Thrombectomy versus Medical Management for Pediatric Acute Ischemic Stroke Due to Isolated M2 Occlusion: A Multicenter Cohort Study.

M1, M2: Time to Bid Adieu!

Background: The efficacy of endovascular thrombectomy (EVT) in M2 occlusions is uncertain. Methods: In a prospective multicenter cohort study of imaging selection (SELECT), EVT outcomes were compared to medical managment (MM) in M2 occlusions. Further, we assessed for potential treatment benefit in patients with higher stroke severity (NIHSS) and a larger perfusion deficit on CTP (Tmax > 6 sec - ischemic core volume)The primary outcome was excellent outcome (mRS 0-1). Results: of 361 patients enrolled in SELECT, 87 had isolated M2 occlusion (EVT 59, MM 28). Baseline NIHSS median (IQR) (EVT 14 (10-20), MM 15 (9.5-19.5), p=0.72) and infarct volume rCBF<30% (EVT 7 (0-21) vs MM 18.5 (0-41.25), P=0.10). EVT was associated with higher rates of excellent outcomes (53% vs 21%, aOR:6.94, 95% CI=1.86-25.90, p=0.004) with a shift towards better mRS outcomes (adj cOR: 3.49, 95% CI=1.39-8.80, p=0.008), smaller final infarct volume (15.9 (2.7-48.0) vs 58 (24.3-141.9), P<0.001), and a reduction of neurological worsening (3% vs 22%, p=0.011), sICH (2% vs 21%, p=0.004), and mortality (5% vs 25%, p=0.011). Assessing outcomes in NIHSS strata; there was no significant increase in excellent outcomes rates in NIHSS ≤10 (EVT 65% vs MM 50%, aOR=1.59, 95% CI=0.21-12.01, p=0.65). In contrast, patients with NIHSS>10 had better outcomes with EVT (46%) vs MM (10%), aOR=11.39, 95% CI=1.80-72.11, p=0.01 as shown in figure 1. As perfusion deficit lesion size increased, the odds of achieving excellent outcomes was reduced (for each 10cc by 11%, aOR: 0.89, 95% CI=0.79-1.00, p=0.05). Excellent outcomes declined in patients with MM as perfusion deficit lesion size increased, yet in the EVT they were maintained as shown in figure 2. Similar results were obtained for mRS 0-2. Conclusion: EVT may result in better rates of excellent outcomes in isolated M2 occlusions, especially those with more severe strokes and larger perfusion deficits who are more likely to have worse outcomes without emergent reperfusion.

Background: The efficacy of endovascular thrombectomy (EVT) in M2 occlusions is uncertain. Methods: In a pooled patient level analysis of the prospective multicenter cohort study of imaging selection (SELECT) and the INternational Stroke Perfusion Imaging REgistry (INSPIRE) EVT outcomes were compared to medical management (MM) in M2 occlusions. Further, we assessed for potential treatment benefit in patients with higher stroke severity (NIHSS). The primary outcome was excellent outcome (mRS 0-1). Results: 387 patients with isolated M2 occlusion (EVT 112, MM 275) met the inclusion criteria. Baseline NIHSS median (IQR) (EVT: 13 (9-19), MM: 10 (6-15), p<0.001) and infarct volume rCBF<30% (EVT 11 (4-24) vs MM: 8 (3-16), P=0.11). EVT was associated with a trend towards higher rates of excellent outcomes (48% vs 44%, aOR:2.80, 95% CI=0.95-8.25, p=0.061) with a shift towards better mRS outcomes (adj cOR: 2.57, 95% CI=1.11-5.94, p=0.028), and a reduction of neurological worsening (27% vs 47%, p<0.001) and numerically lower rates of sICH (4.5% vs 6.5%, p=0.43), and mortality (4.5% vs 9.5%, p=0.10). Assessing outcomes in NIHSS strata; there was no significant difference in excellent outcomes rates in patients with NIHSS ≤10 (EVT 62% vs MM 57%, aOR=2.18, 95% CI=0.30-15.73, p=0.44). In contrast, patients with NIHSS>10 had a trend towards higher excellent outcome rates outcomes with EVT (43%) vs MM (27%), aOR=3.11, 95% CI=0.81-11.95, p=0.098) as shown in figure 1. Conclusion: EVT may result in better rates of excellent outcomes in isolated M2 occlusions, especially those with more severe strokes who are more likely to have worse outcomes without emergent reperfusion.

