Standards of Practice in Acute Ischemic Stroke Intervention: International Recommendations

Procedural factors associated with successful recanalization in patients with acute ischemic stroke treated with endovascular thrombectomy-a nationwide register-based observational study

INTRODUCTION

Several studies have addressed technical aspects of endovascular thrombectomy (EVT), but it is not well known how procedural factors contribute to technical success in routine healthcare. The aim was to explore factors associated with technically successful EVT on nationwide scale.

METHODS

We did an observational register-based study assessing factors associated with technical success off anterior circulation EVT in Sweden. The main outcome was successful recanalization defined as modified treatment in cerebral ischemia score 2b-3. The association between baseline and treatment variables and successful recanalization were explored using Chi-square(d) test and univariable logistic regression. Multivariable logistic regression was used to define predictors of successful recanalization.

RESULTS

The study included 3211 patients treated during 2015 to 2020. Successful recanalization was achieved in 83.1% (2667) with a gradual improvement in technical outcome over the period. After adjustment for age and occlusion location, thet use of general anesthesia, balloon guide catheter (BGC) and an operator with an overall success rate of >85% were independent predictors of successful recanalization. An overall operator success rate of <80% or 80-85%, and an annual center volume lower than 50 were predicitors of recanalization failure.

CONCLUSION

This study illustrates factors associated with procedural success in endovascular thrombectomy on a nationwide scale including the use of general anesthesia, BGC, annual center volumes >50 cases per year and the overall success rate of the individual operator. It highlights the potential benefit of systematic performance measurements, benchmarking, and continuous training to bring all centers and operators to the highest level of performance.

Antiplatelet effect of ginkgo diterpene lactone meglumine injection in acute ischemic stroke: A randomized, double-blind, placebo-controlled clinical trial

This study was designed to evaluate antiplatelet effect and therapeutic effect of ginkgo diterpene lactone meglumine injection (GDLI) in acute ischemic stroke (AIS) patients. In this randomized, double-blind, placebo-controlled trial, we randomly assigned 70 inpatients within 48 hr after the onset of AIS to combination therapy with GDLI and aspirin (GDLI at a dose of 25 mg/d for 14 days plus aspirin at a dose of 100 mg/d for 90 days) or to placebo plus aspirin in a ratio of 1:1. Platelet function, the National Institute of Health Stroke Scale (NIHSS), and the modified Rankin Scale (mRS) were evaluated. A good outcome was defined as NIHSS scores decrease ≥5 or mRS scores decrease ≥2. Results showed that arachidonic acid induced maximum platelet aggregation rate (AA-MAR) and mean platelet volume (MPV) of the GDLI-aspirin group were much lower than that of the aspirin group (p = 0.013 and p = 0.034, respectively) after the 14-day therapy. The combination of GDLI and aspirin was superior to aspirin alone, and had significant impact on the good outcome at day 90 (ORadj 7.21 [95%CI, 1.03-50.68], p = 0.047). In summary, GDLI has antiplatelet effect and can improve the prognosis of AIS patients.

Circulating Leukocyte as an Inflammatory Biomarker: Association with Fibrinogen and Neuronal Damage in Acute Ischemic Stroke

Background and Purpose

Leukocytes and fibrinogen are inflammatory markers involved in circulating and central inflammatory response after ischemic stroke. However, the interaction between circulating leukocytes and serum fibrinogen and neuronal injury in acute ischemic stroke (AIS) patients is still unclear. The present study aimed to investigate the association between circulating leukocyte and serum fibrinogen and neuronal injury respectively in AIS.

Methods

A cross-section study with 431 hospitalized AIS patients from department of neurology was performed. Circulating leukocytes and fibrinogen were measured, and neuron-specific enolase (NSE) was detected to evaluate central neuronal damage. A propensity score matching method was used to minimize the effects of confounding factors. The relationship between leukocytes and NSE and fibrinogen was analyzed by linear curve fitting analysis and multiple logistic regression models respectively.

