Endovascular therapy after intravenous t-PA versus t-PA alone for stroke

Association between stress hyperglycemia ratio with short-term and long-term mortality in critically ill patients with ischemic stroke

AIMS

Hyperglycemia on admission is associated with poor prognosis in ischemic stroke (IS) patients. We aimed to investigate the relationship between stress hyperglycemia ratio (SHR) and short-term or long-term mortality in IS patients in the ICU and to explore whether this relationship is influenced by diabetes status.

MATERIALS AND METHODS

We collected patients with severe IS requiring ICU admission in the Medical Information Mart for Intensive Care (MIMIC-IV) database and calculated SHR. Outcomes included 30-day, 90-day, and 1-year mortality. The association between SHR and mortality in patients with critical IS was elucidated using Multivariate Cox regression and subgroup analysis for diabetes.

RESULTS

A total of 1376 patients were recruited. After adjusting for potential confounders, patients in the third and fourth quartiles had a significantly increased risk of death at 30 days, 90 days, and 1 year compared to the first quartile of SHR (Q3 vs. Q1: HR 1.56-1.80, all p < 0.02; Q4 vs. Q1: HR 1.75-2.15, all p < 0.001; all p for trend < 0.001). In addition, the highest quartile of SHR was significantly associated with short-term or long-term mortality compared with the first quartile, regardless of diabetes status.

CONCLUSIONS

Our results suggest that stress hyperglycemia, defined by the glucose/HbA1c ratio, is associated with increased short-term and long-term mortality in patients with ischemic stroke, independent of the patient's diabetes status.

Prehospital neurologic assessment using mobile phones: Comparison between neurologists and emergency physicians

BACKGROUND

Ambulance-based telestroke may be a promising solution to improving stroke care. We assessed the technical feasibility and reliability of prehospital evaluations using commercial mobile phones with fifth-generation wireless communication technology.

METHODS

Six standardized patients portrayed scripted stroke scenarios during ambulance transport in an urban city and were remotely evaluated by independent raters using tablets (three neurologists and three emergency physicians) in a hospital, assisted by paramedics (trained in National Institute of Health Stroke Scale [NIHSS] assessment) in the ambulance; commercial cellular networks were utilized for videoconferencing transmission. The primary outcomes were mean difference (MD) and correlation of NIHSS scores between the face-to-face and remote assessments. We also examined the Bland-Altman plot for itemized NIHSS components, and Kaplan-Meier curves were used to compare the differences in the duration of the two evaluations between neurologists and emergency physicians.

RESULTS

We conducted 32 ambulance runs and successfully completed all NIHSS examinations. No significant difference was found between the face-to-face and remote evaluations (MD, 0.782; 95% confidence interval [CI], -0.520-0.395). The correlation of NIHSS scores between the two methods was 0.994 (95% CI, 0.945-1.026), and three items exhibited the highest frequency of runs, with score differences between the two methods. There were no significant differences between neurologists and emergency physicians in the mean evaluation duration and NIHSS scores for the two methods.

CONCLUSION

Prehospital evaluation using commercial mobile phones with fifth-generation wireless communication technology is feasible and reliable during ambulance transport in urban areas. Emergency physicians and neurologists performed similarly in stroke evaluations.

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.

Randomised study of bailout intracranial angioplasty following thrombectomy for acute large vessel occlusion (ANGEL-REBOOT): protocol of a multicentre randomised controlled trial

RATIONALE

Unsuccessful thrombectomy of acute large vessel occlusions (LVOs) has been associated with unfavourable outcomes. Multiple randomised controlled trials (RCTs) have reported a failure rate of 12%-41% for thrombectomy procedures. Various factors contribute to failed thrombectomy, including technical difficulties in accessing the occlusion, unsuccessful thrombus retrieval, thrombotic reocclusion and pre-existing intracranial atherosclerotic stenosis. Although some studies have explored balloon dilation or permanent stenting as rescue intracranial angioplasty for failed thrombectomy in individual cases, there is currently no evidence from RCTs on this specific topic.

AIM

To evaluate the potential superiority of bailout angioplasty over standard treatment in cases of unsuccessful recanalisation (eTICI 0 to 2a) or residual severe stenosis (>70%) after thrombectomy in acute LVO patients within 24 hours of stroke onset.

DESIGN

This study is a multicentre, prospective, randomised, controlled clinical trial designed by investigators. It compares bailout angioplasty with standard therapy and follows an open-label treatment approach while maintaining a blinded outcome assessment (PROBE design). Our objective is to allocate 348 patients in a 1:1 ratio to either receive bailout angioplasty as an intervention or standard therapy as a control, following unsuccessful thrombectomy.

OUTCOME

The main measure of interest is the modified Rankin Scale (mRS) Score, which will be assessed in a blinded manner at 90 (±14) days following randomisation. The primary effect size will be determined using ordered logistic regression to calculate the common OR, representing the shift on the six-category mRS Scale at the 90-day mark. Additionally, the safety outcomes will be evaluated, including symptomatic intracranial haemorrhage within 18-36 hours, severe procedure-related complications and mortality within 90 (±14) days, among others.

DISCUSSION

The ANGEL-REBOOT study aims to generate substantial evidence regarding the efficacy and safety of bailout intracranial angioplasty as a treatment option for patients with LVO who have experienced unsuccessful thrombectomy.

TRIAL REGISTRATION NUMBER

NCT05122286.

An optimization model for reducing thrombectomy center rotations while maintaining medical accessibility

BACKGROUND/PURPOSE

This study addresses the delicate balance between healthcare personnel burnout and medical accessibility in the context of endovascular thrombectomy (EVT) services in urban areas. We aimed to determine the minimum number of hospitals providing EVT on rotation each day without compromising patient access.

METHODS

Employing an optimization model, we developed shift schedules based on patient coverage rates and volumes during the pre-pandemic (2016-2018) and pandemic (2019-2021) periods. Starting with a minimum of two hospitals on duty per day, we gradually increased to a maximum of eight. Patient coverage rates, defined as the proportion of patients meeting bypass criteria and transported to rotating hospitals capable of EVT, were the primary outcomes. Sensitivity analyses explored the impact of varying patient transport intervals and accumulating patients over multiple years.

RESULTS

Results from 7024 patient records revealed patient coverage rates of 92.5% (standard deviation [SD] 2.8%) during the pre-pandemic and 91.4% (SD 2.8%) during the pandemic, with at least two rotating hospitals daily. No significant differences were observed between schedules based on the highest patient volume and coverage rate months. A patient coverage rate of 98.99% was achieved with four rotating hospitals per day during the pre-pandemic period, with limited improvement beyond this threshold. Changing patient transport intervals and accumulating patients over six years (p = 0.83) had no significant impact on coverage rates.

CONCLUSION

Our optimization model supports reducing the number of daily rotating hospitals by half while preserving a balance between patient accessibility and alleviating strain on medical teams.

Impact of Early Mobilization on Patients With Acute Ischemic Stroke Treated With Thrombolysis or Thrombectomy: A Randomized Controlled Trial

BACKGROUND

Early mobilization (EM) within 24 to 72 hours post-stroke may improve patients' performance and ability. However, after intravenous thrombolysis (IVT) or mechanical thrombectomy (MT), the increased risk of hemorrhagic complications impacts the implementation of early out-of-bed mobilization. Few studies have investigated EM after IVT or MT for acute ischemic stroke (AIS), and its impact in these patients is unknown.

OBJECTIVE

To investigate the effect of EM on AIS treated with IVT or MT.|.

METHODS

We recruited 122 patients with first AIS; 60 patients were treated with IVT, and 62 patients were treated with MT. For each IVT and MT cohort, the control groups received standard early rehabilitation, and the intervention groups received an EM protocol. The training lasted 30 minutes/day, 5 days/week until discharge.

MAIN OUTCOMES MEASURES

The effectiveness of the interventions was evaluated using the motor domain of the Functional Independence Measure (FIM-motor) and the Postural Assessment Scale for Stroke Patients (PASS) at baseline, 2-week, 4-week, and 3-month post-stroke, the Functional Ambulation Category 2-week post-stroke, and the total length of stay at the stroke center.

RESULTS

Both IVT and MT treatment groups showed improved FIM-motor and PASS scores over time; however, only the IVT EM group had significantly improved FIM-motor performance within 1 month after stroke than the control group. Conclusion. An EM protocol with the same intervention time and session frequency per day as in the standard care protocol was effective in improving the functional ability of stroke patients after IVT.

