Endovascular Thrombectomy in Acute Ischemic Stroke

Hypoperfusion intensity ratio correlates with collaterals and predicts outcome and infarct volume in acute ischemic stroke patients

BACKGROUND

Hypoperfusion Intensity Ratio (HIR) is associated with collaterals and outcome in acute ischemic stroke (AIS). We investigated whether a combined assessment of HIR and collaterals could provide an added value.

METHODS

Retrospective single-center study, including AIS patients with large vessel occlusion and endovascular treatment 0-24 h from onset. Predictors of FIV and outcome (90 days modified Rankin Scale 0-1) were investigated with linear and logistic regression respectively. Subjects were stratified in three groups: poor collaterals (grade 0-3) with poor HIR (≥.4), good collaterals (grade 4-5) with poor HIR/poor collaterals with good HIR (<.4) and good collaterals with good HIR.

RESULTS

We included 337 patients (median age 77, 53.1% males), of whom 100 (29.7%) had excellent outcome. One hundred and forty five patients with favourable collateral and HIR profiles had smaller infarct (median poor collaterals with poor HIR 41 mL, good collaterals with poor HIR/poor collaterals with good HIR 21 mL and good collaterals with good HIR 11 mL, p <.001) and higher rates of excellent outcome (poor collaterals with poor HIR 15.7%, good collaterals with poor HIR/poor collaterals with good HIR 26.2% and good collaterals with good HIR 39.3% p =.001). Logistic regression showed that patients with favourable collateral and HIR profiles had the highest odds of good outcome (OR: 3.83, 95% CI 1.62-9.08, p =.002).

CONCLUSION

Collaterals and HIR are independent predictors of final infarct lesion and outcome in stroke patients and their integration provides an added value. These findings might inform clinical practice and future trials.

A Review of Post-Stroke Cognitive Impairment and the Potential Benefits of Stingless Bee Honey Supplementation

Post-stroke cognitive impairment (PSCI) is a common decline in cognitive abilities that occurs within 3 months after a stroke. During recovery, stroke survivors often experience varying degrees of cognitive decline, with some patients experiencing permanent cognitive deficits. Thus, it is crucial to prioritise recovery and rehabilitation after a stroke to promote optimal protection of and improvement in cognitive function. Honey derived from stingless bees has been linked to various therapeutic properties, including neuroprotective effects. However, scientific evidence for the mechanisms through which these honey supplements enhance cognitive function remains limited. This narrative review aims to provide an overview of the causes of PSCI, current treatments, the biomarkers influencing cognition in post-stroke patients and the potential of stingless bee honey (SBH) as a neuroprotective agent against the progression of PSCI.

Embolic strokes of undetermined source: a clinical consensus statement of the ESC Council on Stroke, the European Association of Cardiovascular Imaging and the European Heart Rhythm Association of the ESC

One in six ischaemic stroke patients has an embolic stroke of undetermined source (ESUS), defined as a stroke with unclear aetiology despite recommended diagnostic evaluation. The overall cardiovascular risk of ESUS is high and it is important to optimize strategies to prevent recurrent stroke and other cardiovascular events. The aim of clinicians when confronted with a patient not only with ESUS but also with any other medical condition of unclear aetiology is to identify the actual cause amongst a list of potential differential diagnoses, in order to optimize secondary prevention. However, specifically in ESUS, this may be challenging as multiple potential thromboembolic sources frequently coexist. Also, it can be delusively reassuring because despite the implementation of specific treatments for the individual pathology presumed to be the actual thromboembolic source, patients can still be vulnerable to stroke and other cardiovascular events caused by other pathologies already identified during the index diagnostic evaluation but whose thromboembolic potential was underestimated. Therefore, rather than trying to presume which particular mechanism is the actual embolic source in an ESUS patient, it is important to assess the overall thromboembolic risk of the patient through synthesis of the individual risks linked to all pathologies present, regardless if presumed causally associated or not. In this paper, a multi-disciplinary panel of clinicians/researchers from various backgrounds of expertise and specialties (cardiology, internal medicine, neurology, radiology and vascular surgery) proposes a comprehensive multi-dimensional assessment of the overall thromboembolic risk in ESUS patients through the composition of individual risks associated with all prevalent pathologies.

Intranasal Delivery of Mitochondria Attenuates Brain Injury by AMPK and SIRT1/PGC-1α Pathways in a Murine Model of Photothrombotic Stroke

Ischemic stroke is one of the major causes of morbidity and mortality worldwide. Mitochondria play a vital role in the pathological processes of cerebral ischemic injury, but its transplantation and underlying mechanisms remain unclear. In the present study, we examined the effects of mitochondrial therapy on the modulation of AMPK and SIRT1/PGC-1α signaling pathway, oxidative stress, and NLRP3 inflammasome activation after photothrombotic ischemic stroke (pt-MCAO). The adult male mice were subjected to the pt-MCAO in which the proximal-middle cerebral artery was exposed with a 532-nm laser beam for 4 min by retro-orbital injection of a photosensitive dye (Rose Bengal: 15 mg/kg) before the laser light exposure and isolated mitochondria (100 μg protein) were administered intranasally at 30 min, 24 h, and 48 h following post-stroke. After 72 h, mice were tested for neurobehavioral outcomes and euthanized for infarct volume, brain edema, and molecular analysis. First, we found that mitochondria therapy significantly decreased brain infarct volume and brain edema, improved neurological dysfunction, attenuated ischemic stroke-induced oxidative stress, and neuroinflammation. Second, mitochondria treatment inhibited NLRP3 inflammasome activation. Finally, mitochondria therapy accelerated p-AMPKα(Thr172) and PGC-1α expression and resorted SIRT1 protein expression levels in pt-MCAO mice. In conclusion, our results demonstrate that mitochondria therapy exerts neuroprotective effects by inhibiting oxidative damage and inflammation, mainly dependent on the heightening activation of the AMPK and SIRT1/PGC-1α signaling pathway. Thus, intranasal delivery of mitochondria might be considered a new therapeutic strategy for ischemic stroke treatment.

Neuroprotective effects of oral metformin before stroke on cerebral small-vessel disease

BACKGROUND

Metformin (MET) treatment prior to stroke might have neuroprotective effects other than hypoglycemic effects. This study evaluated whether MET treatment prior to stroke is associated with neurological severity and functional outcome in patients with stroke who were not indicated for endovascular treatment and whether the effects of MET differ for each ischemic stroke subtype.

METHODS

We investigated 160 type 2 diabetes mellitus patients with ischemic stroke without endovascular treatment who were taking some oral antidiabetic agents prior to stroke in two tertiary hospitals. Lower neurological severity was defined as a National Institutes of Health Stroke Scale score of 3 or lower on admission, and favorable functional outcome was defined as a modified Rankin Scale score = 0-2 at discharge. We analyzed the effects of MET on the neurological severity and functional outcome in each ischemic stroke subtype on logistic regression analysis with adjustments for multiple confounding factors.

RESULTS

MET treatment prior to stroke was associated with lower stroke severity and favorable functional outcome. In the stroke subtypes, MET use affected both neurological severity (P = 0.037) and functional outcome (P = 0.041) in only patients with small-vessel disease (SVD).

CONCLUSIONS

MET may be useful to improve the outcome of patients with SVD.

Selenium Nanoparticles in Protecting the Brain from Stroke: Possible Signaling and Metabolic Mechanisms

Strokes rank as the second most common cause of mortality and disability in the human population across the world. Currently, available methods of treating or preventing strokes have significant limitations, primarily the need to use high doses of drugs due to the presence of the blood-brain barrier. In the last decade, increasing attention has been paid to the capabilities of nanotechnology. However, the vast majority of research in this area is focused on the mechanisms of anticancer and antiviral effects of nanoparticles. In our opinion, not enough attention is paid to the neuroprotective mechanisms of nanomaterials. In this review, we attempted to summarize the key molecular mechanisms of brain cell damage during ischemia. We discussed the current literature regarding the use of various nanomaterials for the treatment of strokes. In this review, we examined the features of all known nanomaterials, the possibility of which are currently being studied for the treatment of strokes. In this regard, the positive and negative properties of nanomaterials for the treatment of strokes have been identified. Particular attention in the review was paid to nanoselenium since selenium is a vital microelement and is part of very important and little-studied proteins, e.g., selenoproteins and selenium-containing proteins. An analysis of modern studies of the cytoprotective effects of nanoselenium made it possible to establish the mechanisms of acute and chronic protective effects of selenium nanoparticles. In this review, we aimed to combine all the available information regarding the neuroprotective properties and mechanisms of action of nanoparticles in neurodegenerative processes, especially in cerebral ischemia.

