Interhospital Transfer Before Thrombectomy Is Associated With Delayed Treatment and Worse Outcome in the STRATIS Registry (Systematic Evaluation of Patients Treated With Neurothrombectomy Devices for Acute Ischemic Stroke)

Role of Stroke Scales and Scores in Cerebrovascular Disease

This article provides a comprehensive review of widely utilized stroke scales in both routine clinical settings and research. These scales are crucial for planning treatment, predicting outcomes, and helping stroke patients recover. They also play a pivotal role in planning, executing, and comprehending stroke clinical trials. Each scale presents distinct advantages and limitations, and the authors explore these aspects within the article. The authors' intention is to provide the reader with practical insights for a clear understanding of these scales, and their effective use in their clinical practice.

Interhospital Transfer for Endovascular Stroke Treatment in Canada: Results From the OPTIMISE Registry

BACKGROUND

Interhospital transfer for patients with stroke due to large vessel occlusion for endovascular thrombectomy (EVT) has been associated with treatment delays.

METHODS

We analyzed data from Optimizing Patient Treatment in Major Ischemic Stroke With EVT, a quality improvement registry to support EVT implementation in Canada. We assessed for unadjusted differences in baseline characteristics, time metrics, and procedural outcomes between patients with large vessel occlusion transferred for EVT and those directly admitted to an EVT-capable center.

RESULTS

Between January 1, 2018, and December 31, 2021, a total of 6803 patients received EVT at 20 participating centers (median age, 73 years; 50% women; and 50% treated with intravenous thrombolysis). Patients transferred for EVT (n=3376) had lower rates of M2 occlusion (22% versus 27%) and higher rates of basilar occlusion (9% versus 5%) compared with those patients presenting directly at an EVT-capable center (n=3373). Door-to-needle times were shorter in patients receiving intravenous thrombolysis before transfer compared with those presenting directly to an EVT center (32 versus 36 minutes). Patients transferred for EVT had shorter door-to-arterial access times (37 versus 87 minutes) but longer last seen normal-to-arterial access times (322 versus 181 minutes) compared with those presenting directly to an EVT-capable center. No differences in arterial access-to-reperfusion times, successful reperfusion rates (85% versus 86%), or adverse periprocedural events were found between the 2 groups. Patients transferred to EVT centers had a similar likelihood for good functional outcome (modified Rankin Scale score, 0-2; 41% versus 43%; risk ratio, 0.95 [95% CI, 0.88-1.01]; adjusted risk ratio, 0.98 [95% CI, 0.91-1.05]) and a higher risk for all-cause mortality at 90 days (29% versus 25%; risk ratio, 1.15 [95% CI, 1.05-1.27]; adjusted risk ratio, 1.14 [95% CI, 1.03-1.28]) compared with patients presenting directly to an EVT center.

CONCLUSIONS

Patients transferred for EVT experience significant delays from the time they were last seen normal to the initiation of EVT.

Large vessel occlusive stroke with milder baseline severity shows better collaterals and reduced harm from thrombectomy transfer delays

BACKGROUND

Patients with large vessel occlusion (LVO) stroke presenting with milder baseline clinical severity are common and require endovascular thrombectomy. However, such patients are difficult to recognize using pre-hospital severity-based triage tools and therefore are likely to require a secondary inter-hospital transfer if transported to a non-thrombectomy center. Given the potential for milder severity to represent better underlying cerebrovascular collateral circulation, it is unknown whether transfer delays are still associated with poorer post-stroke outcomes in this patient group.

AIMS

We primarily aimed to examine whether the harmful effect of inter-hospital transfer delay for thrombectomy was different for LVO patients with mild or severe deficits. Secondarily, we also investigated whether imaging markers of collateral circulation were different between severity groups.

METHODS

Registry data from two large Australian thrombectomy centers were used to identify all directly presenting and secondarily transferred LVO patients undergoing thrombectomy, divided into those with lower (NIHSS < 10) and higher (NIHSS ⩾ 10) baseline deficits. The primary outcome was the functional independence or return to baseline defined as modified Rankin Scale 0-2 or baseline at 90 days. Patients with complete baseline CT-perfusion data were analyzed for imaging markers of collateral circulation by baseline severity group.

RESULTS

A total of 1210 LVO patients undergoing thrombectomy were included, of which 273 (22.6%) had lower baseline severity. Despite similar thrombolysis and recanalization rates, transferred patients had lower odds of achieving the primary outcome compared to the primary presentation to a thrombectomy center, where baseline severity was higher (adjusted odds ratio (aOR) 0.759 (95% CI 0.576-0.999)), but not when severity was lower (aOR 1.357 (95% CI 0.764-2.409), p-interaction = 0.122). In the imaging analysis of 436 patients, those with milder severity showed smaller median ischemic core volumes (12.6 (IQR 0.0-17.9) vs 27.5 (IQR 6.5-37.1) mL, p < 0.001)), higher median perfusion mismatch ratio (10.8 (IQR 4.8-54.5) vs 6.6 (IQR 3.5-16.5), p < 0.001), and lower median hypoperfusion intensity ratio (0.25 (IQR 0.18-0.38) vs 0.40 (IQR 0.22-0.57), p < 0.001).

DISCUSSION

Patients receiving secondary inter-hospital transfer for thrombectomy had poorer outcomes compared to those presenting directly to a thrombectomy center if baseline deficits were severe, but this difference was not observed when baseline deficits were milder. This result may potentially be due to our secondary findings of significantly improved collateral circulation markers in lower-severity LVO patients. As such, failure of pre-hospital screening tools to detect lower-severity LVO patients for pre-hospital bypass to a thrombectomy center may not necessarily deleteriously affect outcome.

DATA ACCESS STATEMENT

Anonymized data not published within this article will be made available on request from any qualified investigator.

Earlier Endovascular Thrombectomy and Mortality in Patients with Anterior Circulation Large Vessel Occlusion: A Propensity-Matched Analysis of the Stroke Thrombectomy and Aneurysm Registry

BACKGROUND

The definitive impact of onset to arterial puncture time (OPT) on 90-day mortality after endovascular thrombectomy (EVT) in patients with acute ischemic stroke (AIS) caused by anterior circulation large vessel occlusion (LVO) remains unknown. The present study aimed to evaluate the influence of OPT on 90-day mortality in anterior circulation AIS-LVO patients who underwent EVT.

METHODS

Data from 33 international centers were retrospectively analyzed. The receiver operating characteristic curve analysis was used to identify a cutoff for OPT. A propensity score-matched analysis was performed. The primary outcome was 90-day mortality (modified Rankin Scale [mRS] 6). Secondary outcomes included mortality at discharge, 90-day good outcome (mRS 0-2), 90-day poor outcome (mRS 5-6), successful recanalization (defined as postprocedure modified Thrombolysis in Cerebral Infarction scale ≥2b), and intracranial hemorrhage.

RESULTS

A total of 2842 AIS-LVO patients with EVT were included. The cutoff for OPT for 90-day mortality was 180 min. Of these 378 patients had OPT <180 min and 378 patients had OPT ≥180 min in the propensity score-matched cohort (n = 756). Patients with OPT <180 min were less likely to have 90-day mortality (odds ratio [OR] 0.70, 95% confidence interval [CI] 0.51-0.96) and poor outcome (OR 0.71, 95% CI 0.53-0.96), and more likely to have 90-day good outcome (OR 1.55, 95% CI 1.16-2.08). Other outcomes showed no significant differences.

CONCLUSIONS

This study showed that OPT <180 min was less related to 90-day mortality and poor outcome, and more to 90-day good outcome in AIS-LVO patients who underwent EVT.

Upfront vascular imaging in acute stroke: Impact on thrombectomy transfer time at a primary stroke center

OBJECTIVES

Early cerebral arterial imaging is currently only recommended in the subgroup of acute ischemic stroke (AIS) patients suspected of having large vessel occlusion (LVO). There is limited data on the impact of early cerebrovascular imaging in all suspected AIS patients presenting within 24 h of symptom onset and the impact on door in-door out (DIDO) time.

MATERIALS AND METHODS

In January 2020, our Primary Stroke Center implemented a protocol to perform upfront head and neck CT angiography (CTA) with initial non-contrast CT head for all suspected ischemic stroke patients screening positive for BE-FAST stroke symptoms within 24 h from last known normal time. We retrospectively reviewed IV alteplase and thrombectomy-eligible patients before (January 1-December 31, 2019) and after protocol implementation (January 1, 2020-June 30, 2022).

RESULTS

Of 86 patients meeting study criteria, up-front CTA was associated with significant reductions in door-to-CTA start (median 37 vs 15 min, p = 0.003), door-to-CTA result (median 83 vs 52 min, p = 0.023) and DIDO times (median 150 vs 106 min, p = 0.023). There was no significant difference in door-to-needle time before and after protocol implementation (median 48 vs 43 min, p = 0.450).

CONCLUSION

Up-front cerebrovascular imaging with CTA in suspected AIS patients presenting within 24 h resulted in shorter DIDO times without delaying door-to-needle times. Primary Stroke Centers should consider this approach to detect LVO early and expedite patient transport to thrombectomy capable centers.

Outcome of stroke patients eligible to mechanical thrombectomy managed by spoke center, primary stroke center or comprehensive stroke center in the East of France

BACKGROUND AND PURPOSE

Patients with suspected stroke are referred to the nearest hospital and are managed either in a spoke center (SC), a primary stroke center (PSC), or a comprehensive stroke center (CSC) in order to benefit from early intravenous thrombolysis (IVT). In case of large vessel occlusion (LVO), mechanical thrombectomy (MT) is only performed in the CSC, whereas the effectiveness of MT is highly time-dependent. There is a debate about the best management model of patients with suspected LVO. Therefore, we aimed to compare functional and safety outcomes of LVO patients eligible for MT managed through our regional telestroke system.

METHOD

We performed a retrospective analysis of our observational prospective clinical registry in all consecutive subjects with LVO within six hours of onset who were admitted to the SC, PSC, or CSC in the east of France between October 2017 and November 2022. The primary endpoint was the functional independence defined as modified Rankin scale (mRS) score 0 to 2 at 90 days. Secondary endpoints were functional outcome, early neurological improvement, symptomatic intracranial hemorrhage and 90-day mortality.

RESULTS

Among the 794 included patients with LVO who underwent MT, 122 (15.4%) were managed by a SC, 403 (50.8%) were first admitted to a PSC, and 269 (33.9%) were first admitted to the CSC. The overall median NIHSS and ASPECTS score were 16 and 8, respectively. Multivariate analysis did not find any significant difference for the primary endpoint between patients managed by PSC versus CSC (OR 1.06 [95% CI 0.64;1.76], P=0.82) and between patient managed by SC versus CSC (OR 0.69 [0.34;1.40], P=0.30). No difference between the three groups was found except for the parenchymal hematoma rate between PSC and CSC (15.7 versus 7.4%, OR 2.25 [1.07;4.74], P=0.032).

