Stroke in the Time of Circadian Medicine.

Time-of-day significantly influences the severity and incidence of stroke. Evidence has emerged not only for circadian governance over stroke risk factors, but also for important determinants of clinical outcome. In this review, we provide a comprehensive overview of the interplay between chronobiology and cerebrovascular disease. We discuss circadian regulation of pathophysiological mechanisms underlying stroke onset or tolerance as well as in vascular dementia. This includes cell death mechanisms, metabolism, mitochondrial function, and inflammation/immunity. Furthermore, we present clinical evidence supporting the link between disrupted circadian rhythms and increased susceptibility to stroke and dementia. We propose that circadian regulation of biochemical and physiological pathways in the brain increase susceptibility to damage after stroke in sleep and attenuate treatment effectiveness during the active phase. This review underscores the importance of considering circadian biology for understanding the pathology and treatment choice for stroke and vascular dementia and speculates that considering a patient's chronotype may be an important factor in developing precision treatment following stroke.

Mode of Onset Modifies the Effect of Time to Endovascular Reperfusion on Clinical Outcomes after Acute Ischemic Stroke: An Analysis of the DAWN Trial.

OBJECTIVE: We aimed to assess the impact of time to endovascular thrombectomy (EVT) on clinical outcomes in the DAWN trial, while also exploring the potential effect modification of mode of stroke onset on this relationship. METHODS: The association between every 1-h treatment delay with 90-day functional independence (modified Rankin Scale [mRS] score 0-2), symptomatic intracranial hemorrhage, and 90-day mortality was explored in the overall population and in three modes of onset subgroups (wake-up vs. witnessed vs. unwitnessed). RESULTS: Out of the 205 patients, 98 (47.8%) and 107 (52.2%) presented in the 6 to 12 hours and 12 to 24 hours time window, respectively. Considering all three modes of onset together, there was no statistically significant association between time last seen well to randomization with either functional independence or mortality at 90 days in either the endovascular thrombectomy (mRS 0-2 1-hour delay OR 1.07; 95% CI 0.93-1.24; mRS 6 OR 0.84; 95% CI 0.65-1.03) or medical management (mRS 0-2 1-hour delay OR 0.98; 95% CI 0.80-1.14; mRS 6 1-hour delay OR 0.94; 95% CI 0.79-1.09) groups. Moreover, there was no significant interaction between treatment effect and time (p = 0.439 and p = 0.421 for mRS 0-2 and 6, respectively). However, within the thrombectomy group, the models that tested the association between time last seen well to successful reperfusion (modified Treatment in Cerebral Infarction ≥2b) and 90-day functional independence showed a significant interaction with mode of presentation (p = 0.013). This appeared to be driven by a nominally positive slope for both witnessed and unwitnessed strokes versus a significantly (p = 0.018) negative slope in wake-up patients. There was no association between treatment times and symptomatic intracranial hemorrhage. INTERPRETATION: Mode of onset modifies the effect of time to reperfusion on thrombectomy outcomes, and should be considered when exploring different treatment paradigms in the extended window. ANN NEUROL 2024;96:356-364.

Golden Hour Intravenous Thrombolysis for Acute Ischemic Stroke: A Systematic Review and Meta-Analysis.

OBJECTIVES: The benefits of intravenous thrombolysis are time-dependent, with maximum efficacy when administered within the first "golden" hour after onset. Nevertheless, the impact of golden hour thrombolysis has not been well quantified. METHODS: Medline, Embase, and Web of Science databases were systematically searched from inception to August 27, 2023. We included studies that reported safety and efficacy outcomes of ischemic stroke patients treated with intravenous thrombolysis in the golden hour versus later treatment window. The primary outcome was an excellent functional outcome, defined as a modified Rankin Scale score of 0-1 at 90 days. The secondary efficacy outcome was a good functional outcome (defined as modified Rankin Scale score of 0-2). The main safety outcome was symptomatic intracerebral hemorrhage. RESULTS: Seven studies involving 78,826 patients met the selection criteria. Golden hour thrombolysis was associated with higher odds of 90-day excellent functional outcomes (OR 1.40, 95% CI 1.16-1.67) and 90-day good functional outcomes (OR 1.38, 95% CI 1.13-1.69) compared with thrombolysis outside the golden hour. The number needed to treat to benefit for golden hour thrombolysis to reduce disability by at least 1 level on the modified Rankin Scale per patient was 2.6. Rates of symptomatic intracerebral hemorrhage and mortality were similar between groups. INTERPRETATION: Golden hour thrombolysis significantly improved acute ischemic stroke outcomes. The findings provide rationale for intensive efforts aimed at expediting thrombolytic therapy within the golden hour window following the onset of acute ischemic stroke. ANN NEUROL 2024;96:582-590.

Strokes Averted by Intravenous Thrombolysis: A Secondary Analysis of a Prospective, Multicenter, Controlled Trial of Mobile Stroke Units.

