"Pediatric Spontaneous Intracranial Dissecting Aneurysms: Impact of Ischemic and Hemorrhagic Manifestations on Endovascular Treatment Strategies - Insights from a Developing World Setting".

BACKGROUND: Pediatric spontaneous intracranial dissecting aneurysms are rare, but systematic studies comparing hemorrhagic and ischemic presentations are lacking. This study addresses gaps in understanding their epidemiology, clinical presentation, management, and outcome. METHODS: A retrospective analysis of 23 pediatric patients with nontraumatic intracranial dissecting aneurysms treated between July 2018 and December 2023 was conducted. Patients were divided into 2 groups based on presentation: hemorrhagic (n = 16) and ischemic (n = 7). Clinical data were analyzed, including demographics, radiologic findings, treatment modalities, and outcomes. RESULTS: Clinical presentations varied, with limb weakness being more prevalent in hemorrhagic cases (P = 0.014), while headache and seizures were more common in ischemic cases. Angiographic analysis revealed distinct patterns, with hemorrhagic cases showing more distal involvement on vessel segments with stenosis and dilatation (pearl string sign). At the same time, the ischemic group exhibited the double-lumen sign. Various treatments, including microsurgery and endovascular techniques, were utilized, with perioperative complications observed, including one mortality in a hemorrhagic case. Multiple regression analysis identified significant risk factors for perioperative complications, namely, the configuration of the dissecting aneurysm (P = 0.016) and the type of presentation (P = 0.0006). Long-term Glasgow Outcome Scores were comparable, but patients with hemorrhagic manifestations experienced prolonged hospital and ICU stays (P = 0.001). CONCLUSIONS: Pediatric intracranial dissecting aneurysms, particularly hemorrhagic cases, are associated with severe neurologic deficits and higher perioperative complications. Despite similar long-term outcomes, hemorrhagic cases require prolonged hospitalization, increasing treatment costs. Optimizing management strategies for pediatric intracranial dissecting aneurysms, especially those with hemorrhagic features, is essential to improve outcomes and reduce healthcare expenditures.

Endovascular therapy in patients with a large ischemic volume at presentation: An aggregate patient-level analysis.

INTRODUCTION: Recently, four randomized controlled trials (RCTs) have demonstrated the benefits of mechanical thrombectomy (MT) in patients with acute ischemic stroke (AIS) caused by anterior large vessel occlusion (LVO) and a large ischemic core at baseline (LIC). The purpose of this study was to investigate the features influencing the clinical outcome and the benefits of mechanical thrombectomy in this subgroup. METHODS: We conducted a multicenter retrospective aggregate cohort study of patients with AIS-LVO and a LIC, assessed with quantitative core volume measures, treated with MT between 2012 and 2019. The data were queried through four registries, including patients with core volumes ≥50cc. Multivariable logistic regression models were employed to determine factors independently associated with clinical outcomes in patients with successful recanalization (modified-Thrombolysis-in-Cerebral-Infarction-score, mTICI=2b-3) and unsuccessful recanalization group (mTICI=0-2a). The primary endpoint was a favorable functional outcome at day-90, defined as a modified Rankin scale (mRS) of 0-3, accounting for the inherent severity of AIS with baseline LIC. Secondary outcomes included functional independence (mRS 0-2) at day-90, mortality, and symptomatic Intracranial Hemorrhage (sICH). RESULTS: A total of 460 patients were included (mean age 66±14.2 years; 39.6 % females). The mean baseline NIHSS was 20±5.2, and the core volume was 103.2±54.6 ml. Overall, 39.8 % (183/460) of patients achieved a favorable outcome at day-90 (mRS 0-3). Successful recanalization was significantly associated with a more frequent favorable outcome (aOR, 4.79; 95 %CI, 2.73-8.38; P<0.01) and functional independence (P<0.01). This benefit remained significant in older patients and in patients with cores above 100cc. At 90 days, 147/460 patients (32 %) were deceased, with successful recanalization significantly associated with less frequent mortality (OR, 0.34; 95 %CI, 0.22-0.53; P<0.01). The rate of sICH was 17.4 % and did not differ significantly between groups. CONCLUSIONS: In this large, pooled-cohort study of AIS-LVO patients with infarct cores over 50cc at baseline, we demonstrated that successful recanalization was associated with a better functional outcome, lower mortality, and similar rates of symptomatic intracranial hemorrhage for a wide spectrum of patients.

