Ultraearly Intravenous Thrombolysis for Acute Ischemic Stroke in Mobile Stroke Unit and Hospital Settings

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

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

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.

Golden Hour Treatment With tPA (Tissue-Type Plasminogen Activator) in the BEST-MSU Study

BACKGROUND

Treatment of patients with acute ischemic stroke on mobile stroke units (MSUs) improves outcomes compared with management by standard emergency medical services ambulances and is associated with more patients treated with intravenous tPA (tissue-type plasminogen activator) in the first golden hour after last known normal. We explored the predictors and outcomes of first-hour treatment (FHT) compared with later treatment in an alternating-week cluster-controlled trial of MSUs.

METHODS

We analyzed all patients treated with intravenous tPA in the BEST-MSU Study (Benefits of Stroke Treatment Delivered by a Mobile Stroke Unit Compared to Standard Management by Emergency Medical Services). After stratifying by treatment timeframe, we identified factors associated with FHT. We performed adjusted analyses of the association between FHT and clinical outcome and modeled the shape of the relationship between last known normal-to-treatment time and excellent outcome.

RESULTS

Among 941 tPA-treated patients, 206 (21.8%) had lytic started within 60 minutes. Treatment on the MSU, older age, male sex, alert by 911, faster arrival on-scene and imaging, more severe stroke, atrial fibrillation, and absence of heart failure and pretreatment antihypertensive treatment were associated with FHT. Compared with later treatment, FHT was associated with higher adjusted odds ratio for 90-day modified Rankin Scale score of 0 to 1 (odds ratio, 1.87 [95% CI, 1.25-2.84]; P=0.003). Among FHT patients, 68% achieved a 90-day modified Rankin Scale of 0 or 1 or returned to their baseline status. FHT was not associated with higher risk of hemorrhage and was associated with reduced risk of treating neurovascular mimics.

CONCLUSIONS

FHT almost doubles the odds of excellent clinical outcome without increased risk compared with later treatment, which supports the use of MSUs.

Comparison of Mobile Stroke Unit With Usual Care for Acute Ischemic Stroke Management: A Systematic Review and Meta-analysis

IMPORTANCE

So far, uncertainty remains as to whether there is sufficient cumulative evidence that mobile stroke unit (MSU; specialized ambulance equipped with computed tomography scanner, point-of-care laboratory, and neurological expertise) use leads to better functional outcomes compared with usual care.

OBJECTIVE

To determine with a systematic review and meta-analysis of the literature whether MSU use is associated with better functional outcomes in patients with acute ischemic stroke (AIS).

DATA SOURCES

MEDLINE, Cochrane Library, and Embase from 1960 to 2021.

STUDY SELECTION

Studies comparing MSU deployment and usual care for patients with suspected stroke were eligible for analysis, excluding case series and case-control studies.

DATA EXTRACTION AND SYNTHESIS

Independent data extraction by 2 observers, following the PRISMA and MOOSE reporting guidelines. The risk of bias in each study was determined using the ROBINS-I and RoB2 tools. In the case of articles with partially overlapping study populations, unpublished disentangled results were obtained. Data were pooled in random-effects meta-analyses.

MAIN OUTCOMES AND MEASURES

The primary outcome was excellent outcome as measured with the modified Rankin Scale (mRS; score of 0 to 1 at 90 days).

RESULTS

Compared with usual care, MSU use was associated with excellent outcome (adjusted odds ratio [OR], 1.64; 95% CI, 1.27-2.13; P < .001; 5 studies; n = 3228), reduced disability over the full range of the mRS (adjusted common OR, 1.39; 95% CI, 1.14-1.70; P = .001; 3 studies; n = 1563), good outcome (mRS score of 0 to 2: crude OR, 1.25; 95% CI, 1.09-1.44; P = .001; 6 studies; n = 3266), shorter onset-to-intravenous thrombolysis (IVT) times (median reduction, 31 minutes [95% CI, 23-39]; P < .001; 13 studies; n = 3322), delivery of IVT (crude OR, 1.83; 95% CI, 1.58-2.12; P < .001; 7 studies; n = 4790), and IVT within 60 minutes of symptom onset (crude OR, 7.71; 95% CI, 4.17-14.25; P < .001; 8 studies; n = 3351). MSU use was not associated with an increased risk of all-cause mortality at 7 days or at 90 days or with higher proportions of symptomatic intracranial hemorrhage after IVT.