OBJECTIVE: This study was undertaken to examine averted stroke in optimized stroke systems. METHODS: This secondary analysis of a multicenter trial from 2014 to 2020 compared patients treated by mobile stroke unit (MSU) versus standard management. The analytical cohort consisted of participants with suspected stroke treated with intravenous thrombolysis. The main outcome was a tissue-defined averted stroke, defined as a final diagnosis of stroke with resolution of presenting symptoms/signs by 24 hours attributed to thrombolysis and no acute infarction/hemorrhage on imaging. An additional outcome was stroke with early symptom resolution, defined as a final diagnosis of stroke with resolution of presenting symptoms/signs by 24 hours attributed to thrombolysis. RESULTS: Among 1,009 patients with a median last known well to thrombolysis time of 87 minutes, 159 (16%) had tissue-defined averted stroke and 276 (27%) had stroke with early symptom resolution. Compared with standard management, MSU care was associated with more tissue-defined averted stroke (18% vs 11%, adjusted odds ratio [aOR] = 1.82, 95% confidence interval [CI] = 1.13-2.98) and stroke with early symptom resolution (31% vs 21%, aOR = 1.74, 95% CI = 1.12-2.61). The relationships between thrombolysis treatment time and averted/early recovered stroke appeared nonlinear. Most models indicated increased odds for stroke with early symptom resolution but not tissue-defined averted stroke with earlier treatment. Additionally, younger age, female gender, hyperlipidemia, lower National Institutes of Health Stroke Scale, lower blood pressure, and no large vessel occlusion were associated with both tissue-defined averted stroke and stroke with early symptom resolution. INTERPRETATION: In optimized stroke systems, 1 in 4 patients treated with thrombolysis recovered within 24 hours and 1 in 6 had no demonstrable brain injury on imaging. ANN NEUROL 2024;95:347-361.

Performance of Thrombectomy-Capable, Comprehensive, and Primary Stroke Centers in Reperfusion Therapies for Acute Ischemic Stroke: Report From the Get With The Guidelines-Stroke Registry.

BACKGROUND: The thrombectomy-capable stroke center (TSC) is a recently introduced intermediate tier of accreditation for hospitals at which patients with acute ischemic stroke receive care. The comparative quality and clinical outcomes of reperfusion therapies at TSCs, primary stroke centers (PSCs), and comprehensive stroke centers (CSCs) have not been well delineated. METHODS: We conducted a retrospective, observational, cohort study from 2018 to 2020 that included patients with acute ischemic stroke who received endovascular thrombectomy (EVT) and intravenous thrombolysis reperfusion therapies at CSCs, TSCs, or PSCs. Participants were recruited from Get With The Guidelines-Stroke registry. Study end points included timeliness of intravenous thrombolysis and EVT, successful reperfusion, discharge destination, discharge mortality, and functional independence at discharge. RESULTS: Among 84 903 patients, 48 682 received EVT, of whom 73% were treated at CSCs, 22% at PSCs, and 4% at TSCs. The median annual EVT volume was 76 for CSCs, 55 for TSCs, and 32 for PSCs. Patient differences by center status included higher National Institutes of Health Stroke Scale score, longer onset-to-arrival time, and higher transfer-in rates for CSCs, TSCs, and PSCs, respectively. In adjusted analyses, the likelihood of achieving the goal door-to-needle time was higher in CSCs compared with PSCs (odds ratio [OR], 1.39 [95% CI, 1.17-1.66]) and in TSCs compared with PSCs (OR, 1.45 [95% CI, 1.08-1.96]). Likewise, the odds of achieving the goal door-to-puncture time were higher in CSCs compared with PSCs (OR, 1.58 [95% CI, 1.13-2.21]). CSCs and TSCs also demonstrated better clinical efficacy outcomes compared with PSCs. The odds of discharge to home or rehabilitation were higher in CSCs compared with PSCs (OR, 1.18 [95% CI, 1.06-1.31]), whereas the odds of in-hospital mortality or discharge to hospice were lower in both CSCs compared with PSCs (OR, 0.87 [95% CI, 0.81-0.94]) and TSCs compared with PSCs (OR, 0.86 [95% CI, 0.75-0.98]). There were no significant differences in any of the quality-of-care metrics and clinical outcomes between TSCs and CSCs. CONCLUSIONS: In this study representing national US practice, CSCs and TSCs exceeded PSCs in key quality-of-care reperfusion metrics and outcomes, whereas TSCs and CSCs demonstrated a similar performance. With more than one-fifth of all EVT procedures during the study period conducted at PSCs, it may be desirable to explore national initiatives aimed at facilitating the elevation of eligible PSCs to a higher certification status.

Shorter Door-to-Needle Times Are Associated With Better Outcomes After Intravenous Thrombolytic Therapy and Endovascular Thrombectomy for Acute Ischemic Stroke.

