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.

No-reflow phenomenon in stroke patients: A systematic literature review and meta-analysis of clinical data.

BACKGROUND: The no-reflow phenomenon refers to the absence of microvascular reperfusion despite macrovascular reperfusion. AIM: The aim of this analysis was to summarize the available clinical evidence on no-reflow in patients with acute ischemic stroke. METHODS: A systematic literature review and a meta-analysis of clinical data on definition, rates, and impact of the no-reflow phenomenon after reperfusion therapy was carried out. A predefined research strategy was formulated according to the Population, Intervention, Comparison, and Outcome (PICO) model and was used to screen for articles in PubMed, MEDLINE, and Embase up to 8 September 2022. Whenever possible, quantitative data were summarized using a random-effects model. RESULTS: Thirteen studies with a total of 719 patients were included in the final analysis. Most studies (n = 10/13) used variations of the Thrombolysis in Cerebral Infarction scale to evaluate macrovascular reperfusion, whereas microvascular reperfusion and no-reflow were mostly assessed on perfusion maps (n = 9/13). In one-third of stroke patients with successful macrovascular reperfusion (29%, 95% confidence interval (CI), 21-37%), the no-reflow phenomenon was observed. Pooled analysis showed that no-reflow was consistently associated with reduced rates of functional independence (odds ratio (OR), 0.21, 95% CI, 0.15-0.31). CONCLUSION: The definition of no-reflow varied substantially across studies, but it appears to be a common phenomenon. Some of the no-reflow cases may simply represent remaining vessel occlusions, and it remains unclear whether no-reflow is an epiphenomenon of the infarcted parenchyma or causes infarction. Future studies should focus on standardizing the definition of no-reflow with more consistent definitions of successful macrovascular reperfusion and experimental set-ups that could detect the causality of the observed findings.

Sustaining a New Model of Acute Stroke Care: A Mixed-Method Process Evaluation of the Melbourne Mobile Stroke Unit.

BACKGROUND: Internationally, Mobile Stroke Unit (MSU) ambulances have changed pre-hospital acute stroke care delivery. MSU clinical and cost-effectiveness studies are emerging, but little is known about important factors for achieving sustainability of this innovative model of care. METHODS: Mixed-methods study from the Melbourne MSU (operational since November 2017) process evaluation. Participant purposive sampling included clinical, operational and executive/management representatives from Ambulance Victoria (AV) (emergency medical service provider), the MSU clinical team, and receiving hospitals. Sustainability was defined as ongoing MSU operations, including MSU workforce and future model considerations. Theoretically-based on-line survey with Unified Theory of Acceptance and Use of Technology (UTAUT), Self Determination Theory (SDT, Intrinsic Motivation), and open-text questions targeting barriers and benefits was administered (June-September 2019). Individual/group interviews were conducted, eliciting improvement suggestions and requirements for ongoing use. Descriptive and regression analyses (quantitative data) and directed content and thematic analysis (open text and interview data) were conducted. RESULTS: There were 135 surveys completed. Identifying that the MSU was beneficial to daily work (ß=0.61), not experiencing pressure/tension about working on the MSU (ß=0.17) and thinking they did well working within the team model (ß=0.17) were significantly associated with wanting to continue working within the MSU model [R2=0.76; F(15, 60)=12.76, P<.001]. Experiences varied between those on the MSU team and those working with the MSU. Advantages were identified for patients (better, faster care) and clinicians (interdisciplinary learning). Disadvantages included challenges integrating into established systems, and establishing working relationships. Themes identified from 35 interviews were MSU team composition, MSU vehicle design and layout, personnel recruitment and rostering, communication improvements between organisations, telemedicine options, MSU operations and dispatch specificity. CONCLUSION: Important factors affecting the sustainability of the MSU model of stroke care emerged. A cohesive team approach, with identifiable benefits and good communication between participating organisations is important for clinical and operational sustainability.

Occult contrast retention post-thrombectomy on 24-h follow-up dual-energy CT: Associations and impact on imaging analysis.

