Acute Ischemic Stroke Thrombi Research Articles

Susceptibility weighted imaging for detection of thrombus in acute ischemic stroke: A cross-sectional study.

Susceptibility-weighted imaging (SWI) can help in the diagnosis of thrombus within the vessel in acute ischemic stroke, known as susceptibility vessel sign (SVS), and detection of SVS within the vessel can predict treatment modality and outcome. In this study, the purpose is to correlate the SVS on SWI with different parameters of stroke. This prospective cross-sectional study enrolled consecutive stroke patients with vessel occlusion on magnetic resonance angiography (MRA) over 1 year. The relationship between SVS on SWI with risk factors, territory involved, and length of thrombus was correlated with the National Institutes of Health Stroke Scale (NIHSS). A total of 105patients were enrolled in this study. Sixty-two percent (66 out of 105) of patients showed SVS on SWI with MRA-positive occlusion. A positive correlation was observed between SVS on SWI and the risk factor (p = 0.003, chi-square test), with 86% of patients with heart disease and 47% with hypertension exhibiting SVS. Additionally, a positive correlation was observed between SVS on SWI and territorial occlusion (p = 0.000, chi-square test). A moderate positive correlation was observed between the NIHSS and thrombus length (p = 0.002, Pearson's correlation coefficient), with a Pearson's coefficient of 0.367. SWI can be useful in identifying the location of the thrombus, and NIHSS can determine the thrombus length in acute stroke. A higher incidence of SVS can be associated with risk factors, and it also depends upon the site of occlusion of the vessel.

Extended Computed Tomography Angiography for the Successful Diagnosis of Cardioaortic Thrombus in Acute Ischemic Stroke and TIA: Study Protocol for a Randomized Controlled Trial.

Cardiac imaging is one of the main components of the etiological investigation of ischemic strokes. However, basic and advanced cardiac imaging remain underused in most stroke centers globally. Computed tomography angiography (CTA) of the supra-aortic and intracranial arteries is the most frequent imaging modality applied during the evaluation of patients with acute ischemic stroke to identify the presence of a large vessel occlusion. Recent evidence from retrospective observational studies has shown a high detection of cardiac thrombi, ranging from 6.6 to 17.4%, by extending a CTA a few cm below the carina to capture cardiac images. However, this approach has never been prospectively compared against usual care in a randomized controlled trial. The Extended Computed Tomography Angiography for the Successful Screening of Cardioaortic Thrombus in Acute Ischemic Stroke and TIA (DAYLIGHT) prospective, randomized, controlled trial evaluates whether an extended CTA (eCTA) + standard-of-care stroke workup results in higher detection rates of cardiac and aortic source of embolism compared to standard-of-care CTA (sCTA) + standard-of-care stroke workup. DAYLIGHT is a single-center, prospective, randomized, open-blinded endpoint trial, aiming to recruit 830 patients with suspected acute ischemic stroke or transient ischemic attack (TIA) being assessed under acute code stroke at the emergency department or at a dedicated urgent stroke prevention clinic. Patients are randomized 1:1 to eCTA versus sCTA. The eCTA expands image acquisition caudally, 6 cm below the carina. All patients receive standard-of-care cardiac imaging and diagnostic stroke workup. The primary efficacy endpoint is the diagnosis of a cardioaortic thrombus after at least 30 days of follow-up. The primary safety endpoint is door-to-CTA completion time. The diagnosis of a qualifying ischemic stroke or TIA is independently adjudicated by a stroke neurologist, blinded to the study arm allocation. Patients without an adjudicated ischemic stroke or TIA are excluded from the analysis. The primary outcome events are adjudicated by a board-certified radiologist with subspecialty training in cardiothoracic radiology and a cardiologist with formal training in cardiac imaging. The primary analysis is performed according to the modified intention-to-diagnose principle and without adjustment by logistic regression models. Results are presented with odds ratios and 95% confidence intervals. The DAYLIGHT trial will provide evidence on whether extending a CTA to include the heart results in an increased detection of cardioaortic thrombi compared to standard-of-care stroke workup.

