Prevalence and Distribution of Intracranial Vessel Occlusion on Angiography and Its Association with Functional Outcome in Patients with Atrial Fibrillation Presenting with Ischemic Stroke.

OBJECTIVES: To determine the prevalence and distribution of intracranial vessel occlusion identified on computed tomography (CT) or magnet resonance (MR) angiography and to explore its association with functional outcome in patients with atrial fibrillation (AF) and ischemic stroke. METHODS: Multicenter cohort study enrolling consecutive patients with AF with imaging-confirmed ischemic stroke who underwent CT- or MR-angiography on admission (2014-2022). Multivariable regression was used to explore the association between intracranial vessel occlusion and poor functional outcome (modified Rankin Scale score 3-6) at 90 days. RESULTS: The analysis included 10,164 patients (median age 81.5 years, 47.8% female, median National Institutes of Health Stroke Scale score on admission 6; 14.7% on a vitamin K antagonist [VKA], 27.5% on a direct oral anticoagulant [DOAC], 57.8% not receiving oral anticoagulation). Angiography showed intracranial vessel occlusion in 5,190 patients (51.1%), affecting the anterior cerebral circulation in 87.4%. Overall, 29.2% and 29.4% of patients received thrombolysis and mechanical thrombectomy, respectively. The proportion of patients with poor functional outcome at 90 days was 60.6% and 42.7% in those with and without vessel occlusion, respectively. In multivariable analyses, vessel occlusion was associated with poor functional outcome (adjusted odds ratio [aOR]: 1.95, 95% confidence interval [CI]: 1.71-2.22) with consistent results in subgroups according to oral anticoagulation use (VKA, aOR: 1.98, 95% CI: 1.40-2.80; DOAC, aOR: 2.35, 95% CI: 1.83-3.03; none, aOR: 1.76, 95% CI: 1.49-2.09). INTERPRETATION: Intracranial vessel occlusion is common in patients with AF with ischemic stroke, mainly affects the anterior circulation and is associated with poor functional outcome. ANN NEUROL 2024.

Toward Individual Treatment in Cervical Artery Dissection: Subgroup Analysis of the TREAT-CAD Randomized Trial.

OBJECTIVE: Uncertainty remains regarding antithrombotic treatment in cervical artery dissection. This analysis aimed to explore whether certain patient profiles influence the effects of different types of antithrombotic treatment. METHODS: This was a post hoc exploratory analysis based on the per-protocol dataset from TREAT-CAD (NCT02046460), a randomized controlled trial comparing aspirin to anticoagulation in patients with cervical artery dissection. We explored the potential effects of distinct patient profiles on outcomes in participants treated with either aspirin or anticoagulation. Profiles included (1) presenting with ischemia (no/yes), (2) occlusion of the dissected artery (no/yes), (3) early versus delayed treatment start (median), and (4) intracranial extension of the dissection (no/yes). Outcomes included clinical (stroke, major hemorrhage, death) and magnetic resonance imaging outcomes (new ischemic or hemorrhagic brain lesions) and were assessed for each subgroup in separate logistic models without adjustment for multiple testing. RESULTS: All 173 (100%) per-protocol participants were eligible for the analyses. Participants without occlusion had decreased odds of events when treated with anticoagulation (odds ratio [OR] = 0.28, 95% confidence interval [CI] = 0.07-0.86). This effect was more pronounced in participants presenting with cerebral ischemia (n = 118; OR = 0.16, 95% CI = 0.04-0.55). In the latter, those with early treatment (OR = 0.26, 95% CI = 0.07-0.85) or without intracranial extension of the dissection (OR = 0.34, 95% CI = 0.11-0.97) had decreased odds of events when treated with anticoagulation. INTERPRETATION: Anticoagulation might be preferable in patients with cervical artery dissection presenting with ischemia and no occlusion or no intracranial extension of the dissection. These findings need confirmation. ANN NEUROL 2024;95:886-897.

Effect of Asymptomatic and Symptomatic COVID-19 on Acute Ischemic Stroke Revascularization Outcomes.