CONCLUSIONS

Compared with a first admission to a CSC, the clinical outcomes of stroke patients with LVO eligible for MT first admitted to a SC or a PSC are similar.

Arterial Recanalization During Interhospital Transfer for Thrombectomy

BACKGROUND

Patients with acute ischemic stroke harboring a large vessel occlusion admitted to nonendovascular-capable centers often require interhospital transfer for thrombectomy. We evaluated the incidence and predictors of arterial recanalization during transfer, as well as the relationship between interhospital recanalization and clinical outcomes.

METHODS

We analyzed data from 2 cohorts of patients with an anterior circulation large vessel occlusion transferred for consideration of thrombectomy to a comprehensive center, with arterial imaging at the referring hospital and on comprehensive stroke center arrival. Interhospital recanalization was determined by comparison of the baseline and posttransfer arterial imaging and was defined as revised arterial occlusive lesion (rAOL) score 2b to 3. Pretransfer variables independently associated with interhospital recanalization were studied using multivariable logistic regression analysis.

RESULTS

Of the 520 included patients (Montpellier, France, n=237; Stanford, United States, n=283), 111 (21%) experienced interhospital recanalization (partial [rAOL=2b] in 77% and complete [rAOL=3] in 23%). Pretransfer variables independently associated with recanalization were intravenous thrombolysis (adjusted odds ratio, 6.8 [95% CI, 4.0-11.6]), more distal occlusions (intracranial carotid occlusion as reference: adjusted odds ratio, 2.0 [95% CI, 0.9-4.5] for proximal first segment of the middle cerebral artery, 5.1 [95% CI, 2.3-11.5] for distal first segment of the middle cerebral artery, and 5.0 [95% CI, 2.1-11.8] for second segment of the middle cerebral artery), and smaller clot burden (clot burden score 0-4 as reference: adjusted odds ratio, 3.4 [95% CI, 1.5-7.6] for 5-7 and 5.6 [95% CI, 2.4-12.7] for 8-9). Recanalization on arrival at the comprehensive center was associated with less interhospital infarct growth (rAOL, 0-2a: 11.6 mL; rAOL, 2b: 2.2 mL; rAOL, 3: 0.6 mL; Ptrend<0.001) and greater interhospital National Institutes of Health Stroke Scale score improvement (0 versus -5 versus -6; Ptrend<0.001). Interhospital recanalization was associated with reduced 3-month disability (adjusted common odds ratio, 2.51 [95% CI, 1.68-3.77]) with greater benefit from complete than partial recanalization.

CONCLUSIONS

Recanalization is frequently observed during interhospital transfer for thrombectomy and is strongly associated with favorable outcomes, even when partial. Broadening thrombolysis indications in primary centers, and developing therapies that increase recanalization during transfer, will likely improve clinical outcomes.

Introducing the Futile Recanalization Prediction Score (FRPS): A Novel Approach to Predict and Mitigate Ineffective Recanalization after Endovascular Treatment of Acute Ischemic Stroke

Objective: This study aims to develop and validate the Futile Recanalization Prediction Score (FRPS), a novel tool designed to predict the severity risk of FR and aid in pre- and post-EVT risk assessments. Methods: The FRPS was developed using a rigorous process involving the selection of predictor variables based on clinical relevance and potential impact. Initial equations were derived from previous meta-analyses and refined using various statistical techniques. We employed machine learning algorithms, specifically random forest regression, to capture nonlinear relationships and enhance model performance. Cross-validation with five folds was used to assess generalizability and model fit. Results: The final FRPS model included variables such as age, sex, atrial fibrillation (AF), hypertension (HTN), diabetes mellitus (DM), hyperlipidemia, cognitive impairment, pre-stroke modified Rankin Scale (mRS), systolic blood pressure (SBP), onset-to-puncture time, sICH, and NIHSS score. The random forest model achieved a mean R-squared value of approximately 0.992. Severity ranges for FRPS scores were defined as mild (FRPS < 66), moderate (FRPS 66-80), and severe (FRPS > 80). Conclusions: The FRPS provides valuable insights for treatment planning and patient management by predicting the severity risk of FR. This tool may improve the identification of candidates most likely to benefit from EVT and enhance prognostic accuracy post-EVT. Further clinical validation in diverse settings is warranted to assess its effectiveness and reliability.

Education and training in neurology: developments and future challenges

BACKGROUND AND PURPOSE

Training and education is essential for best practice medicine and is especially important in a rapidly evolving field such as neurology. Due to improved imaging techniques and laboratory testing, there is a better understanding of the pathophysiology of diseases. As a result more treatments have become available. The most important developments in neurology over the last two decades and their effect on training and education are described. In addition, how future training should be aware of the challenges ahead of us is described.

METHODS

This is a narrative review describing developments and challenges based on personal experience and the literature.

RESULTS

Due to major developments in radiological and immunological testing, major changes have been seen in different subspecialties of neurology, including but not limited to, the treatment of ischaemic stroke, the development of new entities in the field of demyelinating diseases and auto-immune encephalitis, and diffuse glioma. These developments challenge the education and training in neurology with, ahead of us, technological developments, an aging population, and potentially more superspecialization.

CONCLUSION

Although there are differences in the training curricula between European countries, the developments and future challenges within the field of neurology are very similar. In the development of future curricula it is important to face these developments and challenges and to adapt to them.

A comprehensive Exdia TRF-LFIA for simultaneous quantification of GFAP and NT-proBNP in distinguishing ischemic and hemorrhagic stroke

The goal of this study is to create a highly sensitive time-resolved fluorescence lateral flow immunoassay (TRF-LFIA) capable of concurrently measuring glial fibrillary acidic protein (GFAP) and the N-terminal fragment of B-type natriuretic peptide precursor (NT-proBNP). This assay is designed as a diagnostic tool and aims to provide an algorithm for stroke management, specifically for distinguishing between Ischemic stroke (IS) and Hemorrhagic stroke (HS). However, LFIA to quantify simultaneous serum NT-proBNP and GFAP are not yet available. We have developed and validated a novel TRF-LFIA for the simultaneous quantitative detection of NT-proBNP and GFAP. The sensitivity and reproducibility of the immunoassay were significantly improved by employing specific monoclonal antibodies linked to europium nanoparticles (EuNPs) that specifically target NT-proBNP and GFAP. The detection area on the nitrocellulose membrane featured sandwich-style complexes containing two test lines for NT-proBNP and GFAP, and one Control line. The fluorescence intensity of these test lines and control line was measured using an in-house developed Exdia TRF-Plus analyzer. As proof-of-concept, we enrolled patients suspected of having a stroke who were admitted within a specific time frame (6 h). A small amount of clinical specimen (serum) was used. To optimize the LFIA, an EuNPs conjugated antibodies were investigated to improve the detection sensitivity and decrease the background signal as well shorten the detection time. The Exdia TRF-LFIA cartridge offers a wide linear dynamic detection range, rapid detection, high sensitivity, and specificity. The limit of detection was determined to be 98 pg/mL for NT-proBNP and 68 pg/mL for GFAP, with minimal cross-reactivity. There were 200 clinical human serum samples that were used to evaluate this platform with high correlation. By combining the results of NT-proBNP and GFAP, we formulated an algorithm for the clinical assessment of Ischemic Stroke (IS) and Hemorrhagic Stroke (HS). According to our proposed algorithm, the combination of GFAP and NT-proBNP emerged as the most effective biomarker combination for distinguishing between IS and HS. Exdia TRF-LFIA shows great potential as a supplemental method for in vitro diagnostics in the laboratory or in other point-of-care testing (POCT) applications. Its development substantially decreases the diagnosis time for IS and HS. The proposed algorithm not only minimizes treatment delays but also lowers medical costs for patients.

Impact of Direct Transport to Thrombectomy-Capable Center vs. Nearby/Distant Local Stroke Centers on Stroke Outcome in Patients Undergoing Thrombectomy: A Real-Life Study

Our aim was to compare the stroke outcomes of a direct transfer (DT) to a thrombectomy-capable center vs. initial care at two local stroke centers: a nearby hospital (NH, 36 km) and a distant hospital (DH, 113 km). Patients who underwent a mechanical thrombectomy were analyzed (February 2017-October 2021), and the outcome was considered favorable if the modified Rankin scale (mRS) score was ≤ 2 at three months. A total of 300 patients were included, 55 of which were transferred from the NH and 58 from the DH. There was a difference in the median (IQR) transfer time of 39 min between the hospitals (149 min for the NH vs. 188 min for the DH, p = 0.003). After adjusting for confounding variables, a secondary transfer from the DH, compared to a DT, was associated with a lower functional independence: mRS score ≤ 2 (OR = 0.37, 95% CI = 0.14-0.97, p = 0.043), without significant differences in the mortality between the groups. These differences were not observed in patients from the NH. Conclusions: A secondary transfer from a distant hospital was associated with a poorer functional outcome at 3 months. This unfavorable outcome was not observed among patients transferred from a nearby hospital. These findings highlight the importance of categorizing the suitability of one transfer model over another based on the proximity of hospitals to the thrombectomy center, but also in accordance with organizational and geographic characteristics that vary within each health region.

Basilar artery occlusion: drip-and-ship versus direct-to-center for mechanical thrombectomy within the Neurovascular Network of Southwest Bavaria (NEVAS)

BACKGROUND

Recent clinical trials revealed a substantial clinical benefit for mechanical thrombectomy (MT) in patients with basilar artery occlusion (BAO). While urban areas are sufficiently covered with comprehensive stroke centers and MT expertise, rural areas lack such resources. Structured telemedical stroke networks offer rural hospitals instant consultation by stroke experts, enabling swift administration of intravenous thrombolysis (IVT) on-site and transportation for MT. For BAO patients, data on performance and clinical outcomes in telemedical stroke networks are lacking.

METHODS

We retrospectively analyzed data from patients with acute BAO eligible for MT: those treated directly in our comprehensive stroke center (direct-to-center/DC) and those treated in rural hospitals that were telemedically consulted by the Neurovascular Network of Southwest Bavaria (NEVAS) and transferred to our center for MT (drip-and-ship, DS). Key time intervals, stroke management performance and functional outcome after 90 days were compared.

RESULTS

Baseline characteristics, including premorbid status and stroke severity, were comparable. Time from symptom onset to IVT was identical in both groups (118 min). There was a delay of 180 min until recanalization in DS patients, mainly due to patient transport for MT. Procedural treatment time intervals, success of recanalization and complications were comparable. Clinical outcome at 3 months follow-up of DS patients was not inferior to DC patients.

