Intra-arterial prourokinase for acute ischemic stroke. The PROACT II study: a randomized controlled trial. Prolyse in Acute Cerebral Thromboembolism

JR14a: A novel antagonist of C3aR attenuates neuroinflammation in cerebral ischemia-reperfusion injury

Cerebral ischemia-reperfusion injury (CIRI), a prevalent stroke-related complication, can lead to severe brain damage. Inflammation is a crucial factor in CIRI pathogenesis, and the complement component 3a receptor (C3aR) could be a key mediator in the post-CIRI inflammatory cascade. In this study, the role of C3aR in CIRI was investigated utilizing a middle cerebral artery occlusion (MCAO) model in C3aR knockout (KO) mice. Magnetic resonance imaging (MRI) and neurofunctional assessments revealed that C3aR KO mice exhibited significantly diminished cerebral infarction and improved neurological impairments. Consequently, the focus shifted to searching for a small molecule antagonist of C3aR. JR14a, a new potent thiophene antagonist of C3aR, was injected intraperitoneally into mice 1-h post-MCAO model implementation. The mass spectrometry (MS) results indicated the ability of JR14a to penetrate the blood-brain barrier. Subsequent TTC staining and neurofunctional assessments revealed the efficacy of JR14a in reducing cerebral infarct volume and neurological impairment following MCAO. In addition, immunofluorescence (IF) and immunohistochemistry (IHC) demonstrated attenuated microglial activation, neutrophil infiltration, and blood-brain barrier disruption by JR14a in the MCAO model. Furthermore, enzyme-linked immunosorbent assay (ELISA) and Western blotting supported the role of JR14a in downregulating the expression levels of C3aR, tumor necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6), as well as the phosphorylation of p65. In conclusion, the findings suggested that C3aR could be a potential therapeutic target for CIRI, and JR14a emerged as a promising treatment candidate.

Updates in Management of Large Hemispheric Infarct

This review delves into updates in management of large hemispheric infarction (LHI), a condition affecting up to 10% of patients with supratentorial strokes. While traditional management paradigms have endured, recent strides in research have revolutionized the approach to acute therapies, monitoring, and treatment. Notably, advancements in triage methodologies and the application of both pharmacological and mechanical abortive procedures have reshaped the acute care trajectory for patients with LHI. Moreover, ongoing endeavors have sought to refine strategies for the optimal surveillance and mitigation of complications, notably space-occupying mass effect, which can ensue in the aftermath of LHI. By amalgamating contemporary guidelines with cutting-edge clinical trial findings, this review offers a comprehensive exploration of the current landscape of acute and ongoing patient care for LHI, illuminating the evolving strategies that underpin effective management in this critical clinical domain.

Focused update to guidelines for endovascular therapy for emergent large vessel occlusion: basilar artery occlusion patients

BACKGROUND

Endovascular therapy (EVT) dramatically improves clinical outcomes for patients with anterior circulation emergent large vessel occlusion (ELVO) strokes. With recent publication of two randomized controlled trials in favor of EVT for basilar artery occlusions, the Society of NeuroInterventional Surgery (SNIS) Standards and Guidelines Committee provides this focused update for the existing SNIS guideline, 'Current endovascular strategies for posterior circulation large vessel occlusion stroke.'

METHODS

A structured literature review and analysis of studies related to posterior circulation large vessel occlusion (basilar or vertebral artery) strokes treated by EVT was performed. Based on the strength and quality of the evidence, recommendations were made by consensus of the writing committee, with additional input from the full SNIS Standards and Guidelines Committee and the SNIS Board of Directors.

RESULTS

Based on the results of the most recent randomized, controlled trials on EVT for basilar or vertebral artery occlusion, the expert panel agreed on the following recommendations. For patients presenting with an acute ischemic stroke due to an acute basilar or vertebral artery occlusion confirmed on CT angiography, National Institutes of Health Stroke Scale (NIHSS) score of ≥6, posterior circulation Alberta Stroke Program Early CT Score (PC-ASPECTS) ≥6, and age 18-89 years: (1) thrombectomy is indicated within 12 hours since last known well (class I, level B-R); (2) thrombectomy is reasonable within 12-24 hours from the last known well (class IIa, level B-R); (3) thrombectomy may be considered on a case by case basis for patients presenting beyond 24 hours since last known well (class IIb, level C-EO). In addition, thrombectomy may be considered on a case by case basis for patients aged <18 years or >89 years on a case by case basis (class IIb, level C-EO).

CONCLUSIONS

The indications for EVT of ELVO strokes continue to expand and now include patients with basilar artery occlusion. Further prospective, randomized controlled trials are warranted to elucidate the efficacy and safety of EVT in populations not included in this set of recommendations, and to confirm long term outcomes.

Ischemic stroke pathophysiology: A bibliometric and visualization analysis from 1990 to 2022

Background

Pathophysiology plays a significant role in the scientific study of ischemic stroke, and has attracted increasing interest from researchers in the field. However, a comprehensive bibliometric analysis is lacking in this field. The purpose of this study is to identify the current research status and hotspots of ischemic stroke pathophysiology from a bibliometric perspective.

Methods

The Web of Science Core Collection database was searched for articles published from 1990 to 2022. CiteSpace, VOSviewer, and R package "bibliometrix" software were used to analyze countries/regions, institutions, journals, authors, papers, and keywords to predict the latest trends in ischemic stroke pathophysiology research.

Results

This analysis collected 7578 records of ischemic stroke pathophysiology. China and America emerged as the leading countries in this field, with Harvard University being the most active institution. Among journals and authors in this field, journal Stroke and author Gregory YH Lip published the most papers, while Nature Medicine was the journal with the highest citation per article. Keywords and co-citation clusters were closely related to "central nervous system", "mechanisms", "biochemistry & molecular biology" and "radiology, nuclear medicine & medical imaging", while other related fields, such as peripheral organs damage induced by the central nervous system and rehabilitation after ischemic stroke, require further research efforts.

Conclusion

This is the first bibliometric study that comprehensively mapped out the knowledge structure and development trends of ischemic stroke pathophysiology in recent 32 years, which may provide a reference for scholars to explore ischemic stroke pathophysiology.

Diverse origins of fibrinolytic enzymes: A comprehensive review

Fibrinolytic enzymes cleave fibrin which plays a crucial role in thrombus formation which otherwise leads to cardiovascular diseases. While different fibrinolytic enzymes have been purified, only a few have been utilized as clinical and therapeutic agents; hence, the search continues for a fibrinolytic enzyme with high specificity, fewer side effects, and one that can be mass-produced at a lower cost with a higher yield. In this context, this review discusses the physiological mechanism of thrombus formation and fibrinolysis, and current thrombolytic drugs in use. Additionally, an overview of the optimization, production, and purification of fibrinolytic enzymes and the role of Artificial Intelligence (AI) in optimization and the patents granted is provided. This review classifies microbial as well as non-microbial fibrinolytic enzymes isolated from food sources, including fermented foods and non-food sources, highlighting their advantages and disadvantages. Despite holding immense potential for the discovery of novel fibrinolytic enzymes, only a few fermented food sources limited to Asian countries have been studied, necessitating the research on fibrinolytic enzymes from fermented foods of other regions. This review will aid researchers in selecting optimal sources for screening fibrinolytic enzymes and is the first one to provide insights and draw a link between the implication of source selection and in vivo application.

Proper Indication of Decompressive Craniectomy for the Patients with Massive Brain Edema after Intra-arterial Thrombectomy

OBJECTIVE

Numerous studies have indicated that early decompressive craniectomy (DC) for patients with major infarction can be life-saving and enhance neurological outcomes. However, most of these studies were conducted by neurologists before the advent of intra-arterial thrombectomy (IA-Tx). This study aims to determine whether neurological status significantly impacts the final clinical outcome of patients who underwent DC following IA-Tx in major infarction.

METHODS

This analysis included 67 patients with major anterior circulation major infarction who underwent DC after IA-Tx, with or without intravenous tissue plasminogen activator. We retrospectively reviewed the medical records, radiological findings, and compared the neurological outcomes based on the "surgical time window" and neurological status at the time of surgery.

RESULTS

For patients treated with DC following IA-Tx, a Glasgow coma scale (GCS) score of 7 was the lowest score correlated with a favorable outcome (p=0.013). Favorable outcomes were significantly associated with successful recanalization after IA-Tx (p=0.001) and perfusion/diffusion (P/D)-mismatch evident on magnetic resonance imaging performed immediately prior to IA-Tx (p=0.007). However, the surgical time window (within 36 hours, p=0.389; within 48 hours, p=0.283) did not correlate with neurological outcomes.