Evaluating a Novel EEG-Based Index for Stroke Detection Under Anesthesia During Mechanical Thrombectomy

BACKGROUND

The rapid identification of acute stroke (AS) during and after anesthesia might lead to early interventions and improved outcomes. We investigated a novel 2-channel electroencephalogram (EEG)-based marker for stroke detection-the lateral interconnection ratio (LIR)-in AS patients having endovascular thrombectomy (EVT) with general anesthesia (GA) or sedation. The LIR in 2 reference groups of patients without postoperative neurological complications was used for comparison.

METHODS

The National Institutes of Health stroke scale score was assessed before and after thrombectomy in 100 patients having EVT with GA or sedation. The EEG was monitored during and for 4 hours following EVT in the AS group and during surgery in the 2 reference groups. We compared: (1) LIR between AS and reference groups; (2) LIR and stroke dynamics (clinical improvement or deterioration after EVT assessed by the National Institutes of Health stroke scale score); (3) the impact of stroke site (anterior vs. posterior circulation) and anesthesia type (GA vs. sedation) on the LIR.

RESULTS

Median (interquartile range) LIR was lower in patients with AS compared with reference patients (0.09, 0.05 to 0.16 vs. 0.39, 0.24 to 0.52, respectively; P <0.000002), and LIR increased in AS patients whose clinical status recovered after EVT compared with nonrecovered patients (0.20, 0.12 to 0.29 vs. 0.09, 0.05 to 0.11, respectively; P <0.007). The LIR might be more sensitive to anterior circulation stroke but is not impacted by anesthesia type.

CONCLUSIONS

We demonstrated the utility of using AS patients undergoing EVT as a platform for assessing a novel EEG marker for the identification of stroke during anesthesia. Further, large-scale studies in AS patients during EVT and in patients undergoing different surgeries and anesthesia are required to validate the LIR.

Artificial intelligence-driven ASPECTS for the detection of early stroke changes in non-contrast CT: a systematic review and meta-analysis

BACKGROUND

Recent advances in machine learning have enabled development of the automated Alberta Stroke Program Early CT Score (ASPECTS) prediction algorithms using non-contrast enhanced computed tomography (NCCT) scans. The applicability of automated ASPECTS in daily clinical practice is yet to be established. The objective of this meta-analysis was to directly compare the performance of automated and manual ASPECTS predictions in recognizing early stroke changes on NCCT.

METHODS

The MEDLINE, Scopus, and Cochrane databases were searched. The last database search was performed on March 10, 2022. Studies reporting the diagnostic performance and validity of automated ASPECTS software compared with expert readers were included. The outcomes were the interobserver reliability of outputs between ASPECTS versus expert readings, experts versus reference standard, and ASPECTS versus reference standard by means of pooled Fisher's Z transformation of the interclass correlation coefficients (ICCs).

RESULTS

Eleven studies were included in the meta-analysis, involving 1976 patients. The meta-analyses showed good interobserver reliability between experts (ICC 0.72 (95% CI 0.63 to 0.79); p<0.001), moderate reliability in the correlation between automated and expert readings (ICC 0.54 (95% CI 0.40 to 0.67); p<0.001), good reliability between the total expert readings and the reference standard (ICC 0.62 (95% CI 0.52 to 0.71); p<0.001), and good reliability between the automated predictions and the reference standard (ICC 0.72 (95% CI 0.61 to 0.80); p<0.001).

CONCLUSIONS

Artificial intelligence-driven ASPECTS software has comparable or better performance than physicians in terms of recognizing early stroke changes on NCCT.

The Application of Data Envelopment Analysis to Emergency Departments and Management of Emergency Conditions: A Narrative Review

The healthcare industry is one application for data envelopment analysis (DEA) that can have significant benefits for standardizing health service delivery. This narrative review focuses on the application of DEA in emergency departments (EDs) and the management of emergency conditions such as acute ischemic stroke and acute myocardial infarction (AMI). This includes benchmarking the proportion of patients that receive treatment for these emergency conditions. The most frequent primary areas of study motivating work in DEA, EDs and management of emergency conditions including acute management of stroke are sorted into five distinct clusters in this study: (1) using basic DEA models for efficiency analysis in EDs, i.e., applying variable return to scale (VRS), or constant return to scale (CRS) to ED operations; (2) combining advanced and basic DEA approaches in EDs, i.e., applying super-efficiency with basic DEA or advanced DEA approaches such as additive model (ADD) and slack-based measurement (SBM) to clarify the dynamic aspects of ED efficiency throughout the duration of a first-aid program for AMI or heart attack; (3) applying DEA time series models in EDs like the early use of thrombolysis and percutaneous coronary intervention (PCI) in AMI treatment, and endovascular thrombectomy (EVT) in acute ischemic stroke treatment, i.e., using window analysis and Malmquist productivity index (MPI) to benchmark the performance of EDs over time; (4) integrating other approaches with DEA in EDs, i.e., combining simulations, machine learning (ML), multi-criteria decision analysis (MCDM) by DEA to reduce patient waiting times, and futile transfers; and (5) applying various DEA models for the management of acute ischemic stroke, i.e., using DEA to increase the number of eligible acute ischemic stroke patients receiving EVT and other medical ischemic stroke treatment in the form of thrombolysis (alteplase and now Tenecteplase). We thoroughly assess the methodological basis of the papers, offering detailed explanations regarding the applied models, selected inputs and outputs, and all relevant methodologies. In conclusion, we explore several ways to enhance DEA's status, transforming it from a mere technical application into a strong methodology that can be utilized by healthcare managers and decision-makers.

Dual-Energy Computed Tomography in Stroke Imaging : Value of a New Image Acquisition Technique for Ischemia Detection after Mechanical Thrombectomy

OBJECTIVE

To assess if a new dual-energy computed tomography (DECT) technique enables an improved visualization of ischemic brain tissue after mechanical thrombectomy in acute stroke patients.

MATERIAL AND METHODS

The DECT head scans with a new sequential technique (TwinSpiral DECT) were performed in 41 patients with ischemic stroke after endovascular thrombectomy and were retrospectively included. Standard mixed and virtual non-contrast (VNC) images were reconstructed. Infarct visibility and image noise were assessed qualitatively by two readers using a 4-point Likert scale. Quantitative Hounsfield units (HU) were used to assess density differences of ischemic brain tissue versus healthy tissue on the non-affected contralateral hemisphere.

RESULTS

Infarct visibility was significantly better in VNC compared to mixed images for both readers R1 (VNC: median 1 (range 1-3), mixed: median 2 (range 1-4), p < 0.05) and R2 (VNC: median 2 (range 1-3), mixed: 2 (range 1-4), p < 0.05). Qualitative image noise was significantly higher in VNC compared to mixed images for both readers R1 (VNC: median 3, mixed: 2) and R2 (VNC: median 2, mixed: 1, p < 0.05, each). Mean HU were significantly different between the infarcted tissue and the reference healthy brain tissue on the contralateral hemisphere in VNC (infarct 24 ± 3) and mixed images (infarct 33 ± 5, p < 0.05, each). The mean HU difference between ischemia and reference in VNC images (mean 8 ± 3) was significantly higher (p < 0.05) compared to the mean HU difference in mixed images (mean 5 ± 4).

CONCLUSION

TwinSpiral DECT allows an improved qualitative and quantitative visualization of ischemic brain tissue in ischemic stroke patients after endovascular treatment.

Rehabilitation in Animal Models of Stroke

OBJECTIVE

The purpose of this review was to evaluate the efficacy of rehabilitation strategies in animal models of stroke and their correlation with human stroke studies.

METHODS

General description of a stroke, functional recovery, and rehabilitation modalities were included from published studies in the field of animal models of cerebral ischemia and ischemia-reperfusion.

RESULTS

In stroke survivors, rehabilitation plays a significant role to improve motor function, cognition, and other subtle behaviors. Targeted pharmacological agents, including neuroprotective drugs, are helpful in animal models of stroke. However, no drug has yet been found that meets the criteria that would make it the Food and Drug Administration-approved treatment for human stroke. Instead, the rehabilitation of stroke in humans is limited to physical and occupational therapy, speech therapy, environmental enrichment, and social activities, as well as spiritual and family support.

CONCLUSION

Studies on stroke injury and the significance of stroke animals' rehabilitation, including physical and pharmacological, approaches are highlighted.

