The Claw Sign: An angiographic Predictor of Recanalization After Mechanical Thrombectomy for Cerebral Large Vessel Occlusion

Background: Mechanical thrombectomy undoubtedly improves functional outcomes for patients with acute ischemic stroke. Although we have observed occlusion sites that protrude proximally into the vessel on angiography, termed the “claw sign,” we have been unable to state its clinical significance. In this study, we aimed to determine whether the presence of a claw sign was related to recanalization success after mechanical thrombectomy. Materials and Methods: We retrospectively included 73 consecutive patients treated for acute cerebral large vessel occlusion by mechanical thrombectomy between January 2014 and December 2017. The angiographic claw sign was defined as a thrombus that protruded proximally by more than half the diameter of the parent artery. Claw sign positivity, clinical and etiological features, and outcomes were compared between groups with and without recanalization. Results: The claw sign was observed in 29 of 73 (40%) patients and was positive significantly more frequently in those with recanalization (50.0%) than in those without recanalization (5.9%) (P < .01). By multivariate analysis, the claw sign was the only pretreatment parameter to predict successful recanalization (odds ratio, 12.50; 95% confidence interval, 1.50-103.00; P = .019). Conclusions: The presence of the claw sign might predict successful recanalization in patients undergoing mechanical thrombectomy for large vessel occlusion.     

4～6h时间窗内急性脑梗死患者行机械开通的疗效分析

目的评价发病4~6h机械开通治疗急性脑梗死的疗效及安全性。方法对2015-06—2016-12在我科住院的发病4~6h时间窗内的187例急性脑梗死患者进行回顾性分析,患者全部行脑血管造影检查明确病因,对大血管闭塞患者行单纯支架取栓治疗,统计血管再通情况及分析临床疗效。结果介入治疗术后M2段闭塞共17例(12例再通),M1段闭塞共58例(52例再通),颈内动脉末端闭塞(T型)共9例(4例再通),床突段闭塞共7例(1例再通),颈内动脉大负荷量血栓共15例(10例再通),椎基底动脉闭塞共28例(24例再通)。M2段闭塞患者治疗1周以后病情较术前明显好转(P0.05),M1段闭塞的患者在术后1d就出现明显好转(P0.01),椎基底动脉闭塞的患者术后第1天就出现明显好转(P0.05)。1个月后mRS 1~3分的患者中M2段闭塞占88%,M1段闭塞占60%,颈内动脉末端闭塞(T型)占11%,床突段闭塞占14%,颈内动脉大负荷量血栓占7%,椎基底动脉闭塞占39%。结论发病4~6h时间窗内行机械取栓血管再通治疗安全有效,大部分患者的闭塞动脉能及时再通,临床疗效显著。     

Mechanical Thrombectomy of the Middle Cerebral Artery – Neither Segment nor Diameter Matter

ObjectivesThe aim of this study was to explore the role of the vessel diameter at the site of middle cerebral artery (MCA) occlusion in acute ischemic stroke patients who underwent mechanical thrombectomy (MT) regarding technical aspects, safety, and clinical outcomes.MethodsIn a retrospective analysis, cerebral artery diameters were measured using digital subtraction angiography in patients with isolated M1 or M2 occlusions undergoing MT. Associations between occluded vessel, occlusion diameter and outcomes were analyzed using logistic regression models adjusting for prespecified prognostic factors.Results168 patients with M1 occlusions and 98 patients with M2 occlusions who underwent MT were included. Mean vessel diameters at M1 and M2 occlusion sites differed significantly (2.15 +/− .36 1.55 +/− .38, P < .001). Vessel diameters at the occlusion site and occluded vessel segment did not predict good functional outcome (aOR 1.2 CI .28-5.26, P = .659; aOR .84 CI .35-2.03, P = .841) or mortality (aOR .21 CI .04-1.01, P = .215; aOR 1.36 CI .55-3.37, P = .676). No significant differences in successful recanalization, good functional outcome, mortality, procedural complications, and intracranial hemorrhages between M1 and M2 occlusions was observed.ConclusionsIn this study no significant effect of the MCA vessel diameter on successful recanalization, good functional outcome, or mortality of acute ischemic stroke patients treated with MT could be detected. However, these findings need to be confirmed in further studies.     