The role of innovative technologies in reducing health system inequity

The scarcity of Health Human Resources (HHR), regional disparities, and decentralized healthcare systems have profoundly affected health equity in Canada. Adequate HHR allocation is essential for equitable healthcare delivery, and the COVID-19 pandemic has revealed the importance of resilient and culturally diverse organizational HHR. Geography and infrastructure shortcomings aggravate healthcare equity. This study examines the role of innovative technologies in reducing inequity and provides four practice-based examples in different therapeutic areas. Long-term solutions such as collaborative networks, infrastructure improvements, and effective HHR planning can mitigate current challenges. However, in the short and medium terms, advanced medical technologies, digital health, and artificial intelligence can reduce health inequities by improving access, reducing disparities, optimizing resource utilization, and providing skill development opportunities for healthcare professionals.

Post-diffusion and perfusion magnetic resonance imaging of emboli to distal territories after endovascular thrombectomy

BACKGROUND AND PURPOSE

This study aimed to investigate the clinical outcomes of emboli to distal territories (EDT) after aspiration thrombectomy in patients with acute anterior circulation occlusion.

MATERIALS AND METHODS

From January 2016 to December 2022, all eligible patients who underwent endovascular treatment (EVT) due to acute anterior circulation occlusion were retrospectively reviewed. During this period, patients with EDT after EVT underwent magnetic resonance (MR) perfusion with angiography and diffusion-weighted imaging within 12 hours from recanalization. Hypoperfusion was defined as a Tmax value > 6-second volume.

RESULTS

Of the 104 eligible patients (65 males, median age 74 years), 79 (76.0 %; 2a: 19, 2b: 55, 2c: 5) had hypoperfusion on perfusion MR (PWI). Complete mismatch on diffusion-weighted imaging (DWI) of the hypoperfusion area was significantly higher in patients with successful recanalization than in patients with incomplete recanalization (58.3 % vs. 31.6 %, p = 0.0437). Of the 79 patients with hypoperfusion, 24 had EDT in the M2, 39 in the M3, and 16 in the M4. Complete mismatch on DWI and PWI was significantly higher in patients with a distal EDT (M3 or M4) than in patients with an M2 EDT (65.8 % vs. 20.8 %, p < 0.001).

CONCLUSIONS

EDT to the M3 or more distal branches after EVT had a higher rate of complete DWI-PWI mismatch on early follow-up MRI than EDT to M2.

Mechanism of action and neuroprotective role of nicorandil in ischemic stroke

Nicorandil is a dual mechanism anti-anginal agent that acts as a nitric oxide (NO) donor and a potassium (K+) channel opener. Recent studies have evaluated the effect of nicorandil on ischemic stroke. Neurons have a low tolerance to hypoxia and therefore the brain tissue is significantly vulnerable to ischemia. Current approved treatments for ischemic stroke are tissue plasminogen activators and clot retrieval methods. The narrow therapeutic time window and lack of efficacy in restoring the dying neurons urge researchers to develop an alternative approach. In the terminal stages of anoxia, K+ channels induce hyperpolarization in various types of neuronal cells, leading to decreased neuronal activity and the preservation of the brain's energy. Nicorandil can open these K+ channels and sustain the hyperpolarization phase, which may have a neuroprotective effect during hypoxia. Additionally, we review how nicorandil can improve overall stroke outcomes through its anti-inflammatory, anti-oxidative, and edema-reducing effects. One of the major components evaluated in stroke patients is blood pressure. Studies have demonstrated that the effect of nicorandil on blood pressure is related to both its K+ channel opening and NO donating mechanisms. Since both hypertension and hypotension need correction before stroke intervention, it's crucial to consider the role of nicorandil and its impact on blood pressure. Previously published studies indicate that the right dosage of nicorandil can improve cerebral blood flow without significant changes in hemodynamic profiles. In this review, we discuss how nicorandil may contribute to better stroke outcomes based on previously published literature and laboratory findings.

Rationale and design of Tenecteplase Reperfusion Therapy in Acute Ischaemic Cerebrovascular Events III (TRACE III): a randomised, phase III, open-label, controlled trial

BACKGROUND AND PURPOSE

Recombinant human TNK tissue-type plasminogen activator (rhTNK-tPA) was not inferior to alteplase for ischaemic stroke within 4.5 hours. Our study aimed to investigate the efficacy and safety of rhTNK-tPA in patients who had an ischaemic stroke due to large vessel occlusion (LVO) of anterior circulation beyond 4.5 hours.

METHODS AND DESIGN

Tenecteplase Reperfusion Therapy in Acute Ischaemic Cerebrovascular Events-III (TRACE III) is a multicentre, prospective, randomised, open-label, blind endpoint, controlled clinical trial. Patients who had an ischaemic stroke due to anterior circulation LVO (internal carotid artery, middle cerebral artery M1 and M2 segments) within 4.5-24 hours from last known well (including wake-up stroke and no witness stroke) and with salvageable tissue (ischaemic core volume <70 mL, mismatch ratio ≥1.8 and mismatch volume ≥15 mL) based on CT perfusion or MRI perfusion-weighted imaging (PWI) were included and randomised to rhTNK-tPA 0.25 mg/kg (single bolus) to a maximum of 25 mg or standard medical therapy. Specially, we will exclude patients who are intended for direct thrombectomy. All will be followed up for 90 days.

STUDY OUTCOMES

Primary efficacy outcome is modified Rankin Scale (mRS) score ≤1 at 90 days. Secondary efficacy outcomes include ordinal distribution of mRS at 90 days, major neurological improvement defined by a decrease ≥8 points compared with the initial deficit or a score ≤1 on the National Institutes of Health Stroke Scale (NIHSS) at 72 hours, mRS score ≤2 at 90 days, the rate of improvement on Tmax >6 s at 24 hours and NIHSS score change from baseline at 7 days. Safety outcomes are symptomatic intracerebral haemorrhage within 36 hours and mortality at 90 days.

DISCUSSION

TRACE III will provide evidence for the efficacy and safety of rhTNK-tPA in patients who had an ischaemic strokes due to anterior circulation LVO beyond 4.5 hours.

TRIAL REGISTRATION NUMBER

NCT05141305.

Mediation of long-pulsed ultrasound enhanced microbubble recombinant tissue plasminogen activator thrombolysis in a rat model of platelet-rich thrombus

Background

Ultrasound (US)-enhanced microbubble (MB) therapy has been investigated as a therapeutic technique to facilitate the thrombolysis for the treatment of pericardial and microvascular obstruction. This study sought to assess the therapeutic effects of long-pulsed US-assisted MB-mediated recombinant tissue plasminogen activator (rt-PA) thrombolysis in a rat model of platelet-rich thrombus.

Methods

Ferric chloride (10%) was used to induce total arterial occlusion before formation of platelet-rich thrombi. Therapeutic long-tone-burst US (1 MHz, 0.6 MPa, 1,000-µs pulse length) was used, and 2.9×109/mL of lipid MBs and 1 mg/mL of rt-PA were infused. Subsequently, 42 Sprague-Dawley (SD) male rats were randomly divided into seven groups: (I) control; (II) rt-PA; (III) high duty cycle US + MB; (IV) low duty cycle US + rt-PA; (V) high duty cycle US + rt-PA; (VI) low duty cycle US + rt-PA + MB; and (VII) high duty cycle US + rt-PA + MB. The recanalization grades were evaluated after 20 minutes' treatment.

Results

Compared to the control, there was significant improvement in recanalization in the US + rt-PA groups (P=0.01 vs. control), US (low duty cycle) + rt-PA + MB (P=0.003 vs. control) and US (high duty cycle) + rt-PA + MB (P<0.001 vs. control) groups, in which recanalization was successfully achieved in all rats.

Conclusions

Long-pulsed US-enhanced MB-mediated rt-PA thrombolysis offered a powerful approach in the treatment of platelet-rich thrombus.