Mechanical thrombectomy is an effective recanalization technique in acute ischemic stroke patients with large vessel occlusions; however, it is unclear to what extent stent retriever thrombectomy may be applicable to occlusions of smaller peripheral cerebral vessels. The outcome of patients with isolated M2 occlusions treated with the Mindframe Capture low profile (LP) stent retriever was reviewed. Aretrospective review of prospectively collected data on all consecutive patients treated for isolated M2 occlusions between June 2013 and December 2017 using the Mindframe Capture LP was performed. Technical aspects of the recanalization procedure, recanalization rate, complication rate, and clinical outcome were analyzed. Mechanical thrombectomy with the Mindframe Capture LP was performed in 38patients (median age 79years) with an isolated M2 occlusion. The median National Institutes of Health Stroke Scale (NIHSS) score on admission was 7.5 (interquartile range, IQR 5-12) and successful reperfusion modified Thrombolysis in Cerebral Infarction (mTICI2b or 3) was achieved in 28patients (74%). Acompensated/adjusted modified Rankin Scale (mRS) 0-2 at 3months was observed in 65% when taking pre-stroke disability into account. Symptomatic intracranial hemorrhage (sICH) occurred in 1patient (2.6%). Asymptomatic intracranial hemorrhage (aICH) was noted in 8patients (21%) and asmall subarachnoid hemorrhage (SAH) in the immediate vicinity of the target vessel was apparent in 8patients (21%). The Mindframe Capture LP is atechnically effective thrombectomy device for the treatment of isolated M2 occlusions. The lower profile of the device is advantageous when targeting peripheral intracranial occlusions.

Objective Currently, the standard treatment modality for patients with acute ischemic stroke (AIS) presenting with isolated M2 occlusions is not specific. We therefore assessed the difference in treatment outcomes for patients with isolated M2 occlusions. Methods We retrospectively analyzed consecutive patients with AIS presenting with isolated M2 occlusions from October 1, 2018, to June 30, 2020. Patients were divided into 3 groups based on the treatments they received: no reperfusion therapy (NRT), intravenous thrombolysis treatment (IVT), and endovascular intervention (EVT), which comprised IVT in conjunction with EVT or EVT alone. The primary outcomes were improvements in modified Rankin Scale (mRS) scores at 90 days and National Institutes of Health Stroke Scale (NIHSS) scores at 24 hours after treatment compared with the baseline. The secondary efficacy outcome comprised a good outcome rate defined as a 90 − day mRS score ≤ 2, final infarct volume (FIV), 90-day mortality rate, and successful recanalization rate, which was defined as a modified thrombolysis in cerebral infarction score ≥ 2b. Safety outcomes included symptomatic intracerebral hemorrhage and procedure-related complications. Results Seventy patients were enrolled and divided into 3 groups: the NRT group (n = 25), IVT group (n = 27), and EVT group (n = 18). Twenty-four-hour posttreatment NIHSS scores were substantially decreased by EVT compared with NRT (adjusted β -4.01, 95% confidence interval [CI] -6.60 to -1.43; P = 0.003) or IVT (adjusted β, -3.61 [95% CI, -6.45 to -0.77]; P = 0.013). Compared with the outcomes observed after NRT, patients who received EVT were more likely to achieve lower 90-day mRS scores (adjusted β, -1.42 [95% CI, -2.66 to -0.63]; P = 0.007), higher good outcome rates (adjusted odds ratio, 8.73 [95% CI, 1.43-53.24]; P = 0.019), and smaller FIVs (adjusted β, -29.66 [95% CI, -59.73 to 0.42]; P = 0.048). The recanalization rate of EVT was high (88.89%), and procedure-related complications were rare (5.56%). Conclusions For acute, isolated M2 occlusions, EVT could dramatically and rapidly improve neurological deficits with high safety and effectiveness. These changes were observed at 24 hours after treatment and were maintained over the long term.

BackgroundThe purpose of this study was to evaluate the effectiveness of mechanical thrombectomy (MT) in patients with isolated M2 occlusion and minor symptoms and identify possible baseline predictors of clinical...

