Cerebral venous sinus thrombosis (CVST) is an uncommon venous thromboembolic event accounting for less than 1% of strokes resulting in brain parenchymal injuries. Diagnosis and prognosis are still ...challenging due to highly variable clinical course and etiologies. Beyond thrombosis, different CVST‐related parenchymal injuries may occur and include edema, ischemic strokes, and intra‐cerebral hemorrhage (ICH; i.e., parenchymal/subdural hematomas, and subarachnoid hemorrhages), which are identified in 40%–60% of patients without clearly identified mechanisms. In this perspective, experimental animal models contribute to the understanding of initiation, propagation, and resolution of thrombosis, as well as brain‐related damages. Last but not least, animal models may be useful to study new therapeutic approaches. In this review, we provide a comprehensive overview of CVST experimental models, focusing on their strengths, limits, and contribution to the current knowledge.
In patients with acute ischemic stroke (AIS) using a direct oral factor-Xa anticoagulant (DOAC) during the last 48 hours, a fixed plasma heparin-calibrated anti-Xa activity (0.5 IU/mL) was proposed ...as a threshold below which patients could be eligible for thrombolysis and/or thrombectomy. Besides, specific DOAC-calibrated anti-Xa thresholds up to 50 ng/mL have been proposed. However, specific DOAC assays are not widely available contrarily to low-molecularweight heparin (LMWH) anti-Xa activity. We developed and validated a nomogram for predicting apixaban and rivaroxaban concentrations based on LMWH anti-Xa assay.
Our prospective study included apixaban (n=325) and rivaroxaban (n=276) patients. On the same sample, we systematically measured specific DOAC concentration and LMWH anti-Xa activity, using STA®-Liquid-Anti-Xa (Stago) and specific DOAC- or LMWH-calibrators, respectively. The nomogram was built using quantifiable values for both assays on the derivation cohorts with a log-linear regression model. Model performances including sensitivity, specificity, and true positive rate for different thresholds were checked on the validation cohorts.
The models built from the derivation cohorts predicted that values <30 ng/mL and <50 ng/ mL DOAC thresholds corresponded to LMWH-anti-Xa values <0.10 IU/mL and <0.64 IU/mL for apixaban; <0.10 IU/mL and <0.71 IU/mL for rivaroxaban. The model accurately predicted apixaban/ rivaroxaban concentrations in the validation cohort.
This easy-to-use nomogram, developed with our reagent, allowed accurately predicting DOAC concentrations based on LMWH-anti-Xa results in emergency situations such as AIS when drug-specific assessments are not rapidly available. Using DOAC <50 ng/mL equivalent threshold, instead of the fixed LMWH <0.5 IU/mL one, would allow proposing thrombolysis to more patients.
Abstract Hyperuricaemia is commonly found in subjects with cardiovascular disease, but its role as risk factor is very controversial. Although several studies reported serum uric acid as a marker of ...an underlying pathophysiological process, other studies hypothesis a potential causal link between serum uric acid and cardiovascular diseases. Some studies suggest that uric acid is biologically active and may have an atherogenesis role in development of cardiovascular diseases, although the mechanisms are not fully understood. Other studies have shown that uric acid can independently predict the development of some cardiovascular risk factors such as hypertension and metabolic syndrome, as well as myocardial infarction and stroke. The relations between serum uric acid and established cardiovascular risk factors are complex, and these latter could be considered as confounding factors. In this report, we review the inextricably link of serum uric acid to known cardiovascular risk factors, and we describe the possible mechanisms and potential causative role between serum uric acid and cardiovascular events in the general population, in subjects with cardiovascular risk factors and in those with pre-existing cardiovascular diseases. Limited information however is available concerning the impact of urate-lowering treatments on cardiovascular events, whereas only a positive therapeutic trial could give definite answers to the difficult problem of causality of uric acid in relation to cardiovascular risk. Thus, it is time to propose the design of a therapeutic trial, integrating cardiologists and rheumatologists, in order to further decrease cardiovascular risk.