Advancements in diagnostic and interventional radiology for stroke treatment: the path from trial to bedside through the pre-MR CLEAN, MR CLEAN, and MR CLEAN II eras

The stroke field is inevitably connected with imaging in which radiologists fulfill a central role. Our landmark MR CLEAN trial led to the implementation of baseline computed tomography angiography or magnetic resonance angiography in the acute stroke workup and subsequent endovascular treatment (EVT) for ischemic stroke patients with a large vessel occlusion in the anterior circulation, resulting in numerous patients worldwide currently being treated often successfully. A reversal of the pathophysiologic process behind an acute cerebrovascular event was made possible. Subsequently, in the MR CLEAN II trials, the clinical impact of both diagnostic and interventional radiologists remained a cornerstone of our research, which means value-based radiology. Within these MR CLEAN II trials, we proved that aspirin and heparin during EVT should be avoided due to increased symptomatic intracranial hemorrhage risk (MR CLEAN-MED). We concluded there is additional benefit of EVT in the 6-to-24-h window after stroke in the presence of good collaterals on baseline CTA (MR CLEAN-LATE). The impactful success of our stroke trials that changed many guidelines was mainly attributable to (1) the societal burden of the disease, with two thirds of patients dying or being independent at 3 months; (2) the fact that stroke is a common disease, (3) the relatively simple and pragmatic approach of the trials resembling real-world setting; (4) the acceleration of implementation in clinical practice facilitated by a structured approach to guideline development and conditional funding; and foremost (5) the excellent collaboration on a professional level between-disciplines, i.e., diagnostic radiologists, interventionalists, and neurologists.Critical relevance statement The MR CLEAN and MR CLEAN II trials have had tremendous impact on clinical practice, directly by more patients being treated with an effective intervention and indirectly through adoption of evidence-based guidelines. It is in this setting of stroke treatment that diagnostic and interventional radiologists have played a crucial role and created clinical impact.

Cholinergic signaling of muscarinic receptors directly involves in the neuroprotection of muscone by inducing Ca2+ antagonism and maintaining mitochondrial function

ETHNOPHARMACOLOGICAL RELEVANCE

Musk, a traditional Chinese medicine, is broadly used in inducing resuscitation and refreshing the mind, activating blood and alleviating pain. It is commonly used for the treatment of ischemic stroke, and muscone is its core medicinal component.

AIM OF THE STUDY

The aim of this study was to explore whether muscone ameliorates neuronal damage through cholinergic signaling of muscarinic receptors.

MATERIALS AND METHODS

The effects of muscone were tested in a rat model of middle cerebral artery occlusion (MCAO) as well as injured neurons induced by oxygen-glucose deprivation (OGD) in PC12 cells. Cell counting kit 8 (CCK8) assay was used to measure the cell viability, and the production of lactate dehydrogenase (LDH) and adenosine-triphosphate (ATP) were examined by kit. 2',7'-Dichlorodihydrofluorescein diacetate (DCFH-DA), tetramethylrhodamine ethyl ester (TMRE) and Fluo-4 acetoxymethyl ester (Fluo-4 AM) staining were used to demonstrate effect of muscone on the reactive oxygen species (ROS) level, mitochondria membrane potential (MMP) and intracellular Ca2+ measurement in cells respectively, in which all of those staining was visualized by laser confocal microscope. For in vivo experiments, rats' cerebral blood flow was measured using laser Doppler blood flowmetry to evaluate the MCAO model, and a modified neurological severity score (mNSS) was used to assess the recovery of neurological function. Calculate infarct rate was measured by 2,3,5-Triphenyl Tetrazolium Chloride (TTC) staining. Except DCFH-DA and Fluo-4 AM staining, 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethyl benzimidazolylcarbocyanine iodide (JC-1) staining was used to observe intracellular Ca2+ measurement in brain cells. Protein levels in cells and tissues were detected by Western blot.

RESULTS

Pretreatment with muscone significantly improved the cell viability, lactic acid production, mitochondrial membrane potential collapse and function, Ca2+ overload, ROS generation, and cell apoptosis in OGD PC12 cells. Muscone also regulated PI3K, ERK and AKT signal pathways by activating cholinergic signaling of muscarinic receptors in PC12 cells induced with OGD. More importantly, the blocking of cholinergic signaling of muscarinic receptors by atropine significantly reduces the neuroprotective effects of muscone, including the cell viability, Ca2+ efflux, and mitochondrial repair. Furthermore, muscone was found to effectively alleviate mitochondrial dysfunction and elevated levels of ROS induced by the MCAO in the brain tissue. Notably, this beneficial effect of muscone was attenuated by atropine but not by (+)-Sparteine.

CONCLUSIONS

Our study indicates that muscone exerts its neuroprotective effects by activating muscarinic receptors of cholinergic signaling, thus providing a promising therapeutic target for the treatment of OGD-induced nerve injury in stroke. The findings suggest that these treatments may hold potential benefits for stroke patients.

Endovascular Thrombectomy With or Without Thrombolysis for Stroke: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background

To this date, whether to administer intravenous thrombolysis (IVT) prior to endovascular thrombectomy (EVT) for stroke patients still stirs some debate. We aimed to systematically update the evidence from randomized trials comparing EVT alone vs EVT with bridging IVT.

Methods

We searched MEDLINE, EMBASE, and the Cochrane Library to identify randomized controlled trials (RCTs) comparing EVT with or without IVT in patients presenting with stroke secondary to a large vessel occlusion. We conducted meta-analyses using random-effects models to compare functional independence, mortality, and symptomatic intracranial hemorrhage (sICH), between EVT and EVT with IVT. We assessed risk of bias using the Cochrane risk-of-bias tool and certainty of evidence for each outcome using the GRADE approach.

Results

Of 11,111 citations, we included 6 studies with a total of 2336 participants. We found low-certainty evidence of possibly a small decrease in the proportion of patients with functional independence (risk difference [RD] -2.0%, 95% CI -5.9% to 2.0%), low-certainty evidence that there is possibly a small increase in mortality (RD 1.0%, 95% CI -2.2% to 4.7%), and moderate-certainty evidence that there is probably a decrease in sICH (RD -1.0%, 95% CI -1.6% to .7%) for patients with EVT alone compared to EVT plus IVT, respectively.

Conclusion

Low-certainty evidence shows that there is possibly a small decrease in functional independence, low-certainty evidence shows that there is possibly a small increase in mortality, and moderate-certainty evidence that there is probably a decrease in sICH for patients with EVT alone compared to EVT plus IVT.

Updated estimates of large and medium vessel strokes, mechanical thrombectomy trends, and future projections indicate a relative flattening of the growth curve but highlight opportunities for expanding endovascular stroke care

BACKGROUND

A study was undertaken to determine the incidence of acute ischemic stroke (AIS) and strokes related to large (LVO) and medium (MVO) vessel occlusions, and to estimate annual mechanical thrombectomy (MT) volume, past trends and future growth.

METHODS

A population-based analysis was performed to estimate the rate of AIS, LVOs (internal carotid artery terminus, M1 branch of the middle cerebral artery, basilar artery) and MVOs (M2 and M3 branches of the middle cerebral artery, anterior and posterior cerebral arteries). MT estimates were determined from multiple governmental data sources. Annual US numbers were adjusted for population growth.

RESULTS

The incidence of AIS is estimated at 216 (95% CI 199 to 238)/100 000 persons/year or 718 191 (95% CI 661 483 to 791 121) AIS/year in the USA. A vascular occlusion was observed in 21% of patients with AIS (95% CI 15 to 29). The rate of LVO was 24/100 000 persons/year (95% CI 19 to 31) or 80 075 (95% CI 62 457 to 104 375) LVOs/year, and the rate of MVO was 20/100 000 persons/year or 65 798 (95% CI 45 555 to 95 110) MVOs/year. MT estimates for 2021 are 39 164 procedures with a flattening of the growth curve from 2019 (9%, 2020-2021; 4%, 2019-2020) as opposed to initial steep growth from 2015 to 2018. Current MT procedures represent 5% of all AIS, 27% of all vascular occlusions (LVO+MVO) and 38% of all LVO and M2 occlusions. The current trajectory indicates a future growth of 5-10%/year for the next several years.

CONCLUSION

A decline in MT growth is observed. The incidence of LVO+MVO is estimated at 44/100 000 persons/year or almost 144 000 large and medium vessel strokes annually. Of these, currently an estimated 27% undergo an MT procedure, indicating an opportunity for growth. Further expansion may require focusing on the elderly, medium vessel strokes and workflow efficiencies from diagnosis to treatment.

Reperfusion therapy for acute ischemic stroke: where are we in 2023?

Over the last three decades, stroke care has undergone significant transformations mainly driven by the introduction of reperfusion therapy and the organization of systems of care. Patients receiving treatment through a well-structured stroke service have a much higher chance of favorable outcomes, thereby decreasing both disability and mortality. In this article, we reviewed the scientific evidence for stroke reperfusion therapy, including thrombolysis and thrombectomy, and its implementation in the public health system in Brazil.