Microsurgical clipping versus endovascular therapy for treating patients with middle cerebral artery aneurysms presenting with neurological ischemic symptoms.

Studies comparing different treatment methods in patients with middle cerebral artery (MCA) aneurysms in different subgroups of onset symptoms are lacking. It is necessary to explore the safety and efficacy of open surgical treatment and endovascular therapy in patients with MCA aneurysms in a specific population. This study aimed to compare microsurgical clipping versus endovascular therapy regarding complication rates and outcomes in patients with MCA aneurysms presenting with neurological ischemic symptoms. This was a retrospective cohort study in which 9656 patients with intracranial aneurysms were screened between January 2014 and July 2022. Further, 130 eligible patients were enrolled. The primary outcome was the incidence of serious adverse events (SAEs) within 30 days of treatment, whereas secondary outcomes included postprocedural target vessel-related stroke, disabling stroke or death, mortality, and aneurysm occlusion rate. Among the 130 included patients, 45 were treated with endovascular therapy and 85 with microsurgical clipping. The primary outcome of the incidence of SAEs within 30 days of treatment was significantly higher in the clipping group [clipping: 23.5%(20/85) vs endovascular: 8.9%(4/45), adjusted OR:4.05, 95% CI:1.20-13.70; P = 0.024]. The incidence of any neurological complications related to the treatment was significantly higher in the clipping group [clipping:32.9%(28/85) vs endovascular:15.6%(7/45); adjusted OR:3.49, 95%CI:1.18-10.26; P = 0.023]. Postprocedural target vessel-related stroke, disabling stroke or death, mortality rate, and complete occlusion rate did not differ significantly between the two groups. Endovascular therapy seemed to be safer in treating patients with MCA aneurysms presenting with neurological ischemic symptoms compared with microsurgical clipping, with a significantly lower incidence of SAEs within 30 days of treatment and any neurological complications related to the treatment during follow-up.

Cerebral Ischemic Coma Model Induced by Modified Four-Vessel Occlusion.

Coma caused by cerebral ischemia is the most serious complication of cerebral ischemia. Four-vessel occlusion can establish a cerebral ischemic coma model for disease research and drug development. However, the commonly used four-vessel occlusion method mainly involves inserting an electrocoagulation pen into the bilateral pterygoid foramen of the first cervical vertebra behind the neck to electrocoagulate the vertebral arteries. This process carries the risk of incomplete electrocoagulation, bleeding, and damage to the brainstem and spinal cord. Twenty-four hours after surgery, re-anesthetized rats undergo carotid artery ligation in front of the neck. Two surgeries expose the rats to a higher risk of infection and increase the experimental period. In this study, during a single surgical procedure, an anterior cervical incision was used to locate the key site where the vertebral artery penetrates the first cervical vertebra. The bilateral vertebral arteries were electrocauterized under visual conditions, while the bilateral common carotid arteries were separated to place loose knots. When the rats showed consciousness of the inversion reaction, the bilateral common carotid arteries were quickly ligated to induce ischemic coma. This method can avoid the risk of infection caused by two surgical operations and is easy to perform with a high success rate, providing a useful reference for relevant practitioners.

Combining Early Ischemic Change and Collateral Extent for Functional Outcomes After Endovascular Therapy: An Analysis From AcT Trial.