Post-stroke cardiovascular management: Current concepts, integrated care and future developments

After an ischaemic stroke patients often have cardiovascular complications known as stroke-heart syndrome. The cardiovascular management after stroke has a significant impact on life expectancy as well as the quality of life. The development and implementation of management pathways to improve outcomes for patients with stroke-heart syndrome requires a multidisciplinary involvement from health care professionals from primary, secondary and tertiary prevention levels. A holistic, integrated care approach could follow the ABC pathway: A) Appropriate antithrombotic therapy in all stroke/TIA patients in the acute phase as well as recommendations for the longer term treatment regimen are required to avoid recurrent stroke. B) For better functional and psychological status the assessment of post-stroke cognitive and physical impairment, depression, and anxiety as part of routine post-stroke work-up in every patient is necessary. C) Cardiovascular risk factors and comorbidities management further includes cardiovascular work-up, adapted drug therapy, but often also lifestyle changes that are central to the success of integrated care for stroke-heart syndrome. Greater patient and family/caregiver involvement in planning actions and the input and feedback on optimizing stroke care pathways is needed. Achieving integrated care is challenging and highly context dependent on different healthcare levels. A tailored approach will utilize a variety of enabling factors. In this narrative review, we summarize the current evidence and outline potential factors that will contribute to the successful implementation of integrated cardiovascular care for stroke-heart syndrome management.

Republished:Aspiration catheter failure leading to carotid-cavernous fistula during stroke thrombectomy

Endovascular thrombectomy in acute ischaemic stroke commonly uses aspiration catheters, either alone or in combination with stent retrievers. The Penumbra Aspiration System (Penumbra, Alameda, California, USA) was first approved by the US Food and Drug Administration in 2007, with low reported device-related complications. We present a case of a previously unreported complication related to malfunction of a Penumbra aspiration catheter during stroke thrombectomy resulting in a carotid-cavernous fistula.

Updates in mechanical thrombectomy

Stroke is a leading cause of morbidity and mortality. The advent of mechanical thrombectomy has largely improved patient outcomes. This article reviews the features and outcomes associated with aspiration, stent retrievers, and combination catheters used in current practice. There is also a discussion on clinical considerations based on anatomical features and clot composition. The reperfusion grading scale and outcome metrics commonly used following thrombectomy when a patient is still in the hospital are reviewed. Lastly, there are proposed discharge and outpatient follow-up goals in caring for patients hospitalized for a stroke.

Efficacy and safety of endovascular treatment in patients older than 90 with acute ischemic stroke: A retrospective cohort study

Background

Endovascular treatment (EVT) for acute ischemic stroke (AIS) with large vessel occlusion (LVO) is the standard of care treatment today. Although elderly patients comprise the majority of stroke patients, octogenarians and non-agenarians are often poorly represented or even excluded in clinical trials. We looked at the safety and efficacy of EVT for AIS with LVO in patients over 90 (Non-agenarians), in comparison to patients aged 80-89 (Octogenarians) and to patients younger than 80 years (<80yrs).

Methods

A retrospective analysis of patients who underwent EVT in a single stroke center during 2015-2019. Patients were divided into three subgroups based on their age: Non-agenarians, Octogenarians, and patients <80 yrs. The groups were compared based on baseline characteristics and stroke variables. In addition, we compared clinical and radiological outcomes including functional outcomes measured by the modified ranking scale (mRS) at day 90, symptomatic intracranial hemorrhage (sICH), and mortality.

Results

Three hundred and forty seven patients were included, 20 (5.7%) of them were non-agenarians, 96 (27.7%) were octogenarians and 231 (66.6%) were <80 yrs. No statistically significant differences were found between groups regarding baseline characteristics, cardiovascular risk factors, stroke variables, or successful revascularization rates. Puncture to recanalization time intervals showed an age-related non-significant increase between the groups with a median time of 67.8, 51.6, and 40.2 min of the non-agenarian, octogenarian, and <80 yrs groups, respectively (p-value = 0.3). Favorable outcome (mRS 0-2) was 15% in non-agenarians vs. 13.54% in octogenarians (p-value = 1) and 40.2% in <80 yrs. sICH occurred among 5% of non-agenarians, compared to 4% among octogenarians (p-value = 1) and 2.6% in <80 yrs. The mortality rate at 3 months was significantly higher (55%) in non-agenarians compared to octogenarians (28%) (p-value = 0.03) and to <80 yrs (19.48%).

Conclusion

EVT in nonagenarians demonstrated a high rate of successful revascularization, whilst also showing an increased rate of sICH when compared to octogenarians. Mortality rates showed an age-related correlation. Although further studies are needed to clarify the patient selection algorithm and identify sub-groups of elderly patients that could benefit from EVT, we showed that some patients do benefit from EVT therefore exclusion should not be based on age alone.

Upregulating HIF-1α to Boost the Survival of Neural Stem Cells via Functional Peptides-Complexed MRI-Visible Nanomedicine for Stroke Therapy

Neural stem cells (NSCs) transplantation has been considered as a promising strategy for the treatment of ischemic stroke. However, the therapeutic prospect is limited by the poor control over the survival, migration, and maturation of transplanted NSCs. Upregulating hypoxia inducible factor (HIF)-1α expression in stem cells can improve the survival and migration of NSCs grafted for stroke therapy. Functional peptide drugs, which could inhibit endogenous HIF-1α ubiquitination, might be used to effectively upregulate the HIF-1α expression in NSCs, thereby to improve the therapeutic effect in ischemia stroke. Herein, a magnetic resonance imaging (MRI)-visible nanomedicine is developed to codeliver functional peptides and superparamagnetic iron oxide (SPIO) nanoparticles into NSCs. This nanomedicine not only promotes the survival and migration ability of NSCs but also allows an in vivo tracking of transplanted NSCs with MRI. The results demonstrate the great potential of the functional peptides-complexed multifunctional nanomedicine in boosting the therapeutic effect of stem cell-based therapy in stroke.

Ginsenoside Rg1 Nanoparticles Induce Demethylation of H3K27me3 in VEGF-A and Jagged 1 Promoter Regions to Activate Angiogenesis After Ischemic Stroke

BACKGROUND

Compared with traditional drugs, nanomaterial drugs have the benefits of improving the solubility, bioavailability, and absorption rate of insoluble drugs. Nanoporous complexes can increase the efficiency with which drugs can penetrate the blood-brain barrier and reach target organs. Ginsenoside Rg1 is an effective drug that promotes angiogenesis. Ginsenoside Rg1 composite nanoparticles were employed to induce the expression of several key epigenetic enzymes and then activate the VEGF and Notch pathways after the onset of ischemic brain lesions.

METHODS

We constructed nanoparticles to fully encapsulate the therapeutic drug (ginsenoside Rg1), which can be transferred into brain tissue via the receptor-mediated transfer of drug-encapsulated nanoparticles. Evaluation of the therapeutic effect of ginsenoside Rg1 complex nanovesicles (CNV) was performed by in vitro and in vivo experiments. Real-time polymerase chain reaction (RT- PCR), Western blot, immunohistochemistry staining (IHC), and Co-immunoprecipitation (co-IP) were employed to screen for epigenetic enzymes with an up-regulated expression post ginsenoside Rg1-CNV intervention. RNA sequencing, shRNA knockdown, and chromatin Immunoprecipitation (ChIP) sequencing were performed to detect the target genes of ginsenoside Rg1-CNV that regulate angiogenesis. Then, bioinformatic analysis was performed to investigate the mechanism of action of epigenetic modifying enzymes in regulating target genes.

RESULTS

The average of the synthesized ginsenoside Rg1-CNV was 203.78±6.83 nm, the polydispersion index was 0.135±0.007, and the Zeta potential was 23.13±1.65 mV. Through in vivo and in vitro experiments, we found that it promotes the proliferation, migration, and tubular formation of brain microvascular endothelial cells (BMECs). Meanwhile, the intervention of ginsenoside Rg1-CNV promoted the demethylation of H3K27me3 within the promoter region of VEGF-A and Jagged1 genes and reduced the H3K27me3 modification within this region.

CONCLUSION

The ginsenoside Rg1 nanoparticles may be an available blood-brain barrier penetrating agent for ischemic stroke.

Clot Morphology in Acute Ischemic Stroke Decision Making

Stroke is a leading cause of death and disability in the world, and the provision of reperfusion therapy and endovascular therapy, in particular, have revolutionized the treatment of patients with stroke and opened opportunities to look at brain clots retrieved after the procedure. The use of histopathology and molecular profiling of clots is of growing research and clinical interest. However, its clinical implications and incorporation within stroke workflows remain suboptimal. Recent studies have indicated that the study of brain clots may inform the mechanism of stroke and hence guide treatment decision-making in select groups of patients, especially patients without a defined cause or known mechanism. This article provides a comprehensive overview of various clot histopathological examinations in acute stroke-care settings, their clinical utility, and existing gaps and opportunities for further research. We also provide targeted recommendations to improve clot analysis workflow, hence standardizing its incorporation into clinical practice.