The Effectiveness of Additional Treatment Modalities after the Failure of Recanalization by Thrombectomy Alone in Acute Vertebrobasilar Arterial Occlusion

Objective

Acute vertebrobasilar artery occlusion (AVBAO) is a devastating disease with a high mortality rate. One of the most important factors affecting favorable clinical outcome is early recanalization. Mechanical thrombectomy is an emerging treatment strategy for achieving a high recanalization rates. However, thrombectomy alone can be insufficient to complete recanalization, especially for acute stroke involving large artery atheromatous disease. The purpose of this study is to investigate the safety and efficacy of mechanical thrombectomy in AVBAO.

Methods

Fourteen consecutive patients with AVBAO were treated with mechanical thrombectomy. Additional multimodal treatments were intra-arterial (IA) thrombolysis, balloon angioplasty, or permanent stent placement. Recanalization by thrombectomy alone and multimodal treatments were assessed by the Thrombolysis in Cerebral Infarction (TICI) score. Clinical outcome was determined using the National Institutes of Health Stroke Scale (NIHSS) at 7 days and the modified Rankin Scale (mRS) at 3 months.

Results

Thrombectomy alone and multimodal treatments were performed in 10 patients (71.4%) and 4 patients (28.6%), respectively. Successful recanalization (TICI 2b-3) was achieved in 11 (78.6%). Among these 11 patients, 3 (27.3%) underwent multimodal treatment due to underlying atherosclerotic stenosis. Ten (71.4%) of the 14 showed NIHSS score improvement of >10. Overall mortality was 3 (21.4%) of 14.

Conclusion

We suggest that mechanical thrombectomy is safe and effective for improving recanalization rates in AVBAO, with low complication rates. Also, in carefully selected patients after the failure of recanalization by thrombectomy alone, additional multimodal treatment such as IA thrombolysis, balloons, or stents can be needed to achieve successful recanalization.     

Impaired Cerebrovascular Autoregulation in Large Vessel Occlusive Stroke after Successful Mechanical Thrombectomy: A Prospective Cohort Study

Introduction: Successful thrombectomy improves morbidity and mortality after stroke. The present prospective, observational cohort study investigated a potential correlation between the successful restoration of tissue perfusion by mechanical thrombectomy and intact cerebrovascular autoregulation (CA). Objective: Status of CA in patients with large vessel occlusive stroke after thrombectomy. Methods: After thrombectomy CA was measured using transcranial Doppler ultrasound. For this purpose a moving correlation index (Mxa) based on spontaneous arterial blood pressure fluctuations and corresponding cerebral blood flow velocity changes was calculated. CA impairment was defined by Mxa values more than .3. Results: Twenty patients with an acute occlusion of the middle cerebral artery or distal internal carotid artery were included. A successful recanalization of the occluded vessel via interventional thrombectomy was achieved in 10 of these patients (successful recanalization group), while in 10 patients mechanical recanalization failed or could not be applied (no recanalization group). Mean Mxa at stroke side was .58 ± .21 Table 2a in patients with successful intervention. At the unaffected hemisphere Mxa was .50 ± .20 Table 2a in successful recanalization group and .45 ± .24 Table 2b in no recanalization group without statistically significant differences. Based on the previously defined Mxa cut off more than .3, CA impairment was observable in all successful recanalized patients and in 8 of 10 patients with unsuccessful interventional treatment. Conclusions: These results suggest that brain perfusion may be affected due to impaired CA even after successful mechanical thrombectomy. Therefore, a tight blood pressure management is of great importance in post-thrombectomy stroke treatment to avoid cerebral hypo- and hyperperfusion.     

