Current State of Evidence for Neuroimaging Paradigms in Management of Acute Ischemic Stroke.

Stroke is the chief differential diagnosis in patient presenting to the emergency room with abrupt onset focal neurological deficits. Neuroimaging, including non-contrast computed tomography (CT), magnetic resonance imaging (MRI), vascular and perfusion imaging, is a cornerstone in the diagnosis and treatment decision-making. This review examines the current state of evidence behind the different imaging paradigms for acute ischemic stroke diagnosis and treatment, including current recommendations from the guidelines. Non-contrast CT brain, or in some centers MRI, can help differentiate ischemic stroke and intracerebral hemorrhage (ICH), a pivotal juncture in stroke diagnosis and treatment algorithm, especially for early window thrombolytics. Advanced imaging such as MRI or perfusion imaging can also assist making a diagnosis of ischemic stroke versus mimics such as migraine, Todd's paresis, or functional disorders. Identification of medium-large vessel occlusions with CT or MR angiography triggers consideration of endovascular thrombectomy (EVT), with additional perfusion imaging help identify salvageable brain tissue in patients who are likely to benefit from reperfusion therapies, particularly in the ≥6 h window. We also review recent advances in neuroimaging and ongoing trials in key therapeutic areas and their imaging selection criteria to inform the readers on potential future transitions into use of neuroimaging for stroke diagnosis and treatment decision making. ANN NEUROL 2024;95:1017-1034.

Update of Anticoagulation Use in Cardioembolic Stroke With a Special Reference to Endovascular Treatment.

Cardioembolic stroke is a major cause of morbidity, with a high risk of recurrence, and anticoagulation represents the mainstay of secondary stroke prevention in most patients. The implementation of endovascular treatment in routine clinical practice complicates the decision to initiate anticoagulation, especially in patients with early hemorrhagic transformation who are considered at higher risk of hematoma expansion. Late hemorrhagic transformation in the days and weeks following stroke remains a potentially serious complication for which we still do not have any established clinical or radiological prediction tools. The optimal time to initiate therapy is challenging to define since delaying effective secondary prevention treatment exposes patients to the risk of recurrent embolism. Consequently, there is clinical equipoise to define and individualize the optimal timepoint to initiate anticoagulation combining the lowest risk of hemorrhagic transformation and ischemic recurrence in cardioembolic stroke patients. In this narrative review, we will highlight and critically outline recent observational and randomized relevant evidence in different subtypes of cardioembolic stroke with a special focus on anticoagulation initiation following endovascular treatment. We will refer mainly to the commonest cause of cardioembolism, non-valvular atrial fibrillation, and examine the possible risk and benefit of anticoagulation before, during, and shortly after the acute phase of stroke. Other indications of anticoagulation after ischemic stroke will be briefly discussed. We provide a synthesis of available data to help clinicians individualize the timing of initiation of oral anticoagulation based on the presence and extent of hemorrhagic transformation as well as stroke severity.

Endovascular Thrombectomy Treatment Effect in Direct vs Transferred Patients With Large Ischemic Strokes: A Prespecified Analysis of the SELECT2 Trial.