CONCLUSIONS AND RELEVANCE

Compared with usual care, MSU use was associated with an approximately 65% increase in the odds of excellent outcome and a 30-minute reduction in onset-to-IVT times, without safety concerns. These results should help guideline writing committees and policy makers.

European Stroke Organisation (ESO) guidelines on mobile stroke units for prehospital stroke management

The safety and efficacy of mobile stroke units (MSUs) in prehospital stroke management has recently been investigated in different clinical studies. MSUs are ambulances equipped with a CT scanner, point-of-care lab, telemedicine and are staffed with a stroke specialised medical team. This European Stroke Organisation (ESO) guideline provides an up-to-date evidence-based recommendation to assist decision-makers in their choice on using MSUs for prehospital management of suspected stroke, which includes patients with acute ischaemic stroke (AIS), intracranial haemorrhage (ICH) and stroke mimics. The guidelines were developed according to the ESO standard operating procedure and Grading of Recommendations, Assessment, Development and Evaluation (GRADE) methodology. The working group identified relevant clinical questions, performed systematic reviews and aggregated data meta-analyses of the literature, assessed the quality of the available evidence and made specific recommendations. Expert consensus statements are provided where sufficient evidence was not available to provide recommendations based on the GRADE approach. We found moderate evidence for suggesting MSU management for patients with suspected stroke. The patient group diagnosed with AIS shows an improvement of functional outcomes at 90 days, reduced onset to treatment times and increased proportion receiving IVT within 60 min from onset. MSU management might be beneficial for patients with ICH as MSU management was associated with a higher proportion of ICH patients being primarily transported to tertiary care stroke centres. No safety concerns (all-cause mortality, proportion of stroke mimics treated with IVT, symptomatic intracranial bleeding and major extracranial bleeding) could be identified for all patients managed with a MSU compared to conventional care. We suggest MSU management to improve prehospital management of suspected stroke patients.

Mobile Stroke Units: Current Evidence and Impact

PURPOSE OF REVIEW

Several approaches have been developed to optimize prehospital systems for acute stroke given poor access and significant delays to timely treatment. Specially equipped ambulances that directly initiate treatment, known as Mobile Stroke Units (MSUs), have rapidly proliferated across the world. This review provides a comprehensive summary on the efficacy of MSUs in acute stroke, its various applications beyond thrombolysis, as well as the establishment, optimal setting and cost-effectiveness of incorporating an MSU into healthcare systems.

RECENT FINDINGS

MSUs speed stroke treatment into the first "golden hour" when better outcomes from thrombolysis are achieved. While evidence for the positive impact of MSUs on outcomes was previously unavailable, two recent landmark controlled trials, B_PROUD and BEST-MSU, show that MSUs result in significantly lesser disability compared to conventional ambulance care. Emerging literature prove the significant impact of MSUs. Adaptability however remains limited by significant upfront financial investment, challenges with reimbursements and pending evidence on their cost-effectiveness.