Differential thrombectomy utilization across hospital classifications in the United States

OBJECTIVES

To determine hospital-level factors associated with thrombectomy uptake.

MATERIALS AND METHODS

The Nationwide Emergency Department Sample was retrospectively queried to determine the total number of thrombectomies performed based on different hospital characteristics. Joint point analysis was used to determine which years were associated with significant increases in the number of high-volume thrombectomy centers (ostensibly defined as >50 thrombectomies/year), thrombectomy-capable centers (>15 thrombectomies/year), and total number of thrombectomies performed. Multivariable logistic regression was used to determine hospital factors associated with having an increased odds of performing thrombectomies, and of being classified as a high-volume thrombectomy or a thrombectomy-capable center.

RESULTS

Between 2007-2020 there was a stepwise increase in the number of thrombectomy-capable and high-volume thrombectomy centers in the United States. In 2020, there were a total of 15,705 thrombectomies performed, with 89 high-volume thrombectomy centers, and 359 thrombectomy-capable centers. The number of thrombectomy-capable centers significantly increased after 2011. After 2013 and 2016 there was a significant change in the growth rate of high-volume thrombectomy centers. There was also a significant increase in the total number of thrombectomies performed after 2016. Hospital characteristics that were associated with an increased likelihood of being classified as thrombectomy-capable or high-volume included trauma level 1 and 2 hospitals.

CONCLUSIONS

Between 2007 and 2020, there was a marked growth in thrombectomy utilization for acute ischemic stroke. This growth outpaced new diagnoses of ischemic stroke, and was driven largely by certain hospital types, with the greatest rises following seminal publications of positive randomized thrombectomy trials.

Mechanical Thrombectomy with Intravenous Thrombolysis versus Thrombolysis Alone for the Treatment of Stroke: A Systematic Review of Economic Evaluations

Mechanical thrombectomy has revolutionized the management of stroke by improving the recanalization rates and reducing deleterious consequences. It is now the standard of care despite the high financial cost. A considerable number of studies have evaluated its cost effectiveness. Therefore, this study aimed to identify economic evaluations of mechanical thrombectomy with thrombolysis compared with thrombolysis alone to provide an update of existing evidence, focusing on the period after proof of effectiveness of mechanical thrombectomy. Twenty-one studies were included in the review: 18 were model-based economic evaluations to simulate long-term outcomes and costs, and 19 were conducted in high-income countries. Incremental cost-effectiveness ratios ranged from -$5,670 to $74,216 per quality-adjusted life year. Mechanical thrombectomy is cost-effective in high-income countries and in the populations selected for clinical trials. However, most of the studies used the same data. There is a lack of real-world and long-term data to analyze the cost effectiveness of mechanical thrombectomy in treating the global burden of stroke.

Endovascular Treatment plus Medical Treatment versus Medical Treatment Alone in Ischemic Stroke: A Systematic Review and Meta-Analysis

INTRODUCTION

This study was conducted to assess the hypothesis that endovascular treatment in addition to medical treatment improve stroke mortality and post-stroke disability.

METHODS

In this systematic review and meta-analysis, the studies were included if they were randomized controlled trials in design and compared between endovascular treatment and medical therapy versus medical therapy alone in stroke management.

RESULTS

The search yielded 22 articles that included 5,049 patients. The analysis showed significant association between the intervention and reduction in disability measured by Modified Rankin Scale (mRS) (mRS = 0-2) (odds ratio [OR] = 1.61; 95% confidence intervals [95% CI]: 1.27-2.06) and National Institute of Health Stroke Scale (NIHSS) (NIHSS = 0-15) (OR = 2.13; 95% CI: 1.04-4.34). Also, we found a significant difference in disability scores between the intervention and the medical therapy group (mRS weighted mean difference [WMD] = -0.59; 95% CI: -1.15 to -0.02, NIHSS WMD = -4.52; 95% CI: -6.32 to -2.72). Additionally, there was significant reduction in mortality in the intervention group (OR = 0.79; 95% CI: 0.68-0.92). There was no significant difference in the rate of any serious adverse effects between the two study groups except for asymptomatic intracerebral hemorrhage.

CONCLUSION

Our study provides strong evidence stemmed from randomized clinical trials that endovascular treatment combined with medical therapy is superior to medical therapy alone in the management of stroke.

Effect of race/ethnicity on arterial recanalization following intravenous thrombolysis in acute ischemic stroke patients

INTRODUCTION

Several reports have identified that clinical outcomes such as death or disability in acute ischemic stroke (AIS) patients following intravenous (IV) tissue plasminogen activator (tPA) treatment can vary according to race and ethnicities. We determined the effect of race/ethnicity on rates of arterial recanalization in AIS patients with large vessel occlusion (LVO) after IV tPA.

METHODS

We analyzed 234 patients with LVO detected on computed tomographic angiography (CTA) who received IV tPA and subsequently underwent angiography for potential thrombectomy. The primary occlusion sites on CTA and digital subtracted angiography (DSA) were compared and a score was given to the level of recanalization with values ranging from 1 (complete recanalization), 2 (partial recanalization), or 3 (no recanalization).The effect of race/ethnicity were assessed for predicting vessel recanalization using the covariates of age, gender, time since stroke onset, tPA dose received, NIHSS (National Institute of Health Stroke Scale) score at baseline, and location of the occlusion, using logistic regression analysis.

RESULTS

Five patients (2.1%) were Hispanic or Latino, 8 (3.4%) Asian, 24 (10.3%) African American, and 197 (84.2%) White. A total of 50% had a distal ICA/proximal M1 occlusion, 20% distal M1 occlusion, and 16% single M2 occlusion. At the primary occlusion site, 44 (18.8%) had complete recanalization on post IV tPA angiogram, 17 (7.3%) had partial recanalization, and 165 (70.5%) had no recanalization. We did not find any association between race/ethnicity and vessel recanalization post IV tPA (Nonwhite combined [OR=1.49, p=0.351]; Asian [OR=1.460, p=0.650]; African American [OR=1.508, p=0.415]; White [OR=0.672, p=0.351]; ethnicity (Hispanic or Latino) [OR= 1.008, p=0.374]); Occlusion location (OR=0.189, p<0.001). Final TICI scores and mRS at 90 days were similar among the different groups.

CONCLUSION

Approximately 19% of patients had complete recanalization after IV tPA, but race and ethnicity did not seem to have an effect on arterial recanalization. Arterial recanalization was only affected by location of occlusion.

Thrombectomy vs. medical management for large vessel occlusion strokes with minimal symptoms

Patients with acute ischemic stroke (AIS) presenting mild symptoms with a low National Institutes of Health Stroke Scale (NIHSS) score ≤8 and also found to have an intracranial large vessel occlusion (LVO) undergo endovascular thrombolysis (ET) or medical management alone. The current study aimed to evaluate the safety and effectiveness of medical management vs. ET therapy among patients with mild AIS symptoms (NIHSS score ≤8) accompanied by LVO. The present meta-analysis included articles involving mild AIS, LVO, thrombectomy/ET and medical management alone published in full-text form (from 1980 to 2022). Collected variables included: First author name, covered study period, publication year, the total number of patients and age, number of males, presence of diabetes mellitus, hypertension, atrial fibrillation, prior ischemic stroke, location, NIHSS of admission, modified Rankin scale, bleeding, morbidity and mortality. After the initial search and applying all exclusion and inclusion criteria, eight articles were left in the final article pool. The total number of patients who underwent ET was 569, compared with 1097 with medical management for LVO strokes with minimal symptoms. The findings of the present meta-analysis study point out that ET management may be associated with a high risk of bleeding and mortality in patients with LVO presenting with mild symptoms (NIHSS score ≤8).

Mechanical thrombectomy with intra-arterial alteplase provided better functional outcomes for AIS-LVO: a meta-analysis

Background

Several clinical trials have shown that intra-arterial thrombolysis using alteplase during mechanical thrombectomy (MT) has a better outcome than MT alone in ischemic stroke management. We performed the current meta-analysis to estimate the efficacy and safety of MT with intra-arterial alteplase therapy.

Methods

The MEDLINE, Embase, Cochrane Library, and ClinicalTrials.gov databases were searched up to Mar. 2022 to identify the clinical trials that compared MT alone versus MT with intra-arterial alteplase therapy. STATA 16.0 was used for statistical analysis. The odds ratios (ORs) and 95% confidence intervals (95%CIs) were calculated with a random effect model.