BACKGROUND: Following reperfusion treatment in ischemic stroke, computed tomography (CT) imaging at 24 h is widely used to assess radiological outcomes. Even without visible hyperattenuation, occult angiographic contrast may persist in the brain and confound Hounsfield unit-based imaging metrics, such as net water uptake (NWU). AIMS: We aimed to assess the presence and factors associated with retained contrast post-thrombectomy on 24-h imaging using dual-energy CT (DECT), and its impact on the accuracy of NWU as a measure of cerebral edema. METHODS: Consecutive patients with anterior circulation large vessel occlusion who had post-thrombectomy DECT performed 24-h post-treatment from two thrombectomy stroke centers were retrospectively studied. NWU was calculated by interside comparison of HUs of the infarct lesion and its mirror homolog. Retained contrast was quantified by the difference in NWU values with and without adjustment for iodine. Patients with visible hyperdensities from hemorrhagic transformation or visible contrast retention and bilateral infarcts were excluded. Cerebral edema was measured by relative hemispheric volume (rHV) and midline shift (MLS). RESULTS: Of 125 patients analyzed (median age 71 (IQR = 61-80), baseline National Institutes of Health Stroke Scale (NIHSS) 16 (IQR = 9.75-21)), reperfusion (defined as extended-Thrombolysis-In-Cerebral-Infarction 2b-3) was achieved in 113 patients (90.4%). Iodine-subtracted NWU was significantly higher than unadjusted NWU (17.1% vs 10.8%, p < 0.001). In multivariable median regression analysis, increased age (p = 0.024), number of passes (p = 0.006), final infarct volume (p = 0.023), and study site (p = 0.021) were independently associated with amount of retained contrast. Iodine-subtracted NWU correlated with rHV (rho = 0.154, p = 0.043) and MLS (rho = 0.165, p = 0.033) but unadjusted NWU did not (rHV rho = -0.035, p = 0.35; MLS rho = 0.035, p = 0.347). CONCLUSIONS: Angiographic iodine contrast is retained in brain parenchyma 24-h post-thrombectomy, even without visually obvious hyperdensities on CT, and significantly affects NWU measurements. Adjustment for retained iodine using DECT is required for accurate NWU measurements post-thrombectomy. Future quantitative studies analyzing CT after thrombectomy should consider occult contrast retention.

Cost-effectiveness of tenecteplase versus alteplase for stroke thrombolysis evaluation trial in the ambulance.

BACKGROUND: Tenecteplase administered to patients with ischaemic stroke in a mobile stroke unit (MSU) has been shown to reduce the perfusion lesion volumes and result in ultra-early recovery. We now seek to assess the cost-effectiveness of tenecteplase in the MSU. METHODS: A within-trial (TASTE-A) economic analysis and a model-based long-term cost-effectiveness analysis were performed. This post hoc within-trial economic analysis utilised the patient-level data (intention to treat, ITT) prospectively collected over the trial to calculate the difference in both healthcare costs and quality-adjusted life years (QALYs, estimated from modified Rankin scale score). A Markov microsimulation model was developed to simulate the long-term costs and benefits. RESULTS: In total, there were 104 patients with ischaemic stroke randomised to tenecteplase (n = 55) or alteplase (n = 49) treatment groups, respectively in the TASTE-A trial. The ITT-based analysis showed that treatment with tenecteplase was associated with non-signficantly lower costs (A$28,903 vs A$40,150 (p = 0.056)) and greater benefits (0.171 vs 0.158 (p = 0.457)) than that for the alteplase group over the first 90 days post the index stroke. The long-term model showed that tenecteplase led to greater savings in costs (-A$18,610) and more health benefits (0.47 QALY or 0.31 LY gains). Tenecteplase-treated patients had reduced costs for rehospitalisation (-A$1464), nursing home care (-A$16,767) and nonmedical care (-A$620) per patient. CONCLUSIONS: Treatment of ischaemic stroke patients with tenecteplase appeared to be cost-effective and improve QALYs in the MSU setting based on Phase II data. The reduced total cost from tenecteplase was driven by savings from acute hospitalisation and reduce need for nursing home care.