Building a Mobile Stroke Unit Based on 5G Technology - A Study Protocol

Background: In-time treatment of acute stroke is critical to saving people's lives and improving the quality of post-stroke life. A mobile stroke unit (MSU) with fifth-generation (5G) mobile networks strengthens the interaction of patient information and healthcare resources, thereby reducing response times and improving thrombolysis results. However, clinical evidence of better outcomes compared to regular care is still lacking. Method and Design: In this randomized controlled trial, 484 patients with acute stroke are allocated into the MSU and regular care groups. We establish medical records for each patient and conduct a follow-up of 90 days. The primary outcomes are functional results as defined by utility-weighted modified Rankin Scale (uw-mRS) 90 days after the incidence occurred, whereas secondary outcomes include the alarm to CT scan completed time, the alarm to treatment decision time, the alarm to thrombolytic time, quality of life, and symptomatic intracranial hemorrhage combined with NIHSS score as well as cost-effectiveness. Discussion: This study establishes an innovative MSU (based on 5G) to manage acute stroke, comparing its clinical and economic outcomes to regular care and informing decision-makers of the effectiveness of the stroke emergency system. Clinical Trial Registration: [http://www.chictr.org.cn/showproj.aspx?proj=63874], identifier [ChiCTR2000039695].

Drip-and-Ship for Thrombectomy Treatment in Patients With Acute Ischemic Stroke Leads to Inferior Clinical Outcomes in a Stroke Network Covering Vast Rural Areas Compared to Direct Admission to a Comprehensive Stroke Center

Introduction: Organizing regional stroke care considering thrombolysis as well as mechanical thrombectomy (MTE) remains challenging in light of a wide range of regional population distribution. To compare outcomes of patients in a stroke network covering vast rural areas in southwestern Germany who underwent MTE via direct admission to a single comprehensive stroke center [CSC; mothership (MS)] with those of patients transferred from primary stroke centers [PSCs; drip-and-ship (DS)], we undertook this analysis of consecutive stroke patients with MTE.

Materials and Methods: Patients who underwent MTE at the CSC between January 2013 and December 2016 were included in the analysis. The primary outcome measure was 90-day functional independence [modified Rankin score (mRS) 0–2]. Secondary outcome measures included time from stroke onset to recanalization/end of MTE, angiographic outcomes, and mortality rates.

Results: Three hundred and thirty-two consecutive patients were included (MS 222 and DS 110). Median age was 74 in both arms of the study, and there was no significant difference in baseline National Institutes of Health Stroke Scale scores (median MS 15 vs. 16 DS). Intravenous (IV) thrombolysis (IVT) rates differed significantly (55% MS vs. 70% DS, p = 0.008). Time from stroke onset to recanalization/end of MTE was 112 min shorter in the MS group (median 230 vs. 342 min, p < 0.001). Successful recanalization [thrombolysis in cerebral infarction (TICI) 2b-3] was achieved in 72% of patients in the MS group and 73% in the DS group. There was a significant difference in 90-day functional independence (37% MS vs. 24% DS, p = 0.017), whereas no significant differences were observed for mortality rates at 90 days (MS 22% vs. DS 17%, p = 0.306).

Discussion: Our data suggest that patients who had an acute ischemic stroke admitted directly to a CSC may have better 90-day outcomes than those transferred secondarily for thrombectomy from a PSC.

High-resolution CT with arch/neck/head CT angiography on a mobile stroke unit

BACKGROUND

Mobile stroke units (MSUs) performance dependability and diagnostic yield of 16-slice, ultra-fast CT with auto-injection angiography (CTA) of the aortic arch/neck/circle of Willis has not been previously reported.

METHODS

We performed a prospective observational study of the first-of-its kind MSU equipped with high resolution, 16-slice CT with multiphasic CTA. Field CT/CTA was performed on all suspected stroke patients regardless of symptom severity or resolution. Performance dependability, efficiency and diagnostic yield over 365 days was quantified.

RESULTS

1031 MSU emergency activations occurred; of these, 629 (61%) were disregarded with unrelated diagnoses, and 402 patients transported: 245 (61%) ischemic or hemorrhagic stroke, 17 (4%) transient ischemic attack, 140 (35%) other neurologic emergencies. Total time from non-contrast CT/CTA start to images ready for viewing was 4.0 (IQR 3.5-4.5) min. Hemorrhagic stroke totaled 24 (10%): aneurysmal subarachnoid hemorrhage 3, hemorrhagic infarct 1, and 20 intraparenchymal hemorrhages (median intracerebral hemorrhage score was 2 (IQR 1-3), 4 (20%) spot sign positive). In 221 patients with ischemic stroke, 73 (33%) received alteplase with 31.5% treated within 60 min of onset. CTA revealed large vessel occlusion in 66 patients (30%) of which 9 (14%) were extracranial; 27 (41%) underwent thrombectomy with onset to puncture time averaging 141±90 min (median 112 (IQR 90-139) min) with full emergency department (ED) bypass. No imaging needed to be repeated for image quality; all patients were triaged correctly with no inter-hospital transfer required.

