Composition and Organization of Acute Ischemic Stroke Thrombus: A Wealth of Information for Future Thrombolytic Strategies.

peer reviewedDuring the last decade, significant progress has been made in understanding thrombus composition and organization in the setting of acute ischemic stroke (AIS). In particular, thrombus organization is now described as highly heterogeneous but with 2 preserved characteristics: the presence of (1) two distinct main types of areas in the core-red blood cell (RBC)-rich and platelet-rich areas in variable proportions in each thrombus-and (2) an external shell surrounding the core composed exclusively of platelet-rich areas. In contrast to RBC-rich areas, platelet-rich areas are highly complex and are mainly responsible for the thrombolysis resistance of these thrombi for the following reasons: the presence of platelet-derived fibrinolysis inhibitors in large amounts, modifications of the fibrin network structure resistant to the tissue plasminogen activator (tPA)-induced fibrinolysis, and the presence of non-fibrin extracellular components, such as von Willebrand factor (vWF) multimers and neutrophil extracellular traps. From these studies, new therapeutic avenues are in development to increase the fibrinolytic efficacy of intravenous (IV) tPA-based therapy or to target non-fibrin thrombus components, such as platelet aggregates, vWF multimers, or the extracellular DNA network

Intravenous Administration of Human Adipose Derived-Mesenchymal Stem Cells Is Not Efficient in Diabetic or Hypertensive Mice Subjected to Focal Cerebral Ischemia

Copyright © 2019 Mangin, Cogo, Moisan, Bonnin, Maïer and Kubis.As the second cause of death and cognitive decline in industrialized countries, stroke is a major burden for society. Vascular risks factors such as hypertension and diabetes are involved in most stroke patients, aggravate stroke severity, but are still poorly taken into account in preclinical studies. Microangiopathy and sustained inflammation are exacerbated, likely explaining the severity of stroke in those patients. We sought to demonstrate that intravenous administration of human adipose derived-mesenchymal stem cells (hADMSC) that have immunomodulatory properties, could accelerate sensorimotor recovery, prevent long-term spatial memory impairment and promote neurogenesis, in diabetic or hypertensive mice, subjected to permanent middle cerebral artery occlusion (pMCAo). Diabetic (streptozotocin IP) or hypertensive (L-NAME in drinking water) male C57Bl6 mice subjected to pMCAo, were treated by hADMSC (500,000 cells IV) 2 days after cerebral ischemia induction. Infarct volume, neurogenesis, microglial/macrophage density, T-lymphocytes density, astrocytes density, and vessel density were monitored 7 days after cells injection and at 6 weeks. Neurological sensorimotor deficit and spatial memory were assessed until 6 weeks post-stroke. Whatever the vascular risk factor, hADMSC showed no effect on functional sensorimotor recovery or cognitive decline prevention at short or long-term assessment, nor significantly modified neurogenesis, microglial/macrophage, T-lymphocytes, astrocytes, and vessel density. This work is part of a European program (H2020, RESSTORE). We discuss the discrepancy of our results with those obtained in rats and the optimal cell injection time frame, source and type of cells according to the species stroke model. A comprehensive understanding of the mechanisms preventing recovery should help for successful clinical translation, but first could allow identifying good and bad responders to cell therapy in stroke.The RESSTORE project received funding from the European Union’s Horizon 2020 Research and Innovation Programme under the Grant Agreement No. 681044 RESSTORE project (www.resstore.eu) and GM was directly funded by the RESSTORE project

Evaluation of CATCHVIEW Versus Standard Stent Retrievers for Endovascular Therapy: Results From the ETIS Registry