CONCLUSION

We show for the first time that patients with BAO in rural areas benefit from a structured telemedicine network such as NEVAS, regarding both on-site processing and drip-and-ship for MT. Clinical outcomes are comparable among DS and DC patients.

Cincinnati Prehospital Stroke Scale (CPSS) as a Screening Tool for Early Identification of Cerebral Large Vessel Occlusions; a Systematic Review and Meta-analysis

Introduction

Large vessel occlusion (LVO) strokes are associated with worse functional outcomes and higher mortality rates. In the present systematic review and meta-analysis, we evaluated the diagnostic yield of the Cincinnati Prehospital Stroke Scale (CPSS) in detecting LVO.

Methods

We performed an extensive systematic search among online databases including Medline, Embase, Web of Science, and Scopus, until July 31st, 2023. We also conducted a manual search on Google and Google scholar, along with citation tracking to supplement the systematic search in retrieving all studies that evaluated the diagnostic accuracy of the CPSS in detecting LVO among patients suspected to stroke.

Results

Fourteen studies were included in the present meta-analysis. CPSS showed the sensitivity of 97% (95% CI: 87%-99%) and the specificity of 17% (95% CI: 4%-54%) at the cut-off point of ≥1. The optimal threshold was determined to be ≥2, with a sensitivity of 82% (95% CI: 74%-88%) and specificity of 62% (95% CI: 48%-74%) in detecting LVO. At the highest cut-off point of ≥3, the CPSS had the lowest sensitivity of 60% (95% CI: 51%-69%) and the highest specificity of 81% (95% CI: 71%-88%). Sensitivity analyses showed the robustness of the results regardless of study population, inclusion of hemorrhagic stroke patients, pre-hospital or in-hospital settings, and the definition of LVO.

Conclusion

A very low level of evidence demonstrated that CPSS, with a threshold set at ≥2, is a useful tool for identifying LVO stroke and directing patients to CSCs, both in prehospital and in-hospital settings.

Portable cerebral blood flow monitor to detect large vessel occlusion in patients with suspected stroke

BACKGROUND

Early detection of large vessel occlusion (LVO) facilitates triage to an appropriate stroke center to reduce treatment times and improve outcomes. Prehospital stroke scales are not sufficiently sensitive, so we investigated the ability of the portable Openwater optical blood flow monitor to detect LVO.

METHODS

Patients were prospectively enrolled at two comprehensive stroke centers during stroke alert evaluation within 24 hours of onset with National Institutes of Health Stroke Scale (NIHSS) score ≥2. A 70 s bedside optical blood flow scan generated cerebral blood flow waveforms based on relative changes in speckle contrast. Anterior circulation LVO was determined by CT angiography. A deep learning model trained on all patient data using fivefold cross-validation and learned discriminative representations from the raw speckle contrast waveform data. Receiver operating characteristic (ROC) analysis compared the Openwater diagnostic performance (ie, LVO detection) with prehospital stroke scales.

RESULTS

Among 135 patients, 52 (39%) had an anterior circulation LVO. The median NIHSS score was 8 (IQR 4-14). The Openwater instrument had 79% sensitivity and 84% specificity for the detection of LVO. The rapid arterial occlusion evaluation (RACE) scale had 60% sensitivity and 81% specificity and the Los Angeles motor scale (LAMS) had 50% sensitivity and 81% specificity. The binary Openwater classification (high-likelihood vs low-likelihood) had an area under the ROC (AUROC) of 0.82 (95% CI 0.75 to 0.88), which outperformed RACE (AUC 0.70; 95% CI 0.62 to 0.78; P=0.04) and LAMS (AUC 0.65; 95% CI 0.57 to 0.73; P=0.002).

CONCLUSIONS

The Openwater optical blood flow monitor outperformed prehospital stroke scales for the detection of LVO in patients undergoing acute stroke evaluation in the emergency department. These encouraging findings need to be validated in an independent test set and the prehospital environment.

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.

Time to Treatment With Intravenous Thrombolysis Before Thrombectomy and Functional Outcomes in Acute Ischemic Stroke: A Meta-Analysis

Importance

The benefit of intravenous thrombolysis (IVT) for acute ischemic stroke declines with longer time from symptom onset, but it is not known whether a similar time dependency exists for IVT followed by thrombectomy.

Objective

To determine whether the benefit associated with IVT plus thrombectomy vs thrombectomy alone decreases with treatment time from symptom onset.

Design, Setting, and Participants

Individual participant data meta-analysis from 6 randomized clinical trials comparing IVT plus thrombectomy vs thrombectomy alone. Enrollment was between January 2017 and July 2021 at 190 sites in 15 countries. All participants were eligible for IVT and thrombectomy and presented directly at thrombectomy-capable stroke centers (n = 2334). For this meta-analysis, only patients with an anterior circulation large-vessel occlusion were included (n = 2313).

Exposure

Interval from stroke symptom onset to expected administration of IVT and treatment with IVT plus thrombectomy vs thrombectomy alone.

Main Outcomes and Measures

The primary outcome analysis tested whether the association between the allocated treatment (IVT plus thrombectomy vs thrombectomy alone) and disability at 90 days (7-level modified Rankin Scale [mRS] score range, 0 [no symptoms] to 6 [death]; minimal clinically important difference for the rates of mRS scores of 0-2: 1.3%) varied with times from symptom onset to expected administration of IVT.

Results

In 2313 participants (1160 in IVT plus thrombectomy group vs 1153 in thrombectomy alone group; median age, 71 [IQR, 62 to 78] years; 44.3% were female), the median time from symptom onset to expected administration of IVT was 2 hours 28 minutes (IQR, 1 hour 46 minutes to 3 hours 17 minutes). There was a statistically significant interaction between the time from symptom onset to expected administration of IVT and the association of allocated treatment with functional outcomes (ratio of adjusted common odds ratio [OR] per 1-hour delay, 0.84 [95% CI, 0.72 to 0.97], P = .02 for interaction). The benefit of IVT plus thrombectomy decreased with longer times from symptom onset to expected administration of IVT (adjusted common OR for a 1-step mRS score shift toward improvement, 1.49 [95% CI, 1.13 to 1.96] at 1 hour, 1.25 [95% CI, 1.04 to 1.49] at 2 hours, and 1.04 [95% CI, 0.88 to 1.23] at 3 hours). For a mRS score of 0, 1, or 2, the predicted absolute risk difference was 9% (95% CI, 3% to 16%) at 1 hour, 5% (95% CI, 1% to 9%) at 2 hours, and 1% (95% CI, -3% to 5%) at 3 hours. After 2 hours 20 minutes, the benefit associated with IVT plus thrombectomy was not statistically significant and the point estimate crossed the null association at 3 hours 14 minutes.

Conclusions and Relevance

In patients presenting at thrombectomy-capable stroke centers, the benefit associated with IVT plus thrombectomy vs thrombectomy alone was time dependent and statistically significant only if the time from symptom onset to expected administration of IVT was short.

Endovascular Thrombectomy Treatment Effect in Direct vs Transferred Patients With Large Ischemic Strokes: A Prespecified Analysis of the SELECT2 Trial

Importance

Patients with large ischemic core stroke have poor clinical outcomes and are frequently not considered for interfacility transfer for endovascular thrombectomy (EVT).

Objective

To assess EVT treatment effects in transferred vs directly presenting patients and to evaluate the association between transfer times and neuroimaging changes with EVT clinical outcomes.

Design, Setting, and Participants

This prespecified secondary analysis of the SELECT2 trial, which evaluated EVT vs medical management (MM) in patients with large ischemic stroke, evaluated adults aged 18 to 85 years with acute ischemic stroke due to occlusion of the internal carotid or middle cerebral artery (M1 segment) as well as an Alberta Stroke Program Early CT Score (ASPECTS) of 3 to 5, core of 50 mL or greater on imaging, or both. Patients were enrolled between October 2019 and September 2022 from 31 EVT-capable centers in the US, Canada, Europe, Australia, and New Zealand. Data were analyzed from August 2023 to January 2024.

Interventions

EVT vs MM.

Main Outcomes and Measures

Functional outcome, defined as modified Rankin Scale (mRS) score at 90 days with blinded adjudication.

Results

A total of 958 patients were screened and 606 patients were excluded. Of 352 enrolled patients, 145 (41.2%) were female, and the median (IQR) age was 66.5 (58-75) years. A total of 211 patients (59.9%) were transfers, while 141 (40.1%) presented directly. The median (IQR) transfer time was 178 (136-230) minutes. The median (IQR) ASPECTS decreased from the referring hospital (5 [4-7]) to an EVT-capable center (4 [3-5]). Thrombectomy treatment effect was observed in both directly presenting patients (adjusted generalized odds ratio [OR], 2.01; 95% CI, 1.42-2.86) and transferred patients (adjusted generalized OR, 1.50; 95% CI, 1.11-2.03) without heterogeneity (P for interaction = .14). Treatment effect point estimates favored EVT among 82 transferred patients with a referral hospital ASPECTS of 5 or less (44 received EVT; adjusted generalized OR, 1.52; 95% CI, 0.89-2.58). ASPECTS loss was associated with numerically worse EVT outcomes (adjusted generalized OR per 1-ASPECTS point loss, 0.89; 95% CI, 0.77-1.02). EVT treatment effect estimates were lower in patients with transfer times of 3 hours or more (adjusted generalized OR, 1.15; 95% CI, 0.73-1.80).

Conclusions and Relevance

Both directly presenting and transferred patients with large ischemic stroke in the SELECT2 trial benefited from EVT, including those with low ASPECTS at referring hospitals. However, the association of EVT with better functional outcomes was numerically better in patients presenting directly to EVT-capable centers. Prolonged transfer times and evolution of ischemic change were associated with worse EVT outcomes. These findings emphasize the need for rapid identification of patients suitable for transfer and expedited transport.

Trial Registration

ClinicalTrials.gov Identifier: NCT03876457.

Clinical outcome of rural in-hospital-stroke patients after interhospital transfer for endovascular therapy within a telemedical stroke network in Germany: a registry-based observational study

OBJECTIVES

Little is known about in-hospital-stroke (IHS) patients with large vessel occlusion and subsequent transfer to referral centres for endovascular therapy (EVT). However, this subgroup is highly relevant given the substantial amount of IHS, the ongoing trend towards greater use of EVT and lack of EVT possibilities in rural hospitals. The study objective is to explore the clinical outcomes of this vulnerable patient group, given that both IHS and interhospital transfer are associated with worse clinical outcomes due to a higher proportion of pre-existing conditions and substantial time delays during transfer.

DESIGN AND SETTING

Prospectively collected data of patients receiving EVT after interhospital transfer from 14 rural hospitals of the Telemedical Stroke Network in Southeast Bavaria (TEMPiS) between February 2018 and July 2020 was analysed.