Safety and efficacy of N-acetylcysteine (NAC) as an adjunct to standard treatment in patients with acute ischemic stroke: a randomized controlled pilot trial (NACTLYS)

There is a pressing clinical need for thrombolytic agents that can effectively disaggregate arterial thrombi in acute ischemic stroke without significantly increasing the risk of bleeding. This pilot study aimed to investigate the safety and efficacy of N-acetylcysteine (NAC) as an adjunctive therapy to intravenous recombinant tissue plasminogen activator (rtPA or alteplase). A randomized, open-label, blinded assessor pilot study was conducted. Patients presenting with an acute ischemic stroke within 4.5 h from onset were randomized into two groups: intravenous NAC and rtPA or rtPA alone. Primary outcomes included intracerebral hemorrhage, symptomatic intracerebral hemorrhage, extracranial bleeding, and adverse reactions. Secondary outcomes comprised major neurological improvement assessed by (National Institute of Health Stroke Scale) NIHSS at 24 h, recanalization on first run of angiography in patients who underwent thrombectomy or on repeat vascular imaging at 24 h, modified Rankin scale, and three-month mortality. Forty patients were enrolled, with 21 receiving only rtPA and 19 receiving NAC with rtPA. Baseline characteristics were comparable among groups. No significant differences were observed in adverse events (p = 0.99), intracranial hemorrhage (p = 0.21), symptomatic intracerebral hemorrhage (p = 0.47), or extracranial bleeding (p = 0.21). Median NIHSS at 24 h was significantly lower in the intervention group (p = 0.03). Functional outcomes and three-month mortality were similar between groups (p = 0.85 and p = 0.99 respectively). The co-administration of N-acetylcysteine with alteplase did not significantly alter safety profiles, morbidity, or mortality at 3 months. While no substantial differences were noted, a slightly improved early neurological outcome was observed in the intervention arm. The study's findings were constrained by a small sample size, emphasizing the necessity for future large-scale trials to comprehensively evaluate the safety and efficacy of N-acetylcysteine as a thrombolytic agent in acute ischemic stroke.Trial Registration Clinical Trials Registry India—CTRI/2019/05/019305.

Label-free histological analysis of retrieved thrombi in acute ischemic stroke using optical diffraction tomography and deep learning.

For patients with acute ischemic stroke, histological quantification of thrombus composition provides evidence for determining appropriate treatment. However, the traditional manual segmentation of stained thrombi is laborious and inconsistent. In this study, we propose a label-free method that combines optical diffraction tomography (ODT) and deep learning (DL) to automate the histological quantification process. The DL model classifies ODT image patches with 95% accuracy, and the collective prediction generates a whole-slide map of red blood cells and fibrin. The resulting whole-slide composition displays an average error of 1.1% and does not experience staining variability, facilitating faster analysis with reduced labor. The present approach will enable rapid and quantitative evaluation of blood clot composition, expediting the preclinical research and diagnosis of cardiovascular diseases.

Neutrophil Extracellular Traps in Ischemic Stroke Thrombi Are Associated Wth Poor Clinical Outcome

Background Acute ischemic stroke is a neurologic emergency associated with severe disability and death. There is growing evidence that neutrophil extracellular traps (NETs) contribute to the pathogenesis of acute stroke. By mechanical removal of the occluding thrombus from the patient's vasculature, endovascular thrombectomy enables the collection of thrombus material for immunohistologic analysis. The aim of our study was to strengthen the association of NET content in ischemic thrombi with clinical outcome and guide future therapeutics. Methods We performed an immunohistologic analysis of thrombi from 101 patients with acute ischemic stroke, focusing on the association between NET content and clinical and interventional indicators. Results NETs were present in every patient with acute ischemic stroke. Their abundance in thrombi was associated with interventional markers of thrombus stability. NET‐rich thrombi were associated with unsuccessful recanalization (modified Thrombolysis in Cerebral Infarction <2B) and longer procedure time, and NET abundance in acute ischemic stroke thrombi was associated with outcomes evaluated by patients’ postassessment National Institutes of Health Stroke Scale and modified Rankin Scale scores. Conclusion These findings suggest that NET content is critically important to thrombus stability and clinical outcome in acute stroke. They should open new perspectives for innovative immunotherapy strategies based on neutrophil modulation.

