carotid endarterectomy in asymptomatic carotid stenosis patients

Last reviewed 01/2018

The role of carotid endarterectomy in patients with asymptomatic carotid artery stenosis is controversial because:

  • the risk of stroke is lower than in patients with symptomatic stenoses
  • the importance of operative complications becomes correspondingly more significant

A meta-analysis showed that carotid endarterectomy (1):

  • in an analysis of trials involving 2440 patients with stenosis >=50%
    • approximately 30% reduction in the combined end-point of ipsilateral stroke plus perioperative death and stroke
    • an absolute risk reduction for this end-point of only 2% over 3.1 years
    • this data would suggest that patients with an asymptomatic carotid artery stenosis should not routinely undergo endarterectomy unless other factors suggest a high risk for stroke

However a more recent trial investigated the use of immediate carotid endarterectomy in patients with unilateral or bilateral carotid artery stenosis (>= 60%) but no stroke or ischaemia in the previous 6 months, for whom both physician and patient were substantially uncertain whether to choose immediate carotid endarterectomy or deferral of any carotid endarterectomy until a more definite need for it was thought to have arisen (2):

  • 3120 patients - mean age 68 years, 66% men
  • this trial revealed that asymptomatic patients younger than 75 years of age with carotid diameter reduction about 70% or more on ultrasound (many of whom were on aspirin, antihypertensive, and, in recent years, statin therapy), immediate carotid endarterectomy halved the net 5-year stroke risk from about 12% to about 6% (including the 3% perioperative hazard). Half this 5-year benefit involved disabling or fatal strokes. Note also that the authors stated that outside trials, inappropriate selection of patients or poor surgery could obviate such benefits


  1. Benavente, O, Moher, D, Pham, B. (1998) Carotid endarterectomy for asymptomatic carotid stenosis: a meta-analysis. BMJ; 317: 1477-80.
  2. Halliday A et al. Prevention of disabling and fatal strokes by successful carotid endarterectomy in patients without recent neurological symptoms: randomised trial. Lancet 2004; 363:1491-502