PARTICIPANTS

49 IHS and 274 out-of-hospital-stroke (OHS) patients were included.

OUTCOME MEASURES

Baseline characteristics, treatment times and outcomes were compared between IHS and OHS. The primary endpoint was a 3-month modified Rankin Scale (mRS).

RESULTS

In IHS patients, atrial fibrillation (55.3% vs 35.9%, p=0.012), diabetes (36.2% vs 21.1%, p=0.024) and use of oral anticoagulants (44.7% vs 20.8%, p<0.001) were more frequent. Stroke severity was similar in both groups. Treatment times from symptom onset to first brain imaging, therapy decision or EVT were shorter for IHS patients. IHS patients displayed worse clinical outcomes: 59.2% of IHS patients died within 3 months compared with 28.5% of OHS patients (p<0.001). They were less likely to achieve moderate outcomes (mRS 0-3) 3 months after stroke (20.4% vs 39.8%, p=0.010). After controlling for possible confounding variables, IHS was associated with worse clinical outcomes (adjusted OR 3.04 (95% CI 1.57 to 6.04), p<0.001).

CONCLUSIONS

The mortality of IHS patients after interhospital transfer and EVT was high and functional outcomes were worse compared with those of OHS patients. Further research is needed to ascertain whether IHS patients benefit from this therapeutic approach. A more careful selection of IHS patients for transfer and means to enable faster treatment should be considered.

TRIAL REGISTRATION NUMBER

NCT04270513; Post-results.

Influence of vascular imaging acquisition at local stroke centers on workflows in the drip-n-ship model: a RACECAT post hoc analysis

BACKGROUND

The influence of vascular imaging acquisition on workflows at local stroke centers (LSCs) not capable of performing thrombectomy in patients with a suspected large vessel occlusion (LVO) stroke remains uncertain. We analyzed the impact of performing vascular imaging (VI+) or not (VI- at LSC arrival on variables related to workflows using data from the RACECAT Trial.

OBJECTIVE

To compare workflows at the LSC among patients enrolled in the RACECAT Trial with or without VI acquisition.

METHODS

We included patients with a diagnosis of ischemic stroke who were enrolled in the RACECAT Trial, a cluster-randomized trial that compared drip-n-ship versus mothership triage paradigms in patients with suspected acute LVO stroke allocated at the LSC. Outcome measures included time metrics related to workflows and the rate of interhospital transfers and thrombectomy among transferred patients.

RESULTS

Among 467 patients allocated to a LSC, vascular imaging was acquired in 277 patients (59%), of whom 198 (71%) had a LVO. As compared with patients without vascular imaging, patients in the VI+ group were transferred less frequently as thrombectomy candidates to a thrombectomy-capable center (58% vs 74%, P=0.004), without significant differences in door-indoor-out time at the LSC (median minutes, VI+ 78 (IQR 69-96) vs VI- 76 (IQR 59-98), P=0.6). Among transferred patients, the VI+ group had higher rate of thrombectomy (69% vs 55%, P=0.016) and shorter door to puncture time (median minutes, VI+ 41 (IQR 26-53) vs VI- 54 (IQR 40-70), P<0.001).

CONCLUSION

Among patients with a suspected LVO stroke initially evaluated at a LSC, vascular imaging acquisition might improve workflow times at thrombectomy-capable centers and reduce the rate of futile interhospital transfers. These results deserve further evaluation and should be replicated in other settings and geographies.

Effect of time delay in inter-hospital transfer on outcomes of endovascular treatment of acute ischemic stroke

Background

Endovascular treatment (EVT) with mechanical thrombectomy is the standard of care for large vessel occlusion (LVO) in acute ischemic stroke (AIS). The most common approach today is to perform EVT in a comprehensive stroke center (CSC) and transfer relevant patients for EVT from a primary stroke center (PSC). Rapid and efficient treatment of LVO is a key factor in achieving a good clinical outcome.

Methods

We present our retrospective cohort of patients who underwent EVT between 2018 and 2021, including direct admissions and patients transferred from PSC. Primary endpoints were time intervals (door-to-puncture, onset-to-puncture, door-to-door) and favorable outcome (mRS ≤ 2) at 90 days. Secondary outcomes were successful recanalization, mortality rate, and symptomatic intracranial hemorrhage (sICH). Additional analysis was performed for transferred patients not treated with EVT; endpoints were time intervals, favorable outcomes, and reason for exclusion of EVT.

Results

Among a total of 405 patients, 272 were admitted directly to our EVT center and 133 were transferred; there was no significant difference between groups in the occluded vascular territory, baseline NIHSS, wake-up strokes, or thrombolysis rate. Directly admitted patients had a shorter door-to-puncture time than transferred patients (190 min vs. 293 min, p < 0.001). The median door-to-door shift time was 204 min. We found no significant difference in functional independence, successful recanalization rates, or sICH rates. The most common reason to exclude transferred patients from EVT was clinical or angiographic improvement (55.6% of patients).

Conclusion

Our results show that transferring patients to the EVT center does not affect clinical outcomes, despite the expected delay in EVT. Reassessment of patients upon arrival at the CSC is crucial, and patient selection should be done based on both time and tissue window.

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.

Prehospital Detection of Large Vessel Occlusion Stroke With EEG

BACKGROUND AND OBJECTIVES

Endovascular thrombectomy (EVT) is standard treatment for anterior large vessel occlusion stroke (LVO-a stroke). Prehospital diagnosis of LVO-a stroke would reduce time to EVT by allowing direct transportation to an EVT-capable hospital. We aim to evaluate the diagnostic accuracy of dry electrode EEG for the detection of LVO-a stroke in the prehospital setting.

METHODS

ELECTRA-STROKE was an investigator-initiated, prospective, multicenter, diagnostic study, performed in the prehospital setting. Adult patients were eligible if they had suspected stroke (as assessed by the attending ambulance nurse) and symptom onset <24 hours. A single dry electrode EEG recording (8 electrodes) was performed by ambulance personnel. Primary endpoint was the diagnostic accuracy of the theta/alpha frequency ratio for LVO-a stroke (intracranial ICA, A1, M1, or proximal M2 occlusion) detection among patients with EEG data of sufficient quality, expressed as the area under the receiver operating characteristic curve (AUC). Secondary endpoints were diagnostic accuracies of other EEG features quantifying frequency band power and the pairwise derived Brain Symmetry Index. Neuroimaging was assessed by a neuroradiologist blinded to EEG results.

RESULTS

Between August 2020 and September 2022, 311 patients were included. The median EEG duration time was 151 (interquartile range [IQR] 151-152) seconds. For 212/311 (68%) patients, EEG data were of sufficient quality for analysis. The median age was 74 (IQR 66-81) years, 90/212 (42%) were women, and the median baseline NIH Stroke Scale was 1 (IQR 0-4). Six (3%) patients had an LVO-a stroke, 109/212 (51%) had a non-LVO-a ischemic stroke, 32/212 (15%) had a transient ischemic attack, 8/212 (4%) had a hemorrhagic stroke, and 57/212 (27%) had a stroke mimic. AUC of the theta/alpha ratio was 0.80 (95% CI 0.58-1.00). Of the secondary endpoints, the pairwise derived Brain Symmetry Index in the delta frequency band had the highest diagnostic accuracy (AUC 0.91 [95% CI 0.73-1.00], sensitivity 80% [95% CI 38%-96%], specificity 93% [95% CI 88%-96%], positive likelihood ratio 11.0 [95% CI 5.5-21.7]).

DISCUSSION

The data from this study suggest that dry electrode EEG has the potential to detect LVO-a stroke among patients with suspected stroke in the prehospital setting. Toward future implementation of EEG in prehospital stroke care, EEG data quality needs to be improved.

TRIAL REGISTRATION INFORMATION

ClinicalTrials.gov identifier: NCT03699397.

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that prehospital dry electrode scalp EEG accurately detects LVO-a stroke among patients with suspected acute stroke.

Distinct Alterations in Oxygenation, Ion Composition and Acid-Base Balance in Cerebral Collaterals During Large-Vessel Occlusion Stroke

PURPOSE

Disturbances of blood gas and ion homeostasis including regional hypoxia and massive sodium (Na+)/potassium (K+) shifts are a hallmark of experimental cerebral ischemia but have not been sufficiently investigated for their relevance in stroke patients.

METHODS

We report a prospective observational study on 366 stroke patients who underwent endovascular thrombectomy (EVT) for large-vessel occlusion (LVO) of the anterior circulation (18 December 2018-31 August 2020). Intraprocedural blood gas samples (1 ml) from within cerebral collateral arteries (ischemic) and matched systemic control samples were obtained according to a prespecified protocol in 51 patients.

RESULTS

We observed a significant reduction in cerebral oxygen partial pressure (-4.29%, paO2ischemic = 185.3 mm Hg vs. paO2systemic = 193.6 mm Hg; p = 0.035) and K+ concentrations (-5.49%, K+ischemic = 3.44 mmol/L vs. K+systemic = 3.64 mmol/L; p = 0.0083). The cerebral Na+:K+ ratio was significantly increased and negatively correlated with baseline tissue integrity (r = -0.32, p = 0.031). Correspondingly, cerebral Na+ concentrations were most strongly correlated with infarct progression after recanalization (r = 0.42, p = 0.0033). We found more alkaline cerebral pH values (+0.14%, pHischemic = 7.38 vs. pHsystemic = 7.37; p = 0.0019), with a time-dependent shift towards more acidotic conditions (r = -0.36, p = 0.055).

CONCLUSION

These findings suggest that stroke-induced changes in oxygen supply, ion composition and acid-base balance occur and dynamically progress within penumbral areas during human cerebral ischemia and are related to acute tissue damage.

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.

Advancing healthcare equity through dissemination and implementation science

OBJECTIVE

To provide guiding principles and recommendations for how approaches from the field of dissemination and implementation (D&I) science can advance healthcare equity.

DATA SOURCES AND STUDY SETTING

This article, part of a special issue sponsored by the Agency for Healthcare Research and Quality (AHRQ), is based on an outline drafted to support proceedings of the 2022 AHRQ Health Equity Summit and further revised to reflect input from Summit attendees.

STUDY DESIGN

This is a narrative review of the current and potential applications of D&I approaches for understanding and advancing healthcare equity, followed by discussion and feedback with Summit attendees.

DATA COLLECTION/EXTRACTION METHODS

We identified major themes in narrative and systematic reviews related to D&I science, healthcare equity, and their intersections. Based on our expertise, and supported by synthesis of published studies, we propose recommendations for how D&I science is relevant for advancing healthcare equity. We used iterative discussions internally and at the Summit to refine preliminary findings and recommendations.

PRINCIPAL FINDINGS

We identified four guiding principles and three D&I science domains with strong promise for accelerating progress toward healthcare equity. We present eight recommendations and more than 60 opportunities for action by practitioners, healthcare leaders, policy makers, and researchers.

