This is the current release of the guideline.

Definitions of the classification of the recommendations (A, B, C, U) and classification of the evidence (Class I through Class IV) are provided at the end of the "Major Recommendations" field.

1. Carotid endarterectomy (CE) is established as effective for recently symptomatic (within previous 6 months) patients with 70 to 99% internal carotid artery (ICA) angiographic stenosis (Level A). CE should not be considered for symptomatic patients with less than 50% stenosis (Level A). CE may be considered for patients with 50 to 69% symptomatic stenosis (Level B) but the clinician should consider additional clinical and angiographic variables (Level C, see below). It is recommended that the patient have at least a 5-year life expectancy and that the perioperative stroke/death rate should be <6% for symptomatic patients (Level A). Medical management is preferred to CE for symptomatic patients with <50% stenosis (Level A).
2. It is reasonable to consider CE for patients between the ages of 40 and 75 years and with asymptomatic stenosis of 60 to 99% if the patient has an expected 5-year life expectancy and if the surgical stroke or death frequency can be reliably documented to be <3% (Level A). The 5-year life expectancy is important since perioperative strokes pose an up front risk to the patient and the benefit from CE emerges only after a number of years.
3. No recommendation can be provided regarding the value of emergent CE in patients with a progressing neurologic deficit (Level U).
4. Clinicians should consider patient variables in CE decision making. Women with 50 to 69% symptomatic stenosis did not show clear benefit in previous trials. In addition, patients with hemispheric transient ischemic attack (TIA)/stroke had greater benefit from CE than patients with retinal ischemic events (Level C). Clinicians should also consider several radiologic factors in decision making about CE. For example, contralateral occlusion erases the small benefit of CE in asymptomatic patients whereas in symptomatic patients, it is associated with increased operative risk but persistent benefit (Level C). CE for patients with angiographic near-occlusion in symptomatic patients is associated with a trend toward benefit at 2 years but not associated with a clear long-term benefit (Level C). Patients operated on within 2 weeks of their last TIA or mild stroke derive greater benefit from CE (Level C).
5. Symptomatic and asymptomatic patients undergoing CE should be given aspirin (81 or 325 mg/day) prior to surgery and for at least 3 months following surgery to reduce the combined endpoint of stroke, myocardial infarction, and death (Level A). Although data are not available, it is recommended that aspirin (81 or 325 mg/day) be continued indefinitely provided that contraindications are absent. Aspirin at 650 or 1,300 mg/day is less effective in the perioperative period. The data are insufficient to recommend the use of other antiplatelet agents in the perioperative setting.
6. At this time the available data are insufficient to declare either CE before or simultaneous with coronary artery bypass graft (CABG) as superior in patients with concomitant carotid and coronary artery occlusive disease (Level U).
7. For patients with severe stenosis and a recent TIA or nondisabling stroke, CE should be performed without delay, preferably within 2 weeks of the patient's last symptomatic event (Level C). There is insufficient evidence to support or refute the performance of CE within 4 to 6 weeks of a recent moderate to severe stroke (Level U).

Definitions:

Classification of Evidence

Class I: Prospective, randomized, controlled clinical trial (RCT) with masked outcome assessment, in a representative population. The following are required:

1. Primary outcome(s) clearly defined.
2. Exclusion/inclusion criteria clearly defined.
3. Adequate accounting for dropouts and crossovers with numbers sufficiently low to have minimal potential for bias.
4. Relevant baseline characteristics are presented and substantially equivalent among treatment groups or there is appropriate statistical adjustment for differences.

Class II: Prospective matched group cohort study in a representative population with masked outcome assessment that meets a-d above OR a RCT in a representative population that lacks one criterion a-d.

Class III: All other controlled trials (including well-defined natural history controls or patients serving as own controls) in a representative population, where outcome is independently assessed, or independently derived by objective outcome measurement.

Class IV: Evidence from uncontrolled studies, case series, case reports, or expert opinion.

Classification of Recommendation

A = Established as effective, ineffective, or harmful for the given condition in the specified population. (Level A rating requires at least two consistent Class I studies.)

B = Probably effective, ineffective, or harmful for the given condition in the specified population. (Level B rating requires at least one Class I study or at least two consistent Class II studies.)

C = Possibly effective, ineffective, or harmful for the given condition in the specified population. (Level C rating requires at least one Class II study or two consistent Class III studies.)

U = Data inadequate or conflicting; given current knowledge, treatment is unproven.

None provided

The type of supporting evidence is identified and graded for each recommendation (see "Major Recommendations" field).

Not applicable: The guideline was not adapted from another source.

2005 Sep

American Academy of Neurology - Medical Specialty Society

American Academy of Neurology (AAN)

Therapeutics and Technology Assessment Subcommittee

Primary Authors: Chaturvedi, MD; A. Bruno, MD; T. Feasby, MD; R. Holloway, MD, MPH; O. Benavente, MD; S.N. Cohen, MD; R. Cote, MD; D. Hess, MD; J. Saver, MD; J.D. Spence, MD; B. Stern, MD; and J. Wilterdink, MD

Therapeutics and Technology Assessment Subcommittee Members: Douglas S. Goodin, MD (Chair); Yuen T. So, MD, PhD (Vice-Chair); Carmel Armon, MD, MHS; Richard M. Dubinsky, MD, MPH; Mark Hallett, MD; David Hammond, MD; Cynthia Harden, MD; Chung Hsu, MD, PhD (ex-officio); Andres M. Kanner, MD (ex-officio); David S. Lefkowitz, MD; Janis Miyasaki, MD; Michael A. Sloan, MD, MS; James C. Stevens, MD

The authors report no conflicts of interest.

This is the current release of the guideline.

This summary was completed by ECRI on December 29, 2005.

This NGC summary is based on the original guideline, which is copyrighted by the American Academy of Neurology.