Prospective, Multicenter, Controlled Trial of Mobile Stroke Units

Transforming Early Stroke Care Through Mobile Stroke Treatment Unit Rendezvous With Rural Emergency Medical Services

BACKGROUND

Mobile stroke units, also sometimes called Mobile Stroke Treatment Units (MSTUs) are changing the paradigm of acute stroke care and are considered to be an extension of the time is brain concept. Of the <20 active Mobile Stroke Programs in the United States, most are rooted in urban settings. In July 2023, the first MSTU in Florida was launched in Alachua County, implementing a unique and innovative rendezvous process with rural emergency medical services (EMS). We compared stroke outcome metrics between the MSTU, including rendezvous patients, and the standard process of EMS to the emergency department (ED).

METHODS

We performed a retrospective analysis of patients with acute stroke evaluated in the MSTU and those transported to the ED by the standard EMS stroke alert process at an academic Comprehensive Stroke Center between July 25, 2023 and May 31, 2024. Patient demographic and acute stroke metrics were extracted to complete univariate and multivariate logistic regression analysis.

RESULTS

Across all 3 groups, both MSTU patients with (n=76) and without (n=291) rendezvous compared with EMS-to-ED patients (n=807), had significantly shorter mean dispatch-to-door times (29.4 versus 28.5 versus 73.2 minutes, respectively; P<0.01), dispatch-to-needle times (41.3 versus 44.6 versus 104.1 minutes, respectively; P<0.01), and dispatch-to-puncture (92.7 versus 81.9 versus 138.0 minutes, respectively; P<0.01). In rural counties, MSTU rendezvous patients (n=76) compared with EMS-to-ED patients (n=206), had shorter mean dispatch-to-door and dispatch-to-needle times (41.3 versus 97.8 minutes, respectively; P<0.001). After adjusting for age and sex, these differences remained significant (odds ratio, 1.21 [95% CI, 1.07-1.37]; P<0.01 and odds ratio, 1.80 [95% CI, 1.07-3.04]; P=0.03, respectively).

CONCLUSIONS

Our study demonstrates the effectiveness of MSTUs in Florida and establishes that the MSTU rendezvous process significantly improves timely stroke care in underserved rural counties.

Prehospital blood pressure lowering in patients with ischemic stroke: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Whether prehospital blood pressure control improves outcomes among patients with acute ischemic stroke is uncertain. This systematic review and meta-analysis aimed to evaluate the effect of prehospital blood pressure reduction treatment in patients with ischemic stroke.

METHODS

We searched PubMed, Embase, and the Cochrane Central Register of Controlled Trials for randomized controlled trials that compared prehospital blood pressure reduction treatment with usual treatment or no treatment in patients with stroke. The primary outcome was functional outcome, assessed with the distribution of modified Rankin Scale (mRS) at 90 days, while secondary outcome was mortality at 90 days.

RESULTS

Of 428 studies reviewed, three were appropriate for analysis, totaling 3878 patients. In patients with ischemic stroke, prehospital blood pressure reduction treatment was associated with higher mRS scores at 90 days (common odds ratio (OR) for worse mRS, OR: 1.27, 95% confidence interval (CI): 1.08-1.49) and increased risk of mortality at 90 days (OR: 1.28, 95% CI: 1.02-1.61) compared with the usual treatment.

CONCLUSION

In patients with ischemic stroke, prehospital blood pressure reduction treatment was associated with a higher likelihood of poor functional outcome and an elevated risk of mortality.

2025 Heart Disease and Stroke Statistics: A Report of US and Global Data From the American Heart Association

BACKGROUND

The American Heart Association (AHA), in conjunction with the National Institutes of Health, annually reports the most up-to-date statistics related to heart disease, stroke, and cardiovascular risk factors, including core health behaviors (smoking, physical activity, nutrition, sleep, and obesity) and health factors (cholesterol, blood pressure, glucose control, and metabolic syndrome) that contribute to cardiovascular health. The AHA Heart Disease and Stroke Statistical Update presents the latest data on a range of major clinical heart and circulatory disease conditions (including stroke, brain health, complications of pregnancy, kidney disease, congenital heart disease, rhythm disorders, sudden cardiac arrest, subclinical atherosclerosis, coronary heart disease, cardiomyopathy, heart failure, valvular disease, venous thromboembolism, and peripheral artery disease) and the associated outcomes (including quality of care, procedures, and economic costs).

METHODS

The AHA, through its Epidemiology and Prevention Statistics Committee, continuously monitors and evaluates sources of data on heart disease and stroke in the United States and globally to provide the most current information available in the annual Statistical Update with review of published literature through the year before writing. The 2025 AHA Statistical Update is the product of a full year's worth of effort in 2024 by dedicated volunteer clinicians and scientists, committed government professionals, and AHA staff members. This year's edition includes a continued focus on health equity across several key domains and enhanced global data that reflect improved methods and incorporation of ≈3000 new data sources since last year's Statistical Update.

RESULTS

Each of the chapters in the Statistical Update focuses on a different topic related to heart disease and stroke statistics.

CONCLUSIONS

The Statistical Update represents a critical resource for the lay public, policymakers, media professionals, clinicians, health care administrators, researchers, health advocates, and others seeking the best available data on these factors and conditions.

Efficacy and safety of intravenous nerinetide initiated by paramedics in the field for acute cerebral ischaemia within 3 h of symptom onset (FRONTIER): a phase 2, multicentre, randomised, double-blind, placebo-controlled study

BACKGROUND

Nerinetide is a neuroprotectant effective in preclinical models of acute ischaemic stroke when administered within 3 h of onset. However, the clinical evaluation of neuroprotectants in this short timeframe is challenging. We sought to establish the feasibility, safety, and effectiveness of nerinetide when given before hospital arrival within 3 h of symptom onset of suspected stroke.

METHODS

In this multicentre, randomised, double-blind, placebo-controlled study, paramedics enrolled participants aged 40-95 years within 3 h of suspected severe stroke onset, who were previously independent, and were being taken to one of seven stroke centres in Ontario or British Columbia, Canada. The primary hypothesis was that the administration of nerinetide would result in a higher rate of good functional outcomes. Participants were randomly assigned 1:1 to intravenous nerinetide (2·6 mg/kg) or placebo, each in visually identical vials. Paramedics, hospital care providers, and outcome evaluators were masked to treatment assignment. The primary outcome was good functional outcome on a sliding dichotomy of the modified Rankin Scale at 90 days. Participants were assessed on day 4, 30, and 90 by the stroke center research team, in person or over the telephone. Outcomes, adjusted for age and stroke severity, were evaluated in the modified intention-to-treat (mITT) population, and in the target population of those with acute ischaemic stroke. The safety population included all participants who received the study drug. This study is registered with ClinicalTrials.gov (NCT02315443), and trial enrolment has concluded.