BACKGROUND: Existing data and clinical trials could not determine whether faster intravenous thrombolytic therapy (IVT) translates into better long-term functional outcomes after acute ischemic stroke among those treated with endovascular thrombectomy (EVT). Patient-level national data can provide the required large population to study the associations between earlier IVT, versus later, with longitudinal functional outcomes and mortality in patients receiving IVT+EVT combined treatment. METHODS: This cohort study included older US patients (age ≥65 years) who received IVT within 4.5 hours or EVT within 7 hours after acute ischemic stroke using the linked 2015 to 2018 Get With The Guidelines-Stroke and Medicare database (38 913 treated with IVT only and 3946 with IVT+EVT). Primary outcome was home time, a patient-prioritized functional outcome. Secondary outcomes included all-cause mortality in 1 year. Multivariate logistic regression and Cox proportional hazards models were used to evaluate the associations between door-to-needle (DTN) times and outcomes. RESULTS: Among patients treated with IVT+EVT, after adjusting for patient and hospital factors, including onset-to-EVT times, each 15-minute increase in DTN times for IVT was associated with significantly higher odds of zero home time in a year (never discharged to home) (adjusted odds ratio, 1.12 [95% CI, 1.06-1.19]), less home time among those discharged to home (adjusted odds ratio, 0.93 per 1% of 365 days [95% CI, 0.89-0.98]), and higher all-cause mortality (adjusted hazard ratio, 1.07 [95% CI, 1.02-1.11]). These associations were also statistically significant among patients treated with IVT but at a modest degree (adjusted odds ratio, 1.04 for zero home time, 0.96 per 1% home time for those discharged to home, and adjusted hazard ratio 1.03 for mortality). In the secondary analysis where the IVT+EVT group was compared with 3704 patients treated with EVT only, shorter DTN times (≤60, 45, and 30 minutes) achieved incrementally more home time in a year, and more modified Rankin Scale 0 to 2 at discharge (22.3%, 23.4%, and 25.0%, respectively) versus EVT only (16.4%, P<0.001 for each). The benefit dissipated with DTN>60 minutes. CONCLUSIONS: Among older patients with stroke treated with either IVT only or IVT+EVT, shorter DTN times are associated with better long-term functional outcomes and lower mortality. These findings support further efforts to accelerate thrombolytic administration in all eligible patients, including EVT candidates.

Mechanical Thrombectomy Global Access For Stroke (MT-GLASS): A Mission Thrombectomy (MT-2020 Plus) Study.

BACKGROUND: Despite the well-established potent benefit of mechanical thrombectomy (MT) for large vessel occlusion (LVO) stroke, access to MT has not been studied globally. We conducted a worldwide survey of countries on 6 continents to define MT access (MTA), the disparities in MTA, and its determinants on a global scale. METHODS: Our survey was conducted in 75 countries through the Mission Thrombectomy 2020+ global network between November 22, 2020, and February 28, 2021. The primary end points were the current annual MTA, MT operator availability, and MT center availability. MTA was defined as the estimated proportion of patients with LVO receiving MT in a given region annually. The availability metrics were defined as ([current MT operators×50/current annual number of estimated thrombectomy-eligible LVOs]×100 = MT operator availability) and ([current MT centers×150/current annual number of estimated thrombectomy-eligible LVOs]×100= MT center availability). The metrics used optimal MT volume per operator as 50 and an optimal MT volume per center as 150. Multivariable-adjusted generalized linear models were used to evaluate factors associated with MTA. RESULTS: We received 887 responses from 67 countries. The median global MTA was 2.79% (interquartile range, 0.70-11.74). MTA was <1.0% for 18 (27%) countries and 0 for 7 (10%) countries. There was a 460-fold disparity between the highest and lowest nonzero MTA regions and low-income countries had 88% lower MTA compared with high-income countries. The global MT operator availability was 16.5% of optimal and the MT center availability was 20.8% of optimal. On multivariable regression, country income level (low or lower-middle versus high: odds ratio, 0.08 [95% CI, 0.04-0.12]), MT operator availability (odds ratio, 3.35 [95% CI, 2.07-5.42]), MT center availability (odds ratio, 2.86 [95% CI, 1.84-4.48]), and presence of prehospital acute stroke bypass protocol (odds ratio, 4.00 [95% CI, 1.70-9.42]) were significantly associated with increased odds of MTA. CONCLUSIONS: Access to MT on a global level is extremely low, with enormous disparities between countries by income level. The significant determinants of MT access are the country's per capita gross national income, prehospital LVO triage policy, and MT operator and center availability.

Statin Overuse in Cerebral Ischemia Without Indications: Systematic Review and Annual US Burden of Adverse Events.