BACKGROUND: Early ischemic change and collateral extent are colinear with ischemic core volume (ICV). We investigated the relationship between a combined score using the Alberta Stroke Program Early Computed Tomography Score and multiphase computed tomography angiography (mCTA) collateral extent, named mCTA-ACE score, on functional outcomes in endovascular therapy-treated patients. METHODS: We performed a post hoc analysis of a subset of endovascular therapy-treated patients from the Alteplase Compared to Tenecteplase trial which was conducted between December 2019 and January 2022 at 22 centers across Canada. Ten-point mCTA collateral corresponding to M2 to M6 regions of the Alberta Stroke Program Early Computed Tomography Score grid was evaluated as 0 (poor), 1 (moderate), or 2 (normal) and additively combined with the 10-point Alberta Stroke Program Early Computed Tomography Score to produce a 20-point mCTA-ACE score. We investigated the association of mCTA-ACE score with modified Rankin Scale score ≤2 and return to prestroke level of function at 90 to 120 days using mixed-effects logistic regression. In the subset of patients who underwent baseline computed tomography perfusion imaging, we compared the mCTA-ACE score and ICV for outcome prediction. RESULTS: Among 1577 intention-to-treat population in the trial, 368 (23%; 179 men; median age, 73 years) were included, with Alberta Stroke Program Early Computed Tomography Score, mCTA collateral, and combination of both (mCTA-ACE score: median [interquartile range], 8 [7-10], 9 [8-10], and 17 [16-19], respectively). The probability of modified Rankin Scale score ≤2 and return to prestroke level of function increased for each 1-point increase in mCTA-ACE score (odds ratio, 1.16 [95% CI, 1.06-1.28] and 1.22 [95% CI, 1.06-1.40], respectively). Among 173 patients in whom computed tomography perfusion data was assessable, the mCTA-ACE score was inversely correlated with ICV (ρ=-0.46; P<0.01). The mCTA-ACE score was comparable to ICV to predict a modified Rankin Scale score ≤2 and return to prestroke level of function (C statistics 0.71 versus 0.69 and 0.68 versus 0.64, respectively). CONCLUSIONS: The mCTA-ACE score had a significant positive association with functional outcomes after endovascular therapy and had a similar predictive performance as ICV.

Expanding the Treatable Imaging Profile in Patients With Large Ischemic Stroke: Subanalysis From a Randomized Clinical Trial.

BACKGROUND: We aimed to examine the boundary of the ischemic core volume in patients undergoing endovascular thrombectomy (EVT) versus those receiving medical management to determine the minimum optimal size for favorable treatment outcomes. METHODS: This is a prespecified substudy of the RESCUE-Japan LIMIT (Recovery by Endovascular Salvage for Cerebral Ultra-Acute Embolism-Japan Large Ischemic Core Trial). Patients with large vessel occlusion were enrolled between November 2018 and September 2021 with a National Institutes of Health Stroke Scale score of at least 6 on admission and an Alberta Stroke Program Early Computed Tomography Score value of 3 to 5. We investigated the correlation between optimal quantified ischemic core volume, assessed solely using magnetic resonance diffusion-weighted imaging, and functional outcomes (modified Rankin Scale score, 0-3) at 90 days by predictive marginal plots. Final infarct volume and safety outcomes (symptomatic intracerebral hemorrhage and mortality) were also assessed. RESULTS: Of the 203 cases, 168 patients (85 in the EVT group versus 83 in the medical management group) were included. The median (interquartile range) core volume was 94 (65-160) mL in patients with EVT and 115 (71-141) mL in the medical management group (P=0.72). The predictive marginal probabilities of the 2 groups intersected at 128 mL for estimating functional outcomes. Symptomatic intracerebral hemorrhage and mortality within 90 days had overlay margins through all core volumes in both groups. The median final infarct volume (interquartile range) was smaller in the EVT group (142 [80-223] mL versus 211 [123-289] mL in the medical management group; P<0.001). CONCLUSIONS: In this prespecified analysis of a randomized clinical trial involving patients with large ischemic strokes, patients with an estimated core volume of up to 128 mL on diffusion-weighted imaging benefit from EVT. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03702413.