Results

Seven studies involving 1,083 participants were included. The primary outcomes were better functional outcomes, defined as a modified Rankin Scale (mRS) score between 0 and 2 at 90  days, and successful recanalization, defined as a modified thrombolysis in cerebral infarction (mTICI) score  ≥  2b. Compared to MT alone, MT with intra-arterial alteplase did not lead to higher mTICI scores (OR 1.58, 95%CI 0.94 to 2.67, p = 0.085, I2 = 16.8%) but did lead to better mRS (OR 1.37, 95%CI 1.01 to 1.86, p = 0.044). There was no increase in mortality or bleeding events in the overall or subgroup analyses.

Conclusion

MT with intra-arterial alteplase did not improve the recanalization rate but provided better functional outcomes. The intervention did not increase adverse effects in any subgroup at the same time.

Clinical trial registration

http://inplasy.com, identifier INPLASY202240027.

Recent Vitamin K Antagonist Use and Intracranial Hemorrhage After Endovascular Thrombectomy for Acute Ischemic Stroke

Importance

Use of oral vitamin K antagonists (VKAs) may place patients undergoing endovascular thrombectomy (EVT) for acute ischemic stroke caused by large vessel occlusion at increased risk of complications.

Objective

To determine the association between recent use of a VKA and outcomes among patients selected to undergo EVT in clinical practice.

Design, Setting, and Participants

Retrospective, observational cohort study based on the American Heart Association's Get With the Guidelines-Stroke Program between October 2015 and March 2020. From 594 participating hospitals in the US, 32 715 patients with acute ischemic stroke selected to undergo EVT within 6 hours of time last known to be well were included.

Exposure

VKA use within the 7 days prior to hospital arrival.

Main Outcome and Measures

The primary end point was symptomatic intracranial hemorrhage (sICH). Secondary end points included life-threatening systemic hemorrhage, another serious complication, any complications of reperfusion therapy, in-hospital mortality, and in-hospital mortality or discharge to hospice.

Results

Of 32 715 patients (median age, 72 years; 50.7% female), 3087 (9.4%) had used a VKA (median international normalized ratio [INR], 1.5 [IQR, 1.2-1.9]) and 29 628 had not used a VKA prior to hospital presentation. Overall, prior VKA use was not significantly associated with an increased risk of sICH (211/3087 patients [6.8%] taking a VKA compared with 1904/29 628 patients [6.4%] not taking a VKA; adjusted odds ratio [OR], 1.12 [95% CI, 0.94-1.35]; adjusted risk difference, 0.69% [95% CI, -0.39% to 1.77%]). Among 830 patients taking a VKA with an INR greater than 1.7, sICH risk was significantly higher than in those not taking a VKA (8.3% vs 6.4%; adjusted OR, 1.88 [95% CI, 1.33-2.65]; adjusted risk difference, 4.03% [95% CI, 1.53%-6.53%]), while those with an INR of 1.7 or lower (n = 1585) had no significant difference in the risk of sICH (6.7% vs 6.4%; adjusted OR, 1.24 [95% CI, 0.87-1.76]; adjusted risk difference, 1.13% [95% CI, -0.79% to 3.04%]). Of 5 prespecified secondary end points, none showed a significant difference across VKA-exposed vs VKA-unexposed groups.

Conclusions and Relevance

Among patients with acute ischemic stroke selected to receive EVT, VKA use within the preceding 7 days was not associated with a significantly increased risk of sICH overall. However, recent VKA use with a presenting INR greater than 1.7 was associated with a significantly increased risk of sICH compared with no use of anticoagulants.

Endovascular thrombectomy with or without thrombolysis bridging in patients with acute ischaemic stroke: protocol for a systematic review, meta-analysis of randomised trials and cost-effectiveness analysis

INTRODUCTION

Current published guidelines and meta-analyses comparing endovascular thrombectomy (EVT) alone versus EVT with bridging intravenous thrombolysis (IVT) suggest that EVT alone is non-inferior to EVT with bridging thrombolysis in achieving favourable functional outcome. Because of this controversy, we aimed to systematically update the evidence and meta-analyse data from randomised trials comparing EVT alone versus EVT with bridging thrombolysis, and performed an economic evaluation comparing both strategies.

METHODS AND ANALYSIS

We will conduct a systematic review of randomised controlled trials comparing EVT with or without bridging thrombolysis in patients presenting with large vessel occlusions. We will identify eligible studies by systematically searching the following databases from inception without any language restrictions: MEDLINE (through Ovid), Embase and the Cochrane Library. The following criteria will be used to assess eligibility for inclusion: (1) adult patients ≥18 years old; (2) randomised patients to EVT alone or to EVT with IVT; and (3) measured outcomes, including functional outcomes, at least 90 days after randomisation. Pairs of reviewers will independently screen the identified articles, extract information and assess the risk of bias of eligible studies. We will use the Cochrane Risk-of-Bias tool to evaluate risk of bias. We will also use the Grading of Recommendations, Assessment, Development and Evaluation approach to assess the certainty in evidence for each outcome. We will then perform an economic evaluation based on the extracted data.

ETHICS AND DISSEMINATION

This systematic review will not require a research ethics approval because no confidential patient data will be used. We will disseminate our findings by publishing the results in a peer-reviewed journal and via presentation at conferences.

PROSPERO REGISTRATION NUMBER

CRD42022315608.

Endovascular Thrombectomy for Anterior Circulation Large Vessel Occlusion Stroke: An Evolution of Trials

The last decade's progress in demonstrating the clinical benefit of endovascular thrombectomy (EVT) in patients with large vessel occlusion stroke has transformed the paradigm of care for these patients. This review presents the milestones in implementing EVT as standard of care, demonstrates the current state of evidence, provides guidance for identifying the candidate patient for EVT, and highlights unsolved and controversial issues. Ongoing trials investigate broadening of EVT indications for patients who present with large core infarction, adjunctive intra-arterial thrombolysis, medium vessel occlusion, low NIHSS, and tandem occlusion.

Femoral Access-Site Complications with Tenecteplase versus Alteplase before Mechanical Thrombectomy for Large-Vessel-Occlusion Stroke

BACKGROUND AND PURPOSE

IV thrombolysis with alteplase before mechanical thrombectomy for emergent large-vessel-occlusion stroke is associated with access-site bleeding complications. However, the incidence of femoral access-site complications with tenecteplase before mechanical thrombectomy requires exploration. Here, femoral access-site complications with tenecteplase versus alteplase before mechanical thrombectomy for large-vessel-occlusion stroke were compared.

MATERIALS AND METHODS

All patients receiving IV thrombolytics before mechanical thrombectomy for large-vessel-occlusion stroke who presented from January 2020 to August 2022 were reviewed. In May 2021, our health care system switched from alteplase to tenecteplase as the primary thrombolytic for all patients with stroke, facilitating the comparison of alteplase-versus-tenecteplase femoral access-site complication rates. Major (requiring surgery) and minor (managed conservatively) access-site complications were assessed.

RESULTS

One hundred thirty-nine patients underwent transfemoral mechanical thrombectomy for large-vessel-occlusion stroke, of whom 46/139 (33.1%) received tenecteplase and 93/139 (66.9%) received alteplase. In all cases (n = 139), an 8F sheath was inserted without sonographic guidance, and vascular closure was obtained with an Angio-Seal. Baseline demographics, concomitant antithrombotic medications, and periprocedural coagulation lab findings were similar between groups. The incidence of conservatively managed groin hematomas (2.2% versus 4.3%), delayed access-site oozing requiring manual compression (6.5% versus 2.2%), and arterial occlusion requiring surgery (2.2% versus 1.1%) was similar between the tenecteplase and alteplase groups, respectively (P = not significant). No dissection, arteriovenous fistula, or retroperitoneal hematoma was observed.

CONCLUSIONS

Tenecteplase compared with alteplase before mechanical thrombectomy for large-vessel-occlusion stroke is not associated with an alteration in femoral access-site complication rates.

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.

Adapting to Evolving Technologies and Treatment Guidelines in a Procedural Trial: A Qualitative Review of the CREST-2 Experience

Multiple challenges confront procedural trials, including slow enrollment, lack of equipoise among patients and physicians, and failure to achieve adequate masking. Nonetheless, randomized clinical trials provide the best evidence of efficacy. The evolution of technology, techniques, and standards of care during the conduct of procedural trials challenges external validity. In this study, we review how a multicenter trial of revascularization of asymptomatic carotid arteries for stroke prevention has managed changes in treating carotid stenosis and medical management of atherothrombotic disease. TRIAL REGISTRATION INFORMATION: ClinicalTrials.gov number: NCT02089217.