Results

The mean levels of NSE, leukocyte, and fibrinogen were significantly higher in the matched AIS group (n=89) than those of in the healthy control group (n=89) (all p<0.05). Both serum NSE and fibrinogen were increased with the increasing of leukocyte in AIS patients (both p<0.05). Smoothed plots suggested that there are linear relationships between leukocyte and NSE and fibrinogen respectively. Multiple logistic regression analysis showed the OR (95%) for the relationship between leukocyte and high NSE were 1.13 (1.01-1.26, p=0.031) and 1.13 (1.00-1.28, p=0.048), and between leukocyte and high fibrinogen were 1.40 (1.22-1.61, p<0.001) and 1.35 (1.15-1.58, p<0.001) in all AIS patients before and after adjusting for potential confounders.

Conclusion

Our study suggests that elevated circulating leukocyte was associated with high fibrinogen and neuronal injury in AIS. Therefore, there may be potential targets among circulating leukocyte, fibrinogen and NSE that should be intervened to reduce inflammatory reaction after ischemic stroke.

Association between type of intervention center and outcomes after endovascular treatment for acute ischemic stroke: Results from the MR CLEAN Registry

Background:

Endovascular treatment (EVT) for acute ischemic stroke (AIS) is performed in intervention centers that provide the full range of neuro(endo)vascular care (level 1) and centers that only perform EVT for AIS (level 2). We compared outcomes between these center types and assessed whether differences in outcomes could be explained by center volume (CV).

Patients and methods:

We analyzed patients included in the MR CLEAN Registry (2014–2018), a registry of all EVT-treated patients in the Netherlands. Our primary outcome was the shift on the modified Rankin scale (mRS) after 90 days (ordinal regression). Secondary outcomes were the NIHSS 24–48 h post-EVT, door-to-groin time (DTGT), procedure time (linear regression), and recanalization (binary logistic regression). We compared outcomes between level 1 and 2 centers using multilevel regression models, with center as random intercept. We adjusted for relevant baseline factors, and in case of observed differences, we additionally adjusted for CV.

Results:

Of the 5144 patients 62% were treated in level 1 centers. We observed no significant differences between center types in mRS (adjusted(a)cOR: 0.79, 95% CI: 0.40 to 1.54), NIHSS (aβ: 0.31, 95% CI: −0.52 to 1.14), procedure duration (aβ: 0.88, 95% CI: −5.21 to 6.97), or DTGT (aβ: 4.24, 95% CI: −7.09 to 15.57). The probability for recanalization was higher in level 1 centers compared to level 2 centers (aOR 1.60, 95% CI: 1.10 to 2.33), and this difference probably depended on CV.

Conclusions:

We found no significant differences, that were independent of CV, in the outcomes of EVT for AIS between level 1 and level 2 intervention centers.

Impact of weather and pollution on the rate of cerebrovascular events in a large metropolitan area

BACKGROUND

Despite mounting evidence, there is uncertainty on the impact of the interplay between weather and pollution features on the risk of acute cerebrovascular events (CVE). We aimed at appraising role of weather and pollution on the daily risk of CVE.

METHODS

Anonymized data from a hub CVE center in a large metropolitan area were collected and analyzed according to weather (temperature, pressure, humidity, and rainfall) and pollution (carbon monoxide [CO], nitrogen dioxide [NO2], nitrogen oxides [NOX], ozone [O3], and particulate matter [PM]) on the same and the preceding days. Poisson regression and time series analyses were used to appraise the association between environmental features and daily CVE, distinguishing also several subtypes of events.

RESULTS

We included a total of 2534 days, with 1363 days having ≥1 CVE, from 2012 to 2017. Average daily rate was 1.56 (95% confidence interval: 1.49; 1.63) for CVE, with other event rates ranging between 1.42 for stroke and 0.01 for ruptured intracranial aneurysm. Significant associations were found between CVE and temperature, pressure, CO, NO2, NOX, O3, and PM <10 µm (all P<0.05), whereas less stringent associations were found for humidity, rainfall, and PM <2.5 µm. Time series analysis exploring lag suggested that associations were stronger at same-day analysis (lag 0), but even environmental features predating several days or weeks were significantly associated with events. Multivariable analysis suggested that CO (point estimate 1.362 [1.011; 1.836], P=0.042) and NO2 (1.011 [1.005; 1.016], P<0.001) were the strongest independent predictors of CVE.