Background The CATCHVIEW device (Balt) is a last‐generation stent retriever designed for endovascular therapy. We aimed to compare the CATCHVIEW device with standard stent retrievers (SSRs) using propensity score methods and assess the noninferiority of CATCHVIEW versus SSRs. Methods We used the ETIS (Endovascular Treatment in Ischemic Stroke) multicenter (13 centers), prospective registry to compare clinical and radiological data of patients treated with CATCHVIEW or SSRs as a first‐line strategy. Procedural outcomes (successful, near‐perfect, perfect reperfusion after first‐line strategy, and at the end of endovascular therapy), clinical outcomes (modified Rankin Scale at 90 days), and safety outcomes (symptomatic intracranial hemorrhage, mortality at 90 days) were compared after propensity score matching. Noninferiority of CATCHVIEW was established if the prespecified lower bound of the 95% CI was >−10%. Results From March 2017 to March 2020, 171 patients treated first‐line by CATCHVIEW were matched to 617 patients treated first‐line by an SSR. In the propensity score–matched cohort, successful reperfusion after first‐line strategy was achieved in 73.9% and 76.2% in the CATCHVIEW and SSR groups, respectively (absolute difference, −2.3%; 1‐sided 95% CI, −7.0% to ∞), demonstrating noninferiority of CATCHVIEW versus SSR. CATCHVIEW was associated with better near‐perfect (matched relative risk, 1.15; [95% CI, 1.00–1.31]) and perfect (matched relative risk, 1.26; [95% CI, 1.07–1.47]) reperfusion rates at the end of endovascular therapy and favorable 90‐day outcomes (matched relative risk, 1.27; [95% CI, 1.03–1.55]). Safety outcomes were comparable. Conclusions In this propensity score–matched cohort, we demonstrated the noninferiority of CATCHVIEW compared with SSR, as the first‐line strategy for successful reperfusion. CATCHVIEW achieved higher reperfusion rates at the end of endovascular therapy and higher rates of favorable outcomes at 90 days

Anaesthesia and haemodynamic management of acute ischaemic stroke patients before, during and after endovascular therapy

International audienceEndovascular therapy (EVT) is now standard of care for eligible patients with acute ischaemic stroke caused by large vessel occlusion in the anterior circulation. EVT can be performed with general anaesthesia (GA) or with monitored anaesthesia care, involving local anaesthesia with or without conscious sedation (LA/CS). Controversies remain regarding the optimal choice of anaesthetic strategy and observational studies suggested poorer functional outcome and higher mortality in patients treated under GA, essentially because of its haemodynamic consequences and the delay to put patients under GA. However, these studies are limited by selection bias, the most severe patients being more likely to receive GA and recent randomised trials and meta-analysis showed that protocol-based GA compared with LA/CS is significantly associated with less disability at 3 months. Unlike for intravenous thrombolysis, few data exist to guide management of blood pressure (BP) before and during EVT, but arterial hypotension should be avoided as long as the occlusion persists. BP targets following EVT should probably be adapted to the degree of recanalisation and the extent of ischaemia. Lower BP levels may be warranted to prevent reperfusion injuries even if prospective haemodynamic management evaluations after EVT are lacking

The Benefit of a Complete over a Successful Reperfusion Decreases with Time

International audienceObjective: Time from stroke onset to reperfusion (TSOR) is strongly associated with outcomes after endovascular treatment. A near-to-complete or complete reperfusion (modified Treatment in Cerebral Ischemia [mTICI] 2c–3) is associated with improved outcomes compared with a successful reperfusion (mTICI 2b). However, it is unknown whether this association remains stable as TSOR increases. Therefore, we sought to investigate the association between TSOR and outcomes according to the reperfusion status. Methods: We analyzed data from the Endovascular Treatment in Ischemic Stroke registry, a prospective, observational, multicentric study of acute ischemic stroke patients treated with endovascular treatment in 21 centers in France. We included patients with anterior occlusions (M1, internal carotid artery, tandem), with a known time of symptom onset. Outcomes were early neurological improvement at 24 hours and favorable outcome (modified Rankin Scale between 0 and 2) at 90 days. Results: Overall, 4,444 patients were analyzed. Compared with a mTICI 2b, a mTICI 2c-3 at 1 hour was associated with higher mean marginal probabilities of early neurological improvement (25.6%, 95% CI 11.7–39.5, p = 0.0003) and favorable outcome (15.2%, 95% CI 3.0–27.4, p = 0.0143), and progressively declined with TSOR. The benefit of a mTICI 2c-3 over a mTICI 2b was no longer significant regarding the rates of early neurological improvement and favorable outcome after a TSOR of 414 and 344 minutes, respectively. Interpretation: The prognostic value of a complete over a successful reperfusion progressively declined with time, and no difference regarding the rates of favorable outcome was observed between a complete and successful reperfusion beyond 5.7 hours. ANN NEUROL 2023;93:934–941