Different types of percutaneous endovascular interventions for acute ischemic stroke

BACKGROUND

Acute ischemic stroke (AIS) is the abrupt reduction of blood flow to a certain area of the brain which causes neurologic dysfunction. Different types of percutaneous arterial endovascular interventions have been developed, but as yet there is no consensus on the optimal therapy for people with AIS.

OBJECTIVES

To compare the safety and efficacy of different types of percutaneous arterial endovascular interventions for treating people with AIS.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; Issue 4 of 12, 2022), MEDLINE Ovid (1946 to 13 May 2022), Embase (1947 to 15 May 2022), Science Citation Index Web of Science (1900 to 15 May 2022), Scopus (1960 to 15 May 2022), and China Biological Medicine Database (CBM; 1978 to 16 May 2022). We also searched the ClinicalTrials.gov trials register and the World Health Organization (WHO) International Clinical Trials Registry Platform to 16 May 2022.

SELECTION CRITERIA

Randomized controlled trials (RCTs) comparing one percutaneous arterial endovascular intervention with another in treating adult patients who have a clinical diagnosis of AIS due to large vessel occlusion and confirmed by imaging evidence, including thrombo-aspiration, stent-retrieval thrombectomy, aspiration-retriever combined technique, and thrombus mechanical fragmentation.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed the literature searches, identified eligible trials, and extracted data. A third review author participated in discussions to reach consensus decisions when any disputes occurred. We assessed risk of bias and applied the GRADE approach to evaluate the quality of the evidence. The primary outcome was rate of modified Rankin Scale (mRS) of 0 to 2 at three months. Secondary outcomes included the rate of modified Thrombolysis In Cerebral Infarction (mTICI) of 2b to 3 postprocedure, all-cause mortality within three months, rate of intracranial hemorrhage on imaging at 24 hours, rate of symptomatic intracranial hemorrhage at 24 hours, and rate of procedure-related adverse events within three months.

MAIN RESULTS

Four RCTs were eligible. The current meta-analysis included two trials with 651 participants comparing thrombo-aspiration with stent-retrieval thrombectomy. We judged the quality of evidence to be high in both trials according to Cochrane's risk of bias tool RoB 2. There were no significant differences between thrombo-aspiration and stent-retrieval thrombectomy in rate of mRS of 0 to 2 at three months (risk ratio [RR] 0.97, 95% confidence interval [CI] 0.82 to 1.13; P = 0.68; 633 participants; 2 RCTs); rate of mTICI of 2b to 3 postprocedure (RR 1.01, 95% CI 0.95 to 1.07; P = 0.77; 650 participants; 2 RCTs); all-cause mortality within three months (RR 1.01, 95% CI 0.74 to 1.37; P = 0.95; 633 participants; 2 RCTs); rate of intracranial hemorrhage on imaging at 24 hours (RR 1.03, 95% CI 0.86 to 1.24; P = 0.73; 645 participants; 2 RCTs); rate of symptomatic intracranial hemorrhage at 24 hours (RR 0.90, 95% CI 0.49 to 1.68; P = 0.75; 645 participants; 2 RCTs); and rate of procedure-related adverse events within three months (RR 0.98, 95% CI 0.68 to 1.41; P = 0.90; 651 participants; 2 RCTs). Another two included studies reported no differences for the comparisons of combined therapy versus stent-retrieval thrombectomy or thrombo-aspiration. One RCT is ongoing.

AUTHORS' CONCLUSIONS

This review did not establish any difference in safety and effectiveness between the thrombo-aspiration approach and stent-retrieval thrombectomy for treating people with AIS. Furthermore, the combined group did not show any obvious advantage over either intervention applied alone.

[Intravenous thrombolysis of ischemic stroke-Current status]

Intravenous thrombolysis (IVT) treatment with alteplase (rtPA) is an essential part of the routine treatment of patients with ischemic stroke since its introduction in the late 1990s. Rapid treatment is of essential importance. For patients with an unclear time window, various mismatch concepts have been established to identify salvageable brain tissue prior to IVT. Numerous official contraindications for rtPA are not evidence-based; for example, current data from observational studies show that systemic thrombolytic treatment is possible even in patients receiving direct oral anticoagulant (DOAC) treatment. Tenecteplase (TNK) is an alternative thrombolytic agent with some pharmacologic advantages. The most recent guidelines indicate that TNK is particularly advantageous over rtPA in patients treated in combination with endovascular stroke therapy (EST). The combination of IVT and EST should primarily be performed in the 4.5‑h time window in patients without contraindications; in the later time window EST alone is conceivable if it can be performed without delay.

Mechanism of action and therapeutic potential of dimethyl fumarate in ischemic stroke

Dimethyl fumarate (DMF) is an immunomodulatory drug currently approved for the treatment of multiple sclerosis and psoriasis. Its benefits on ischemic stroke outcomes have recently come to attention. To date, only tissue plasminogen activators (tPAs) and clot retrieval methods have been approved by the FDA for the treatment of ischemic stroke. Ischemic conditions lead to inflammation through diverse mechanisms, and recanalization can worsen the state. DMF and the nuclear factor erythroid-derived 2-related factor 2 (Nrf2) pathway it regulates seem to be important in postischemic inflammation, and animal studies have demonstrated that the drug improves overall stroke outcomes. Although the exact mechanism is still unknown, studies indicate that these beneficial impacts are due to the modulation of immune responses, blood-brain barrier permeability, and hemodynamic adjustments. One major component evaluated before, during, and after tPA therapy in stroke patients is blood pressure (BP). Recent studies have found that DMF may impact BP. Both hypotension and hypertension need correction before treatment, which may delay the appropriate intervention. Since BP management is crucial in managing stroke patients, it is important to consider DMF's role in this matter. That being said, it seems further investigations on DMF may lead to an alternative approach for stroke patients. In this article, we discuss the mechanistic roles of DMF and its potential role in stroke based on previously published literature and laboratory findings.

Evaluation of Collateral Circulation in Patients with Acute Ischemic Stroke

The cerebral collateral circulation is an increasingly important consideration in the management of acute ischemic stroke and is a key determinant of outcomes. Growing evidence has demonstrated that better collaterals can predict the rate of infarct progression, degree of recanalization, the likelihood of hemorrhagic transformation and various therapeutic opportunities. Collaterals can also identify those unlikely to respond to reperfusion therapies, helping to optimize resources. More randomized trials are needed to evaluate the risks and benefits of endovascular reperfusion with consideration of collateral status. This reviews our current understanding of the pathophysiologic mechanisms, effect on outcomes and strategies for improvement of the collateral system.

Big Data in Stroke: How to Use Big Data to Make the Next Management Decision

The last decade has seen significant advances in the accumulation of medical data, the computational techniques to analyze that data, and corresponding improvements in management. Interventions such as thrombolytics and mechanical thrombectomy improve patient outcomes after stroke in selected patients; however, significant gaps remain in our ability to select patients, predict complications, and understand outcomes. Big data and the computational methods needed to analyze it can address these gaps. For example, automated analysis of neuroimaging to estimate the volume of brain tissue that is ischemic and salvageable can help triage patients for acute interventions. Data-intensive computational techniques can perform complex risk calculations that are too cumbersome to be completed by humans, resulting in more accurate and timely prediction of which patients require increased vigilance for adverse events such as treatment complications. To handle the accumulation of complex medical data, a variety of advanced computational techniques referred to as machine learning and artificial intelligence now routinely complement traditional statistical inference. In this narrative review, we explore data-intensive techniques in stroke research, how it has informed the management of stroke patients, and how current work could shape clinical practice in the future.

Mechanical Thrombectomy for Acute Ischemic Stroke

OBJECTIVE

Endovascular stroke therapy has greatly improved the ability to treat the deadliest and most disabling form of acute ischemic stroke. This article summarizes some of the recent innovations in this field and discusses likely future developments.

LATEST DEVELOPMENTS

At present, there is robust activity to improve all facets of care for patients with large vessel occlusion stroke, including better prehospital routing, more efficient in-hospital screening, expanding indications for thrombectomy eligibility, innovating novel thrombectomy devices, and improving the effects of recanalization on clinical outcomes. In addition, the integration of endovascular stroke therapy (EVT)-an emergent and frequently off-hours procedure that requires a specialized team of nurses, technologists, and physicians-into acute stroke care has transformed referral patterns, hospital accreditation pathways, and physician practices. The eligibility for the procedure will potentially continue to grow to include patients screened without advanced imaging, larger core infarcts, and more distal occlusions.