CONCLUSION

To date, early DC surgery after major infarction is crucial for patient outcomes. However, this study suggests that the indication for DC following IA-Tx should include neurological status (GCS ≤7), as some patients treated with early DC without considering the neurological status may undergo unnecessary surgery. Recanalization of the occluded vessel and P/D-mismatch are important for long-term neurological outcomes.

Intra-arterial tenecteplase during thrombectomy for acute stroke (BRETIS-TNK II): rationale and design

BACKGROUND

Our recent pilot study suggests intra-arterial tenecteplase (TNK) during the first pass of endovascular treatment (EVT) seems safe, may increase first-pass reperfusion and good outcome in acute ischaemic stroke (AIS) patients with large-vessel occlusion (LVO).

AIMS

To determine the efficacy and safety of intra-arterial TNK administration during EVT in AIS-LVO patients presenting up to 24 hours from symptom onset.

SAMPLE SIZE ESTIMATES

A maximum of 380 patients are required to test the superiority hypothesis with 80% power according to a two-side 0.05 level of significance, stratified by age, gender, baseline systolic blood pressure, prestroke modified Rankin Scale (mRS), baseline National Institute of Health stroke scale, baseline ASPECTS, time from onset to groin puncture, intravenous thrombolysis before EVT, stroke territory and stroke aetiology.

DESIGN

Intra-arterial TNK during thrombectomy for acute stroke (BRETIS-TNK II) study is a prospective, randomised, adaptive enrichment, open-label, blinded end point, multicentre study. Eligible AIS-LVO patients are randomly assigned into the experimental group and control group with a ratio of 1:1. The experimental group will be treated with intra-arterial infusion of TNK during EVT. The control group will be treated with standard EVT.

OUTCOME

The primary end point is a favourable outcome, defined as an mRS score of 0-2 at 90 days. The primary safety end point is symptomatic intracranial haemorrhage within 48 hours, which is defined as an increase in the National Institutes of Health Stroke Scale score of ≥4 points as a result of the intracranial haemorrhage.

CONCLUSIONS

The results of BRETIS-TNK II will provide evidence for the efficacy and safety of intra-arterial TNK administration during EVT in AIS patients with LVO.

Safety and efficacy of adjunctive intra-arterial antithrombotic therapy during endovascular thrombectomy for acute ischemic stroke: a systematic review and meta-analysis

BACKGROUND

Half of patients who achieve successful recanalization following endovascular thrombectomy (EVT) for acute ischemic stroke experience poor functional outcome. We aim to investigate whether the use of adjunctive intra-arterial antithrombotic therapy (AAT) during EVT is safe and efficacious compared with standard therapy (ST) of EVT with or without prior intravenous thrombolysis.

METHODS

Electronic databases were searched (PubMed/MEDLINE, Embase, Cochrane Library) from 2010 until October 2023. Data were pooled using a random-effects model and reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Risk of bias was assessed using ROBINS-I and ROB-2. The primary outcome was functional independence (modified Rankin Scale (mRS) 0-2) at 3 months. Secondary outcomes were successful recanalization (modified Thrombolysis In Cerebral Infarction (TICI) 2b-3), symptomatic intracranial hemorrhage (sICH), and 90-day mortality.

RESULTS

41 randomized and non-randomized studies met the eligibility criteria. Overall, 15 316 patients were included; 3296 patients were treated with AAT during EVT and 12 020 were treated with ST alone. Compared with ST, patients treated with AAT demonstrated higher odds of functional independence (46.5% AAT vs 42.6% ST; OR 1.22, 95% CI 1.07 to 1.40, P=0.004, I2=48%) and a lower likelihood of 90-day mortality (OR 0.71, 95% CI 0.61 to 0.83, P<0.0001, I2=20%). The rates of sICH (OR 1.00, 95% CI 0.82 to 1.22,P=0.97, I2=13%) and successful recanalization (OR 1.09, 95% CI 0.84 to 1.42, P=0.52, I2=76%) were not significantly different.

CONCLUSION

The use of AAT during EVT may improve functional outcomes and reduce mortality rates compared with ST alone, without an increased risk of sICH. These findings should be interpreted with caution pending the results from ongoing phase III trials to establish the efficacy and safety of AAT during EVT.

Thrombolysis with Recombinant Human Prourokinase 4.5-6 h After Acute Ischemic Stroke: A Phase IIa, Randomized, and Open-Label Multicenter Clinical Trial

BACKGROUND

Ischemic stroke is a major cause of disability and death worldwide. A narrow therapeutic window profoundly constrained the utilization of alteplase.

OBJECTIVES

To investigate therapeutic effects and safety of intravenous recombinant human prourokinase (rhPro-UK) in patients with acute ischemic stroke (AIS) in the 4.5-6 h therapeutic time windows.

METHODS

We conducted a phase IIa, randomized, and open-label multicenter clinical trial. Between 4.5 and 6 h after the onset of AIS, patients were randomly administrated to receive intravenous rhPro-UK at a 50 mg or 35 mg dose. The primary endpoint was excellent functional outcome defined as modified Rankin scale (mRS) score of 1 or less at 90 days. The secondary outcome was the treatment response, which was based on an at least 4-point improvement from baseline National Institutes of Health stroke scale (NIHSS) score at 24 h after drug administration. Safety endpoints included death, symptomatic intracerebral hemorrhage (sICH), and other serious adverse events.

RESULTS

We enrolled 80 patients in the 4.5-6 h therapeutic time windows at 17 medical centers in China from December 2016 to November 2017. A total of 39 patients were treated with 50 mg rhPro-UK, and 39 were treated with 35 mg rhPro-UK. Compared with the baseline, the NIHSS score at 24 h and days 7, 14, 30, and 90 was decreased significantly among patients treated with either rhPro-UK 50 mg or 35 mg. The mean reduction in the NIHSS from baseline to 90 days after the onset was 3.56 and 5.79 in the rhPro-UK 50 mg group and the rhPro-UK 35 mg group, respectively. The rates of functional independence at 90 days of rhPro-UK 50 mg and 35 mg were 61.54% and 69.23%, respectively (P = 0.475), and the proportion of patients with functional response to treatment at 24 h were 28.21% and 33.33% (P = 0.624). No sICH occurred in the two groups, and death occurred in only one patient in the rhPro-UK 50 mg group. There was no significant difference in mortality at 90 days and the rate of other serious adverse events between two groups.

CONCLUSION

In the 4.5-6 h time window, more than 60% of patients at either dose of rhPro-UK (50 mg or 35 mg) achieved functional independence at 90 days without increased mortality and sICH risk. Thus, intravenous rhPro-UK was effective and safe for patients with AIS within 4.5-6 h after stroke onset. While no significant differences were identified between different dosages of rhPro-UK regarding clinical outcomes, it is a logical step to further test the safety and efficacy of the low dose of rhPro-UK in a well-powered phase III study.

TRIAL REGISTRATION

http://www.chictr.org.cn . Identifier: ChiCTR1800016519. Date of registration: 6 June 2018.

Meta-analysis of direct endovascular thrombectomy vs bridging therapy in the management of acute ischemic stroke with large vessel occlusion

BACKGROUND

Debates persist when using intravenous thrombolysis (IVT) before mechanical thrombectomy (MT) for acute ischemic stroke (AIS) due to large-vessel occlusion (LVO). This systematic review and meta-analysis synthesized evidence on outcomes in patients with acute ischemic stroke due to large vessel occlusion (AIS-LVO), comparing bridging therapy (BT) with MT alone.

METHOD

We conducted searches of PubMed, Scopus, Web of Science, and the Cochrane Central Register of Controlled Trials from inception to July 2023 to identify pertinent clinical trials and observational studies.

RESULT

76 studies, involving 37,658 patients, revealed no significant difference in 90-day functional independence between DEVT and BT. However, a trend favoring BT for achieving functional independence with a modified Rankin Scale (mRS) of 0-1 was observed, having Odds ratio (OR) of 0.75 (95% CI 0.66-0.86; p < 0.001). DEVT was associated with higher postprocedural mortality (OR 1.44;95% CI 1.25-1.65; p < 0.001), but a lower risk of symptomatic intracranial hemorrhage compared to BT (OR 0.855; 95% CI 0.621-1.177; p = 0.327). Successful recanalization rates favored BT, emphasizing the importance of individualized treatment decisions (OR 0.759; 95% CI 0.594-0.969; p = 0.027). Sensitivity analyses were conducted to identify key contributors to heterogeneity.