Importance: Patients with large ischemic core stroke have poor clinical outcomes and are frequently not considered for interfacility transfer for endovascular thrombectomy (EVT). Objective: To assess EVT treatment effects in transferred vs directly presenting patients and to evaluate the association between transfer times and neuroimaging changes with EVT clinical outcomes. Design, Setting, and Participants: This prespecified secondary analysis of the SELECT2 trial, which evaluated EVT vs medical management (MM) in patients with large ischemic stroke, evaluated adults aged 18 to 85 years with acute ischemic stroke due to occlusion of the internal carotid or middle cerebral artery (M1 segment) as well as an Alberta Stroke Program Early CT Score (ASPECTS) of 3 to 5, core of 50 mL or greater on imaging, or both. Patients were enrolled between October 2019 and September 2022 from 31 EVT-capable centers in the US, Canada, Europe, Australia, and New Zealand. Data were analyzed from August 2023 to January 2024. Interventions: EVT vs MM. Main Outcomes and Measures: Functional outcome, defined as modified Rankin Scale (mRS) score at 90 days with blinded adjudication. Results: A total of 958 patients were screened and 606 patients were excluded. Of 352 enrolled patients, 145 (41.2%) were female, and the median (IQR) age was 66.5 (58-75) years. A total of 211 patients (59.9%) were transfers, while 141 (40.1%) presented directly. The median (IQR) transfer time was 178 (136-230) minutes. The median (IQR) ASPECTS decreased from the referring hospital (5 [4-7]) to an EVT-capable center (4 [3-5]). Thrombectomy treatment effect was observed in both directly presenting patients (adjusted generalized odds ratio [OR], 2.01; 95% CI, 1.42-2.86) and transferred patients (adjusted generalized OR, 1.50; 95% CI, 1.11-2.03) without heterogeneity (P for interaction = .14). Treatment effect point estimates favored EVT among 82 transferred patients with a referral hospital ASPECTS of 5 or less (44 received EVT; adjusted generalized OR, 1.52; 95% CI, 0.89-2.58). ASPECTS loss was associated with numerically worse EVT outcomes (adjusted generalized OR per 1-ASPECTS point loss, 0.89; 95% CI, 0.77-1.02). EVT treatment effect estimates were lower in patients with transfer times of 3 hours or more (adjusted generalized OR, 1.15; 95% CI, 0.73-1.80). Conclusions and Relevance: Both directly presenting and transferred patients with large ischemic stroke in the SELECT2 trial benefited from EVT, including those with low ASPECTS at referring hospitals. However, the association of EVT with better functional outcomes was numerically better in patients presenting directly to EVT-capable centers. Prolonged transfer times and evolution of ischemic change were associated with worse EVT outcomes. These findings emphasize the need for rapid identification of patients suitable for transfer and expedited transport. Trial Registration: ClinicalTrials.gov Identifier: NCT03876457.

Endovascular thrombectomy plus medical care versus medical care alone for large ischaemic stroke: 1-year outcomes of the SELECT2 trial.

BACKGROUND: Multiple randomised trials have shown efficacy and safety of endovascular thrombectomy in patients with large ischaemic stroke. The aim of this study was to evaluate long-term (ie, at 1 year) evidence of benefit of thrombectomy for these patients. METHODS: SELECT2 was a phase 3, open-label, international, randomised controlled trial with blinded endpoint assessment, conducted at 31 hospitals in the USA, Canada, Spain, Switzerland, Australia, and New Zealand. Patients aged 18-85 years with ischaemic stroke due to proximal occlusion of the internal carotid artery or of the first segment of the middle cerebral artery, showing large ischaemic core on non-contrast CT (Alberta Stroke Program Early Computed Tomographic Score of 3-5 [range 0-10, with lower values indicating larger infarctions]) or measuring 50 mL or more on CT perfusion and MRI, were randomly assigned, within 24 h of ischaemic stroke onset, to thrombectomy plus medical care or to medical care alone. The primary outcome for this analysis was the ordinal modified Rankin Scale (range 0-6, with higher scores indicating greater disability) at 1-year follow-up in an intention-to-treat population. The trial is registered at ClinicalTrials.gov (NCT03876457) and is completed. FINDINGS: The trial was terminated early for efficacy at the 90-day follow-up after 352 patients had been randomly assigned (178 to thrombectomy and 174 to medical care only) between Oct 11, 2019, and Sept 9, 2022. Thrombectomy significantly improved the 1-year modified Rankin Scale score distribution versus medical care alone (Wilcoxon-Mann-Whitney probability of superiority 0·59 [95% CI 0·53-0·64]; p=0·0019; generalised odds ratio 1·43 [95% CI 1·14-1·78]). At the 1-year follow-up, 77 (45%) of 170 patients receiving thrombectomy had died, compared with 83 (52%) of 159 patients receiving medical care only (1-year mortality relative risk 0·89 [95% CI 0·71-1·11]). INTERPRETATION: In patients with ischaemic stroke due to a proximal occlusion and large core, thrombectomy plus medical care provided a significant functional outcome benefit compared with medical care alone at 1-year follow-up. FUNDING: Stryker Neurovascular.

