Endovascular treatment for acute ischemic stroke

The Role of the Vascular Neurologist in Optimizing Stroke Care

The article summarizes the training pathways and vocational opportunities within the field of vascular neurology. It highlights the groundbreaking clinical trials that transformed acute stroke care and the resultant increased demand for readily available vascular neurology expertise. The article emphasizes the need to train a larger number of diverse physicians in the subspecialty and the role of vascular neurologists in improving outcomes across demographic and geographic lines.

Changes in inpatient brain arteriovenous malformation management in the United States following the ARUBA trial: analysis of an interrupted time series design

The November 2013 online publication of ARUBA, the first multi-institutional randomized controlled trial for unruptured brain arteriovenous malformations (AVMs), has sparked over 100 publications in protracted debates METHODS: This study sought to examine inpatient management patterns of brain AVMs from 2009 to 2016 and observe if changes in U.S. inpatient management were attributable to the ARUBA publication using interrupted time series of brain AVM studies from the National Inpatient Sample data 2009-2016. Outcomes of interest were use of embolization, surgery, combined embolization and microsurgery, radiotherapy, and observation during that admission. An interrupted time series design compared management trends before and after ARUBA. Segmented linear regression analysis tested for immediate and long-term impacts of ARUBA on management. RESULTS: Elective and asymptomatic patient admissions declined 2009-2016. In keeping with the ARUBA findings, observation for unruptured brain AVMs increased and microsurgery decreased. However, embolization, radiosurgery, and combined embolization and microsurgery also increased. For ruptured brain AVMs, treatment modality trends remained positive with even greater rates of observation, embolization, and combined embolization and microsurgery occurring after ARUBA (data on radiosurgery were scarce). None of the estimates for the change in trends were statistically significant. CONCLUSIONS: The publication of ARUBA was associated with a decrease in microsurgery and increase in observation for unruptured brain AVMs in the US. However, inpatient radiotherapy, embolization, and combined embolization and surgery also increased, suggesting trends moved counter to ARUBA's conclusions. This analysis suggested that ARUBA had a small impact as clinicians rejected ARUBA's findings in managing unruptured brain AVMs.

Current State of Evidence for Neuroimaging Paradigms in Management of Acute Ischemic Stroke

Stroke is the chief differential diagnosis in patient presenting to the emergency room with abrupt onset focal neurological deficits. Neuroimaging, including non-contrast computed tomography (CT), magnetic resonance imaging (MRI), vascular and perfusion imaging, is a cornerstone in the diagnosis and treatment decision-making. This review examines the current state of evidence behind the different imaging paradigms for acute ischemic stroke diagnosis and treatment, including current recommendations from the guidelines. Non-contrast CT brain, or in some centers MRI, can help differentiate ischemic stroke and intracerebral hemorrhage (ICH), a pivotal juncture in stroke diagnosis and treatment algorithm, especially for early window thrombolytics. Advanced imaging such as MRI or perfusion imaging can also assist making a diagnosis of ischemic stroke versus mimics such as migraine, Todd's paresis, or functional disorders. Identification of medium-large vessel occlusions with CT or MR angiography triggers consideration of endovascular thrombectomy (EVT), with additional perfusion imaging help identify salvageable brain tissue in patients who are likely to benefit from reperfusion therapies, particularly in the ≥6 h window. We also review recent advances in neuroimaging and ongoing trials in key therapeutic areas and their imaging selection criteria to inform the readers on potential future transitions into use of neuroimaging for stroke diagnosis and treatment decision making. ANN NEUROL 2024;95:1017-1034.

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.

Safety and efficacy of magnesium-rich artificial cerebrospinal fluid for subarachnoid hemorrhage

Objectives

This study aimed to investigate the efficacy of using a newly formulated magnesium-rich artificial cerebrospinal fluid (MACSF) as an alternative to normal saline (NS) for intraoperative irrigation during aneurysm clipping in improving the prognosis of patients with Aneurysmal subarachnoid hemorrhage (aSAH).

Methods

Patients with aSAH who underwent intraoperative irrigation with MACSF or NS during the clipping in the First Affiliated Hospital of Xi 'an Jiaotong University from March 2019 to March 2022 were selected as MACSF group and NS group, respectively. The primary prognostic indicators were the incidence of favorable outcomes (mRS 0-2). The secondary outcome measures included cerebral vasospasm (CVS), mortality, total hospital stay, and intensive care unit (ICU) stay. Safety was evaluated based on the occurrence rates of hypermagnesemia, meningitis, and hydrocephalus.