BACKGROUND: Statin agents play a major role in secondary prevention after acute cerebral ischemia (ACI) events but are not indicated in all patients with ischemic stroke and transient ischemic attack. National guidelines recommend statins for patients with ACI of large or small vessel atherosclerotic origin and without these stroke mechanisms but coexisting coronary artery disease or primary prevention indications. The potential adverse effect burden of statin overuse in the remaining ACI patients have not been well delineated. METHODS: Per Preferred Reporting Items of Systematic Reviews and Meta-Analyses guidelines, we performed systematic meta-analyses of: (1) statin randomized clinical trials to determine absolute risk increases for 6 major adverse events; (2) large clinical series to determine the proportion of ACI events due to large or small vessel atherosclerotic disease; and (3) the proportion of remaining patients with coronary artery disease/primary prevention statin indications. RESULTS: For adverse effects, data were available from 63 randomized clinical trials enrolling 155 107 patients. Statin therapy was associated with an increased risk of the occurrence of 6 conditions: diabetes, myalgia or muscle weakness, myopathy, liver disease, renal insufficiency, and eye disease. Across 55 large series enrolling 53 501 patients, the rate of ACI due to large and small artery atherosclerosis was 45.0% (large artery atherosclerosis 21.6%, small vessel disease 23.4%), the rate of remaining patients with coronary artery disease/primary prevention statin indications was 31.8%, and the rate of patients without statin indications was 23.2%. Data synthesis indicated that, in the United States, were all patients with ACI without statin indications treated with statins, a total of 5601 patients would develop needless adverse events each year, most commonly diabetes, myopathy, and eye disease. CONCLUSIONS: More than one-fifth of patients with ACI do not have an indication for statins, and statin overuse in these patients could annually lead to over 5600 adverse events each year in the United States, including diabetes, myopathy, and eye disease. These findings emphasize the importance of adhering to guideline indications for the start of statin therapy in ACI.

Subarachnoid Hemorrhage Trials: Cutting, Sliding, or Keeping mRS Scores and WFNS Grades.

Rigorous evidence generation with randomized controlled trials has lagged for aneurysmal subarachnoid hemorrhage (SAH) compared with other forms of acute stroke. Besides its lower incidence compared with other stroke subtypes, the presentation and outcome of patients with SAH also differ. This must be considered and adjusted for in designing pivotal randomized controlled trials of patients with SAH. Here, we show the effect of the unique expected distribution of the SAH severity at presentation (World Federation of Neurological Surgeons grade) on the outcome most used in pivotal stroke randomized controlled trials (modified Rankin Scale) and, consequently, on the sample size. Furthermore, we discuss the advantages and disadvantages of different options to analyze the outcome and control the expected distribution of the World Federation of Neurological Surgeons grades in addition to showing their effects on the sample size. Finally, we offer methods that investigators can adapt to more precisely understand the effect of common modified Rankin Scale analysis methods and trial eligibility pertaining to the World Federation of Neurological Surgeons grade in designing their large-scale SAH randomized controlled trials.

Patent Foramen Ovale Management for Secondary Stroke Prevention: State-of-the-Art Appraisal of Current Evidence.

Patent foramen ovale (PFO) is frequently identified in young patients with ischemic stroke. Randomized controlled trials provide robust evidence supporting PFO closure in selected patients with cryptogenic ischemic stroke; however, several questions remain unanswered. This report summarizes current knowledge on the epidemiology of PFO-associated stroke, the role of PFO as a cause of stroke, and anatomic high-risk features. We also comment on breakthrough developments in patient selection algorithms for PFO closure in relation to the PFO-associated stroke causal likelihood risk stratification system. We further highlight areas for future research in PFO-associated stroke including the efficacy and safety of PFO closure in the elderly population, incidence, and long-term consequences of atrial fibrillation post-PFO closure, generalizability of the results of clinical trials in the real world, and the need for assessing the effect of neurocardiology teams on adherence to international recommendations. Other important knowledge gaps such as sex, race/ethnicity, and regional disparities in access to diagnostic technologies, PFO closure devices, and clinical outcomes in the real world are also discussed as priority research topics.

Magnesium and Hematoma Expansion in Intracerebral Hemorrhage: A FAST-MAG Randomized Trial Analysis.