Twenty years of monitoring acute stroke care in Australia through the national stroke audit programme (1999-2019): A cross-sectional study.

BACKGROUND: National organisational surveys and clinical audits to monitor and guide improvements to the delivery of evidence-based acute stroke care have been undertaken in Australia since 1999. This study aimed to determine the association between repeated national audit cycles on stroke service provision and care delivery from 1999 to 2019. METHODS: Cross-sectional study using data from organisational surveys (1999, 2004, 2007-2019) and clinical data from the biennial National Stroke Acute Audit (2007-2019). Age-, sex-, and stroke severity-adjusted proportions were reported for adherence to guideline-recommended care processes. Multivariable, logistic regression models were performed to determine the association between repeated audit cycles and service provision (organisational) and care delivery (clinical). RESULTS: Overall, 197 hospitals provided organisational survey data (1999-2019), with 24,996 clinical cases from 136 hospitals (around 40 cases per audit) (2007-2019). We found significant improvements in service organisation between 1999 and 2019 for access to stroke units (1999: 42%, 2019: 81%), thrombolysis services (1999: 6%, 2019: 85%), and rapid assessment/management for patients with transient ischaemic attack (1999: 11%, 2019: 61%). Analyses of patient-level audits for 2007 to 2019 found the odds of receiving care processes per audit cycle to have significantly increased for thrombolysis (2007: 3%, 2019: 11%; OR 1.15, 95% CI 1.13, 1.17), stroke unit access (2007: 52%, 2019: 69%; OR 1.15, 95% CI 1.14, 1.17), risk factor advice (2007: 40%, 2019: 63%; OR 1.10, 95% CI 1.09, 1.12), and carer training (2007: 24%, 2019: 51%; OR 1.12, 95% CI 1.10, 1.15). CONCLUSIONS: Between 1999 and 2019, the quality of acute stroke care in Australia has improved in line with best practice evidence. Standardised monitoring of stroke care can inform targeted efforts to reduce identified gaps in best practice, and illustrate the evolution of the health system for stroke.

Tenecteplase versus alteplase for stroke thrombolysis evaluation (TASTE): A multicentre, prospective, randomized, open-label, blinded-endpoint, controlled phase III non-inferiority trial protocol.

RATIONALE: Alteplase is the only approved thrombolytic agent for acute stroke. An alternative plasminogen activator, tenecteplase, has been previously shown to increase early biological effectiveness (reperfusion) resulting in early clinical recovery in acute stroke patients with target mismatch on perfusion imaging; however, phase III data are lacking. AIM AND HYPOTHESIS: In this study, we assess the efficacy and safety of tenecteplase compared to alteplase in acute stroke patients with target mismatch on perfusion imaging. METHODS AND DESIGN: Tenecteplase (0.25 mg/kg) versus alteplase (0.9 mg/kg) for Stroke Thrombolysis Evaluation (TASTE) is a multicentre, prospective, randomized, open-label, blinded-endpoint (PROBE), controlled phase III non-inferiority trial (2 arms with 1:1 randomization) with an adaptive sample size re-estimation in patients with acute ischemic stroke meeting target mismatch criteria on perfusion imaging. SAMPLE SIZE ESTIMATES: Recruiting 728 patients (1:1 tenecteplase vs alteplase) would yield 90% power (two-sided alpha 0.05) to detect a treatment effect of 8% (26% modified Rankin scale (mRS) 0-1 in alteplase arm and 34% mRS 0-1 in tenecteplase arm), with an absolute non-inferiority margin of 3%. Following the pre-planned "promising zone" adaptive sample size re-estimation, the final sample size was set at 832 patients. STUDY OUTCOMES: The primary outcome measure is the proportion of patients with an mRS score of 0-1 at 3 months. Secondary outcomes include the categorical shift in mRS at 3 months; the proportion of patients with: mRS 0-2, 5-6, and 6; reduction of the National Institutes of Health Stroke Scale (NIHSS) by 8 or more points or reaching 0-1 at 24 h; symptomatic intracerebral hemorrhage within 36 h; and death. DISCUSSION: This pivotal trial will provide important data on the role of tenecteplase in acute ischemic stroke, and the use of imaging-based treatment decision-making for stroke thrombolysis. CLINICAL TRIAL PROTOCOL: Trial Registration: ACTRN12613000243718, EudraCT 2015-002657-36.