Stent-retriever characteristics and strategies associated with recanalization in thrombectomy for acute ischemic stroke.

INTRODUCTION: Predictive factors for successful reperfusion in mechanical thrombectomy for acute ischemic stroke, and especially technical factors, remain controversial. We investigated various techniques for better angiographic outcomes. METHODS: In this retrospective study, acute ischemic stroke patients with large vessel occlusion treated with mechanical thrombectomy with combined technique were included. Scoring of the reperfusion grade for each attempt was conducted, and each attempt was divided into two groups based on successful reperfusion, which was defined using the presence or absence of modified thrombolysis in cerebral infarction 2b-3. The following characteristics were evaluated: the choice of stent-retriever, its length, occlusion site, thrombus position relative to deployed stent-retriever, methods of thrombectomy, and successful advancement of the distal access catheter to the proximal end of the thrombus. RESULTS: Among 251 patients who underwent mechanical thrombectomy, 154 patients (255 attempts: mTICI 0-2a group, n = 119; mTICI 2b-3 group, n = 136) were included in the analysis. The thrombus position relative to the deployed stent-retriever was likely associated with successful reperfusion, although it was not statistically significant (proximal two-thirds 56.8 %; distal one-third 44.3 %, p = 0.09). Successful advancement of the distal access catheter was related to successful reperfusion both in univariate analysis (success 57.9 %; fail 35.8 %, p < 0.01) and in multivariate regression analysis (odds ratio 2.45; 95 % confidence interval: 1.30-4.61, p < 0.01). CONCLUSIONS: Successful advancement of the distal access catheter to the proximal end of thrombus might be a key component for successful reperfusion in mechanical thrombectomy.

Intraoperative intensive blood pressure management strategy and the outcome of patients who had an acute ischaemic stroke undergoing endovascular treatment under general anaesthesia: study protocol for a prospective randomised controlled trial.

BackgroundEndovascular thrombectomy is the recommended treatment for acute ischaemic stroke, but the optimal blood pressure management strategy during the procedure under general anaesthesia remains controversial. In this study protocol, we propose an intraoperative intensive blood pressure range (110-140 mm Hg systolic blood pressure) based on a retrospective analysis and extensive literature review. By comparing the outcomes of patients who had an acute ischaemic stroke undergoing mechanical thrombectomy under general anaesthesia with standard blood pressure management (140-180 mm Hg systolic blood pressure) versus intensive blood pressure management, we aim to determine the impact of intraoperative intensive blood pressure management strategy on patient prognosis. METHODS AND ANALYSIS: The study is a double-blinded, randomised, controlled study, with patients randomised into either the standard blood pressure management group or the intensive blood pressure management group. The primary endpoint of the study will be the sequential analysis of modified Rankin Scale scores at 90 days after mechanical thrombectomy. ETHICS AND DISSEMINATION: The study has been approved by the ethics committee of Shanghai Changhai Hospital with an approval number CHEC2023-015. The results of the study will be published in peer-reviewed international journals. TRIAL REGISTRATION NUMBER: ChiCTR2300070764.

Long term outcome after endovascular treatment for large ischemic core acute stroke is associated with hypoperfusion intensity ratio and onset-to-reperfusion time.