BACKGROUND: Observational studies suggest that magnesium may have hemostatic effects. FAST-MAG (Field Administration of Stroke Therapy-Magnesium) was a pragmatic clinical trial of magnesium sulfate administered prehospital for acute clinical stroke syndromes and included patients with intracerebral hemorrhage. Exploratory secondary analysis by the treatment group found no reduction in hematoma expansion (HE) associated with magnesium treatment in intracerebral hemorrhage but did not consider serum magnesium levels achieved. We analyzed FAST-MAG intracerebral hemorrhage data for associations between serum magnesium level, HE, and early neurological deterioration, accounting for groupwise biases. METHODS: HE was defined as hematoma volume increase ≥3 mL within 24 hours and early neurological deterioration as ≥1-point Glasgow Coma Scale decline from arrival to hospital day 4. Comparing treatment and placebo groups confirmed biased availability of neuroimaging data. Therefore, HE and neurological deterioration were analyzed and stratified by treatment and placebo groups using univariate tests and adjusted logistic regression. RESULTS: Spontaneous intracerebral hemorrhage was present in 381 patients. Placebo patients had fewer serial neuroimaging studies available (123 [65.4%] versus 145 [75.1%]; P=0.038). Necessary data were available in 104 magnesium- and 85 placebo-treated patients (age, 64.9 [13.0] years; 67.7% male). In the magnesium group, higher magnesium level was associated with less HE (adjusted odds ratio, 0.64 per mg/dL [95% CI, 0.42-0.93]) and less neurological deterioration (adjusted odds ratio, 0.54 per mg/dL [95% CI, 0.33-0.82]). In the placebo group, magnesium level was not associated with either HE or neurological deterioration. CONCLUSIONS: Magnesium may exhibit a hemostatic effect that was only observable in the FAST-MAG magnesium treatment group. Equipoise should be maintained, and specific trials are needed. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT00059332.

Twenty Years of Sustained Improvement in Quality of Care and Outcomes for Patients Hospitalized With Stroke or Transient Ischemic Attack: Data From The Get With The Guidelines-Stroke Program.

BACKGROUND: The Get With The Guidelines-Stroke program is a quality improvement initiative designed to enhance adherence to evidence-based stroke care. Since its inception in 2003, over 2800 hospitals in the United States have participated in the program. METHODS: We examined patient characteristics, adherence to performance measures, and in-hospital outcomes in patients hospitalized for acute ischemic stroke, subarachnoid hemorrhage, intracerebral hemorrhage, and transient ischemic attack in The Get With The Guidelines-Stroke hospitals from 2003 through 2022. We quantified temporal changes in performance measure adherence and clinical outcomes over time. Performance measure denominators consisted of patients who were eligible, excluding those with contraindications. RESULTS: Over the 20 years of the program, a total of 7837 849 stroke cases (median age 71 years, 51.0% female; 69.2% ischemic strokes, 3.9% SAHs, 11.5% ICHs, and 15.3% TIAs) were entered into the registry. Except for antithrombotics at discharge, in which the baseline performance was >92%, there was sustained improvement in all performance metrics regardless of type of cerebrovascular event (P<0.01 for all). In patients with acute ischemic stroke, large improvements were observed for anticoagulation for atrial fibrillation (55.7% in 2003 to 97.2% in 2022), smoking cessation counseling (44.7%-97.8%), dysphagia screening (53.8%-83.5%), thrombolytic treatment for patients arriving by 3.5 hours, treat by 4.5 hours (15.2%-92.9%), door-to-needle time within 60 minutes (19.0%-75.3%), and endovascular door-to-puncture time within 90 minutes (54.7%-62.8%). Similar improvements were also observed for measures relevant to patients with subarachnoid hemorrhage, intracerebral hemorrhage, and transient ischemic attack. Multivariable analysis showed that there was a sustained increase in odds of receiving each performance measure over time, independent of patient and hospital characteristics for each type of cerebrovascular event. After risk adjustment, there were temporal trends that patients were less likely to be discharged to a skilled nursing facility, and, for ischemic stroke only, more likely to be discharged directly home. CONCLUSIONS: During the first 20 years, Get With The Guidelines-Stroke participation was associated with sustained improvement in evidence-based care and outcomes for patients with stroke and transient ischemic attack in the United States.

HERMES-24 Score Derivation and Validation for Simple and Robust Outcome Prediction After Large Vessel Occlusion Treatment.

BACKGROUND: Clinicians need simple and highly predictive prognostic scores to assist practical decision-making. We aimed to develop a simple outcome prediction score applied 24 hours after anterior circulation acute ischemic stroke treatment with endovascular thrombectomy and validate it in patients treated both with and without endovascular thrombectomy. METHODS: Using the HERMES (Highly Effective Reperfusion Evaluated in Multiple Endovascular Stroke Trials) collaboration data set (n=1764), patients in the endovascular thrombectomy arm were divided randomly into a derivation cohort (n=430) and a validation cohort (n=441). From a set of candidate predictors, logistic regression modeling using forward variable selection was used to select a model that was both parsimonious and highly predictive for modified Rankin Scale (mRS) ≤2 at 90 days. The score was validated in validation cohort, control arm (n=893), and external validation cohorts from the ESCAPE-NA1 (Efficacy and Safety of Nerinetide for the Treatment of Acute Ischaemic Stroke; n=1066) and INTERRSeCT (Identifying New Approaches to Optimize Thrombus Characterization for Predicting Early Recanalization and Reperfusion With IV Alteplase and Other Treatments Using Serial CT Angiography; n=614). RESULTS: In the derivation cohort, we selected 2 significant predictors of mRS ≤2 (National Institutes of Health Stroke Scale score at 24 hours and age [ß-coefficient, 0.34 and 0.06]) and derived the HERMES-24 score: age (years)/10+National Institutes of Health Stroke Scale score at 24 hours. The HERMES-24 score was highly predictive for mRS ≤2 (c-statistic 0.907 [95% CI, 0.879-0.935]) in the derivation cohort. In the validation cohort and the control arm, the HERMES-24 score predicts mRS ≤2 (c-statistic, 0.914 [95% CI, 0.886-0.944] and 0.909 [95% CI, 0.887-0.930]). Observed provability of mRS ≤2 ranged between 3.1% and 3.4% when HERMES-24 score ≥25, while it ranged between 90.6% and 93.0% when HERMES-24 score <10 in the derivation cohort, validation cohort, and control arm. The HERMES-24 score also showed c-statistics of 0.894 and 0.889 for mRS ≤2 in the ESCAPE-NA1 and INTERRSeCT populations. CONCLUSIONS: The post-treatment HERMES-24 score is a simple validated score that predicts a 3-month outcome after anterior circulation large vessel occlusion stroke regardless of intervention, which helps prognostic discussion with families on day 2.