FINDINGS

Between March 26, 2015, and March 27, 2023, 532 participants received nerinetide (n=265) or placebo (n=267). The mITT population of suspected stroke (n=507; 254 nerinetide and 253 placebo) included 321 (63%) with acute ischaemic stroke, 93 (18%) with intracranial haemorrhage, 44 (9%) with transient ischaemic attack, and 49 (10%) with stroke-mimicking conditions. Treatment began a median of 64 min (IQR 47-100) from symptom onset. Participants randomly assigned to nerinetide had more severe strokes compared with those receiving placebo (median National Institutes of Health Stroke Scale (NIHSS) 12, IQR 5-19 vs 10, 4-18 in mITT, and 14, 7-19 vs 10, 4-18 in the acute ischaemic stroke subgroup). Overall, 145 (57%) of 254 participants in the nerinetide group and 147 (58%) of 253 in the placebo group had the primary outcome of a favourable functional outcome using the prespecified sliding dichotomy at 90 days (adjusted odds ratio 1·05, 95% CI 0·73-1·51; adjusted risk ratio 1·04, 95% CI 0·85-1·25). In the 302 patients with ischaemic stroke, the favourable functional outcome adjusted for arrival NIHSS and age favoured nerinetide (odds ratio 1·53, 0·93-2·52 and risk ratio 1·21, 0·97-1·52). In those given reperfusion therapies (thrombolysis or endovascular thrombectomy, or both) nerinetide was associated with improved favourable functional outcomes (adjusted odds ratio 1·84, 1·03-3·28; adjusted risk ratio 1·29, 1·01-1·65). There was no apparent benefit in haemorrhagic stroke or acute ischaemic stroke without reperfusion. There were no safety concerns.

INTERPRETATION

Prehospital nerinetide did not improve neurological functional outcomes in all patients with suspected ischaemic stroke in the mITT population. Nerinetide might benefit patients with acute ischaemic stroke who are selected for reperfusion therapies within 3 h of symptom onset. This finding should be confirmed in a future trial.

FUNDING

Brain Canada and NoNO.

Stroke-Related Factors Influencing Thrombolysis Eligibility and Outcomes

OBJECTIVE

Intravenous thrombolysis (IVT) improves outcomes of acute ischemic stroke (AIS) when timely administered. The aim of this study was to collect and analyze data of stroke-related factors which may influence the performance of stroke-related rescue chains, the use of IVT, and patients' outcomes.

METHODS

This study enrolled patients with AIS admitted to our Stroke Unit (SU) between January 1, 2023, and December 31, 2023. We investigated whether age, occurrence of baseline disabling deficits, stroke severity, or stroke location influenced the median Onset-to-Door Time (ODT), the chance of receiving IVT, or the outcomes of AIS in our facility.

RESULTS

A total of 208 patients were enrolled. Patients who received IVT had higher baseline National Institute of Health Stroke Scale (NIHSS) scores (12.26±1.2) than those who did not (6.77±0.51) (P<0.0001). Patients with IVT further showed a greater strength deficit, less ataxia, and lower median ODT (108±20 min) than patients with NO IVT (720±67) (P<0.0001). Weakness of the lower limbs and higher total NIHSS predicted ODT≤ 3.5 hours and the use of IVT. Ataxia and Posterior Circulation Stroke slowed the rescue chain and were negatively correlated with the use of IVT.

CONCLUSIONS

Stroke-related factors may slow the rescue chain and affect the application of IVT for AIS. New evaluation strategies are warranted to overcome the detrimental effects of these factors and to allow clinicians to effectively manage strokes of any severity and location.

A Prospective Multicenter Analysis of Mobile Stroke Unit Cost-Effectiveness

OBJECTIVE

Given the high disease and cost burden of ischemic stroke, evaluating the clinical efficacy and cost-effectiveness of new approaches to prevent and treat ischemic stroke is critical. Effective ischemic stroke management depends on timely administration of thrombolytics after stroke onset. This study evaluates the cost-effectiveness associated with the use of mobile stroke units (MSUs) to expedite tissue plasminogen activator (tPA) administration, as compared with standard management through emergency medical services (EMS).

METHODS

This study is a prospective, multicenter, alternating-week, cluster-controlled trial of MSU versus EMS. One-year and life-time cost-effectiveness analyses, using the incremental cost-effectiveness ratio (ICER) method, were performed from the perspective of CMS's Medicare. Quality-adjusted life years (QALYs) estimated using patient-reported EQ-5D-5L data were used as the effectiveness measure. Health care utilizations were converted to costs using average national Medicare reimbursements. ICERs excluding patients with pre-existing disability, and limited to stroke-related costs were also calculated.

RESULTS

The first-year ICER for all tPA-eligible patients using total cost differences between MSU and EMS groups was $238,873/QALY; for patients without pre-existing disability was $61,199/QALY. The lifetime ICERs for all tPA-eligible patients and for those without pre-existing disability were $94,710 and $31,259/QALY, respectively. All ICERs were lower when restricted to stroke-related costs and were highly dependent on the number of patients treated per year in an MSU.

INTERPRETATION

MSUs' cost-effectiveness is borderline if we consider total first-year costs and outcomes in all tPA-eligible patients. MSUs are cost-effective to highly cost-effective when calculations are based on patients without pre-existing disability, patients' lifetime horizon, stroke-related costs, and more patients treated per year in an MSU. ANN NEUROL 2025;97:209-221.

Prehospital technologies for early stroke detection - A review

The rate of neural circuitry loss in a typical large vessel occlusion well emphasizes that 'Time is Brain'. Every untreated minute in a large vessel ischaemic stroke results in loss of 1.9 million neurons and 13.8 billion synapses. As such, it is essential to optimize the flow-limiting steps in delivering the current standard of care. The current diagnostic model involves recognition of symptoms by patients, followed by access to Emergency Medical Services and subsequent physical examination and neuroimaging in the Emergency Department. With more than 50% of stroke patients using Emergency Medical Services as the first point of care contact, it can be deduced that the outcome of the 'stroke chain of survival' can be improved by addressing the bottleneck of prehospital stroke diagnosis. Here we present a review of the existing technologies.

Bridging thrombolysis with tenecteplase versus endovascular thrombectomy alone for large-vessel anterior circulation stroke: a target trial emulation analysis

BACKGROUND

Whether bridging thrombolysis with tenecteplase is beneficial compared with thrombectomy alone in patients who had a stroke with large-vessel occlusion remains unclear.

METHODS

This is a causal inference study of observational data from the trials SWIFT DIRECT and EXTEND-IA TNK Parts 1 and 2 applying target trial emulation. We compared patients receiving thrombectomy alone to patients receiving tenecteplase 0.25 mg/kg or 0.40 mg/kg before thrombectomy. The primary outcome was functional independence (modified Rankin Scale (mRS) of 0-2) at 90 days. Secondary outcomes included improvement over the full ordinal mRS scale, freedom of disability (mRS 0-1), mortality and occurrence of symptomatic intracranial haemorrhage. The average causal treatment effect was estimated via inverse probability of treatment weighting and G-Computation. We calculated standardised risk differences (SRDs) and adjusted (common) ORs (a(c)ORs).

RESULTS

Of 377 patients included in the target trial, 187 received thrombectomy alone and 190 tenecteplase before thrombectomy. Tenecteplase before thrombectomy did not increase the probability of patients achieving functional independence (SRD 0.04 (95% CI -0.06 to 0.13)) but resulted in a significant improvement in the mRS overall (acOR 1.56 (95% CI 1.07 to 2.23)) and in a higher probability of freedom from disability (SRD 0.10 (95% CI 0.01 to 0.20)). The probability for improvement of functional outcomes was further increased in patients treated within 140 min after onset (ordinal mRS acOR 1.63 (95% CI 1.04 to 2.56)). No significant differences in safety outcomes were observed between the two groups.

CONCLUSION

Tenecteplase before thrombectomy compared with thrombectomy alone did not increase the probability of functional independence but resulted in significant improvement over the full mRS scale. This improvement was most evident in patients treated early.

Practitioner, patient and public views on the acceptability of mobile stroke units in England and Wales: A mixed methods study

BACKGROUND

Evidence for Mobile Stroke Units (MSUs) demonstrates that onset to treatment times for intravenous thrombolysis can be reduced and access to mechanical thrombectomy might be improved. Despite growing use of MSUs internationally, to date there have been no studies in NHS England and NHS Wales exploring the acceptability of MSUs to clinicians, patient and public representatives and other key stakeholders, which are important when considering potential feasibility and implementation.