Ischemic Stroke, Lessons from the Past towards Effective Preclinical Models

Ischemic stroke is a leading cause of death worldwide, mainly in western countries. So far, approved therapies rely on reperfusion of the affected brain area, by intravenous thrombolysis or mechanical thrombectomy. The last approach constitutes a breakthrough in the field, by extending the therapeutic window to 16-24 h after stroke onset and reducing stroke mortality. The combination of pharmacological brain-protective strategies with reperfusion is the future of stroke therapy, aiming to reduce brain cell death and decrease patients' disabilities. Recently, a brain-protective drug-nerinetide-reduced brain infarct and stroke mortality, and improved patients' functional outcomes in clinical trials. The success of new therapies relies on bringing preclinical studies and clinical practice close together, by including a functional outcome assessment similar to clinical reality. In this review, we focused on recent upgrades of in vitro and in vivo stroke models for more accurate and effective evaluation of therapeutic strategies: from spheroids to organoids, in vitro models that include all brain cell types and allow high throughput drug screening, to advancements in in vivo preclinical mouse stroke models to mimic the clinical reality in surgical procedures, postsurgical care, and functional assessment.

Association of Thrombectomy With Functional Outcome for Patients With Ischemic Stroke Who Presented in the Extended Time Window With Extensive Signs of Infarction

IMPORTANCE

Only limited data are available about a potential benefit associated with endovascular treatment (EVT) for patients with ischemic stroke presenting in the extended time window who also show signs of extensive infarction.

OBJECTIVE

To assess the association of recanalization after EVT with functional outcomes for patients with ischemic stroke presenting in the extended time window who also show signs of extensive infarction.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective, multicenter cohort study included patients enrolled in the German Stroke Registry-Endovascular Treatment with an Alberta Stroke Program Early CT Score (ASPECTS) of 5 or less who presented between 6 and 24 hours after stroke onset and underwent computed tomography and subsequent EVT between July 1, 2015, and December 31, 2019.

MAIN OUTCOMES AND MEASURES

The primary end point was a modified Rankin Scale (mRS) score of 3 or less at day 90. The association between recanalization (defined as the occurrence of a modified Thrombolysis in Cerebral Infarction Scale score of 2b or 3) and outcome was assessed using logistic regression and inverse probability weighting analysis.

INTERVENTION

Endovascular treatment.

RESULTS

Of 5853 patients, 285 (5%; 146 men [51%]; median age, 73 years [IQR, 62-81 years]) met the inclusion criteria and were analyzed. Of these 285 patients, 79 (27.7%) had an mRS score of 3 or less at day 90. The rate of successful recanalization was 75% (215 of 285) and was independently associated with a higher probability of reaching an mRS score of 3 or less (adjusted odds ratio, 4.39; 95% CI, 1.79-10.72; P < .001). In inverse probability weighting analysis, a modified Thrombolysis in Cerebral Infarction Scale score of 2b or 3 was associated with a 19% increase (95% CI, 9%-29%; P < .001) in the probability for an mRS score of 3 or more. Multivariable logistic regression analysis suggested a significant treatment benefit associated with vessel recanalization in a time window of up to 17.6 hours and ASPECTS of 3 to 5. The rate of secondary symptomatic intracerebral hemorrhage was 6.3% (18 of 285).

CONCLUSIONS AND RELEVANCE

In this cohort study reflecting daily clinical practice, vessel recanalization for patients with a low ASPECTS and extended time window was associated with better functional outcomes in a time window up to 17.6 hours and ASPECTS of 3 to 5. The results of this study encourage current randomized clinical trials to enroll patients with a low ASPECTS, even within the extended time window.

Efficacy of Balloon Guide Catheter-Assisted Thrombus Repair in Stroke Treatment: A Retrospective Survey in China

Background

The first-pass (FP) effect, defined by successful cerebral reperfusion from a single pass of an endovascular stentriever, was associated with shorter procedural times and possible improved outcomes in patients with ischemic stroke secondary to large vessel occlusion. The adjunctive use of balloon guide catheter (BGC) may increase the rates of the first-pass effect. In this retrospective study we examined the impact of BGC on the first-pass effect in acute stroke patients.

Methods

We included patients with acute ischemic stroke with large vessel occlusion treated by endovascular thrombectomy from 2018 to 2019. We categorized the cases into BGC and non-BGC groups. Differences in time metrics and outcomes were compared.

Result

One hundred and thirty-two patients were included, and sixty-two were in BGC group (47.0%). The median procedural time was shorter (83.0 minutes vs 120.0 minutes, P = 0.000), and FP rate was higher in BGC group (58.1% vs 32.9%, P = 0.004) compared with non-BGC group. Proportion of modified Thrombolysis in Cerebral Infarction (mMTICI) 3 was higher (66.1% vs 37.1%, P = 0.001), and modified Rankin Scale (mRS) 0 to 2 was higher (59.7% vs 41.4%, P = 0.036) in BGC group compared with non-BGC group. In addition, BGC was associated with successful reperfusion odds ratio, 0.383; 95% confidence interval: 0.174-0.847; P = 0.018). The FP rate of BGC in the distal ICA was higher than that in the proximal ICA (87.5% vs 39.5%, P = 0.000), and the good clinical outcome rate at 90 days in the distal ICA was also higher than that in the proximal ICA (91.7% vs 39.5%, P = 0.000).

Conclusion

We showed that BGC shortened the procedural time and increased the rate of the successful FP. We recommend that BGC could be considered the preferred technique for endovascular intervention in stroke.

Investigation into the potential mechanism and molecular targets of Fufang Xueshuantong capsule for the treatment of ischemic stroke based on network pharmacology and molecular docking

Fufang Xueshuantong (FFXST) capsule is a traditional Chinese medicine (TCM) preparation used to activate blood circulation, resolve stasis, benefit qi, and nourish yin in clinical practice. However, its potential mechanism and molecular targets after ischemic stroke (IS) have not been investigated. The aim of this research was to investigate the molecular mechanisms of FFXST in the treatment of IS based on network pharmacology and molecular docking. We used the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP) to collect candidate compounds of four herbs in FFXST; disease-related differential genes were screened using the Gene Expression Omnibus (GEO) database, and a compound–disease network was created using Cytoscape 3.8.2 software. The topological analysis of the protein–protein interaction (PPI) network was then created to determine the candidate targets of FFXST against IS. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were conducted using the clusterProfiler package in R. The gene–pathway network of FFXST against IS was created to obtain the key target genes. Molecular docking was used to validate the core targets using AutoDock Vina 1.1.2. A total of 455 candidate compounds of FFXST and 18,544 disease-related differential genes were screened. Among them, FFXST targets for IS treatment had 67 active compounds and 10 targets in the PPI network related to STAT1, STAT3, and HIF1A. The biological processes of GO analysis included the regulation of reactive oxygen species metabolic process, cellular response to chemical stress, regulation of angiogenesis, regulation of vasculature development, positive regulation of cytokine production, and response to oxidative stress. The KEGG enrichment analysis showed that Kaposi sarcoma-associated herpesvirus infection, microRNAs in the cancer signaling pathway, Th17 cell differentiation, and HIF-1 signaling pathway were significantly enriched. The network pharmacology outcomes were further verified by molecular docking. We demonstrated that FFXST protection against IS may relate to the regulation of oxidative stress, immune inflammatory response, and angiogenesis through the relevant signaling pathways. Our study systematically illustrated the application of network pharmacology and molecular docking in evaluating characteristics of multi-component, multi-target, and multi-pathway of FFXST for IS.

Outcome of Endovascular Thrombectomy in Pre-stroke Dependent Patients With Acute Ischemic Stroke: A Systematic Review and Meta-Analysis

Introduction

Endovascular thrombectomy (EVT) is a well-established and effective therapeutic option for patients that meet certain criteria. However, this modality is not well studied in patients with pre-existing disability. The aim of the present study was to investigate the impact of mechanical thrombectomy in patients with acute onset ischemic stroke and pre-stroke dependency (PSD) in regard to their clinical outcome and mortality.

Materials and Methods

The MEDLINE, Scopus, and Cochrane Library databases were comprehensively searched with a cut-off date of December 11th, 2021. We performed meta-analysis to investigate the 90-day clinical outcome, the 90-day mortality, and the rate of symptomatic intracerebral hemorrhage (sICH) between the PSD (modified Rankin Scale score ≥ 3) and non-PSD (modified Rankin Scale score = 0-2) groups who underwent EVT for acute onset ischemic stroke.