Transient visual symptoms (TVS) are common complaints. They can be related to transient ischemic attacks, but the nature of the symptoms often remains uncertain, and data on prognosis are scarce. We ...studied the prevalence, presentation, and effect of different types of TVS, paying particular attention to the association with high-risk pathology of embolism.
A total of 2398 patients with suspected transient ischemic attack admitted to the SOS-TIA clinic between January 2003 and December 2008 underwent immediate evaluation and treatment.
Eight hundred twenty-six (34.5%) patients had TVS, including 422 (17.6%) patients with isolated TVS. Transient monocular blindness was the most frequent TVS (36.3%), followed by diplopia (13.4%), homonymous lateral hemianopia (12.3%), bilateral positive visual phenomena (10.8%), and lone bilateral blindness (4.5%). Positive diffusion-weighted imaging was found in 11.8%, 8.1%, 8.1%, and 5.0% of patients with homonymous lateral hemianopia, diplopia, lone bilateral blindness, and transient monocular blindness, respectively. Among 1850 patients (595 patients with TVS) with definite/possible transient ischemic attack or minor stroke, a major source of embolism of cardiac or arterial origin was found less frequently in patients with isolated or nonisolated TVS than in patients without TVS (19.6%; 19.7% versus 28.1%, respectively; P<0.001). However, we found a higher rate of atrial fibrillation in patients with homonymous lateral hemianopia (23.2%) than in patients with other TVS (4.0%; adjusted odds ratio, 6.71; 95% confidence interval, 2.99-15.06) or nonvisual symptoms (9.1%; adjusted odds ratio, 4.39; 95% confidence interval, 2.26-8.50).
Approximately 20% of patients with TVS had a major source of embolism detected, requiring urgent management. Atrial fibrillation was particularly frequent in patients with transient homonymous lateral hemianopia.
Mechanical thrombectomy (MT) has become the cornerstone of acute ischemic stroke management in patients with large vessel occlusion (LVO). The aim of this guideline document is to assist physicians ...in their clinical decisions with regard to MT.
These guidelines were developed based on the standard operating procedure of the European Stroke Organisation, and followed the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach. An interdisciplinary working group identified 15 relevant questions, performed systematic reviews and meta-analyses of the literature, assessed the quality of the available evidence, and wrote evidence based recommendations. Expert opinion was provided if not enough evidence was available to provide recommendations based on the GRADE approach.
We found high quality evidence to recommend MT plus best medical management (BMM, including intravenous thrombolysis whenever indicated) to improve functional outcome in patients with LVO related acute ischemic stroke within 6 hours after symptom onset. We found moderate quality of evidence to recommend MT plus BMM in the 6-24 hour time window in patients meeting the eligibility criteria of published randomized trials. These guidelines further detail aspects of prehospital management, patient selection based on clinical and imaging characteristics, and treatment modalities.
MT is the standard of care in patients with LVO related acute stroke. Appropriate patient selection and timely reperfusion are crucial. Further randomized trials are needed to inform clinical decision making with regard to the mothership and drip-and-ship approaches, anesthaesia modalities during MT, and to determine whether MT is beneficial in patients with low stroke severity or large infarct volume.
Background
Mechanical thrombectomy (MT) has become the cornerstone of acute ischaemic stroke management in patients with large vessel occlusion (LVO). The aim of this guideline document is to assist ...physicians in their clinical decisions with regard to MT.
Methods
These Guidelines were developed based on the standard operating procedure of the European Stroke Organisation and followed the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach. An interdisciplinary working group identified 15 relevant questions, performed systematic reviews and meta-analyses of the literature, assessed the quality of the available evidence, and wrote evidence based recommendations. Expert opinion was provided if not enough evidence was available to provide recommendations based on the GRADE approach.