Endovascular Thrombectomy for Large Ischemic Stroke Across Ischemic Injury and Penumbra Profiles.

Importance: Whether endovascular thrombectomy (EVT) efficacy for patients with acute ischemic stroke and large cores varies depending on the extent of ischemic injury is uncertain. Objective: To describe the relationship between imaging estimates of irreversibly injured brain (core) and at-risk regions (mismatch) and clinical outcomes and EVT treatment effect. Design, Setting, and Participants: An exploratory analysis of the SELECT2 trial, which randomized 352 adults (18-85 years) with acute ischemic stroke due to occlusion of the internal carotid or middle cerebral artery (M1 segment) and large ischemic core to EVT vs medical management (MM), across 31 global centers between October 2019 and September 2022. Intervention: EVT vs MM. Main Outcomes and Measures: Primary outcome was functional outcome-90-day mRS score (0, no symptoms, to 6, death) assessed by adjusted generalized OR (aGenOR; values >1 represent more favorable outcomes). Benefit of EVT vs MM was assessed across levels of ischemic injury defined by noncontrast CT using ASPECTS score and by the volume of brain with severely reduced blood flow on CT perfusion or restricted diffusion on MRI. Results: Among 352 patients randomized, 336 were analyzed (median age, 67 years; 139 [41.4%] female); of these, 168 (50%) were randomized to EVT, and 2 additional crossover MM patients received EVT. In an ordinal analysis of mRS at 90 days, EVT improved functional outcomes compared with MM within ASPECTS categories of 3 (aGenOR, 1.71 [95% CI, 1.04-2.81]), 4 (aGenOR, 2.01 [95% CI, 1.19-3.40]), and 5 (aGenOR, 1.85 [95% CI, 1.22-2.79]). Across strata for CT perfusion/MRI ischemic core volumes, aGenOR for EVT vs MM was 1.63 (95% CI, 1.23-2.16) for volumes ≥70 mL, 1.41 (95% CI, 0.99-2.02) for ≥100 mL, and 1.47 (95% CI, 0.84-2.56) for ≥150 mL. In the EVT group, outcomes worsened as ASPECTS decreased (aGenOR, 0.91 [95% CI, 0.82-1.00] per 1-point decrease) and as CT perfusion/MRI ischemic core volume increased (aGenOR, 0.92 [95% CI, 0.89-0.95] per 10-mL increase). No heterogeneity of EVT treatment effect was observed with or without mismatch, although few patients without mismatch were enrolled. Conclusion and Relevance: In this exploratory analysis of a randomized clinical trial of patients with extensive ischemic stroke, EVT improved clinical outcomes across a wide spectrum of infarct volumes, although enrollment of patients with minimal penumbra volume was low. In EVT-treated patients, clinical outcomes worsened as presenting ischemic injury estimates increased. Trial Registration: ClinicalTrials.gov Identifier: NCT03876457.

Blood Pressure Trajectories and Outcomes After Endovascular Thrombectomy for Acute Ischemic Stroke.

BACKGROUND: Data on systolic blood pressure (SBP) trajectories in the first 24 hours after endovascular thrombectomy (EVT) in acute ischemic stroke are limited. We sought to identify these trajectories and their relationship to outcomes. METHODS: We combined individual-level data from 5 studies of patients with acute ischemic stroke who underwent EVT and had individual blood pressure values after the end of the procedure. We used group-based trajectory analysis to identify the number and shape of SBP trajectories post-EVT. We used mixed effects regression models to identify associations between trajectory groups and outcomes adjusting for potential confounders and reported the respective adjusted odds ratios (aORs) and common odds ratios. RESULTS: There were 2640 total patients with acute ischemic stroke included in the analysis. The most parsimonious model identified 4 distinct SBP trajectories, that is, general directional patterns after repeated SBP measurements: high, moderate-high, moderate, and low. Patients in the higher blood pressure trajectory groups were older, had a higher prevalence of vascular risk factors, presented with more severe stroke syndromes, and were less likely to achieve successful recanalization after the EVT. In the adjusted analyses, only patients in the high-SBP trajectory were found to have significantly higher odds of early neurological deterioration (aOR, 1.84 [95% CI, 1.20-2.82]), intracranial hemorrhage (aOR, 1.84 [95% CI, 1.31-2.59]), mortality (aOR, 1.75 [95% CI, 1.21-2.53), death or disability (aOR, 1.63 [95% CI, 1.15-2.31]), and worse functional outcomes (adjusted common odds ratio,1.92 [95% CI, 1.47-2.50]). CONCLUSIONS: Patients follow distinct SBP trajectories in the first 24 hours after an EVT. Persistently elevated SBP after the procedure is associated with unfavorable short-term and long-term outcomes.