BACKGROUND: Endovascular treatment (EVT) is effective for large vessel occlusion (LVO) stroke with smaller volumes of CT perfusion (CTP)-defined core. However, the influence of perfusion imaging during thrombectomy on the functional outcomes of patients with large ischemic core (LIC) stroke at both early and late time windows is uncertain in real-world practice. METHOD: A retrospective analysis was performed on 99 patients who underwent computed tomography angiography (CTA) and CT perfusion (CTP)-Rapid Processing of Perfusion and Diffusion (RAPID) before EVT and had a baseline ischemic core ≥ 50 mL and/or Alberta Stroke Program Early CT Score (ASPECTS) score of 0-5. The primary outcome was the three-month modified Rankin Scale (mRS) score. Data were analyzed by binary logistic regression and receiver operating characteristic (ROC) curves. RESULTS: A fair outcome (mRS, 0-3) was found in 34 of the 99 patients while 65 had a poor prognosis (mRS, 4-6). The multivariate logistic regression analysis showed that onset-to-reperfusion (OTR) time (odds ratio [OR], 1.004; 95% confidence interval [CI], 1.001-1.007; p = 0.008), ischemic core (OR, 1.066; 95% CI, 1.024-1.111; p = 0.008), and the hypoperfusion intensity ratio (HIR) (OR, 70.898; 95% CI, 1.130-4450.152; p = 0.044) were independent predictors of outcome. The combined results of ischemic core, HIR, and OTR time showed good performance with an area under the ROC curve (AUC) of 0.937, significantly higher than the individual variables (p < 0.05) using DeLong's test. CONCLUSIONS: Higher HIR and longer OTR time in large core stroke patients were independently associated with unfavorable three-month outcomes after EVT.

[Thrombectomy].

Endovascular procedures have become the standard treatment for acute stroke caused by large vessel occlusion. Various strategies are available, including stent retrieval, aspiration catheter placement, and combined techniques. However, the first-pass effect can be maximized using the technique most familiar to each surgeon and institution. Therefore, it is necessary to understand the characteristics of each device and develop case-specific treatment strategies.

Baseline clinical and neuroradiological predictors of outcome in patients with large ischemic core undergoing mechanical thrombectomy: A retrospective multicenter study.

BACKGROUND: Recent randomized trials have shown the benefit of mechanical thrombectomy (MT) also in patients with an established large ischemic core. AIMS: The purpose of this study was to define baseline predictors of clinical outcome in patients with large vessel occlusion (LVO) in the anterior circulation and an Alberta Stroke Program Early CT score (ASPECTS) ⩽ 5, undergoing MT. MATERIAL AND METHODS: The databases of 16 comprehensive stroke centers were retrospectively screened for patients with LVO and ASPECTS ⩽5 that received MT. Baseline clinical and neuroradiological features, including the differential contribution of all ASPECTS regions to the composite score, were collected. Primary clinical outcome measure was a 90-day modified Rankin Scale (mRS) score of 0-2. Statistical analysis used a logistic regression model and random forest algorithm. RESULTS: A total of 408 patients were available for analysis. In multivariate model, among baseline features, lower age (odd ratio (OR) = 0.962, 95% confidence interval (CI) = 0.943-0.982) and lower National Institute of Health Stroke Scale (NIHSS) score (OR = 0.911, 95% CI = 0.862-0.963) were associated with the mRS score 0-2. Involvement of the M2 (OR = 0.398, 95% CI = 0.206-0.770) or M4 (OR = 0.496, 95% CI = 0.260-0.945) ASPECTS regions was associated with an unfavorable outcome. Random forest analysis confirmed that age and baseline NIHSS score are the most important variables influencing clinical outcome, whereas involvement of cortical regions M5, M4, M2, and M1 can have a negative impact. CONCLUSION: Our retrospective analysis shows that, along with age and baseline clinical impairment, presence of early ischemic changes involving cortical areas has a role in clinical outcome in patients with large ischemic core undergoing MT. DATA ACCESS STATEMENT: The data that support the findings of this study are available upon reasonable request.

Benefit of endovascular treatment for primary versus secondary medium vessel occlusion: A multi-center experience.