CONCLUSIONS

Environmental features are significantly associated with CVE, even several days before the actual event. Levels of CO and NO2 can be potentially leveraged for population-level interventions to reduce the burden of CVE.

Detection of Unilateral Arm Paresis after Stroke by Wearable Accelerometers and Machine Learning

Recent advances in stroke treatment have provided effective tools to successfully treat ischemic stroke, but still a majority of patients are not treated due to late arrival to hospital. With modern stroke treatment, earlier arrival would greatly improve the overall treatment results. This prospective study was performed to asses the capability of bilateral accelerometers worn in bracelets 24/7 to detect unilateral arm paralysis, a hallmark symptom of stroke, early enough to receive treatment. Classical machine learning algorithms as well as state-of-the-art deep neural networks were evaluated on detection times between 15 min and 120 min. Motion data were collected using triaxial accelerometer bracelets worn on both arms for 24 h. Eighty-four stroke patients with unilateral arm motor impairment and 101 healthy subjects participated in the study. Accelerometer data were divided into data windows of different lengths and analyzed using multiple machine learning algorithms. The results show that all algorithms performed well in separating the two groups early enough to be clinically relevant, based on wrist-worn accelerometers. The two evaluated deep learning models, fully convolutional network and InceptionTime, performed better than the classical machine learning models with an AUC score between 0.947-0.957 on 15 min data windows and up to 0.993-0.994 on 120 min data windows. Window lengths longer than 90 min only marginally improved performance. The difference in performance between the deep learning models and the classical models was statistically significant according to a non-parametric Friedman test followed by a post-hoc Nemenyi test. Introduction of wearable stroke detection devices may dramatically increase the portion of stroke patients eligible for revascularization and shorten the time to treatment. Since the treatment effect is highly time-dependent, early stroke detection may dramatically improve stroke outcomes.

Interdisciplinary management of acute ischaemic stroke: Current evidence training requirements for endovascular stroke treatment. Position Paper from the ESC Council on Stroke and the European Association for Percutaneous Cardiovascular Interventions with the support of the European Board of Neurointervention

This ESC Council on Stroke/EAPCI/EBNI position paper summarizes recommendations for training of cardiologists in endovascular treatment of acute ischaemic stroke. Interventional cardiologists adequately trained to perform endovascular stroke interventions could complement stroke teams to provide the 24/7 on call duty and thus to increase timely access of stroke patients to endovascular treatment. The training requirements for interventional cardiologists to perform endovascular therapy are described in details and should be based on two main principles: (i) patient safety cannot be compromised, (ii) proper training of interventional cardiologists should be under supervision of and guaranteed by a qualified neurointerventionist and within the setting of a stroke team. Interdisciplinary cooperation based on common standards and professional consensus is the key to the quality improvement in stroke treatment.

Endovascular thrombectomy 2020: open issues

Mechanical thrombectomy is now well - established first - line treatment for selected patients with large artery occlusions of the anterior circulation. However, number of technical and procedural issues remains open to assure optimal outcomes in majority of patients including those suffering from posterior circulation perfusion defects. This brief review addresses some of the open issues and refers to the ongoing trials to close the existing knowledge gaps.

Association Between Low-Density Lipoprotein Cholesterol and Platelet Distribution Width in Acute Ischemic Stroke

Objective: Elevated low-density lipoprotein cholesterol (LDL-C) is an established risk factor for ischemic stroke; however, whether LDL-C affects the platelet deformation function in the peripheral blood circulation in patients with acute ischemic stroke (AIS) is unknown. The present study aimed to investigate the relationship between LDL-C and platelet distribution width (PDW) in AIS patients. Methods: We conducted a cross-sectional hospitalized-based study of consecutive 438 patients with AIS within 24 h. Blood samples were collected upon admission and prior to drug administration, and LDL-C and PDW (a parameter that reflects the heterogeneity of platelet volume) were assessed. The relationship between LDL-C and PDW were analyzed by linear curve fitting analyses. Crude and adjusted beta coefficients of LDL-C for PDW with 95% confidence intervals were analyzed using multivariate-adjusted linear regression models. Results: The PDW was significantly higher in the high LDL-C group compared with those in the normal LDL-C group (16.28 ± 0.37 fl vs. 16.08 ± 0.37 fl, p < 0.001). Adjusted smoothed plots suggested that there are linear relationships between LDL-C and PDW, and the Pearson's correlation coefficient (95%) was 0.387 (0.304-0.464, p < 0.001). The beta coefficients (95% CI) between LDL-C and PDW were 0.15 (0.12-0.18, p < 0.001) and 0.14 (0.11-0.18, p < 0.001), respectively, in AIS patients before and after adjusting for potential confounders. Conclusion: Our study suggested that the elevated LDL-C level was related to increased PDW among AIS patients.