Results

Overall, 34 and 37 patients were enrolled in the MACSF and NS groups, respectively. At 90 days after aSAH onset, the proportion of favorable prognosis in the MACSF group was significantly higher than that in the NS group (p = 0.035). The incidence of CVS within 14 days after surgery was significantly lower in the MACSF group than that in the NS group (p = 0.026). The mortality rate in the MACSF group was significantly lower than in the NS group (p = 0.048). The median lengths of hospital stay (p = 0.008) and ICU stay (p = 0.018) were significantly shorter in the MACSF group than in the NS group. No significant differences were observed in safety measures.

Conclusion

Using MACSF as an irrigation fluid for aneurysm clipping can significantly improve the 90-day prognosis of patients with aSAH, which may be related to the reduced incidence of CVS.

Clinical trial registration

https://www.clinicaltrials.gov, identifier NCT04358445.

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.

Effect of Emergency Green Channel Optimization on Ischemic Stroke Patients: Impact on Emergency Response Time, Effectiveness, Anxiety, and Acute Stress

Objective

The aim was to assess the effectiveness of an optimized emergency green channel in the treatment of acute ischemic stroke (AIS) patients and its effect on emergency response time, effectiveness, anxiety, and acute stress.

Methods

A retrospective analysis was conducted on 349 AIS patients treated with intravenous thrombolysis from January 2019 to May 2022. The patients were divided into those who received optimized emergency green channel treatment (155) and those who did not (194). Propensity score matching (PSM) was used to balance the admission pathways, living conditions, insurance methods, and residential locations of the 2 patient groups. The key metrics comprised the times from onset to admission, admission to computed tomography (CT), CT to thrombolysis, admission to thrombolysis (door-to-needle time (DNT)), National Institute of Health Stroke Scale (NIHSS) scores at various intervals post thrombolysis, heart rate, blood pressure, and scores in Self-Rating Anxiety Scale (SAS) and the Stanford Acute Stress Reaction Questionnaire (SASRQ).

Results

Post PSM, 118 patients were analyzed (54 control and 64 observation). The observation group showed significantly lower time results than the control group, which included the following: the time from onset to admission (t = 31.428, P < .001), door-to-imaging time (t = 27.317, P < .001), imaging-to-needle time (t = 20.951, P < .001, and DNT (t = 25.954, P < .001). Significant differences were observed in 24 hour-post thrombolysis NIHSS scores, heart rate, blood pressure, SAS, and SASRQ scores (P < .05) but not in NIHSS scores at 7 and 30 days.

Conclusion

The optimized emergency green channel process effectively reduced the treatment time for ischemic stroke patients, improved rescue efficiency, and positively influenced the psychological stress levels of patients post treatment.

The Influence of the Novel Computer-Aided Triage System Based on Artificial Intelligence on Endovascular Therapy in Patients with Large Vascular Occlusions: A Meta-Analysis

OBJECTIVE

The integration of artificial intelligence (AI) with modern healthcare has become increasingly prominent. The purpose of this study is to explore the impact of the novel computer-aided triage system based on artificial intelligence (AI-CTS) on endovascular therapy (EVT) in patients with large vascular occlusions (LVO). This study marks the first comprehensive systematic review and meta-analysis on the subject.

METHODS

A comprehensive study was performed on PubMed, Medline, Embase, Cochrane Library, and Chinese databases from their establishment to September 2023, in accordance with PRISMA recommendations. RevMan 5.4 software was used for summative analysis. The outcomes included door-to-groin (DTG) time, time from CT scan initiation to EVT, time from CT scan to reperfusion, and 90-day modified Rankin Scale (mRS).

RESULTS

A total of 7 studies involving 752 participants were included in the meta-analysis. The pooled results demonstrated that patients in the post-AI group had less time of DTG [SMD, 0.54; 95% CI, 0.40-0.69; P < 0.00001] and CT scan to EVT [SMD, 0.57; 95% CI, 0.42-0.73; P < 0.00001], as well as less time of CTA to recanalization [SMD, 0.63; 95% CI, 0.36-0.90; P < 0.00001]. There was no significant difference between the 2 groups in terms of the mRS at 90 days [OR, 0.66; 95% CI, 0.43-1.01; P = 0.06].

CONCLUSIONS

The combination of AI-CTS and EVT has improved the therapy process for LVO patients. However, the improvement in mRS at 90 days was not significant; further research is warranted.

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.