Mapping the Ecological Terrain of Stroke Prehospital Delay: A Nationwide Registry Study.

BACKGROUND: Delays in hospital presentation limit access to acute stroke treatments. While prior research has focused on patient-level factors, broader ecological and social determinants have not been well studied. We aimed to create a geospatial map of prehospital delay and examine the role of community-level social vulnerability. METHODS: We studied patients with ischemic stroke who arrived by emergency medical services in 2015 to 2017 from the American Heart Association Get With The Guidelines-Stroke registry. The primary outcome was time to hospital arrival after stroke (in minutes), beginning at last known well in most cases. Using Geographic Information System mapping, we displayed the geography of delay. We then used Cox proportional hazard models to study the relationship between community-level factors and arrival time (adjusted hazard ratios [aHR] <1.0 indicate delay). The primary exposure was the social vulnerability index (SVI), a metric of social vulnerability for every ZIP Code Tabulation Area ranging from 0.0 to 1.0. RESULTS: Of 750 336 patients, 149 145 met inclusion criteria. The mean age was 73 years, and 51% were female. The median time to hospital arrival was 140 minutes (Q1: 60 minutes, Q3: 458 minutes). The geospatial map revealed that many zones of delay overlapped with socially vulnerable areas (https://harvard-cga.maps.arcgis.com/apps/webappviewer/index.html?id=08f6e885c71b457f83cefc71013bcaa7). Cox models (aHR, 95% CI) confirmed that higher SVI, including quartiles 3 (aHR, 0.96 [95% CI, 0.93-0.98]) and 4 (aHR, 0.93 [95% CI, 0.91-0.95]), was associated with delay. Patients from SVI quartile 4 neighborhoods arrived 15.6 minutes [15-16.2] slower than patients from SVI quartile 1. Specific SVI themes associated with delay were a community's socioeconomic status (aHR, 0.80 [95% CI, 0.74-0.85]) and housing type and transportation (aHR, 0.89 [95% CI, 0.84-0.94]). CONCLUSIONS: This map of acute stroke presentation times shows areas with a high incidence of delay. Increased social vulnerability characterizes these areas. Such places should be systematically targeted to improve population-level stroke presentation times.

What Is a Meaningful Difference When Using Infarct Volume as the Primary Outcome?: Results From the HERMES Database.

BACKGROUND: Ischemic stroke lesion volume at follow-up is an important surrogate outcome for acute stroke trials. We aimed to assess which differences in 48-hour lesion volume translate into meaningful clinical differences. METHODS: We used pooled data from 7 trials investigating the efficacy of endovascular treatment for anterior circulation large vessel occlusion in acute ischemic stroke. We assessed 48-hour lesion volume follow-up computed tomography or magnetic resonance imaging. The primary outcome was a good functional outcome, defined as modified Rankin Scale (mRS) scores of 0 to 2. We performed multivariable logistic regression to predict the probability of achieving mRS scores of 0 to 2 and determined the differences in 48-hour lesion volume that correspond to a change of 1%, 5%, and 10% in the adjusted probability of achieving mRS scores of 0 to 2. RESULTS: In total, 1665/1766 (94.2%) patients (median age, 68 [interquartile range, 57-76] years, 781 [46.9%] female) had information on follow-up ischemic lesion volume. Computed tomography was used for follow-up imaging in 83% of patients. The median 48-hour lesion volume was 41 (interquartile range, 14-120) mL. We observed a linear relationship between 48-hour lesion volume and mRS scores of 0 to 2 for adjusted probabilities between 65% and 20%/volumes <80 mL, although the curve sloped off for lower mRS scores of 0-2 probabilities/higher volumes. The median differences in 48-hour lesion volume associated with a 1%, 5%, and 10% increase in the probability of mRS scores of 0 to 2 for volumes <80 mL were 2 (interquartile range, 2-3), 10 (9-11), and 20 (18-23) mL, respectively. We found comparable associations when assessing computed tomography and magnetic resonance imaging separately. CONCLUSIONS: A difference of 2, 10, and 20 mL in 48-hour lesion volume, respectively, is associated with a 1%, 5%, and 10% absolute increase in the probability of achieving good functional outcome. These results can inform the design of future stroke trials that use 48-hour lesion volume as the primary outcome.