Enhancing generalizability of stroke clinical trial results: Illustrations from upper-limb motor recovery trials.

INTRODUCTION: Broadening eligibility criteria has been a focus to increase the generalizability of trial findings. Using upper-limb motor trials conducted early post-stroke as the illustrative domain, we sought to (1) investigate whether the published aim and conclusion statements adequately reflect the generalizability of findings and (2) explore internal validity and feasibility as constraints to achieving generalizability. METHODS: We systematically applied a conceptual model of a trial sampling process to published literature from systematic review and prospective cross-sectional data. The eligibility criteria reported and used to exclude patients were classified by consensus as related to safety, internal validity, feasibility, or a combination thereof. Categorical data were reported as counts/proportions, and continuous data were reported as median (interquartile range (IQR)). RESULTS: Thirty trials (n = 1638 participants) were included in the published literature and 1013 patients in the prospective data set. Thirty-seven percent of trials did not describe their target population in the aim and conclusion, and 80% did not report all trial screening data. Eligibility criteria related to internal validity were the most common type reported and applied to exclude patients across both data sets. In the prospective data set, 70% of patients were excluded for more than one reason. CONCLUSION: Key information to support the generalizability of trial findings was insufficiently reported in published upper-limb motor research conducted early post-stroke. Broadening eligibility criteria alone is unlikely to sufficiently improve trial inclusivity due to internal validity constraints. Trials could achieve inclusivity through targeting multiple sub-populations, that in combination, produce clinically relevant results that are applicable to a broader population.

A Phase III, prospective, double-blind, randomized, placebo-controlled trial of thrombolysis in imaging-eligible, late-window patients to assess the efficacy and safety of tenecteplase (TIMELESS): Rationale and design.

RATIONALE: While thrombolysis is standard of care for patients with acute ischemic stroke (AIS) within 4.5 h of symptom onset, the benefit of tenecteplase beyond this time window is less certain. AIM: The TIMELESS trial (NCT03785678) aims to determine if treatment with tenecteplase increases the proportion of good clinical outcomes among patients with stroke due to a large vessel occlusion who present beyond 4.5 h after symptom onset. SAMPLE SIZE ESTIMATES: A total of 456 patients will provide ⩾90% power to detect differences in the distribution of modified Rankin Scale scores at Day 90 at the two-sided 0.049 significance level. METHODS AND DESIGN: TIMELESS is a Phase III, double-blind, randomized, placebo-controlled trial of tenecteplase with or without endovascular thrombectomy in patients with AIS and evidence of salvageable tissue via imaging who present within the 4.5- to 24-h time window with an internal carotid artery (ICA) or middle cerebral artery (MCA) (M1/M2) occlusion. STUDY OUTCOMES: The primary efficacy objective of tenecteplase compared with placebo will be evaluated with ordinal modified Rankin Scale scores at Day 90. Safety will be evaluated via incidence of symptomatic intracranial hemorrhage, incidence and severity of adverse events, and mortality rate. DISCUSSION: Results from TIMELESS will contribute to understanding of the safety and efficacy of tenecteplase administered 4.5-24 h following symptom onset for patients with an ICA or MCA occlusion.

Outcome prediction in large vessel occlusion ischemic stroke with or without endovascular stroke treatment: THRIVE-EVT.