Hemiplegia in acute ischemic stroke: A comprehensive review of case studies and the role of intravenous thrombolysis and mechanical thrombectomy

Acute ischemic stroke is a significant health concern worldwide, often leading to long-term disability and decreased quality of life. Rapid and appropriate treatment is crucial for achieving optimal outcomes in these patients. Intravenous thrombolysis (IVT) and mechanical thrombectomy (MT) are two commonly used interventions for acute ischemic stroke, but their effectiveness in improving neurological symptoms and functional outcomes in patients with hemiplegia remains uncertain. The aim of this work was to evaluate the impact of IVT and MT within a 4.5-h time frame on patients with acute ischemic stroke and hemiplegia. A systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Relevant studies that assessed the impact of IVT and MT within 4.5-h on hemiplegia in patients with an acute ischemic stroke were included. Data were extracted and analyzed to determine the overall effects of these interventions. Most included case reports indicate positive outcomes in terms of neurological symptom improvement and functional recovery in patients with hemiplegia after receiving IVT and MT within the specified time frame. However, the heterogeneity among the patients and the limited use of IVT due to contraindications posed challenges in determining the most effective treatment option. The findings from the included studies demonstrate that both interventions led to a decrease in National Institutes of Health Stroke Scale scores, indicating an improvement in neurological symptoms. The results highlight the beneficial effects of early thrombolytic interventions and MT on the neurological status and functional outcomes of patients with an acute ischemic stroke.

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.

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.

AutoML accurately predicts endovascular mechanical thrombectomy in acute large vessel ischemic stroke

Background and objective

Automated machine learning or autoML has been widely deployed in various industries. However, their adoption in healthcare, especially in clinical settings is constrained due to a lack of clear understanding and explainability. The aim of this study is to utilize autoML for the prediction of functional outcomes in patients who underwent mechanical thrombectomy and compare it with traditional ML models with a focus on the explainability of the trained models.

Methods

A total of 156 patients of acute ischemic stroke with Large Vessel Occlusion (LVO) who underwent mechanical thrombectomy within 24 h of stroke onset were included in the study. A total of 34 treatment variables including clinical, demographic, imaging, and procedure-related data were extracted. Various conventional machine learning models such as decision tree classifier, logistic regression, random forest, kNN, and SVM as well as various autoML models such as AutoGluon, MLJAR, Auto-Sklearn, TPOT, and H2O were used to predict the modified Rankin score (mRS) at the time of patient discharge and 3 months follow-up. The sensitivity, specificity, accuracy, and AUC for traditional ML and autoML models were compared.

Results

The autoML models outperformed the traditional ML models. For the prediction of mRS at discharge, the highest testing accuracy obtained by traditional ML models for the decision tree classifier was 74.11%, whereas for autoML which was obtained through AutoGluon, it showed an accuracy of 88.23%. Similarly, for mRS at 3 months, the highest testing accuracy of traditional ML was that of the SVM classifier at 76.5%, whereas that of autoML was 85.18% obtained through MLJAR. The 24-h ASPECTS score was the most important predictor for mRS at discharge whereas for prediction of mRS at 3 months, the most important factor was mRS at discharge.

Conclusion

Automated machine learning models based on multiple treatment variables can predict the functional outcome in patients more accurately than traditional ML models. The ease of clinical coding and deployment can assist clinicians in the critical decision-making process. We have developed a demo application which can be accessed at https://mrs-score-calculator.onrender.com/.

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.

Advances in Acute Ischemic Stroke Treatment: Current Status and Future Directions

The management of acute ischemic stroke has undergone a paradigm shift in the past decade. This has been spearheaded by the emergence of endovascular thrombectomy, along with advances in medical therapy, imaging, and other facets of stroke care. Herein, we present an updated review of the various stroke trials that have impacted and continue to transform stroke management. It is critical for the radiologist to stay abreast of the ongoing developments to provide meaningful input and remain a useful part of the stroke team.

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.

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.

Visual review of acute stroke neuroimaging prior to transfer acceptance increases likelihood of endovascular therapy

OBJECTIVES

Demand for thrombectomy, and interhospital transfer to comprehensive stroke centers (CSCs), for acute stroke is increasing. There is an urgent need to identify patients most likely to benefit from transfer. We evaluated whether CSC providers' review of neuroimaging prior to transfer acceptance improved patient selection for thrombectomy and correlated with higher rates of treatment.

MATERIALS AND METHODS

A retrospective database of all patients transferred to Stanford's CSC for thrombectomy between 2015-2019 was used. Pre-acceptance images, when available for visual review, were reviewed by the CSC stroke team via virtual PACS, RAPID software, or LifeImage platforms.