Abstract Number ‐ 175: First Pass Results of Mechanical Thrombectomy with two‐drop zone NeVaTM Device

Introduction Occlusive thrombi in acute ischemic stroke can be in various types which limits the success of the thrombectomy.The NeVaTM(Vesalio, Nashville, Tennessee) thrombectomy device was originally designed for all types of clot. Our aim was to evaluate the efficacy and safety of the NeVaTMdevice for mechanical thrombectomy. Methods Retrospective review of prospectively collected mechanical thrombectomy database revealed 145 patients who had fullfilled the inclusion criteria.The data collected includes clinical patient characteristics, procedural measures, timestamp at each stage, and patient outcome. IV thrombolytics application, pre and post‐intervention imaging findings, device related adverse event and any type of intracranial hemorrhage were recorded. Results There was female pre‐dominance (54.5%). Median presenting NIHSS was 16 (IQR, 3–32). 88 MCA‐m1 (60,6%), 43 ICA‐tip (29,6%), 11 MCA‐m2 (7,5%), 2 ACA (1,4%) and 1 basilar (0,7%) occlusions were underwent for mechanical thrombectomy. Median procedure time was 25 min (IQR, 7–136). First‐pass reperfusion scores were mTICI 0–2a 22.7%, mTICI 2b 23.4%, mTICI 2c 17.9% andmTICI 3 35.9%.Mean number of pass was1,84±1,14.Final mTICI 2b‐3 score was 97.9% and TICI2c‐3 score was 87.6%. No device related adverse event occurred. The mean 24‐hour NIHS score was 6 (IQR 0–33). Conclusions In conclusion, the NeVa thrombectomy device offers a high rate of first‐pass success along with favorable safety profile. Larger series and multi‐center studies are needed for further investigation

Factors related to white thrombi in acute ischemic stroke in cancer patients.

Thrombi in cerebral large vessel occlusion associated with active cancer are often fibrin and platelet-rich white thrombi. However, evaluating the thrombus composition in a short time before thrombectomy is often ineffective. We sought to determine factors related to white thrombi in acute ischemic stroke due to large vessel occlusion in cancer patients. Consecutive cancer patients undergoing thrombectomy for acute ischemic stroke due to large vessel occlusion between January 2018 and May 2022 were retrospectively reviewed. The patients were classified into white thrombus and red thrombus groups on the basis of the pathological findings of retrieved thrombi. Patient characteristics and laboratory findings were compared between the two groups. There were 12 patients in the white thrombus group and 11 patients in the red thrombus group. Active cancer was significantly more in the white thrombus group than in the red thrombus group (91.7% vs. 36.3%, p = 0.0094). Internal carotid artery occlusion was significantly less in the white thrombus group than in the red thrombus group (0% vs. 36.4%, p = 0.037). Among laboratory findings, D-dimer levels were an independent factor associated with white thrombi (odds ratio 8.97 [95% confidence interval 1.71-368.99], p < 0.0001). The cutoff value of D-dimer levels for predicting white thrombi was 3.5μg/mL (83.3% sensitivity and 100% specificity). In acute ischemic stroke in cancer patients, active cancer, no internal carotid artery occlusion, and higher D-dimer levels (≥3.5μg/mL) may be associated with occlusion with fibrin and platelet-rich white thrombi.

Utility of dual energy CT in differentiating clot in acute ischemic stroke.