Endovascular thrombectomy or bridging therapy in minor ischemic stroke with large vessel occlusion

Background: Most trials for the endovascular thrombectomy (EVT) of large vessel ischemic stroke excluded patients with large core infarcts and low Alberta Stroke Program Early CT Score (ASPECTS). As a result, the current American Heart Association guidelines for acute ischemic stroke reserve Grade 1A recommendation for the use of EVT for patients with an ASPECTS of 6 or more. However recent data from the HERMES collaboration has shown that even stroke patients with large core infarcts may still benefit from EVT. Objectives: Through this systematic review, we aim to determine the safety and efficacy of EVT for large vessel ischemic stroke patients with low ASPECTS (5 or less). Methods: Medline, Cochrane Central Register of Systematic Reviews and ClinicalTrials.gov were searched for studies appraising the outcomes of EVT for low ASPECTS acute ischemic stroke patients. Patients with low ASPECTS who underwent EVT were compared to those who only received best medical therapy (BMT). A meta-analysis of proportions was done to compare the outcomes of the two groups in terms of symptomatic intracranial hemorrhage, mortality and good 3-month functional outcomes (modified Rankin Scale < 2). Results: Nine studies with a total of 1,196 acutes stroke patients with low ASPECTS (712 undergoing EVT and 484 with only BMT) were included in the study. There was a trend towards a higher rate of sICH in the EVT group (9.2%; 95% CI 6.1% to 13.6%; I 2 53.37%) compared to the BMT group (5.5%; 95% CI 3.7% to 8.1%; I 2 =0%) but this did not reach statistical significance (p=0.11). There was no difference (p=0.41) in the pooled 3-month mortality of EVT patients (30.7%; 95% CI 21.7 to 41.5%; I 2 84.23%) and BMT patients (36.6%; 95% CI 26.4% to 48.1%; I 2 76.2%). Patients who underwent EVT had significantly better (p=0.001) 3-month outcomes, with 27.7% (95% 21.8 to 34.5%; I 2 62.08%) of patients attaining an MRS 0-2 compared to only 3.7% (95% 2.3 to 5.9%; I 2 87.21%) of patients in the BMT. Conclusion: Our meta-analysis suggests that acute stroke patients with low ASPECTS score may still benefit from EVT. Larger registry based studies and randomized controlled trials are needed to further substantiate the findings of our review.

Multiple recent randomized trials have demonstrated the benefit of thrombectomy over medical management alone in adult patients with large vessel occlusion (LVO) stroke and large infarct on baseline imaging. Cohort studies have also identified improved functional outcomes in pediatric patients who received thrombectomy. However, the role of thrombectomy in pediatric stroke with large baseline infarct remains uncertain. A case-control study was undertaken using pooled data from 3 cohort studies of pediatric stroke (Save ChildS [Safety and Outcome of Endovascular Recenalization in Childhood Stroke Study], Save ChildS Pro [Safety and Outcome of Endovascular Recenalization in Childhood Stroke Prospective Registry], Pediatric LVO Stroke Study). Pediatric patients of age 1 to 18 years with acute anterior circulation LVO stroke presenting within 24 hours since last seen well with an Alberta Stroke Program Early CT Score of 0 to 5 on CT or magnetic resonance imaging were included. Isolated M2 occlusion or focal cerebral arteriopathy-inflammatory subtype cases were excluded. Thrombectomy-treated patients were compared with patients who received medical management alone. The primary clinical outcome was the pediatric modified Rankin Scale score at 90 days, compared between groups using ordinal logistic regression. Of 56 pediatric patients with anterior circulation LVO and low Alberta Stroke Program Early CT Score presenting between January 1, 2000 and August 31, 2023 from 45 centers across Europe, North America, and Australia, 40 patients were eligible for inclusion (female: n=14, 35.0%; mean age, 9.1 years; range, 1.5-17; SD, 5.27). Thrombectomy-treated patients (n=24) had significantly better pediatric modified Rankin Scale scores at 90 days than medical management alone patients (n=16; odds ratio, 3.68 [95% CI, 1.11-12.21]; P=0.034). There was no significant difference between groups in the rate of symptomatic intracranial hemorrhage (P=0.806). In this multicentre case-control study, pediatric patients (age, 1-18 years) with anterior circulation LVO stroke and low Alberta Stroke Program Early CT Score who received thrombectomy had significantly better functional outcomes than those treated with medical management alone. Exclusion of pediatric patients from thrombectomy based on low Alberta Stroke Program Early CT Score alone may not be appropriate.