BACKGROUND: The association of COVID-19 with higher bleeding risk and worse outcomes in acute ischemic stroke (AIS) undergoing revascularization may be related to the presence of infection symptoms. We aimed to assess the safety and outcomes of revascularization treatments in patients with AIS with asymptomatic COVID-19 (AS-COVID) or symptomatic COVID-19 (S-COVID). METHODS: We conducted an international multicenter retrospective cohort study of consecutive AIS tested for SARS-CoV-2, receiving intravenous thrombolysis and endovascular treatment between 2020 and 2021. We compared COVID-negative controls, AS-COVID, and S-COVID using multivariable regression. We assessed symptomatic intracranial hemorrhage (symptomatic intracerebral hemorrhage), mortality, and 3-month disability (modified Rankin Scale score). RESULTS: Among 15 124 patients from 105 centers (median age, 71 years; 49% men; 39% treated with intravenous thrombolysis only; and 61% with endovascular treatment±intravenous thrombolysis), 849 (5.6%) had COVID-19, of whom 395 (46%) were asymptomatic and 454 (54%) symptomatic. Compared with controls, both patients with AS-COVID and S-COVID had higher symptomatic intracerebral hemorrhage rates (COVID-controls, 5%; AS-COVID, 7.6%; S-COVID, 9.4%; adjusted odds ratio [aOR], 1.43 [95% CI, 1.03-1.99]; aOR, 1.63 [95% CI, 1.14-2.32], respectively). Only in patients with symptomatic infections, we observed a significant increase in mortality at 24 hours (COVID-controls, 1.3%; S-COVID, 4.8%; aOR, 2.97 [95% CI, 1.76-5.03]) and 3 months (COVID-controls, 19.5%; S-COVID, 40%; aOR, 2.64 [95% CI, 2.06-3.37]). Patients with COVID-19 had worse 3-month disability regardless of disease symptoms although disability was affected to a greater extent in symptomatic patients (aOR for worse modified Rankin Scale score shift: AS-COVID, 1.25 [95% CI, 1.03-1.51]; S-COVID, 2.10 [95% CI, 1.75-2.53]). S-COVID had lower successful recanalization (74.9% versus 85.6%; P<0.001), first pass recanalization (20.3% versus 28.3%; P=0.005), and a higher number of passes. CONCLUSIONS: In AIS undergoing revascularization treatments, both AS-COVID and S-COVID influence the risk of intracranial bleeding and worse clinical outcomes. The magnitude of this effect is more pronounced in symptomatic infections, which also present less favorable recanalization outcomes. These findings emphasize the impact of SARS-CoV-2 infection on the prognosis of revascularized AIS independent of symptom status. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04895462.

Moving From CT to MRI Paradigm in Acute Ischemic Stroke: Feasibility, Effects on Stroke Diagnosis and Long-Term Outcomes.

BACKGROUND: The relative value of computed tomography (CT) and magnetic resonance imaging (MRI) in acute ischemic stroke (AIS) is debated. In May 2018, our center transitioned from using CT to MRI as first-line imaging for AIS. This retrospective study aims to assess the effects of this paradigm change on diagnosis and disability outcomes. METHODS: We compared all consecutive patients with confirmed diagnosis of AIS admitted to our center during the MRI-period (May 2018-August 2022) and an identical number of patients from the preceding CT-period (December 2012-April 2018). Univariable and multivariable analyses were performed to evaluate outcomes, including the number and delay of imaging exams, the rate of missed strokes, stroke mimics treated with thrombolysis, undetermined stroke mechanisms, length of hospitalization, and 3-month disability. RESULTS: The median age of the 2972 included patients was 76 years (interquartile range, 65-84), and 46% were female. In the MRI-period, 80% underwent MRI as first acute imaging. The proportion of patients requiring a second acute imaging modality for diagnostic ± revascularization reasons increased from 2.1% to 5% (Punadj <0.05), but it decreased in the subacute phase from 79.0% to 60.1% (Padj <0.05). In thrombolysis candidates, there was a 2-minute increase in door-to-imaging delay (Padj <0.05). The rates of initially missed AIS diagnosis was similar (3.8% versus 4.4%, Padj=0.32) and thrombolysis in stroke mimics decreased by half (8.6% versus 4.3%; Padj <0.05). Rates of unidentified stroke mechanism at hospital discharge were similar (22.8% versus 28.1%; Padj=0.99). The length of hospitalization decreased from 9 (interquartile range, 6-14) to 7 (interquartile range, 4-12) days (Padj=0.62). Disability at 3 months was similar (common adjusted odds ratio for favorable Rankin shift, 0.98 [95% CI, 0.71-1.36]; Padj=0.91), as well as mortality and symptomatic intracranial hemorrhage. CONCLUSIONS: A paradigm shift from CT to MRI as first-line imaging for AIS seems feasible in a comprehensive stroke center, with a minimally increased delay to imaging in thrombolysis candidates. MRI was associated with reduced thrombolysis rates of stroke mimics and subacute neuroimaging needs.

Endovascular Versus Medical Therapy in Posterior Cerebral Artery Stroke: Role of Baseline NIHSS Score and Occlusion Site.

BACKGROUND: Acute ischemic stroke with isolated posterior cerebral artery occlusion (iPCAO) lacks management evidence from randomized trials. We aimed to evaluate whether the association between endovascular treatment (EVT) and outcomes in iPCAO acute ischemic stroke is modified by initial stroke severity (baseline National Institutes of Health Stroke Scale [NIHSS]) and arterial occlusion site. METHODS: Based on the multicenter, retrospective, case-control study of consecutive iPCAO acute ischemic stroke patients (PLATO study [Posterior Cerebral Artery Occlusion Stroke]), we assessed the heterogeneity of EVT outcomes compared with medical management (MM) for iPCAO, according to baseline NIHSS score (≤6 versus >6) and occlusion site (P1 versus P2), using multivariable regression modeling with interaction terms. The primary outcome was the favorable shift of 3-month modified Rankin Scale (mRS). Secondary outcomes included excellent outcome (mRS score 0-1), functional independence (mRS score 0-2), symptomatic intracranial hemorrhage, and mortality. RESULTS: From 1344 patients assessed for eligibility, 1059 were included (median age, 74 years; 43.7% women; 41.3% had intravenous thrombolysis): 364 receiving EVT and 695 receiving MM. Baseline stroke severity did not modify the association of EVT with 3-month mRS distribution (Pinteraction=0.312) but did with functional independence (Pinteraction=0.010), with a similar trend on excellent outcome (Pinteraction=0.069). EVT was associated with more favorable outcomes than MM in patients with baseline NIHSS score >6 (mRS score 0-1, 30.6% versus 17.7%; adjusted odds ratio [aOR], 2.01 [95% CI, 1.22-3.31]; mRS score 0 to 2, 46.1% versus 31.9%; aOR, 1.64 [95% CI, 1.08-2.51]) but not in those with NIHSS score ≤6 (mRS score 0-1, 43.8% versus 46.3%; aOR, 0.90 [95% CI, 0.49-1.64]; mRS score 0-2, 65.3% versus 74.3%; aOR, 0.55 [95% CI, 0.30-1.0]). EVT was associated with more symptomatic intracranial hemorrhage regardless of baseline NIHSS score (Pinteraction=0.467), while the mortality increase was more pronounced in patients with NIHSS score ≤6 (Pinteraction=0.044; NIHSS score ≤6: aOR, 7.95 [95% CI, 3.11-20.28]; NIHSS score >6: aOR, 1.98 [95% CI, 1.08-3.65]). Arterial occlusion site did not modify the association of EVT with outcomes compared with MM. CONCLUSIONS: Baseline clinical stroke severity, rather than the occlusion site, may be an important modifier of the association between EVT and outcomes in iPCAO. Only severely affected patients with iPCAO (NIHSS score >6) had more favorable disability outcomes with EVT than MM, despite increased mortality and symptomatic intracranial hemorrhage.