CONCLUSIONS

MSU use of advanced imaging including multiphasic head/neck CTA is feasible, offers high LVO yield and enables full ED bypass.

Digital health in stroke medicine: what are the opportunities for stroke patients?

PURPOSE OF REVIEW

The European Stroke Organisation published a European Stroke Action Plan (SAP-E) for the years 2018-2030. The SAP-E addresses the entire chain of care from primary prevention through to life after stroke. Within this document digital health tools are suggested for their potential to facilitate greater access to stroke care. In this review, we searched for digital health solutions for every domain of the SAP-E.

RECENT FINDINGS

Currently available digital health solutions for the cerebrovascular disease have been designed to support professionals and patients in healthcare settings at all stages. Telemedicine in acute settings has notably increased the access to tissue plasminogen activator and thrombectomy whereas in poststroke settings it has improved access to rehabilitation. Moreover, numerous applications aim to monitor vital signs and prescribed treatment adherence.

SUMMARY

SAP-E with its seven domains covers the whole continuum of stroke care, where digital health solutions have been considered to provide utility at a low cost. These technologies are progressively being used in all phases of stroke care, allowing them to overcome geographical and organizational barriers. The commercially available applications may also be used by patients and their careers in various context to facilitate accessibility to health improvement strategies.

Ultraearly thrombolysis by an anesthesiologist in a mobile stroke unit: A prospective, controlled intervention study

BACKGROUND

Acute stroke treatment in mobile stroke units (MSU) is feasible and reduces time-to-treatment, but the optimal staffing model is unknown. We wanted to explore if integrating thrombolysis of acute ischemic stroke (AIS) in an anesthesiologist-based emergency medical services (EMS) reduces time-to-treatment and is safe.

METHODS

A nonrandomized, prospective, controlled intervention study.

INCLUSION CRITERIA

age ≥18 years, nonpregnant, stroke symptoms with onset ≤4 h. The MSU staffing is inspired by the Norwegian Helicopter Emergency Medical Services crew with an anesthesiologist, a paramedic-nurse and a paramedic. Controls were included by conventional ambulances in the same catchment area. Primary outcome was onset-to-treatment time. Secondary outcomes were alarm-to-treatment time, thrombolytic rate and functional outcome. Safety outcomes were symptomatic intracranial hemorrhage and mortality.

RESULTS

We included 440 patients. MSU median (IQR) onset-to-treatment time was 101 (71-155) minutes versus 118 (90-176) minutes in controls, p = 0.007. MSU median (IQR) alarm-to-treatment time was 53 (44-65) minutes versus 74 (63-95) minutes in controls, p < 0.001. Golden hour treatment was achieved in 15.2% of the MSU patients versus 3.7% in the controls, p = 0.005. The thrombolytic rate was higher in the MSU (81% vs 59%, p = 0.001). MSU patients were more often discharged home (adjusted OR [95% CI]: 2.36 [1.11-5.03]). There were no other significant differences in outcomes.

CONCLUSIONS

Integrating thrombolysis of AIS in the anesthesiologist-based EMS reduces time-to-treatment without negatively affecting outcomes. An MSU based on the EMS enables prehospital assessment of acute stroke in addition to other medical and traumatic emergencies and may facilitate future implementation.

A review of mobile stroke units

PURPOSE OF REVIEW

Mobile stroke units (MSUs) for prehospital treatment and management of patients with acute stroke have been developed more than a decade ago and is currently spreading worldwide. This review discusses the history of MSU and current operations and research.