RESULTS

525 patients met inclusion criteria. 147 (28%) had neuroimaging available for review prior to transfer. Of those who did not recanalize en route, 267 (50.8%) underwent thrombectomy. Patients with imaging available for review prior to acceptance were significantly more likely to receive thrombectomy (68% vs 54%, RR 1.26; p=0.006, 95% CI 1.09-1.48). Patient images that were reviewed via RAPID were CT-based perfusion studies; these were more likely to receive thrombectomy (70% vs 54%, RR 1.30; p=0.01, 1.09-1.56). Patients who received EVT were more likely to have had pre-transfer vessel imaging, regardless of availability for visual review (76% vs 59%, RR 1.44; p<0.001, 1.18-1.76).

CONCLUSIONS

Patients with concern for acute stroke transferred for consideration of thrombectomy who had neuroimaging visually reviewed prior to transfer acceptance and did not recanalize by time of arrival were significantly more likely to undergo thrombectomy. Additional prospective studies are needed to confirm our findings.

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.

Neuroimaging in Patient Selection for Thrombectomy, From the AJR Special Series on Emergency Radiology

Endovascular thrombectomy has become the standard-of-care treatment for carefully selected patients with acute ischemic stroke due to a large-vessel occlusion of the anterior circulation. Neuroimaging plays a vital role in determining patient eligibility for thrombectomy, both in the early (0-6 hours from symptom onset) and late (> 6 to 24 hours from symptom onset) time windows. Various neuroimaging algorithms are used to determine thrombectomy eligibility, and each algorithm must be optimized for institutional workflow. In this review, we describe common imaging modalities and recommended algorithms for the evaluation of patients for endovascular thrombectomy. We also discuss emerging patient populations who might qualify for thrombectomy in the coming years.

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.

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.

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.

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.

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.

VWF-targeted thrombolysis to overcome rh-tPA resistance in experimental murine ischemic stroke models

Recombinant human tissue plasminogen activator (rh-tPA) is an important thrombolytic agent for treatment of acute ischemic stroke. It requires fibrin binding for plasminogen activation. In contrast, Microlyse, a novel thrombolytic agent, requires von Willebrand factor (VWF) binding for plasminogen activation. We compared rh-tPA with Microlyse, administered 20 minutes after inducing thrombosis, in 2 randomized blinded acute ischemic stroke mouse models. Thrombosis was induced in the middle cerebral artery with different experimental triggers. Where thrombin infusion generates fibrin-rich thrombi, topical FeCl3 application generates platelet-rich thrombi. In the fibrin-rich model, both rh-tPA and Microlyse increased cortical reperfusion (determined by laser speckle imaging) 10 minutes after therapy administration (35.8 ± 17.1%; P = .001 39.3 ± 13.1%; P < .0001; 15.6 ± 7.5%, respectively, vs vehicle). In addition, both thrombolytic agents reduced cerebral lesion volume (determined by magnetic resonance imaging) after 24 hours (18.9 ± 11.2 mm3; P = .033; 16.1 ± 13.9 mm3; P = .018; 26.6 ± 5.6 mm3, respectively, vs vehicle). In the platelet-rich model, neither rh-tPA nor Microlyse increased cortical reperfusion 10 minutes after therapy (7.6 ± 8.8%; P = .216; 16.3 ± 13.9%; P = .151; 10.1 ± 7.9%, respectively, vs vehicle). However, Microlyse, but not rh-tPA, decreased cerebral lesion volumes (13.9 ± 11.4 mm3; P < .001; 23.6 ± 11.1 mm3; P = .188; 30.3 ± 10.9 mm3, respectively, vs vehicle). These findings support broad applicability of Microlyse in ischemic stroke, irrespective of the thrombus composition.

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.

Impact of time between thrombolysis and endovascular thrombectomy on outcomes in patients with acute ischaemic stroke

BACKGROUND

Benefits of endovascular thrombectomy (ET) after intravenous thrombolysis (IVT) for patients with acute ischaemic stroke (AIS) have been demonstrated, but analyses of the relationship between IVT-ET time delay and functional outcomes among patients receiving both treatments are lacking.

METHODS

We used data from the "Berlin-Specific Acute Treatment in Ischaemic and haemorrhAgic stroke with Long-term outcome" (B-SPATIAL) registry. Between January 1st, 2016 and December 31st, 2019, we included patients who received both IVT and ET. The primary outcome was the 3-month ordinal modified Rankin scale (mRS) score. The IVT-ET time delay was analyzed in categories and continuously. We used adjusted ordinal logistic regression to estimate common odds ratios (cOR) and 95% confidence intervals (CI). Secondary analyses involved flexible modeling of IVT-ET delay and dichotomous outcomes.