ESSENTIAL POINTS

In this review, we discuss the current state of EVT and its implications for practice, and present three cases that highlight some of the directions in which the field is moving.

Impact of Time to Treatment on Endovascular Thrombectomy Outcomes in the Early Versus Late Treatment Time Windows

BACKGROUND

The impact of time to treatment on outcomes of endovascular thrombectomy (EVT) especially in patients presenting after 6 hours from symptom onset is not well characterized. We studied the differences in characteristics and treatment timelines of EVT-treated patients participating in the Florida Stroke Registry and aimed to characterize the extent to which time impacts EVT outcomes in the early and late time windows.

METHODS

Prospectively collected data from Get With the Guidelines-Stroke hospitals participating in the Florida Stroke Registry from January 2010 to April 2020 were reviewed. Participants were EVT patients with onset-to-puncture time (OTP) of ≤24 hours and categorized into early window treated (OTP ≤6 hours) and late window treated (OTP >6 and ≤24 hours). Association between OTP and favorable discharge outcomes (independent ambulation, discharge home and to acute rehabilitation facility) as well as symptomatic intracerebral hemorrhage and in-hospital mortality were examined using multilevel-multivariable analysis with generalized estimating equations.

RESULTS

Among 8002 EVT patients (50.9% women; median age [±SD], 71.5 [±14.5] years; 61.7% White, 17.5% Black, and 21% Hispanic), 34.2% were treated in the late time window. Among all EVT patients, 32.4% were discharged home, 23.5% to rehabilitation facility, 33.7% ambulated independently at discharge, 5.1% had symptomatic intracerebral hemorrhage, and 9.2% died. As compared with the early window, treatment in the late window was associated with lower odds of independent ambulation (odds ratio [OR], 0.78 [0.67-0.90]) and discharge home (OR, 0.71 [0.63-0.80]). For every 60-minute increase in OTP, the odds of independent ambulation reduced by 8% (OR, 0.92 [0.87-0.97]; P<0.001) and 1% (OR, 0.99 [0.97-1.02]; P=0.5) and the odds of discharged home reduced by 10% (OR, 0.90 [0.87-0.93]; P<0.001) and 2% (OR, 0.98 [0.97-1.00]; P=0.11) in the early and late windows, respectively.

CONCLUSIONS

In routine practice, just over one-third of EVT-treated patients independently ambulate at discharge and only half are discharged to home/rehabilitation facility. Increased time from symptom onset to treatment is significantly associated with lower chance of independent ambulation and ability to be discharged home after EVT in the early time window.

Collaterals and Elusive Ischemic Penumbra

As alternative blood supply routes, collateral blood vessels can play a crucial role in determining patient outcomes in acute and chronic intracranial occlusive diseases. Studies have shown that increased collateral circulation can improve functional outcomes and reduce mortality, particularly in those who are not eligible for reperfusion therapy. This article aims to discuss the anatomy and physiology of collateral circulation, describe current imaging tools used to measure collateral circulation, and identify the factors that influence collateral status.

Collateral Status and Outcomes after Thrombectomy

Endovascular treatment (EVT) using novel mechanical thrombectomy devices has been the gold standard for patients with acute ischemic stroke caused by large vessel occlusion. Selection criteria of randomized control trials commonly include baseline infarct volume with or without penumbra evaluation. Although the collateral status has been studied and is known to modify imaging results and clinical course, it has not been commonly used for trials. Many post hoc studies, however, revealed that collateral status can help predict infarct growth, recanalization success, decreased hemorrhagic transformation after EVT, and extension of the therapeutic time window for revascularization. Here, we systematically review the recent literature and summarized the outcomes of EVT according to the collateral status of patients with acute ischemic stroke caused by large vessel occlusion. The studies reviewed indicate that pretreatment collateral circulation is associated with both clinical and imaging outcomes after EVT in patients with acute ischemic stroke due to large vessel occlusion although most patients were already selected by other imaging or clinical criteria. However, treatment decisions using information on patients' collateral status have not progressed in clinical practice. Further randomized trials are needed to evaluate the risks and benefits of EVT in consideration of collateral status.

Sex differences in the utilization and outcomes of endovascular treatment after acute ischemic stroke: A systematic review and meta-analysis

Background

Studies of sex differences in the use and outcomes of endovascular treatment (EVT) for acute ischemic stroke report inconsistent results.

Methods

We systematically searched PubMed and Embase databases for studies examining sex-specific utilization of EVT for acute ischemic stroke published before 31 December 2021. Estimates were compared by study type: randomized clinical trials (RCTs) and non-RCTs (hospital-based, registry-based or administrative data). Random effects odds ratios (ORs) were generated to quantify sex differences in EVT use. To estimate sex differences in functional outcome on the modified Rankin scale after EVT, the female:male ratio of ORs and 95% confidence intervals (CIs) were obtained from ordinal or binary analysis.

Results

6,396 studies were identified through database searching, of which 594 qualified for a full review. A total of 51 studies (36 non-RCT and 15 RCTs) reporting on sex-specific utilization of EVT were included, and of those 10 estimated the sex differences of EVT on functional outcomes. EVT use was similar in women and men both in non-RCTs (OR: 1.03, 95% CI: 0.96-1.11) and RCTs (1.02, 95% CI: 0.89-1.16), with consistent results across years of publication and regions of study, except that in Europe EVT treatment was higher in women than men (1.15, 95% CI: 1.13-1.16). No sex differences were found in the functional outcome by either ordinal and binary analyses (ORs 0.95, 95% CI: 0.68-1.32] and 0.90, 95% CI: 0.65-1.25, respectively).

Conclusions

No sex differences in EVT utilization or on functional outcomes were evident after acute ischemic stroke from large-vessel occlusion. Further research may be required to examine sex differences in long-term outcomes, social domains, and quality of life.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=226100, identifier: CRD42021226100.

Is Thrombocytopenia an In-Hospital Mortality Risk Factor among Patients with Acute Ischemic Stroke? A Propensity Score-Matched Analysis from the MIMIC-IV Database

(1) Background: We aimed to evaluate the aspect of thrombocytopenia in patients with acute ischemic stroke (AIS); (2) Methods: Patients with AIS were recruited in the Medical Information Mart for Intensive Care IV database from 2008 to 2019. The thrombocytopenia was defined as a platelet blood count of less than 150 K/µL. We compared the patient characteristics and clinical outcomes using propensity score matching (PSM); (3) Results: Thrombocytopenia affected 151 out of the 1236 patients (12.2%). Patients with thrombocytopenia were older (70.5 ± 12.8 vs. 68.4 ± 14.4; SMD = 0.154) and had a higher Charlson comorbidity index (7.3 ± 2.5 vs. 6.7 ± 2.7; SMD = 0.228) and acute physiology score III (44.8 ± 21.0 vs. 38.2 ± 19.1; SMD = 0.328) than those without thrombocytopenia. The risk of in-hospital mortality did not increase linearly or nonlinearly with a lower platelet count (overall p value = 0.794; nonlinear p value = 0.646). After PSM, 147 pairs remained. Thrombocytopenia was not linked with in-hospital mortality (HR: 1.06, 95% CIs: 0.60-1.88); (4) Conclusions: We described the clinical characteristics of patients admitted for thrombocytopenia and AIS who did not receive reperfusion therapy; additionally, we found that thrombocytopenia was not an independent short-term risk factor of in-hospital mortality.

Direct Mechanical Thrombectomy Versus Prior Bridging Intravenous Thrombolysis in Acute Ischemic Stroke: A Systematic Review and Meta-Analysis

BACKGROUND

The current guideline recommends using an intravenous tissue-type plasminogen activator (IV tPA) prior to mechanical thrombectomy (MT) in eligible acute ischemic stroke (AIS) with emergent large vessel occlusion (ELVO). Some recent studies found no significant differences in the long-term functional outcomes between bridging therapy (BT, i.e., IV tPA prior to MT) and direct MT (dMT).

METHODS

We conducted a systematic review and meta-analysis to compare the safety and functional outcomes between BT and dMT in AIS patients with ELVO who were eligible for IV tPA administration. Based on the ELVO location, patients were categorized as the anterior group (occlusion of the anterior circulation), or the combined group (occlusion of the anterior and/or posterior circulation). A subgroup analysis was performed based on the study type, i.e., RCT and non-RCT.