CONCLUSION

Our meta-analysis underscores the intricate equilibrium between functional efficacy and safety in the evaluation of DEVT and BT for ACS-LVO. Fundamentally, while BT appears more efficacious, concerns about safety arise due to the superior safety profile demonstrated by DEVT. Individualized treatment decisions are imperative, and further trials are warranted to enhance precision in clinical guidance.

Contemporary Methods for Detection and Intervention of Distal Medium and Small Vessel Occlusions

The efficacy of using mechanical thrombectomy for proximal large vessel occlusions has been demonstrated in multiple large-scale trials and has further raised the question of its potential utility for distal medium and small vessel occlusions (DMSVOs). Their longer, more tortuous course and smaller corresponding vascular territories render a significant challenge for detection and intervention. The aim of this study is to provide a comprehensive overview of the current imaging and endovascular intervention options for DMSVOs and review the current works in the literature. Compared with traditional computed tomography angiography (CTA) and CT perfusion, recent advances such as multiphase CTA and maps derived from the time-to-maximum parameter coupled with artificial intelligence have demonstrated increased sensitivity for the detection of DMSVOs. Furthermore, newer generations of mini stent retrievers and thromboaspiration devices have allowed for the access and navigation of smaller and more fragile distal arteries. Preliminary studies have suggested that mechanical thrombectomy using this newer generation of devices is both safe and feasible in distal medium-sized vessels, such as M2. However, endovascular intervention utilizing such contemporary methods and devices must be balanced at the discretion of operator experience and favorable vascular anatomy. Further large-scale multicenter clinical trials are warranted to elucidate the indications for as well as to strengthen the safety and efficacy of this approach.

Adjuvant intra-arterial thrombolysis during mechanical thrombectomy is an effective means of improving outcomes for patients with large vessel occlusion stroke: A systematic review and meta-analysis

OBJECTIVE

It is unknown whether adjunctive intra-arterial thrombolysis (IAT) during mechanical thrombectomy (MT) improves outcomes in patients with large vessel occlusion (LVO) stroke. This systematic review and meta-analysis aimed to compare the safety and efficacy of MT with and without IAT for the treatment of LVO stroke.

METHODS

A systematic literature search of PubMed, Embase, and the Cochrane Library was conducted to identify studies that compared rates of 3-month functional independence (modified Rankin Scale score 0-2), successful revascularization, symptomatic intracranial hemorrhage, and 3-month mortality for MT+IAT and MT alone. Meta-analyses were performed using random effects models, and effect sizes were expressed as odds ratios (ORs) and 95% confidence intervals (CIs). Heterogeneity was assessed with Cochran's Q test and I2 statistic.

RESULTS

Twelve studies met eligibility criteria, comprising one randomized controlled trial and 11 observational cohort studies involving 2584 patients. Compared to MT alone, MT+IAT had a 43% higher odds of 3-month functional independence (OR 1.43, 95% CI 1.11-1.83; I2 =21%) and a 23% decrease in odds for 3-month mortality (OR 0.77, 95% CI 0.60-0.99; I2 =0%). There were no differences in successful revascularization (OR 1.39, 95% CI 0.89-2.17; I2 =57%) or symptomatic intracranial hemorrhage (OR 0.87, 95% CI 0.56-1.35; I2 =6%) between the two groups.

CONCLUSIONS

The present study has demonstrated that, compared with MT alone, the use of adjunct IAT during MT in patients with LVO stroke resulted in better functional outcomes and lower mortality.

Milestones in the history of neurocritical care

Over the last century, significant milestones have been achieved in managing critical illness and diagnosing and treating neurological diseases. Building upon these milestones, the field of neurocritical care emerged in the 1980 and 1990 s at the convergence of critical care medicine and acute neurological treatment. This comprehensive review presents a historical account of key developments in neurocritical care in both the United States and Europe, with a special emphasis on German contributions. The scope of the review encompasses: the foundations of neurocritical care, including post-operative units in the 1920s and 30s, respiratory support during the poliomyelitis epidemics in the 40 and 50 s, cardiac and hemodynamic care in the 60 and 70 s, and stroke units in the 80 and 90 s; key innovations including cerebral angiography, computed tomography, and intracranial pressure and multi-modal monitoring; and advances in stroke, traumatic brain injury, cardiac arrest, neuromuscular disorders, meningitis and encephalitis. These advances have revolutionized the management of neurological emergencies, emphasizing interdisciplinary teamwork, evidence-based protocols, and personalized approaches to care.

Effect of intra-arterial thrombolysis following successful endovascular thrombectomy on functional outcomes in patients with large vessel occlusion acute ischemic stroke: A post-CHOICE meta-analysis

INTRODUCTION

Endovascular thrombectomy (EVT) is the standard treatment of acute ischemic stroke (AIS) due to large vessel occlusion (LVO). Although > 70% of patients in the trials assessing EVT for AIS-LVO had successful recanalization, only a third ultimately achieved favorable outcomes. A "no-reflow" phenomenon due to distal microcirculation disruption might contribute to such suboptimal outcomes. Combining intra-arterial (IA) tissue plasminogen activator (tPA) and EVT to reduce the distal microthrombi burden was investigated in a few studies. We present a pooled-data meta-analysis of the existing evidence of this combinatorial treatment.

METHODS

We followed the Preferred Reporting Items for Systematic Review and Meta-analyses (PRISMA) recommendations. We aimed to include all original studies investigating EVT plus IA tPA in AIS-LVO patients. Using R software, we calculated pooled odds ratios (ORs) with corresponding 95% confidence intervals (CI). A fixed-effects model was adopted to evaluate pooled data.

RESULTS

Five studies satisfied the inclusion criteria. Successful recanalization was comparable between the IA tPA and control groups at 82.9% and 82.32% respectively. The 90-day functional independence was similar between both groups (OR= 1.25; 95% CI= 0.92-1.70; P= 0.154). Symptomatic intracranial hemorrhage (sICH) was also comparable between both groups (OR= 0.66; 95% CI= 0.34-1.26; P= 0.304).

CONCLUSION

Our current meta-analysis does not show significant differences between EVT alone and EVT plus IA tPA in terms of functional independence or sICH. However, with the limited number of studies and included patients, more randomized controlled trials (RCTs) are needed to further investigate the benefits and safety of combined EVT and IA tPA.

Safety and Efficacy of Dual Thrombolytic Therapy With Mutant Prourokinase and Small Bolus Alteplase for Ischemic Stroke: A Randomized Clinical Trial

Importance

Dual thrombolytic treatment with small bolus alteplase and mutant prourokinase has the potential to be a safer and more efficacious treatment for ischemic stroke than alteplase alone because mutant prourokinase is designed to act only on degraded fibrin without affecting circulating fibrinogen.

Objective

To assess the safety and efficacy of this dual thrombolytic treatment compared with alteplase.

Design, Setting, and Participants

This controlled, open-label randomized clinical trial with a blinded end point was conducted from August 10, 2019, to March 26, 2022, with a total follow-up of 30 days. Adult patients with ischemic stroke from 4 stroke centers in the Netherlands were enrolled.

Interventions

Patients were randomized (1:1) to receive a bolus of 5 mg of intravenous alteplase and 40 mg of an intravenous infusion of mutant prourokinase (intervention) or usual care with 0.9 mg/kg of intravenous alteplase (control).

Main Outcomes and Measures

The primary outcome was any intracranial hemorrhage (ICH) on neuroimaging at 24 hours. Secondary outcomes included functional outcome at 30 days, symptomatic ICH, and fibrinogen levels within 24 hours. Analyses were by intention to treat. Treatment effects were adjusted for baseline prognostic factors.

Results

A total of 268 patients were randomized, and 238 (median [IQR] age, 69 [59-77] years; 147 [61.8%] male) provided deferred consent and were included in the intention-to-treat population (121 in the intervention group and 117 in the control group). The median baseline score on the National Institutes of Health Stroke Scale was 3 (IQR, 2-5). Any ICH occurred in 16 of 121 patients (13.2%) in the intervention group and 16 of 117 patients (13.7%) in the control group (adjusted odds ratio, 0.98; 95% CI, 0.46-2.12). Mutant prourokinase led to a nonsignificant shift toward better modified Rankin Scale scores (adjusted common odds ratio, 1.16; 95% CI, 0.74-1.84). Symptomatic ICH occurred in none of the patients in the intervention group and 3 of 117 patients (2.6%) in the control group. Plasma fibrinogen levels at 1 hour remained constant in the intervention group but decreased in the control group (β = 65 mg/dL; 95% CI, 26-105 mg/dL).