Results

Six studies were included in the meta-analysis involving 4,543 cases with no PSD and 591 cases with PSD. The non-PSD group showed a statistically significant better clinical outcome at 90 days compared to the PSD group [RR (95% CI) = 1.44 (1.06, 1.85); p z = 0.02]. The non-PSD group demonstrated a statistically significant lower risk of death at 90 days in comparison to the PSD group [RR (95% CI) = 0.45 (0.41, 0.50); p z < 0.01]. Lastly, the rate of sICH was comparable between the two groups [RR (95% CI) = 0.89 (0.64, 1.24); p z = 0.48].

Discussion

We report a higher rate of unfavorable clinical outcome and a higher mortality rate in patients with PSD undergoing EVT compared to those with no previous disability. However, there was a significant proportion of PSD cases who fared well post-procedurally, indicating that PSD patients should not be routinely excluded from mechanical thrombectomy.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021284181, identifier: CRD42021284181.

TCD hemodynamics findings in the subacute phase of anterior circulation stroke patients treated with mechanical thrombectomy

Despite mechanical thrombectomy, the prognosis for many patients with anterior circulation ischemic stroke (ACIS) remains poor. This retrospective study reports consecutive mechanical thrombectomy procedures for ACIS at our hospital over 4 years. Hemodynamics were explored using transcranial Doppler ultrasound. The functional outcome was assessed using the modified Rankin scale. A total of 121 eligible cases were included: 61 (50.4%) exhibited good outcomes (modified Rankin scale score ≤2) by day 90. The logistic regression analysis showed that ipsilateral middle cerebral artery (iMCA) systolic blood flow (SBF) (OR = 0.983, 95% CI: 0.969–0.997, P = 0.014), preoperative National Institutes of Health Stroke Scale (NIHSS)score (OR = 1.160, 95% CI: 1.067–1.261, P < 0.001), intracranial hemorrhage after therapy (OR = 19.514, 95% CI: 4.364–87.265, P < 0.001), and Alberta Stroke Program Early Computed Tomography Score (OR = 0.639, 95% CI: 0.416–0.981, P = 0.040) were independently associated with prognosis. The iMCA SBF and preoperative NIHSS score were significantly predictive of a good outcome in the receiver operating characteristic analysis. In conclusion, elevated iMCA SBF might be a prognostic indicator of a good 90-day outcome following endovascular treatment in ACIS patients treated with mechanical thrombectomy, but large prospective studies are mandatory to validate the findings of our study.

Rapid Identification of Patients Eligible for Direct Emergent Computed Tomography Angiography during Acute Ischemic Stroke: The DARE-PACE Assessment

Background: We investigated the clinical signs to establish a method for rapid identification of patients with the National Institute of Health Stroke Scale (NIHSS) score ≥ 8 eligible for direct brain CTA study; Methods: We retrospectively enrolled 2895 in patients with acute ischemic stroke (AIS). Four items in the NIHSS were selected as the main clinical signs of stroke; Results: A total of 922 (31.8%) patients had an initial NIHSS score of ≥8. The average door-to-CT time and door-to-CTA time were 13.4 ± 1.8 and 75.5 ± 44.5 min, respectively. Among 658 patients who had the priority signs, namely dense hemiplegia (D), aphasia with right arm drop (AR), and eyeball forced deviation (E), 634 patients (96.4%) with an NIHSS score ≥ 8 were identified. By using a classification and regression tree analysis, 153 patients with an NIHSS ≥ 8 were identified among 175 patients (87.4%) who had the secondary signs, namely hemiparesis with limb falls (P), aphasia (A), drowsy or worse consciousness (C), and eyeball limitation (E). The sensitivity, specificity, and accuracy were 85.4%, 97.7%, and 95.3%, respectively. Conclusions: The DARE-PACE assessment involving a checkbox list provides excellent accuracy for rapid identification of AIS patients with an NIHSS score ≥ 8 for direct CTA study to reduce the time delay for endovascular thrombectomy.

OUP accepted manuscript

The management of patients with stroke is often multidisciplinary, involving various specialties and healthcare professionals. Given the common shared risk factors for stroke and cardiovascular disease, input may also be required from the cardiovascular teams, as well as patient caregivers and next-of-kin. Ultimately, the patient is central to all this, requiring a coordinated and uniform approach to the priorities of post-stroke management, which can be consistently implemented by different multidisciplinary healthcare professionals, as part of the patient ‘journey’ or ‘patient pathway,’ supported by appropriate education and tele-medicine approaches. All these aspects would ultimately aid delivery of care and improve patient (and caregiver) engagement and empowerment. Given the need to address the multidisciplinary approach to holistic or integrated care of patients with heart disease and stroke, the European Society of Cardiology Council on Stroke convened a Task Force, with the remit to propose a consensus on Integrated care management for optimizing the management of stroke and associated heart disease. The present position paper summarizes the available evidence and proposes consensus statements that may help to define evidence gaps and simple practical approaches to assist in everyday clinical practice. A post-stroke ABC pathway is proposed, as a more holistic approach to integrated stroke care, would include three pillars of management:

A: Appropriate Antithrombotic therapy.

B: Better functional and psychological status.

C: Cardiovascular risk factors and Comorbidity optimization (including lifestyle changes).

Presence of Thrombectomy-capable Stroke Centers Within Hospital Service Areas Explains Regional Variation in the Case Fatality Rate of Acute Ischemic Stroke in Korea

OBJECTIVES

This study aimed to explore the status of regional variations in acute ischemic stroke (AIS) treatment and investigate the association between the presence of a thrombectomy-capable stroke center (TSC) and the case fatality rate (CFR) of AIS within hospital service areas (HSAs).

METHODS

This observational cross-sectional study analyzed acute stroke quality assessment program data from 262 hospitals between 2013 and 2016. TSCs were defined according to the criteria of the Joint Commission. In total, 64 HSAs were identified based on the addresses of hospitals. We analyzed the effects of structure factors, process factors, and the presence of a TSC on the CFR of AIS using multivariate logistic regression.

RESULTS

Among 262 hospitals, 31 hospitals met the definition of a TSC. Of the 64 HSAs, only 20 had a TSC. At hospitals, the presence of a stroke unit, the presence of stroke specialists, and the rate of endovascular thrombectomy (EVT) treatment were associated with reductions in the CFR. In HSAs, the rate of EVT treatment (odds ratio [OR], 0.98; 95% confidence interval [CI], 0.97 to 0.99) and the presence of a TSC (OR, 0.93; 95% CI, 0.88 to 0.99) significantly reduced the CFR of AIS.

CONCLUSIONS

The presence of a TSC within an HSA, corresponding to structure and process factors related to the quality of care, contributed significantly to lowering the CFR of AIS. The CFR also declined as the rate of treatment increased. This study highlights the importance of TSCs in the development of an acute stroke care system in Korea.

Importance of computed tomography angiography in acute/hyperacute ischemic stroke

Objective

To evaluate the importance of computed tomography and computed tomography angiography (CTA) in stroke protocols, as well as their impact on endovascular treatment and on the determination of the etiology.

Materials and Methods

Were evaluated 28 patients with acute/hyperacute stroke in the anterior circulation who underwent intracranial and cervical CTA between April 2018 and August 2019. The parameters evaluated were the degree of stenosis, plaque characteristics, type of infarct, treatment, etiology, and the Alberta Stroke Program Early CT Score (ASPECTS).

Results

Of the 28 patients evaluated, 16 (57.1%) had an ASPECTS of 10 (the maximum score, indicative of normality). Four patients (14.3%) underwent thrombolytic treatment, and seven (25.0%) underwent mechanical thrombectomy. The etiology was atherosclerosis in 32.1% of the patients, cerebral small-vessel disease in 7.1%, cardioembolic in 7.1%, and undetermined in 53.6%. Regarding plaque, 17.9% of the patients presented stenosis ≥ 50%, 21.4% presented stable plaques, and 42.9% presented vulnerable plaques. Patients with a lower ASPECTS were more likely to have relevant stenosis and were more likely to have a total infarct.

Conclusion

In the evaluation of patients with acute/hyperacute strokes, CTA provides important information, identifying occlusion, as well as helping define the etiology and inform decisions regarding treatment.

TAB-TICI Score: Successful Recanalization Score After Endovascular Thrombectomy in Acute Stroke

Background and Purpose: Successful reperfusion therapy is supposed to be comprehensive and validated beyond the grade of recanalization. This study aimed to develop a novel scoring system for defining the successful recanalization after endovascular thrombectomy.

Methods: We analyzed the data of consecutive acute stroke patients who were eligible to undergo reperfusion therapy within 24 h of onset and who underwent mechanical thrombectomy using a nationwide multicenter stroke registry. A new score was produced using the predictors which were directly linked to the procedure to evaluate the performance of the thrombectomy procedure.