Sex Differences in Outcomes of Late-Window Endovascular Stroke Therapy.

BACKGROUND: The association between sex and outcome after endovascular thrombectomy of acute ischemic stroke is unclear. The aim of this study was to compare the clinical and safety outcomes between men and women treated with endovascular thrombectomy in the late 6-to-24-hour window period. METHODS: This multicenter, retrospective observational cohort study included consecutive patients who underwent endovascular thrombectomy of anterior circulation stroke in the late window from 66 clinical sites in 10 countries from January 2014 to May 2022. The primary outcome was the 90-day ordinal modified Rankin Scale score. Secondary outcomes included 90-day functional independence (FI), return of Rankin (RoR) to prestroke baseline, FI or RoR, symptomatic intracranial hemorrhage, and mortality. Multivariable and inverse probability of treatment weighting methods were used. We explored the interaction of sex with baseline characteristics on the outcomes ordinal modified Rankin Scale and FI or RoR. RESULTS: Of 1932 patients, 1055 were women and 877 were men. Women were older (77 versus 69 years), had higher rates of atrial fibrillation, hypertension, and greater prestroke disability, but there was no difference in baseline National Institutes of Health Stroke Scale score. Inverse probability of treatment weighting analysis showed no difference between women and men in ordinal modified Rankin Scale (odds ratio, 0.98 [95% CI, 0.79-1.21]), FI or RoR (odds ratio, 0.98 [95% CI, 0.78-1.22]), severe disability or mortality (odds ratio, 0.99 [95% CI, 0.80-1.23]). The multivariable analysis of the above end points was concordant. There were no interactions between baseline characteristics and sex on the outcomes of ordinal modified Rankin Scale and FI or RoR. CONCLUSIONS: In late presenting patients with anterior circulation stroke treated with endovascular thrombectomy in the 6 to 24-hour window, there was no difference in clinical or safety outcomes between men and women.

Revascularization of arterial occlusions in posterior circulation acute ischemic stroke.

PURPOSE OF REVIEW: This review highlights the latest advancements achieved in the revascularization of arterial occlusions associated with an acute ischemic stroke affecting the posterior circulation. It delves into the frequency and outcomes based on specific arterial segments and presents current evidence supporting revascularization treatments, including intravenous thrombolysis and endovascular thrombectomy. RECENT FINDINGS: Comprehensive evidence for treatment across major arterial segments of the posterior circulation -- vertebral artery, basilar artery, posterior cerebral artery, cerebellar arteries, and multilevel posterior occlusions -- is provided. Additionally, the latest findings from randomized clinical trials on basilar artery occlusion are explored alongside results from extensive retrospective analyses of isolated vertebral and posterior cerebral artery occlusions. SUMMARY: Current research supports the treatment decision in acute ischemic strokes of the posterior circulation using both intravenous thrombolysis and endovascular thrombectomy. This review also emphasizes existing knowledge gaps in the management of these strokes and advocates for more randomized clinical trials, notably concerning the posterior cerebral artery (currently ongoing), isolated vertebral artery, and multilevel posterior circulation occlusions.

Intravenous Thrombolysis 4.5-9 Hours After Stroke Onset: A Cohort Study from the TRISP Collaboration.