Results
We found high quality evidence to recommend MT plus best medical management (BMM, including intravenous thrombolysis whenever indicated) to improve functional outcome in patients with LVO-related acute ischaemic stroke within 6 hours after symptom onset. We found moderate quality of evidence to recommend MT plus BMM in the 6-24h time window in patients meeting the eligibility criteria of published randomized trials. These guidelines further detail aspects of prehospital management, patient selection based on clinical and imaging characteristics, and treatment modalities.
Conclusions
MT is the standard of care in patients with LVO-related acute stroke. Appropriate patient selection and timely reperfusion are crucial. Further randomized trials are needed to inform clinical decision making with regard to the mothership and drip-and-ship approaches, anesthaesia modalities during MT, and to determine whether MT is beneficial in patients with low stroke severity or large infarct volume.
Reperfusion therapies are the mainstay of acute ischemic stroke (AIS) treatments and overall improve functional outcome. Among the established complications of intravenous (IV) tissue-type ...plasminogen activator (tPA), intracranial hemorrhage (ICH) is by far the most feared and has been extensively described by seminal works over the last two decades. Indeed, IV tPA is associated with increased odds of any ICH and symptomatic ICH responsible for increased mortality rate during the first week after an AIS. Despite these results, IV tPA has been found beneficial in several pioneering randomized trials and improves functional outcome at 3 months. Endovascular therapy (EVT) combined with IV tPA for AIS patients consecutive to an anterior circulation large-vessel occlusion does not increase ICH occurrence. Of note, EVT following IV tPA leads to significantly higher rates of early reperfusion than with IV tPA alone, with no difference in ICH, which challenges the paradigm of reperfusion as a major prognostic factor for ICH complications. However, several blood biomarkers (glycemia, platelet and neutrophil count), clinical factors (age, AIS severity, blood pressure management, diabetes mellitus), and neuroradiological factors (cerebral microbleeds, infarct size) have been identified as risk factors for ICH after reperfusion therapy. In the years to come, the ultimate goal will be to further improve either reperfusion rates and functional outcome, while reducing hemorrhagic complications. To this end, various approaches being investigated are discussed in this review, such as blood-pressure control after reperfusion or the use of new antiplatelet agents as an adjunct to IV tPA and exhibit reduced hemorrhagic potential during the early phase of AIS.
Neutrophil Extracellular Traps (NETs) are DNA extracellular networks decorated with histones and granular proteins produced by activated neutrophils. NETs have been identified as major triggers and ...structural factors of thrombosis. A recent study designated extracellular DNA threads from NETs as a potential therapeutic target for improving tissue-type plasminogen activator (tPA)-induced thrombolysis in acute coronary syndrome. The aim of this study was to assess the presence of NETs in thrombi retrieved during endovascular therapy in patients with acute ischemic stroke (AIS) and their impact on tPA-induced thrombolysis.
We analyzed thrombi from 108 AIS patients treated with endovascular therapy. Thrombi were characterized by hematoxylin/eosin staining, immunostaining, and ex vivo enzymatic assay. Additionally, we assessed ex vivo the impact of deoxyribonuclease 1 (DNAse 1) on thrombolysis of AIS thrombi.
Histological analysis revealed that NETs contributed to the composition of all AIS thrombi especially in their outer layers. Quantitative measurement of thrombus NETs content was not associated with clinical outcome or AIS pathogenesis but correlated significantly with endovascular therapy procedure length and device number of passes. Ex vivo, recombinant DNAse 1 accelerated tPA-induced thrombolysis, whereas DNAse 1 alone was ineffective.
This study suggests that thrombus NETs content may be responsible for reperfusion resistance, including mechanical or pharmacological approaches with intravenous tPA, irrespectively of their etiology. The efficacy of a strategy involving an administration of DNAse 1 in addition to tPA should be explored in the setting of AIS.
URL: http://www.clinicaltrials.gov. Unique identifier: NCT02907736.
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