INTRODUCTION: The THRIVE score and the THRIVE-c calculation are validated ischemic stroke outcome prediction tools based on patient variables that are readily available at initial presentation. Randomized controlled trials (RCTs) have demonstrated the benefit of endovascular treatment (EVT) for many patients with large vessel occlusion (LVO), and pooled data from these trials allow for adaptation of the THRIVE-c calculation for use in shared clinical decision making regarding EVT. METHODS: To extend THRIVE-c for use in the context of EVT, we extracted data from the Virtual International Stroke Trials Archive (VISTA) from 7 RCTs of EVT. Models were built in a randomly selected development cohort using logistic regression that included the predictors from THRIVE-c: age, NIH Stroke Scale (NIHSS) score, presence of hypertension, diabetes mellitus, and/or atrial fibrillation, as well as randomization to EVT and, where available, the Alberta Stroke Program Early CT Score (ASPECTS). RESULTS: Good outcome was achieved in 366/787 (46.5%) of subjects randomized to EVT and in 236/795 (29.7%) of subjects randomized to control (P < 0.001), and the improvement in outcome with EVT was seen across age, NIHSS, and THRIVE-c good outcome prediction. Models to predict outcome using THRIVE elements (age, NIHSS, and comorbidities) together with EVT, with or without ASPECTS, had similar performance by ROC analysis in the development and validation cohorts (THRIVE-EVT ROC area under the curve (AUC) = 0.716 in development, 0.727 in validation, P = 0.30; THRIVE-EVT + ASPECTS ROC AUC = 0.718 in development, 0.735 in validation, P = 0.12). CONCLUSION: THRIVE-EVT may be used alongside the original THRIVE-c calculation to improve outcome probability estimation for patients with acute ischemic stroke, including patients with or without LVO, and to model the potential improvement in outcomes with EVT for an individual patient based on variables that are available at initial presentation. Online calculators for THRIVE-c estimation are available at www.thrivescore.org and www.mdcalc.com/thrive-score-for-stroke-outcome.

Effect of the Shanghai Stroke Service System (4S) on the quality of stroke care and outcomes: A prospective quality improvement project.

BACKGROUND: In China, disparities in the quality of stroke care still exist and implementing quality improvement is still a challenge. AIM: The aim of the study was to determine whether the intervention by Shanghai Stroke Service System (4S) has helped improve adherence to stroke care guidelines and patient outcome. METHODS: The 4S is a regional stroke network with real-time data extraction among its 61 stroke centers in Shanghai. A total of 11 key performance indicators (KPIs) were evaluated. The primary outcomes were a composite measure and an all-or-none measure of adherence to 11 KPIs. The secondary outcomes were length of hospital stay and in-hospital mortality. RESULTS: The study enrolled 92,395 patients (mean age 69.0 ± 12.5 years, 65.2% men) with acute ischemic stroke hospitalized within 7 days of onset in Shanghai from January 2015 to December 2020. More patients received guideline recommended care between 2018 and 2020 than those between 2015 and 2017 (composite measure 87.1% vs 83.6%; absolute difference 2.9%, 95% confidence interval (CI) = [2.7%, 3.2%], p < 0.001; all-or-none measure 49.2% vs 44.8% patients; absolute difference 3.5%, 95% CI = [2.7%, 4.2%], p < 0.001). Further analysis of individual KPIs showed an absolute increase in six KPIs ranging from 3.4% to 8.9% (p < 0.001 for all comparisons). Compared with 2015-2017, hospital length of stay was shorter (10.95 vs 11.90 days; absolute difference -1.08, 95% CI = [-1.18, -0.99], p < 0.001), and in-hospital mortality was significantly reduced (risk ratio (RR) = 0.88, 95% CI = [0.79, 0.98], p = 0.01) in 2018-2020. CONCLUSION: The 4S intervention was associated with increased adherence to the stroke care guidelines, which further translated to improved clinical outcomes. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02735226.

Cost-effectiveness of CT perfusion for patients with acute ischemic stroke (CLEOPATRA)-Study protocol for a healthcare evaluation study.