CONCLUSIONS

Promising areas for D&I science to impact healthcare equity include the following: attention to equity in the development and delivery of evidence-based interventions; the science of adaptation; de-implementation of low-value care; monitoring equity markers; organizational policies for healthcare equity; improving the economic evaluation of implementation; policy and dissemination research; and capacity building.

Subhairline Electroencephalography for the Detection of Large Vessel Occlusion Stroke

BACKGROUND

Endovascular thrombectomy is standard treatment for patients with anterior circulation large vessel occlusion stroke (LVO-a). Prehospital identification of these patients would enable direct routing to an endovascular thrombectomy-capable hospital and consequently reduce time-to-endovascular thrombectomy. Electroencephalography (EEG) has previously proven to be promising for LVO-a stroke detection. Fast and reliable electrode application, however, can remain a challenge. A potential alternative is subhairline EEG. We evaluated the diagnostic accuracy of subhairline EEG for LVO-a stroke detection.

METHODS AND RESULTS

We included adult patients with a suspected stroke or known LVO-a stroke and symptom onset time <24 hours. A single 3-minute EEG recording was performed at the emergency department, before endovascular thrombectomy, using 9 self-adhesive electrodes placed on the forehead and behind the ears. We evaluated the diagnostic accuracies of EEG features quantifying frequency band power and brain symmetry (pairwise derived Brain Symmetry Index) for LVO-a stroke detection using receiver operating characteristic analysis. EEG data were of sufficient quality for analysis in 51/52 (98%) included patients. Of these patients, 16 (31%) had an LVO-a stroke, 16 (31%) a non-LVO-a ischemic stroke, 5 (10%) a transient ischemic attack, and 14 (27%) a stroke mimic. Median symptom-onset-to-EEG-time was 266 (interquartile range 130-709) minutes. The highest diagnostic accuracy for LVO-a stroke detection was reached by the pairwise derived Brain Symmetry Index in the theta frequency band (area under the receiver operating characteristic curve 0.90; sensitivity 86%; specificity 83%).

CONCLUSIONS

Subhairline EEG could detect LVO-a stroke with high diagnostic accuracy and had high data reliability. These data suggest that subhairline EEG is potentially suitable as a prehospital stroke triage instrument.

Associations between emergency call stroke triage and pre-hospital delay, primary hospital admission, and acute reperfusion treatment among early comers with acute ischemic stroke

To investigate the association between the Emergency Medical Service dispatcher's initial stroke triage and prehospital stroke management, primary admission to hospitals offering revascularization treatment, prehospital time delay, and rate of acute revascularization. In an observational cohort study, patients with acute ischemic stroke (AIS) in Denmark (2017-2018) were included if the emergency call to the Emergency Medical Dispatch Center (EMDC) was made within three hours after symptom onset. Among 3546 included AIS patients, the EMS dispatcher identified 74.6% (95% confidence interval (CI) 73.1-76.0) correctly as stroke. EMS dispatcher stroke recognition was associated with a higher rate of primary admission to a hospital offering revascularization treatment (85.8 versus 74.5%); producing an adjusted risk difference (RD) of 11.1% (95% CI 7.8; 14.3) and a higher rate of revascularization treatment (49.6 versus 41.6%) with an adjusted RD of 8.4% (95% CI 4.6; 12.2). We adjusted for sex, age, previous stroke or transient ischemic attack, and stroke severity. EMDC stroke recognition was associated with shorter prehospital delay. For all AIS patients, the adjusted difference was - 33.2 min (95% CI - 44.4; - 22.0). Among patients receiving acute revascularization treatment (n = 1687), the adjusted difference was -12.6 min (95% CI - 18.9; - 6.3). Stroke recognition by the EMS dispatcher was associated with a higher probability of primary admission to a hospital offering acute stroke treatment, and subsequently with a higher rate of acute revascularization treatment, and with an overall reduction in prehospital delay.

Geographical Requirements for the Applicability of the Results of the RACECAT Study to Other Stroke Networks

Background The RACECAT (Transfer to the Closest Local Stroke Center vs Direct Transfer to Endovascular Stroke Center of Acute Stroke Patients With Suspected Large Vessel Occlusion in the Catalan Territory) trial was the first randomized trial addressing the prehospital triage of acute stroke patients based on the distribution of thrombolysis centers and intervention centers in Catalonia, Spain. The study compared the drip-and-ship with the mothership paradigm in regions where a local thrombolysis center can be reached faster than the nearest intervention center (equipoise region). The present study aims to determine the population-based applicability of the results of the RACECAT study to 4 stroke networks with a different degree of clustering of the intervention centers (clustered, dispersed). Methods and Results Stroke networks were compared with regard to transport time saved for thrombolysis (under the drip-and-ship approach) and transport time saved for endovascular therapy (under the mothership approach). Population-based transport times were modeled with a local instance of an openrouteservice server using open data from OpenStreetMap.The fraction of the population in the equipoise region differed substantially between clustered networks (Catalonia, 63.4%; France North, 87.7%) and dispersed networks (Southwest Bavaria, 40.1%; Switzerland, 40.0%). Transport time savings for thrombolysis under the drip-and-ship approach were more marked in clustered networks (Catalonia, 29 minutes; France North, 27 minutes) than in dispersed networks (Southwest Bavaria and Switzerland, both 18 minutes). Conclusions Infrastructure differences between stroke networks may hamper the applicability of the results of the RACECAT study to other stroke networks with a different distribution of intervention centers. Stroke networks should assess the population densities and hospital type/distribution in the temporal domain before applying prehospital triage algorithms to their specific setting.

Modern Prehospital Screening Technology for Emergent Neurovascular Disorders

Stroke is a serious neurological disease and a significant contributor to disability worldwide. Traditional in-hospital imaging techniques such as computed tomography (CT) and magnetic resonance imaging (MRI) remain the standard modalities for diagnosing stroke. The development of prehospital stroke detection devices may facilitate earlier diagnosis, initiation of stroke care, and ultimately better patient outcomes. In this review, the authors summarize the features of eight stroke detection devices using noninvasive brain scanning technology. The review summarizes the features of stroke detection devices including portable CT, MRI, transcranial Doppler ultrasound , microwave tomographic imaging, electroencephalography, near-infrared spectroscopy, volumetric impedance phaseshift spectroscopy, and cranial accelerometry. The technologies utilized, the indications for application, the environments indicated for application, the physical features of the eight stroke detection devices, and current commercial products are discussed. As technology advances, multiple portable stroke detection instruments exhibit the promising potential to expedite the diagnosis of stroke and enhance the time taken for treatment, ultimately aiding in prehospital stroke triage.

Identification of Novel Circular RNA Targets in Key Penumbra Region of Rats After Cerebral Ischemia-Reperfusion Injury

Circular RNAs (circRNAs) are abundantly and stably expressed in the brain of mammals and humans. Some circRNAs are implicated in ischemic stroke. Therefore, we aimed to detect how circRNAs change in the key penumbra area during cerebral ischemia-reperfusion (CI/R) injury. Rats were subjected to transient middle cerebral artery occlusion (tMCAO), during which the permanent blocking period was 2 h and reperfusion time was 24 or 72 h. Then modified neurologic severity score (mNSS), triphenyl tetrazolium chloride (TTC) staining and HE staining were used to exhibiting damage between rats in different groups. The penumbra regions of all rats were dissected and total RNA was further processed for high-throughput sequencing. CircRNA expression profiles were screened and bioinformatics analyses were conducted to investigate these differentially expressed circRNAs. Some of them were verified by reverse transcription-quantitative polymerase chain reaction (RT-qPCR), followed by the establishment of a circRNA-miRNA-mRNA network and the detection of their downstream molecules. A total of 99 and 98 circRNAs were differentially expressed at CI/R 24 h and CI/R 72 h, respectively. Notably, 21 circRNAs significantly changed at both reperfusion points. Three circRNAs, namely circ.7225, circ.5415, and circ.20623 were found to be associated with CI/R injury and might be preferred targets. Common downstream miR-298-5p and Bcl-3 were found to make up the circRNA-miRNA-mRNA network. Novel circRNA targets came to light in the penumbra of rats during CI/R injury and might establish the circRNA-miRNA-mRNA relationship, thus serving as potential biomarkers for ischemic stroke treatment.

Correlation between EEG spectral power and cerebral perfusion in patients with acute ischemic stroke

Dry electrode electroencephalography (EEG) has the potential to diagnose ischemic stroke in the acute phase. In the current study we determined the correlation between EEG spectral power and ischemic stroke size and location as determined by computed tomography perfusion (CTP). Dry electrode EEG recordings were performed in patients with acute ischemic stroke in the emergency room. CTP preceded the EEG recordings as part of standard imaging protocol. Infarct core volume, total hypoperfused volume and local cerebral blood flow (CBF) were estimated with CTP. Additionally, global and local EEG spectral power were determined. We used Spearman's correlation coefficients to evaluate the correlation between variables. We included 27 patients (median age 72 [IQR:69-80] years, 15/27 [56%] men). Median CTP-to-EEG time was 32 (range:8-138) minutes. Hypoperfused volumes were estimated for 12/27 (44%) patients. Infarct core volume correlated best with global delta power (ρ = 0.76, p < 0.01), total hypoperfused volume with global alpha power (ρ = -0.58, p = 0.05), and local CBF with local alpha power (ρ = 0.43, p < 0.01). We conclude that dry electrode EEG signals slow down with increasing hypoperfused volume, which could potentially be used to discriminate between small and large ischemic strokes.

Higher Procedural Volumes Are Associated with Faster Treatment Times, Better Functional Outcomes, and Lower Mortality in Patients Undergoing Endovascular Treatment for Acute Ischemic Stroke

OBJECTIVE

We aimed to characterize the association of hospital procedural volumes with outcomes among acute ischemic stroke (AIS) patients undergoing endovascular therapy (EVT).

METHODS

This was a retrospective, observational cohort study using data prospectively collected from January 1, 2016 to December 31, 2019 in the Get with the Guidelines-Stroke registry. Participants were derived from a cohort of 60,727 AIS patients treated with EVT within 24 hours at 626 hospitals. The primary cohort excluded patients with pretreatment National Institutes of Health Stroke Scale (NIHSS) < 6, onset-to-treatment time > 6 hours, and interhospital transfers. There were 2 secondary cohorts: (1) the EVT metrics cohort excluded patients with missing data on time from door to arterial puncture and (2) the intravenous thrombolysis (IVT) metrics cohort only included patients receiving IVT ≤4.5 hours after onset.