Intravenous Tirofiban Versus Alteplase Before Endovascular Treatment in Acute Ischemic Stroke: A Pooled Analysis of the DEVT and RESCUE BT Trials.

BACKGROUND: The present study aimed to evaluate the efficacy and safety of intravenous tirofiban versus alteplase before endovascular treatment (EVT) in acute ischemic stroke patients with intracranial large vessel occlusion. METHODS: This was a post hoc analysis using data from 2 multicenter, randomized trials: the DEVT trial (Direct Endovascular Treatment for Large Vessel Occlusion Stroke) from May 2018 to May 2020 and the RESCUE BT trial (Intravenous Tirofiban Before Endovascular Thrombectomy for Acute Ischemic Stroke) from October 2018 to October 2021. Patients with acute intracranial large vessel occlusion within 4.5 hours from last known well were dichotomized into 2 groups: tirofiban plus EVT versus alteplase bridging with EVT. The primary outcome was functional independence (modified Rankin Scale score of 0-2) at 90 days. Safety outcomes included symptomatic intracranial hemorrhage and 3-month mortality. Multivariable logistic regression (adjusting for baseline systolic blood pressure, occlusion site, onset-to-puncture time, anesthesia, and first choice of EVT) and propensity score overlap weighting (balance in demographic covariates, stroke characteristics, and initial management between groups) were performed. RESULTS: One-hundred and eighteen alteplase-treated patients in the DEVT trial and 98 tirofiban-treated patients in the RESCUE BT trial were included (median age, 70 years; 115 [53.2%] men). The rate of functional independence was 60.2% in the tirofiban group compared with 46.6% in the alteplase group (adjusted odds ratio, 1.25 [95% CI, 0.60-2.63]). Compared with alteplase, tirofiban was not associated with increased risk of symptomatic intracranial hemorrhage (6.8% versus 9.2%; P=0.51) and mortality (17.8% versus 19.4%; P=0.76). The propensity score overlap weighting analyses showed consistent outcomes. CONCLUSIONS: Among patients with intracranial large vessel occlusion within 4.5 hours of onset, tirofiban plus EVT was comparable to alteplase bridging with EVT regarding the efficacy and safety outcomes. These findings should be interpreted as preliminary and require confirmation in a randomized trial. REGISTRATION: URL: https://www.chictr.org.cn; Unique identifiers: ChiCTR-IOR-17013568 and ChiCTR-INR-17014167.

Influence of Time to Achieve Target Systolic Blood Pressure on Outcome After Intracerebral Hemorrhage: The Blood Pressure in Acute Stroke Collaboration.

OBJECTIVE: To investigate whether an earlier time to achieving and maintaining systolic blood pressure (SBP) at 120 to 140 mm Hg is associated with favorable outcomes in a cohort of patients with acute intracerebral hemorrhage. METHODS: We pooled individual patient data from randomized controlled trials registered in the Blood Pressure in Acute Stroke Collaboration. Time was defined as time form symptom onset plus the time (hour) to first achieve and subsequently maintain SBP at 120 to 140 mm Hg over 24 hours. The primary outcome was functional status measured by the modified Rankin Scale at 90 to 180 days. A generalized linear mixed models was used, with adjustment for covariables and trial as a random effect. RESULTS: A total of 5761 patients (mean age, 64.0 [SD, 13.0], 2120 [36.8%] females) were included in analyses. Earlier SBP control was associated with better functional outcomes (modified Rankin Scale score, 3-6; odds ratio, 0.98 [95% CI, 0.97-0.99]) and a significant lower risk of hematoma expansion (0.98, 0.96-1.00). This association was stronger in patients with bigger baseline hematoma volume (>10 mL) compared with those with baseline hematoma volume ≤10 mL (0.006 for interaction). Earlier SBP control was not associated with cardiac or renal adverse events. CONCLUSIONS: Our study confirms a clear time relation between early versus later SBP control (120-140 mm Hg) and outcomes in the one-third of patients with intracerebral hemorrhage who attained sustained SBP levels within this range. These data provide further support for the value of early recognition, rapid transport, and prompt initiation of treatment of patients with intracerebral hemorrhage.

Mechanical Thrombectomy Access Score: A Systematic Review and Modified Delphi of Global Barriers to Endovascular Therapy.