Introduction: Computed tomography perfusion (CTP) is variably considered to assess eligibility for endovascular thrombectomy (EVT) in acute ischemic (AIS) stroke patients. Although CTP is recommended for patient selection in later (6-24 h) time window, it is currently not recommended in the earlier (0-6 h) time window and the costs and health effects of including CTP for EVT selection remain unknown. We aim to estimate the costs and health effects of using CTP for EVT selection in AIS patients compared to conventional selection. Patients and methods: CLEOPATRA is a healthcare evaluation study using clinical and imaging data from multiple, prospective EVT trials and registries in both the earlier and later time windows. To study the long-term health and cost effects, we will construct a ("Markov") health state transition model simulating the clinical outcome over a 5-year follow-up period for CTP-based and conventional selection for EVT. Clinical data acquired within the current study and estimates from the literature will be used as input for probabilities of events, costs, and Quality-Adjusted Life Years (QALYs) per modified Rankin Scale (mRS) subscore. Primary outcome for the cost-effectiveness analysis will be the Incremental Cost-Effectiveness Ratio (ICER) in terms of costs per QALY gained over the simulated follow-up period. Study outcomes: Outcome measures will be reported as cumulative values over a 5-year follow-up period. Discussion: This study will provide preliminary insight into costs and health effects of including CTP in the selection for EVT for AIS patients, presenting between 0 and 24 h after time last known well. The results may be used to develop recommendations and inform further implementation projects and studies.

Does tranexamic acid affect intraventricular hemorrhage growth in acute ICH? An analysis of the STOP-AUST trial.

Background: Trials of tranexamic acid (TXA) in acute intracerebral hemorrhage (ICH) have focused on the imaging outcomes of intraparenchymal hematoma growth. However, intraventricular hemorrhage (IVH) growth is also strongly associated with outcome after ICH. Revised definitions of hematoma expansion incorporating IVH growth have been proposed. Aims: We sought to evaluate the effect of TXA on IVH growth. Methods: We analyzed data from the STOP-AUST trial, a prospective randomized trial comparing TXA to placebo in ICH patients presenting ≤ 4.5 h from symptom onset with a CT-angiography spot sign. New IVH development at follow-up, any interval IVH growth, and IVH growth ≥ 1 mL were compared between the treatment groups using logistic regression. The treatment effect of TXA against placebo using conventional (> 6 mL or 33%), and revised definitions of hematoma expansion (> 6 mL or 33% or IVH expansion ≥ 1 mL, > 6 mL or 33%, or any IVH expansion, and > 6 mL or 33% or new IVH development) were also assessed. Treatment effects were adjusted for baseline ICH volume. Results: The analysis population consisted of 99 patients (50 placebo, 49 TXA). New IVH development at follow-up was observed in 6/49 (12%) who received TXA and 13/50 (26%) who received placebo (aOR: 0.38 [95% CI: 0.13-1.13]). Any interval IVH growth was observed in 12/49 (25%) who received TXA versus 26/50 (32%) receiving placebo (aOR: 0.69 [95% CI: 0.28-1.66]). IVH growth ≥ 1 mL did not differ between the two groups. Using revised definitions of hematoma expansion, no significant difference in treatment effect was observed between TXA and placebo. Conclusions: IVH may be attenuated by TXA following ICH; however, studies with larger cohorts are required to investigate this further. Registration: http://www.clinicaltrials.gov; Unique identifier: NCT01702636.

Threat of COVID-19 impacting on a quaternary healthcare service: a retrospective cohort study of administrative data.