Conclusions and Relevance

In this trial, dual thrombolytic treatment with small bolus alteplase and mutant prourokinase was found to be safe and did not result in fibrinogen depletion. Further evaluation of thrombolytic treatment with mutant prourokinase in larger trials to improve outcomes in patients with larger ischemic strokes is needed. Overall, in patients with minor ischemic stroke who met indications for treatment with intravenous thrombolytics but were not eligible for treatment with endovascular therapy, dual thrombolytic therapy with intravenous mutant prourokinase was not superior to treatment with intravenous alteplase alone.

Trial Registration

ClinicalTrials.gov Identifier: NCT04256473.

Neurointerventional Radiology: History, Present and Future

Neurointerventional Radiology (NIR), encompassing neuroendovascular surgery, endovascular neurosurgery, and interventional neurology, is an innovative and rapidly evolving multidisciplinary specialty focused on minimally invasive therapies for a wide range of neurological disorders. This review provides a comprehensive overview of NIR, discussing the three routes into the field, highlighting their distinct training paradigms, and emphasizing the importance of unified approaches through organizations like the Society of Neurointerventional Surgery (SNIS). The paper explores the benefits of co-managed care and its potential to improve patient outcomes, as well as the role of interdisciplinary collaboration and cross-disciplinary integration in advancing the field. We discuss the various contributions of neurosurgery, radiology, and neurology to cerebrovascular surgery, aiming to inform and educate those interested in pursuing a career in neurointervention. Additionally, the review examines the adoption of innovative technologies such as robotic-assisted techniques and artificial intelligence in NIR, and their implications for patient care and the future of the specialty. By presenting a comprehensive analysis of the field of neurointervention, we hope to inspire those considering a career in this exciting and rapidly advancing specialty, and underscore the importance of interdisciplinary collaboration in shaping its future.

A comprehensive review of stroke-related signaling pathways and treatment in western medicine and traditional Chinese medicine

This review provides insight into the complex network of signaling pathways and mechanisms involved in stroke pathophysiology. It summarizes the historical progress of stroke-related signaling pathways, identifying potential interactions between them and emphasizing that stroke is a complex network disease. Of particular interest are the Hippo signaling pathway and ferroptosis signaling pathway, which remain understudied areas of research, and are therefore a focus of the review. The involvement of multiple signaling pathways, including Sonic Hedgehog (SHH), nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response element (ARE), hypoxia-inducible factor-1α (HIF-1α), PI3K/AKT, JAK/STAT, and AMPK in pathophysiological mechanisms such as oxidative stress and apoptosis, highlights the complexity of stroke. The review also delves into the details of traditional Chinese medicine (TCM) therapies such as Rehmanniae and Astragalus, providing an analysis of the recent status of western medicine in the treatment of stroke and the advantages and disadvantages of TCM and western medicine in stroke treatment. The review proposes that since stroke is a network disease, TCM has the potential and advantages of a multi-target and multi-pathway mechanism of action in the treatment of stroke. Therefore, it is suggested that future research should explore more treasures of TCM and develop new therapies from the perspective of stroke as a network disease.

Stability of navigation in catheter-based endovascular procedures

Endovascular procedures provide surgeons and other interventionalists with minimally invasive methods to treat vascular diseases by passing guidewires, catheters, sheaths and treatment devices into the vasculature to and navigate toward a treatment site. The efficiency of this navigation affects patient outcomes, but is frequently compromised by catheter "herniation", in which the catheter-guidewire system bulges out from the intended endovascular pathway so that the interventionalist can no longer advance it. Here, we showed herniation to be a bifurcation phenomenon that can be predicted and controlled using mechanical characterizations of catheter-guidewire systems and patientspecific clinical imaging. We demonstrated our approach in laboratory models and, retrospectively, in patients who underwent procedures involving transradial neurovascular procedures with an endovascular pathway from the wrist, up in the arm, around the aortic arch, and into the neurovasculature. Our analyses identified a mathematical navigation stability criterion that predicted herniation in all of these settings. Results show that herniation can be predicted through bifurcation analysis, and provide a framework for selecting catheter-guidewire systems to avoid herniation in specific patient anatomy.

Understanding ASPECTS of stroke: Inter-rater reliability between emergency medicine physician and radiologist in a rural setup

PURPOSE

The purpose is to determine the inter-rater reliability in grading ASPECTS score, between emergency medicine physician at first contact and radiologist among patients with acute ischemic stroke.

MATERIALS AND METHODS

We conducted a prospective analysis of 765 acute ischemic stroke cases referred to the Department of Radiodiagnosis in a rural-based hospital in South India, during January 2017 to October 2021. Non-contrast computed tomography (NCCT) scans of the brain were performed using GE Bright Speed Elite 128 Slice CT Scanner. ASPECTS score was calculated separately by an emergency medicine physician and radiologist. Inter-rater reliability for total and dichotomized ASPECTS (≥6 and <6) scores were assessed using statistical analysis (ICC and Cohen ĸ coefficients) on SPSS software (v17.0).

RESULTS

Inter-rater agreement for total and dichotomized ASPECTS was substantial (ICC 0.79 and Cohen ĸ 0.68) between the emergency physician and the radiologist. Mean difference in ASPECTS between the two readers was only 0.15 with standard deviation of 1.58. No proportionality bias was detected. The Bland-Altman plot was constructed to demonstrate the distribution of ASPECTS differences between the two readers.

CONCLUSION

Substantial inter-rater agreement was noted in grading ASPECTS between emergency medicine physician at first contact and radiologist, thereby confirming its robustness even in a rural setting.

History of Neurointervention

In this review article, we aim to provide a summary of the discoveries and developments that were instrumental in the evolution of the Neurointerventional field. We begin with developments in the advent of Diagnostic Cerebral Angiography and progress to cerebral aneurysm treatment, embolization in AVMs and ischemic stroke treatment. In the process we discuss many persons who were key in the development and maturation of the field. A pivotal aspect to rapid growth in the field has been the multidisciplinary involvement of the different neuroscience specialties and therefore we close out our discussion with excitement about ongoing and future developments in the field with a focus on treatments in the non-cerebrovascular disease realm.

Posterior circulation ischaemic stroke diagnosis and management

This narrative review provides an overview of the posterior circulation and the clinical features of common posterior circulation stroke (PCS) syndromes in the posterior arterial territories and how to distinguish them from mimics. We outline the hyperacute management of patients with suspected PCS with emphasis on how to identify those who are likely to benefit from intervention based on imaging findings. Finally, we review advances in treatment options, including developments in endovascular thrombectomy (EVT) and intravenous thrombolysis (IVT), and the principles of medical management and indications for neurosurgery. Observational and randomised clinical trial data have been equivocal regarding EVT in PCS, but more recent studies strongly support its efficacy. There have been concomitant advances in imaging of posterior stroke to guide optimal patient selection for thrombectomy. Recent evidence suggests that clinicians should have a heightened suspicion of posterior circulation events with the resultant implementation of timely, evidence-based management.

Rescue thrombolysis for medium vessel occlusion (RESCUE-TNK): Rationale and design of a phase 2 randomized trial

Background

The best reperfusion strategy for medium-sized vessel occlusion (MeVO) is not well established. Given the proven treatment effect of intra-arterial thrombolysis in patients with large vessel occlusion (LVO), we hypothesized that intra-arterial tenecteplase (TNK) could increase the recanalization rate of MeVO and thus improve clinical outcome.

Aims

To explore the safety and efficacy of intra-arterial TNK in patients with MeVO.

Sample size estimates

A maximum of 80 patients are required to test the superiority hypothesis, using power = 80% and α = 0.025 to conduct the one-sided test.

Design

Rescue treatment for mEdium veSsel oCclUsion by intra-artErial TNK (RESCUE-TNK) is a pilot, randomized, open-label, blinded end point, and multicenter trial. Eligible patients including primary MeVO as detected by the first DSA examination or secondary MeVO after endovascular treatment (EVT) for LVO will be assigned into the experimental group and control group as a ratio of 1:1. The experimental group will be treated with intra-arterial TNK (0.2–0.3 mg/min, for 20–30 min) via a microcatheter placed proximal to the site of occlusion, and the control group will be treated with routine therapy. Both groups of patients will be given standard stroke care based on the guidelines.

Outcome

The primary efficacy end point is successful recanalization of MeVO, defined as the expanded treatment in cerebral ischemia (eTICI) score 2b67-3 after the procedure, while the primary safety end point is symptomatic intracranial hemorrhage (sICH), defined as National Institutes of Health Stroke Scale score increase ≥4 caused by intracranial hemorrhage within 24 (−6/+24) hours after randomization.