Predictors of Futile Recanalization After Endovascular Treatment in Patients with Acute Ischemic Stroke in a Multicenter Registry Study

BackgroundFutile recanalization, defined as the early recanalization of an occluded artery failing to improve neurological outcome, remains a persistent concern in the endovascular treatment of acute ischemic stroke. We investigated the occurrence and predictors of futile recanalization after endovascular treatment in a nationwide multicenter stroke registry study.MethodsThe subjects consisted of eligible patients from the Acute Ischemic Stroke Cooperation Group of Endovascular Treatment registry study (2015–2017). Subjects with acute anterior large vessel occlusion who achieved successful angiographic recanalization (defined as modified Thrombolysis in Cerebral Infarction grades 2b or 3) by endovascular treatment were dichotomized into the futile-recanalization group (with a modified Rankin Scale score of 3–6) and the favorable-recanalization group (with a modified Rankin Scale score of 0–2) according to 90-day functional independence. Logistic regression analysis was performed to investigate predictors of futile recanalization.ResultsFutile recanalization was observed in 200 (49.6%) out of 403 patients. On multivariate analysis, older age (>74 vs. ≤74; odds ratio (OR), 2.41; 95% confidence interval (CI), 1.31–4.44; P=0.005), high baseline National Institutes of Health Stroke Scale score (>21 vs. ≤13; OR, 2.52; 95% CI, 1.21–5.28; P=0.014), delayed puncture to recanalization time (>80 vs. ≤80 min; OR, 2.75; 95% CI, 1.67–4.51; P=0.000), and the use of general anesthesia (OR, 1.90; 95% CI, 1.15–3.14; P=0.012) were positively associated with futile recanalization after mechanical thrombectomy.ConclusionsThe incidence of futile recanalization is common following endovascular treatment among Asian patients with anterior circulation occlusion. Advanced age, higher baseline National Institutes of Health Stroke Scale score, delayed puncture to reperfusion, and the use of general anesthesia are associated with lower functional independence 90 days post-treatment despite successful recanalization.     

急性大脑中动脉闭塞机械取栓治疗的观察性研究

目的探讨大脑中动脉急性闭塞后行血管内机械取栓的优化治疗方式及疗效。方法以行血管内机械取栓的大脑中动脉闭塞的急性缺血性卒中患者为研究对象,回顾性分析其责任病灶特点、血管内治疗方式、血管开通状况及术后神经功能改善状况。结果连续纳入2014年1月-2016年8月期间于中山市人民医院脑血管介入科行急性大脑中动脉闭塞机械取栓的患者77例,其中M1段闭塞52例(右侧27例,左侧25例),上干闭塞15例,下干闭塞10例。取栓后Solitaire支架释放在狭窄部位17例,合并大脑中动脉严重狭窄应用Gateway球囊扩张6例,局部动脉给予溶栓药物3例。经血管内治疗后,77例大脑中动脉闭塞全部成功开通。术后再灌注出血6例(7.79%),取栓术后因急性脑肿胀行去骨瓣减压术5例(6.49%),术后90 d患者预后良好[改良Rankin量表(modified Rankin Scale,m RS)评分2分]48例(62.34%)。结论大脑中动脉急性闭塞行Solitaire支架急诊取栓可获得满意的再通率及3个月良好预后。     

大脑中动脉M2段闭塞血管再通研究进展

与颈内动脉和大脑中动脉M1段相比，大脑中动脉M2段更加纤细、迂曲，其急性闭塞后血 管再通治疗包括静脉溶栓、动脉溶栓及机械取栓，但血管内治疗的安全性和有效性仍有争议。目前 的研究显示，动脉溶栓和机械取栓的血管再通率高于单纯的静脉溶栓，但这3种治疗方法对90 d预 后的影响差异不大。另外，因研究相对较少，目前治疗方法对出血转化的影响尚无定论。     

Endovascular treatment of acute carotid atherosclerotic tandem occlusions: Predictors of clinical outcomes as technical aspects and location of tandem occlusions