BackgroundTo evaluate the cost-effectiveness of endovascular thrombectomy (EVT) to treat large vessel occlusion (LVO) in patients with acute, minor stroke (National Institute of Health Stroke Scale (NIHSS) <6) and impact...

Emerging evidence suggests that endovascular thrombectomy is beneficial for treatment of childhood stroke, but the safety and effectiveness of endovascular thrombectomy has not been compared with best medical treatment. We aimed to prospectively analyse functional outcomes of endovascular thrombectomy versus best medical treatment in children with intracranial arterial occlusion stroke. In this prospective registry study, 45 centres in 12 countries across Asia and Australia, Europe, North America, and South America reported functional outcomes for children aged between 28 days and 18 years presenting with arterial ischaemic stroke caused by a large-vessel or medium-vessel occlusion who received either endovascular thrombectomy plus best medical practice or best medical treatment alone. Intravenous thrombolysis was considered part of best medical treatment and therefore permitted in both groups. The primary outcome was the difference in median modified Rankin Scale (mRS) score between baseline (pre-stroke) and 90 days (±10 days) post-stroke, assessed by the Wilcoxon rank test (α=0·05). Efficacy outcomes in the endovascular thrombectomy and best medical treatment groups were compared in sensitivity analyses using propensity score matching. The Save ChildS Pro study is registered at the German Clinical Trials Registry, DRKS00018960. Between Jan 1, 2020, and Aug 31, 2023, of the 241 patients in the Save ChildS Pro registry, 208 were included in the analysis (115 [55%] boys and 93 [45%] girls). 117 patients underwent endovascular thrombectomy (median age 11 years [IQR 6-14]), and 91 patients received best medical treatment (6 years [3-12]; p<0·0001). The median Pediatric National Institutes of Health Stroke Scale (PedNIHSS) score on admission was 14 (IQR 10-19) in the endovascular thrombectomy group and 9 (5-13) in the best medical treatment group (p<0·0001). Both treatment groups had a median pre-stroke mRS score of 0 (IQR 0-0) at baseline. The change in median mRS score between baseline and 90 days was 1 (IQR 0-2) in the endovascular thrombectomy group and 2 (1-3) in the best medical treatment group (p=0·020). One (1%) patient developed a symptomatic intracranial haemorrhage (this patient was in the endovascular thrombectomy group). Six (5%) patients in the endovascular thrombectomy group and four (5%) patients in the best medical treatment group had died by day 90 (p=0·89). After propensity score matching for age, sex, and PedNIHSS score at hospital admission (n=79 from each group), the change in median mRS score between baseline and 90 days was 1 (IQR 0-2) in the endovascular thrombectomy group and 2 (1-3) in the best medical treatment group (p=0·029). Regarding the primary outcome for patients with suspected focal cerebral arteriopathy, endovascular thrombectomy (n=18) and best medical treatment (n=33) showed no difference in 90-day median mRS scores (2 [IQR 1-3] vs 2 [1-4]; p=0·074). Clinical centres tended to select children with more severe strokes (higher PedNIHSS score) for endovascular thrombectomy. Nevertheless, endovascular thrombectomy was associated with improved functional outcomes in paediatric patients with large-vessel or medium-vessel occlusions compared with best medical treatment. Future studies need to investigate whether the positive effect of endovascular thrombectomy is confined to older and more severely affected children. None.