RESULTS

Of 11,049 patients, 714 who received IVT followed by ET were included. Compared with having an IVT-ET window >120 min (reference), for an IVT-ET window < 30 min, we obtained adjusted cORs for mRS of 0.41 (95% CI: 0.22 to 0.78); and 0.52 (95% CI: 0.33 to 0.82) for 30 to 120 min. Secondary analyses also found protective effects of shorter time delays against "poor" functional outcomes at 3 months.

CONCLUSIONS

In patients with AIS, shorter IVT-ET intervals were associated with better 3-month functional outcomes. While the time-to-IVT and time-to-ET include the time until medical attention is received, the IVT-ET time delays fall entirely within the domain of medical management and thus might be easier to optimize.

Flow augmentation STA-MCA bypass evaluation for patients with acute stroke and unilateral large vessel occlusion: a proposal for an urgent bypass flowchart

OBJECTIVE

Endovascular recanalization trials have shown a positive impact on the preservation of ischemic penumbra in patients with acute large vessel occlusion (LVO). The concept of penumbra salvation can be extended to surgical revascularization with bypass in highly selected patients. For selecting these patients, the authors propose a flowchart based on multimodal MRI.

METHODS

All patients with acute stroke and persisting internal carotid artery (ICA) or M1 occlusion after intravenous lysis or mechanical thrombectomy undergo advanced neuroimaging in a time window of 72 hours after stroke onset including perfusion MRI, blood oxygenation level-dependent functional MRI to evaluate cerebrovascular reactivity (BOLD-CVR), and noninvasive optimal vessel analysis (NOVA) quantitative MRA to assess collateral circulation.

RESULTS

Symptomatic patients exhibiting persistent hemodynamic impairment and insufficient collateral circulation could benefit from bypass surgery. According to the flowchart, a bypass is considered for patients 1) with low or moderate neurological impairment (National Institutes of Health Stroke Scale score 1-15, modified Rankin Scale score ≤ 3), 2) without large or malignant stroke, 3) without intracranial hemorrhage, 4) with MR perfusion/diffusion mismatch > 120%, 5) with paradoxical BOLD-CVR in the occluded vascular territory, and 6) with insufficient collateral circulation.

CONCLUSIONS

The proposed flowchart is based on the patient's clinical condition and multimodal MR neuroimaging and aims to select patients with acute stroke due to LVO and persistent inadequate collateral flow, who could benefit from urgent bypass.

What You Always Wanted to Know about Endovascular Therapy in Acute Ischemic Stroke but Never Dared to Ask: A Comprehensive Review

In 2015, mechanical thrombectomy (MT) in combination with intravenous thrombolysis was demonstrated to be superior to best medical treatment alone in patients with anterior circulation stroke. This finding resulted in an unprecedented boost in endovascular stroke therapy, and MT became widely available. MT was initially approved for patients presenting with large vessel occlusion in the anterior circulation (intracranial internal carotid artery or proximal middle cerebral artery) within a 6-hour time window. Eventually, it was shown to be beneficial in a broader group of patients, including those without known symptom-onset, wake-up stroke, or patients with posterior circulation stroke. Technical developments and the implementation of novel thrombectomy devices further facilitated endovascular recanalization for acute ischemic stroke. However, some aspects remain controversial. Is MT suitable for medium or very distal vessel occlusions? Should emergency stenting be performed for symptomatic stenosis or recurrent occlusion? How should patients with large vessel occlusion without disabling symptoms be treated? Do certain patients benefit from MT without intravenous thrombolysis? In the era of personalized decision-making, some of these questions require an individualized approach based on comorbidities, imaging criteria, and the severity or duration of symptoms. Despite its successful development in the past decade, endovascular stroke therapy will remain a challenging and fascinating field in the years to come. This review aims to provide an overview of patient selection, and the indications for and execution of MT in patients with acute ischemic stroke.

Retrograde Angiography to Detect Dropped Thrombus in Mechanical Thrombectomy

OBJECTIVE

The risk of embolization to distal territory or to new territory in mechanical thrombectomy remains a major issue despite advancements in technological device. This condition can be caused by a large and firm dropped thrombus without passing through a guiding catheter during stent retriever or aspiration catheter withdrawal. This report introduced a novel technique referred to as retrograde angiography to detect dropped thrombus.