BackgroundWe aimed to analyze angiographic and clinical outcomes according to the sequence of treatment (antegrade versus retrograde) in patients with acute ischemic stroke caused by tandem extracranial cervical carotid and intracranial large vessel occlusion.Materials and methodsAll eligible tandem occlusion patients from April 2012 to March 2019 undergoing carotid artery stenting (CAS) simultaneously with intracranial endovascular thrombectomy (EVT) were retrospectively reviewed. After dividing into 2 groups according to the treatment sequence for tandem lesions (antegrade, CAS first; retrograde, intracranial EVT first), baseline data, immediate angiographic results, and clinical outcome for eligible patients were analyzed and compared. In addition, the same analysis was performed after dividing into 3 groups based on the location of intracranial lesions (T-zone, M1, M2).ResultsA total of 76 patients with a tandem occlusion (mean age, 71.7 y± 11.1) were treated with CAS and intracranial EVT. The rate of successful recanalization (TICI 2BC) was 83% (63/76), and favorable functional outcome was achieved in 49% (37/76). When comparing antegrade and retrograde methods, there were no differences in baseline data and angiographic or clinical outcomes. Favorable functional outcome was significantly higher in the M2 occlusion group (P=0.011). In multivariate analysis, baseline NIHSS <15, age <80, and M2 occlusion were revealed as independent predictors of favorable outcome.ConclusionDifferent endovascular sequences for tandem extracranial cervical carotid and intracranial large vessel occlusion do not affect angiographic or functional outcomes. Intracranial M2 occlusion, age, and baseline NIHSS were independent predictors of good clinical outcome at 3 months.     

Leukoaraiosis is a predictor of futile recanalization in acute ischemic stroke

Futile recanalization occurs when successful recanalization fails to improve clinical outcome in acute ischemic stroke patients. Predictors of futile recanalization are still debated and may help in selecting patients for reperfusion strategies. We aim to determine whether leukoaraiosis may be useful in predicting futile recanalization in acute ischemic stroke patients treated by endovascular mechanical thrombectomy. We included in the analysis patients with acute ischemic stroke due to anterior circulation large vessel occlusion undergoing endovascular mechanical thrombectomy obtaining complete vessel recanalization. Demographics, vascular risk factors, baseline National Institutes of Health Stroke Scale score, time from symptoms onset to recanalization, Alberta Stroke Program Early CT Score, and leukoaraiosis graded on a 4-point van Swieten scale were collected. We dichotomized patients into those with moderate–severe leukoaraiosis (2–4) versus those with absent-slight leukoaraiosis (0, 1). Outcome measures were symptomatic intracranial hemorrhage, and modified Rankin scale score at 90 days. The relationships among radiological parameters and clinical data with outcome measures were studied with univariate and multivariable analyses. Sixty-eight patients were identified. Recanalization was futile in 32.4% of cases. On multivariable logistic regression analysis, the presence of moderate–severe LA was independent predictors of FR (P = 0.01). Furthermore, higher NIHSS score at baseline (P < 0.01) end endovascular mechanical thrombectomy alone treatment (P < 0.01) resulted associated with futile recanalization. Our results showed that the presence of moderate–severe leukoaraiosis is associated with poor outcome in recanalized patients.     

Cardiac Biomarkers Predict Large Vessel Occlusion in Patients with Ischemic Stroke