Background and Purpose- Endovascular thrombectomy (EVT) is effective for acute ischemic stroke with large vessel occlusion and National Institutes of Health Stroke Scale (NIHSS) ≥6. However, EVT benefit for mild deficits large vessel occlusions (NIHSS, <6) is uncertain. We evaluated EVT efficacy and safety in mild strokes with large vessel occlusion. Methods- A retrospective cohort of patients with anterior circulation large vessel occlusion and NIHSS <6 presenting within 24 hours from last seen normal were pooled. Patients were divided into 2 groups: EVT or medical management. Ninety-day mRS of 0 to 1 was the primary outcome, mRS of 0 to 2 was the secondary. Symptomatic intracerebral hemorrhage was the safety outcome. Clinical outcomes were compared through a multivariable logistic regression after adjusting for age, presentation NIHSS, time last seen normal to presentation, center, IV alteplase, Alberta Stroke Program early computed tomographic score, and thrombus location. We then performed propensity score matching as a sensitivity analysis. Results were also stratified by thrombus location. Results- Two hundred fourteen patients (EVT, 124; medical management, 90) were included from 8 US and Spain centers between January 2012 and March 2017. The groups were similar in age, Alberta Stroke Program early computed tomographic score, IV alteplase rate and time last seen normal to presentation. There was no difference in mRS of 0 to 1 between EVT and medical management (55.7% versus 54.4%, respectively; adjusted odds ratio, 1.3; 95% CI, 0.64-2.64; P=0.47). Similar results were seen for mRS of 0 to 2 (63.3% EVT versus 67.8% medical management; adjusted odds ratio, 0.9; 95% CI, 0.43-1.88; P=0.77). In a propensity matching analysis, there was no treatment effect in 62 matched pairs (53.5% EVT, 48.4% medical management; odds ratio, 1.17; 95% CI, 0.54-2.52; P=0.69). There was no statistically significant difference when stratified by any thrombus location; M1 approached significance ( P=0.07). Symptomatic intracerebral hemorrhage rates were higher with thrombectomy (5.8% EVT versus 0% medical management; P=0.02). Conclusions- Our retrospective multicenter cohort study showed no improvement in excellent and independent functional outcomes in mild strokes (NIHSS, <6) receiving thrombectomy irrespective of thrombus location, with increased symptomatic intracerebral hemorrhage rates, consistent with the guidelines recommending the treatment for NIHSS ≥6. There was a signal toward benefit with EVT only in M1 occlusions; however, this needs to be further evaluated in future randomized control trials.

Background: Limited information is available regarding the outcomes after distal middle cerebral artery stroke. To gain a better understanding, the aim of our study was to assess for factors associated with outcome following M2 middle cerebral artery occlusion infarcts. Methods: We retrospectively reviewed admission computed tomography (CT)-angiography (CTA) of consecutive acute ischemic stroke patients admitted to a single academic center from January 2010 to August 2012. Only patients with isolated M2 occlusion (defined as an occlusion distal to the bifurcation and proximal to further division) were included. We assessed for factors associated with a good 90-day outcome (modified Rankin Scale [mRS] score ≤2). Factors associated with an mRS ≤2 in univariable analyses (p&lt;0.05) were entered into multivariable logistic regression analysis. Admission National Institutes of Health Stroke Scale (aNIHSS), age, and infarct volume were also entered as dichotomized variables. Receiver operating characteristic (ROC) curves were plotted to determine the optimal aNIHSS score, infarct volume, and age cut points predicting an mRS ≤2. Optimal thresholds were determined by maximizing Youden’s index. Results: 90 patients with isolated M2 occlusions were included in final analyses. Of these, 69% had a 90-day mRS ≤2. Age ≤80 years (OR 0.37, 95%-CI 0.003-0.416, p=0.008), aNIHSS ≤10 (OR 0.05, 95%-CI 0.009-0.36, p=0.002), and infarct volume &lt;27 ml (OR 0.009, 95%-CI 0.001-0.15, p=0.001) were independent predictors of a good 90-day outcome. Entering age, aNIHSS, and infarct volume as continuous variables did not meaningfully change these results. Notably, 20% patients (64% of those with a poor outcome) had died by 90-days. We then repeated all analyses for predictors of 90-day mortality. This analysis indicated that age ≤80 years (OR 4.7, 95%-CI 1.25-18, p=0.02) and infarct volume &lt;26 ml (OR 7.3, 95%-CI 1.4-38.5, p&lt;0.001) were independently associated with 90-day mortality. Conclusion: The majority of patients with isolated M2 occlusion strokes have a good 90-day outcome, which is predicted by younger age, lower aNIHSS, and smaller infarct size. Further investigations are required to identify specific factors predicting death in this patient population.