Results: In total, 446 patients in the training population and 222 patients in the validation population were analyzed. From the potential components of the score, four items were selected: Emergency Room-to-puncture time (T), adjuvant devices used (A), procedural intracranial bleeding (B), and post-thrombectomy reperfusion status [Thrombolysis in Cerebral Infarction (TICI)]. Using these items, the TAB-TICI score was developed, which showed good performance in terms of discriminating early neurological aggravation [AUC 0.73, 95% confidence interval (CI) 0.67–0.78, P < 0.01] and favorable outcomes (AUC 0.69, 95% CI 0.64–0.75, P < 0.01) in the training population. The stability of the TAB-TICI score was confirmed by external validation and sensitivity analyses. The TAB-TICI score and its derived grade of successful recanalization were significantly associated with the volume of thrombectomy cases at each site and in each admission year.

Conclusion: The TAB-TICI score is a valid and easy-to-use tool to more comprehensively define successful recanalization after endovascular thrombectomy in acute stroke patients with large vessel occlusion.

Alphabetical Mnemonic to Assist in the Treatment of an Acute Ischemic Stroke

Determining the treatment plan and how to successfully manage a patient suffering from an acute ischemic stroke can be challenging for a registered nurse (RN) in the emergency department. Using a mnemonic in the treatment process assists in reducing medical errors and increases the likelihood of making positive clinical outcomes. Mnemonics sum up complex strategies into relevant information that can be comprehensible for users. The authors have created a mnemonic strategy to provide RNs in the emergency department with a structured approach to the pharmacotherapeutic strategies used in treating patients with an acute ischemic stroke. All guidelines used throughout the article are in concurrence.

Thrombectomy in Extensive Stroke May Not Be Beneficial and Is Associated With Increased Risk for Hemorrhage

Background and Purpose

This study evaluates the benefit of endovascular treatment (EVT) for patients with extensive baseline stroke compared with best medical treatment.

Methods

This retrospective, multicenter study compares EVT and best medical treatment for computed tomography (CT)–based selection of patients with extensive baseline infarcts (Alberta Stroke Program Early CT Score ≤5) attributed to anterior circulation stroke. Patients were selected from the German Stroke Registry and 3 tertiary stroke centers. Primary functional end points were rates of good (modified Rankin Scale score of ≤3) and very poor outcome (modified Rankin Scale score of ≥5) at 90 days. Secondary safety end point was the occurrence of symptomatic intracerebral hemorrhage. Angiographic outcome was evaluated with the modified Thrombolysis in Cerebral Infarction Scale.

Results

After 1:1 pair matching, a total of 248 patients were compared by treatment arm. Good functional outcome was observed in 27.4% in the EVT group, and in 25% in the best medical treatment group (P=0.665). Advanced age (adjusted odds ratio, 1.08 [95% CI, 1.05–1.10], P<0.001) and symptomatic intracerebral hemorrhage (adjusted odds ratio, 6.35 [95% CI, 2.08–19.35], P<0.001) were independently associated with very poor outcome. Mortality (43.5% versus 28.9%, P=0.025) and symptomatic intracerebral hemorrhage (16.1% versus 5.6%, P=0.008) were significantly higher in the EVT group. The lowest rates of good functional outcome (≈15%) were observed in groups of failed and partial recanalization (modified Thrombolysis in Cerebral Infarction Scale score of 0/1–2a), whereas patients with complete recanalization (modified Thrombolysis in Cerebral Infarction Scale score of 3) with recanalization attempts ≤2 benefitted the most (modified Rankin Scale score of ≤3:42.3%, P=0.074) compared with best medical treatment.

Conclusions

In daily clinical practice, EVT for CT–based selected patients with low Alberta Stroke Program Early CT Score anterior circulation stroke may not be beneficial and is associated with increased risk for hemorrhage and mortality, especially in the elderly. However, first- or second-pass complete recanalization seems to reveal a clinical benefit of EVT highlighting the vulnerability of the low Alberta Stroke Program Early CT Score subgroup.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03356392.

Staged strategy using a transcarotid approach for acute tandem occlusions with left common carotid artery origin steno-occlusive lesion

Background:

Endovascular treatment for acute tandem occlusion (ATO) of the combination of an ipsilateral extracranial internal carotid artery (ICA) steno-occlusive lesion with concurrent intracranial artery occlusion is challenging. Whether extracranial lesions, especially in cases of the left common carotid artery (LCCA) origin steno-occlusive lesions, should be treated after recanalization of an occluded intracranial artery by mechanical thrombectomy simultaneously in the same session has not been established. We report two cases of successful ATO with LCCA origin steno-occlusive lesions treated by staged retrograde transcarotid LCCA stenting followed emergent mechanical thrombectomy in two sessions because of the tortuous aortic arch.

Case Description:

A 61-year-old man with left ICA occlusion and an 82-year-old woman with left middle cerebral artery occlusion underwent emergent mechanical thrombectomy for ATO with LCCA origin stenoocclusive lesions. We achieved recanalization of large vessels, but severe stenosis of LCCAs remained. Because of the tortuous aortic arch, we decided to treat LCCA origin steno-occlusive lesions with staged stenting in the other session followed emergent mechanical thrombectomy. Postoperative courses were uneventful, and their symptoms improved. We performed stenting using a transcarotid approach through CCA cut down for LCCA steno-occlusive lesions without any complications.

Conclusion:

The staged strategy leaving LCCA origin stenosis seems to offer a better strategy than the simultaneous strategy for ATO with LCCA origin steno-occlusive lesions. A retrograde transcarotid approach through CCA cut down is recommended for LCCA stenting.

Use of a Smartphone Application to Speed Up Interhospital Transfer of Acute Ischemic Stroke Patients for Thrombectomy

Background: In most countries, large cerebral artery occlusion is identified as the leading cause of disability. In 2015, five large-scale clinical trials confirmed the benefit of intra-arterial thrombectomy. However, thrombectomy is a highly technical and facility-dependent procedure. Primary stroke centers need to transfer patients to comprehensive stroke centers to perform thrombectomy. The time-lapse during interhospital transfer would decrease the chance of the patient's proper recovery. Communication barriers also contribute to this delay.

Aims: We used a smartphone application to overcome communication barriers between hospitals. We aimed to shorten the door-to-puncture time of interhospital transfer patients.

Methods: We began using a smartphone application, “LINE,” to facilitate interhospital communication on May 01, 2018. We carried out retrospective data analyses for all the transfer patients (n = 351), with the primary outcome being the door-to-puncture time in our comprehensive stroke center (China Medical University Hospital). We compared the three periods: May 01 to Dec 31, 2017 (before the use of the smartphone application); May 01 to Dec 31, 2018 (the 1st year of using the smartphone application); and May 01 to Dec 31, 2019 (the 2nd year of using the smartphone application). We also compared the transfer data with non-transfer thrombectomies in the same period.

Results: We compared 2017, 2018, and 2019 data. The total number of transfer patients increased over the years: 63, 113, 175, respectively. The mean door-to-puncture time decreased significantly, going from 109, through 102, to 92 min. Meanwhile, the mean door-to-puncture time in non-transfer patients were 140.3, 122.1, and 129.3 min. The main reason of time saving was the change of the way of communication, from point-to-point interhospital communication to hub-to-spoke interhospital communication.

Conclusions: We used this smartphone application to enhance interhospital communication, changed from the point-to-point to hub-to-spoke method. It made us overcome the communication barrier and build up interhospital connection, thus shortening the door-to-puncture time. Our experience demonstrated the importance of close communication and teamwork in hyperacute stroke care, especially in interhospital transfer for thrombectomy.

Therapeutic Nanoparticles for the Different Phases of Ischemic Stroke

Stroke represents the second leading cause of mortality and morbidity worldwide. Ischemic strokes are the most prevalent type of stroke, and they are characterized by a series of pathological events prompted by an arterial occlusion that leads to a heterogeneous pathophysiological response through different hemodynamic phases, namely the hyperacute, acute, subacute, and chronic phases. Stroke treatment is highly reliant on recanalization therapies, which are limited to only a subset of patients due to their narrow therapeutic window; hence, there is a huge need for new stroke treatments. Nonetheless, the vast majority of promising treatments are not effective in the clinical setting due to their inability to cross the blood-brain barrier and reach the brain. In this context, nanotechnology-based approaches such as nanoparticle drug delivery emerge as the most promising option. In this review, we will discuss the current status of nanotechnology in the setting of stroke, focusing on the diverse available nanoparticle approaches targeted to the different pathological and physiological repair mechanisms involved in each of the stroke phases.