METHODS

This study used a mixed methods design with a cross-sectional survey and qualitative workshops and interviews between October 2023 to May 2024. Survey data were collected from clinicians involved in emergency stroke care. Qualitative data involved clinical and non-clinical professionals involved in stroke care alongside patient and public representatives with experience of stroke. Survey data were descriptively analysed while content analysis was used on open-ended questions. Qualitative data were thematically analysed, prior to triangulation using a convergent coding matrix.

RESULTS

The study results, drawn from 25 respondents to the survey and 21 participants in qualitative workshops, found that almost all participants had positive affective attitudes to the concept of MSUs. However, several key areas of concern were identified that need to be addressed prior to implementing MSUs. These concerns included how MSUs would be staffed; whether and how telemedicine could contribute; the types of economic impacts; extent to which triage systems could accurately identify stroke patients for MSUs to attend; where the base location and geographic coverage of MSUs should be, the impact of MSUs on equitable access to stroke care, and how to improve public awareness of MSUs.

CONCLUSION

Whilst MSUs are mostly acceptable to key stakeholders, numerous areas of concern need to be addressed prior to MSU implementation. We recommend further research to address these issues prior to implementation in the NHS.

Association of Mobile Stroke Unit Care and Spending, Utilization, and Death in New York City

BACKGROUND

Transport by mobile stroke units (MSUs), which provide access to computed tomography scanning and intravenous blood pressure medications and thrombolytics, reduces time to treatment and may improve short-term functional outcomes for patients with acute stroke. The longer-term clinical and financial impacts remain incompletely understood. The aim of the study was to determine whether MSU care is associated with better health, utilization, and spending outcomes for patients with suspected acute stroke.

METHODS AND RESULTS

This was a retrospective, observational study of Medicare patients transported by MSUs versus traditional ambulances in New York City, from October 2016 to December 2019. The study included 167 Medicare patients with suspected acute stroke transported by MSU and 2518 propensity score-matched controls. Primary outcomes included length of stay and discharge destination at the index hospitalization, as well as risk of repeat hospitalization, number of emergency department visits, total costs of care, and death at 1 year. Of 167 patients (mean age, 79.9 years; 56.3% women) transported by an MSU for suspected acute stroke, 61.1% had an ischemic stroke/transient ischemic attack, 7.8% had an intracerebral hemorrhage, and 31.1% had a stroke mimic or other diagnosis. Compared with propensity score-matched control patients, MSU patients were significantly more likely to receive tissue-type plasminogen activator (49.9% versus 9.4%; difference, 37.5 percentage points [95% CI, 30.2-45.6]; P<0.001) but experienced similar lengths of stay (5.9 versus 6.7 days, P=0.13) and were similarly likely to be discharged to a skilled nursing facility (15.6% versus 15.1%, P=0.86). At 1 year, MSU patients had a mortality rate of 21.6%, and control patients had a mortality rate of 28.4%, although the difference did not reach statistical significance (difference, 6.8 percentage points [95% CI, -13.3 to 0.3]; P=0.058). They had similar rates of any repeat hospitalization (24% versus 23.2%, P=0.82) and emergency department visits without hospitalization (14% versus 12%, P=0.86), and there were no significant differences in total spending or specific types of spending.

CONCLUSIONS

In this study of patients presenting with suspected acute stroke in New York City, transport by MSUs, compared with traditional ambulances, was associated with a trend toward a lower mortality rate at 1 year. Prospective trials and replication in other regions are warranted.

Mobile stroke units services in Germany: A cost-effectiveness modeling perspective on catchment zones, operating modes, and staffing

BACKGROUND AND PURPOSE

Investigating the cost-effectiveness of future mobile stroke unit (MSU) services with respect to local idiosyncrasies is essential for enabling large-scale implementation of MSU services. The aim of this study was to assess the cost-effectiveness for varying urban German settings and modes of operation.

METHODS

Costs of different operating times together with different personnel configurations were simulated. Different possible catchment zones, ischemic stroke incidence, circadian distribution, rates of alternative diagnoses, as well as missed cases were incorporated to model case coverage and patient numbers. Based on internationally reported clinical outcomes of MSUs, a 5-year Markov model was applied to analyze the cost-effectiveness for the different program setups.

RESULTS

Compared with standard stroke care, MSUs achieved an additional 0.06 quality-adjusted life years (QALYs) over a 5-year time horizon. Assuming a catchment zone of 750,000 inhabitants and 8 h/7 day operation resulted in an incremental cost-effectiveness ratio (ICER) of €37,182 per QALY from a societal perspective and €45,104 per QALY from a healthcare perspective. Lower ICERs were possible when coverage was expanded to 16 h service on 7 days per week and larger populations. Sensitivity analyses revealed that missing ischemic strokes significantly deteriorated economic performance of MSU.

CONCLUSIONS

Major determinants of cost-effectiveness should be addressed when setting up novel MSU programs. Catchment zones of more than 500,000-700,000 inhabitants and operating times of at least 12-16 h per day, 7 days per week could enable the most cost-effective MSU services in the German healthcare system.

Mothership versus Drip-and-Ship for stroke in a rural area: A French prospective observational study

BACKGROUND

The availability of mechanical thrombectomy (MT) is limited. Thus, there are two paradigms for patients living closer to a primary stroke center (PSC) than a comprehensive stroke center (CSC) capable of MT: "Mothership" (direct referral to a CSC) and "Drip-and-Ship" (referral to a PSC for imaging and thrombolysis and transfer to a CSC for thrombectomy or monitoring). We aimed to compare the prognosis of patients at three months between the two paradigms in a rural area.

MATERIALS

From September 2019 to March 2021, we prospectively included patients living closer to a PSC than the one CSC, regardless of the type of stroke or reperfusion treatment. The proportion of patients with a good functional outcome (Rankin≤2) at three months was compared between the two initial orientations for all patients and for subgroups: patients with ischemic stroke and patients treated by MT.

RESULTS

Among the 206 patients included, 103 were admitted directly to the CSC (82.5% had an ischemic stroke and 24.3% a MT) and 103 initially admitted to a PSC and then transferred to the CSC (100% had an ischemic stroke and 52.4% a MT). The proportion of patients with a good outcome was comparable between the two groups (54.5% vs. 43.7%, P=0.22). Among the 79 patients who underwent MT, the prognosis at three months was better in the Mothership group (49.3% vs. 15.3%, P=0.01).

CONCLUSION

The functional prognosis is comparable between Mothership and Drip-and-Ship paradigms in our setting, despite a trend towards a better prognosis for the Mothership. As has been shown in urban settings, the mothership paradigm also leads to a better prognosis for patients treated with MT in a rural setting.

Mobile stroke units based on rural emergency medical stations for pre-hospital intravenous thrombolysis of stroke in remote areas

OBJECTIVES

To explore a novel model of mobile stroke units (MSUs) integrated with rural emergency medical stations for pre-hospital care of stroke patients in remote areas.

METHODS

We used MSUs + Ambulance mode, where both the MSUs and conventional ambulances are sent to the patient's location. The conventional ambulance coordinates with the MSUs to choose the fastest route to meet and transfer the patient at the point along the way. We collected data from 149 patients from March 2022 to April 2023, including National Institutes of Health Stroke Scale (NIHSS) scores (on admission, 24 hours, day 7), 90-day modified Rankin Scale (mRS) scores, and other clinical variables. We performed propensity score matching (PSM) to balance the potential confounding variables between groups.