OBJECTIVE: To investigate the safety and effectiveness of intravenous thrombolysis (IVT) >4.5-9 hours after stroke onset, and the relevance of advanced neuroimaging for patient selection. METHODS: Prospective multicenter cohort study from the ThRombolysis in Ischemic Stroke Patients (TRISP) collaboration. Outcomes were symptomatic intracranial hemorrhage, poor 3-month functional outcome (modified Rankin scale 3-6) and mortality. We compared: (i) IVT >4.5-9 hours versus 0-4.5 hours after stroke onset and (ii) within the >4.5-9 hours group baseline advanced neuroimaging (computed tomography perfusion, magnetic resonance perfusion or magnetic resonance diffusion-weighted imaging fluid-attenuated inversion recovery) versus non-advanced neuroimaging. RESULTS: Of 15,827 patients, 663 (4.2%) received IVT >4.5-9 hours and 15,164 (95.8%) within 4.5 hours after stroke onset. The main baseline characteristics were evenly distributed between both groups. Time of stroke onset was known in 74.9% of patients treated between >4.5 and 9 hours. Using propensity score weighted binary logistic regression analysis (onset-to-treatment time >4.5-9 hours vs onset-to-treatment time 0-4.5 hours), the probability of symptomatic intracranial hemorrhage (ORadjusted 0.80, 95% CI 0.53-1.17), poor functional outcome (ORadjusted 1.01, 95% CI 0.83-1.22), and mortality (ORadjusted 0.80, 95% CI 0.61-1.04) did not differ significantly between both groups. In patients treated between >4.5 and 9 hours, the use of advanced neuroimaging was associated with a 50% lower mortality compared with non-advanced imaging only (9.9% vs 19.7%; ORadjusted 0.51, 95% CI 0.33-0.79). INTERPRETATION: This study showed no evidence in difference of symptomatic intracranial hemorrhage, poor outcome, and mortality in selected stroke patients treated with IVT between >4.5 and 9 hours after stroke onset compared with those treated within 4.5 hours. Advanced neuroimaging for patient selection was associated with lower mortality. ANN NEUROL 2023;94:309-320.

Prevalence and Factors Associated with Carotid Stenosis in Acute Ischemic Stroke Patients with Atrial Fibrillation.

INTRODUCTION: Among stroke patients with atrial fibrillation (AF), it is not uncommon to identify carotid atherosclerosis. This study aimed to estimate the prevalence of, and factors associated with, carotid atherosclerosis among patients with AF and acute ischemic stroke. PATIENTS AND METHODS: Prospectively collected data from consecutive patients with anterior ischemic stroke and AF who underwent carotid imaging from 10 stroke registries were categorized retrospectively according to the degree of stenosis in: no atherosclerosis, stenosis <50%, stenosis ≥50%, and occlusion. Logistic regression analysis was used to identify factors associated with ipsilateral carotid atherosclerosis. RESULTS: Among 2,955 patients with ischemic stroke and AF, carotid atherosclerosis was evident in 1,022 (34.6%) patients, while carotid stenosis ≥50% and occlusion were identified in 204 (6.9%) and 168 (5.7%) patients, respectively. Ipsilateral carotid stenosis ≥50% or occlusion was associated with higher age (OR: 1.15, 95% CI: 1.01-1.32, per decade), previous ischemic stroke or transient ischemic attack (OR: 1.70, 95% CI: 1.29-2.25), peripheral artery disease (OR: 1.85, 95% CI: 1.23-2.78), coronary artery disease (OR: 1.53, 95% CI: 1.16-2.04), and statin treatment on admission (OR: 1.30, 95% CI: 1.01-1.67). Patients with lacunar stroke had a lower likelihood of stenosis ≥50% or occlusion (OR: 0.29, 95% CI: 0.13-0.68). Compared to the absence of atherosclerotic disease, atherosclerosis in one and two arterial beds was associated with the identification of ipsilateral carotid stenosis (OR: 1.49, 95% CI: 1.22-2.98 and OR: 3.18, 95% CI: 1.85-5.49, respectively). CONCLUSION: Among acute ischemic stroke patients with AF, 1 out of 3 had ipsilateral carotid atherosclerosis, and 1 out of 8 had ipsilateral carotid stenosis ≥50% or occlusion. Atherosclerosis in two arterial beds was the most important predictor for the identification of ipsilateral carotid stenosis. Among ischemic stroke patients with AF, carotid atherosclerosis is common, while carotid imaging should not be overlooked, especially in those with coronary or/and peripheral artery disease.

Service delivery in acute ischemic stroke patients: Does sex matter?

BACKGROUND AND PURPOSE: Women with acute ischemic stroke (AIS) are older and have greater preexisting handicap than men. Given that these factors do not fully explain their poorer long-term outcomes, we sought to investigate potential sex differences in the delivery of acute stroke care in a large cohort of consecutive AIS patients. METHODS: We analyzed all patients from ASTRAL (Acute Stroke Registry and Analysis of Lausanne) from March 2003 to December 2019. Multivariable analyses were performed on acute time metrics, revascularization therapies, ancillary examinations for stroke workup, subacute symptomatic carotid artery revascularization, frequency of change in goals of care (palliative care), and length of hospital stay. RESULTS: Of the 5347 analyzed patients, 45% were biologically female and the median age was 74.6 years. After multiple adjustments, female sex was significantly associated with higher onset-to-door (adjusted hazard ratio [aHR] = 1.09, 95% confidence interval [CI] = 1.04-1.14) and door-to-endovascular-puncture intervals (aHR = 1.15, 95% CI = 1.05-1.25). Women underwent numerically fewer diagnostic examinations (adjusted odds ratio [aOR] = 0.94, 95% CI = 0.85-1.04) and fewer subacute carotid revascularizations (aOR = 0.69, 95% CI = 0.33-1.18), and had longer hospital stays (aHR = 1.03, 95% CI = 0.99-1.07), but these differences were not statistically significant. We found no differences in the rates of acute revascularization treatments, or in the frequency of change of goals of treatments. CONCLUSIONS: This retrospective analysis of a large, consecutive AIS cohort suggests that female sex is associated with unfavorable pre- and in-hospital time metrics, such as a longer onset-to-door and door-to-endovascular-puncture intervals. Such indicators of less effective stroke care delivery may contribute to the poorer long-term functional outcomes in female patients and require further attention.