AIMS: This study aimed to compare the clinical outcomes and safety of endovascular treatment (EVT) in patients with primary versus secondary medium vessel occlusion (MeVO). METHODS: From the endovascular treatment for acute ischemic stroke in the China registry, we collected consecutive patients with MeVO who received EVT. The primary endpoint was a good outcome, defined as a modified Rankin Scale (mRS) 0 to 2 at 90 days. RESULTS: 154 patients were enrolled in the final analysis, including 74 primary MeVO and 80 secondary MeVO. A good outcome at 90 days was achieved in 42 (56.8%) patients with primary MeVO and 33 (41.3%) patients with secondary MeVO. There was a higher probability of good outcomes in patients with the primary vs secondary MeVO (adjusted odds ratio, 2.16; 95% confidence interval, 1.04 to 4.46; p = 0.04). There were no significant differences in secondary and safety outcomes between MeVO groups. In the multivariable analysis, baseline ASPECTS (p = 0.001), final modified thrombolysis in cerebral infarction score (p = 0.01), and any ICH (p = 0.03) were significantly associated with good outcomes in primary MeVO patients, while baseline National Institutes of Health Stroke Scale (p = 0.002), groin puncture to recanalization time (p = 0.02), and early neurological improvement (p < 0.001) were factors associated with good outcome in secondary MeVO patients. CONCLUSION: In MeVO patients who received EVT, there was a higher likelihood of poor outcomes in patients with secondary versus primary MeVO.

Trajectories of stroke severity and functional outcomes after endovascular treatment in ischemic stroke: A post hoc analysis of a randomized controlled trial.

BACKGROUND: The trajectory of early neurological changes in patients with acute ischemic stroke has been understudied. This study aimed to investigate the association between longitudinal trajectories of stroke severity and 90-day functional outcomes in patients with acute ischemic stroke receiving endovascular treatment. METHODS: We enrolled patients from a prospective, multicenter, randomized controlled trial. The stroke severity was assessed with the National Institute of Health Stroke Scale at the pre-procedure, 24 hours, and seven days after the procedure. Group-based trajectory modeling (GBTM) was used to identify trajectories of stroke severity. Multivariable logistic regression was performed to explore the association between stroke severity markers and 90-day functional outcomes. RESULTS: Of 218 enrolled patients, 127 (58.3%) had poor functional outcomes at 90 days. We identified three trajectories of stroke severity in the GBTM: stable symptom (38.1%), symptom deterioration (17.0%), and symptom improvement (44.9%). In multivariable analyses, trajectories of stroke severity were associated with an increased risk of poor functional outcomes (symptom improvement versus symptom deterioration: odds ratio, 0.007; 95% confidence interval, 0.001-0.040; P <0.001). Reclassification indexes revealed that trajectories of stroke severity would increase the predictive ability for poor functional outcomes at 90 days. CONCLUSION: After endovascular treatment, patients would follow one of three distinct trajectories of stroke severity. Symptom deterioration trajectory was associated with an increased risk of poor functional outcomes at 90 days. TRIAL REGISTRATION NUMBER: NCT04973332.

Status Epilepticus after mechanical thrombectomy: The role of early EEG assessment in Stroke Unit, clinical and radiological prognostication.

BACKGROUND: Convulsive (CSE) and non-convulsive (NCSE) Status Epilepticus are a complication in 0.2-0.3% ischemic strokes. Large stroke and cortical involvement are the main risk factors for developing SE. This study evaluates the prevalence of SE in patients treated with endovascular thrombectomy (EVT) through EEG recording within 72- h from admission. Moreover, we compared clinical, radiological, and outcome measures in SE and no-SE patients. MATERIALS AND METHODS: We collected retrospectively demographical and clinical characteristics of acute ischemic stroke patients who underwent EVT, admitted in the Stroke Unit (SU) of the University Hospital of Trieste between January 2018 and March 2020 who underwent EEG recording within 72- h from the symptoms' onset. RESULTS: Out of 247 EVT patients, 138 met the inclusion criteria, of whom 9 (6.5%) showed SE with median onset time of 1 day (IQR 1-2). No difference was found between the two groups as for age, sex, risk factors, grade of recanalization, etiology of stroke, and closed vessel. The no-SE group presented higher NIHSS improvement rate (p=0.025) compared to the SE group. The sum of the lobes involved in the ischemic lesion was significantly higher in SE group (p=0.048). CONCLUSION: SE after EVT in large strokes is a non-rare complication, with most being NCSE. Performing a rapid EEG assessment in a Stroke Unit setting may allow for a prompt recognition and treatment of SE in the acute/hyper-acute phase. SE may be correlated with worse clinical outcomes in patients with large vessel occlusion.