RECENT FINDINGS

Multiple studies have shown that MSU can significantly reduce treatment time with a tenfold increase of patients treated within the first 60 min of symptom onset. Recent preliminary results from the Berlin Prehospital or Usual Delivery of Acute Stroke Care trial (B-PROUD) showed a positive shift in modified Rankin Scale (mRS) scores at 3 months for patients treated in MSUs. Two German studies indicate that the MSU model is cost effective by reducing disability and improving adjusted quality-life years after stroke. The MSU model for prehospital management of acute stroke is spreading worldwide. More research is needed, however, to establish cost-effectiveness, efficacy and best setting for prehospital stroke management.

Utstein recommendation for emergency stroke care

Background

Recent advances in treatment for stroke give new possibilities for optimizing outcomes. To deliver these prehospital care needs to become more efficient.

Aim

To develop a framework to support improved delivery of prehospital care. The recommendations are aimed at clinicians involved in prehospital and emergency health systems who will often not be stroke specialists but need clear guidance as to how to develop and deliver safe and effective care for acute stroke patients.

Methods

Building on the successful implementation program from the Global Resuscitation Alliance and the Resuscitation Academy, the Utstein methodology was used to define a generic chain of survival for Emergency Stroke Care by assembling international expertise in Stroke and Emergency Medical Services (EMS). Ten programs were identified for Acute Stroke Care to improve survival and outcomes, with recommendations for implementation of best practice.

Conclusions

Efficient prehospital systems for acute stroke will be improved through public awareness, optimized prehospital triage and timely diagnostics, and quick and equitable access to acute treatments. Documentation, use of metrics and transparency will help to build a culture of excellence and accountability.

Acute telestroke in France: A systematic review

BACKGROUND

Acute telestroke is the use of telemedicine to improve acute stroke care. It has demonstrated to be a safe and effective medical practice. Since 2011, acute telestroke has been promoted by the Ministry of Health in France, and in 2018 many regions were in the process or completion of implementing telestroke. The objective of this study was to describe acute telestroke implementation in France.

METHODS

A systematic review was conducted using PubMed and ScienceDirect databases. Articles and abstracts in English and French, published between January 1st, 2000 to April 30th, 2018 were used. Studies conducted in France and that had presented an outcome evaluation of a regional acute telestroke activity were included. No meta-analysis was conducted.

RESULTS

A total of 24 studies (14 in French, 10 in English) were included, with 13 published articles (7 indexed on PubMed) and 11 abstracts. Among the 13 published articles, there were seven observational retrospective studies, one quasi-experimental before-after study, one experimental randomised controlled trial, and four medico-economic studies. All telestroke network models of care were drip-and-ship with hub and spoke organisation. The case-control studies did not show a difference with or without telemedicine. The territorial thrombolysis rate was measured in two regions, with an increase in Franche-Comté from 0.2% (2004) to 9.9% (2015), and a relative increase of 76% in Nord-Pas-de-Calais between 2009-2010 and 2012.

CONCLUSION

Implementation of acute telestroke in France had a positive clinical and public health impact but the evaluation remained limited and needs to be supported.

Cost-Consequence Analysis of Mobile Stroke Units vs. Standard Prehospital Care and Transport

Background: Mobile stroke units (MSUs) are the latest approach to improving time-sensitive stroke care delivery. Currently, there are no published studies looking at the expanded value of the MSU to diagnose and transport patients to the closest most appropriate facility. The purpose of this paper is to perform a cost consequence analysis of standard transport (ST) vs. MSU.