Undiagnosed major risk factors in acute ischaemic stroke patients: frequency, profile, stroke mechanisms and outcome.

BACKGROUND AND PURPOSE: There is scarce clinical information about the clinical profile of patients with acute ischaemic stroke with previously undiagnosed major vascular risk factors (UMRFs). METHODS: This was a retrospective analysis of data from the Acute Stroke Registry and Analysis of Lausanne registry between 2003 and 2018 with univariate and multivariate logistic regression analyses comparing clinical profiles of patients with UMRFs to patients with at least one previously diagnosed MRF (DMRF). RESULTS: In all, 4354 patients (median age 70 years [interquartile range 15.2], 44.7% female) were included after excluding 763 (14.9%) for lack of consent and three for missing information. Amongst 1125 (25.8%) UMRF patients, 69.7% (n = 784) had at least one newly diagnosed MRF and the others none. The newly detected MRFs were dyslipidaemia (61.4%), hypertension (23.7%), atrial fibrillation (10.2%), diabetes mellitus (5.2%), ejection fraction <35% (2.0%) and coronary disease (1.0%). Comparing UMRF patients to DMRF patients, multivariate analysis showed a positive association with lower age, non-Caucasian ethnicity, contraceptive use (<55 years old), smoking (≥55 years old) and patent-foramen-ovale-related stroke mechanism. A negative association was found with pre-stroke antiplatelet use and higher body mass index. Functional outcome did not differ. Cerebrovascular recurrences were similar between groups. CONCLUSIONS: In this large single-centre cohort, 69.7% of patients with acute ischaemic stroke and UMRF were newly diagnosed with at least one new MRF, the most common being dyslipidaemia, hypertension or atrial fibrillation. Patients of the UMRF group were younger, more often smokers and on contraceptives, and had more patent-foramen-ovale-related strokes.

Acute ischaemic stroke in active cancer versus non-cancer patients: stroke characteristics, mechanisms and clinical outcomes.

BACKGROUND AND PURPOSE: Demographics, clinical characteristics, stroke mechanisms and long-term outcomes were compared between acute ischaemic stroke (AIS) patients with active cancer (AC) versus non-cancer patients. METHODS: Using data from 2003 to 2021 in the Acute STroke Registry and Analysis of Lausanne, a retrospective cohort study was performed comparing patients with AC, including previously known and newly diagnosed cancers, with non-cancer patients. Patients with inactive cancer were excluded. Outcomes were the modified Rankin Scale (mRS) score at 3 months, death and cerebrovascular recurrences at 12 months before and after propensity score matching. RESULTS: Amongst 6686 patients with AIS, 1065 (15.9%) had a history of cancer. After excluding 700 (10.4%) patients with inactive cancer, there were 365 (5.5%) patients with AC and 5621 (84%) non-cancer AIS patients. Amongst AC patients, 154 (42.2%) strokes were classified as cancer related. In multivariable analysis, patients with AC were older (adjusted odds ratio [aOR] 1.02, 95% confidence interval [CI] 1.00-1.03), had fewer vascular risk factors and were 48% less likely to receive reperfusion therapies (aOR 0.52, 95% CI 0.35-0.76). Three-month mRS scores were not different in AC patients (aOR 2.18, 95% CI 0.96-5.00). At 12 months, death (adjusted hazard ratio 1.91, 95% CI 1.50-2.43) and risk of cerebrovascular recurrence (sub-distribution hazard ratio 1.68, 95% CI 1.22-2.31) before and after propensity score matching were higher in AC patients. CONCLUSIONS: In a large institutional registry spanning nearly two decades, AIS patients with AC had less past cerebrovascular disease but a higher 1-year risk of subsequent death and cerebrovascular recurrence compared to non-cancer patients. Antithrombotic medications at discharge may reduce this risk in AC patients.

Sex differences in acute stroke metrics and outcome dependent on COVID status.

BACKGROUND AND PURPOSE: Biological sex is known to have an impact on quality metrics of acute stroke. We aimed to determine whether COVID positivity accentuates this effect and constitutes worse outcome. METHODS: The present analysis was based on the Global COVID-19 Stroke Registry, a retrospective, international, cohort study of consecutive ischemic stroke patients receiving intravenous thrombolysis and/or endovascular thrombectomy between 1 March 2020 and 30 June 2021. We investigated differences between the sexes in patient characteristics, acute stroke metrics as well as post-stroke outcome in COVID-positive and COVID-negative stroke patients undergoing acute revascularization procedures. RESULTS: A total of 15,128 patients from 106 centers were recorded in the Global COVID-19 Stroke Registry, 853 (5.6%) of whom were COVID-positive. Overall, COVID-positive individuals were treated significantly slower according to every acute stroke metric compared to COVID-negative patients. We were able to show that key quality indicators in acute stroke treatment were unfavorable for COVID-negative women compared to men (last-seen-well-to-door time + 11 min in women). Furthermore, COVID-negative women had worse 3-month outcomes (3-month modified Rankin Scale score [interquartile range] 3.0 [4.0] vs. 2.0 [3.0]; p < 0.01), even after adjusting for confounders. In COVID-positive individuals no such difference between the sexes, either in acute management metrics or in 3-month outcome, was seen. CONCLUSION: Known sex-related differences in acute stroke management exist and extend to times of crisis. Nevertheless, if patients were COVID-19-positive at stroke onset, women and men were treated the same, which could be attributed to structured treatment pathways.