In-Hospital Intravenous Thrombolysis Offers No Benefit in Mechanical Thrombectomy in Optimized Tertiary Stroke Center Setting

Purpose

Mechanical thrombectomy (MT) is the first-line treatment in acute stroke patients presenting with large vessel occlusion (LVO). The efficacy of intravenous thrombolysis (IVT) prior to MT is being contested. The objective of this study was to evaluate the efficacy of MT without IVT in patients with no contraindications to IVT presenting directly to a tertiary stroke center with acute anterior circulation LVO.

Materials and Methods

We collected the data of 106 acute stroke patients who underwent MT in a single high-volume stroke center. Patients with anterior circulation LVO eligible for IVT and directly admitted to our institution who subsequently underwent MT were included. We recorded baseline clinical, laboratory, procedural, and imaging variables and technical, imaging, and clinical outcomes. The effect of intravenous thrombolysis on 3-month clinical outcome (mRS) was analyzed with univariate tests and binary and ordinal logistic regression analysis.

Results

Fifty-eight out of the 106 patients received IVT + MT. These patients had 2.6-fold higher odds of poorer clinical outcome in mRS shift analysis (p = 0.01) compared to MT-only patients who had excellent 3-month clinical outcome (mRS 0–1) three times more often (p = 0.009). There were no significant differences between the groups in process times, mTICI, or number of hemorrhagic complications. A trend of less distal embolization and higher number of device passes was observed among the MT-only patients.

Conclusions

MT without prior IVT was associated with an improved overall three-month clinical outcome in acute anterior circulation LVO patients.

Supplementary Information

The online version of this article (10.1007/s00270-020-02727-8) contains supplementary material, which is available to authorized users.

Coverage of the requirements of first and second level stroke unit in Italy

Background and aim

In the scientific literature, there is unanimous consensus that hospitalization in stroke unit (SU) is the most important treatment for stroke patients. In this regard, the Act number 70/2015 by the Italian government identified specific skills that contribute to a classification of SU and outlined a “hub and spoke” stroke network. The aim of our study was to check the coverage of requirements of first and second level SU in the national territory and to shed light on any deficit or misdistribution of resources.

Material and methods

In 2019, a survey on the current situation related to stroke care in Italy was carried out by the Italian Society of Neurology (SIN), The Italian Stroke Organization (ISO), and the Association for the Fight against Stroke (A.L.I.Ce).

Results

First level SU was found to be 58 against a requirement, according to the Act 70/2015, of 240. Second level SU was found to be 52 compared with an expected requirement of 60. Neurointerventionists were 280 nationally, with a requirement of 240. A misdistribution of resources within individual regions was often seen.

Conclusions

The survey demonstrated a severe shortage of beds dedicated to cerebrovascular diseases, mainly because of lack of first level SU, especially in central and southern Italy. It also suggests that the current hub and spoke system is not yet fully implemented across the country and that resources should be better distributed in order to ensure uniform and fair care for all stroke patients on the whole territory.

Electronic supplementary material

The online version of this article (10.1007/s10072-020-04616-x) contains supplementary material, which is available to authorized users.

