Safian Robert D
Center for Innovation and Research in Cardiovascular Diseases, Department of Cardiovascular Medicine, Beaumont Health, Royal Oak, MI.
Prog Cardiovasc Dis. 2017 May-Jun;59(6):591-600. doi: 10.1016/j.pcad.2017.04.006. Epub 2017 May 3.
In patients with carotid stenosis, the most common cause of stroke is atheroembolization, and the risk is strongly related to stenosis severity and symptomatic status (stroke or transient ischemic attack within 6months). Carotid revascularization by carotid endarterectomy (CEA) or carotid artery stenting (CAS) results in plaque "passivation" by lumen enlargement, plaque removal, or plaque coverage with subsequent endothelialization. While there is considerable circumstantial evidence linking a decrease in the risk of stroke to the use of "optimal medical therapy (OMT)", the components of OMT have not been defined, and such therapy has not been rigorously evaluated in any randomized clinical trial (RCT) compared with revascularization. Studies of other vascular patients suggest that statins decrease the risk of stroke by anti-inflammatory effects, rather than cholesterol reduction. The Carotid Revascularization Endarterectomy versus Stent Trial (CREST-2) is currently randomizing standard-risk patients with asymptomatic severe carotid stenosis to OMT alone versus OMT plus CEA or CAS, but results are not expected until 2020. In the meantime, data from several "landmark" trials of CEA versus aspirin demonstrated 45-65% reduction in the 5-year risk of stroke after CEA. Several RCTs demonstrate superiority of CAS over CEA in high-risk patients (those at high-risk for CEA), and equivalence of CAS and CEA in standard-risk patients (those at acceptable risk for CEA). Compared with CEA, CAS is associated with significantly less periprocedural myocardial infarction, cranial nerve injury, and neurological injury (cranial nerve injury plus stroke); higher risk of minor stroke; and similar risk of long-term stroke. Features that increase the risk of CAS include complex aortic arch and carotid anatomy, and features that increase the risk of CEA include severe underlying cardiopulmonary disease and hostile neck anatomy; age>80years, especially those with baseline cognitive impairment, are at higher risk for stroke after CEA and CAS.
在颈动脉狭窄患者中，中风的最常见病因是动脉粥样硬化栓塞，其风险与狭窄严重程度及症状状态（6个月内发生中风或短暂性脑缺血发作）密切相关。通过颈动脉内膜切除术（CEA）或颈动脉支架置入术（CAS）进行颈动脉血运重建，可通过管腔扩大、斑块清除或斑块覆盖并随后内皮化实现斑块“钝化”。虽然有大量间接证据表明使用“优化药物治疗（OMT）”可降低中风风险，但OMT的组成部分尚未明确，且与血运重建相比，这种治疗方法尚未在任何随机临床试验（RCT）中得到严格评估。对其他血管疾病患者的研究表明，他汀类药物通过抗炎作用而非降低胆固醇来降低中风风险。颈动脉血运重建内膜切除术与支架试验（CREST-2）目前正在将无症状重度颈动脉狭窄的标准风险患者随机分为单纯OMT组与OMT加CEA或CAS组，但预计到2020年才能得出结果。与此同时，多项CEA与阿司匹林对比的“里程碑”试验数据表明，CEA后5年中风风险降低了45%-65%。多项RCT表明，在高危患者（CEA高风险患者）中，CAS优于CEA；在标准风险患者（CEA可接受风险患者）中，CAS与CEA等效。与CEA相比，CAS围手术期心肌梗死、颅神经损伤和神经损伤（颅神经损伤加中风）明显更少；轻微中风风险更高；长期中风风险相似。增加CAS风险的特征包括复杂的主动脉弓和颈动脉解剖结构，增加CEA风险的特征包括严重的基础心肺疾病和颈部解剖结构复杂；年龄>80岁，尤其是那些有基线认知障碍的患者，CEA和CAS后中风风险更高。