BACKGROUND: The availability of mechanical thrombectomy (MT) for acute ischemic stroke is limited, and vast disparities exist between countries. We aim to create a MT access score to measure the drivers of access to help quantify and accelerate treatment worldwide. METHODS: We used a systematic review complemented by a modified Delphi method. In the first of 3 rounds, 4 independent investigators performed a systematic literature review using key search terms that drive MT access, following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. In the second round, a panel of 6 anonymous international experts selected key attributes needed for scoring. In the final round, a total of 12 attributes were selected on consensus, each given a score on a 0 to 3 scale. An ultimate MT access score (range, 0-36) was proposed as a new tool to use in identifying barriers to MT access and assist in providing an initial framework for public health interventions. RESULTS: Of 2864 abstracts screened, 121 studies were included in the final systematic review. A total of 34 attributes that potentially drive MT access were initially identified. In the final round, 12 attributes were selected by the expert panel: public awareness, emergency medical services transportation, prehospital large vessel occlusion screening, interhospital transfer policy, emergency department protocols, stroke imaging protocols, emergency department stroke expertise or telestroke availability, interventionalists, MT-capable centers, device availability, and insurance coverage. These attributes were weighted as part of the final score of 0 to 36. CONCLUSIONS: The MT access score represents the first tool to quantify barriers to global MT access. Its implementation stands not just as an academic achievement but as a beacon of hope for improving stroke care and outcomes worldwide, bringing us a step closer to bridging the gap in stroke treatment disparities.

Prospective, Multicenter, Controlled Trial of Mobile Stroke Units.

BACKGROUND: Mobile stroke units (MSUs) are ambulances with staff and a computed tomographic scanner that may enable faster treatment with tissue plasminogen activator (t-PA) than standard management by emergency medical services (EMS). Whether and how much MSUs alter outcomes has not been extensively studied. METHODS: In an observational, prospective, multicenter, alternating-week trial, we assessed outcomes from MSU or EMS management within 4.5 hours after onset of acute stroke symptoms. The primary outcome was the score on the utility-weighted modified Rankin scale (range, 0 to 1, with higher scores indicating better outcomes according to a patient value system, derived from scores on the modified Rankin scale of 0 to 6, with higher scores indicating more disability). The main analysis involved dichotomized scores on the utility-weighted modified Rankin scale (≥0.91 or <0.91, approximating scores on the modified Rankin scale of ≤1 or >1) at 90 days in patients eligible for t-PA. Analyses were also performed in all enrolled patients. RESULTS: We enrolled 1515 patients, of whom 1047 were eligible to receive t-PA; 617 received care by MSU and 430 by EMS. The median time from onset of stroke to administration of t-PA was 72 minutes in the MSU group and 108 minutes in the EMS group. Of patients eligible for t-PA, 97.1% in the MSU group received t-PA, as compared with 79.5% in the EMS group. The mean score on the utility-weighted modified Rankin scale at 90 days in patients eligible for t-PA was 0.72 in the MSU group and 0.66 in the EMS group (adjusted odds ratio for a score of ≥0.91, 2.43; 95% confidence interval [CI], 1.75 to 3.36; P<0.001). Among the patients eligible for t-PA, 55.0% in the MSU group and 44.4% in the EMS group had a score of 0 or 1 on the modified Rankin scale at 90 days. Among all enrolled patients, the mean score on the utility-weighted modified Rankin scale at discharge was 0.57 in the MSU group and 0.51 in the EMS group (adjusted odds ratio for a score of ≥0.91, 1.82; 95% CI, 1.39 to 2.37; P<0.001). Secondary clinical outcomes generally favored MSUs. Mortality at 90 days was 8.9% in the MSU group and 11.9% in the EMS group. CONCLUSIONS: In patients with acute stroke who were eligible for t-PA, utility-weighted disability outcomes at 90 days were better with MSUs than with EMS. (Funded by the Patient-Centered Outcomes Research Institute; BEST-MSU ClinicalTrials.gov number, NCT02190500.).

MRI in the Evaluation of Cryptogenic Stroke and Embolic Stroke of Undetermined Source.

Cryptogenic stroke refers to a stroke of undetermined etiology. It accounts for approximately one-fifth of ischemic strokes and has a higher prevalence in younger patients. Embolic stroke of undetermined source (ESUS) refers to a subgroup of patients with nonlacunar cryptogenic strokes in whom embolism is the suspected stroke mechanism. Under the classifications of cryptogenic stroke or ESUS, there is wide heterogeneity in possible stroke mechanisms. In the absence of a confirmed stroke etiology, there is no established treatment for secondary prevention of stroke in patients experiencing cryptogenic stroke or ESUS, despite several clinical trials, leaving physicians with a clinical dilemma. Both conventional and advanced MRI techniques are available in clinical practice to identify differentiating features and stroke patterns and to determine or infer the underlying etiologic cause, such as atherosclerotic plaques and cardiogenic or paradoxical embolism due to occult pelvic venous thrombi. The aim of this review is to highlight the diagnostic utility of various MRI techniques in patients with cryptogenic stroke or ESUS. Future trends in technological advancement for promoting the adoption of MRI in such a special clinical application are also discussed.