Basilar artery occlusion management: An international survey of gender influence on management.

BACKGROUND: The superiority of endovascular thrombectomy (EVT) over medical management was not established in two early basilar artery occlusion (BAO) randomized controlled trials. Despite this, many clinicians recommended EVT for acute BAO under certain circumstances. This paper aims to compare physicians' diagnostic and management strategies of BAO according to gender. METHODS: From January to March 2022 an international survey was conducted regarding management strategies in acute BAO. We compared responses between clinicians by identifying gender. Questions were designed to examine clinical and imaging parameters influencing management of patients with BAO. RESULTS: Among the 1245 respondents from 73 countries, 311 (25.0%) identified as female. This figure was 13.6% amongst interventionists. Geographically, female respondents were lowest in Asia (14.5%) and North America (23.9%). The proportion of respondents identifying as female was consistent regardless of their years of experience. Female respondents were more likely to choose time of onset as time of first estimated stroke like symptom (48.0% vs. 38.5%, p < .01), were less likely to favor thrombectomy in the V4 segment of vertebrobasilar artery occlusions (31.5% vs. 43.3%, p < .01), and were less likely to find it acceptable to enroll all patients who met trial criteria in the standard medical treatment arm of a clinical trial (41.2% vs. 47.0%, p = .01). Male respondents were more likely to agree that thrombolysis would not alter their decision on proceeding with EVT (93.7% vs. 88.3%, p < .01). CONCLUSIONS: Female clinicians appear to be significantly underrepresented in stroke medicine. This is most pronounced amongst interventionists and in Asia. Although male and female opinions were closely aligned on many aspects of BAO management, differences in opinion were observed in a number of significant areas which influence decision making.

Association of first-line thrombectomy technique and outcome in late-window large vessel occlusion strokes: A post hoc analysis of the MR CLEAN-LATE trial.

BACKGROUND: This study aimed to compare direct aspiration, stent retriever, and the combined thrombectomy technique on clinical, safety, and technical outcomes in late-window stroke patients included in the MR CLEAN-LATE trial. METHODS: This post hoc analysis of the MR CLEAN-LATE trial included patients treated with direct aspiration, stent retriever, or combined thrombectomy technique as first-line approach. Primary outcome was the modified Rankin Scale (mRS) score at 90 days follow-up, and compared between the three groups with ordinal logistic regression analysis. Secondary outcomes included mortality at 90 days, total technique switches, procedure time, recanalization rate measured with the expanded thrombolysis in cerebral infarction (eTICI) score, and symptomatic intracranial hemorrhage (sICH). Predefined variables were used for adjustments. RESULTS: In the MR CLEAN-LATE trial, 258 patients underwent endovascular treatment and 232 were included in our analyses. The mRS at 90 days did not differ (stent retriever vs. direct aspiration: adjusted common odds ratio (acOR) = 1.35, 95% confidence interval (CI) = 0.73 to 2.50; stent retriever vs. combined: acOR = 1.13, 95% CI = 0.64 to 2.00; direct aspiration vs. combined: acOR = 1.19, 95% CI = 0.64 to 2.21). Direct aspiration thrombectomy was accompanied with more switches to another technique compared to the stent retriever (adjusted odds ratio (aOR) = 6.50, 95% CI = 2.52 to 16.8) or combined group (aOR = 4.67, 95% CI = 1.80 to 12.1) and with higher sICH rates compared to the combined technique (13% vs. 2.5%; aOR = 8.19, 95% CI = 1.49 to 45.1). Mortality, procedure time, and eTICI did not differ. CONCLUSION: Stent retriever, direct aspiration, or the combined thrombectomy technique as first-line approach showed no differences in clinical outcome in late-window stroke patients. Direct aspiration was accompanied with higher sICH rates and more switcher to another technique compared to the combined group.

Safety and efficacy of active blood-pressure reduction to the recommended thresholds for intravenous thrombolysis in patients with acute ischaemic stroke in the Netherlands (TRUTH): a prospective, observational, cluster-based, parallel-group study.