Increased serum QUIN/KYNA is a reliable biomarker of post-stroke cognitive decline

International audienceBackground: Strokes are becoming less severe due to increased numbers of intensive care units and improved treatments. As patients survive longer, post-stroke cognitive impairment (PSCI) has become a major health public issue. Diabetes has been identified as an independent predictive factor for PSCI. Here, we characterized a clinically relevant mouse model of PSCI, induced by permanent cerebral artery occlusion in diabetic mice, and investigated whether a reliable biomarker of PSCI may emerge from the kynurenine pathway which has been linked to inflammatory processes.Methods: Cortical infarct was induced by permanent middle cerebral artery occlusion in male diabetic mice (streptozotocin IP). Six weeks later, cognitive assessment was performed using the Barnes maze, hippocampi long-term potentiation using microelectrodes array recordings, and neuronal death, white matter rarefaction and microglia/macrophages density assessed in both hemispheres using imunohistochemistry. Brain and serum metabolites of the kynurenin pathway were measured using HPLC and mass fragmentography. At last, these same metabolites were measured in the patient's serum, at the acute phase of stroke, to determine if they could predict PSCI 3 months later.Results: We found long-term spatial memory was impaired in diabetic mice 6 weeks after stroke induction. Synaptic plasticity was completely suppressed in both hippocampi along with increased neuronal death, white matter rarefaction in both striatum, and increased microglial/macrophage density in the ipsilateral hemisphere. Brain and serum quinolinic acid concentrations and quinolinic acid over kynurenic acid ratios were significantly increased compared to control, diabetic and non-diabetic ischemic mice, where PSCI was absent. These putative serum biomarkers were strongly correlated with degradation of long-term memory, neuronal death, microglia/macrophage infiltration and white matter rarefaction. Moreover, we identified these same serum biomarkers as potential predictors of PSCI in a pilot study of stroke patients.Conclusions: we have established and characterized a new model of PSCI, functionally and structurally, and we have shown that the QUIN/KYNA ratio could be used as a surrogate biomarker of PSCI, which may now be tested in large prospective studies of stroke patients

Thrombectomy with or without Intravenous Thrombolytics in Basilar Artery Occlusion

International audienceObjective: Two randomized trials demonstrated the benefit of endovascular therapy (EVT) in patients suffering from a stroke due to a basilar artery occlusion (BAO). However, intravenous thrombolytic (IVT) use before EVT was low in these trials, questioning the added value of this treatment in this setting. We sought to investigate the efficacy and safety of EVT alone compared to IVT + EVT in stroke patients with a BAO. Methods: We analyzed data from the Endovascular Treatment in Ischemic Stroke registry, a prospective, observational, multicenter study of acute ischemic stroke patients treated with EVT in 21 centers in France between 1 January 2015 and 31 December 2021. We included patients with BAO and/or intracranial vertebral artery occlusion and compared patients treated with EVT alone versus IVT + EVT after propensity score (PS) matching. Variables selected for the PS were pre-stroke mRS, dyslipidemia, diabetes, anticoagulation, admission mode, baseline NIHSS and ASPECTS, type of anesthesia, and time from symptom onset to puncture. Efficacy outcomes were good functional outcome (modified Rankin Scale [mRS] 0-3) and functional independence (mRS 0–2) at 90 days. Safety outcomes were symptomatic intracranial hemorrhages and all-cause mortality at 90 days. Results: Among 385 patients, 243 (134 EVT alone and 109 IVT + EVT) were included after PS matching. There was no difference between EVT alone and IVT + EVT regarding good functional outcome (adjusted odd ratio [aOR] labeling = 1.27, 95% confidence interval [CI], 0.68–2.37, p = 0.45) and functional independence (aOR = 1.50, 95% CI, 0.79–2.85, p = 0.21). Symptomatic intracranial hemorrhage and all-cause mortality were also similar between the two groups (aOR = 0.42, 95% CI, 0.10–1.79, p = 0.24 and aOR = 0.56, 95% CI, 0.29–1.10, p = 0.09, respectively). Interpretation: In this PS matching analysis, EVT alone seemed to lead to similar neurological recovery than IVT + EVT, with comparable safety profile. However, given our sample size and the observational nature of this study, further studies are needed to confirm these findings. ANN NEUROL 2023;94:596–604