OBJECTIVES: The threat of a pandemic, over and above the disease itself, may have significant and broad effects on a healthcare system. We aimed to describe the impact of the SARS-CoV-2 pandemic (during a relatively low transmission period) and associated societal restrictions on presentations, admissions and outpatient visits. DESIGN: We compared hospital activity in 2020 with the preceding 5 years, 2015-2019, using a retrospective cohort study design. SETTING: Quaternary hospital in Melbourne, Australia. PARTICIPANTS: Emergency department presentations, hospital admissions and outpatient visits from 1 January 2015 to 30 June 2020, n=896 934 episodes of care. INTERVENTION: In Australia, the initial peak COVID-19 phase was March-April. PRIMARY AND SECONDARY OUTCOME MEASURES: Separate linear regression models were fitted to estimate the impact of the pandemic on the number, type and severity of emergency presentations, hospital admissions and outpatient visits. RESULTS: During the peak COVID-19 phase (March and April 2020), there were marked reductions in emergency presentations (10 389 observed vs 14 678 expected; 29% reduction; p<0.05) and hospital admissions (5972 observed vs 8368 expected; 28% reduction; p<0.05). Stroke (114 observed vs 177 expected; 35% reduction; p<0.05) and trauma (1336 observed vs 1764 expected; 24% reduction; p<0.05) presentations decreased; acute myocardial infarctions were unchanged. There was an increase in the proportion of hospital admissions requiring intensive care (7.0% observed vs 6.0% expected; p<0.05) or resulting in death (2.2% observed vs 1.5% expected; p<0.05). Outpatient attendances remained similar (30 267 observed vs 31 980 expected; 5% reduction; not significant) but telephone/telehealth consultations increased from 2.5% to 45% (p<0.05) of total consultations. CONCLUSIONS: Although case numbers of COVID-19 were relatively low in Australia during the first 6 months of 2020, the impact on hospital activity was profound.

Association between pre-treatment perfusion profile and cerebral edema after reperfusion therapies in ischemic stroke.

The relationship between reperfusion and edema is unclear, with experimental and clinical data yielding conflicting results. We investigated whether the extent of salvageable and irreversibly-injured tissue at baseline influenced the effect of therapeutic reperfusion on cerebral edema. In a pooled analysis of 415 patients with anterior circulation large vessel occlusion from the Tenecteplase-versus-Alteplase-before-Endovascular-Therapy-for-Ischemic-Stroke (EXTEND-IA TNK) part 1 and 2 trials, associations between core and mismatch volume on pre-treatment CT-Perfusion with cerebral edema at 24-hours, and their interactions with reperfusion were tested. Core volume was associated with increased edema (p < 0.001) with no significant interaction with reperfusion (p = 0.82). In comparison, a significant interaction between reperfusion and mismatch volume (p = 0.03) was observed: Mismatch volume was associated with increased edema in the absence of reperfusion (p = 0.009) but not with reperfusion (p = 0.27). When mismatch volume was dichotomized at the median (102 ml), reperfusion was associated with reduced edema in patients with large mismatch volume (p < 0.001) but not with smaller mismatch volume (p = 0.35). The effect of reperfusion on edema may be variable and dependent on the physiological state of the cerebral tissue. In patients with small to moderate ischemic core volume, the benefit of reperfusion in reducing edema is related to penumbral salvage.

Pre-stroke physical activity and admission stroke severity: A systematic review.

BACKGROUND: Admission stroke severity is an important clinical predictor of stroke outcomes. Pre-stroke physical activity contributes to stroke prevention and may also be associated with reduced stroke severity. Summarizing the evidence to date will inform strategies to reduce burden after stroke. AIMS: To summarize the published evidence for the relationship between pre-stroke physical activity and admission stroke severity and to provide recommendations for future research. SUMMARY OF REVIEW: MEDLINE, Embase, Emcare, CENTRAL, and gray literature databases were searched on 14 February 2020 using search terms related to stroke and pre-stroke physical activity in adult stroke survivors. We screened 8,152 references and assessed 172 full-text references for eligibility. We included seven studies (n = 41,800 stroke survivors). All studies were observational, assessed pre-stroke physical activity using self-reported questionnaires, and assessed admission stroke severity using the National Institute of Health Stroke Scale. Analyses were categorized as the presence of pre-stroke physical activity (four studies) or dose-response (five studies). In three studies, presence of pre-stroke physical activity was associated with milder stroke severity, and no association in one study. Greater pre-stroke physical activity duration and intensity (two studies) or amount (three studies) were associated with milder stroke severity. Studies ranged between moderate to critical risk of bias, primarily due to confounding factors. Pre-stroke physical activity may be associated with reduced risk factors for severe stroke, distal occlusion, smaller infarcts, and shorter time-to-treatment delivery. CONCLUSION: Pre-stroke physical activity may be associated with reduced admission stroke severity. Lack of randomized controlled trials limited causality conclusions. Future research recommendations were provided.