RESULTS

The primary cohort (mean ± standard deviation age = 70.7 ± 14.8 years; 51.2% female; median [interquartile range] baseline NIHSS = 18.0 [13-22]; IVT use, 70.2%) comprised 21,209 patients across 595 hospitals. The EVT metrics cohort and IVT metrics cohort comprised 47,262 and 16,889 patients across 408 and 601 hospitals, respectively. Higher procedural volumes were significantly associated with higher odds (expressed as adjusted odds ratio [95% confidence interval] for every 10-case increase in volume) of discharge to home (1.03 [1.02-1.04]), functional independence at discharge (1.02 [1.01-1.04]), and lower rates of in-hospital mortality (0.96 [0.95-0.98]). All secondary measures were also associated with procedural volumes.

INTERPRETATION

Among AIS patients primarily presenting to EVT-capable hospitals (excluding those transferred from one facility to another and those suffering in-hospital strokes), EVT at hospitals with higher procedural volumes was associated with faster treatment times, better discharge outcomes, and lower rates of in-hospital mortality. ANN NEUROL 2023.

Value of intravenous thrombolysis in endovascular treatment for large-vessel anterior circulation stroke: individual participant data meta-analysis of six randomised trials

BACKGROUND

Intravenous thrombolysis is recommended before endovascular treatment, but its value has been questioned in patients who are admitted directly to centres capable of endovascular treatment. Existing randomised controlled trials have indicated non-inferiority of endovascular treatment alone or have been statistically inconclusive. We formed the Improving Reperfusion Strategies in Acute Ischaemic Stroke collaboration to assess non-inferiority of endovascular treatment alone versus intravenous thrombolysis plus endovascular treatment.

METHODS

We conducted a systematic review and individual participant data meta-analysis to establish non-inferiority of endovascular treatment alone versus intravenous thrombolysis plus endovascular treatment. We searched PubMed and MEDLINE with the terms "stroke", "endovascular treatment", "intravenous thrombolysis", and synonyms for articles published from database inception to March 9, 2023. We included randomised controlled trials on the topic of interest, without language restrictions. Authors of the identified trials agreed to take part, and individual participant data were provided by the principal investigators of the respective trials and collated centrally by the collaborators. Our primary outcome was the 90-day modified Rankin Scale (mRS) score. Non-inferiority of endovascular treatment alone was assessed using a lower boundary of 0·82 for the 95% CI around the adjusted common odds ratio (acOR) for shift towards improved outcome (analogous to 5% absolute difference in functional independence) with ordinal regression. We used mixed-effects models for all analyses. This study is registered with PROSPERO, CRD42023411986.

FINDINGS

We identified 1081 studies, and six studies (n=2313; 1153 participants randomly assigned to receive endovascular treatment alone and 1160 randomly assigned to receive intravenous thrombolysis and endovascular treatment) were eligible for analysis. The risk of bias of the included studies was low to moderate. Variability between studies was small, and mainly related to the choice and dose of the thrombolytic drug and country of execution. The median mRS score at 90 days was 3 (IQR 1-5) for participants who received endovascular treatment alone and 2 (1-4) for participants who received intravenous thrombolysis plus endovascular treatment (acOR 0·89, 95% CI 0·76-1·04). Any intracranial haemorrhage (0·82, 0·68-0·99) occurred less frequently with endovascular treatment alone than with intravenous thrombolysis plus endovascular treatment. Symptomatic intracranial haemorrhage and mortality rates did not differ significantly.

INTERPRETATION

We did not establish non-inferiority of endovascular treatment alone compared with intravenous thrombolysis plus endovascular treatment in patients presenting directly at endovascular treatment centres. Further research could focus on cost-effectiveness analysis and on individualised decisions when patient characteristics, medication shortages, or delays are expected to offset a potential benefit of administering intravenous thrombolysis before endovascular treatment.

FUNDING

Stryker and Amsterdam University Medical Centers, University of Amsterdam.

Determinants of door-in-door-out time in patients with ischaemic stroke transferred for endovascular thrombectomy

BACKGROUND

Long door-in-door-out (DIDO) times are an important cause of treatment delay in patients transferred for endovascular thrombectomy (EVT) from primary stroke centres (PSC) to an intervention centre. Insight in causes of prolonged DIDO times may facilitate process improvement interventions. We aimed to quantify different components of DIDO time and to identify determinants of DIDO time.

METHODS

We performed a retrospective cohort study in a Dutch ambulance region consisting of six PSCs and one intervention centre. We included consecutive adult patients with anterior circulation large vessel occlusion, transferred from a PSC for EVT between October 1, 2019 and November 31, 2020. We subdivided DIDO into several time components and quantified contribution of these components to DIDO time. We used univariable and multivariable linear regression models to explore associations between potential determinants and DIDO time.

RESULTS

We included 133 patients. Median (IQR) DIDO time was 66 (52-83) min. The longest component was CTA-to-ambulance notification time with a median (IQR) of 24 (16-37) min. DIDO time increased with age (6 min per 10 years, 95% CI: 2-9), onset-to-door time outside 6 h (20 min, 95% CI: 5-35), M2-segment occlusion (15 min, 95% CI: 4-26) and right-sided ischaemia (12 min, 95% CI: 2-21).

CONCLUSIONS

The CTA-to-ambulance notification time is the largest contributor to DIDO time. Higher age, onset-to-door time longer than 6 h, M2-segment occlusion and right-sided occlusions are independently associated with a longer DIDO time. Future interventions that aim to decrease DIDO time should take these findings into account.

Long-term effect of field triage on times to endovascular treatment for emergent large vessel occlusion

BACKGROUND

Delays to endovascular therapy (EVT) for stroke may be mitigated with direct field triage to EVT centers. We sought to compare times to treatment over a 5.5 year span between two adjacent states, one with field triage and one without, served by a single comprehensive stroke center (CSC).

METHODS

During the study period, one of the two states implemented severity-based triage for suspected emergent large vessel occlusion, while in the other state, patients were transported to the closest hospital regardless of severity. We compared times to treatment and clinical outcomes between these two states. We also performed a matched pairs analysis, matching on date treated and distance from field to CSC.

RESULTS

639 patients met the inclusion criteria, 407 in State 1 (with field triage) and 232 in State 2 (without field triage). In State 1, scene to EVT decreased 6% (or 8.13 min, p=0.0004) every year but no decrease was observed for State 2 (<1%, p=0.94). Cumulatively over 5.5 years, there was a reduction of 43 min in time to EVT in State 1, but no change in State 2. Lower rates of disability were seen in State 1, both for the entire cohort (all OR 1.22, 95% CI 1.07 to 1.40, p=0.0032) and for those independent at baseline (1.36, 95% CI 1.15 to 1.59, p=0.0003).

CONCLUSIONS

Comparing adjacent states over time, the implementation of severity-based field triage significantly reduced time to EVT.

Clinical outcomes after endovascular thrombectomy in different triage methods

Objective

The purpose of this study was to evaluate the effectiveness and safety of drip and ship (DS) for acute ischemic stroke (AIS) by comparing three treatment strategies: 1) patients seen at a primary stroke center, started on emergency intravenous thrombolysis and then transported to a comprehensive stroke center (drip and ship, DS); 2) patients immediately transferred to comprehensive stroke center without starting intravenous thrombolysis, for mechanical thrombectomy (non-drip and ship, non-DS); and 3) patients admitted directly to the comprehensive stroke center for assessment and subsequent bridging thrombolysis (mothership, MS).

Methods

We retrospectively reviewed the data of patients that underwent mechanical thrombectomy for AIS from November 2020 to May 2022 at our institution. Patients were divided into three groups: DS, non-DS, and MS. Time course, multimodal CT features and clinical results were compared among the three groups.

Results

The study included 62 patients, with 19, 18, and 25 patients in DS, non-DS, and MS groups, respectively. Baseline characteristics did not differ among the three groups. The DS group had a significantly longer median onset to groin time than the MS group (395 min vs 244 min; P < 0.001), a significantly shorter onset to primary stroke center time than the non-DS group (90 min vs 463 min; P < 0.001), and a longer primary stroke center to groin puncture time than the non-DS group (277 min vs 162 min; P = 0.002). The onset to needle time was longer in the MS group than the DS group (151.2 min vs 111.8 min; P = 0.041). The intravenous thrombolysis to puncture time was shorter in the MS group compared with DS (56 min vs 278 min; P < 0.001). No significant differences were present among groups in post-operative variables measured.

Conclusions

DS is a safe and effective method, with no increased risk of postoperative complications or death compared to non-DS and MS methods. The study provides a reference for the selection of transport modes for AIS patients.

Simulation modelling to study the impact of adding comprehensive stroke centres. Can we deliver endovascular thrombectomy sooner?

OBJECTIVES

Regional accessibility and distribution of endovascular thrombectomy (EVT) capable facilities, that is, comprehensive stroke centres (CSCs), may significantly influence time to treatment. We analysed the impact of adding CSCs in the north of the Netherlands, a region with roughly 1.7 million inhabitants currently served by one CSC and eight primary stroke centres (PSCs).

DESIGN

Monte Carlo simulation modelling was used to establish new CSCs in our region by hypothetically upgrading existing PSCs to CSCs and ensuing adjustments in health services set-up.

SETTING

One CSC and eight PSCs in the north of the Netherlands.

PARTICIPANTS

165 patients with acute stroke treated with EVT and underwent interhospital transfer between PSC and CSC (drip and ship patients).

PRIMARY AND SECONDARY OUTCOMES

Time from onset to groin (OTG) puncture and predicted probability of favourable outcome (modified Rankin Scale 0-2) after 90 days. Sensitivity analyses were performed to assess uncertainty in workflow efficiency of CSCs.

RESULTS

Adding one or two CSCs would reduce the OTG time up to approximately 17 min and increases the predicted probability of favourable outcome by approximately 2%. Sensitivity analyses revealed that 'slow-acting' CSCs may reduce OTG by 3-5 min compared with 24-32 min for 'fast-acting' CSCs.

CONCLUSIONS

This study suggests that adding one or two CSCs in the north of the Netherlands would have modest impact. Improving workflow efficiencies seems to be more potent when aiming to improve existing acute stroke care systems.

'Drive the doctor' for endovascular thrombectomy in a rural area: a simulation study

BACKGROUND

Patients who present in a primary stroke center (PSC) with ischemic stroke are usually transferred to a comprehensive stroke center (CSC) in case of a large vessel occlusion (LVO) for endovascular thrombectomy (EVT) treatment, the so-called 'drip-and-ship' (DS) model. The 'drive-the-doctor' (DD) model modifies the DS model by allowing mobile interventionalists (MIs) to transfer to an upgraded PSC acting as a thrombectomy capable stroke center (TSC), instead of transferring patients to a CSC. Using simulation we estimated time savings and impact on clinical outcome of DD in a rural region.