Perfusion Imaging Mismatch Profiles in the Early Thrombectomy Window: A Single-Center Analysis.

BACKGROUND: Little is known on the role of mismatch profile in patients undergoing early endovascular treatment (EVT). We aimed to describe pretreatment perfusion parameters and mismatch profiles in anterior circulation large vessel occlusion acute ischemic stroke undergoing EVT in the early time window and assess their association with time from stroke onset and outcomes. METHODS: Retrospective single-center study, including early (<6 hours) EVT-treated large vessel occlusion acute ischemic stroke with baseline perfusion data, assessing perfusion parameters (ischemic core volume, mismatch volume and mismatch ratio) and mismatch profiles (favorable versus unfavorable, based on criteria adopted in EXTEND-IA [Extending the Time for Thrombolysis in Emergency Neurological Deficits - Intra-Arterial], SWIFT PRIME [Solitaire With the Intention for Thrombectomy as Primary Endovascular Treatment], DEFUSE 3 [Endovascular Therapy Following Imaging Evaluation for Ischemic Stroke 3], and DAWN [Clinical Mismatch in the Triage of Wake Up and Late Presenting Strokes Undergoing Neurointervention With Trevo] trials). We evaluated their association with time from stroke onset (rs [for parameters] or χ2 for trend [for profiles]) and association with modified Rankin Scale score >2, symptomatic intracranial hemorrhage, and mortality (multivariate regression analyses [each parameter/profile entered into a separate logistic regression model, adjusted for baseline variables associated with each outcome in the univariate analysis at the P<0.1 level]). RESULTS: Among 357 patients, unfavorable mismatch profiles ranged from 21% to 60%, depending on the criterion, and were not correlated with time from stroke onset (P=0.490). All individual perfusion parameters and unfavorable mismatch profiles were associated with poor functional outcome: ischemic core volume adjusted odds ratio (aOR), 1.49 ([95% CI, 1.13-1.97] P=0.005); penumbral volume aOR, 0.30 ([95% CI, 0.10-0.84] P=0.022); mismatch ratio aOR, 0.67 ([95% CI, 0.50-0.90] P=0.007); EXTEND-IA aOR, 2.61 ([95% CI, 1.23-5.51] P=0.012); SWIFT PRIME aOR, 2.50 ([95% CI, 1.30-4.57] P=0.006); DEFUSE 3 aOR, 2.28 ([95% CI, 1.14-4.57] P=0.020); and DAWN aOR, 4.19 ([95% CI, 2.13-8.26] P<0.001). EXTEND-IA and DEFUSE 3 unfavorable profiles were also independently associated with symptomatic intracranial hemorrhage (aOR, 3.82 [95% CI, 1.42-10.3]; P=0.008 and aOR, 2.83 [95% CI, 1.09-7.36]; P=0.033) and death (aOR, 3.26 [95% CI, 1.33-8.02]; P=0.010 and aOR, 2.52 [95% CI, 1.10-5.82]; P=0.030). CONCLUSIONS: Pretreatment perfusion parameters and mismatch profiles in early EVT-treated patients were not correlated with time from stroke onset but were independently associated with functional outcome. Mismatch assessment in the early time window may improve EVT patient selection, independently of onset-to-treatment time.

Endovascular Therapy or Medical Management Alone for Isolated Posterior Cerebral Artery Occlusion: A Multicenter Study.

BACKGROUND: Whether endovascular therapy (EVT) added on best medical management (BMM), as compared to BMM alone, is beneficial in acute ischemic stroke with isolated posterior cerebral artery occlusion is unknown. METHODS: We conducted a multicenter international observational study of consecutive stroke patients admitted within 6 hours from symptoms onset in 26 stroke centers with isolated occlusion of the first (P1) or second (P2) segment of the posterior cerebral artery and treated either with BMM+EVT or BMM alone. Propensity score with inverse probability of treatment weighting was used to account for baseline between-groups differences. The primary outcome was 3-month good functional outcome (modified Rankin Scale [mRS] score 0-2 or return to baseline modified Rankin Scale). Secondary outcomes were 3-month excellent recovery (modified Rankin Scale score 0-1), symptomatic intracranial hemorrhage, and early neurological deterioration. RESULTS: Overall, 752 patients were included (167 and 585 patients in the BMM+EVT and BMM alone groups, respectively). Median age was 74 (interquartile range, 63-82) years, 329 (44%) patients were female, median National Institutes of Health Stroke Scale was 6 (interquartile range 4-10), and occlusion site was P1 in 188 (25%) and P2 in 564 (75%) patients. Baseline clinical and radiological data were similar between the 2 groups following propensity score weighting. EVT was associated with a trend towards lower odds of good functional outcome (odds ratio, 0.81 [95% CI, 0.66-1.01]; P=0.06) and was not associated with excellent functional outcome (odds ratio, 1.17 [95% CI, 0.95-1.43]; P=0.15). EVT was associated with a higher risk of symptomatic intracranial hemorrhage (odds ratio, 2.51 [95% CI, 1.35-4.67]; P=0.004) and early neurological deterioration (odds ratio, 2.51 [95% CI, 1.64-3.84]; P<0.0001). CONCLUSIONS: In this observational study of patients with proximal posterior cerebral artery occlusion, EVT was not associated with good or excellent functional outcome as compared to BMM alone. However, EVT was associated with higher rates of symptomatic intracranial hemorrhage and early neurological deterioration. EVT should not be routinely recommended in this population, but randomization into a clinical trial is highly warranted.