Background and PurposeCardiac biomarkers may help identify stroke mechanisms and may aid in improving stroke prevention strategies. There is limited data on the association between these biomarkers and acute ischemic stroke (AIS) caused by large vessel occlusion (LVO). We hypothesized that cardiac biomarkers (cardiac troponin and left atrial diameter [LAD]) would be associated with the presence of LVO.MethodsData were abstracted from a single center prospective AIS database over 18 months and included all patients with AIS with CT angiography of the head and neck. The presence of LVO was defined as proximal LVO of the internal carotid artery terminus, middle cerebral artery (M1 or proximal M2), or basilar artery. Univariate analyses and predefined multivariable models were performed to determine the association between cardiac biomarkers (positive troponin [troponin ≥0.1 ng/mL] and LAD on transthoracic echocardiogram) and LVO adjusting for demographic factors (age and sex), risk factors (hypertension, diabetes, hyperlipidemia, history of stroke, congestive heart failure, coronary heart disease, and smoking), and atrial fibrillation (AF).ResultsWe identified 1234 patients admitted with AIS; 886 patients (71.8%) had vascular imaging to detect LVO. Of those with imaging available, 374 patients (42.2%) had LVO and 207 patients (23.4%) underwent thrombectomy. There was an association between positive troponin and LVO after adjusting for age, sex and other risk factors (adjusted OR 1.69 [1.08-2.63], P = .022) and this association persisted after including AF in the model (adjusted OR 1.60 [1.02-2.53], P = 0.043). There was an association between LAD and LVO after adjusting for age, sex, and risk factors (adjusted OR per mm 1.03 [1.01-1.05], P = 0.013) but this association was not present when AF was added to the model (adjusted OR 1.01 [0.99-1.04], P = .346). Sensitivity analyses using thrombectomy as an outcome yielded similar findings.ConclusionsCardiac biomarkers, particularly serum troponin levels, are associated with acute LVO in patients with ischemic stroke. Prospective studies are ongoing to confirm this association and to test whether anticoagulation reduces the risk of recurrent embolism in this patient population.     

A Direct Aspiration First Pass Technique for Vertebra-Basilar Occlusion: A Retrospective Comparison to Stent Retriever

ObjectivesThis study aimed to assess the clinical usefulness of a direct aspiration first pass technique as a first-line strategy for mechanical thrombectomy in posterior circulation.Materials and methodsWe examined 34 consecutive patients treated with mechanical thrombectomy for acute vertebrobasilar artery occlusion. Procedural and clinical outcomes were assessed and compared between patients treated with a direct aspiration first pass technique first-line strategy (ADAPT group) and stent retriever system first-line strategy (stent retriever group).ResultsOverall, successful reperfusion, complete reperfusion, and first-pass effects were achieved in 94.1%, 61.8%, and 50% of patients with acute ischemic stroke in vertebra-basilar artery occlusion treated with mechanical thrombectomy, respectively. The ADAPT group required a significantly shorter procedural time (p=.015) and fewer attempts (p=.0498) to achieve successful recanalization than the stent retriever group. The ADAPT group also tended to show better recanalization rates and first-pass effects than the stent retriever group. The rates of favorable outcomes seemed to be better, although insignificant, in the ADAPT group than in the stent retriever group (52.2% vs. 27.3%, p=.217). However, a significant correlation between the time required for reperfusion and clinical outcome was detected, and this will serve as the rationale for encouraging a direct aspiration first pass technique as a first-line strategy in the acute vertebra-basilar artery.ConclusionsThe a direct aspiration first pass technique first-line strategy for mechanical thrombectomy in posterior circulation may achieve successful recanalization with fewer attempts and shorter durations than the stent retriever first-line strategy.     

Clinical implications of CT hyperdense artery sign in patients with acute middle cerebral artery occlusion in the era of modern mechanical thrombectomy