Endovascular treatment for ischemic stroke beyond the time window: A meta-analysis

Currently, endovascular treatment has been proven to be effective when conducted within 6 hours of symptom onset. However, when patients have symptoms for more than 6 hours, have a daytime-unwitnessed stroke (DUS) or wake up with a stroke (wake-up stroke, WUS), the safety and efficacy of endovascular treatment need to be further elucidated. Therefore, we performed a systematic review and meta-analysis to compare the clinical outcomes of endovascular treatment in patients with ischemic stroke beyond the time window with that ≤6 hours. PubMed, EMBASE, and Ovid MEDLINE were searched from inception to November 2018. The following outcomes were evaluated by a random-effects model: efficacy outcomes, that is, functional independence and successful recanalization, and safety outcomes, that is, symptomatic intracranial hemorrhage and mortality. Subgroup analyses were also performed to examine whether patient or study characteristics were associated with the outcomes. Nine observational studies, including 5192 patients (1414 patients with extended time windows [ETWs]; 3778 patients ≤6 hours), were eligible for analysis. The overall analysis demonstrated that the functional independence was worse in patients with ETWs vs those ≤6 hours (OR, 0.78; 95% CI, 0.68-0.90, P = .0006). However, subgroup analysis showed that there was no significant difference in functional independence between the two groups when patients were selected for a perfusion mismatch by imaging (OR, 1.00; 95% CI, 0.70-1.43, P = 1.000). Therefore, compared with a window ≤6 hours, endovascular treatment with ETWs for ischemic stroke may not result in poor outcomes when patients are typically selected by perfusion techniques.

Astrocytic endothelin-1 overexpression promotes neural progenitor cells proliferation and differentiation into astrocytes via the Jak2/Stat3 pathway after stroke

Background

Endothelin-1 (ET-1) is synthesized and upregulated in astrocytes under stroke. We previously demonstrated that transgenic mice over-expressing astrocytic ET-1 (GET-1) displayed more severe neurological deficits characterized by a larger infarct after transient middle cerebral artery occlusion (tMCAO). ET-1 is a known vasoconstrictor, mitogenic, and a survival factor. However, it is unclear whether the observed severe brain damage in GET-1 mice post stroke is due to ET-1 dysregulation of neurogenesis by altering the stem cell niche.

Methods

Non-transgenic (Ntg) and GET-1 mice were subjected to tMCAO with 1 h occlusion followed by long-term reperfusion (from day 1 to day 28). Neurological function was assessed using a four-point scale method. Infarct area and volume were determined by 2,3,5-triphenyltetra-zolium chloride staining. Neural stem cell (NSC) proliferation and migration in subventricular zone (SVZ) were evaluated by immunofluorescence double labeling of bromodeoxyuridine (BrdU), Ki67 and Sox2, Nestin, and Doublecortin (DCX). NSC differentiation in SVZ was evaluated using the following immunofluorescence double immunostaining: BrdU and neuron-specific nuclear protein (NeuN), BrdU and glial fibrillary acidic protein (GFAP). Phospho-Stat3 (p-Stat3) expression detected by Western-blot and immunofluorescence staining.

Results

GET-1 mice displayed a more severe neurological deficit and larger infarct area after tMCAO injury. There was a significant increase of BrdU-labeled progenitor cell proliferation, which co-expressed with GFAP, at SVZ in the ipsilateral side of the GET-1 brain at 28 days after tMCAO. p-Stat3 expression was increased in both Ntg and GET-1 mice in the ischemia brain at 7 days after tMCAO. p-Stat3 expression was significantly upregulated in the ipsilateral side in the GET-1 brain than that in the Ntg brain at 7 days after tMCAO. Furthermore, GET-1 mice treated with AG490 (a JAK2/Stat3 inhibitor) sh owed a significant reduction in neurological deficit along with reduced infarct area and dwarfed astrocytic differentiation in the ipsilateral brain after tMCAO.

Conclusions

The data indicate that astrocytic endothelin-1 overexpression promotes progenitor stem cell proliferation and astr ocytic differentiation via the Jak2/Stat3 pathway.

Standards for European training requirements in interventional neuroradiology : Guidelines by the Division of Neuroradiology/Section of Radiology European Union of Medical Specialists (UEMS), in cooperation with the Division of Interventional Radiology/UEMS, the European Society of Neuroradiology (ESNR), and the European Society of Minimally Invasive Neurological Therapy (ESMINT)

This document sets out standards for training in Interventional Neuroradiology (INR) in Europe. These standards have been developed by a working group of the European Society of Neuroradiology (ESNR) and the European Society of Minimally Invasive Neurological Therapy (ESMINT) on the initiative and under the umbrella of the Division of Neuroradiology/Section of Radiology of the European Union of Medical Specialists (UEMS).