METHODS

Data from EVT patients in northern Netherlands was prospectively collected in the MR CLEAN Registry between July 2014 - November 2017. A Monte Carlo simulation model of DS patients served as baseline model. Scenarios included regional spread of TSCs, pre-hospital patient routing to 'the nearest PSC' or 'nearest TSC', MI's notification after LVO confirmation or earlier prehospital, and MI's transport modalities. Primary outcomes are onset to groin puncture (OTG) and predicted probability of favorable outcome (PPFO) (mRS 0-2).

RESULTS

Combining all scenarios OTG would be reduced by 28-58 min and PPFO would be increased by 3.4-7.1%. Best performing and acceptable scenario was a combination of 3 TSCs, prehospital patient routing based on the RACE scale, MI notification after LVO confirmation and MI's transfer by ambulance. OTG would reduce by 48 min and PPFO would increase by 5.9%.

CONCLUSIONS

A DD model is a feasible scenario to optimize acute stroke services for EVT eligible patients in rural regions. Key design decisions in implementing the DD model for a specific region are regional spread of TSCs, patient routing strategy, and MI's notification moment and transport modality.

Women With Large Vessel Occlusion Acute Ischemic Stroke Are Less Likely to Be Routed to Comprehensive Stroke Centers

Background Prehospital routing of patients with large vessel occlusion (LVO) acute ischemic stroke (AIS) to centers capable of performing endovascular therapy may improve clinical outcomes. Here, we explore whether distance to comprehensive stroke centers (CSCs), stroke severity, and sex are associated with direct-to-CSC prehospital routing in patients with LVO AIS. Methods and Results In this cross-sectional study, we identified consecutive patients with LVO AIS from a prospectively collected multihospital registry throughout the greater Houston area from January 2019 to June 2020. Primary outcome was prehospital routing to CSC and was compared between men and women using modified Poisson regression including age, sex, race or ethnicity, first in-hospital National Institutes of Health Stroke Scale score, travel time, and distances to the closest primary stroke center and CSC. Among 503 patients with LVO AIS, 413 (82%) were routed to CSCs, and women comprised 46% of the study participants. Women with LVO AIS compared with men were older (73 versus 65, P<0.01) and presented with greater National Institutes of Health Stroke Scale score (14 versus 12, P=0.01). In modified Poisson regression, women were 9% less likely to be routed to CSCs compared with men (adjusted relative risk [aRR], 0.91 [0.84-0.99], P=0.024) and distance to nearest CSC ≤10 miles was associated with 38% increased chance of routing to CSC (aRR, 1.38 [1.26-1.52], P<0.001). Conclusions Despite presenting with more significant stroke syndromes and living within comparable distance to CSCs, women with LVO AIS were less likely to be routed to CSCs compared with men. Further study of the mechanisms behind this disparity is needed.

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: Stroke Outcomes Per Hospital Certification Status

Background

The thrombectomy-capable stroke center (TSC) is a recently introduced intermediate tier of accreditation for hospitals caring for patients with acute ischemic stroke (AIS). The comparative quality and clinical outcomes of reperfusion therapies at TSCs, primary stroke centers (PSCs), and comprehensive stroke centers (CSCs) has not been well delineated.

Methods

We conducted a retrospective, observational, cohort study from 2018-2020 that included patients with AIS who received endovascular (EVT) and/or intravenous (IVT) reperfusion therapies at CSC, TSC, or PSC. Participants were recruited from Get With The Guidelines-Stroke registry. Study endpoints included timeliness of IVT and EVT, successful reperfusion, discharge destination, discharge mortality, and functional independence at discharge.

Results

Among 84,903 included 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 NIHSS, longer onset-to-arrival time, and higher transfer-in rates for CSC/TSC/PSC, respectively. In adjusted analyses, the likelihood of achieving the goal door-to-needle time was higher in CSCs compared to PSCs (OR 1.39; 95% CI 1.17-1.66) and in TSCs compared to PSCs (OR 1.45; 95% CI 1.08-1.96). Similarly, the odds of achieving the goal door-to-puncture time were higher in CSCs compared to PSCs (OR 1.58; 95% CI 1.13-2.21). CSCs and TSCs also demonstrated better clinical efficacy outcomes compared to PSCs. The odds of discharge to home or rehabilitation were higher in CSCs compared to PSCs (OR 1.18; 95% CI 1.06-1.31), while the odds of in-hospital mortality/discharge to hospice were lower in both CSCs compared to PSCs (OR 0.87; 95% CI 0.81-0.94) and TSCs compared to 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 similar performance. Considering that over one-fifth of all EVT procedures during the study period were conducted at PSCs, it may be desirable to explore national initiatives aimed at facilitating the elevation of eligible PSCs to a higher certification status.

A Spatial Variation Analysis of In-Hospital Stroke Mortality Based on Integrated Pre-Hospital and Hospital Data in Mashhad, Iran

BACKGROUND

Despite significant advances in the quality and delivery of specialized stroke care, there still persist remarkable spatial variations in emergency medical services (EMS) transport delays, stroke incidence, and its outcomes. Therefore, it is very important to investigate the possible geographical variations of in-hospital stroke mortality and to identify its associated factors.

METHODS

This historical cohort study included suspected stroke cases transferred to Ghaem Hospital of Mashhad by the EMS from March 2018 to March 2019. Using emergency mission IDs, the pre-hospital emergency data were integrated with the patient medical records in the hospital. We used the Bayesian approach for estimating the model parameters.

RESULTS

Out of 301 patients (142 (47.2%) females vs. 159 (52.8%) males) with a final diagnosis of stroke, 61 (20.3%) cases had in-hospital mortality. Results from Bayesian spatial log-logistic proportional odds (PO) model showed that age (PO=1.07), access rate to EMS (PO=0.78), arrival time (evening shift vs. day shift, PO=0.09), and sequelae variables (PO=9.20) had a significant association with the odds of in-hospital stroke mortality (P<0.05). Furthermore, the odds of in-hospital stroke mortality were higher in central urban areas compared to suburban areas.

CONCLUSION

Marked regional variations were found in the odds of in-hospital stroke mortality in Mashhad. There was a direct association between age and odds of in-hospital stroke mortality. Hence, the prognosis of in-hospital stroke mortality could be improved by better control of hypertension, prevention of the occurrence of sequelae, increasing the access rate to EMS, and optimizing shift work schedule.

Mechanical thrombectomy combined with intravenous thrombolysis for acute ischemic stroke: a systematic review and meta-analyses

To assess the clinical value of mechanical thrombectomy (MT) combined with intravenous thrombolysis (IVT) in acute ischemic stroke (AIS) by comparing it with the MT alone. In this study, we conducted a comprehensive meta-analysis of both observational and randomized controlled studies (RCTs) to investigate various outcomes. Our search for relevant studies was conducted between January 2011 and June 2022 in four major databases: PubMed, Embase, WOS, and Cochrane Library. We collected data on several outcomes, including functional independence (FI; defined as modified Rankin Scale score of 0 to 2), excellent outcomes (mRS 0-1), successful recanalization (SR), symptomatic intracerebral hemorrhage (sICH), any intracerebral hemorrhage (aICH), and mortality at three months or discharge. The primary efficacy outcome and safety outcome were FI and sICH, respectively, whereas excellent outcomes and SR were considered secondary efficacy outcomes. Additionally, mortality and aICH were analyzed as secondary safety outcomes. We employed the Mantel-Haenszel fixed-effects model for RCTs when I² < 50%, otherwise the random-effects model was utilized. For observational studies and subgroup analyses, we used the random-effects model to minimize potential bias. A total of 55 eligible studies (nine RCTs and 46 observational studies) were included. For RCTs, the MT + IVT group was superior in FI (OR: 1.27, 95% CI: 1.11-1.46), excellent outcomes (OR: 1.21, 95% CI: 1.03-1.43), SR (OR: 1.23, 95% CI: 1.05-1.45), mortality (OR: 0.72, 95% CI: 0.54-0.97) in crude analyses. In adjusted analyses, the MT + IVT group reduced the risk of mortality (OR: 0.65, 95% CI: 0.49-0.88). However, the difference in FI between the MT + IVT group and the MT alone group was not significant (OR: 1.17, 95% CI: 0.99-1.38, Fig. 3a). For observational studies, the results of FI (OR: 1.34, 95% CI: 1.16-1.33), excellent outcomes (OR: 1.30, 95% CI: 1.09-1.54), SR (OR: 1.23, 95% CI: 1.05-1.44), mortality (OR: 0.70, 95% CI: 0.64-0.77) in the MT + IVT group were better. Additionally, the MT + IVT group increased the risk of hemorrhagic transformation (HT) including sICH (OR: 1.16, 95% CI: 1.11-1.21) and aICH (OR: 1.24, 95% CI: 1.05-1.46) in crude analyses. In adjusted analyses, significant better outcomes were seen in the MT + IVT group on FI (OR: 1.36, 95% CI: 1.21-1.52), excellent outcomes (OR: 1.49, 95% CI: 1.26-1.75), and mortality (OR: 0.73, 95% CI: 0.56-0.94). The MT + IVT therapy did improve the prognosis for AIS patients and did not increase the risk of HT compared with MT alone therapy.

Association Between Intravenous Thrombolysis and Clinical Outcomes Among Patients With Ischemic Stroke and Unsuccessful Mechanical Reperfusion

Importance

Clinical evidence of the potential treatment benefit of intravenous thrombolysis preceding unsuccessful mechanical thrombectomy (MT) is scarce.

Objective

To determine whether intravenous thrombolysis (IVT) prior to unsuccessful MT improves functional outcomes in patients with acute ischemic stroke.

Design, Setting, and Participants

Patients were enrolled in this retrospective cohort study from the prospective, observational, multicenter German Stroke Registry-Endovascular Treatment between May 1, 2015, and December 31, 2021. This study compared IVT plus MT vs MT alone in patients with acute ischemic stroke due to anterior circulation large-vessel occlusion in whom mechanical reperfusion was unsuccessful. Unsuccessful mechanical reperfusion was defined as failed (final modified Thrombolysis in Cerebral Infarction grade of 0 or 1) or partial (grade 2a). Patients meeting the inclusion criteria were matched by treatment group using 1:1 propensity score matching.

Interventions

Mechanical thrombectomy with or without IVT.

Main Outcomes and Measures

Primary outcome was functional independence at 90 days, defined as a modified Rankin Scale score of 0 to 2. Safety outcomes were the occurrence of symptomatic intracranial hemorrhage and death.