Methods and Results: A cost consequence analysis was undertaken within a decision framework to compare the incremental cost of care for patients with confirmed stroke that were served by the MSU vs. their simulated care had they been served by standard emergency medical services between July 2014 and October 2015. At baseline values, the incremental cost between MSU and ST was $70,613 ($856,482 vs. $785,869) for 355 patient transports. The MSU avoided 76 secondary interhospital transfers and 76 emergency department (ED) encounters. Sensitivity analysis identified six variables that had measurable impact on the model's variability and a threshold value at which MSU becomes the optimal strategy: number of stroke patients (>391), probability of requiring transfer to a comprehensive stroke center (CSC, >0.52), annual cost of MSU operations (<$696,053), cost of air transfer (>$8,841), probability initial receiving hospital is a CSC (<0.32), and probability of ischemic stroke with ST (<0.76).

Conclusions: MSUs can avert significant costs in the administration of stroke care once optimal thresholds are achieved. A comprehensive cost-effectiveness analysis is required to determine not just the operational value of an MSU but also its clinical value to patients and the society.

Mobile Stroke Units: Bringing Treatment to the Patient

PURPOSE OF REVIEW

Mobile stroke units (MSUs) have revolutionized emergency stroke care by delivering pre-hospital thrombolysis faster than conventional ambulance transport and in-hospital treatment. This review discusses the history of MSUs technological development, current operations and research, cost-effectiveness, and future directions.

RECENT FINDINGS

Multiple prospective and retrospective studies have shown that MSUs deliver acute ischemic stroke treatment with intravenous recombinant tissue plasminogen activator (IV r-tPA) approximately 30 min faster than conventional care. The 90-day modified Rankin Scores for patients who received IV r-tPA on the MSU compared to conventional care were not statistically different in the PHANTOM-S study. Two German studies suggest that the MSU model is cost-effective by reducing disability and improving adjusted quality-life years post-stroke. The ongoing BEST-MSU trial will be the first multicenter, randomized controlled study that will shed light on MSUs' impact on long-term neurologic outcomes and cost-effectiveness. MSUs are effective in reducing treatment times in acute ischemic stroke without increasing adverse events. MSUs could potentially improve treatment times in large vessel occlusion and intracranial hemorrhage. Further studies are needed to assess functional outcomes and cost-effectiveness. Clinical trials are ongoing internationally.

Timing of Recanalization and Functional Recovery in Acute Ischemic Stroke

Background and Purpose

Although onset-to-treatment time is associated with early clinical recovery in acute ischemic stroke (AIS) patients treated with intravenous tissue plasminogen activator (tPA), the effect of the timing of tPA-induced recanalization on functional outcomes remains debatable.

Methods

We conducted a multicenter, prospective observational cohort study to determine whether early (within 1-hour from tPA-bolus) complete or partial recanalization assessed during 2-hour real-time transcranial Doppler monitoring is associated with improved outcomes in patients with proximal occlusions. Outcome events included dramatic clinical recovery (DCR) within 2 and 24-hours from tPA-bolus, 3-month mortality, favorable functional outcome (FFO) and functional independence (FI) defined as modified Rankin Scale (mRS) scores of 0–1 and 0–2 respectively.

Results

We enrolled 480 AIS patients (mean age 66±15 years, 60% men, baseline National Institutes of Health Stroke Scale score 15). Patients with early recanalization (53%) had significantly (jos-2019-01648P<0.001) higher rates of DCR at 2-hour (54% vs. 10%) and 24-hour (63% vs. 22%), 3-month FFO (67% vs. 28%) and FI (81% vs. 39%). Three-month mortality rates (6% vs. 17%) and distribution of 3-month mRS scores were significantly lower in the early recanalization group. After adjusting for potential confounders, early recanalization was independently associated with higher odds of 3-month FFO (odds ratio [OR], 6.19; 95% confidence interval [CI], 3.88 to 9.88) and lower likelihood of 3-month mortality (OR, 0.34; 95% CI, 0.17 to 0.67). Onset to treatment time correlated to the elapsed time between tPA-bolus and recanalization (unstandardized linear regression coefficient, 0.13; 95% CI, 0.06 to 0.19).

Conclusions

Earlier tPA treatment after stroke onset is associated with faster tPA-induced recanalization. Earlier onset-to-recanalization time results in improved functional recovery and survival in AIS patients with proximal intracranial occlusions.