Background: Factors influencing outcome after cerebral artery occlusion are not completely understood. Although it is well accepted that the site of arterial occlusion critically influences outcome, the majority of studies investigating this issue has focused on proximal large artery occlusion. To gain a better understanding of factors influencing outcome after distal large artery occlusion, we sought to assess predictors of outcome following isolated M2 middle cerebral artery occlusion infarcts. Methods: We retrospectively analyzed patients with isolated acute M2 occlusion admitted to a single academic center from January 2010 to August 2012. Baseline clinical, laboratory imaging, and outcome data were assessed from a prospectively collected database. Factors associated with a modified Rankin Scale (mRS) score ≤2 in univariable analyses (p < 0.05) were entered into multivariable logistic regression analysis. The Admission National Institutes of Health Stroke Scale (aNIHSS) score, age, and infarct volume were also entered as dichotomized variables. Receiver operating characteristic curves were plotted to determine the optimal aNIHSS score, infarct volume, and age cut points predicting an mRS score ≤2. Optimal thresholds were determined by maximizing the Youden index. Respective multivariable logistic regression analyses were used to identify independent predictors of a good 90-day outcome (mRS score ≤2; primary analysis) as well as 90-day mortality (secondary outcome). Results: 90 patients with isolated M2 occlusion were included in the final analyses. Of these, 69% had a good 90-day outcome which was associated with age <80 years (p = 0.007), aNIHSS <10 (p = 0.002), and infarct volume ≤26 ml (p < 0.001). Notably, 20% of patients (64% of those with a poor outcome) had died by 90 days. Secondary analysis for 90-day mortality was performed. This analysis indicated that infarct volume >28 ml (OR 11.874, 95% CI 2.630-53.604, p = 0.001), age >80 years (OR 4.953, 95% CI 1.087-22.563, p = 0.039), need for intubation (OR 7.788, 95% CI 1.072-56.604), and history of congestive heart failure (OR 5.819, 95% CI 1.140-29.695) were independent predictors of 90-day mortality (20% of all included patients). Conclusion: While the majority of patients with isolated M2 occlusion stroke has a good 90-day outcome, a substantial proportion of subjects dies by 90 days, as identified by a unique subset of predictors. The knowledge gained from our study may lead to an improvement in the prognostic accuracy, clinical management, and resource utilization in this patient population.

Middle cerebral artery M2-segment occlusions represent an important subgroup of patients with acute stroke with large-vessel occlusion. The safety of mechanical thrombectomy, especially contact aspiration (CA), in such distal intracranial occlusions is still under debate. We compared reperfusion, adverse events, neurological recovery, and functional outcome of patients with isolated M2 occlusions according to the first-line strategy mechanical thrombectomy devices (CA versus stent retriever [SR]). This is a post hoc analysis of the ASTER trial (Contact Aspiration Versus Stent Retriever for Successful Revascularization). The primary outcome was successful reperfusion at the end of all endovascular procedures, defined as modified Thrombolysis in Cerebral Infarction (mTICI) scores 2b/3. Secondary outcomes were mTICI 2c/3 and mTICI 3, 90-day functional outcome, assessed with the modified Rankin Scale score. Safety outcomes included 90-day mortality and any symptomatic intracerebral hemorrhage. Seventy-nine patients were included: 48 were allocated to the CA group and 31 to the SR group. There were no significant differences between CA and SR groups in reperfusion after all endovascular procedures regarding mTICI 2b/3 (89.6% versus 83.9%; P=0.36), mTICI 2c/3 (54.2% versus 54.8%; P=0.90), and mTICI 3 (35.4% versus 41.9%; P=0.36) rates. There were no significant differences between CA and SR groups in 90-day modified Rankin Scale ≤2 rate (54.4% versus 50.0%; P=0.84), 24-hour change in National Institutes of Health Stroke Scale (mean difference, -3.9; 95% confidence interval, -7.9 to 0.01), and Alberta Stroke Program Early Computed Tomography score (mean difference, 0.9; 95% confidence interval, -0.1 to 2.0) scores. Safety parameters were well balanced between the 2 groups except for a higher 90-day mortality rate in the CA group (19.6% versus 3.3%; P=0.078). First-line mechanical thrombectomy with CA compared with SR did not result in an increased successful revascularization rate in patients with acute stroke with isolated M2 occlusion.