Conclusion

The results of RESCUE-TNK will provide evidence for the efficacy and safety of intra-arterial TNK in the recanalization of patients with MeVO.

Thrombolysis for acute ischaemic stroke: current status and future perspectives

Alteplase is currently the only approved thrombolytic agent for treatment of acute ischaemic stroke, but interest is burgeoning in the development of new thrombolytic agents for systemic reperfusion with an improved safety profile, increased efficacy, and convenient delivery. Tenecteplase has emerged as a potential alternative thrombolytic agent that might be preferred over alteplase because of its ease of administration and reported efficacy in patients with large vessel occlusion. Ongoing research efforts are also looking at potential improvements in recanalisation with the use of adjunct therapies to intravenous thrombolysis. New treatment strategies are also emerging that aim to reduce the risk of vessel reocclusion after intravenous thrombolysis administration. Other research endeavors are looking at the use of intra-arterial thrombolysis after mechanical thrombectomy to induce tissue reperfusion. The growing implementation of mobile stroke units and advanced neuroimaging could boost the number of patients who can receive intravenous thrombolysis by shortening onset-to-treatment times and identifying patients with salvageable penumbra. Continued improvements in this area will be essential to facilitate the ongoing research endeavors and to improve delivery of new interventions.

Recanalization Rate and Clinical Outcomes of Intravenous Tissue Plasminogen Activator Administration for Large Vessel Occlusion Stroke Patients

OBJECTIVE

Stroke caused from large vessel occlusion (LVO) has emerged as the most common stroke subtype worldwide. Intravenous tissue plasminogen activator administration (IV-tPA) and additional intraarterial thrombectomy (IA-Tx) is regarded as standard treatment. In this study, the authors try to find the early recanalization rate of IV-tPA in LVO stroke patients.

METHODS

Total 300 patients undertook IA-Tx with confirmed anterior circulation LVO, were analyzed retrospectively. Brain computed tomography angiography (CTA) was the initial imaging study and acute stroke magnetic resonance angiography (MRA) followed after finished IV-tPA. Early recanalization rate was evaluated by acute stroke MRA within 2 hours after the IV-tPA. In 167 patients undertook IV-tPA only and 133 non-recanalized patients by IV-tPA, additional IA-Tx tried (IV-tPA + IA-Tx group). And 131 patients, non-recanalized by IV-tPA (IV-tPA group) additional IA-Tx recommend and tried according to the patient condition and compliance.

RESULTS

Early recanalization rate of LVO after IV-tPA was 12.0% (36/300). In recanalized patients, favorable outcome (modified Rankin Scale, 0-2) was 69.4% (25/36) while it was 32.1% (42/131, p<0.001) in non-recanalized patients. Among 133 patients, nonrecanalized after intravenous recombinant tissue plasminogen activator and undertook additional IA-Tx, the clinical outcome was better than not undertaken additional IA-Tx (favorable outcome was 42.9% vs. 32.1%, p=0.046). Analysis according to the perfusion/diffusion (P/D)-mismatching or not, in patient with IV-tPA with IA-Tx (133 patients), favorable outcome was higher in P/ D-mismatching patient (52/104; 50.0%) than P/D-matching patients (5/29; 17.2%; p=0.001). Which treatment tired, P/D-mismatching was favored in clinical outcome (iv-tPA only, p=0.008 and IV-tPA with IA-Tx, p=0.001).

CONCLUSION

The P/D-mismatching influences on the recanalization and clinical outcomes of IV-tPA and IA-Tx. The authors would like to propose that we had better prepare IA-Tx when LVO is diagnosed on initial diagnostic imaging. Furthermore, if the patient shows P/D-mismatching on MRA after IV-tPA, additional IA-Tx improves treatment results and lessen the futile recanalization.

Intraarterial urokinase for thrombus migration after mechanical thrombectomy for large vessel ischemic stroke

BACKGROUND

Achieving rapid and complete reperfusion is the ultimate purpose for ischemic stroke with large vessel occlusion (LVO). Although mechanical thrombectomy (MT) had been a proverbially important procedure, medium vessel occlusion (MeVO) with thrombus migration can sporadically occur after MT. Moreover, the safe and effective approach for such had been unknown. We reported thrombolysis with intraarterial urokinase for MeVO with thrombus migration after MT.

METHODS

We included 122 patients who were treated by MT with LVO stroke at our institution between April 2019 and March 2021. Of 26 patients (21.3%) who developed MeVO with thrombus migration after MT, 11 (9.0%) underwent additional MT (MT group) and 15 (12.3%) received intraarterial urokinase (UK group). The procedure time; angiographically modified Treatment in Cerebral Ischemia Scale (mTICI); functional independence, which was defined as modified Rankin Scale 0-2, on day 30 or upon discharge; and symptomatic and asymptomatic intracerebral hemorrhage (ICH) were compared between the UK and MT groups.

RESULTS

The procedure time, mTICI, and asymptomatic ICH did not significantly differ between the groups. In the UK group, 8 of 15 (53.3%) patients obtained functional independence, and the functional independence rate was significantly higher in the UK group than in the MT group (p < 0.05). Symptomatic ICH did not occur in the UK group, and its incidence was significantly smaller than that in the MT group (p < 0.05).

CONCLUSION

The results of this study suggest that intraarterial urokinase for MeVO with thrombus migration after MT may safely improve angiographic reperfusion.

Intra-arterial thrombolytics during endovascular thrombectomy for acute ischaemic stroke in the MR CLEAN Registry

INTRODUCTION

The efficacy and safety of local intra-arterial (IA) thrombolytics during endovascular thrombectomy (EVT) for large-vessel occlusions is uncertain. We analysed how often IA thrombolytics were administered in the Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands (MR CLEAN) Registry, whether it was associated with improved functional outcome and assessed technical and safety outcomes compared with EVT without IA thrombolytics.

METHODS

In this observational study, we included patients undergoing EVT for an acute ischaemic stroke in the anterior circulation from the MR CLEAN Registry (March 2014-November 2017). The primary endpoint was favourable functional outcome, defined as an modified Rankin Scale score ≤2 at 90 days. Secondary endpoints were reperfusion status, early neurological recovery and symptomatic intracranial haemorrhage (sICH). Subgroup analyses for IA thrombolytics as primary versus adjuvant revascularisation attempt were performed.

RESULTS

Of the 2263 included patients, 95 (4.2%) received IA thrombolytics during EVT. The IA thrombolytics administered were urokinase (median dose, 250 000 IU (IQR, 1 93 750-2 50 000)) or alteplase (median dose, 20 mg (IQR, 12-20)). No association was found between IA thrombolytics and favourable functional outcome (adjusted OR (aOR), 1.16; 95% CI 0.71 to 1.90). Successful reperfusion was less often observed in those patients treated with IA thrombolytics (aOR, 0.57; 95% CI 0.36 to 0.90). The odds of sICH (aOR, 0.82; 95% CI 0.32 to 2.10) and early neurological recovery were comparable between patients treated with and without IA thrombolytics. For primary and adjuvant revascularisation attempts, IA thrombolytics were more often administered for proximal than for distal occlusions. Functional outcomes were comparable for patients receiving IA thrombolytics as a primary versus adjuvant revascularisation attempt.

CONCLUSION

Local IA thrombolytics were rarely used in the MR CLEAN Registry. In the relatively small study sample, no statistical difference was observed between groups in the rate of favourable functional outcome or sICH. Patients whom required and underwent IA thrombolytics were patients less likely to achieve successful reperfusion, probably due to selection bias.

Key design elements of successful acute ischemic stroke treatment trials

PURPOSE

We review key design elements of positive randomized controlled trials (RCTs) in acute ischemic stroke (AIS) treatment and summarize their main characteristics.

METHOD

We searched Medline, Pubmed and Cochrane databases for positive RCTs in AIS treatment. Trials were included if (1) they had a randomized controlled design, with (at least partial) blinding for endpoints, (2) they tested against placebo (or on top of standard therapy in a superiority design) or against approved therapy; (3) the protocol was registered and/or published before trial termination and unblinding (if required at study commencement); (4) the primary endpoint was positive in the intention to treat analysis; and (5) the study findings led to approval of the investigational product and/or high ranked recommendations. A topical approach was used, therefore the findings were summarized as a narrative review.

