BACKGROUND Endovascular treatment (EVT) is an established procedure in patients with acute ischemic stroke due to occlusion of the proximal M1-segment of middle cerebral artery. The assessment of distal thrombectomy in daily clinical routine has not yet been sufficiently evaluated. METHODS Patients with M2-segment-occlusions treated by EVT in the local department (January 2012-December 2017) were included (n = 57, mean National-Institutes-of-Health-Stroke-Scale of 11, range 0-20). Patients were grouped according to localization of M2-occlusion (Cohort A (n = 14): central region only, B (n = 24): central region and involvement of frontal vessels, C (n = 19): parietal, occipital, and/or temporal vessels). Differences in proximal (M2-trunk, n = 34) and distal (M2-branches, n = 23) occlusions were also examined. Reperfusion (Thrombolysis-In-Cerebral-Infarction (TICI)), early clinical outcome at discharge (modified Rankin Scale (mRS)), and complications (hemorrhage, new emboli) were noted. RESULT Successful reperfusion (TICI2b-3) was found in 49 patients (86.0%). Favorable early clinical outcome (mRS0-2) was achieved in n = 19 (37.7%). Compared to admission, mRS at discharge improved significantly (median (admission) 5 vs. median (discharge) 4, p < 0.001). Early clinical outcome was more favorable in patients with better reperfusion (TICI2b-3: mean mRS 3 ± 1.7 vs. TICI0-2a: mean mRS 4.4 ± 1.4, p = 0.037). Six (10.5%) patients suffered from symptomatic intracranial hemorrhage during treatment or hospitalization. Four patients died (7.0%). No significant differences in favorable clinical outcome (mRS ≤ 2: Cohort A 42.9%, B 50.0%, C 16.7%, p = 0.4; χ2-test) or periinterventional complications were found with regard to vessel involvement. CONCLUSION EVT in patients with acute M2-occlusion is safe and leads to a significant clinical improvement at discharge. No significant differences in clinical outcome or complications were found with regard to the localization of the M2-occlusion.

中文翻译：

---

机械性血栓切除术治疗急性脑中动脉M2段闭塞。

背景技术血管内治疗（EVT）是由于大脑中动脉近端M1段闭塞而导致的急性缺血性卒中患者的既定方法。日常临床常规中远端血栓切除术的评估尚未得到充分评估。方法纳入当地部门（2012年1月至2017年12月）接受EVT治疗的M2段闭塞患者（n = 57，平均美国国家卫生研究院卒中量表为11，范围为0-20）。根据M2闭塞的位置将患者分组（队列A（n = 14）：仅中央区域，B（n = 24）：中央区域和额叶受累，C（n = 19）：顶叶，枕叶和/或颞血管）。还检查了近端（M2躯干，n = 34）和远端（M2分支，n = 23）阻塞的差异。记录了再灌注（溶栓，脑梗塞（TICI）），出院时的早期临床结局（改良的兰金评分（mRS））和并发症（出血，新栓塞）。结果在49例患者中发现了成功的再灌注（TICI2b-3）（86.0％）。在n = 19（37.7％）时达到了良好的早期临床结果（mRS0-2）。与入院相比，出院时的mRS显着改善（中位（入院）5 vs中位（出院）4，p <0.001）。对于再灌注更好的患者，早期临床结局更为有利（TICI2b-3：平均mRS 3±1.7与TICI0-2a：平均mRS 4.4±1.4，p = 0.037）。在治疗或住院期间，六名（10.5％）的患者出现了症状性颅内出血。4例患者死亡（7.0％）。良好的临床结果无显着差异（mRS≤2：队列A 42.9％，B 50.0％，C 16.7％，p = 0.4；进行了χ2检验）或介入血管周围并发症。结论急性M2闭塞患者的EVT是安全的，可在出院时带来显着的临床改善。关于M2闭塞的定位，在临床结果或并发症方面未发现显着差异。