BACKGROUND: Intravenous thrombolysis is contraindicated in patients with ischaemic stroke with blood pressure higher than 185/110 mm Hg. Prevailing guidelines recommend to actively lower blood pressure with intravenous antihypertensive agents to allow for thrombolysis; however, there is no robust evidence for this strategy. Because rapid declines in blood pressure can also adversely affect clinical outcomes, several Dutch stroke centres use a conservative strategy that does not involve the reduction of blood pressure. We aimed to compare the clinical outcomes of both strategies. METHODS: Thrombolysis and Uncontrolled Hypertension (TRUTH) was a prospective, observational, cluster-based, parallel-group study conducted across 37 stroke centres in the Netherlands. Participating centres had to strictly adhere to an active blood-pressure-lowering strategy or to a non-lowering strategy. Eligible participants were adults (≥18 years) with ischaemic stroke who had blood pressure higher than 185/110 mm Hg but were otherwise eligible for intravenous thrombolysis. The primary outcome was functional status at 90 days, measured using the modified Rankin Scale and assessed through telephone interviews by trained research nurses. Secondary outcomes were symptomatic intracranial haemorrhage, the proportion of patients treated with intravenous thrombolysis, and door-to-needle time. All ordinal logistic regression analyses were adjusted for age, sex, stroke severity, endovascular thrombectomy, and baseline imbalances as fixed-effect variables and centre as a random-effect variable to account for the clustered design. Analyses were done according to the intention-to-treat principle, whereby all patients were analysed according to the treatment strategy of the participating centre at which they were treated. FINDINGS: Recruitment began on Jan 1, 2015, and was prematurely halted because of a declining inclusion rate and insufficient funding on Jan 5, 2022. Between these dates, we recruited 853 patients from 27 centres that followed an active blood-pressure-lowering strategy and 199 patients from ten centres that followed a non-lowering strategy. Baseline characteristics of participants from the two groups were similar. The 90-day mRS score was missing for 15 patients. The adjusted odds ratio (aOR) for a shift towards a worse 90-day functional outcome was 1·27 (95% CI 0·96-1·68) for active blood-pressure reduction compared with no active blood-pressure reduction. 798 (94%) of 853 patients in the active blood-pressure-lowering group were treated with intravenous thrombolysis, with a median door-to-needle time of 35 min (IQR 25-52), compared with 104 (52%) of 199 patients treated in the non-lowering group with a median time of 47 min (29-78). 42 (5%) of 852 patients in the active blood-pressure-lowering group had a symptomatic intracranial haemorrhage compared with six (3%) of 199 of those in the non-lowering group (aOR 1·28 [95% CI 0·62-2·62]). INTERPRETATION: Insufficient evidence was available to establish a difference between an active blood-pressure-lowering strategy-in which antihypertensive agents were administered to reduce blood pressure below 185/110 mm Hg-and a non-lowering strategy for the functional outcomes of patients with ischaemic stroke, despite higher intravenous thrombolysis rates and shorter door-to-needle times among those in the active blood-pressure-lowering group. Randomised controlled trials are needed to inform the use of an active blood-pressure-lowering strategy. FUNDING: Fonds NutsOhra.

Posterior circulation collaterals as predictors of outcome in basilar artery occlusion: a sub-analysis of the BASICS randomized trial.

Introduction and purpose: Basilar artery occlusion (BAO) is still one of the most devastating neurological conditions associated with high morbidity and mortality. In the present study, we aimed to assess the role of posterior circulation collaterals as predictors of outcome in the BASICS trial and to compare two grading systems (BATMAN score and PC-CS) in terms of prognostic value. Methods: We performed a sub-analysis of the BASICS trial. Baseline clinical and imaging variables were analyzed. For the imaging analysis, baseline CT and CTA were analyzed by a central core lab. Only those patients with good or moderate quality of baseline CTA and with confirmed BAO were included. Multivariable binary logistic regression analysis was used to test the independent association of clinical and imaging characteristics with a favorable outcome at 3 months (defined as a modified Rankin Score of ≤3). ROC curve analysis was used to assess and compare accuracy between the two collateral grading systems. Results: The mean age was 67.0 (±12.5) years, 196 (65.3%) patients were males and the median NIHSS was 21.5 (IQR 11-35). Median NCCT pc-ASPECTS was 10 (IQR10-10) and median collateral scores for BATMAN and PC-CS were 8 (IQR 7-9) and 7 (IQR 6-8) respectively. Collateral scores were associated with favorable outcome at 3 months for both BATMAN and PC-CS but only with a modest accuracy on ROC curve analysis (AUC 0.62, 95% CI [0.55-0.69] and 0.67, 95% CI [0.60-0.74] respectively). Age (OR 0.97, 95% CI [0.95-1.00]), NIHSS (OR 0.91, 95% CI [0.89-0.94]) and collateral score (PC-CS - OR 1.2495% CI [1.02-1.51]) were independently associated with clinical outcome. Conclusion: The two collateral grading systems presented modest prognostic accuracy. Only the PC-CS was independently associated with a favorable outcome at 3 months.

Endovascular thrombectomy with versus without intravenous thrombolysis in patients with acute basilar artery occlusion: a systematic review and meta-analysis.