RESULTS

We found that the MSUs + Ambulance mode (OR = 12.507, 95% confidence interval [CI] [3.633, 43.061], p < 0.001) and admission NIHSS score (OR = 0.583, 95% CI [0.493, 0.690], p < 0.001) were independent prognostic risk factors for stroke patients. The MSUs + Ambulance mode reduced NIHSS scores 7 days prior to admission (OR = 0.679, 95% CI [0.563, 0.819], p < 0.001). After PSM, patients who received MSUs + Ambulance mode had a better prognosis (χ2 = 9.573, p = 0.004), as well as a lower mRS score at 90 days (Z = -3.371, p = 0.001).

CONCLUSIONS

MSUs integrated with rural emergency medical stations show the feasibility and potential benefits of pre-hospital intravenous thrombolysis for stroke patients in geographically distant regions.

Mobile Stroke Unit Management in Patients With Acute Ischemic Stroke Eligible for Intravenous Thrombolysis

Importance

Clinical trials have suggested that prehospital management in a mobile stroke unit (MSU) improves functional outcomes in patients with acute ischemic stroke who are potentially eligible for intravenous thrombolysis, but there is a paucity of real-world evidence from routine clinical practice on this topic.

Objective

To determine the association between prehospital management in an MSU vs standard emergency medical services (EMS) management and the level of global disability at hospital discharge.

Design, Setting, and Participants

This was a retrospective, observational, cohort study that included consecutive patients with a final diagnosis of ischemic stroke who received either prehospital management in an MSU or standard EMS management between August 1, 2018, and January 31, 2023. Follow-up ended at hospital discharge. The primary analytic cohort included those who were potentially eligible for IV thrombolysis. A separate, overlapping cohort including all patients regardless of diagnosis was also analyzed. Patient data were obtained from the American Heart Association's Get With The Guidelines-Stroke (GWTG-Stroke) Program, a nationwide, multicenter quality assurance registry. This analysis was completed in May 2024.

Exposure

Prehospital management in an MSU (vs standard EMS management).

Main Outcomes and Measures

The primary efficacy end point was the utility-weighted modified Rankin Scale (UW-mRS) score. The secondary efficacy end point was independent ambulation status. The coprimary safety end points were symptomatic intracranial hemorrhage (sICH) and in-hospital mortality.

Results

Of 19 433 patients (median [IQR] age, 73 [62-83] years; 9867 female [50.8%]) treated at 106 hospitals, 1237 (6.4%) received prehospital management in an MSU. Prehospital management in an MSU was associated with a better score on the UW-mRS at discharge (adjusted mean difference, 0.03; 95% CI, 0.01-0.05) and a higher likelihood of independent ambulation at discharge (53.3% [468 of 878 patients] vs 48.3% [5868 of 12 148 patients]; adjusted risk ratio [aRR], 1.08; 95% CI, 1.03-1.13). There was no statistically significant difference in sICH (5.2% [57 of 1094] vs 4.2% [545 of 13 014]; aRR, 1.30; 95% CI, 0.94-1.75]) or in-hospital mortality (5.7% [70 of 1237] vs 6.2% [1121 of 18 196]; aRR, 1.03; 95% CI, 0.78-1.27) between the 2 groups.

Conclusions and Relevance

Among patients with acute ischemic stroke potentially eligible for intravenous thrombolysis, prehospital management in an MSU compared with standard EMS management was associated with a significantly lower level of global disability at hospital discharge. These findings support policy efforts to expand access to prehospital MSU management.

Evaluation of a compact cone beam CT concept with high image fidelity for point-of-care brain imaging

Cone beam computed tomography (CBCT) has potential advantages for developing portable, cost-effective point-of-care CT systems for intracranial imaging, such as early stroke diagnosis, hemorrhage detection, and intraoperative navigation. However, large volume imaging with flat panel detector based CBCT significantly increases the scattered radiation fluence which reduces its image quality and utility. To address these issues, a compact CBCT concept with enhanced image quality was investigated for intracranial imaging. The new system features a novel antiscatter collimator and data correction method to address the challenges in imaging large volumes with CBCT. A benchtop CBCT prototype was constructed. Imaging studies with anthropomorphic phantoms showed that soft tissue visualization, Hounsfield Unit (HU) accuracy, contrast, and spatial resolution increased significantly with the proposed CBCT concept, and they were comparable to the values measured in the gold standard multidetector-row CT (MDCT) images. Contrast-to-noise ratio (CNR) in CBCT images was within 12-31% of the CNR in MDCT images. These findings indicate that a compact CBCT system integrated with effective scatter suppression techniques may have increased utility in the context of brain imaging, and the proposed approach may enable the development of point-of-care CT systems for head imaging based on flat panel detector based CBCT technology.

Race, Ethnicity, and Gender Disparities in the Management and Outcomes of Critically Ill Adults with Acute Stroke

Racial, ethnicity and sex disparities are pervasive in the evaluation and acute care of ischemic stroke patients. Administration of intravenous thrombolysis and mechanical thrombectomy are the most critical steps in ischemic stroke treatment but compared to White patients, ischemic stroke patients from minority racial and ethnic groups are less likely to receive these potentially life-saving interventions. Sex and racial disparities in intracerebral hemorrhage or subarachnoid hemorrhage treatment have not been well studied.

Hyper-Acute Stroke Systems of Care and Workflow

PURPOSE OF REVIEW

Recent stroke treatment advances have necessitated agile, broad-scale healthcare system redesign, to achieve optimal patient outcomes and access equity. Optimised hyperacute stroke care requires integrated pre-hospital, emergency department, stroke specialist, radiology, neurosurgical and endovascular neurointervention services, guided by a population-wide needs analysis. In this review, we survey system integration efforts, providing case studies, and identify common elements of successful initiatives.

RECENT FINDINGS

Different regions and nations have evolved varied acute stroke systems depending on geography, population density and workforce. However, common facilitators to these solutions have included stroke unit care as a foundation, government-clinician synergy, pre-hospital pathway coordination, service centralisation, and stroke data guiding system improvement. Further technological advantages will minimize the geographical distance disadvantages and facilitate virtual expertise redistribution to remote areas. Continued treatment advances necessitate an integrated, adaptable, population-wide trans-disciplinary approach. A well-designed clinician-led and government-supported system can facilitate hyperacute care and scaffold future system enhancements.

Emerging Adjuvant Thrombolytic Therapies for Acute Ischemic Stroke Reperfusion

Thrombolytic therapies for acute ischemic stroke are widely available but only result in recanalization early enough, to be therapeutically useful, in 10% to 30% of cases. This large gap in treatment effectiveness could be filled by novel therapies that can increase the effectiveness of thrombus clearance without significantly increasing the risk of harm. This focused update will describe the current state of emerging adjuvant treatments for acute ischemic stroke reperfusion. We focus on new treatments that are designed to (1) target different components that make up a stroke thrombus, (2) enhance endogenous fibrinolytic systems, (3) reduce stagnant blood flow, and (4) improve recanalization of distal thrombi and postendovascular thrombectomy.

Sbno1 mediates cell-cell communication between neural stem cells and microglia through small extracellular vesicles

BACKGROUND

Neural stem cells (NSCs) play a crucial role in the progress of ischemic stroke. Research on zebrafish embryonic demonstrates an association between Strawberry Notch 1 (Sbno1) and central nervous system development. However, the regulation and underlying mechanism of Sbno1 in NSCs have not been studied yet. Here, we investigated the role and the mechanism of Sbno1 in NSCs development and the potential therapeutic value of Sbno1 in ischemic stroke.