The clinical implications of the CT hyperdense artery sign have yet to be established in the new era of modern mechanical thrombectomy. This study aimed to investigate prognostic implications of the CT hyperdense middle cerebral artery sign (HMCAS) on treatment outcomes after mechanical thrombectomy for acute MCA occlusions. A retrospective analysis of CT and clinical data from 212 patients with acute MCA occlusions who underwent mechanical thrombectomy was conducted. HMCAS was determined with visual assessment by consensus of two readers. Interobserver agreement was measured. HMCAS was classified into two groups: M1 and M2 HMCAS. Associations between HMCAS and vascular risk factors, stroke etiology, and treatment outcomes were analyzed. Of 212 patients, HMCAS was identified in 118 patients (55.7%). Overall, successful reperfusion was achieved in 82.5% (175/212) and a good outcome in 45.8% (97/212). There was no significant association between HMCAS and treatment outcomes after mechanical thrombectomy, regardless of HMCAS location. Cardioembolism was more frequent in patients with a positive HMCAS (67.8 vs 48.9%, P = 0.005). Large-artery atherosclerosis was more frequent in patients with a negative HMCAS (31.9 vs 12.7%, P = 0.001). Underlying severe MCA stenosis was more frequently observed in patients with a negative HMCAS (25.5 vs 3.4%, P < 0.001). Our study suggests that the prognostic implication of a HMCAS in predicting outcomes after endovascular therapy in patients with acute MCA occlusion may be low in the era of modern mechanical thrombectomy. Negative HMCAS is predictive of in situ thrombotic occlusion due to underlying severe atherosclerotic stenosis in such patients.     

Use of Middle Cerebral Artery Visualization with Coronal Computed Tomography to Access Target Artery in Mechanical Thrombectomy

Background: When introducing a microguidewire into an occluded vessel during mechanical thrombectomy (MT), visual information on the vessel course distal to the occluded site could help to avoid perforation. We examined whether visualization of the middle cerebral artery (MCA) by coronal images of nonenhanced computed tomography (coronal CT) provides useful preoperative information on the vessel course in the setting of MT. Methods and Results: We retrospectively studied 29 patients with ischemic stroke of the internal carotid artery and MCA occlusion who were admitted to our hospital within 4.5 hours from stroke onset and underwent MT. Coronal CT images were preoperatively created by a dedicated workstation and adjusted to visualize the M1 segment of the MCA (M1) and nearby areas. We referred to these images while performing MT. The shape and course of M1 on preoperative coronal CT images were compared with that in intraoperative angiography after recanalization. The median time from the start of imaging to arterial puncture was 40 minutes (interquartile range: 32.5-55.0 minutes). Successful recanalization of the thrombolysis in cerebral infarction 2b-3 was achieved in 89.7% of patients. The degree of matching was assessed as moderate to excellent, and was useful as preoperative information in 27 (93.1%) patients. Conclusions: Preoperative information on the vessel course by coronal CT well matched that in the intraoperative angiography. Only a little extra time and a small additional procedure are necessary for this technique. The addition of coronal CT images could contribute to a safe and successful MT.     

Manual Aspiration Thrombectomy Using Penumbra Catheter in Patients with Acute M2 Occlusion : A Single-Center Analysis

ObjectiveThe efficacy and safety of manual aspiration thrombectomy using Penumbra in an acute occlusion of large intracranial arteries has been proven in many previous studies. Our study aimed to retrospectively assess the efficacy and safety of manual aspiration thrombectomy using Penumbra in patients with small vessel occlusions (M2 segment of the MCA).MethodsWe conducted a retrospective review of 32 patients who underwent manual aspiration thrombectomy using the Penumbra 4 MAX Reperfusion Catheter for treatment of an M2 occlusion between January 2013 and November 2014. We evaluated immediate angiographic results and clinical outcomes through review of patient electronic medical records.ResultsThere were slightly more men in this study (M : F=18 : 14) and the median age was 72.5 (age range : 41–90). The rate of successful recanalization (TICI grade ≥2b) was 84% (27/32). NIHSS at discharge and favorable clinical outcomes at 3 months were significantly improved than baseline. Median initial NIHSS score was 10 (range : 4–25) and was 4 (range : 0–14) at discharge. Favorable clinical outcomes (mRS score ≤2 at 3 months) were seen in 25 out of 32 patients (78%). There were no procedure-related symptomatic intracerebral hemorrhages. One patient expired after discharge due to a cardiac problem.ConclusionManual aspiration thrombectomy might be safe and is capable of achieving a high rate of successful recanalization and favorable clinical outcomes in patients with distal cerebral vessel occlusion (M2).     