BACKGROUND AND PURPOSE: The benefit and safety of intravenous thrombolysis before endovascular thrombectomy in patients with acute ischemic stroke caused by basilar artery occlusion (BAO) remains unclear. This article aims to investigate the clinical outcomes and safety of endovascular thrombectomy with versus without intravenous thrombolysis in acute BAO stroke patients. METHODS: We conducted a comprehensive search of PubMed, Embase, Cochrane, and Web of Science databases to identify relevant literature pertaining to patients with acute BAO who underwent endovascular thrombectomy alone or intravenous thrombolysis bridging with endovascular thrombectomy (bridging therapy), until January 10, 2024. The primary outcome was functional independence, defined as a score of 0-2 on the modified Rankin Scale at 90 days. The safety outcome was mortality at 90 days and symptomatic intracranial hemorrhage within 48 h. Effect sizes were computed as risk ratio (RR) with random-effect models. This study was registered in PROSPERO (CRD42023462293). RESULTS: A total of 528 articles were obtained through the search and articles that did not meet the inclusion criteria were excluded. Finally, 2 RCTs and 10 cohort studies met the inclusion criteria. The findings revealed that the endovascular thrombectomy alone group had a lower rate of functional independence compared to the bridging therapy group (29% vs 38%; RR 0.78, 95% CI 0.68-0.88, p < 0.001), lower independent ambulation (39% vs 45%; RR 0.89, 95% CI 0.82-0.98, p = 0.01), and higher mortality (36% vs 28%, RR 1.22, 95% CI 1.08-1.37, p = 0.001). However, no differences were detected in symptomatic intracranial hemorrhage between the two groups (6% vs 4%; RR 1.12, 95% CI 0.74-1.71, p = 0.58). CONCLUSION: Intravenous thrombolysis plus endovascular thrombectomy seemed to led to better functional independence, independent ambulation, and lower risk of mortality without increasing the incidence of intracranial hemorrhage compared to endovascular thrombectomy alone. However, given the non-randomized nature of this study, further studies are needed to confirm these findings.

Sex differences in clot, vessel and tissue characteristics in patients with a large vessel occlusion treated with endovascular thrombectomy.

INTRODUCTION: To improve our understanding of the relatively poor outcome after endovascular treatment (EVT) in women we assessed possible sex differences in baseline neuroimaging characteristics of acute ischemic stroke patients with large anterior vessel occlusion (LVO). PATIENTS AND METHODS: We included all consecutive patients from the MR CLEAN Registry who underwent EVT between 2014 and 2017. On baseline non-contrast CT and CT angiography, we assessed clot location and clot burden score (CBS), vessel characteristics (presence of atherosclerosis, tortuosity, size, and collateral status), and tissue characteristics with the Alberta Stroke Program Early Computed Tomography Score (ASPECTS). Radiological outcome was assessed with the extended thrombolysis in cerebral infarction score (eTICI) and functional outcome with the modified Rankin Scale score (mRS) at 90 days. Sex-differences were assessed with multivariable regression analyses with adjustments for possible confounders. RESULTS: 3180 patients were included (median age 72 years, 48% women). Clots in women were less often located in the intracranial internal carotid artery (ICA) (25%vs 28%, odds ratio (OR) 0.85;95% confidence interval: 0.73-1.00). CBS was similar between sexes (median 6, IQR 4-8). Intracranial (aOR 0.73;95% CI:0.62-0.87) and extracranial (aOR 0.64;95% CI:0.43-0.95) atherosclerosis was less prevalent in women. Vessel tortuosity was more frequent in women in the cervical ICA (aOR 1.89;95% CI:1.39-2.57) and women more often had severe elongation of the aortic arch (aOR 1.38;95% CI:1.00-1.91). ICA radius was smaller in women (2.3vs 2.5 mm, mean difference 0.22;95% CI:0.09-0.35) while M1 radius was essentially equal (1.6vs 1.7 mm, mean difference 0.09;95% CI:-0.02-0.21). Women had better collateral status (⩾50% filling in 62%vs 53% in men, aOR 1.48;95% CI:1.29-1.70). Finally, ASPECT scores were equal between women and men (median 9 in both sexes, IQR 8-10vs 9-10). Reperfusion rates were similar between women and men (acOR 0.94;95% CI:0.83-1.07). However, women less often reached functional independence than men (34%vs 46%, aOR 0.68;95% CI:0.53-0.86). DISCUSSION AND CONCLUSION: On baseline imaging of this Dutch Registry, men and women with LVO mainly differ in vessel characteristics such as atherosclerotic burden, extracranial vessel tortuosity, and collateral status. These sex differences do not result in different reperfusion rates and are, therefore, not likely to explain the worse functional outcome in women after EVT.

Intravenous Thrombolysis Before Endovascular Treatment in Posterior Circulation Occlusions: A MR CLEAN Registry Study.