Role of Brain Imaging in the Prediction of Intracerebral Hemorrhage Following Endovascular Therapy for Acute Stroke

International audienceCurrently most acute ischemic stroke patients presenting with a large vessel occlusion are treated with endovascular therapy (EVT), which results in high rates of successful recanalization. Despite this success, more than half of EVT-treated patients are significantly disabled 3 months later partly due to the occurrence of post-EVT intracerebral hemorrhage. Predicting post-EVT intracerebral hemorrhage is important for individualizing treatment strategies in clinical practice (eg, safe initiation of early antithrombotic therapies), as well as in selecting the optimal candidates for clinical trials that aim to reduce this deleterious outcome. Emerging data suggest that brain and vascular imaging biomarkers may be particularly relevant since they provide insights into the ongoing acute stroke pathophysiology. In this review/perspective, we summarize the accumulating literature on the role of cerebrovascular imaging biomarkers in predicting post-EVT–associated intracerebral hemorrhage. We focus on imaging acquired before EVT, during the EVT procedure, and in the early post-EVT time frames when new therapeutic therapies could be tested. Accounting for the complex pathophysiology of post-EVT–associated intracerebral hemorrhage, this review may provide some guidance for future prospective observational or therapeutic studies

Effect of Baseline Antihypertensive Treatments on Stroke Severity and Outcomes in the BP TARGET Trial

International audienceBACKGROUND: Acute ischemic stroke (AIS) patients with a history of hypertension experience worse outcomes, which may be explained by a deleterious impact of the renin-angiotensin system (RAS) overactivation. We sought to investigate whether prestroke antihypertensive treatments (AHT) influenced baseline stroke severity and neurological outcomes, in patients with AIS successfully treated by endovascular therapy. METHODS: We performed a post hoc analysis of the BP TARGET trial (Blood Pressure Target in Acute Stroke to Reduce Hemorrhage After Endovascular Therapy) and included hypertensive patients with available data regarding AHT at admission, categorized as RAS inhibitors (ACE [angiotensin-converting enzyme] inhibitors, ARBs [angiotensin 2 receptor blockers], and β-blockers) and non-RAS inhibitors (calcium channel blockers and diuretics). Associations of each AHT with National Institutes of Health Stroke Scale (NIHSS) score at baseline were investigated in linear mixed model adjusted for the number of treatments and center. Associations of each AHT with 24-hour NIHSS change, intracranial hemorrhage were performed using linear mixed model adjusted for baseline NIHSS, the number of treatments, center, age, and sex and adjusted for age, sex, diabetes, and current smoking for favorable outcome. All analyses were performed on cases-available data regarding the low number of missing data. RESULTS: Overall, 203 patients with at least one AHT were included. Patients under non-RAS inhibitor treatments had a higher NIHSS score at baseline (adjusted mean difference=3.28 [95% CI, 1.33-5.22]; P=0.001). Conversely, patients under RAS inhibitor treatments had a lower baseline NIHSS score (adjusted mean difference=-2.81 [95% CI, -5.37 to -0.25]; P=0.031). Intracranial hemorrhage occurrence was significantly more frequent in patients under non-RAS inhibitor treatments (adjusted odds ratio of 2.48 [95% CI, 1.12-5.47]; P=0.025). Conversely, the use of RAS inhibitor treatments before AIS was not associated with higher odds of radiographic intracranial hemorrhage. Patients with non-RAS inhibitor treatments had less improvement of NIHSS at 24 hours compared with patients without (adjusted mean difference, 2.83 [95% CI, -0.16 to 5.81]; P=0.063). Baseline RAS inhibitor or noninhibitor treatments were not associated with favorable outcome. CONCLUSIONS: We showed an opposite effect of baseline AHT, based on their effect on the RAS. Patients treated with RAS inhibitor agents before AIS exhibited less severe AIS compared with patients under non-RAS inhibitor treatments, developed less intracranial hemorrhage at 24 hours and had a trend toward better NIHSS score at 24 hours. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT031606