Is thrombectomy indicated in all ischemic stroke with large vessel occlusion?

PURPOSE OF REVIEW: Purpose of this topical review is to examine the current randomized and nonrandomized evidence evaluating endovascular thrombectomy (EVT) in selected patient populations with acute ischemic stroke due to large vessel occlusions. RECENT FINDINGS: After establishing EVT as the first-line treatment in patients with large vessel occlusions and limited ischemic changes on neuroimaging, recent trials successfully demonstrated efficacy and safety in patients with large core strokes and those with basilar occlusions up to 24 h of last known well. Nonrandomized evidence in patients with mild stroke severity, baseline disability, medium and distal vessel occlusions and time from last known well >24 h also suggested potential benefit of EVT in selected patients. Further randomized evidence will help establish EVT efficacy and safety in these populations. SUMMARY: EVT is established as the de-facto treatment of choice in a significant proportion of patients presenting with acute ischemic stroke due to a large vessel occlusion and has shown potential benefits in additional patient subgroups. A rigorous risk-benefit assessment and discussions with patients and their families in the absence of randomized evidence should help facilitate an informed, individualized decision-making process for this revolutionary treatment in peripheral patient subgroups with limited evidence.

Association between blood pressure variability and outcomes after endovascular thrombectomy for acute ischemic stroke: An individual patient data meta-analysis.

INTRODUCTION: Data on the association between blood pressure variability (BPV) after endovascular thrombectomy (EVT) for acute ischemic stroke (AIS) and outcomes are limited. We sought to identify whether BPV within the first 24 hours post EVT was associated with key stroke outcomes. METHODS: We combined individual patient-data from five studies among AIS-patients who underwent EVT, that provided individual BP measurements after the end of the procedure. BPV was estimated as either systolic-BP (SBP) standard deviation (SD) or coefficient of variation (CV) over 24 h post-EVT. We used a logistic mixed-effects model to estimate the association [expressed as adjusted odds ratios (aOR)] between tertiles of BPV and outcomes of 90-day mortality, 90-day death or disability [modified Rankin Scale-score (mRS) > 2], 90-day functional impairment (⩾1-point increase across all mRS-scores), and symptomatic intracranial hemorrhage (sICH), adjusting for age, sex, stroke severity, co-morbidities, pretreatment with intravenous thrombolysis, successful recanalization, and mean SBP and diastolic-BP levels within the first 24 hours post EVT. RESULTS: There were 2640 AIS-patients included in the analysis. The highest tertile of SBP-SD was associated with higher 90-day mortality (aOR:1.44;95% CI:1.08-1.92), 90-day death or disability (aOR:1.49;95% CI:1.18-1.89), and 90-day functional impairment (adjusted common OR:1.42;95% CI:1.18-1.72), but not with sICH (aOR:1.22;95% CI:0.76-1.98). Similarly, the highest tertile of SBP-CV was associated with higher 90-day mortality (aOR:1.33;95% CI:1.01-1.74), 90-day death or disability (aOR:1.50;95% CI:1.19-1.89), and 90-day functional impairment (adjusted common OR:1.38;95% CI:1.15-1.65), but not with sICH (aOR:1.33;95% CI:0.83-2.14). CONCLUSIONS: BPV after EVT appears to be associated with higher mortality and disability, independently of mean BP levels within the first 24 h post EVT. BPV in the first 24 h may be a novel target to improve outcomes after EVT for AIS.

Endovascular therapy versus best medical management for isolated posterior cerebral artery occlusion: A systematic review and meta-analysis.