METHODS

Adeno-associated virus (AAV) was used for overexpression or knockdown of Sbno1 in vitro or in vivo. A mouse model of MCAO was established to evaluate the neuroprotective effects of AAV-Sbno1, including balance beam test, rotarod test, and strength evaluation. H&E and immunofluorescence assessed neuronal impairment. Western blot and RT-qPCR were used to detect the expression of Sbno1 and its downstream target genes. RNA-seq and western blot were performed to explore further molecular mechanisms by which Sbno1 promoted endogenous repair of NSCs and macrophages M2 polarization. CCK8 was conducted to assess the effects of Sbno1 on NSCs proliferation. The impact of Sbno1 on NSCs apoptosis was evaluated by flow cytometry. NSCs derived from small extracellular vesicles (sEV) were obtained using ultracentrifugation and identified through nanoparticle tracking analysis (NTA) and western blot analysis.

RESULTS

Our results showed that Sbno1 is highly expressed in the central nervous system, which plays a crucial role in regulating the proliferation of NSCs through the PI3k-Akt-GSK3β-Wnt/β-catenin signaling pathway. In addition, with overexpression of Sbno1 in the hippocampus, post-stroke behavioral scores were superior to the wild-type mice, and immunofluorescence staining revealed an increased number of newly generated neurons. sEV released by NSCs overexpressing Sbno1 inhibited neuroinflammation, which mechanistically impaired the activation of the microglial NF-κB and MAPK signaling pathways.

CONCLUSIONS

Our studies indicate that sbno1 promotes the proliferation of NSCs and enhances endogenous repairing through the PI3k-Akt-GSK3β-Wnt/β-catenin signaling pathway. Additionally, NSCs overexpressing sbno1 improve ischemic stroke recovery and inhibit neuroinflammation after ischemia by sEV through the MAPK and NF-κB signaling pathways.

Lifetime economic potential of mobile stroke units in acute stroke care: A model-based analysis of the drivers of cost-effectiveness

BACKGROUND AND PURPOSE

To simulate patient-level costs, analyze the economic potential of telemedicine-based mobile stroke units for acute prehospital stroke care, and identify major determinants of cost-effectiveness, based on two recent prospective trials from the United States and Germany.

METHODS

A Markov decision model was developed to simulate lifetime costs and outcomes of mobile stroke unit. The model compares diagnostic and therapeutic pathways of ischemic stroke, hemorrhagic stroke, and stroke mimic patients by conventional care or by mobile stroke units. The treatment outcomes were derived from the B_PROUD and the BEST-mobile stroke unit trials and further input parameters were derived from recent literature. Uncertainty was addressed by deterministic and probabilistic sensitivity analyses. A lifetime horizon based on the US healthcare system was adopted to evaluate different cost thresholds for mobile stroke unit and the resulting cost-effectiveness. Willingness-to-pay thresholds were set at 1x and 3x gross domestic product per capita, as recommended by the World Health Organization.

RESULTS

In the base case scenario, mobile stroke unit care yielded an incremental gain of 0.591 quality-adjusted life years per dispatch. Mobile stroke unit was highly cost-effective up to a maximum average cost of 43,067 US dollars per patient. Sensitivity analyses revealed that MSU cost-effectiveness is mainly affected by reduction of long-term disability costs. Also, among other parameters, the rate of stroke mimics patients diagnosed by MSU plays an important role.

CONCLUSION

This study demonstrated that mobile stroke unit can possibly be operated on an excellent level of cost-effectiveness in urban areas in North America with number of stroke mimic patients and long-term stroke survivor costs as major determinants of lifetime cost-effectiveness.

Potential effects of a mobile stroke unit on time to treatment and outcome in patients treated with thrombectomy or thrombolysis: A Danish-German cross-border analysis

BACKGROUND AND PURPOSE

A mobile stroke unit (MSU) reduces delays in stroke treatment by allowing thrombolysis on board and avoiding secondary transports. Due to the beneficial effect in comparison to conventional emergency medical services, current guidelines recommend regional evaluation of MSU implementation.

METHODS

In a descriptive study, current pathways of patients requiring a secondary transport for mechanical thrombectomy were reconstructed from individual patient records within a Danish (n = 122) and an adjacent German region (n = 80). Relevant timestamps included arrival times (on site, primary hospital, thrombectomy centre) as well as the initiation of acute therapy. An optimal MSU location for each region was determined. The resulting time saving was translated into averted disability-adjusted life years (DALYs).

RESULTS

For each region, the optimal MSU location required a median driving time of 35 min to a stroke patient. Time savings in the German region (median [Q1; Q3]) were 7 min (-15; 31) for thrombolysis and 35 min (15; 61) for thrombectomy. In the Danish region, the corresponding time savings were 20 min (8; 30) and 43 min (25; 66). Assuming 28 thrombectomy cases and 52 thrombolysis cases this would translate to 9.4 averted DALYs per year justifying an annual net MSU budget of $0.8M purchasing power parity dollars (PPP-$) in the German region. In the Danish region, the MSU would avert 17.7 DALYs, justifying an annual net budget of PPP-$1.7M.

CONCLUSION

The effects of an MSU can be calculated from individual patient pathways and reflect differences in the hospital infrastructure between Denmark and Germany.

Neuroprotective effects of salvianolic acids combined with Panax notoginseng saponins in cerebral ischemia/reperfusion rats concerning the neurovascular unit and trophic coupling

BACKGROUND

The neurovascular unit (NVU) and neurovascular trophic coupling (NVTC) play a key regulatory role in brain injury caused by ischemic stroke. Salvianolic acids (SAL) and Panax notoginseng saponins (PNS) are widely used in China to manage ischemic stroke. Neuroprotective effects of SAL and PNS, either taken alone or in combination, were examined in this research.

METHODS

Wistar rats were randomly divided into the following groups: Sham group (Sham), cerebral ischemia/reperfusion group (I/R), I/R with SAL group (SAL), I/R with PNS group (PNS), I/R with SAL combined with PNS (SAL + PNS), and I/R with edaravone group (EDA). Treatment was administered once daily for two days after modeling of middle cerebral artery occlusion/reperfusion (MCAO/R).

RESULTS

Compared with the I/R group, SAL, PNS, or SAL + PNS treatment reduced infarct size, improved neurological deficit score, reduced Evans blue extravasation, increased expression of CD31 and tight junction proteins (TJs), including zonula occludens-1 (ZO-1), zonula occludens-2 (ZO-2), and junctional adhesion molecule-1 (JAM-1). Furthermore, SAL, PNS, or SAL + PNS suppressed the activations of microglia and astrocyte and led to the amelioration of neuron and pericyte injury. Treatment also inhibited NVU dissociation of GFAP/PDGFRβ and Collagen IV/GFAP while upregulated the expression level of BDNF/TrkB and BDNF/NeuN.

CONCLUSIONS

SAL and PNS have significantly remedied structural and functional disorders of NVU and NVTC in I/R injury. These effects were more pronounced when SAL and PNS were combined than when used separately.

Mobile stroke units: Beyond thrombolysis

In the last decade, mobile stroke units (MSUs) have shown the potential to transform prehospital stroke care, marking a paradigm shift in delivering ultra-rapid thrombolysis and streamlining triage processes. These units bring acute stroke care directly to patients, significantly shortening treatment times. This review outlines the rationale for MSU care and discusses the potential applications beyond the original purpose of delivering thrombolysis, including large vessel occlusion detection, intracerebral hemorrhage management, and innovative forms of prehospital research.

Pre-Hospital Stroke Care beyond the MSU

PURPOSE OF REVIEW

Mobile stroke units (MSU) have established a new, evidence-based treatment in prehospital stroke care, endorsed by current international guidelines and can facilitate pre-hospital research efforts. In addition, other novel pre-hospital modalities beyond the MSU are emerging. In this review, we will summarize existing evidence and outline future trajectories of prehospital stroke care & research on and off MSUs.