Is intravenous thrombolysis still necessary in patients who undergo mechanical thrombectomy?

PURPOSE OF REVIEW

To summarize available evidence on the potential utility of pretreatment with intravenous thrombolysis (IVT) using recombinant tissue-plasminogen activator (rt-PA) in acute ischemic stroke (AIS) patients with large vessel occlusions (LVO) who are treated with mechanical thrombectomy.

RECENT FINDINGS

Despite theoretical concerns of a higher bleeding risk with IVT pretreatment, there are no data showing increased risk of symptomatic intracerebral hemorrhage (sICH) in patients with LVO receiving bridging therapy (IVT and mechanical thrombectomy) compared with direct mechanical thrombectomy (dMT). Additionally, evidence from observational studies suggest lower rates of infarctions in previously unaffected territories and higher rates of successful reperfusion, with lower number of device passes, in patients receiving bridging therapy. There are substantial discrepancies in studies comparing clinical outcomes between dMT and bridging therapy that are directly related to the inclusion of patients with contraindications to IVT in the dMT group. Ongoing clinical trials will provide definitive answers on the potential additional benefit of IVT in LVO patients receiving mechanical thrombectomy.

SUMMARY

IVT and mechanical thrombectomy are two effective reperfusion therapies that should be used in a swift and noncompeting fashion in AIS patients. AIS patients with LVO and no contraindications for IVT should receive promptly rt-PA bolus followed by immediate initiation of mechanical thrombectomy as indicated by current international recommendations, unless future randomized controlled trials provide evidence to proceed differently.

Safety, Pharmacokinetics and Pharmacodynamics of TNHH, a Novel Targeted Neutrophil-Inhibitory Hirulog Hybrid Glycoprotein, in Healthy Volunteers

BACKGROUND

Targeted neutrophil inhibitory-hirulog (TNHH) is a novel hybrid glycoprotein that may be a potential drug candidate for acute ischaemic stroke.

OBJECTIVE

The aim of this study was to evaluate the safety, tolerability, pharmacokinetics and pharmacodynamics of TNHH in healthy volunteers and thereby determine the dose range for future clinical studies.

METHODS

This randomized, placebo-controlled study was a single ascending dose design with dose levels of 0.05-1.8 mg/kg (n = 4-6 active, 2 placebos per cohort) in 68 participants. In the TNHH 0.2-1.8 mg/kg and control cohorts, pharmacokinetic and pharmacodynamic blood samples were collected over 168 h after intravenous (IV) administration. TNHH occupancy in peripheral blood neutrophils and blood coagulation were evaluated as the markers of target engagement.

RESULTS

Two subjects withdrew from the trial before administration of the study treatment, 66 subjects are included in the data analysis. TNHH was well tolerated in all dose regimens. In total, five mild, self-limiting adverse events (AEs) were observed in 4 of the 66 study subjects. Dose-proportional increases in maximum plasma concentration (C_max) and area under the curve (AUC_0-t) of TNHH were observed. Traces of TNHH were excreted in urine. The elimination half-life (t_½) ranged from 0.6 to 1.3 h in the eight groups with ascending dose levels. TNHH combined with CD11b/CD18 quickly achieved > 90% receptor occupancy in groups with doses above 0.2 mg/kg. The C_max and AUC of binding TNHH with CD11b/CD18 increased with the dose. A significant prolongation with dose was observed on thrombin time (TT), and weak influences were observed on prothrombin time (PT) and activated partial thromboplastin time (APTT).

CONCLUSION

TNHH was well-tolerated following IV infusion. The pharmacokinetic and pharmacodynamic characteristics of TNHH indicate that it merits clinical trials. It is recommended that the single dose of TNHH should be 1.0 mg/kg in future studies, and the expected effect may be achieved after 5-7 days of continuous administration.

TRIAL REGISTRATION

The study is registered at http://www.chictr.org.cn as ChiCTR-TQR-14004752.