BACKGROUND AND PURPOSE: Isolated posterior cerebral artery occlusions (iPCAO) were underrepresented in pivotal randomized clinical trial (RCTs) of endovascular thrombectomy (EVT) in ischemic stroke, and the benefit of EVT in this population is still indeterminate. We performed a systematic review and a meta-analysis to compare the safety and efficacy of EVT compared to best medical management (BMM) in patients with iPCAO. METHODS: We searched Medline/PubMed, Embase, Web of Science, and the Cochrane databases up to May 2023 for eligible studies reporting outcomes of patients with iPCAO treated with EVT or BMM. We pooled odds ratios (ORs) with corresponding 95% confidence intervals (CI) using a random-effects model. RESULTS: Seven studies involving 2560 patients were included. EVT was associated with significantly higher likelihood of early neurological improvement (OR, 2.31 [95% CI, 1.38-2.91]; p < 0.00001) and visual field normalization (OR, 3.08 [95% CI, 1.76-5.38]; p < 0.0001) compared to BMM. Rates of good functional outcomes (mRS 0-2) were comparable between the two arms (OR, 0.88 [95% CI, 0.70-1.10]; p = 0.26). Symptomatic intracranial hemorrhage (sICH) was comparable between the two groups (OR, 1.94 [95% CI, 0.96-3.93]; p = 0.07). Mortality was also similar between the two groups (OR, 1.36; [95% CI, 0.77-2.42]; p = 0.29). CONCLUSIONS: In patients with iPCAO, EVT was associated with visual and early neurological improvement but with a strong trend toward increased sICH. Survival and functional outcomes may be slightly poorer. The role of EVT in iPCAO remains uncertain.

Medical Management Versus Endovascular Treatment for Large-Vessel Occlusion Anterior Circulation Stroke With Low NIHSS.

BACKGROUND: Endovascular treatment (EVT) for acute ischemic stroke (AIS) patients presenting with National Institutes of Health Stroke Scale score of 0 to 5 is common in clinical practice but has not yet been proven safe and effective. Our objective is to assess whether EVT on top of best medical treatment (BMT) in AIS patients with large-vessel occlusion of the anterior circulation presenting with mild symptoms is beneficial compared with BMT. METHODS: We searched MEDLINE, SCOPUS, and reference lists of retrieved articles published until December 28, 2022. A systematic literature search was conducted to identify clinical trials or observational cohort studies evaluating patients with AIS due to anterior circulation large-vessel occlusion and admission National Institutes of Health Stroke Scale score ≤5 treated with EVT versus BMT alone. The primary outcome was excellent functional outcome (modified Rankin Scale score 0-1) at 3 months. The protocol had been registered before data collection (PROSPERO). RESULTS: Eleven observational eligible studies were included in the meta-analysis, comprising a total of 2019 AIS patients with National Institutes of Health Stroke Scale score ≤5 treated with EVT versus 3171 patients treated with BMT. EVT was not associated with excellent functional outcome (risk ratio, 1.10 [95% CI, 0.93-1.31]). When stratified for different study design (per-protocol versus intention-to-treat), there were no significant subgroup differences. EVT was not associated with good functional outcome (modified Rankin Scale score 0-2; risk ratio, 1.01 [95% CI, 0.89-1.16]) or reduced disability at 3 months (common odds ratio, 0.92 [95% CI, 0.60-1.41]). Symptomatic intracranial hemorrhage was more common in the patients receiving EVT (risk ratio, 3.53 [95% CI, 2.35-5.31]). No correlation was found between EVT and mortality at 3 months (risk ratio, 1.34 [95% CI, 0.83-2.18]). The same overall associations were confirmed in the sensitivity analysis of studies that performed propensity score matching. CONCLUSIONS: EVT appears equivalent to BMT for patients with anterior circulation large-vessel occlusion AIS with low baseline National Institutes of Health Stroke Scale, despite the increased risk for symptomatic intracranial hemorrhage. REGISTRATION: URL: https://www.crd.york.ac.uk/PROSPERO/; Unique identifier: CRD42022334417.

Endovascular treatment for large-core ischaemic stroke: a meta-analysis of randomised controlled clinical trials.