METHODS

The retrograde angiography to detect dropped thrombus technique is a kind of retrograde angiography that consists of a contrast medium injection via a distal microcatheter and aspiration through an inflated balloon-guiding catheter. This method was used to detect dropped thrombus at the balloon-guiding catheter tip when back flow was blocked from the balloon-guiding catheter after stent retriever or aspiration catheter withdrawal. We retrospectively reviewed four consecutive patients who underwent the retrograde angiography to detect dropped thrombus technique during mechanical thrombectomy for acute ischemic stroke due to large vessel occlusion in the anterior circulation between January 2018 and January 2021.

RESULTS

Three of four patients had dropped thrombus, which was diagnosed with the technique and retrieved completely with subsequent procedures while maintaining the balloon-guiding catheter inflated. None of the patients experienced embolization to distal territory/embolization to new territory, and a successful reperfusion was achieved in all four cases.

CONCLUSIONS

The retrograde angiography to detect dropped thrombus is a technique to detect a dropped thrombus at the balloon-guiding catheter tip and allows us to retrieve it with subsequent mechanical thrombectomy procedures while maintaining the balloon-guiding catheter inflated and it may be useful for reducing the risk of embolization to distal territory/embolization to new territory.

Use of evidence in acute stroke decision-making: Implications for evidence-based medicine

RATIONALE, AIMS AND OBJECTIVES

Evidence-Based Medicine proposes a prescriptive model of physician decision-making in which 'best evidence' is used to guide best practice. And yet, proponents of EBM acknowledge that EBM fails to offer a systematic theory of physician decision-making.

METHODS

In this paper, we explore how physicians from the neurology and emergency medicine communities have responded to an evolving body of evidence surrounding the acute treatment of patients with ischemic stroke. Through analysis of this case study, we argue that EBM's vision of evidence-based medical decision-making fails to appreciate a process that we have termed epistemic evaluation.

RESULTS AND CONCLUSIONS

Physicians are required to interpret and apply any knowledge-even what EBM would term 'best evidence'-in light of their own knowledge, background and experience. This is consequential for EBM as understanding what physicians do and why they do it would appear to be essential to achieving optimal practice in accordance with best evidence.

Frictional force analysis of stent retriever devices using a realistic vascular model: Pilot study

Objective

To date, no vascular model to analyze frictional forces between stent retriever devices and vessel walls has been designed to be similar to the real human vasculature. We developed a novel in vitro intracranial cerebrovascular model and analyzed frictional forces of three stent retriever devices.

Methods

A vascular mold was created based on digital subtraction angiography of a patient's cerebral vessels. The vascular model was constructed using polydimethylsiloxane (PDMS, Dow Corning, Inc.) as a silicone elastomer. The vascular model was coated on its inner surface with a lubricating layer to create a low coefficient of friction (~0.037) to closely approximate the intima. A pulsatile blood pump was used to produce blood flow inside the model to approximate real vascular conditions. The frictional forces of Trevo XP, Solitaire 2, and Eric 4 were analyzed for initial and maximal friction retrieval forces using this vascular model. The total pulling energy generated during the 3 cm movement was also obtained.

Results

Results for initial retrieval force were as follows: Trevo, 0.09 ± 0.04 N; Solitaire, 0.25 ± 0.07 N; and Eric, 0.33 ± 0.21 N. Results for maximal retrieval force were as follows: Trevo, 0.36 ± 0.07 N; Solitaire, 0.54 ± 0.06 N; and Eric, 0.80 ± 0.13 N. Total pulling energy (N·cm) was 0.40 ± 0.10 in Trevo, 0.65 ± 0.10 in Solitaire, and 0.87 ± 0.14 in Eric, respectively.

Conclusions

Using a realistic vascular model, different stent retriever devices were shown to have statistically different frictional forces. Future studies using a realistic vascular model are warranted to assess SRT devices.

Burden of stroke in North Africa and Middle East, 1990 to 2019: a systematic analysis for the global burden of disease study 2019

BACKGROUND

While several studies investigated the epidemiology and burden of stroke in the North Africa and Middle East region, no study has comprehensively evaluated the age-standardized attributable burden to all stroke subtypes and their risk factors yet.

OBJECTIVE

The aim of the present study is to explore the regional distribution of the burden of stroke, including ischemic stroke, subarachnoid hemorrhage, and intracerebral hemorrhage, and the attributable burden to its risk factors in 2019 among the 21 countries of North Africa and Middle East super-region.