Transcranial Optical Monitoring of Cerebral Hemodynamics in Acute Stroke Patients during Mechanical Thrombectomy

Introduction: Mechanical thrombectomy is revolutionizing treatment of acute stroke due to large vessel occlusion (LVO). Unfortunately, use of the modified Thrombolysis in Cerebral Infarction score (mTICI) to characterize recanalization of the cerebral vasculature does not address microvascular perfusion of the distal parenchyma, nor provide more than a vascular “snapshot.” Thus, little is known about tissue-level hemodynamic consequences of LVO recanalization. Diffuse correlation spectroscopy (DCS) and diffuse optical spectroscopy (DOS) are promising methods for continuous, noninvasive, contrast-free transcranial monitoring of cerebral microvasculature. Methods: Here, we use a combined DCS/DOS system to monitor frontal lobe hemodynamic changes during endovascular treatment of 2 patients with ischemic stroke due to internal carotid artery (ICA) occlusions. Results and Discussion: The monitoring instrument identified a recanalization-induced increase in ipsilateral cerebral blood flow (CBF) with little or no concurrent change in contralateral CBF and extracerebral blood flow. The results suggest that diffuse optical monitoring is sensitive to intracerebral hemodynamics in patients with ICA occlusion and can measure microvascular responses to mechanical thrombectomy.     

High Stress Hyperglycemia Ratio Predicts Poor Outcome after Mechanical Thrombectomy for Ischemic Stroke

Objective: The present study aimed to evaluate the association between stress hyperglycemia ratio (SHR) and outcome at 3 months after mechanical thrombectomy (MT) for acute occlusion in the anterior circulation. Methods: Data from 160 consecutive patients with large vessel occlusion in the anterior circulation who underwent MT from May 2013 to March 2018 were retrospectively reviewed. SHR was calculated as the fasting glucose concentration divided by the estimated average glucose concentration (derived from the glycosylated hemoglobin level). Patients were dichotomized into 2 groups in accordance with the median SHR. Univariate and multivariate analyses were used to identify predictors of functional outcome. Good and poor outcomes were defined as modified Rankin Scale scores of 0-2 and 3-6, respectively. Results: patients with unfavorable outcome had significantly higher levels of SHR than those with favorable outcome (median in SHR = 1.02 versus .84, P = .000). The median SHR was .96. Univariate analysis showed that significantly more patients with a poor outcome had SHR ≥ .96 compared with those with a good outcome (65.2% versus 31.0%, P = .000). After adjusting for potential covariates, Increased SHR (odds ratio [OR] 6.97, 95% confidence intervals [CI] 1.22-39.65, P = .029, for continuous SHR levels) and SHR ≥ .96 (OR 3.12, 95% CI 1.39-6.96, P = .006) remained independent predictors of poor outcome. Conclusions: Increased SHR is strongly correlated with poor outcome at 3 months after MT for proximal artery occlusion in the anterior circulation.     

Direct Aspiration versus Stent Retriever Thrombectomy for Acute Stroke: A Systematic Review and Meta-Analysis in 9127 Patients

Background: The two most common approaches to thrombectomy of emergent large vessel occlusion (direct aspiration and primary stent retriever thrombectomy) have been extensively studied; however, the detailed benefit and risk comparison is largely unknown. Objective: To conduct a systematic review and meta-analysis to compare radiographic and clinical outcomes between the use of primary stent retrievers and direct aspiration in management of acute ischemic stroke. Methods: PubMed database was searched for studies between September 1, 2012 and December 31, 2017 with acute ischemic stroke patients. Results: We identified 64 studies with 6875 patients in the primary stent retriever group and 25 studies with 2252 patients in the aspiration group. Primary aspiration alone, without the need of rescue stent retriever devices within the aspiration cohort, was performed in 65% of 2252 patients. There was no difference in the distribution of emergent large vessel occlusion based on occlusion site, age, baseline National Institutes of Health Stroke Scale, or the use of intravenous tPA (P?=?.19, .051, .23, and .093, respectively). Successful recanalization rates, defined as thrombolysis in cerebral Infarction 2b/3, were significantly higher in the aspiration group than the primary stent retriever group (89% versus 80%, P < .0001). No significant difference in good clinical outcome, defined as modified Rankin scale 0-2 (aspiration 52% versus stent 48%, P?=?.13), symptomatic intracerebral hemorrhage (aspiration 5.6% versus stent 7.2%, P?=?.07), and mortality at 3 months (aspiration 15% versus stent 19%, P?=?.10). Conclusions: Both aspiration-first (including the subsequent use of stent retriever) and primary stent retriever thrombectomy approaches are equally effective in achieving good clinical outcomes. Our study suggests that direct aspiration with or without subsequent use of stent retriever is a safe and effective alternative to primary stent retriever in acute ischemic stroke.     