BACKGROUND AND PURPOSE: Current guidelines recommend endovascular treatment (EVT) for acute ischaemic stroke (AIS), due to large-vessel occlusion and an Alberta Stroke Program Early CT Score (ASPECTS) of ≥6. High-quality evidence resulting from randomised controlled clinical trials (RCTs) regarding EVT among large-core AIS has recently become available, justifying an updated meta-analysis aiming to evaluate efficacy and safety of EVT in this clinical setting. METHODS: We conducted a systematic review and meta-analysis including all available RCTs that compared EVT in addition to best medical treatment (BMT) versus BMT alone for large-core AIS (defined by ASPECTS 2-5 or volumetric methods). The primary outcome was reduced disability at 3 months (≥1-point reduction across all Modified Rankin Scale (mRS) grades). Secondary outcomes included independent ambulation at 3 months (mRS score 0-3), good functional outcome at 3 months (mRS score 0-2), excellent functional outcome at 3 months (mRS score 0-1), symptomatic intracranial haemorrhage (sICH) and any intracranial haemorrhage (ICH) and mortality at 3 months. The random-effects model was used. RESULTS: Four RCTs were included comprising a total of 662 patients treated with EVT vs 649 patients treated with BMT. Compared with BMT, EVT was significantly associated with reduced disability (common OR 1.70, 95% CI 1.39 to 2.07; I2=0%), independent ambulation (risk ratio (RR) 1.69, 95% CI 1.33 to 2.14; I2=39%) and good functional outcome (RR 2.33, 95% CI 1.76 to 3.10; I2=0%), but not with excellent functional outcome (RR 1.46, 95% CI 0.91 to 2.33; I2=39%) at 3 months. Although rates of sICH (RR 1.98, 95% CI 1.07 to 3.68; I2=0%) and any ICH (RR 2.13, 95% CI 1.70 to 2.66; I2=37%) were higher in the EVT group, 3-month mortality (RR 0.98, 95% CI 0.83 to 1.15; I2=0%) did not differ between the two groups. CONCLUSION: EVT appears to be effective and safe and may be considered for the treatment of large-core AIS, as assessed by ASPECTS of 2-5 or volumetric methods. PROSPERO REGISTRATION NUMBER: CRD42022334417.

Mechanical Thrombectomy for Large Ischemic Stroke: A Systematic Review and Meta-analysis.

BACKGROUND AND OBJECTIVES: There is growing evidence for endovascular thrombectomy (EVT) in patients with large ischemic core infarct and large vessel occlusion (LVO). The objective of this study was to compare the efficacy and safety of EVT vs medical management (MM) using a systematic review and meta-analysis of observational studies and randomized controlled trials (RCTs). METHODS: We searched the PubMed, Embase, Cochrane Library, and Web of Science databases to obtain articles related to mechanical thrombectomy for large ischemic core from inception until February 10, 2023. The primary outcome was independent ambulation (modified Rankin Scale [mRS] 0-3). Effect sizes were computed as risk ratio (RR) with random-effect or fixed-effect models. The quality of articles was evaluated through the Cochrane risk assessment tool and the Newcastle-Ottawa Scale. This study was registered in PROSPERO (CRD42023396232). RESULTS: A total of 5,395 articles were obtained through the search and articles that did not meet the inclusion criteria were excluded by review of the title, abstract, and full text. Finally, 3 RCTs and 10 cohort studies met the inclusion criteria. The RCT analysis showed that EVT improved the 90-day functional outcomes of patients with large ischemic core with high-quality evidence, including independent ambulation (mRS 0-3: RR 1.78, 95% CI 1.28-2.48, p < 0.001) and functional independence (mRS 0-2: RR 2.59, 95% CI 1.89-3.57, p < 0.001), but without significantly increasing the risk of symptomatic intracranial hemorrhage (sICH: RR 1.83, 95% CI 0.95-3.55, p = 0.07) or early mortality (RR 0.95, 95% CI 0.78-1.16, p = 0.61). Analysis of the cohort studies showed that EVT improved functional outcomes of patients without an increase in the incidence in sICH. DISCUSSION: This systematic review and meta-analysis indicates that in patients with LVO stroke with a large ischemic core, EVT was associated with improved functional outcomes over MM without increasing sICH risk. The results of ongoing RCTs may provide further insight in this patient population.