Endovascular Versus Medical Management of Posterior Cerebral Artery Occlusion Stroke: The PLATO Study.

BACKGROUND: The optimal management of patients with isolated posterior cerebral artery occlusion is uncertain. We compared clinical outcomes for endovascular therapy (EVT) versus medical management (MM) in patients with isolated posterior cerebral artery occlusion. METHODS: This multinational case-control study conducted at 27 sites in Europe and North America included consecutive patients with isolated posterior cerebral artery occlusion presenting within 24 hours of time last well from January 2015 to August 2022. Patients treated with EVT or MM were compared with multivariable logistic regression and inverse probability of treatment weighting. The coprimary outcomes were the 90-day modified Rankin Scale ordinal shift and ≥2-point decrease in the National Institutes of Health Stroke Scale. RESULTS: Of 1023 patients, 589 (57.6%) were male with median (interquartile range) age of 74 (64-82) years. The median (interquartile range) National Institutes of Health Stroke Scale was 6 (3-10). The occlusion segments were P1 (41.2%), P2 (49.2%), and P3 (7.1%). Overall, intravenous thrombolysis was administered in 43% and EVT in 37%. There was no difference between the EVT and MM groups in the 90-day modified Rankin Scale shift (aOR, 1.13 [95% CI, 0.85-1.50]; P=0.41). There were higher odds of a decrease in the National Institutes of Health Stroke Scale by ≥2 points with EVT (aOR, 1.84 [95% CI, 1.35-2.52]; P=0.0001). Compared with MM, EVT was associated with a higher likelihood of excellent outcome (aOR, 1.50 [95% CI, 1.07-2.09]; P=0.018), complete vision recovery, and similar rates of functional independence (modified Rankin Scale score, 0-2), despite a higher rate of SICH and mortality (symptomatic intracranial hemorrhage, 6.2% versus 1.7%; P=0.0001; mortality, 10.1% versus 5.0%; P=0.002). CONCLUSIONS: In patients with isolated posterior cerebral artery occlusion, EVT was associated with similar odds of disability by ordinal modified Rankin Scale, higher odds of early National Institutes of Health stroke scale improvement, and complete vision recovery compared with MM. There was a higher likelihood of excellent outcome in the EVT group despite a higher rate of symptomatic intracranial hemorrhage and mortality. Continued enrollment into ongoing distal vessel occlusion randomized trials is warranted.

Magnetic Resonance Imaging or Computed Tomography for Suspected Acute Stroke: Association of Admission Image Modality with Acute Recanalization Therapies, Workflow Metrics, and Outcomes.

OBJECTIVE: To examine rates of intravenous thrombolysis (IVT), mechanical thrombectomy (MT), door-to-needle (DTN) time, door-to-puncture (DTP) time, and functional outcome between patients with admission magnetic resonance imaging (MRI) versus computed tomography (CT). METHODS: An observational cohort study of consecutive patients using a target trial design within the nationwide Swiss-Stroke-Registry from January 2014 to August 2020 was carried out. Exclusion criteria included MRI contraindications, transferred patients, and unstable or frail patients. Multilevel mixed-effects logistic regression with multiple imputation was used to calculate adjusted odds ratios with 95% confidence intervals for IVT, MT, DTN, DTP, and good functional outcome (mRS 0-2) at 90 days. RESULTS: Of the 11,049 patients included (mean [SD] age, 71 [15] years; 4,811 [44%] women; 69% ischemic stroke, 16% transient ischemic attack, 8% stroke mimics, 6% intracranial hemorrhage), 3,741 (34%) received MRI and 7,308 (66%) CT. Patients undergoing MRI had lower National Institutes of Health Stroke Scale (median [interquartile range] 2 [0-6] vs 4 [1-11]), and presented later after symptom onset (150 vs 123 min, p < 0.001). Admission MRI was associated with: lower adjusted odds of IVT (aOR 0.83, 0.73-0.96), but not with MT (aOR 1.11, 0.93-1.34); longer adjusted DTN (+22 min [13-30]), but not with longer DTP times; and higher adjusted odds of favorable outcome (aOR 1.54, 1.30-1.81). INTERPRETATION: We found an association of MRI with lower rates of IVT and a significant delay in DTN, but not in DTP and rates of MT. Given the delays in workflow metrics, prospective trials are required to show that tissue-based benefits of baseline MRI compensate for the temporal benefits of CT. ANN NEUROL 2022;92:184-194.

Relevance of National Institutes of Health Stroke Scale subitems for best revascularization therapy in minor stroke patients with large vessel occlusion: An observational multicentric study.