BACKGROUND: The effectiveness of intravenous thrombolysis (IVT) before endovascular treatment (EVT) has been investigated in randomized trials and meta-analyses. These studies mainly concerned anterior circulation occlusions. We aimed to investigate clinical, technical, and safety outcomes of IVT before EVT in posterior circulation occlusions in a nationwide registry. METHODS: Patients were included from the MR CLEAN Registry (Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands), a nationwide, prospective, multicenter registry of patients with acute ischemic stroke due to a large intracranial vessel occlusion receiving EVT between 2014 and 2019. All patients with a posterior circulation occlusion were included. Primary outcome was a shift toward better functional outcome on the modified Rankin Scale at 90 days. Secondary outcomes were favorable functional outcome (modified Rankin Scale scores, 0-3), occurrence of symptomatic intracranial hemorrhages, successful reperfusion (extended Thrombolysis in Cerebral Ischemia ≥2B), first-attempt successful reperfusion, and mortality at 90 days. Regression analyses with adjustments based on univariable analyses and literature were applied. RESULTS: A total of 248 patients were included, who received either IVT (n=125) or no IVT (n=123) before EVT. Results show no differences in a shift on the modified Rankin Scale (adjusted common odds ratio, 1.04 [95% CI, 0.61-1.76]). Although symptomatic intracranial hemorrhages occurred more often in the IVT group (4.8% versus 2.4%), regression analysis did not show a significant difference (adjusted odds ratio, 1.65 [95% CI, 0.33-8.35]). Successful reperfusion, favorable functional outcome, first-attempt successful reperfusion, and mortality did not differ between patients treated with and without IVT. CONCLUSIONS: We found no significant differences in clinical, technical, and safety outcomes between patients with a large vessel occlusion in the posterior circulation treated with or without IVT before EVT. Our results are in line with the literature on the anterior circulation.

Sex differences in outcomes after endovascular treatment in posterior circulation stroke: results from the MR CLEAN Registry.

BACKGROUND: Women with anterior circulation large vessel occlusion (LVO) have been reported to have worse outcomes after endovascular treatment (EVT) than men. Whether these disparities also exist in LVO of the posterior circulation is yet uncertain. We assessed sex differences in clinical, technical, and safety outcomes of EVT in posterior circulation LVO. METHODS: We used data of patients with posterior circulation LVO included in the Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands (MR CLEAN) Registry (2014-2018). Primary outcome was the modified Rankin Scale (mRS) score at 90 days assessed with multivariable ordinal regression analysis. Secondary outcomes included favorable functional outcome (mRS ≤3), functional independence (mRS ≤2), death within 90 days, National Institutes of Health Stroke Scale (NIHSS) score 24-48 hours postintervention, complications, successful reperfusion (extended Thrombolysis in Cerebral Ischemia 2B-3), and procedure duration analyzed with multivariable logistic and linear regression analyses. RESULTS: We included 264 patients (42% women). Compared with men, women were older (median age 68 vs 63 years), more often had prestroke disability (mRS ≥1: 37% vs 30%), and received intravenous thrombolytics less often (45% vs 56%). Clinical outcomes were similar between sexes (adjusted (common) OR (aOR) 0.82, 95% CI 0.51 to 1.34; favorable functional outcome 50% vs 43%, aOR 1.31, 95% CI 0.77 to 2.25; death 32% vs 29%, aOR 0.98, 95% CI 0.52 to 1.84). In addition, NIHSS score after 24-48 hours (median 7 vs 9), successful reperfusion (77% vs 73%), and complications did not differ between men and women. CONCLUSIONS: Outcomes in women treated with EVT for posterior circulation LVO were similar compared with men despite less favorable baseline characteristics in women. Therefore men and women may benefit equally from EVT.

Development and validation of a prediction model for failure of the transfemoral approach of endovascular treatment for large vessel occlusion acute ischemic stroke.

INTRODUCTION: Extracranial vascular characteristics determine the accessibility of the large vessel intracranial occlusion for endovascular treatment (EVT) in acute ischemic stroke. We developed and validated a prediction model for failure of the transfemoral approach to aid clinical decision making regarding EVT. METHODS: A prediction model was developed from data of patients included in the Dutch multicenter MR CLEAN Registry (March 18th 2014 until June 15th 2016) with penalized logistic regression. Predictor variables were available prior to the EVT procedure and included age, hypertension and extracranial vascular characteristics assessed on baseline CTA. The prediction model was internally validated, temporally validated within a second MR CLEAN Registry cohort (June 15th 2016 until November 1st 2017) and updated by re-estimating the coefficients using the combined cohort. RESULTS: Failure of the transfemoral approach occurred in 7% of patients, in both cohorts (derivation cohort: n=887, median age 71 years, interquartile range [IQR] 60-80, 52% men; validation cohort: n=1111, median age 73 years, IQR 62-81, 51% men). The prediction model had a c-statistic of 0.81 (95%CI: 0.76-0.86) in the derivation cohort, 0.69 (95%CI: 0.62-0.75) at temporal validation, and 0.75 (95%CI: 0.71-0.79) in the final prediction model, with the following penalized ß-coefficients for predictors age (per decade): 0.26, hypertension: -0.16, severe aortic arch elongation: 1.45, bovine aortic arch: 0.44, elongation of the supra-aortic arteries: 0.72, cervical ICA elongation: 0.44, and high-grade stenosis of the cervical ICA: 0.78. CONCLUSION: Our prediction model showed good performance for prediction of failure to reach the intracranial occlusion by the transfemoral approach.

Early Intubation in Endovascular Therapy for Basilar Artery Occlusion: A Post Hoc Analysis of the BASICS Trial.