Endovascular thrombectomy beyond 24 hours from last known well: a systematic review with meta-analysis.

BACKGROUND: Different studies have demonstrated the benefit of endovascular treatment (EVT) up to 24 hours after acute ischemic stroke (AIS) onset. Recent cohort observational studies suggest that patients with large vessel occlusion AIS may benefit from EVT beyond 24 hours from the last known well (LKW) when adequately selected. We aimed to examine the safety and efficacy of EVT beyond 24 hours from LKW using a meta-analysis of all the literature available. METHODS: A systematic search from inception to April 2023 was conducted for studies including AIS patients with EVT beyond 24 hours from LKW in Medline, Embase, Scopus, and Web of Science. Outcomes of interest included favorable functional outcome (90-day modified Rankin scale (mRS) 0-2), successful reperfusion (modified Thrombolysis in Cerebral Infarction (mTICI) 2b-3), symptomatic intracerebral hemorrhage (sICH), and 90-day mortality. Data were pooled using a random-effects model. RESULTS: Twelve studies with 894 patients were included. The rate of favorable functional outcome was 40% (95% CI 31% to 49%; I2=76%). The rate of successful reperfusion was 83% (95% CI 80% to 85%; I2=0%). The sICH rate was 7% (95% CI 5% to 9%; I2=0%) and the 90-day mortality rate was 28% (95% CI 24% to 33%; I2=0%). There was no significant difference in favorable outcomes (OR=0.69; 95% CI 0.41 to 1.14) and 90-day mortality (OR=1.35; 95% CI 0.90 to 2.00) among patients who underwent EVT <24 hours versus >24 hours. CONCLUSIONS: EVT beyond 24 hours from LKW may achieve favorable clinical outcomes and high reperfusion rates, with acceptable intracranial hemorrhage rates in selected patients. Considering the current certainty of the evidence and heterogenous individual study results, larger prospective trials are warranted.

Trial of Endovascular Thrombectomy for Large Ischemic Strokes.

BACKGROUND: Trials of the efficacy and safety of endovascular thrombectomy in patients with large ischemic strokes have been carried out in limited populations. METHODS: We performed a prospective, randomized, open-label, adaptive, international trial involving patients with stroke due to occlusion of the internal carotid artery or the first segment of the middle cerebral artery to assess endovascular thrombectomy within 24 hours after onset. Patients had a large ischemic-core volume, defined as an Alberta Stroke Program Early Computed Tomography Score of 3 to 5 (range, 0 to 10, with lower scores indicating larger infarction) or a core volume of at least 50 ml on computed tomography perfusion or diffusion-weighted magnetic resonance imaging. Patients were assigned in a 1:1 ratio to endovascular thrombectomy plus medical care or to medical care alone. The primary outcome was the modified Rankin scale score at 90 days (range, 0 to 6, with higher scores indicating greater disability). Functional independence was a secondary outcome. RESULTS: The trial was stopped early for efficacy; 178 patients had been assigned to the thrombectomy group and 174 to the medical-care group. The generalized odds ratio for a shift in the distribution of modified Rankin scale scores toward better outcomes in favor of thrombectomy was 1.51 (95% confidence interval [CI], 1.20 to 1.89; P<0.001). A total of 20% of the patients in the thrombectomy group and 7% in the medical-care group had functional independence (relative risk, 2.97; 95% CI, 1.60 to 5.51). Mortality was similar in the two groups. In the thrombectomy group, arterial access-site complications occurred in 5 patients, dissection in 10, cerebral-vessel perforation in 7, and transient vasospasm in 11. Symptomatic intracranial hemorrhage occurred in 1 patient in the thrombectomy group and in 2 in the medical-care group. CONCLUSIONS: Among patients with large ischemic strokes, endovascular thrombectomy resulted in better functional outcomes than medical care but was associated with vascular complications. Cerebral hemorrhages were infrequent in both groups. (Funded by Stryker Neurovascular; SELECT2 ClinicalTrials.gov number, NCT03876457.).

Sex differences in endovascular thrombectomy outcomes in large vessel occlusion: a propensity-matched analysis from the SELECT study.

