エビデンスに基づく頸部頸動脈狭窄症の治療戦略

Treatment for Cervical Carotid Artery Stenosis Using Evidenced-based Medicine

はじめに

　頸部頸動脈狭窄症に対する治療の基本はリスクファクターの管理と抗血栓療法であり，一定の条件が満たされれば頸動脈内膜剝離術（carotid endarterectomy：CEA）あるいは頸動脈ステント術（carotid artery stenting：CAS）が適応となる。その適応に関しては，ランダム化比較試験（randomized controlled study）である大規模研究が数多くなされている。本稿では，各大規模研究について解説し，これらに基づいた治療戦略につき述べる。

Abstract

　While cervical carotid stenosis should be essentially treated with anti-thrombotic drugs,carotid endarterectomy (CEA) or carotid artery stenting (CAS) may be performed for such lesions when definite criteria are met.　These criteria have been determined through several large controlled randomized trials.　The benefit of CEA has been established by NASCET,ECST,ACAS,and ACST.　The SAPPHIRE trial showed the non-inferiority of CAS compared to CEA in patients with high-risk factors for CEA.　However,SPACE,EVA-3S,and ICSS failed to show this non-inferiority in patients without high risk factors for CEA.　CREST,the most recent trial,has demonstrated that CAS and CEA are equally effective.　In conclusion,CEA is the treatment of choice for patients with severe asymptomatic or symptomatic carotid artery stenosis.　CAS should be performed for patients with severe carotid artery stenosis only when they have high-risk factors for CEA.