FINDINGS

Seventeen positive RCTs met the inclusion criteria. The majority of trials included less than 1000 patients (n = 15), had highly selective inclusion criteria (n = 16), used the modified Rankin score as a primary endpoint (n = 15) and had a frequentist design (n = 16). Trials tended to be national (n = 12), investigator-initiated and performed with public funding (n = 11).

DISCUSSION

Smaller but selective trials are useful to identify efficacy in a particular subgroup of stroke patients. It may also be of advantage to limit the number of participating countries and centers to avoid heterogeneity in stroke management and bureaucratic burden.

CONCLUSION

The key characteristics of positive RCTs in AIS treatment described here may assist in the design of further trials investigating a single intervention with a potentially high effect size.

Intra-arterial tenecteplase is safe and may improve the first-pass recanalization for acute ischemic stroke with large-artery atherosclerosis: the BRETIS-TNK trial

Background and purpose

The first-pass recanalization of endovascular treatment (EVT) is closely correlated with clinical outcome of patients with large vessel occlusion (LVO) stroke. The aim of the study was to explore whether intra-arterial tenecteplase (TNK) during the first pass of EVT can increase first-pass successful reperfusion and improve the neurological outcome in AIS-LVO patients.

Materials and methods

The BRETIS-TNK trial (ClinicalTrials.gov Identifier: NCT04202458) was a prospective, single-arm, single center study. Twenty-six eligible AIS-LVO patients with large-artery atherosclerosis etiology were consecutively enrolled from December 2019 to November 2021. Intra-arterial TNK (4 mg) after microcatheter navigation through the clot was administered, followed by TNK (0.4  mg/min) given continuously for 20  min after the first retrieval attempt of EVT without confirmation of the reperfusion status by DSA. The 50 control patients comprised of a historical cohort before the BRETIS-TNK trial (from March 2015 to November 2019). Successful reperfusion was defined as modified Thrombolysis In Cerebral Infarction (mTICI) ≥2b.

Results

The first-pass successful reperfusion rate was higher in the BRETIS-TNK vs. control group (53.8% vs. 36%, p = 0.14), and the difference became statistically significant after propensity score matching (53.8% vs. 23.1%, p = 0.03). There was no difference in symptomatic intracranial hemorrhage between the BRETIS-TNK and control groups (7.7% vs. 10.0%, p = 0.92). There was a trend toward higher proportion of functional independence at 90 days in the BRETIS-TNK comparing with the control group (50% vs. 32%, p = 0.11).

Conclusion

This is the first study to report that intra-arterial TNK during the first pass of EVT seems safe and feasible in AIS-LVO patients.

Motor sequela of adult and pediatric stroke: Imminent losses and ultimate gains

Stroke is the leading cause of neurological disability in the United States and worldwide. Remarkable advances have been made over the past 20 years in acute vascular treatments to reduce infarct size and improve neurological outcome. Substantially less progress has been made in the understanding and clinical approaches to neurological recovery after stroke. This chapter reviews the epidemiology, bedside examination, localization approaches, and classification of stroke, with an emphasis on motor stroke presentations and management, and promising research approaches to enhancing motor aspects of stroke recovery.

Acute ischaemic stroke: recent advances in reperfusion treatment

During the last 5–7 years, tremendous progress was achieved in the reperfusion treatment of acute ischaemic stroke during its first few hours from symptom onset. This review summarizes the latest evidence from randomized clinical trials and prospective registries with a focus on endovascular treatment using stent retrievers, aspiration catheters, thrombolytics, and (in selected patients) carotid stenting. Novel approaches in prehospital (mobile interventional stroke teams) and early hospital (direct transfer to angiography) management are described, and future perspectives (‘all-in-one’ laboratories with angiography and computed tomography integrated) are discussed. There is reasonable chance for patients with moderate-to-severe acute ischaemic stroke to survive without permanent sequelae when the large-vessel occlusion is removed by means of modern pharmaco-mechanic approach. Catheter thrombectomy is now the golden standard of acute stroke treatment. The role of cardiologists in stroke is expanding from diagnostic help (to reveal the cause of stroke) to acute therapy in those regions where such up-to-date Class I. A treatment is not yet available.

Endovascular thrombectomy and intravenous alteplase in patients with acute ischemic stroke due to large vessel occlusion: A clinical practice guideline

AIM

Whether or not use of intravenous alteplase in combination with endovascular thrombectomy (EVT) improves outcomes versus EVT alone, for acute stroke patients with large vessel occlusion presenting directly to a comprehensive stroke center, is uncertain.

METHODS

Six randomized trials exploring this issue were published, and we synthesized this evidence to inform a rapid guideline based on the Guidelines International Network principles and guided by the GRADE approach.

RESULTS

We enlisted an international panel that included 4 patient partners and 1 caregiver, individuals from 6 countries. The panel considered low certainty evidence that EVT alone, relative to EVT with intravenous alteplase, possibly results in a small decrease in the proportion of patients that achieve functional independence and possibly a small increase in mortality. Both effect estimates were downgraded twice due to very serious imprecision. The panel also considered moderate certainty evidence that EVT alone probably decreases symptomatic intracranial hemorrhage, versus EVT with alteplase, and combination therapy was more costly than EVT alone. As a result of the low certainty for improved recovery without impairment and mortality for combination therapy versus EVT alone, and moderate certainty for increased harm with combination therapy, the panel made a weak recommendation in favor of EVT alone for stroke patients eligible for both treatments, and initially presenting directly to a comprehensive stroke center that provides both treatments.

CONCLUSIONS

Consistent with this weak recommendation, optimal patient management will likely often include co-treatment with intravenous alteplase, depending on local circumstances and patient presentation.

Approaches to and outcomes of intra-arterial tPA in embolectomy for large vessel occlusion

INTRODUCTION

Intra-arterial tissue plasminogen activator (IA tPA) is sometimes used in conjunction with aspiration catheters and stentrievers to achieve recanalization in endovascular thrombectomy (ET) for large vessel occlusion (LVO). Reports of safety and efficacy of this approach are limited by technical heterogeneity and sample size.

METHODS

We retrospectively reviewed a data set of patients undergoing ET for LVO between August 2017 and September 2020 to identify those that received IA tPA. IA tPA usage, timing and dosage was at the discretion of the operative neurosurgeon. We identified three broad categories of IA tPA administration: (1) adjunctive with the first pass; (2) salvage with subsequent passes after first pass achieved incomplete revascularization; and (3) post-thrombectomy residual distal occlusions. Univariate and multivariate logistic regression were performed to test associations with recanalization, hemorrhage, and functional independence.

RESULTS

Among 271 patients, 158 (58%) patients had IA tPA, of which 83 received adjuvant IA tPA, 60 received salvage IA tPA, and 15 received post-thrombectomy IA tPA for distal occlusions. There were no differences in demographics, stroke etiology and premorbid medications between these groups. Patients receiving salvage IA tPA had longer times from groin access to recanalization and more passes, as expected. On multivariate analysis neither adjunctive nor salvage IA tPA was significantly associated with recanalization, post-operative hemorrhage, or functional outcomes. On univariate analysis, patients receiving salvage IA tPA had lower rates of TICI 3 or 2b revascularization (80% vs. 89% adjunctive and 92% no IA tPA, p =  0.003) and higher rates of any postoperative hemorrhage (33% vs. 22% adjunctive and 19% no IA tPA, p =  0.003).

CONCLUSIONS

In this retrospective, single-institution series, IA tPA used adjunctively or as salvage therapy in ET for LVO was not associated with recanalization, post-operative hemorrhage, or functional outcomes, suggesting IA tPA is an available modality that can be utilized in cases of recalcitrant clots.

Distribution-Free Approach to the Design and Analysis of Randomized Stroke Trials With the Modified Rankin Scale

BACKGROUND

Many methods have been suggested for analyzing the modified Rankin Scale (mRS). However, there lacks a unified approach to analysis and sample size determination that properly uses the ordinal nature of the data. We propose a simple method for CI estimation and corresponding sample size determination.

METHODS

We quantify treatment effect by the win probability (WinP) that a randomly selected patient in the treatment group has an equal or a better mRS score than a patient in the control group. Thus, a win probability of 0.5 means no effect, likened to a draw in competitive sports. We estimate the win probability and its SE based on the ranks of mRS scores, where tied scores are handled by average ranks. Corresponding methods for hypothesis testing, CI estimation, and sample size determination are derived. The methods are evaluated with a simulation study based on real data from 10 randomized stroke trials that used mRS as the outcome measure.