BACKGROUND: Sex disparities in acute ischemic stroke outcomes are well reported with IV thrombolysis. Despite several studies, there is still a lack of consensus on whether endovascular thrombectomy (EVT) outcomes differ between men and women. OBJECTIVE: To compare sex differences in EVT outcomes at 90-day follow-up and assess whether progression in functional status from discharge to 90-day follow-up differs between men and women. METHODS: From the Selection for Endovascular Treatment in Acute Ischemic Stroke (SELECT) prospective cohort study (2016-2018), adult men and women (≥18 years) with anterior circulation large vessel occlusion (internal carotid artery, middle cerebral artery M1/M2) treated with EVT up to 24 hours from last known well were matched using propensity scores. Discharge and 90-day modified Rankin Scale (mRS) scores were compared between men and women. Furthermore, we evaluated the improvement in mRS scores from discharge to 90 days in men and women using a repeated-measures, mixed-effects regression model. RESULTS: Of 285 patients, 139 (48.8%) were women. Women were older with median (IQR) age 69 (57-81) years vs 64.5 (56-75), p=0.044, had smaller median perfusion deficits (Tmax >6 s) 109 vs 154 mL (p<0.001), and had better collaterals on CT angiography and CT perfusion but similar ischemic core size (relative cerebral blood flow <30%: 7.6 (0-25.2) vs 11.4 (0-38) mL, p=0.22). In 65 propensity-matched pairs, despite similar discharge functional independence rates (women: 42% vs men: 48%, aOR=0.55, 95% CI 0.18 to 1.69, p=0.30), women exhibited worse 90-day functional independence rates (women: 46% vs men: 60%, aOR=0.41, 95% CI 0.16 to 1.00, p=0.05). The reduction in mRS scores from discharge to 90 days also demonstrated a significantly larger improvement in men (discharge 2.49 and 90 days 1.88, improvement 0.61) than in women (discharge 2.52 and 90 days 2.44, improvement 0.08, p=0.036). CONCLUSION: In a propensity-matched cohort from the SELECT study, women had similar discharge outcomes as men following EVT, but the improvement from discharge to 90 days was significantly worse in women, suggesting the influence of post-discharge factors. Further exploration of this phenomenon to identify target interventions is warranted. TRIAL REGISTRATION NUMBER: NCT02446587.

Higher number of stent-retriever thrombectomy passes significantly increases risk of mass effect, poor functional outcome, and mortality.

INTRODUCTION: Endovascular treatment (EVT) is a widely proven method to treat patients diagnosed with intracranial large vessel occlusion (LVO). Through this method of treatment, it has been hypothesized that a lower number of thrombectomy passes is an indicator of higher rates of modified Thrombolysis in Cerebral Infarction 2B-3 (mTICI) reperfusion and favorable outcomes at 90-days defined as modified Rankin Scale 0-2 (mRS). METHODS: Through the utilization of a prospectively collected endovascular database between 2012-2020, variables such as demographics, co-morbid conditions, intracerebral hemorrhage, mass effect, mortality rate, and good/poor outcomes regarding mTICI score and mRS assessment at 90-days were examined. The outcomes between patients receiving EVT who were treated with < 3 thrombectomy passes or ≥3 passes were compared. RESULTS: Out of 454 patients treated with mechanical thrombectomy of qualifying intracranial internal carotid artery (ICA) or middle cerebral artery occlusion, site of occlusion (ICA, ICA-T M1, and M2/M3), a total of 372 (81.9%) were treated with < 3 passes (average age 70.34 ± 13.75 years, 46.0% women), and 82 (18.1%) were treated with ≥3 passes (average age 70.30 ± 13.72 years, 48.8% women). Significantly higher rates of mass effect (p = 0.043), mRS score 3-6 (p = 0.029), mortality (p = 0.025), and poor reperfusion (p < 0.0001) were noted in patients treated with ≥3 passes. CONCLUSION: A higher number of thrombectomy passes, characterized as ≥3 in this study, was associated with significantly worsened patient outcome regarding mRS and mortality. Further research is required to determine whether the number of thrombectomy passes is an accurate predictor of treatment outcome.