Intervention Review

Carotid endarterectomy for asymptomatic carotid stenosis

  1. Brian R Chambers*,
  2. Geoffrey Donnan

Editorial Group: Cochrane Stroke Group

Published Online: 19 OCT 2005

Assessed as up-to-date: 3 NOV 2004

DOI: 10.1002/14651858.CD001923.pub2

How to Cite

Chambers BR, Donnan G. Carotid endarterectomy for asymptomatic carotid stenosis. Cochrane Database of Systematic Reviews 2005, Issue 4. Art. No.: CD001923. DOI: 10.1002/14651858.CD001923.pub2.

Author Information

  1. Austin Health, National Stroke Research Institute, Heidelberg Heights, Victoria, Australia

*Brian R Chambers, National Stroke Research Institute, Austin Health, Heidelberg Repatriation Hospital, 300 Waterdale Road, Heidelberg Heights, Victoria, 3081, Australia.

Publication History

  1. Publication Status: Edited (no change to conclusions)
  2. Published Online: 19 OCT 2005




  1. Top of page
  2. Abstract
  3. Plain language summary
  4. 摘要


Carotid endarterectomy (CEA) is of proven benefit in recently-symptomatic patients with severe carotid stenosis. Its role in asymptomatic stenosis is still debated. The Asymptomatic Carotid Surgery Trial (ACST) more than doubled the number of patients randomised to CEA trials. This revised review incorporates the recently published ACST results.


To determine the effects of CEA for patients with asymptomatic carotid stenosis.

Search methods

We searched the Cochrane Stroke Group Trials Register (searched May 2004), MEDLINE (1966 to May 2004), EMBASE (1980 to June 2004), Current Contents (1995 to January 1997), and reference lists of relevant articles. We contacted researchers in the field to identify additional published and unpublished studies.

Selection criteria

All completed randomised trials comparing CEA to medical treatment in patients with asymptomatic carotid stenosis.

Data collection and analysis

Two reviewers extracted data and assessed trial quality. Attempts were made to contact investigators to obtain missing information.

Main results

Three trials with a total of 5223 patients were included. In these trials, the overall net excess of operation-related perioperative stroke or death was 2.9%. For the primary outcome of perioperative stroke or death or any subsequent stroke, patients undergoing CEA fared better than those treated medically (relative risk (RR) 0.69, 95% confidence interval (CI) 0.57 to 0.83). Similarly, for the outcome of perioperative stroke or death or subsequent ipsilateral stroke, there was benefit for the surgical group (RR 0.71, 95% CI 0.55 to 0.90). For the outcome of any stroke or death, there was a non-significant trend towards fewer events in the surgical group (RR 0.92, 95% CI 0.83 to 1.02). Subgroup analyses were performed for the outcome of perioperative stroke or death or subsequent carotid stroke. CEA appeared more beneficial in men than in women and more beneficial in younger patients than in older patients although the data for age effect were inconclusive. There was no statistically significant difference between the treatment effect estimates in patients with different grades of stenosis but the data were insufficient.

Authors' conclusions

Despite about a 3% perioperative stroke or death rate, CEA for asymptomatic carotid stenosis reduces the risk of ipsilateral stroke, and any stroke, by approximately 30% over three years. However, the absolute risk reduction is small (approximately 1% per annum over the first few years of follow up in the two largest and most recent trials) but it could be higher with longer follow up.


Plain language summary

  1. Top of page
  2. Abstract
  3. Plain language summary
  4. 摘要

Carotid endarterectomy for asymptomatic carotid stenosis

For most people with a narrowing of the carotid artery which is not causing symptoms a surgical operation to remove the narrowing carries a risk and has little benefit. Carotid stenosis is a narrowing of a major artery in the neck taking blood to the brain. This can cause a stroke. If the narrowing is severe and has caused symptoms, surgery to remove the narrowing (carotid endarterectomy) reduces the risk of stroke. However, if the narrowing has not caused any symptoms the risk of stroke is not very high. Although this low risk can be lowered further by surgery, the surgery itself can sometimes cause a stroke or death. The overall effect of surgery is a small benefit.



  1. Top of page
  2. Abstract
  3. Plain language summary
  4. 摘要



頸動脈內膜切除術(CEA)被證實有益於近期有症狀的嚴重頸動脈狹窄病人。它在無症狀狹窄的病人身上角色仍有爭論。Asymptomatic Carotid Surgery Trial(ACST)的試驗人數超出CEA試驗隨機分派的病人數的兩倍之多。此篇修訂的回顧論文也包括了最近發表的ACST的結果。




我們搜尋Cochrane Stroke Group Trials Register (搜尋至2004年5月),MEDLINE (1966年至2004年5月),EMBASE (1980年至2004年6月),Current Contents (1995年至1997年1月),以及相關文章的參考索引。我們聯絡該領域的研究者以確認更多已發表與未發表的研究。


所有已完成的隨機試驗(randomised trial)以比較CEA與藥物治療用於無症狀頸動脈狹窄的病人。




有3個試驗共計5223位病人被納入。在這些試驗當中,全部與手術相關的手術間期中風或死亡的淨增加率是2.9%。以手術間期中風或死亡,或其後的任何中風的初始結果(primary outcome)來說,接受CEA的病人的遭遇比那些受藥物治療的人來得好(相對風險(RR) 0.69, 95% 信賴區間(CI) 0.57 to 0.83)。相似地,對於手術間期的中風或死亡,或其後的同側性中風的預後來說,在手術組也有好處(RR 0.71, 95% CI 0.55 to 0.90)。以任何中風或死亡的預後來說,有一種非顯著性的趨勢是偏向手術組會有較少的事件發生(RR 0.92, 95% CI 0.83 to 1.02)。對於手術間期中風或死亡,或其後的頸動脈區域中風的預後,我們執行了分組分析。CEA顯示在男性比女性來得有利,以及在較年輕的病人比年老的病人來得有利,雖然在年紀的影響方面的資料並非決定性的。評估在不同狹窄等級的病人中,其治療的效果並沒有統計上的顯著差異,但資料並不足夠。





此翻譯計畫由臺灣國家衛生研究院(National Health Research Institutes, Taiwan)統籌。