Rothwell P M, Eliasziw M, Gutnikov S A, Warlow C P, Barnett H J M
Stroke Prevention Research Unit, University Department of Clinical Neurology, Radcliffe Infirmary, Oxford OX2 6HE, UK.
Lancet. 2004 Mar 20;363(9413):915-24. doi: 10.1016/S0140-6736(04)15785-1.
Carotid endarterectomy reduces the risk of stroke in patients with recently symptomatic stenosis. Benefit depends on the degree of stenosis, and we aimed to see whether it might also depend on other clinical and angiographic characteristics, and on the timing of surgery.
We analysed pooled data from the European Carotid Surgery Trial and North American Symptomatic Carotid Endarterectomy Trial. The risk of ipsilateral ischaemic stroke for patients on medical treatment, the perioperative risk of stroke and death, and the overall benefit from surgery were determined in relation to seven predefined and seven post hoc subgroups.
5893 patients with 33000 patient-years of follow-up were analysed. Sex (p=0.003), age (p=0.03), and time from the last symptomatic event to randomisation (p=0.009) modified the effectiveness of surgery. Benefit from surgery was greatest in men, patients aged 75 years or older, and those randomised within 2 weeks after their last ischaemic event, and fell rapidly with increasing delay. For patients with 50% or higher stenosis, the number of patients needed to undergo surgery (ie, number needed to treat) to prevent one ipsilateral stroke in 5 years was nine for men versus 36 for women, five for age 75 years or older versus 18 for younger than 65 years, and five for those randomised within 2 weeks after their last ischaemic event, versus 125 for patients randomised after more than 12 weeks. These results were consistent across the individual trials.
Benefit from endarterectomy depends not only on the degree of carotid stenosis, but also on several other clinical characteristics such as delay to surgery after the presenting event. Ideally, the procedure should be done within 2 weeks of the patient's last symptoms.
颈动脉内膜切除术可降低近期有症状性狭窄患者的中风风险。获益程度取决于狭窄程度，我们旨在探究其是否还取决于其他临床和血管造影特征以及手术时机。
我们分析了欧洲颈动脉外科试验和北美有症状颈动脉内膜切除术试验的汇总数据。针对七个预先定义的亚组和七个事后分析的亚组，确定了接受药物治疗患者的同侧缺血性中风风险、围手术期中风和死亡风险以及手术的总体获益情况。
对5893例患者进行了分析，随访时间达33000患者年。性别（p = 0.003）、年龄（p = 0.03）以及从上一次有症状事件至随机分组的时间（p = 0.009）会改变手术效果。手术获益在男性、75岁及以上患者以及在上一次缺血事件后2周内随机分组的患者中最大，且随着时间延迟迅速下降。对于狭窄程度为50%或更高的患者，在5年内预防一例同侧中风所需接受手术的患者数量（即需治疗人数），男性为9例，女性为36例；75岁及以上患者为5例，65岁以下患者为18例；在上一次缺血事件后2周内随机分组的患者为5例，随机分组时间超过12周的患者为125例。这些结果在各个试验中是一致的。
内膜切除术的获益不仅取决于颈动脉狭窄程度，还取决于其他一些临床特征，如发病事件后至手术的延迟时间。理想情况下，该手术应在患者出现最后症状后的2周内进行。