METHODS

The data of the Global Burden of Disease Study (GBD) 2019 on stroke incidence, prevalence, death, disability-adjusted life years (DALYs), years of life lost (YLLs), years lived with disability (YLDs) rates, and attributed deaths, DALYs, YLLs, and YLDs to stroke risk factors were used for the present study.

RESULTS

The age-standardized deaths, DALYs, and YLLs rates were diminished statistically significant by 27.8, 32.0, and 35.1% from 1990 to 2019, respectively. Attributed deaths, DALYs, and YLLs to stroke risk factors, including high systolic blood pressure, high body-mass index, and high fasting plasma glucose shrank statistically significant by 24.9, 25.8, and 28.8%, respectively.

CONCLUSION

While the age-standardized stroke burden has reduced during these 30 years, it is still a concerning issue due to its increased burden in all-age numbers. Well-developed primary prevention, timely diagnosis and management of the stroke and its risk factors might be appreciated for further decreasing the burden of stroke and its risk factors and reaching Sustainable Development Goal 3.4 target for reducing premature mortality from non-communicable diseases.

Reperfusion therapy in acute ischemic stroke

Background: Until mid-2010, intravenous thrombolysis remains the only reperfusion therapy for acute ischemic stroke. In 2015, the five pivotal endovascular recanalization therapy (ERT) trials demonstrated that ERT improved the prognosis of acute ischemic stroke with large artery occlusion within 6 hours after onset. Currently, ERT has been established as a crucial acute ischemic stroke treatment option. The prognosis of acute ischemic stroke is known to be time-dependent. Several studies addressed that ERT expands the time window for reperfusion therapy; thereby, improving prognosis.Current Concepts: Recent randomized clinical trials revealed that ERT improved the outcome in patients even within the late time window of up to 24 hours of stroke onset. The trials enrolled participants who had target mismatch, defined as either clinical-core or perfusion-core mismatch, which prompted an update of the national guidelines in several countries. To select the patients with stroke who were eligible for ERT, advanced imaging tools could be recommended.Discussion and Conclusion: According to the updated ERT guidelines, stroke centers were recommended to establish an appropriate imaging protocol and strategy for patients with acute ischemic stroke who were within the late time window. Additionally, if ERT is further practiced nationally, more manpower and infrastructure for patients with stroke should be supported at the stroke center.

Acute Neurointervention for Ischemic Stroke

Acute ischemic stroke (AIS) is one of the major causes of death worldwide and a leading cause of disability. Until recently treatment of AIS was supportive, and in a minority of patients intravenous thrombolysis was available but with marginal clinical benefit. With the advent of stent retrievers, distal aspiration catheters as well as improved patient selection neurologic outcomes have greatly improved. However, the care of patients with AIS is still challenging and requires the early recognition of stroke symptoms, extensive diagnostic testing, early intervention, and advanced nursing and critical care.

A clinically relevant model of focal embolic cerebral ischemia by thrombus and thrombolysis in rhesus monkeys

Over decades of research into the treatment of stroke, nearly all attempts to translate experimental treatments from discovery in cells and rodents to use in humans have failed. The prevailing belief is that it might be necessary to pretest pharmacological neuroprotection in higher-order brains, especially those of nonhuman primates (NHPs). Over the past few years, chemical thrombolysis and mechanical thrombectomy have been established as the standard of care for ischemic stroke in patients. The spotlight is now shifting towards emphasizing both focal ischemia and subsequent reperfusion in developing a clinically relevant stroke model in NHPs. This protocol describes an embolic model of middle cerebral artery occlusion in adult rhesus monkeys. An autologous clot is combined with a microcatheter or microwire through endovascular procedures, and reperfusion is achieved through local intra-artery thrombolysis with tissue plasminogen activator. These NHP models formed relatively stable infarct sizes, delivered predictable reperfusion and survival outcomes, and recapitulated key characteristics of patients with ischemic stroke as observed on MRI images and behavioral assays. Importantly, treated animals could survive 30 d after the surgery for post-stroke neurologic deficit analyses. Thus far, this model has been used in several translational studies. Here we describe in detail the teamwork necessary for developing stroke models of NHPs, including the preoperation preparations, endovascular surgery, postoperation management and histopathological analysis. The model can be established by the following procedures over a 45-d period, including preparation steps (14 d), endovascular operation (1 d) and evaluation steps (30 d).

