antiplatelet therapy should be initiated perioperatively and continued long-term for secondary stroke prevention 1
For patients on anticoagulation who undergo CEA: antiplatelet therapy should be stopped and anticoagulation alone continued when safe from post-operative bleeding perspective (typically 3-14 days after surgery) 4

Do not extrapolate CAS guidelines to CEA patients: the requirement for dual antiplatelet therapy applies to carotid stenting, not endarterectomy, due to different thrombotic mechanisms 3
Avoid high-dose aspirin: doses above 325 mg increase bleeding complications without additional benefit 1
Do not discontinue antiplatelet therapy prematurely: long-term single antiplatelet therapy is essential for secondary stroke prevention and should be continued indefinitely unless contraindicated 1