BACKGROUND: The optimal anesthetic management for endovascular therapy (EVT) in patients with posterior circulation stroke remains unclear. Our objective was to investigate the impact of early intubation in patients enrolled in the BASICS trial (Basilar Artery International Cooperation Study). METHODS: BASICS was a multicenter, randomized, controlled trial that compared the efficacy of EVT compared with the best medical care alone in patients with basilar artery occlusion. In this post hoc analysis, early intubation within the first 24 hours of the estimated time of basilar artery occlusion was examined as an additional covariate using regression modeling. We estimated the adjusted relative risks (RRs) for favorable outcomes, defined as modified Rankin Scale scores of 0 to 3 at 90 days. An adjusted common odds ratio was estimated for a shift in the distribution of modified Rankin Scale scores at 90 days. RESULTS: Of 300 patients in BASICS, 289 patients were eligible for analysis (151 in the EVT group and 138 in the best medical care group). compared with medical care alone, EVT was related to a higher risk of early intubation (RR, 1.29 [95% CI, 1.09-1.53]; P<0.01), and early intubation was negatively associated with favorable outcome (RR, 0.61 [95% CI, 0.45-0.84]; P=0.002). Whereas there was no overall treatment effect of EVT on favorable outcome (RR, 1.22 [95% CI, 0.95-1.55]; P=0.121), EVT was associated with favorable outcome (RR, 1.34 [95% CI, 1.05-1.71]; P=0.018) and a shift toward lower modified Rankin Scale scores (adjusted common odds ratio, 1.63 [95% CI, 1.04-2.57]; P=0.033) if adjusted for early intubation. CONCLUSIONS: In this post hoc analysis of the neutral BASICS trial, early intubation was linked to unfavorable outcomes, which might mitigate a potential benefit from EVT by indirect effects due to an increased risk of early intubation. This relationship may be considered when assessing the efficacy of EVT in patients with basilar artery occlusion in future trials.

What Is the Evidence for Endovascular Thrombectomy in Posterior Circulation Stroke?

Posterior circulation infarcts comprise approximately 25% of ischemic strokes but are less often treated with recanalization therapy and have longer treatment delays compared with anterior circulation strokes. Among posterior circulation strokes, basilar artery occlusion is associated with the most severe deficits and the worst prognosis. Endovascular thrombectomy is a standard of care for patients with anterior circulation large vessel occlusion, but not until recently were the first randomized controlled trials on endovascular thrombectomy in basilar artery occlusion published. Two of the trials were neutral, whereas two others showed better functional outcome after thrombectomy up to 24 hours of symptom onset compared with best medical treatment, which in most cases had low rates of intravenous thrombolysis. According to observational data, thrombectomy seems to be safe also in isolated posterior cerebral artery occlusions and might be an option for selected patients, even if its outcome benefit is yet to be demonstrated.

Evolution of endovascular therapy trials for basilar artery occlusion.

Basilar artery occlusion (BAO) is an uncommon event, and leads to poor outcome in an estimated 60 to 80% of patients. Two early randomized trials, BASICS and BEST demonstrated equivocal benefit of endovascular therapy (EVT) compared to medical management. These trials helped in forming the design, sample size and eligibility criteria for the subsequent two trials, ATTENTION and BAOCHE which demonstrated superiority of EVT over medical management. In this commentary, we look at the evolution of how early BAO studies formed the building blocks for successive BAO trials, review lessons learned, and opportunities for future research.

Endovascular treatment versus no endovascular treatment after 6-24 h in patients with ischaemic stroke and collateral flow on CT angiography (MR CLEAN-LATE) in the Netherlands: a multicentre, open-label, blinded-endpoint, randomised, controlled, phase 3 trial.