RESULTS

Simulation results demonstrated that the methods performed very well in terms of CI coverage, tail errors, and assurance to achieving the prespecified precision. Because the methods are very simple, we implemented them in an Excel spreadsheet, requiring only user inputs on frequencies of mRS scores in 2 comparison groups.

CONCLUSIONS

Sound statistical methods are important for the success of randomized stroke trials. The proposed methods and associated spreadsheet should prove useful for stroke researchers in the planning and analysis of randomized trials. Meta-analysis has also been made easy for trials with ordinal scores.

Intra-Arterial Thrombolysis Vs. Mechanical Thrombectomy in Acute Minor Ischemic Stroke Due to Large Vessel Occlusion

Background

The efficacy and safety of mechanical thrombectomy (MT) in acute large vessel occlusion (LVO) patients with minor stroke (NIHSS ≤ 5) remains undetermined. We aimed to compare the efficacy and safety of intra-arterial thrombolysis (IAT) alone vs. MT for LVO patients with minor stroke.

Methods

Patients were selected from the Acute Ischemic Stroke Cooperation Group of Endovascular Treatment (ANGEL) registry, a prospective multicenter registry study, and divided into MT and IAT alone groups. We compared the outcome measures between the two groups, including 90-day functional outcome evaluated by the modified Rankin Scale (mRS), the final recanalization level, intracranial hemorrhage, and mortality within 90-days by logistic regression models with adjustment. Besides the conventional multivariable analysis, we performed a sensitivity analysis by adjusting the propensity score to confirm our results. The propensity score was derived using a logistic regression model.

Results

Of the 120 patients, 63 received IAT alone and 57 received MT as the first-line treatment strategy. As compared to MT group, patients in the IAT alone group were associated with a higher chance of 90-day mRS 0-2 [93.7% vs. 71.9%, odds ratio (OR) = 4.75, 95% confidence interval (CI): 1.20–18.80, P = 0.027], a high chance of 90-day mRS 0-3 (96.8% vs. 86.7%, OR = 11.35, 95% CI: 1.93–66.86, P = 0.007), a shorter median time from puncture to recanalization (PTR) (60 min vs. 100 min, β = −63.70, 95% CI: −81.79– −45.61, P < 0.001), a lower chance of any intracranial hemorrhage (ICH) within 48 h (3.2% vs. 19.3%, OR = 0.15, 95% CI: 0.03–0.79, P = 0.025), and a lower chance of mortablity within 90 days (1.6% vs. 9.2%, OR = 0.05, 95% CI: 0.01–0.57, P = 0.016). Similarly, the sensitivity analysis showed the robustness of the primary analysis.

Conclusions

Compared with MT, IAT may improve 90-day clinical outcomes with decreased ICH rate and mortality in LVO patients with minor stroke.

Early hyperchloremia and outcomes after acute ischemic stroke

OBJECTIVE

Based on the relationship between hyperchloremia and mortality in critically ill patients, we investigated the effect of early hyperchloremia on 90-day outcomes in acute ischemic stroke patients.

MATERIALS AND METHODS

Acute ischemic stroke patients recruited within 5 h of symptom onset were analyzed. Hyperchloremia (defined as 110 mmol/L or greater) at either baseline, or 24, or 48 h after randomization was identified and classified as one occurrence or two or more occurrences. Logistic regression analyses were performed to determine the effects of hyperchloremia on: favorable outcomes (defined by a National Institutes of Health Stroke Scale and/or modified Rankin scale scores of 0-1) at 90-day, death or disability at 90-day, and death within 90-day after accounting for potential confounders.

RESULTS

Among the total of 1275 patients, one and two or more occurrence of hyperchloremia within 48 h were seen in 191 patients and 108 patients, respectively. Compared with patients without hyperchloremia, patients with two or more occurrences of hyperchloremia at significantly higher odds of lack of favorable outcomes (odds ratio 3.0, 95% confidence interval 1.8-5.1) and death or disability (odds ratio 2.6, 95% confidence interval 1.6-4.1) at 90-day after adjustment for age, National Institutes of Health Stroke Scale score strata (6-9, 10-19, ≥ 20), study intervention, initial SBP, and intra-arterial treatment.

CONCLUSIONS

The independent association between sustained hyperchloremia and lack of favorable outcomes at 90-day suggest that avoidance of hyperchloremia may reduce the rate of lack of favorable outcomes and death or disability in patients with acute ischemic stroke.

Factors affecting mechanical thrombectomy outcome in acute ischemic stroke patients: an Egyptian sample

Background

Stroke constitutes a major health problem worldwide, nowadays endovascular treatment is considered to be a standard of care in acute ischemic stroke patients with large vessel occlusion, accurate prediction of outcome of thrombectomy is essential for health care providers, patients and families. We studied different clinical and radiological variables that could predict functional outcome in stroke patients after thrombectomy. Thirty-four consecutive ischemic stroke patients were included, received intravenous tissue plasminogen activator (iv-tpa), then mechanical thrombectomy was done. Patients were clinically assessed at admission with National Institute of Health Stroke Scale (NIHSS) then evaluated by the Alberta Stroke Program early computerized tomography (CT) score (ASPECTS), clot burden scale (CBS) and collateral score (CS) in multiphase computerized tomography angiography (CTA) then good and poor outcomes at 3 months were defined by Modified Rankin Scale (MRS) of 0–2 and 3–6 points, respectively.

Results

Factors associated with good outcome (MRS 0–2) were lower admission NIHSS score (p < 0.037), small infarct core aspects ≥ 6 (p < 0.001), low clot burden (CBS 7–10) (p = 0.046) good collaterals (2–3) (p = 0.038) and absence of post-procedure hemorrhage (p < 0.0005).

Conclusions

Low admission NIHSS score, absence of post-procedure hemorrhage, small infarct core, low clot burden and good collaterals are reliable factors for good clinical outcome.

Patient and procedure selection for mechanical thrombectomy: Toward personalized medicine and the role of artificial intelligence

Mechanical thrombectomy (MT) for ischemic stroke due to large vessel occlusion is standard of care. Evidence-based guidelines on eligibility for MT have been outlined and evidence to extend the treatment benefit to more patients, particularly those at the extreme ends of a stroke clinical severity spectrum, is currently awaited. As patient selection continues to be explored, there is growing focus on procedure selection including the tools and techniques of thrombectomy and associated outcomes. Artificial intelligence (AI) has been instrumental in the area of patient selection for MT with a role in diagnosis and delivery of acute stroke care. Machine learning algorithms have been developed to detect cerebral ischemia and early infarct core, presence of large vessel occlusion, and perfusion deficit in acute ischemic stroke. Several available deep learning AI applications provide ready visualization and interpretation of cervical and cerebral arteries. Further enhancement of AI techniques to potentially include automated vessel probe tools in suspected large vessel occlusions is proposed. Value of AI may be extended to assist in procedure selection including both the tools and technique of thrombectomy. Delivering personalized medicine is the wave of the future and tailoring the MT treatment to a stroke patient is in line with this trend.

Improving Visualization Methods of Utility-Weighted Disability Outcomes for Stroke Trials

Background

The modified Rankin Scale (mRS) is the most common endpoint in acute stroke trials, but its power is limited when analyzed dichotomously and its indication of effect size is challenging to interpret when analyzed ordinally. To address these issues, the utility-weighted-mRS (UW-mRS) has been developed as a patient-centered, linear scale. However, appropriate data visualizations of UW-mRS results are needed, as current stacked bar chart displays do not convey crucial utility-weighting information.

Design/Methods

Two UW-mRS display formats were devised: (1) Utility Staircase charts, and (2) choropleth-stacked-bar-charts (CSBCs). In Utility Staircase displays, mRS segment height reflects the utility value of each mRS level. In CSBCs, mRS segment color intensity reflects the utility of each mRS level. Utility Staircase and CSBC figures were generated for 15 randomized comparisons of acute ischemic/hemorrhagic stroke therapies, including fibrinolysis, endovascular reperfusion, blood pressure moderation, and hemicraniectomy. Display accuracy in showing utility outcomes was assessed with the Tufte-lie-factor and ease-of-use assessed by formal ratings completed by a panel of 4 neurologists and emergency physicians and one nurse-coordinator.

Results

The Utility Staircase and CSBC displays rapidly conveyed patient-centered valuation of trial outcome distributions not available in conventional ordinal stacked bar charts. Tufte-lie-factor (LF) scores indicated “substantial distortion” of utility-valued outcomes for 93% (14/15) of conventional stacked bar charts, vs. “no distortion” for all Utility Staircase and CSBC displays. Clinician ratings on the Figural Display Questionnaire indicated that utility information encoded in row height (Utility Staircase display) was more readily assimilated than that conveyed in segment hue intensity (CSBC), both superior to conventional stacked bar charts.

