Eversion versus conventional carotid endarterectomy for preventing stroke

 

Abstract

Background

Carotid endarterectomy (CEA) is conventionally undertaken by a longitudinal arteriotomy. Eversion CEA, which employs a transverse arteriotomy and reimplantation of the carotid artery, is reported to be associated with low perioperative stroke and restenosis rates but an increased risk of complications associated with a distal intimal flap.

Objectives

To determine whether eversion CEA was safe and more effective than conventional CEA. The null-hypothesis was that there was no difference between the eversion and the conventional CEA techniques (performed either with primary closure or patch angioplasty).

Search methods

We searched the Cochrane Stroke Group Trials Register (last searched July 2002), the Cochrane Central Register of Controlled Trials (The Cochrane Library 2002, Issue 4), MEDLINE (1966 to December 2002) and EMBASE (1980 to December 2002). In addition, eight surgical journals were handsearched and researchers were contacted to identify additional published and unpublished studies.

Selection criteria

All randomised trials comparing eversion to conventional techniques in patients undergoing carotid endarterectomy were examined in this review. Outcomes were stroke and death, carotid restenosis/occlusion, and local complications.

Data collection and analysis

Data were extracted independently by two reviewers to assess eligibility and describe trial characteristics, and by one reviewer for meta-analyses. When possible, unpublished data were obtained from investigators.

Main results

Five trials were included for a total of 2465 patients and 2589 arteries. Three trials included bilateral carotid endarterectomies. In one trial, arteries rather than patients were randomised so that it was not clear how many patients had been randomised in each group, therefore, information on the risk of stroke and death from this study were considered in a separate analysis. There were no significant differences in the rate of perioperative stroke and/or death (1.7% versus 2.6%, odds ratio (OR) 0.44, 95% confidence interval (CI) 0.10 to 1.82) and stroke during follow up (1.4% versus 1.7%, Peto OR 0.84, 95% CI 0.43 to 1.64) between eversion and conventional CEA techniques. Eversion CEA was associated with a significantly lower rate of restenosis > 50% during follow up (2.5% versus 5.2%, Peto OR 0.48, 95% CI 0.32 to 0.72). However, there was no evidence that the eversion technique for CEA was associated with a lower rate of neurological events when compared to conventional CEA. There were no statistically significant differences in local complications between the eversion and conventional group. No data were available to define the cost-benefit of eversion CEA technique.

Authors' conclusions

Eversion CEA may be associated with low risk of arterial occlusion and restenosis. However, numbers are too small to definitively assess benefits or harms. Reduced restenosis rates did not appear to be associated with clinical benefit in terms of reduced stroke risk, either perioperatively or later. Until further evidence is available, the choice of the CEA technique should depend on the experience and familiarity of the individual surgeon.

 

Plain language summary

Eversion versus conventional carotid endarterectomy for preventing stroke

There is not enough evidence to decide the best way to do the operation of carotid endarterectomy (CEA) to prevent stroke. The carotid artery is one of the main arteries in the neck supplying blood to the brain. A blockage in the artery can cause a stroke (a sudden catastrophe in the brain either because an artery to the brain blocks, or because an artery in or on the brain ruptures and bleeds). CEA involves two different methods to clear the artery. This is done by either eversion (oblique division of the internal carotid artery at its origin, removing the blockage through this access and reimplantation (re-joining) of the vessel at the same original level) or conventional CEA (longitudinal opening of the artery followed by removal of the blockage and suture with or without an enlargement patch). The review found that there was not enough evidence to show either the benefits or adverse effects of these two methods. Eversion CEA may lower the risk of restenosis (renarrowing) of the artery but more research is needed.

 

摘要

背景

外翻式與傳統頸動脈內膜切除術對於預防中風的比較

頸動脈內膜切除術(CEA)傳統上是經由縱向動脈切開來進行。外翻式CEA，利用橫向動脈切開與頸動脈的再移植，被報告說有較低的手術間期中風以及再狹窄的機率，但是因遠端內膜瓣產生的併發症其風險則較高。

目標

此篇回顧論文的目的是確定外翻式CEA是否安全且比傳統CEA更為有效。此中性假說(nullhypothesis)是外翻式與傳統CEA技術(藉由單純縫合抑或血管補片來進行)之間並沒有差別。

搜尋策略

檢閱者們搜尋Cochrane Stroke Group Trials Register(搜尋至2002年7月)，Cochrane Central Register of Controlled Trials (The Cochrane Library 2002, Issue 4)，MEDLINE(1966 – 2002年12月)以及EMBASE(1980 – 2002年12月)。此外，他們並查閱8種外科期刊以及聯絡研究者以確認更多已發表或未發表的研究。

選擇標準

這篇回顧論文檢視了在接受頸動脈內膜切除術的病人中，所有比較外翻式與傳統技術的隨機試驗(randomised trial)。預後是中風與死亡、頸動脈再狹窄/阻塞，以及局部的併發症。

資料收集與分析

兩位檢閱者各自篩選資料以評估試驗資格並描述試驗特性，且由一位檢閱者做統合分析(metaanalysis)。他們藉由討論來消除歧見。如果可能的話，也從研究者那邊獲取未發表的資料。

主要結論

共5個試驗囊括2465位病人與2589條動脈血管被納入。有3個試驗包含了雙側的頸動脈內膜切除術。在其中一個試驗，被隨機分派的是動脈血管而非病人，所以無法確知每一組中被分派了多少病人，因此在這個試驗中關於中風與死亡風險的資訊被用單獨的分析來考慮。在手術間期的中風及/或死亡率(1.7% vs 2.6%, 勝算比[OR] 0.44, 95% 信賴區間[CI] 0.10 – 1.82)以及追蹤期內的中風率(1.4% vs 1.7%, Peto OR: 0.84, 95% CI: 0.43 – 1.64)，在外翻式與傳統CEA技術之間並沒有顯著的差異。外翻式CEA在追蹤期內大於50%再狹窄的比率顯著地較低(2.5% vs 5.2%, Peto OR: 0.48, 95% CI: 0.32 −0.72)。然而，並沒有證據顯示外翻式CEA的技術比起比起傳統CEA在神經學事件上有較低的發生率。局部的併發症在外翻與傳統兩組間並沒有統計學上顯著的差異。沒有資料可以用來判定外翻式CEA技術的成本效益。

作者結論

外翻式CEA可能有較低的動脈阻塞與再狹窄的風險。然而，因為數目太小所以無法確定評估利益與傷害。降低再狹窄率無法顯示與臨床上的好處相關 – 亦即降低中風的風險，在手術間期或是之後。直到能取得更多證據之前，CEA技術的選擇應該依每一位執刀者的經驗跟熟悉度而定。

翻譯人

本摘要由奇美醫院陳軾正翻譯。

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

總結

沒有足夠的證據用以決定頸動脈內膜切除術(CEA)的最佳方式以避免中風。 頸動脈是在頸部供給腦部血流的主要動脈之一。這條動脈內的阻塞會造成中風(因為到腦部的動脈阻斷抑或是腦中或腦上面的動脈破裂出血而導致的突發性不幸事件)。有兩種CEA的方法可以清除動脈(阻塞)。一者是外翻式(在內頸動脈起源處斜向切開，由此途徑移除阻塞物並在同樣的起源位置重新植入(重新接合)這條血管)抑或是傳統式CEA (將動脈垂直打開，接著移除阻塞物並使用或不使用擴大補片加以縫合)。這篇回顧發現並沒有充分的證據以顯示此兩種方式的益處或是不良影響。外翻式CEA可能降低動脈再狹窄(再窄化)的風險，但更多的研究是被需要的。