BACKGROUND: Endovascular treatment for anterior circulation ischaemic stroke is effective and safe within a 6 h window. MR CLEAN-LATE aimed to assess efficacy and safety of endovascular treatment for patients treated in the late window (6-24 h from symptom onset or last seen well) selected on the basis of the presence of collateral flow on CT angiography (CTA). METHODS: MR CLEAN-LATE was a multicentre, open-label, blinded-endpoint, randomised, controlled, phase 3 trial done in 18 stroke intervention centres in the Netherlands. Patients aged 18 years or older with ischaemic stroke, presenting in the late window with an anterior circulation large-vessel occlusion and collateral flow on CTA, and a neurological deficit score of at least 2 on the National Institutes of Health Stroke Scale were included. Patients who were eligible for late-window endovascular treatment were treated according to national guidelines (based on clinical and perfusion imaging criteria derived from the DAWN and DEFUSE-3 trials) and excluded from MR CLEAN-LATE enrolment. Patients were randomly assigned (1:1) to receive endovascular treatment or no endovascular treatment (control), in addition to best medical treatment. Randomisation was web based, with block sizes ranging from eight to 20, and stratified by centre. The primary outcome was the modified Rankin Scale (mRS) score at 90 days after randomisation. Safety outcomes included all-cause mortality at 90 days after randomisation and symptomatic intracranial haemorrhage. All randomly assigned patients who provided deferred consent or died before consent could be obtained comprised the modified intention-to-treat population, in which the primary and safety outcomes were assessed. Analyses were adjusted for predefined confounders. Treatment effect was estimated with ordinal logistic regression and reported as an adjusted common odds ratio (OR) with a 95% CI. This trial was registered with the ISRCTN, ISRCTN19922220. FINDINGS: Between Feb 2, 2018, and Jan 27, 2022, 535 patients were randomly assigned, and 502 (94%) patients provided deferred consent or died before consent was obtained (255 in the endovascular treatment group and 247 in the control group; 261 [52%] females). The median mRS score at 90 days was lower in the endovascular treatment group than in the control group (3 [IQR 2-5] vs 4 [2-6]), and we observed a shift towards better outcomes on the mRS for the endovascular treatment group (adjusted common OR 1·67 [95% CI 1·20-2·32]). All-cause mortality did not differ significantly between groups (62 [24%] of 255 patients vs 74 [30%] of 247 patients; adjusted OR 0·72 [95% CI 0·44-1·18]). Symptomatic intracranial haemorrhage occurred more often in the endovascular treatment group than in the control group (17 [7%] vs four [2%]; adjusted OR 4·59 [95% CI 1·49-14·10]). INTERPRETATION: In this study, endovascular treatment was efficacious and safe for patients with ischaemic stroke caused by an anterior circulation large-vessel occlusion who presented 6-24 h from onset or last seen well, and who were selected on the basis of the presence of collateral flow on CTA. Selection of patients for endovascular treatment in the late window could be primarily based on the presence of collateral flow. FUNDING: Collaboration for New Treatments of Acute Stroke consortium, Dutch Heart Foundation, Stryker, Medtronic, Cerenovus, Top Sector Life Sciences & Health, and the Netherlands Brain Foundation.

Association between type of intervention center and outcomes after endovascular treatment for acute ischemic stroke: Results from the MR CLEAN Registry.

Background: Endovascular treatment (EVT) for acute ischemic stroke (AIS) is performed in intervention centers that provide the full range of neuro(endo)vascular care (level 1) and centers that only perform EVT for AIS (level 2). We compared outcomes between these center types and assessed whether differences in outcomes could be explained by center volume (CV). Patients and methods: We analyzed patients included in the MR CLEAN Registry (2014-2018), a registry of all EVT-treated patients in the Netherlands. Our primary outcome was the shift on the modified Rankin scale (mRS) after 90 days (ordinal regression). Secondary outcomes were the NIHSS 24-48 h post-EVT, door-to-groin time (DTGT), procedure time (linear regression), and recanalization (binary logistic regression). We compared outcomes between level 1 and 2 centers using multilevel regression models, with center as random intercept. We adjusted for relevant baseline factors, and in case of observed differences, we additionally adjusted for CV. Results: Of the 5144 patients 62% were treated in level 1 centers. We observed no significant differences between center types in mRS (adjusted(a)cOR: 0.79, 95% CI: 0.40 to 1.54), NIHSS (aß: 0.31, 95% CI: -0.52 to 1.14), procedure duration (aß: 0.88, 95% CI: -5.21 to 6.97), or DTGT (aß: 4.24, 95% CI: -7.09 to 15.57). The probability for recanalization was higher in level 1 centers compared to level 2 centers (aOR 1.60, 95% CI: 1.10 to 2.33), and this difference probably depended on CV. Conclusions: We found no significant differences, that were independent of CV, in the outcomes of EVT for AIS between level 1 and level 2 intervention centers.

Specialist Perspectives on the Imaging Selection of Large Vessel Occlusion in the Late Window.

BACKGROUND: The proper imaging modality for use in the selection of patients for endovascular thrombectomy (EVT) presenting in the late window remains controversial, despite current guidelines advocating the use of advanced imaging in this population. We sought to understand if clinicians with different specialty training differ in their approach to patient selection for EVT in the late time window. METHODS: We conducted an international survey of stroke and neurointerventional clinicians between January and May 2022 with questions focusing on imaging and treatment decisions of large vessel occlusion (LVO) patients presenting in the late window. Interventional neurologists, interventional neuroradiologists, and endovascular neurosurgeons were defined as interventionists whereas all other specialties were defined as non-interventionists. The non-interventionist group was defined by all other specialties of the respondents: stroke neurologist, neuroradiologist, emergency medicine physician, trainee (fellows and residents) and others. RESULTS: Of 3000 invited to participate, 1506 (1027 non-interventionists, 478 interventionists, 1 declined to specify) physicians completed the study. Interventionist respondents were more likely to proceed directly to EVT (39.5% vs. 19.5%; p < 0.0001) compared to non-interventionist respondents in patients with favorable ASPECTS (Alberta Stroke Program Early CT Score). Despite no difference in access to advanced imaging, interventionists were more likely to prefer CT/CTA alone (34.8% vs. 21.0%) and less likely to prefer CT/CTA/CTP (39.1% vs. 52.4%) for patient selection (p < 0.0001). When faced with uncertainty, non-interventionists were more likely to follow clinical guidelines (45.1% vs. 30.2%) while interventionists were more likely to follow their assessment of evidence (38.7% vs. 27.0%) (p < 0.0001). CONCLUSION: Interventionists were less likely to use advanced imaging techniques in selecting LVO patients presenting in the late window and more likely to base their decisions on their assessment of evidence rather than published guidelines. These results reflect gaps between interventionists and non-interventionists reliance on clinical guidelines, the limits of available evidence, and clinician belief in the utility of advanced imaging.