BACKGROUND AND PURPOSE: The best management of acute ischemic stroke patients with a minor stroke and large vessel occlusion is still uncertain. Specific clinical and radiological data may help to select patients who would benefit from endovascular therapy (EVT). We aimed to evaluate the relevance of National Institutes of Health Stroke Scale (NIHSS) subitems for predicting the potential benefit of providing EVT after intravenous thrombolysis (IVT; "bridging treatment") versus IVT alone. METHODS: We extracted demographic, clinical, risk factor, radiological, revascularization and outcome data of consecutive patients with M1 or proximal M2 middle cerebral artery occlusion and admission NIHSS scores of 0-5 points, treated with IVT ± EVT between May 2005 and March 2021, from nine prospectively constructed stroke registries at seven French and two Swiss comprehensive stroke centers. Adjusted interaction analyses were performed between admission NIHSS subitems and revascularization modality for two primary outcomes at 3 months: non-excellent functional outcome (modified Rankin Scale score 2-6) and difference in NIHSS score between 3 months and admission. RESULTS: Of the 533 patients included (median age 68.2 years, 46% women, median admission NIHSS score 3), 136 (25.5%) initially received bridging therapy and 397 (74.5%) received IVT alone. Adjusted interaction analysis revealed that only facial palsy on admission was more frequently associated with excellent outcome in patients treated by IVT alone versus bridging therapy (odds ratio 0.47, 95% confidence interval 0.24-0.91; p = 0.013). Regarding NIHSS difference at 3 months, no single NIHSS subitem interacted with type of revascularization. CONCLUSIONS: This retrospective multicenter analysis found that NIHSS subitems at admission had little value in predicting patients who might benefit from bridging therapy as opposed to IVT alone. Further research is needed to identify better markers for selecting EVT responders with minor strokes.

Elevated Hypoperfusion Intensity Ratio (HIR) observed in patients with a large vessel occlusion (LVO) presenting in the evening.

BACKGROUND: Circadian variability has been implicated in timing of stroke onset, yet the full impact of underlying biological rhythms on acute stroke perfusion patterns is not known. We aimed to describe the relationship between time of stroke onset and perfusion profiles in patients with large vessel occlusion (LVO). METHODS: A retrospective observational study was conducted using prospective registries of four stroke centers across North America and Europe with systematic use of perfusion imaging in clinical care. Included patients had stroke due to ICA, M1 or M2 occlusion and baseline perfusion imaging performed within 24h from last-seen-well (LSW). Stroke onset was divided into eight hour intervals: (1) Night: 23:00-6:59, (2) Day: 7:00-14:59, (3) Evening: 15:00-22:59. Core volume was estimated on CT perfusion (rCBF <30%) or DWI-MRI (ADC <620) and the collateral circulation was estimated with the Hypoperfusion Intensity Ratio (HIR = [Tmax>10s]/[Tmax>6s]). Non-parametric testing was conducted using SPSS to account for the non-normalized dependent variables. RESULTS: A total of 1506 cases were included (median age 74.9 years, IQR 63.0-84.0). Median NIHSS, core volumes, and HIR were 14.0 (IQR 8.0-20.0), 13.0mL (IQR 0.0-42.0), and 0.4 (IQR 0.2-0.6) respectively. Most strokes occurred during the Day (n = 666, 44.2%), compared to Night (n = 360, 23.9%), and Evening (n = 480, 31.9%). HIR was highest, indicating worse collaterals, in the Evening compared to the other timepoints (p = 0.006). Controlling for age and time to imaging, Evening strokes had significantly higher HIR compared to Day (p = 0.013). CONCLUSION: Our retrospective analysis suggests that HIR is significantly higher in the evening, indicating poorer collateral activation which may lead to larger core volumes in these patients.

Larger ischemic cores and poor collaterals among large vessel occlusions presenting in the late evening.

BACKGROUND: Components critical to cerebral perfusion have been noted to oscillate over a 24-h cycle. We previously reported that ischemic core volume has a diurnal relationship with stroke onset time when examined as dichotomized epochs (i.e. Day, Evening, Night) in a cohort of over 1,500 large vessel occlusion (LVO) patients. In this follow-up analysis, our goal was to explore if there is a sinusoidal relationship between ischemic core, collateral status (as measured by HIR), and stroke onset time. METHODS: We retrospectively examined collection of LVO patients with baseline perfusion imaging performed within 24 h of stroke onset from four international comprehensive stroke centers. Both ischemic core volume and HIR, were utilized as the primary radiographic parameters. To evaluate for differences in these parameters over a continuous 24-h cycle, we conducted a sinusoidal regression analysis after linearly regressing out the confounders age and time to imaging. RESULTS: A total of 1506 LVO cases were included, with a median ischemic core volume of 13.0 cc (IQR: 0.0-42.0) and median HIR of 0.4 (IQR: 0.2-0.6). Ischemic core volume varied by stroke onset time in the unadjusted (p = 0.001) and adjusted (p = 0.003) sinusoidal regression analysis with a peak in core volume around 7:45PM. HIR similarly varied by stroke onset time in the unadjusted (p = 0.004) and adjusted (p = 0.002) models with a peak in HIR values at around 8:18PM. CONCLUSION: The results suggest that critical factors to the development of the ischemic core vary by stroke onset time and peak around 8PM. When placed in the context of prior studies, strongly suggest a diurnal component to the development of the ischemic core.