RESULTS

Thirteen studies (3985 patients) matched the eligibility criteria. Comparing the BT and dMT groups, no significant differences in terms of mortality and good functional outcome were observed at 90 days. Symptomatic intracranial hemorrhagic (sICH) events were more frequent in BT patients in the combined group (OR = 0.73, p = 0.02); this result remained significant only in the non-RCT subgroup (OR = 0.67, p = 0.03). The RCT subgroup had a significantly higher rate of successful revascularization in BT patients (OR = 0.73, p = 0.02).

CONCLUSIONS

Our meta-analysis uncovered no significant differences in functional outcome and mortality rate at 90 days between dMT and BT in patients with AIS who had ELVO. Although BT performed better in terms of successful recanalization rate, there is a risk of increased sICH rate in this group.

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.

Collateral Circulation- Evolving from Time Window to Tissue Window

Cerebral collateral circulation refers to the auxiliary vascular structures which compensate cerebral blood flow when it has been compromised due to stenosis or occlusion of the principal supplying arteries. They play a vital role in sustaining blood flow to the ischemic areas in acute, subacute or chronic phases of ischemic stroke or TIA. Good collateral circulation has shown protective effects towards a favorable functional outcome and a lower risk of recurrence of stroke. The benchmark mechanical thrombectomy trials utilized these collateral scoring methods to guide patient selection and prognosticate favorable outcome models. This shows a promising future of the collateral circulation for extending the time frame of the reperfusion therapies by optimally guiding patient selection and moving from a "time window" to a "tissue window."

Endovascular versus Medical Management of Acute Basilar Artery Occlusion: A Systematic Review and Meta-Analysis of the Randomized Controlled Trials

BACKGROUND AND PURPOSE

The optimal management of patients with acute basilar artery occlusion (BAO) is uncertain. We aimed to evaluate the safety and efficacy of endovascular thrombectomy (EVT) compared to medical management (MM) for acute BAO through a meta-analysis of randomized controlled trials (RCTs).

METHODS

We performed a systematic review and meta-analysis of RCTs of patients with acute BAO. We analyzed the pooled effect of EVT compared to MM on the primary outcome (modified Rankin Scale [mRS] of 0-3 at 3 months), secondary outcome (mRS 0-2 at 3 months), symptomatic intracranial hemorrhage (sICH), and 3-month mortality rates. For each study, effect sizes were computed as odds ratios (ORs) with random effects and Mantel-Haenszel weighting.

RESULTS

Four RCTs met inclusion criteria including 988 patients. There were higher odds of mRS of 0-3 at 90 days in the EVT versus MM group (45.1% vs. 29.1%, OR 1.99, 95% confidence interval [CI] 1.04-3.80; P=0.04). Patients receiving EVT had a higher sICH compared to MM (5.4% vs. 0.8%, OR 7.89, 95% CI 4.10-15.19; P<0.01). Mortality was lower in the EVT group (35.5% vs. 45.1%, OR 0.64, 95% CI 0.42-0.99; P=0.05). In an analysis of two trials with BAO patients and National Institutes of Health Stroke Scale (NIHSS) <10, there was no difference in 90-day outcomes between EVT versus MM.

CONCLUSION

In this systematic review and meta-analysis, EVT was associated with favorable outcome and decreased mortality in patients with BAO up to 24 hours from stroke symptoms compared to MM. The treatment effect in BAO patients with NIHSS <10 was less certain. Further studies are of interest to evaluate the efficacy of EVT in basilar occlusion patients with milder symptoms.

[Acute cerebrovascular events-fundamentals]

Acute ischemic stroke and subarachnoid hemorrhage due to a ruptured intracranial aneurysm are cerebrovascular emergencies, in which interventional neuroradiological therapeutic procedures play a crucial role. Profound knowledge about indication based on current guidelines and treatment approaches with their advantages and disadvantages are the basis of an evidence-based therapeutic decision. This article aims to provide an empirical overview for everyday practical situations.

Neuroimaging of Acute Ischemic Stroke: Multimodal Imaging Approach for Acute Endovascular Therapy

Advances in acute ischemic stroke (AIS) treatment have been contingent on innovations in neuroimaging. Neuroimaging plays a pivotal role in the diagnosis and prognosis of ischemic stroke and large vessel occlusion, enabling triage decisions in the emergent care of the stroke patient. Current imaging protocols for acute stroke are dependent on the available resources and clinicians' preferences and experiences. In addition, differential application of neuroimaging in medical decision-making, and the rapidly growing evidence to support varying paradigms have outpaced guideline-based recommendations for selecting patients to receive intravenous or endovascular treatment. In this review, we aimed to discuss the various imaging modalities and approaches used in the diagnosis and treatment of AIS.

Immunologic Implications for Stroke Recovery: Unveiling the Role of the Immune System in Pathogenesis, Neurorepair, and Rehabilitation

Stroke is a debilitating neurologic condition characterized by an interruption or complete blockage of blood flow to certain areas of the brain. While the primary injury occurs at the time of the initial ischemic event or hemorrhage, secondary injury mechanisms contribute to neuroinflammation, disruption of the blood-brain barrier (BBB), excitotoxicity, and cerebral edema in the days and hours after stroke. Of these secondary mechanisms of injury, significant dysregulation of various immune populations within the body plays a crucial role in exacerbating brain damage after stroke. Pathological activity of glial cells, infiltrating leukocytes, and the adaptive immune system promote neuroinflammation, BBB damage, and neuronal death. Chronic immune activation can additionally encourage the development of neurologic deficits, immunosuppression, and dysregulation of the gut microbiome. As such, immunotherapy has emerged as a promising strategy for the clinical management of stroke in a highly patient-specific manner. These strategies include regulatory T cells (Tregs), cell adhesion molecules, cytokines, and monoclonal antibodies. However, the use of immunotherapy for stroke remains largely in the early stages, highlighting the need for continued research efforts before widespread clinical use.

Pharmacological Strategies for Stroke Intervention: Assessment of Pathophysiological Relevance and Clinical Trials

OBJECTIVES

The present review describes stroke pathophysiology in brief and discusses the spectrum of available treatments with different promising interventions that are in clinical settings or are in clinical trials.

METHODS

Relevant articles were searched using Google Scholar, Cochrane Library, and PubMed. Keywords for the search included ischemic stroke, mechanisms, stroke interventions, clinical trials, and stem cell therapy.

RESULTS AND CONCLUSION

Stroke accounts to a high burden of mortality and morbidity around the globe. Time is an important factor in treating stroke. Treatment options are limited; however, agents with considerable efficacy and tolerability are being continuously explored. With the advances in stroke interventions, new therapies are being formulated with a hope that these may aid the ongoing protective and reparative processes. Such therapies may have an extended therapeutic time window in hours, days, weeks, or longer and may have the advantage to be accessible by a majority of the patients.

Developing and predicting of early mortality after endovascular thrombectomy in patients with acute ischemic stroke

Background

Stroke is one of the leading causes of mortality across the world. However, there is a paucity of information regarding mortality rates and associated risk factors in patients with acute ischemic stroke (AIS) undergoing endovascular thrombectomy (EVT). In this study, we aimed to clarify these issues and analyzed previous publications related to mortality in patients treated with EVT.

Methods

We analyzed the survival of 245 consecutive patients treated with mechanical thrombectomy for AIS for which mortality information was obtained. Early mortality was defined as death occurring during hospitalization after EVT or within 7 days following hospital discharge from the stroke event.

Results

Early mortality occurred in 22.8% of cases in this cohort. Recanalization status (modified thrombolysis in cerebral infarction, mTICI) (p = 0.002), National Institute of Health Stroke Scale Score (NIHSS) score 24-h after EVT (p < 0.001) and symptomatic intracerebral hemorrhage (sICH) (p < 0.001) were independently associated with early mortality. Age, sex, cardiovascular risk factors, NIHSS score pre-treatment, Alberta Stroke Program Early CT Score (ASPECTS), stroke subtype, site of arterial occlusion and timing form onset to recanalization did not have an independent influence on survival. Non-survivors had a shorter hospitalization (p < 0.001) but higher costs related to their hospitalization and outpatient care.

Conclusion

The recanalization status, NIHSS score 24-h after EVT and sICH were predictors of early mortality in AIS patients treated with EVT.