RECENT FINDINGS

The proof of MSUs' positive effect on patient outcomes is leading to their increased adoption in emergency medical services of many countries. Nevertheless, prehospital stroke care worldwide largely consists of regular ambulances. Advancements in portable technology for detecting neurocardiovascular diseases, telemedicine, AI and large-scale ultra-early biobanking have the potential to transform prehospital stroke care also beyond the MSU concept. The increasing implementation of telemedicine in emergency medical services is demonstrating beneficial effects in the pre-hospital setting. In synergy with telemedicine the exponential growth of AI-technology is already changing and will likely further transform pre-hospital stroke care in the future. Other promising areas include the development and validation of miniaturized portable devices for the pre-hospital detection of acute stroke. MSUs are enabling large-scale screening for ultra-early blood-based biomarkers, facilitating the differentiation between ischemia, hemorrhage, and stroke mimics. The development of suitable point-of-care tests for such biomarkers holds the potential to advance pre-hospital stroke care outside the MSU-concept. A multimodal approach of AI-supported telemedicine, portable devices and blood-based biomarkers appears to be an increasingly realistic scenario for improving prehospital stroke care in regular ambulances in the future.

Hyperacute ischemic stroke care-Current treatment and future directions

A decade on from the first positive thrombectomy trials, hyperacute therapies for ischemic stroke continue to rapidly advance. Effective treatments remain limited to reperfusion, although several cytoprotective approaches continue to be investigated. Intravenous fibrinolytics are now demonstrated to be beneficial up to 24 h in patients selected using perfusion imaging, but their role in patients with non-disabling symptoms appears very limited. Tenecteplase is superior to alteplase in meta-analysis of the latest trials, and adjuvant thrombolytics are an area of active investigation. Endovascular thrombectomy is beneficial in a wide range of anterior and posterior circulation large vessel occlusions up to 24 h after onset with the more distal occlusions, mild presentations, and >24 h window being the main frontiers to be tested in ongoing trials. Imaging parameters are prognostic but appear not to modify the relative treatment benefit of thrombectomy versus standard medical care. Therefore, deciding who not to treat with thrombectomy is a key clinical challenge that requires careful but rapid integration of clinical, imaging, and patient preference considerations. Systems of care to accelerate delivery of these highly effective therapies will maximize benefits for the greatest number of patients with stroke.

Fibrinolytic Agents in Thromboembolic Diseases: Historical Perspectives and Approved Indications

Fibrinolytic agents catalyze the conversion of the inactive proenzyme plasminogen into the active protease plasmin, degrading fibrin within the thrombus and recanalizing occluded vessels. The history of these medications dates to the discovery of the first fibrinolytic compound, streptokinase, from bacterial cultures in 1933. Over time, researchers identified two other plasminogen activators in human samples, namely urokinase and tissue plasminogen activator (tPA). Subsequently, tPA was cloned using recombinant DNA methods to produce alteplase. Several additional derivatives of tPA, such as tenecteplase and reteplase, were developed to extend the plasma half-life of tPA. Over the past decades, fibrinolytic medications have been widely used to manage patients with venous and arterial thromboembolic events. Currently, alteplase is approved by the U.S. Food and Drug Administration (FDA) for use in patients with pulmonary embolism with hemodynamic compromise, ST-segment elevation myocardial infarction (STEMI), acute ischemic stroke, and central venous access device occlusion. Reteplase and tenecteplase have also received FDA approval for treating patients with STEMI. This review provides an overview of the historical background related to fibrinolytic agents and briefly summarizes their approved indications across various thromboembolic diseases.

Mobile Stroke Units in Acute Ischemic Stroke: A Comprehensive Systematic Review and Meta-Analysis of 5 "T Letter" Domains

Intravenous thrombolysis (IVT) may be administered to stroke patients requiring immediate treatment more quickly than emergency medical services if certain conditions are met. These conditions include the presence of mobile stroke units (MSUs) with on-site treatment teams and a computed tomography scanner. We compared clinical outcomes of MSU conventional therapy by emergency medical services through a systematic review and meta-analysis. We searched key electronic databases from inception till September 2021. The primary outcomes were mortality at 7 and 90 days. The secondary outcomes included the modified Rankin Scale score at 90 days, alarm to IVT or intra-arterial recanalization, and time from symptom onset or last known well to thrombolysis. We included 19 controlled trials and cohort studies to conduct our final analysis. Our comparison revealed that 90-day mortality significantly decreased in the MSU group compared with the conventional care group [risk ratio = 0.82; 95% confidence interval (CI), 0.71-0.95], while there was no significant difference at 7 days (risk ratio = 0.89; 95% CI, 0.69-1.15). MSU achieved greater functional independence (modified Rankin Scale = 0-2) at 90 days (risk ratio = 1.08; 95% CI, 1.01-1.16). MSU was associated with shorter alarm to IVT or intra-arterial recanalization time (mean difference = -29.69; 95% CI, -34.46 to -24.92), treating patients in an earlier time window, as shown through symptom onset or last known well to thrombolysis (mean difference = -36.79; 95% CI, -47.48 to -26.10). MSU-treated patients had a lower rate of 90-day mortality and better 90-day functional outcomes by earlier initiation of IVT compared with conventional care.

Statistical Analysis Plan for the INTEnsive Ambulance-Delivered Blood Pressure Reduction in Hyper-ACute Stroke Trial

INTRODUCTION

Recruitment is complete in the fourth INTEnsive ambulance-delivered blood pressure Reduction in hyper-ACute stroke Trial (INTERACT4), a multicenter, prospective, randomized, open-label, blinded endpoint assessed trial of prehospital blood pressure (BP) lowering initiated in the ambulance for patients with a suspected acute stroke and elevated BP in China. According to the registered and published trial protocol and developed by the blinded trial Steering Committee and Operations team, this manuscript outlines a detailed statistical analysis plan for the trial prior to database lock.

METHODS

Patients were randomized (1:1) to intensive (target systolic BP 130-140 mm Hg within 30 min) or guideline-recommended BP management (BP lowering only considered if systolic BP >220 mm Hg) group. Primary outcome is an ordinal analysis of the full range of scores on the modified Rankin scale at 90 days. A modified sample size of 2,320 was estimated to provide 90% power to detect a 22% reduction in the odds (common odds ratio of 0.78) of a worse functional outcome using ordinal logistic regression, on the assumption of 5% patients with missing outcome and 6% patients with a stroke mimic.

CONCLUSION

The statistical analysis plan for the trial has been developed to ensure transparent, verifiable, and prespecified analysis and to avoid potential bias in the evaluation of the trial intervention.