Conclusions

Utility Staircase displays are an efficient graphical format for conveying utility weighted–modified Rankin Scale primary endpoint results of acute stroke trials, and choropleth-stacked-bar-charts a good alternative. Both are more accurate in depicting quantitative, health-related quality of life results and preferred by clinician users for utility results visualization, compared with conventional stacked bar charts.

The End of Tissue-Type Plasminogen Activator's Reign?

Mechanical thrombectomy is a highly effective treatment for acute ischemic stroke caused by large-vessel occlusion in the anterior cerebral circulation, significantly increasing the likelihood of recovery to functional independence. Until recently, whether intravenous thrombolysis before mechanical thrombectomy provided additional benefits to patients with acute ischemic stroke-large-vessel occlusion remained unclear. Given that reperfusion is a key factor for clinical outcome in patients with acute ischemic stroke-large-vessel occlusion and the efficacy of both intravenous thrombolysis and mechanical thrombectomy is time-dependent, achieving complete reperfusion with a single pass should be the primary angiographic goal. However, it remains undetermined whether extending the procedure with additional endovascular attempts or local lytics administration safely leads to higher reperfusion grades and whether there are significant public health and cost implications. Here, we outline the current state of knowledge and research avenues that remain to be explored regarding the consistent therapeutic benefit of intravenous thrombolysis in anterior circulation strokes and the potential place of adjunctive intra-arterial lytics administration, including alternative thrombolytic agent place.

Efficacy and Safety of Recombinant Human Prourokinase in Acute Ischemic Stroke: A Phase IIa Randomized Clinical Trial

Recombinant human prourokinase (rhPro-UK) is a novel thrombolytic that has been approved to treat patients with acute myocardial infarction. However, the safety and efficacy of intravenous rhPro-UK in patients with acute ischemic stroke (AIS) has not been well established. We aimed to investigate the safety and preliminary efficacy of rhPro-UK in patients with AIS in a multi-center phase IIa trial setting. One hundred nineteen patients within 4.5 h of AIS onset were enrolled in this randomized, open-label, 23-center phase IIa clinical trial. Patients were randomly assigned to 35 mg (n = 40) or 50 mg (n = 39) intravenous rhPro-UK or 0.9 mg/kg recombinant tissue plasminogen activator (r-tPA; n = 40). The primary endpoint was functional independence defined as a modified Rankin scale (mRS) score of 0 or 1 at 90 days. The secondary outcome was early neurological improvement defined as a reduction of ≥ 4 points on the National Institutes of Health Stroke Scale (NIHSS) score from baseline to 24 h after drug administration. Safety endpoints included death due to any cause, symptomatic intracerebral hemorrhage (sICH), and other serious adverse events (SAEs). The proportion of patients with an mRS score of ≤ 1 at 90 days did not differ significantly among three groups (35 mg rhPro-UK: 55.56% vs. 50 mg rhPro-UK: 57.89% vs. vs. r-tPA: 52.63%; P = 0.92). The rates of treatment response, referring to early neurological improvement, were similar among these three groups (36.11% vs. 31.58% vs. 28.95%, respectively; P = 0.85). There was no difference in mortality at 90 days or in the rate of other SAEs among the three groups. One patient in the 50 mg rhPro-UK group suffered sICH. While neither the primary efficacy outcomes nor safety profile differed significantly among the low, high rhPro-UK and control groups, it is a logical step to further test the low-dose rhPro-UK group versus the control group in a well-powered phase III study.Trial Registration: http://www.chictr.org.cn . Identifier: ChiCTR1800016519. Date of registration: June 6 2018.

Investigational drugs for ischemic stroke: what's in the clinical development pipeline for acute phase and prevention?

INTRODUCTION

Stroke is a leading cause of disability and mortality and its burden expected to increase. The only approved drug for acute ischemic stroke is the intravenous thrombolytic alteplase. The risk of bleeding complications is one of the reasons for the undertreatment of eligible patients. Numerous drugs are currently being developed to improve safety-efficacy.

AREAS COVERED

We reviewed literature from January 1^st, 2000, to 15^th January 2022 for the development and testing of novel drugs with the aim of targeting treatment at prevention of ischemic stroke: PubMed, MEDLINE, Google Scholar, and ClinicalTrial.gov.

EXPERT OPINION

The pathophysiology of ischemic stroke involves multiple pathways causing cerebral artery obstruction and brain tissue ischemia. Data suggest that tenecteplase is a more promising fibrinolytic agent with a superior efficacy-safety profile, compared to the currently approved alteplase. Current guidelines consider a short-term cycle of mannitol or hypertonic saline to be advisable in patients with space-occupying hemispheric infarction. Regarding primary and secondary prevention, research is primarily focused on identifying mechanisms to improve the safety-efficacy profile using a "hemostasis-sparing" approach. Further evaluation on those agents that have already shown promise for their risk/benefit profiles, would benefit greatly a neurologist's capacity to successfully prevent and treat ischemic stroke patients.

Outcomes of endovascular treatment for acute ischaemic stroke in Mater Dei Hospital, Malta

INTRODUCTION

The aim of this study was to assess the outcomes of endovascular treatment for acute ischaemic stroke in Mater Dei Hospital, Malta and compare them with international data.

METHODS

A prospective review of all patients who underwent mechanical thrombectomy from 2015 to the end of 2019 was performed. Eligible patients had large vessel occlusion confirmed on computed tomography angiography. Demographical data, the National Institutes of Health stroke scale at presentation, endovascular procedure details and process times were analysed. The thrombolysis in cerebral infarction score was used to assess the degree of reperfusion. A thrombolysis in cerebral infarction score of 2b-3 was considered as successful recanalisation. Functional outcome (modified Rankin scale score) and mortality at 90 days were measured. Functional independence was defined as a modified Rankin scale score of 2 or less.

RESULTS

A total of 132 patients underwent endovascular treatment, one patient was excluded due to incomplete data. The mean age was 71 (range 25-94) years, and the mean National Institutes of Health stroke scale at presentation was 14. Of the 131 patients treated, 69 received intravenous thrombolysis. Successful recanalisation (thrombolysis in cerebral infarction score 2b-3) was achieved in 80% of patients (105/131); 53% of patients (69/131) achieved functional independence at 90 days, with a mortality of 21% at 90 days. Symptomatic intracranial haemorrhage was recorded in 16 patients (12%) There was a statistical difference in the functional independence and mortality rate in favour of the successful recanalisation group.

CONCLUSION

Our data are consistent with a favourable clinical outcome after successful recanalisation. Service in Malta is achieving favourable outcomes for patients treated with mechanical thrombectomy for acute ischaemic stroke.

Clinical Imaging of the Penumbra in Ischemic Stroke: From the Concept to the Era of Mechanical Thrombectomy

The ischemic penumbra is defined as the severely hypoperfused, functionally impaired, at-risk but not yet infarcted tissue that will be progressively recruited into the infarct core. Early reperfusion aims to save the ischemic penumbra by preventing infarct core expansion and is the mainstay of acute ischemic stroke therapy. Intravenous thrombolysis and mechanical thrombectomy for selected patients with large vessel occlusion has been shown to improve functional outcome. Given the varying speed of infarct core progression among individuals, a therapeutic window tailored to each patient has recently been proposed. Recent studies have demonstrated that reperfusion therapies are beneficial in patients with a persistent ischemic penumbra, beyond conventional time windows. As a result, mapping the penumbra has become crucial in emergency settings for guiding personalized therapy. The penumbra was first characterized as an area with a reduced cerebral blood flow, increased oxygen extraction fraction and preserved cerebral metabolic rate of oxygen using positron emission tomography (PET) with radiolabeled O₂. Because this imaging method is not feasible in an acute clinical setting, the magnetic resonance imaging (MRI) mismatch between perfusion-weighted imaging and diffusion-weighted imaging, as well as computed tomography perfusion have been proposed as surrogate markers to identify the penumbra in acute ischemic stroke patients. Transversal studies comparing PET and MRI or using longitudinal assessment of a limited sample of patients have been used to define perfusion thresholds. However, in the era of mechanical thrombectomy, these thresholds are debatable. Using various MRI methods, the original penumbra definition has recently gained a significant interest. The aim of this review is to provide an overview of the evolution of the ischemic penumbra imaging methods, including their respective strengths and limitations, as well as to map the current intellectual structure of the field using bibliometric analysis and explore future directions.