Improving Prehospital Stroke Services in Rural and Underserved Settings With Mobile Stroke Units

In acute stroke management, time is brain, as narrow therapeutic windows for both intravenous thrombolysis and mechanical thrombectomy depend on expedient and specialized treatment. In rural settings, patients are often far from specialized treatment centers. Concurrently, financial constraints, cutting of services and understaffing of specialists for many rural hospitals have resulted in many patients being underserved. Mobile Stroke Units (MSU) provide a valuable prehospital resource to rural and remote settings where patients may not have easy access to in-hospital stroke care. In addition to standard ambulance equipment, the MSU is equipped with the necessary tools for diagnosis and treatment of acute stroke or similar emergencies at the emergency site. The MSU strategy has proven to be effective at facilitating time-saving stroke triage decisions. The additional on-board imaging helps to determine whether a patient should be taken to a primary stroke center (PSC) for standard treatment or to a comprehensive stroke center (CSC) for advanced stroke treatment (such as intra-arterial therapy) instead. Diagnosis at the emergency site may prevent additional in-hospital delays in workup, handover and secondary (inter-hospital) transport. MSUs may be adapted to local needs-especially in rural and remote settings-with adjustments in staffing, ambulance configuration, and transport models. Further, with advanced imaging and further diagnostic capabilities, MSUs provide a valuable platform for telemedicine (teleradiology and telestroke) in these underserved areas. As MSU programmes continue to be implemented across the world, optimal and adaptable configurations could be explored.

Effects of time delays on the therapeutic outcomes of intravenous thrombolysis for acute ischemic stroke in the posterior circulation: An observational study

OBJECTIVES

We aim to demonstrate the effects of time delays on the therapeutic outcomes of intravenous thrombolysis (IVT) in acute posterior circulation stroke (PCS) patients.

METHODS

Consecutive PCS cases treated with IVT alone were retrospectively examined. The primary end point was set to be a favorable outcome (modified Rankin Scale [mRS] ≤2) at 3 months, and angiographic recanalization was set to be the secondary outcome.

RESULTS

A total of 95 PCS cases with IVT were recruited. The patients with favorable outcomes and those without favorable outcomes had similar baseline characteristics, except for significantly lower National Institute of Health Stroke Scale (NIHSS) scores (5 vs. 12, respectively; p < 0.001) and less hyperdense basilar artery signs in head CTs (26.5% vs. 70.4%, respectively; p < 0.001) for those with favorable outcomes. For patients with an onset-to-treatment time (OTT) of 0-90 min (n = 5), 91-180 min (n = 38), 181-270 min (n = 37), or ≧271 min (n = 15), the rate of favorable outcome was 100.0%, 71.1%, 67.6%, or 73.3%, respectively, and the Cochran-Armitage trend test showed no linear trend between the OTT and the clinical prognosis of IVT in PCS (p = 0.501) patients. In addition, the rates of recanalization were 100.0%, 68.4%, 64.9%, and 46.7%, and the Cochran-Armitage trend test suggested a linear trend between the OTT and recanalization (p = 0.046); that is, the proportion of PCS patients who underwent recanalization decreased with increasing OTTs. In the multivariate logistic regression analysis, after adjusting for confounding factors with p ≦ 0.20 in the univariate analysis, baseline NIHSS scores and hyperdense basilar artery signs were negatively associated with favorable outcomes, with odds ratios (OR) of 0.884 (95% confidence interval [CI], 0.804-0.971; p = 0.010) and 0.208 (95% CI, 0.062-0.693; p = 0.011), respectively. In addition, there was a negative association between recanalization, OTTs (OR, 0.993, 95% CI, 0.987-0.999; p = 0.029), and baseline NIHSS scores (OR, 0.881, 95% CI, 0.802-0.967; p = 0.008).

CONCLUSION

Irrespective of stroke severity, the therapeutic effects of recanalization after IVT decreased significantly with longer time delays in PCS patients.