Using 30-day modified rankin scale score to predict 90-day score in patients with intracranial hemorrhage: Derivation and validation of prediction model

Whether 30-day modified Rankin Scale (mRS) scores can predict 90-day scores is unclear. This study derived and validated a model to predict ordinal 90-day mRS score in an intracerebral hemorrhage (ICH) population using 30-day mRS values and routinely available baseline variables. Adults enrolled in the Antihypertensive Treatment of Acute Cerebral Hemorrhage-2 (ATACH-2) trial between May 2011 and September 2015 with acute ICH, who were alive at 30 days and had mRS scores reported at both 30 and 90 days were included in this post-hoc analysis. A proportional odds regression model for predicting ordinal 90-day mRS scores was developed and internally validated using bootstrapping. Variables in the model included: mRS score at 30 days, age (years), hematoma volume (cm3), hematoma location (deep [basal ganglia, thalamus], lobar, or infratentorial), presence of intraventricular hemorrhage (IVH), baseline Glasgow Coma Scale (GCS) score, and National Institutes of Health Stroke Scale (NIHSS) score at randomization. We assessed model fit, calibration, discrimination, and agreement (ordinal, dichotomized functional independence), and EuroQol-5D ([EQ-5D] utility weighted) between predicted and observed 90-day mRS. A total of 898/1000 participants were included. Following bootstrap internal validation, our model (calibration slope = 0.967) had an optimism-corrected c-index of 0.884 (95% CI = 0.873-0.896) and R2 = 0.712 for 90-day mRS score. The weighted ĸ for agreement between observed and predicted ordinal 90-day mRS score was 0.811 (95% CI = 0.787-0.834). Agreement between observed and predicted functional independence (mRS score of 0-2) at 90 days was 74.3% (95% CI = 69.9-78.7%). The mean ± SD absolute difference between predicted and observed EQ-5D-weighted mRS score was negligible (0.005 ± 0.145). This tool allows practitioners and researchers to utilize clinically available information along with the mRS score 30 days after ICH to reliably predict the mRS score at 90 days.

Artificial intelligence to enhance prehospital stroke diagnosis and triage: a perspective

As health systems organize to deliver the highest quality stroke care to their patients, there is increasing emphasis being placed on prehospital stroke recognition, accurate diagnosis, and efficient triage to improve outcomes after stroke. Emergency medical services (EMS) personnel currently rely heavily on dispatch accuracy, stroke screening tools, bypass protocols and prehospital notification to care for patients with suspected stroke, but novel tools including mobile stroke units and telemedicine-enabled ambulances are already changing the landscape of prehospital stroke care. Herein, the authors provide our perspective on the current state of prehospital stroke diagnosis and triage including several of these emerging trends. Then, we provide commentary to highlight potential artificial intelligence (AI) applications to improve stroke detection, improve accurate and timely dispatch, enhance EMS training and performance, and develop novel stroke diagnostic tools for prehospital use.

Using Negative Control Populations to Assess Unmeasured Confounding and Direct Effects

Sometimes treatment effects are absent in a subgroup of the population. For example, penicillin has no effect on severe symptoms in individuals infected by resistant Staphylococcus aureus , and codeine has no effect on pain in individuals with certain polymorphisms in the CYP2D6 enzyme. Subgroups where a treatment is ineffective are often called negative control populations or placebo groups. They are leveraged to detect bias in different disciplines. Here we present formal criteria that justify the use of negative control populations to rule out unmeasured confounding and mechanistic (direct) causal effects. We further argue that negative control populations, satisfying our formal conditions, are available in many settings, spanning from clinical studies of infectious diseases to epidemiologic studies of public health interventions. Negative control populations can also be used to rule out placebo effects in unblinded randomized experiments. As a case study, we evaluate the effect of mobile stroke unit dispatches on functional outcomes at discharge in individuals with suspected stroke, using data from a large trial. Our analysis supports the hypothesis that mobile stroke units improve functional outcomes in these individuals.

A promising frontier: targeting NETs for stroke treatment breakthroughs

Stroke is a prevalent global acute cerebrovascular condition, with ischaemic stroke being the most frequently occurring type. After a stroke, neutrophils accumulate in the brain and subsequently generate and release neutrophil extracellular traps (NETs). The accumulation of NETs exacerbates the impairment of the blood‒brain barrier (BBB), hampers neovascularization, induces notable neurological deficits, worsens the prognosis of stroke patients, and can facilitate the occurrence of t-PA-induced cerebral haemorrhage subsequent to ischaemic stroke. Alternative approaches to pharmacological thrombolysis or endovascular thrombectomy are being explored, and targeting NETs is a promising treatment that warrants further investigation.

Addressing Disparities in Acute Stroke Management and Prognosis

There are now abundant data demonstrating disparities in acute stroke management and prognosis; however, interventions to reduce these disparities remain limited. This special report aims to provide a critical review of the current landscape of disparities in acute stroke care and highlight opportunities to use implementation science to reduce disparities throughout the early care continuum. In the prehospital setting, stroke symptom recognition campaigns that have been successful in reducing prehospital delays used a multilevel approach to education, including mass media, culturally tailored community education, and professional education. The mobile stroke unit is an organizational intervention that has the potential to provide more equitable access to timely thrombolysis and thrombectomy treatments. In the hospital setting, interventions to address implicit biases among health care providers in acute stroke care decision-making are urgently needed as part of a multifaceted approach to advance stroke equity. Implementing stroke systems of care interventions, such as evidence-based stroke care protocols at designated stroke centers, can have a broader public health impact and may help reduce geographic, racial, and ethnic disparities in stroke care, although further research is needed. The long-term impact of disparities in acute stroke care cannot be underestimated. The consistent trend of longer time to treatment for Black and Hispanic people experiencing stroke has direct implications on long-term disability and independence after stroke. A learning health system model may help expedite the translation of evidence-based interventions into clinical practice to reduce disparities in stroke care.

Prehospital stroke care in Singapore

ABSTRACT

Due to the narrow window of opportunity for stroke therapeutics to be employed, effectiveness of stroke care systems is predicated on the efficiency of prehospital stroke systems. A robust prehospital stroke system of care that provides a rapid and well-coordinated response maximises favourable poststroke outcomes, but achieving this presents a unique set of challenges dependent on demographic and geographical circumstances. Set in the context of a highly urbanised first-world nation with a rising burden of stroke, Singapore's prehospital stroke system has evolved to reflect the environment in which it operates. This review aims to characterise the current state of prehospital stroke care in Singapore, covering prehospital aspects of the stroke survival chain from symptom onset till arrival at the emergency department. We identify areas for improvement and innovation, as well as provide insights into the possible future of prehospital stroke care in Singapore.

Reporting and analysis of process-of-care time measures in clinical trials for hyperacute stroke interventions: a scoping review protocol

OBJECTIVE

The objective of this scoping review is to investigate the reporting and comparison of process-of-care time measures in hyperacute stroke trials and systematic reviews of trials (subsequently referred to as "studies").

INTRODUCTION

Stroke is a leading cause of death and disability worldwide. A crucial factor in determining the effectiveness of stroke care in improving patient outcomes is time; therefore, time measures are frequently reported in studies of hyperacute stroke interventions. However, there is inconsistency in how these measures are reported and compared. Furthermore, there is a lack of clarity in how compatible the reporting methods are with the statistical analysis methods.

INCLUSION CRITERIA

This scoping review will include studies that report and/or compare time measures between key events of interest in the delivery of hyperacute stroke care. Studies of thrombolytic therapy and/or thrombectomy, as well as controlled trials of mobile stroke unit interventions, will be included.

METHODS

The scoping review will be conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) and the JBI methodology for scoping reviews. The search will be executed in MEDLINE (PubMed), Embase (Ovid), and clinical trial registries ANZCTR, ISRCTN, and ClinicalTrials.gov. Title and abstract screening will be followed by full-text screening and subsequent data extraction from eligible studies. The results from this scoping review will be presented in tables and narratively summarized.

REVIEW REGISTRATION

Open Science Framework https://osf.io/y98wz.

Optimization of sensitivity and specificity of a biomarker-based blood test (LVOCheck-Opti): A protocol for a multicenter prospective observational study of patients suspected of having a stroke

Introduction

Acute ischemic stroke (AIS) is a time-critical medical emergency. For patients with large-vessel occlusions (LVO), mechanical thrombectomy (MT) is the gold-standard treatment. Mobile Stroke Units (MSUs) provide on-site diagnostic capabilities via computed tomography (CT) and have been shown to improve functional outcomes in stroke patients, but are cost-efficient only in urban areas. Blood biomarkers have recently emerged as possible alternative to cerebral imaging for LVO diagnosis. Prehospital LVO diagnosis offers the potential to transport patients directly to centers that have MT treatment available. In this study, we assess the accuracy of combining two biomarkers, HFABP and NT-proBNP, with clinical indicators to detect LVO using ultra-early prehospital blood samples. The study was registered in the German Clinical Trials Register (DRKS-ID: DRKS00030399).