Endovascular Therapy for Basilar Artery Occlusion.

Basilar artery occlusion is one of the most devastating neurological conditions with high risks of disability and mortality. Despite the overwhelming benefit of endovascular therapy (EVT) in the anterior circulation and observational data supporting the efficacy of EVT in the posterior circulation, evidence from randomized controlled trials in basilar artery occlusion had been lacking until recently. The BEST (Basilar Artery Occlusion Endovascular Intervention Versus Standard Medical Treatment) and BASICS (Basilar Artery International Cooperation Study) randomized trials showed a nonsignificant direction of benefit but failed to demonstrate the superiority of EVT over standard medical therapy in basilar artery occlusion. However, these trials paved the way for 2 subsequent positive trials by highlighting the importance of consecutive recruitment, fast enrollment and avoidance or minimization of cross-over. The recently completed ATTENTION (Endovascular Treatment for Acute Basilar Artery Occlusion) and BAOCHE (Basilar Artery Occlusion Chinese Endovascular Trial) trials showed that EVT is beneficial for basilar artery occlusion within 24 hours of onset, with a treatment effect similar to what has been shown in anterior circulation large vessel occlusion ischemic stroke. In this topical review, we examine and contextualize the current evidence on EVT for basilar artery occlusion.

Endovascular versus Medical Management of Acute Basilar Artery Occlusion: A Systematic Review and Meta-Analysis of the Randomized Controlled Trials.

BACKGROUND AND PURPOSE: The optimal management of patients with acute basilar artery occlusion (BAO) is uncertain. We aimed to evaluate the safety and efficacy of endovascular thrombectomy (EVT) compared to medical management (MM) for acute BAO through a meta-analysis of randomized controlled trials (RCTs). METHODS: We performed a systematic review and meta-analysis of RCTs of patients with acute BAO. We analyzed the pooled effect of EVT compared to MM on the primary outcome (modified Rankin Scale [mRS] of 0-3 at 3 months), secondary outcome (mRS 0-2 at 3 months), symptomatic intracranial hemorrhage (sICH), and 3-month mortality rates. For each study, effect sizes were computed as odds ratios (ORs) with random effects and Mantel-Haenszel weighting. RESULTS: Four RCTs met inclusion criteria including 988 patients. There were higher odds of mRS of 0-3 at 90 days in the EVT versus MM group (45.1% vs. 29.1%, OR 1.99, 95% confidence interval [CI] 1.04-3.80; P=0.04). Patients receiving EVT had a higher sICH compared to MM (5.4% vs. 0.8%, OR 7.89, 95% CI 4.10-15.19; P<0.01). Mortality was lower in the EVT group (35.5% vs. 45.1%, OR 0.64, 95% CI 0.42-0.99; P=0.05). In an analysis of two trials with BAO patients and National Institutes of Health Stroke Scale (NIHSS) <10, there was no difference in 90-day outcomes between EVT versus MM. CONCLUSION: In this systematic review and meta-analysis, EVT was associated with favorable outcome and decreased mortality in patients with BAO up to 24 hours from stroke symptoms compared to MM. The treatment effect in BAO patients with NIHSS <10 was less certain. Further studies are of interest to evaluate the efficacy of EVT in basilar occlusion patients with milder symptoms.

Basilar artery occlusion management: Specialist perspectives from an international survey.

BACKGROUND AND PURPOSE: Two early basilar artery occlusion (BAO) randomized controlled trials did not establish the superiority of endovascular thrombectomy (EVT) over medical management. While many providers continue to recommend EVT for acute BAO, perceptions of equipoise in randomizing patients with BAO to EVT versus medical management may differ between clinician specialties. METHODS: We conducted an international survey (January 18, 2022 to March 31, 2022) regarding management strategies in acute BAO prior to the announcement of two trials indicating the superiority of EVT, and compared responses between interventionalists (INTs) and non-interventionalists (nINTs). Selection practices for routine EVT and perceptions of equipoise regarding randomizing to medical management based on neuroimaging and clinical features were compared between the two groups using descriptive statistics. RESULTS: Among the 1245 respondents (nINTs = 702), INTs more commonly believed that EVT was superior to medical management in acute BAO (98.5% vs. 95.1%, p < .01). A similar proportion of INTs and nINTs responded that they would not randomize a patient with BAO to EVT (29.4% vs. 26.7%), or that they would only under specific clinical circumstances (p = .45). Among respondents who would recommend EVT for BAO, there was no difference in the maximum prestroke disability, minimum stroke severity, or infarct burden on computed tomography between the two groups (p > .05), although nINTs more commonly preferred perfusion imaging (24.2% vs. 19.7%, p = .04). Among respondents who indicated they would randomize to medical management, INTs were more likely to randomize when the National Institutes of Health Stroke Scale was ≥10 (15.9% vs. 6.9%, p < .01). CONCLUSIONS: Following the publication of two neutral clinical trials in BAO EVT, most stroke providers believed EVT to be superior to medical management in carefully selected patients, with most indicating they would not randomize a BAO patient to medical treatment. There were small differences in preference for advanced neuroimaging for patient selection, although these preferences were unsupported by clinical trial data at the time of the survey.