Serum Levels of Soluble Triggering Receptor Expressed on Myeloid Cells-1 Associated with the Severity and Outcome of Acute Ischemic Stroke

Stroke is a neurological emergency, where the mechanism of the blood supply to the brain is impaired, resulting in brain cell ischemia and death. Neuroinflammation is a key component in the ischemic cascade that results in cell damage and death after cerebral ischemia. The triggering receptor expressed on myeloid cells-1 (TREM-1) modulates neuroinflammation after acute ischemic stroke. In the present study, 60 patients with acute ischemic stroke, who had been subjected to neurological examinations and National Institutes of Health Stroke Scale (NIHSS) and brain magnetic resonance imaging studies, were enrolled in the emergency room of Kaohsiung Chang Gung Memorial Hospital. Twenty-four healthy volunteers were recruited as controls. The serum levels of soluble TREM-1 (sTREM-1), human S100 calcium-binding protein B (S100B), and proinflammatory cytokines and chemokines, including tumor necrosis α (TNF-α), interleukin 1β, interleukin 6 (IL-6), interleukin 8, and interferon-γ were measured immediately after acute ischemic stroke. The serum levels of sTREM-1, TNFα, IL-6, and S100B were correlated with the stroke volume and NIHSS, after acute ischemic stroke. Additionally, the serum levels of sTREM-1 were significantly positively correlated with S100B. The functional outcomes were evaluated 6 months after ischemic stroke by the Barthel index, which was correlated with the age and levels of sTREM-1 and S100B. We suggest that acute ischemic stroke induces neuroinflammation by the activation of the TREM-1 signaling pathway and the downstream inflammatory machinery that modulates the inflammatory response and ischemic neuronal cell death. From a translational perspective, our results may allow for the development of a new therapeutic strategy for acute ischemic stroke by targeting the TREM-1 signaling pathway.

Aspiration catheter failure leading to carotid-cavernous fistula during stroke thrombectomy

Endovascular thrombectomy in acute ischaemic stroke commonly uses aspiration catheters, either alone or in combination with stent retrievers. The Penumbra Aspiration System (Penumbra, Alameda, California, USA) was first approved by the US Food and Drug Administration in 2007, with low reported device-related complications. We present a case of a previously unreported complication related to malfunction of a Penumbra aspiration catheter during stroke thrombectomy resulting in a carotid-cavernous fistula.

Multimodal Predictive Modeling of Endovascular Treatment Outcome for Acute Ischemic Stroke Using Machine-Learning

Background and Purpose:

This study assessed the predictive performance and relative importance of clinical, multimodal imaging, and angiographic characteristics for predicting the clinical outcome of endovascular treatment for acute ischemic stroke.

Methods:

A consecutive series of 246 patients with acute ischemic stroke and large vessel occlusion in the anterior circulation who underwent endovascular treatment between April 2014 and January 2018 was analyzed. Clinical, conventional imaging (electronic Alberta Stroke Program Early CT Score, acute ischemic volume, site of vessel occlusion, and collateral score), and advanced imaging characteristics (CT-perfusion with quantification of ischemic penumbra and infarct core volumes) before treatment as well as angiographic (interval groin puncture-recanalization, modified Thrombolysis in Cerebral Infarction score) and postinterventional clinical (National Institutes of Health Stroke Scale score after 24 hours) and imaging characteristics (electronic Alberta Stroke Program Early CT Score, final infarction volume after 18–36 hours) were assessed. The modified Rankin Scale (mRS) score at 90 days (mRS-90) was used to measure patient outcome (favorable outcome: mRS-90 ≤2 versus unfavorable outcome: mRS-90 >2). Machine-learning with gradient boosting classifiers was used to assess the performance and relative importance of the extracted characteristics for predicting mRS-90.

Results:

Baseline clinical and conventional imaging characteristics predicted mRS-90 with an area under the receiver operating characteristics curve of 0.740 (95% CI, 0.733–0.747) and an accuracy of 0.711 (95% CI, 0.705–0.717). Advanced imaging with CT-perfusion did not improved the predictive performance (area under the receiver operating characteristics curve, 0.747 [95% CI, 0.740–0.755]; accuracy, 0.720 [95% CI, 0.714–0.727]; P =0.150). Further inclusion of angiographic and postinterventional characteristics significantly improved the predictive performance (area under the receiver operating characteristics curve, 0.856 [95% CI, 0.850–0.861]; accuracy, 0.804 [95% CI, 0.799–0.810]; P <0.001). The most important parameters for predicting mRS 90 were National Institutes of Health Stroke Scale score after 24 hours (importance =100%), premorbid mRS score (importance =44%) and final infarction volume on postinterventional CT after 18 to 36 hours (importance =32%).

Conclusions:

Integrative assessment of clinical, multimodal imaging, and angiographic characteristics with machine-learning allowed to accurately predict the clinical outcome following endovascular treatment for acute ischemic stroke. Thereby, premorbid mRS was the most important clinical predictor for mRS-90, and the final infarction volume was the most important imaging predictor, while the extent of hemodynamic impairment on CT-perfusion before treatment had limited importance.

Computed tomography-based triage of extensive baseline infarction: ASPECTS and collaterals versus perfusion imaging for outcome prediction

BACKGROUND

Patients presenting with large baseline infarctions are often excluded from mechanical thrombectomy (MT) due to uncertainty surrounding its effect on outcome. We hypothesized that computed tomography perfusion (CTP)-based selection may be predictive of functional outcome in low Alberta Stroke Program Early CT Score (ASPECTS) patients.

METHODS

This was a double-center, retrospective analysis of patients presenting with ASPECTS≤5 who received multimodal admission CT imaging between May 2015 and June 2020. The predicted ischemic core (pCore) was defined as a reduction in cerebral blood flow (rCBF), while mismatch volume was defined using time to maximum (Tmax). The pCore perfusion mismatch ratio (CPMR) was also calculated. These parameters (pCore, mismatch volume, and CPMR), as well as a combined radiological score consisting of ASPECTS and collateral status (ASCO score), were tested in logistic regression and receiver operating characteristic (ROC) analyses. The primary outcome was favorable modified Rankin Scale (mRS) at discharge (≤3).

RESULTS

A total of 113 patients met the inclusion criteria. The median ischemic core volume was 74.1 mL (IQR 43.8-121.8). The ASCO score was associated with favorable outcome at discharge (aOR 3.7, 95% CI 1.8 to 10.7, P=0.002), while no association was observed for the CTP parameters. A model including the ASCO score also had significantly higher area under the curve (AUC) values compared with the CTP-based model (0.88 vs 0.64, P=0.018).

CONCLUSIONS

The ASCO score was superior to the CTP-based model for the prediction of good functional outcome and could represent a quick, practical, and easily implemented method for the selection of low ASPECTS patients most likely benefit from MT.

Real-World Comparison of Human and Software Image Assessment in Acute Ischemic Stroke Patients' Qualification for Reperfusion Treatment

Our aim was to compare human and computer accuracy in reading medical images of acute stroke patients. We analyzed data of patients who underwent assessment of Alberta Stroke Program Early CT Score (ASPECTS) and CT Perfusion (CTP) via Rapid Processing of Perfusion and Diffusion (RAPID) software RAPID ASPECTS, and RAPID CTP), compared to radiologist reports and manual measurements. We compared volumes calculated by RAPID CTP software with those selected by scanner-equipped software (GE). For reference, follow-up images were manually assessed in accordance with the Alberta Stroke Program Early CT Score (ASPECTS) territories retrospectively. Although exact ASPECTS score agreement between the automatic and manual methods, and between each method and follow-up, was poor, crossing of the threshold for reperfusion therapy was characterized by an 80% match. CT perfusion analyses yielded only slight agreement (kappa = 0.193) in the qualification of patients for therapy. Either automatic or manual scoring methods of non-contrast images imply similar clinical decisions in real-world circumstances. However, volume measurements performed by fully automatic and manually assisted systems are not comparable. Thresholds devised and validated for computer algorithms are not compatible with measurements performed manually using other software and should not be applied to setups other than those with which they were developed.

Three-dimensional regions-of-interest-based intra-operative four-dimensional soft tissue perfusion imaging using a standard x-ray system with no gantry rotation: A simulation study for a proof of concept

PURPOSE

Many interventional procedures aim at changing soft tissue perfusion or blood flow. One problem at present is that soft tissue perfusion and its changes cannot be assessed in an interventional suite because cone-beam computed tomography is too slow (it takes 4-10 s per volume scan). In order to address the problem, we propose a novel method called IPEN for Intra-operative four-dimensional soft tissue PErfusion using a standard x-ray system with No gantry rotation.