Detection, Diagnosis and Treatment of Acute Ischemic Stroke: Current and Future Perspectives

Stroke is one of the leading causes of disability worldwide. Early diagnosis and treatment of stroke are important for better clinical outcome. Rapid and accurate diagnosis of stroke subtypes is critical. This review discusses the advantages and disadvantages of the current diagnostic and assessment techniques used in clinical practice, particularly for diagnosing acute ischemic stroke. Alternative techniques for rapid detection of stroke utilizing blood based biomarkers and novel portable devices employing imaging methods such as volumetric impedance phase-shift spectroscopy, microwave tomography and Doppler ultrasound are also discussed. Current therapeutic approaches for treating acute ischemic stroke using thrombolytic drugs and endovascular thrombectomy are discussed, with a focus on devices and approaches recently developed to treat large cranial vessel occlusions.

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.

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.

Practicalities of Impracticability: An Interim Review of Randomized Controlled Trials

Impracticability is an ethical standard for waiver of informed consent in research. We examine how well the criterion of impracticability appears to have been fulfilled in a set of 36 completed randomized controlled trials (RCTs) that secured consent from some subjects or LARs and employed waivers to enroll others. These trials were identified among 155 RCTs using waivers of consent in a convenience sample drawn from 7 systematic reviews. Recruitment data were available for 19 of the 36 trials, revealing an average of 41.6% of subjects (range 0.2-98.7%, 95% CI: 24.8-58.4%) were enrolled without consent. Six trials enrolled less than 10% of subjects without consent and an overlapping set of 9 trials sought consent from all subjects or LARs at some sites while waiving consent at other sites. We question whether these trials were practicable without waivers and identify issues for consideration by investigators and ethics review boards.

Ferroptosis—A Novel Mechanism With Multifaceted Actions on Stroke

As a neurological disease with high morbidity, disability, and mortality, the pathological mechanism underlying stroke involves complex processes such as neuroinflammation, oxidative stress, apoptosis, autophagy, and excitotoxicity; but the related research on these molecular mechanisms has not been effectively applied in clinical practice. As a form of iron-dependent regulated cell death, ferroptosis was first discovered in the pathological process of cancer, but recent studies have shown that ferroptosis is closely related to the onset and development of stroke. Therefore, a deeper understanding of the relationship between ferroptosis and stroke may lead to more effective treatment strategies. Herein, we reviewed the mechanism(s) underlying the onset of ferroptosis in stroke, the potential role of ferroptosis in stroke, and the crosstalk between ferroptosis and other pathological mechanisms. This will further deepen our understanding of ferroptosis and provide new approaches to the treatment of stroke.

Association of Acute Alteration of Consciousness in Patients With Acute Ischemic Stroke With Outcomes and Early Withdrawal of Care

BACKGROUND AND OBJECTIVES

Early consciousness disorder (ECD) after acute ischemic stroke (AIS) is understudied. ECD may influence outcomes and the decision to withhold or withdraw life-sustaining treatment.

METHODS

We studied patients with AIS from 2010 to 2019 across 122 hospitals participating in the Florida Stroke Registry. We studied the effect of ECD on in-hospital mortality, withholding or withdrawal of life-sustaining treatment (WLST), ambulation status on discharge, hospital length of stay, and discharge disposition.

RESULTS

Of 238,989 patients with AIS, 32,861 (14%) had ECD at stroke presentation. Overall, average age was 72 years (Q1 61, Q3 82), 49% were women, 63% were White, 18% were Black, and 14% were Hispanic. Compared to patients without ECD, patients with ECD were older (77 vs 72 years), were more often female (54% vs 48%), had more comorbidities, had greater stroke severity as assessed by the National Institutes of Health Stroke Scale (score ≥5 49% vs 27%), had higher WLST rates (21% vs 6%), and had greater in-hospital mortality (9% vs 3%). Using adjusted models accounting for basic characteristics, patients with ECD had greater in-hospital mortality (odds ratio [OR] 2.23, 95% CI 1.98-2.51), had longer hospitalization (OR 1.37, 95% CI 1.33-1.44), were less likely to be discharged home or to rehabilitation (OR 0.54, 95% CI 0.52-0.57), and were less likely to ambulate independently (OR 0.61, 95% CI 0.57-0.64). WLST significantly mediated the effect of ECD on mortality (mediation effect 265; 95% CI 217-314). In temporal trend analysis, we found a significant decrease in early WLST (<2 days) (R² 0.7, p = 0.002) and an increase in late WLST (≥2 days) (R² 0.7, p = 0.004).

DISCUSSION

In this large prospective multicenter stroke registry, patients with AIS presenting with ECD had greater mortality and worse discharge outcomes. Mortality was largely influenced by the WLST decision.