Peripheral blood syndecan-1 levels after mechanical thrombectomy can predict the clinical prognosis of patients with acute ischemic stroke.

BACKGROUND: Previously, we revealed noticeable dynamic fluctuations in syndecan-1 levels in the peripheral blood of post-stroke patients. We further investigated the clinical prognostic value of syndecan-1 as a biomarker of glycoprotein damage in patients with acute ischaemic stroke (AIS). METHODS: We examined 105 patients with acute large vessel occlusion in the anterior circulation, all of whom underwent mechanical thrombectomy (MT). Peripheral blood syndecan-1 levels were measured 1 day after MT, and patients were categorised into favourable and unfavourable prognostic groups based on the 90-day modified Rankin Scale (mRS) score. Additionally, we compared the clinical outcomes between groups with high and low syndecan-1 concentrations. RESULTS: The findings revealed a significantly lower syndecan-1 level in the group with an unfavourable prognosis compared to those with a favourable prognosis (p < 0.01). In the multivariable logistic regression analysis, lower syndecan-1 levels were identified as a predictor of unfavourable prognosis (odds ratio (OR) = 0.965, p = 0.001). Patients displaying low syndecan-1 expression in the peripheral blood (< 29.51 ng/mL) experienced a > twofold increase in the rates of unfavourable prognosis and mortality. CONCLUSIONS: Our study demonstrates that syndecan-1, as an emerging, easily detectable stroke biomarker, can predict the clinical outcomes of patients with AIS. After MT, low levels of syndecan-1 in the peripheral blood on the first day emerged as an independent risk factor for an unfavourable prognosis, suggesting that lower syndecan-1 levels might signify worse clinical presentation and outcomes in stroke patients undergoing this procedure.

Technical and clinical outcomes of thrombectomy in patients with acute medium vessel occlusion and large vessel occlusion; sub-analyses of Japan Trevo registry.

BACKGROUND: Little is known about endovascular therapy (EVT) for patients with medium vessel occlusion (MeVO) and more work is needed to establish its efficacy and to understand hemorrhagic complications. METHODS: We analyzed the Japan Trevo Registry, which enrolled patients with acute stroke who underwent EVT using Trevo Retriever alone or in combination with an aspiration catheter. The primary outcome was effective reperfusion, and the secondary outcome was modified Rankin scale 0-2 at 90 days. Safety outcomes, including intracranial hemorrhage (ICH), were evaluated using a subgroup analyses focused on any ICH. RESULTS: Among 1041 registered patients, 1025 patients were analyzed. 253 patients had MeVOs, and the majority (89.3%) had middle cerebral artery segment 2 (M2). The median National Institutes of Health Stroke Scale scores at admission were 15 and 19 for the MeVO and LVO groups (p < 0.0001). The primary outcome was 88.9% in MeVO vs. 91.8% in LVO group: adjusted odds ratio (aOR) [95% confidence interval (CI)] 0.60 [0.35-1.03], p = 0.07, and the secondary outcome was 43.2% vs. 42.2%, and the aOR [95%CI] was 0.70 [0.48-1.002], p = 0.051. However, the incidence of any ICH was more prominent in MeVO than in LVO group (35.7% vs. 28.8%, aOR [95%CI] 1.54 [1.10-2.15], p = 0.01). In subgroup analyses, the incidences of any ICH in MeVO group were generally higher than those in LVO group. CONCLUSIONS: The effective reperfusion rate did not differ significantly between MeVO and LVO groups. Future development of devices and treatments for MeVO with fewer hemorrhagic complications is desirable.