METHODS

IPEN uses two input datasets: (a) the contours and locations of three-dimensional regions-of-interest (ROIs) such as arteries and sub-sections of cancerous lesions, and (b) a series of x-ray projection data obtained from an intra-arterial contrast injection to contrast enhancement to wash-out. IPEN then estimates a time-enhancement curve (TEC) for each ROI directly from projections without reconstructing cross-sectional images by maximizing the agreement between synthesized and measured projections with a temporal roughness penalty. When path lengths through ROIs are known for each x-ray beam, the ROI-specific enhancement can be accurately estimated from projections. Computer simulations are performed to assess the performance of the IPEN algorithm. Intra-arterial contrast-enhanced liver scans over 25 s were simulated using XCAT phantom version 2.0 with heterogeneous tissue textures and cancerous lesions. The following four sub-studies were performed: (a) The accuracy of the estimated TECs with overlapped lesions was evaluated at various noise (dose) levels with either homogeneous or heterogeneous lesion enhancement patterns; (b) the accuracy of IPEN with inaccurate ROI contours was assessed; (c) we investigated how overlapping ROIs and noise in projections affected the accuracy of the IPEN algorithm; and (d) the accuracy of the perfusion indices was assessed.

RESULTS

The TECs estimated by IPEN were sufficiently accurate at a reference dose level with the root-mean-square deviation (RMSD) of 0.0027 ± 0.0001 cm^-1 or 13 ± 1 Hounsfield unit (mean ± standard deviation) for the homogeneous lesion enhancement and 0.0032 ± 0.0005 cm^-1 for the heterogeneous enhancement (N = 20 each). The accuracy was degraded with decreasing doses: The RMSD with homogeneous enhancement was 0.0220 ± 0.0003 cm^-1 for 20% of the reference dose level. Performing 3 × 3 pixel averaging on projection data improved the RMSDs to 0.0051 ± 0.0002 cm^-1 for 20% dose. When the ROI contours were inaccurate, smaller ROI contours resulted in positive biases in TECs, whereas larger ROI contours produced negative biases. The bias remained small, within ± 0.0070 cm^-1 , when the Sorenson-Dice coefficients (SDCs) were larger than 0.81. The RMSD of the TEC estimation was strongly associated with the condition of the problem, which can be empirically quantified using the condition number of a matrix A z that maps a vector of ROI enhancement values z to projection data and a weighted variance of projection data: a linear correlation coefficient (R) was 0.794 (P < 0.001). The perfusion index values computed from the estimated TECs agreed well with the true values (R ≥ 0.985, P < 0.0001).

CONCLUSION

The IPEN algorithm can estimate ROI-specific TECs with high accuracy especially when 3 × 3 pixel averaging is applied, even when lesion enhancement is heterogeneous, or ROI contours are inaccurate but the SDC is at least 0.81.

Liquid biopsy markers for stroke diagnosis

INTRODUCTION

There is a short time window (4.5 h) for the effective treatment of acute ischemic stroke (AIS), which uses recombinant tissue plasminogen activator (rt-PA). Unfortunately, this short therapeutic timeframe is a contributing factor to the relatively small number of patients (~7%) that receive rt-PA. While neuroimaging is the major diagnostic for AIS, more timely decisions could be made using a molecular diagnostic.

AREAS COVERED

In this review, we survey neuroimaging techniques used to diagnose stroke and their limitations. We also highlight the potential of various molecular/cellular biomarkers, especially peripheral blood-based (i.e. liquid biopsy) biomarkers, for diagnosing stroke to allow for precision decisions on managing stroke in a timely manner. Both protein and nucleic acid molecular biomarkers are reviewed. In particular, mRNA markers are discussed for AIS and hemorrhagic stroke diagnosis sourced from both cells and extracellular vesicles.

EXPERT OPINION

While there are a plethora of molecular markers for stroke diagnosis that have been reported, they have yet to be FDA-cleared. Possible reasons include the inability for these markers to appear in sufficient quantities for highly sensitive clinical decisions within the rt-PA therapeutic time.

Synthesis, Characterization, and In Vivo Evaluation of Desmethyl Anethole Trithione Phosphate Prodrug for Ameliorating Cerebral Ischemia-Reperfusion Injury in Rats

Anethol trithione (ATT) has a wide range of physiological activities, but its use is limited due to its poor water solubility. To improve the solubility of ATT, we synthesized and characterized a novel phosphate prodrug (ATXP) relying on the availability of the hydroxy group in 5-(4-hydroxyphenyl)-3H-1,2-dithiole3-thione (ATX), which was transformed from ATT rapidly and extensively in vivo. Our results showed that ATXP significantly improved drug solubility. ATXP was rapidly converted to ATX and reached a maximum plasma concentration with a T _max of approximately 5 min after intravenous (iv) administration. Furthermore, after the oral administration of ATXP, the C _max was 3326.30 ± 566.50 ng/mL, which was approximately 5-fold greater than that of the parent drug form, indicating that ATXP has greater absorption than that of ATT. Additionally, the oral phosphate prodrug ATXP increased the ATX in the area under the plasma concentration vs time curves (AUC_0-t = 3927.40 ± 321.50 and AUC_0-∞ = 4579.0 ± 756.30), making its use in practical applications more meaningful. Finally, compared to the vehicle, ATXP was confirmed to maintain the bioactivity of the parent drug for a significant reduction in infarct volume 24 h after reperfusion. Based on these findings, the phosphate prodrug ATXP is a potentially useful water-soluble prodrug with improved pharmacokinetic properties.

Long noncoding RNA NEAT1 correlates with higher disease risk, worse disease condition, decreased miR-124 and miR-125a and predicts poor recurrence-free survival of acute ischemic stroke

Objective

This study aimed to investigate the predictive value of long noncoding RNA nuclear enriched abundant transcript 1 (lncRNA NEAT1) for acute ischemic stroke (AIS) risk and to explore the correlation of lncRNA NEAT1 with disease severity, inflammation, recurrence and target microRNAs in patients with AIS.

Methods

210 patients with AIS and 210 controls were enrolled, and their peripheral blood samples were collected within 24 hours after admission and collected on the enrollment, respectively. lncRNA NEAT1 expression was detected by quantitative polymerase chain reaction (qPCR). For patients with AIS, disease severity was evaluated by National Institute of Health Stroke Scale (NIHSS) score; plasma concentrations of inflammatory factors and lncRNA NEAT1 target microRNAs were measured by enzyme‐linked immune sorbent assay and qPCR, respectively; stroke recurrence and death were recorded; and recurrence‐free survival (RFS) was calculated.

Results

lncRNA NEAT1 expression was elevated in patients with AIS compared with controls, and it had a good predictive value for AIS risk (area under the curve [AUC]: 0.804 [95% confidence interval [CI]: 0.763‐0.845]). In patients with AIS, lncRNA NEAT1 expression positively correlated with NIHSS score and inflammatory factor levels including C‐reactive protein (CRP), tumor necrosis factor (TNF)‐α, interleukin (IL)‐6, IL‐8, and IL‐22, while it negatively correlated with anti‐inflammatory cytokine IL‐10 level. Besides, lncRNA NEAT1 predicted increased recurrence/death risk (AUC: 0.641 [95% CI: 0.541‐0.741]), and its high expression correlated with worse RFS. Additionally, lncRNA NEAT1 expression negatively correlated with microRNA‐124 and microRNA‐125a expressions.

Conclusion

LncRNA NEAT1 may serve as a novel biomarker for assisting AIS management and prognosis.

The 100 most cited articles in the endovascular management of acute ischemic stroke

BACKGROUND AND PURPOSE

Endovascular thrombectomy (EVT) has revolutionized the management of acute ischemic stroke. Landmark clinical trials have shown EVT to be one of the most efficacious interventions in clinical medicine over the past 5 years. A method of recognition for an article in the scientific community is to use a citation rank list, in order to identify the seminal works in the academic medical literature. The objective of this study was to characterize the 100 most highly cited articles assessing endovascular management of acute ischemic stroke.

METHODS

We conducted a retrospective bibliometric analysis using the Web of Science Citation Index Expanded database for the most cited works in the endovascular management of acute ischemic stroke. Citation count was used to rank the top 100 articles, which were then analyzed for authorship, year of publication, subject, study type, level of evidence, and subject.

RESULTS

The mean number of citations was 245 (range 65-1726) and 394 on Google Scholar. The top 100 articles were cited an average of 43.9 times per year and published in 21 journals in the past two decades. The majority of papers (62) were classified as constituting levels 1, 2, or 3 evidence, and included 17 randomized controlled trials. Approximately two-thirds of the top 100 articles originated from the USA.

CONCLUSIONS

This study details the most cited articles in the endovascular management of acute ischemic stroke, and furthermore shows that a high proportion of level I evidence exists for this intervention.