大脑中动脉M2段急性闭塞机械取栓临床疗效评估

目的 评估机械取栓应用于大脑中动脉（middle middle cerebral artery,MCA）M2段急性闭塞的有效 性和安全性。 方法 回顾性收集MCA M2段急性闭塞并实施机械取栓患者的临床资料,以90 d mRS评分分为良好 结局（mRS评分0～2分）与不良结局（mRS评分＞2分）组,比较两组基线临床资料、入院NIHSS评分、是 否合并静脉溶栓、闭塞部位、颅内出血（symptomatic intracranial hemorrhage,SICH）、再通时间等资料 的差异。 结果 共入组行机械取栓术的MCA M2段急性闭塞患者12例（男女各6例）。平均年龄（71.4±8.1)岁, 入院NIHSS评分中位数为18分,术后即刻血管再通[改良的脑梗死溶栓（modified thrombolysis in cerebral i nfarcti on,mTI CI ）2b～3级]11例（91.6%）,出血3例（25.0%）,其中SI CH 1例（8.3%）,24 h时血管再通11 例（91.6%）。90 d良好结局组4例,不良结局组8例。良好结局组入院NIHSS评分低于不良结局组（中位 数14分 vs 22分,P =0.038）,两组间其余因素差异无统计学意义。 结论 MCA M2段急性闭塞机械取栓的有效性及安全性有待观察,患者入院时NIHSS评分较低与 90 d预后良好有关。     

Mechanical thrombectomy in patients with proximal occlusions and low NIHSS: Results from a large prospective registry

BackgroundMechanical thrombectomy is now standard of care for treatment of acute ischemic stroke secondary to large vessel occlusion in the setting of high NIHSS. We analysed a large nationwide registry focusing on patients with large vessel occlusion and low NIHSS on admission to evaluate the efficacy and safety of thrombectomy in this patient populationMethods2826 patients treated with mechanical thrombectomy were included in a multicentre registry from January 1, 2011 to December 31, 2015. We included patients with large vessel occlusion and NIHSS ≤ 6 on admission. Baseline characteristics, imaging, clinical outcome, procedure adverse events and positive and negative outcome predictors were analysed.Results134 patients were included. 90/134 had an anterior circulation and 44 a posterior circulation stroke. One patient died before treatment. Successful revascularization (mTICI 2b-3) was achieved in 73.7% (98/133) of the patients. Intraprocedural adverse event was observed in 3% (4/133) of cases. Symptomatic intracranial haemorrhage rate was 5.3% (7/133). At three months, 70.9% (95/134) of the patients had mRS score 0-2, 15.7% (21/134) mRS 3-5 and 13.4% (18/134) mRS 6. Age and successful recanalization were significant predictors of a good clinical outcome on both univariate (p= 0.005 and p=0.007) and multivariable (p=0.0018 and p=0.009 [nat log]) analysis. Absence of vessel recanalization and symptomatic intracranial hemorrhage were independent predictors of poor outcome (p=0.021) .ConclusionsOur study suggests that patients with large vessel occlusion and low NIHSS score on admission can benefit from mechanical thrombectomy. Randomized trials are warranted.