From Wiki Journal Club
Jump to navigation Jump to search
Barnett HJ, et al. "Benefit of carotid endarterectomy in patients with symptomatic moderate or severe stenosis". The New England Journal of Medicine. 1998. 339(20):1415-25.
PubMedFull textPDF

Clinical Question

In patients with symptomatic stenosis, does CEA reduce risk of death or stroke?

Bottom Line

CEA reduces the 5-year risk of death or stroke by 29% among patients with symptomatic high-moderate (50-69%) carotid stenosis.

Major Points

Prior studies had demonstrated the benefit of carotid endarterectomy (CEA) in patients with severe carotid stenosis, but NASCET was the first large, well-designed trial to study CEA in patients with low-moderate (<50%), high-moderate (50-69%), and severe (≥70%) stenosis. Those with symptomatic 50-69% stenosis had a 29% reduction in the 5-year risk of death or stroke, while those with <50% stenosis had no such benefit. Those with ≥70% stenosis received such a dramatic benefit that this study arm was prematurely stopped and all patients with severe stenosis were subsequently referred for CEA.


  • The 2005 American Academy of Neurology guidelines[1] make the following recommendations:
    • CEA if symptomatic in previous 6 months and 70-99% stenosis (level A)
    • CEA consideration if symptomatic and 50-69% stenosis (level B)
    • No consideration for CEA if symptomatic and <50% stenosis (level A)


  • Multicenter, parallel-group, randomized controlled trial
  • N=2,226
    • CEA (n=1,108)
    • Medical therapy (n=1,108)
  • Setting: 106 centers worldwide
  • Enrollment: 1988-1991
  • Mean follow up: 5 years


Inclusion Criteria

  • Symptomatic stenosis <70% in ipsilateral internal carotid artery imaged within 180 days
    • TIA or nondisabling stroke (Rankin score <3) were considered symptoms of stenosis
    • Stenosis assessed on selective angiography
      • Minimum 2 projections showing cervical and intracranial carotid arteris and major branches
      • Ipsilateral atheromatous stenosis must be >30%, <100%, and be technically suitable for CEA
  • CT head, carotid doppler US, and CXR required

Exclusion Criteria

  • Age >80 years (excluded in first phase only)
  • Lack of angiographic evidence of ipsilateral stenosis
  • Intracranial stenosis more clinically significant than cervical lesion
  • Other lesion limiting life expectancy to <5 years
  • Cerebral infarction eliminating useful function in affected vascular distribution
  • Nonatherosclerotic carotid disease
  • Carotid lesions likely to cause cardioembolism
  • History of ipsilateral endarterectomy


  • Study divided into two phases
    • First phase: moderate/severe stenosis
    • Second phase: moderate stenosis alone
  • Randomized to CEA or medical therapy
    • Patients with moderate stenosis who progressed to severe stenosis were offered endarterectomy
  • Patients received antiplatelet therapy (typically aspirin, dose adjusted to investigator) and antihypertensive and cholesterol-lowering drugs when indicated
  • Surgical technique decided by individual surgeons, but simultaneous vascular procedures were discouraged
  • Neurological follow up at 1, 3, 6, 9, and 12 months, then every 4 months
  • Carotid doppler ultrasound performed at 1 month, annually, and after cerebrovascular events


Comparisons are CEA vs. medical management.

Primary Outcomes

Ipsilateral stroke at 5 years
With 50-69% stenosis
15.7% vs. 22.2% (RR 0.71; 95% CI 0.48-0.93; P=0.045), NNT=15
With <50% stenosis
14.9% vs. 18.7% (P=0.16)

Secondary Outcomes

Death or stroke at 30 days
With 50-69% stenosis
33.2% vs. 43.3% (RR 0.77; P=0.005), NNT 10
With <50% stenosis
36.2% vs. 37% (RR 0.98; P=0.97)

Subgroup Analysis

  • Factors predicting perioperative stroke or death (P<0.05):
    • Contralateral carotid occlusion
    • Left-sided carotid disease
    • Taking aspirin <650mg daily
    • Absence of MI/angina
    • CT or MR imaging evidence of ipsilateral cerebral infarction
    • Diabetes
    • Hypertension
  • Factors predicting durability of CEA benefit (P<0.05):
    • Male sex
    • Recent stroke
    • Recent hemispheric symptoms
    • Taking aspirin ≥650mg daily


Funded by NINDS, with SmithKline Beechman providing aspirin.

Further Reading