Department of Neurology and Stroke Unit, University Hospital Basel, Basel, Switzerland.
Lancet Neurol. 2010 Apr;9(4):353-62. doi: 10.1016/S1474-4422(10)70057-0. Epub 2010 Feb 25.
The International Carotid Stenting Study (ICSS) of stenting and endarterectomy for symptomatic carotid stenosis found a higher incidence of stroke within 30 days of stenting compared with endarterectomy. We aimed to compare the rate of ischaemic brain injury detectable on MRI between the two groups.
Patients with recently symptomatic carotid artery stenosis enrolled in ICSS were randomly assigned in a 1:1 ratio to receive carotid artery stenting or endarterectomy. Of 50 centres in ICSS, seven took part in the MRI substudy. The protocol specified that MRI was done 1-7 days before treatment, 1-3 days after treatment (post-treatment scan), and 27-33 days after treatment. Scans were analysed by two or three investigators who were masked to treatment. The primary endpoint was the presence of at least one new ischaemic brain lesion on diffusion-weighted imaging (DWI) on the post-treatment scan. Analysis was per protocol. This is a substudy of a registered trial, ISRCTN 25337470.
231 patients (124 in the stenting group and 107 in the endarterectomy group) had MRI before and after treatment. 62 (50%) of 124 patients in the stenting group and 18 (17%) of 107 patients in the endarterectomy group had at least one new DWI lesion detected on post-treatment scans done a median of 1 day after treatment (adjusted odds ratio [OR] 5.21, 95% CI 2.78-9.79; p<0.0001). At 1 month, there were changes on fluid-attenuated inversion recovery sequences in 28 (33%) of 86 patients in the stenting group and six (8%) of 75 in the endarterectomy group (adjusted OR 5.93, 95% CI 2.25-15.62; p=0.0003). In patients treated at a centre with a policy of using cerebral protection devices, 37 (73%) of 51 in the stenting group and eight (17%) of 46 in the endarterectomy group had at least one new DWI lesion on post-treatment scans (adjusted OR 12.20, 95% CI 4.53-32.84), whereas in those treated at a centre with a policy of unprotected stenting, 25 (34%) of 73 patients in the stenting group and ten (16%) of 61 in the endarterectomy group had new lesions on DWI (adjusted OR 2.70, 1.16-6.24; interaction p=0.019).
About three times more patients in the stenting group than in the endarterectomy group had new ischaemic lesions on DWI on post-treatment scans. The difference in clinical stroke risk in ICSS is therefore unlikely to have been caused by ascertainment bias. Protection devices did not seem to be effective in preventing cerebral ischaemia during stenting. DWI might serve as a surrogate outcome measure in future trials of carotid interventions.
UK Medical Research Council, the Stroke Association, Sanofi-Synthélabo, European Union, Netherlands Heart Foundation, and Mach-Gaensslen Foundation.
国际颈动脉支架研究(ICSS)发现,与颈动脉内膜切除术相比,支架置入术治疗症状性颈动脉狭窄患者在术后 30 天内发生中风的风险更高。我们旨在比较两组之间可通过 MRI 检测到的缺血性脑损伤的发生率。
ICSS 中近期出现症状性颈动脉狭窄的患者被随机分为 1:1 比例,分别接受颈动脉支架置入术或内膜切除术。在 50 个参与 ICSS 的中心中,有 7 个参与了 MRI 子研究。方案规定 MRI 在治疗前 1-7 天、治疗后 1-3 天(治疗后扫描)以及治疗后 27-33 天进行。由两名或三名研究人员对扫描进行分析,这些人员对治疗情况进行了盲法。主要终点是在治疗后扫描的弥散加权成像(DWI)上存在至少一个新的缺血性脑病变。分析是按照方案进行的。这是一项已注册试验(ISRCTN25337470)的子研究。
231 名患者(支架组 124 名,内膜切除术组 107 名)在治疗前后进行了 MRI。支架组 124 名患者中有 62 名(50%)和内膜切除术组 107 名患者中有 18 名(17%)在治疗后中位数为 1 天的扫描中发现至少有一个新的 DWI 病变(调整后的优势比 [OR] 5.21,95%CI 2.78-9.79;p<0.0001)。在 1 个月时,支架组 86 名患者中有 28 名(33%)和内膜切除术组 75 名患者中有 6 名(8%)的液体衰减反转恢复序列发生了变化(调整后的 OR 5.93,95%CI 2.25-15.62;p=0.0003)。在支架治疗中心采用脑保护装置治疗的患者中,支架组 51 名患者中有 37 名(73%)和内膜切除术组 46 名患者中有 8 名(17%)在治疗后扫描上存在至少一个新的 DWI 病变(调整后的 OR 12.20,95%CI 4.53-32.84),而在未采用脑保护装置治疗的支架治疗中心,支架组 73 名患者中有 25 名(34%)和内膜切除术组 61 名患者中有 10 名(16%)在 DWI 上存在新病变(调整后的 OR 2.70,1.16-6.24;交互作用 p=0.019)。
支架组患者中有新的 DWI 缺血性病变的患者约为内膜切除术组的三倍。因此,ICSS 中临床中风风险的差异不太可能是由于检测偏倚引起的。保护装置在支架置入术中似乎不能有效预防脑缺血。DWI 可能成为未来颈动脉介入治疗试验的替代终点。
英国医学研究理事会、中风协会、赛诺菲-安万特、欧盟、荷兰心脏基金会和 Mach-Gaensslen 基金会。