Call to Action: SARS-CoV-2 and CerebrovAscular DisordErs (CASCADE).

BACKGROUND AND PURPOSE: The novel severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2), now named coronavirus disease 2019 (COVID-19), may change the risk of stroke through an enhanced systemic inflammatory response, hypercoagulable state, and endothelial damage in the cerebrovascular system. Moreover, due to the current pandemic, some countries have prioritized health resources towards COVID-19 management, making it more challenging to appropriately care for other potentially disabling and fatal diseases such as stroke. The aim of this study is to identify and describe changes in stroke epidemiological trends before, during, and after the COVID-19 pandemic. METHODS: This is an international, multicenter, hospital-based study on stroke incidence and outcomes during the COVID-19 pandemic. We will describe patterns in stroke management, stroke hospitalization rate, and stroke severity, subtype (ischemic/hemorrhagic), and outcomes (including in-hospital mortality) in 2020 during COVID-19 pandemic, comparing them with the corresponding data from 2018 and 2019, and subsequently 2021. We will also use an interrupted time series (ITS) analysis to assess the change in stroke hospitalization rates before, during, and after COVID-19, in each participating center. CONCLUSION: The proposed study will potentially enable us to better understand the changes in stroke care protocols, differential hospitalization rate, and severity of stroke, as it pertains to the COVID-19 pandemic. Ultimately, this will help guide clinical-based policies surrounding COVID-19 and other similar global pandemics to ensure that management of cerebrovascular comorbidity is appropriately prioritized during the global crisis. It will also guide public health guidelines for at-risk populations to reduce risks of complications from such comorbidities.

Improving acute stroke care in regional hospitals: clinical evaluation of the Victorian Stroke Telemedicine program.

OBJECTIVES: To evaluate the impact of the Victorian Stroke Telemedicine (VST) program during its first 12 months on the quality of care provided to patients presenting with suspected stroke to hospitals in regional Victoria. DESIGN: Historical controlled cohort study comparing outcomes during a 12-month control period with those for the initial 12 months of full implementation of the VST program at each hospital. SETTING: 16 hospitals in regional Victoria that participated in the VST program between 1 January 2010 and 30 January 2016. PARTICIPANTS: Adult patients with suspected stroke presenting to the emergency departments of the participating hospitals. MAIN OUTCOME MEASURES: Indicators for key processes of care, including symptom onset-to-arrival, door-to-first medical review, and door-to-CT times; provision and timeliness of provision of thrombolysis to patients with ischaemic stroke. RESULTS: 2887 patients with suspected stroke presented to participating emergency departments during the control period, 3178 during the intervention period; the patient characteristics were similar for both periods. A slightly larger proportion of patients with ischaemic stroke who arrived within 4.5 hours of symptom onset received thrombolysis during the intervention than during the control period (37% v 30%). Door-to-CT scan time (median, 25 min [IQR, 13-49 min] v 34 min [IQR, 18-76 min]) and door-to-needle time for stroke thrombolysis (73 min [IQR, 56-96 min] v 102 min [IQR, 77-128 min]) were shorter during the intervention. The proportions of patients who received thrombolysis and had a symptomatic intracerebral haemorrhage (4% v 16%) or died in hospital (6% v 20%) were smaller during the intervention period. CONCLUSIONS: Telemedicine has provided Victorian regional hospitals access to expert care for emergency department patients with suspected acute stroke. Eligible patients with ischaemic stroke are now receiving stroke thrombolysis more quickly and safely.