Results

After matching, 746 patients were compared by treatment arms (median age, 78 [IQR, 68-84] years; 438 women [58.7%]). The proportion of patients who were functionally independent at 90 days was 68 of 373 (18.2%) in the IVT plus MT and 42 of 373 (11.3%) in the MT alone group (adjusted odds ratio [AOR], 2.63 [95% CI, 1.41-5.11]; P = .003). There was a shift toward better functional outcomes on the modified Rankin Scale favoring IVT plus MT (adjusted common OR, 1.98 [95% CI, 1.35-2.92]; P < .001). The treatment benefit of IVT was greater in patients with partial reperfusion compared with failed reperfusion. There was no difference in symptomatic intracranial hemorrhages between treatment groups (AOR, 0.71 [95% CI, 0.29-1.81]; P = .45), while the death rate was lower after IVT plus MT (AOR, 0.54 [95% CI, 0.34-0.86]; P = .01).

Conclusions and Relevance

These findings suggest that prior IVT was safe and improved functional outcomes at 90 days. Partial reperfusion was associated with a greater treatment benefit of IVT, indicating a positive interaction between IVT and MT. These results support current guidelines that all eligible patients with stroke should receive IVT before MT and add a new perspective to the debate on noninferiority of combined stroke treatment.

Variation in patterns of telestroke usage during the COVID-19 pandemic

OBJECTIVES

Early in the pandemic, there was a substantial increase in telestroke uptake among hospitals. The motivations for using telestroke during the pandemic might have been different than for hospitals that adopted telestroke previously. We compared stroke care at hospitals that adopted telestroke prior to the pandemic to care at hospitals that adopted telestroke during the pandemic.

MATERIALS AND METHODS

Stroke episodes and telestroke use were identified in Medicare Fee-for-Service Data. Hospital and episode characteristics were compared between pre-pandemic (Jan. 2019-Mar. 2020) and pandemic (Apr. 2020-Dec. 2020) adopters.

RESULTS

Hospital bed counts, critical access statuses, stroke volumes, clinical operating margins, shares of stroke care via telestroke, and vascular neurology consult rates did not differ significantly between pre-pandemic and pandemic-adopting hospitals. Hospitals that never adopted telestroke during the study period were more likely to be small critical access hospitals with low clinical operating margins.

CONCLUSIONS

Compared to hospitals that adopted telestroke before the pandemic, hospitals that adopted telestroke during the pandemic were similar in characteristics and how they used telestroke.

Evolving Stroke Systems of Care: Stroke Diagnosis and Treatment in the Post-Thrombectomy Era

Thrombectomy became the gold-standard treatment of acute ischemic stroke caused by large-vessel occlusions (LVO) in 2015 after five clinical trials published that year demonstrated significantly improved patient outcomes. In subsequent years, advances in stroke systems of care have centered around improving access to and expanding patient eligibility for thrombectomy. The prehospital and acute stroke treatment settings have had the greatest emphasis. Numerous prehospital stroke scales now provide emergency medical services with focused physical exams to identify LVOs, and many devices to non-invasively detect LVO are undergoing clinical testing. Mobile stroke units deployed throughout Western Europe and the USA also show promising results by bringing elements of acute stroke care directly to the patient. Numerous clinical trials since 2015 have aimed to increase candidates for thrombectomy by expanding indications and the eligibility time window. Further optimizations of thrombectomy treatment have focused on the role of thrombolytics and other adjunctive therapies that may promote neuroprotection and neurorecovery. While many of these approaches require further clinical investigation, the next decade shows significant potential for further advances in stroke care.

Patterns of Care in Patients with Basilar Artery Occlusion (BAO): A Population-Based Study

Basilar artery occlusion (BAO) is associated with high morbidity and mortality. Endovascular therapy (EVT) has been shown to be beneficial in acute BAO patients. This retrospective observational study used the National Inpatient Sample (NIS) database to identify BAO patients using the International Classification of Diseases (ICD). Multivariable models were used to evaluate the association of risk factors, comorbidities, length of stay (LOS) in hospital, total cost, disposition, and transfer status. A total of 1120 (447 females, 39.95%) patients were identified, with a higher proportion of White individuals (66.8% vs. 57.6%), atrial fibrillation (31.5% vs. 17.2%; p < 0.0001), and peripheral vascular disease (21.2% vs. 13.7%; p = 0.009). A lower proportion of individuals with diabetes mellitus (32.1% vs. 39.5%; p = 0.05) was found in the EVT group. Majority of the patients (924/1120, 82.5%) were treated at the urban teaching facility, which also performed most of the EVT procedures (164, 89.13%), followed by non-academic urban (166, 14.8%) and rural (30, 2.7%) hospitals. Most patients (19/30, 63%) admitted to rural hospitals were transferred to other facilities. Urban academic hospitals also had the highest median LOS (8.9 days), cost of hospitalization (USD 117,261), and disposition to home (32.6%). This study observed distinct patterns and geographical disparities in the acute treatment of BAO patients. There is a need for national- and state-level strategies to improve access to stroke care.

Interactive Direct Interhospital Transfer Network System for Acute Stroke in South Korea

BACKGROUND AND PURPOSE

Interhospital transfer is an essential practical component of regional stroke care systems. To establish an effective stroke transfer network in South Korea, an interactive transfer system was constructed, and its workflow metrics were observed.

METHODS

In March 2019, a direct transfer system between primary stroke hospitals (PSHs) and comprehensive regional stroke centers (CSCs) was established to standardize the clinical pathway of imaging, recanalization therapy, transfer decisions, and exclusive transfer linkage systems in the two types of centers. In an active case, the time metrics from arrival at PSH ("door") to imaging was measured, and intravenous thrombolysis (IVT) and endovascular treatment (EVT) were used to assess the differences in clinical situations.

RESULTS

The direct transfer system was used by 27 patients. They stayed at the PSH for a median duration of 72 min (interquartile range [IQR], 38-114 min), with a median times of 15 and 58 min for imaging and subsequent processing, respectively. The door-to-needle median times of subjects treated with IVT at PSHs (n=5) and CSCs (n=2) were 21 min (IQR, 20.0-22.0 min) and 137.5 min (IQR, 125.3-149.8 min), respectively. EVT was performed on seven subjects (25.9%) at CSCs, which took a median duration of 175 min; 77 min at the PSH, 48 min for transportation, and 50 min at the CSC. Before EVT, bridging IVT at the PSH did not significantly affect the door-to-puncture time (127 min vs. 143.5 min, p=0.86).

CONCLUSIONS

The direct and interactive transfer system is feasible in real-world practice in South Korea and presents merits in reducing the treatment delay by sharing information during transfer.

Association of Time of Day With Outcomes Among Patients Triaged for a Suspected Severe Stroke in Nonurban Catalonia

BACKGROUND

We aim to assess whether time of day modified the treatment effect in the RACECAT trial (Direct Transfer to an Endovascular Center Compared to Transfer to the Closest Stroke Center in Acute Stroke Patients With Suspected Large Vessel Occlusion Trial), a cluster-randomized trial that did not demonstrate the benefit of direct transportation to a thrombectomy-capable center versus nearest local stroke center for patients with a suspected large vessel stroke triaged in nonurban Catalonia between March 2017 and June 2020.

METHODS

We performed a post hoc analysis of RACECAT to evaluate if the association between initial transport routing and functional outcome differed according to trial enrollment time: daytime (8:00 am-8:59 pm) and nighttime (9:00 pm-7:59 am). Primary outcome was disability at 90 days, as assessed by the shift analysis on the modified Rankin Scale score, in patients with ischemic stroke. Subgroup analyses according to stroke subtype were evaluated.

RESULTS

We included 949 patients with an ischemic stroke, of whom 258 patients(27%) were enrolled during nighttime. Among patients enrolled during nighttime, direct transport to a thrombectomy-capable center was associated with lower degrees of disability at 90 days (adjusted common odds ratio [acOR], 1.620 [95% CI, 1.020-2.551]); no significant difference between trial groups was present during daytime (acOR, 0.890 [95% CI, 0.680-1.163]; P _interaction=0.014). Influence of nighttime on the treatment effect was only evident in patients with large vessel occlusion(daytime, acOR 0.766 [95% CI, 0.548-1.072]; nighttime, acOR, 1.785 [95% CI, 1.024-3.112] ; P _interaction<0.01); no heterogeneity was observed for other stroke subtypes (P _interaction>0.1 for all comparisons). We observed longer delays in alteplase administration, interhospital transfers, and mechanical thrombectomy initiation during nighttime in patients allocated to local stroke centers.

CONCLUSIONS

Among patients evaluated during nighttime for a suspected acute severe stroke in non-urban areas of Catalonia, direct transport to a thrombectomy-capable center was associated with lower degrees of disability at 90 days. This association was only evident in patients with confirmed large vessel occlusion on vascular imaging. Time delays in alteplase administration and interhospital transfers might mediate the observed differences in clinical outcome.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT02795962.

Artificial Intelligence-Assisted Software Significantly Decreases All Workflow Metrics for Large Vessel Occlusion Transfer Patients, within a Large Spoke and Hub System

INTRODUCTION

Artificial intelligence (AI) software is increasingly applied in stroke diagnostics. Viz LVO (large vessel occlusion) is an AI-based software that is FDA-approved for LVO detection in CT angiography (CTA) scans. We sought to investigate differences in transfer times (from peripheral [spoke] to central [hub] hospitals) for LVO patients between spoke hospitals that utilize Viz LVO and those that do not.

METHODS

In this retrospective cohort study, we used our institutional database to identify all suspected/confirmed LVO-transferred patients from spokes (peripheral hospitals) within and outside of our healthcare system, from January 2020 to December 2021. The "Viz-transfers" group includes all LVO transfers from spokes within our system where Viz LVO is readily available, while the "Non-Viz-transfers" group (control group) is comprised of all LVO transfers from spokes outside our system, without Viz LVO. Primary outcome included all available time metrics from peripheral CTA commencement.

RESULTS

In total, 78 patients required a transfer. Despite comparable peripheral hospital door to peripheral hospital CTA times (20.5 [24.3] vs. 32 [45] min, p = 0.28) and transfer (spoke to hub) time (23 [18] vs. 26 [13.5], p = 0.763), all workflow metrics were statistically significantly shorter in the Viz-transfers group. Peripheral CTA to interventional neuroradiology team notification was 12 (16.8) versus 58 (59.5), p < 0.001, and peripheral CTA to peripheral departure was 91.5 (37) versus 122.5 (68.5), p < 0.001. Peripheral arrival to peripheral departure was 116.5 (75.5) versus 169 (126.8), p = 0.002, and peripheral arrival to central arrival was 145 (62.5) versus 207 (97.8), p < 0.001. In addition, peripheral CTA to angiosuite arrival was 121 (41) versus 207 (92.5), p < 0.001, peripheral CTA to arterial puncture was 146 (53) versus 234 (99.8), p < 0.001, and peripheral CTA to recanalization was 198 (25) versus 253.5 (86), p < 0.001.

CONCLUSION

Within our spoke and hub system, Viz LVO significantly decreased all workflow metrics for patients who were transferred from spokes with versus without Viz.