Methods and analysis

We plan a multicenter prospective observational study with 800 patients with suspected stroke enrolled within 24 h of symptom onset. Study participants will be recruited at three sites (MSUs) in Berlin, Germany. Blood-samples will be taken pre-hospitally at the scene and tested for HFABP and NT-proBNP levels. Additional clinical data and information on final diagnosis will be collected and documented in an electronic case report form (eCRF). Sensitivity and specificity of the combination will be calculated through iterative permutation-response calculations.

Discussion

This study aims to evaluate the diagnostic capabilities of a combination of the biomarkers HFABP and NT-proBNP in LVO prediction. In contrast to most other biomarker studies to date, by employing MSUs as study centers, ultra-early levels of biomarkers can be analyzed. Point-of-care LVO detection in suspected stroke could lead to faster treatment in both urban and rural settings and thus improve functional outcomes on a broader scale.

Clinical trial registration

Deutsches Register klinischer Studien https://drks.de/search/de/trial/DRKS00030399, DRKS00030399.

Transnasal cooling: New prospect of selective hypothermia in acute ischemic stroke

Rapid and selective therapeutic hypothermia is a promising neuroprotective method for acute ischemic stroke. A recent study developed a simple but efficient technique of transnasal cooling, in which air at ambient temperature was passed through standard nasal cannula to induce evaporative cooling of the brain. Selective brain temperature decrease was achieved within 25 minutes in piglets. It is a major step forward to initiate early brain cooling. However, it is still necessary to devise a more comprehensive strategy to enhance the benefits of selective brain cooling in the era of effective reperfusion.

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.

Brain FADE syndrome: the final common pathway of chronic inflammation in neurological disease

Importance

While the understanding of inflammation in the pathogenesis of many neurological diseases is now accepted, this special commentary addresses the need to study chronic inflammation in the propagation of cognitive Fog, Asthenia, and Depression Related to Inflammation which we name Brain FADE syndrome. Patients with Brain FADE syndrome fall in the void between neurology and psychiatry because the depression, fatigue, and fog seen in these patients are not idiopathic, but instead due to organic, inflammation involved in neurological disease initiation.

Observations

A review of randomized clinical trials in stroke, multiple sclerosis, Parkinson's disease, COVID, traumatic brain injury, and Alzheimer's disease reveal a paucity of studies with any component of Brain FADE syndrome as a primary endpoint. Furthermore, despite the relatively well-accepted notion that inflammation is a critical driving factor in these disease pathologies, none have connected chronic inflammation to depression, fatigue, or fog despite over half of the patients suffering from them.

Conclusions and relevance

Brain FADE Syndrome is important and prevalent in the neurological diseases we examined. Classical "psychiatric medications" are insufficient to address Brain FADE Syndrome and a novel approach that utilizes sequential targeting of innate and adaptive immune responses should be studied.

What Will the Mobile Stroke Unit of the Future Look Like, and Will EEG Have a Role?

There have been major advances in prehospital evaluation and care of stroke patients in the past 2 decades. Because about half of patients experiencing stroke arrive to the emergency department (ED) by ambulance, emergency medical service providers are in a unique position to positively affect stroke outcomes. One development of great interest is the implementation of mobile stroke units (MSUs), large ambulances outfitted with mobile CT scanners, point-of-care laboratories, and access to clinical stroke expertise (either in-person or remotely).1.

A systematic review of ambulance service-based randomised controlled trials in stroke

BACKGROUND

Treatment for stroke is time-dependent, and ambulance services play a vital role in the early recognition, assessment and transportation of stroke patients. Innovations which begin in ambulance services to expedite delivery of treatments for stroke are developing. However, research delivery in ambulance services is novel, developing and not fully understood.

AIMS

To synthesise literature encompassing ambulance service-based randomised controlled interventions for acute stroke with consideration to the characteristics of the type of intervention, consent modality, time intervals and issues unique to research delivery in ambulance services. Online searches of MEDLINE, EMBASE, Web of Science, CENTRAL and WHO IRCTP databases and hand searches identified 15 eligible studies from 538. Articles were heterogeneous in nature and meta-analysis was partially available as 13 studies reported key time intervals, but terminology varied. Randomised interventions were evident across all points of contact with ambulance services: identification of stroke during the call for help, higher dispatch priority assigned to stroke, on-scene assessment and clinical interventions, direct referral to comprehensive stroke centres and definitive care delivery at scene. Consent methods ranged between informed patient, waiver and proxy modalities with country-specific variation. Challenges unique to the prehospital setting comprise the geographical distribution of ambulance resources, low recruitment rates, prolonged recruitment phases, management of investigational medicinal product and incomplete datasets.

CONCLUSION

Research opportunities exist across all points of contact between stroke patients and ambulance services, but randomisation and consent remain novel. Early collaboration and engagement between trialists and ambulance services will alleviate some of the complexities reported.

REGISTRATION NUMBER

PROSPERO 2018CRD42018075803.

Epidemiology, organization, diagnosis and treatment of acute ischemic stroke

The management of acute ischemic stroke is changing. Over the period of 2010-2050, the number of incident strokes is expected to be more than double. Rapid access to mechanical thrombectomy for patients with large vessel occlusion is critically associated with their functional outcome. Moreover, patients with first pass effect had a better clinical outcome, lower mortality, and fewer procedural adverse events. We discuss some advances in acute ischemic stroke regarding the organization, the diagnosis and the treatment.

Priorities for Advancements in Neuroimaging in the Diagnostic Workup of Acute Stroke

STAIR XII (12th Stroke Treatment Academy Industry Roundtable) included a workshop to discuss the priorities for advancements in neuroimaging in the diagnostic workup of acute ischemic stroke. The workshop brought together representatives from academia, industry, and government. The participants identified 10 critical areas of priority for the advancement of acute stroke imaging. These include enhancing imaging capabilities at primary and comprehensive stroke centers, refining the analysis and characterization of clots, establishing imaging criteria that can predict the response to reperfusion, optimizing the Thrombolysis in Cerebral Infarction scale, predicting first-pass reperfusion outcomes, improving imaging techniques post-reperfusion therapy, detecting early ischemia on noncontrast computed tomography, enhancing cone beam computed tomography, advancing mobile stroke units, and leveraging high-resolution vessel wall imaging to gain deeper insights into pathology. Imaging in acute ischemic stroke treatment has advanced significantly, but important challenges remain that need to be addressed. A combined effort from academic investigators, industry, and regulators is needed to improve imaging technologies and, ultimately, patient outcomes.

Most Promising Approaches to Improve Stroke Outcomes: The Stroke Treatment Academic Industry Roundtable XII Workshop

The Stroke Treatment Academic Industry Roundtable XII included a workshop to discuss the most promising approaches to improve outcome from acute stroke. The workshop brought together representatives from academia, industry, and government representatives. The discussion examined approaches in 4 epochs: pre-reperfusion, reperfusion, post-reperfusion, and access to acute stroke interventions. The participants identified areas of priority for developing new and existing treatments and approaches to improve stroke outcomes. Although many advances in acute stroke therapy have been achieved, more work is necessary for reperfusion therapies to benefit the most possible patients. Prioritization of promising approaches should help guide the use of resources and investigator efforts.