Endovascular thrombectomy for basilar artery occlusion: translating research findings into clinical practice.

BACKGROUND: Basilar artery occlusion is a rare and severe condition. The effectiveness of endovascular thrombectomy in patients with basilar artery occlusion was unclear until recently, because these patients were excluded from most trials of endovascular thrombectomy for large-vessel occlusion ischaemic stroke. RECENT DEVELOPMENTS: The Basilar Artery International Cooperation Study (BASICS) and the Basilar Artery Occlusion Endovascular Intervention versus Standard Medical Treatment (BEST) trials, specifically designed to investigate the benefit of thrombectomy in patients with basilar artery occlusion, did not find significant evidence of a benefit of endovascular thrombectomy in terms of disability outcomes at 3 months after stroke. However, these trials suggested a potential benefit of endovascular thrombectomy in patients presenting with moderate-to-severe symptoms. Subsequently, the Endovascular Treatment for Acute Basilar Artery Occlusion (ATTENTION) and the Basilar Artery Occlusion Chinese Endovascular (BAOCHE) trials, which compared endovascular thrombectomy versus medical therapy within 24 h of onset, showed clear benefit of endovascular thrombectomy in reducing disability and mortality, particularly in patients with moderate-to-severe symptoms. The risk of intracranial haemorrhage with endovascular thrombectomy was similar to the risk in anterior circulation stroke. Thrombectomy was beneficial regardless of age, baseline characteristics, the presence of intracranial atherosclerotic disease, and time from symptom onset to randomisation. Therefore, the question of whether endovascular thrombectomy is beneficial in basilar artery occlusion now appears to be settled in patients with moderate-to-severe symptoms, and endovascular thrombectomy should be offered to eligible patients. WHERE NEXT?: Key outstanding issues are the potential benefits of endovascular thrombectomy in patients with mild symptoms, the use of intravenous thrombolysis in an extended time window (ie, after 4·5 h of symptom onset), and the optimal endovascular technique for thrombectomy. Dedicated training programmes and automated software to assist with the assessment of imaging prognostic markers could be useful in the selection of patients who might benefit from endovascular thrombectomy. Large international research networks should be built to address knowledge gaps in this field and allow the conduct of clinical trials with fast and consecutive enrolment and a diverse ethnic representation.

Clinical Predictors for Early Mortality of Patients with Acute Basilar Artery Occlusion.

BACKGROUND: Acute ischemic stroke due to basilar artery occlusion (BAO) is associated with the highest mortality in patients with large vessel occlusion. This study aimed to identify modifiable risk factors of early mortality in patients with BAO. METHODS AND RESULTS: This was a cohort study of consecutive patients with BAO admitted to 47 stroke centers in China between January 2014 and May 2019. The primary outcome was all-cause mortality within 7 days after hospitalization. Of 829 patients, 164 died (0-3 days: 115; 4-7 days: 49) within 7 days after hospitalization. Among pre- and periprocedural variables, higher admission National Institutes of Health Stroke Scale (NIHSS, adjusted OR, 1.06, 95% CI: 1.04-1.09; p < 0.001), lower admission posterior circulation-Alberta Stroke Program Early Computed Tomography Score (pc-ASPECTS, adjusted OR, 0.88, 95% CI: 0.79-0.98; p = 0.02), lower Basilar Artery on Computed Tomography Angiography score (BATMAN, adjusted OR, 0.84, 95% CI: 0.76-0.93; p = 0.001), and recanalization failure (adjusted OR, 2.99, 95% CI: 2.04-4.38; p < 0.001) were independently associated with a higher risk of early mortality. Herniation (adjusted OR, 2.84, 95% CI: 1.52-5.30; p = 0.001) is an independent postprocedural predictor of early mortality. In patients dying ≤3 days, higher NIHSS (p < 0.001), lower pc-ASPECTS (p = 0.01), lower BATMAN (p = 0.004), recanalization failure (p < 0.001), herniation (p = 0.001), gastrointestinal hemorrhage (p = 0.046), and absence of pneumonia (p < 0.001) were independent predictors of early mortality. Higher NIHSS (p = 0.01), recanalization failure (p < 0.001), and pneumonia (p = 0.03) were independently associated with early mortality between 4 and 7 days. CONCLUSIONS: Recanalization failure, herniation, gastrointestinal hemorrhage, and pneumonia are potentially modifiable risk factors for early mortality in basilar artery occlusion.