Red blood cells (RBC)-poor thrombi in acute ischemic stroke (AIS) are associated with longer recanalization time for mechanical thrombectomy than RBC-rich thrombi. The purpose of the study was to differentiate between RBC-rich and RBC-poor thrombi using dual energy computed tomography (DECT). This retrospective study was conducted on patients with acute arterial occlusion of anterior circulation who underwent DECT cerebral angiography, followed by mechanical thrombectomy with the pathological diagnosis of thrombi, dividing into RBC-rich and RBC-poor thrombi. The CT attenuation values and thrombus enhancement were measured in non-contrast scans and CTA phases at different energy levels and compared between RBC-rich and RBC-poor groups. Fourteen acute stroke patients were included in the study. There were 7 patients in RBC-rich group and 7 patients in RBC-poor group. The CT attenuation values of RBC-rich thrombi were significantly higher than those of RBC-poor thrombi at energy levels of 40, 50, 60, 70, and 80KeV, with the most significant difference at 80KeV (p = 0.032). A cutoff value of 44.1 Hounsfield units (HU) on 80keV monoenergetic reconstructions was used to distinguish between RBC-rich and RBC-poor thrombi. It achieved an area under the curve (AUC) of 0.878, sensitivity of 85.7%, specificity of 100%, and accuracy of 92.9%. The degree of enhancement was higher in RBC-poor thrombi than in RBC-rich thrombi, without statistically significant difference. DECT could help differentiate between RBC-rich and RBC-poor thrombi by using CT attenuation values in non-contrast phase at lower energy levels (40-80KeV).

Machine Learning Analysis of the Cerebrovascular Thrombi Lipidome in Acute Ischemic Stroke.

OBJECTIVE: The aim of this study was to identify a signature lipid profile from cerebral thrombi in acute ischemic stroke (AIS) patients at the time of ictus. METHODS: We performed untargeted lipidomics analysis using liquid chromatography-mass spectrometry on cerebral thrombi taken from a nonprobability, convenience sampling of adult subjects (≥18 years old, n = 5) who underwent thrombectomy for acute cerebrovascular occlusion. The data were classified using random forest, a machine learning algorithm. RESULTS: The top 10 metabolites identified from the random forest analysis were of the glycerophospholipid species and fatty acids. CONCLUSION: Preliminary analysis demonstrates feasibility of identification of lipid metabolomic profiling in cerebral thrombi retrieved from AIS patients. Recent advances in omic methodologies enable lipidomic profiling, which may provide insight into the cellular metabolic pathophysiology caused by AIS. Understanding of lipidomic changes in AIS may illuminate specific metabolite and lipid pathways involved and further the potential to develop personalized preventive strategies.

First pass results of mechanical thrombectomy with two-drop zone NeVaTM device.

Occlusive thrombi in acute ischemic stroke can be in various types which limits the success of the thrombectomy. The NeVaTM (Vesalio, Nashville, Tennessee) thrombectomy device was originally designed for all types of clot. Our aim was to evaluate the efficacy and safety of the NeVaTM device for mechanical thrombectomy. Retrospective review of prospectively collected mechanical thrombectomy database revealed 145 patients who had fullfilled the inclusion criteria. The data collected includes clinical patient characteristics, procedural measures, timestamp at each stage, and patient outcome. IV thrombolytics application, pre and post-intervention imaging findings, device related adverse event and any type of intracranial hemorrhage were recorded. There was female pre-dominance (54.5%). Median presenting national institutes of health stroke scale (NIHSS) was 16 (IQR, 3-32). 88 MCA-m1 (60,6%), 43 ICA-tip (29,6%), 11 MCA-m2 (7,5%), 2 ACA (1,4%) and 1 basilar (0,7%) occlusions were underwent for mechanical thrombectomy. Median procedure time was 25 min (IQR, 7-136). First-pass reperfusion scores were mTICI 0-2a 22.7%, mTICI 2b 23.4%, mTICI 2c 17.9% and mTICI 3 35.9%. Mean number of pass was 1,84 ± 1,14. Final mTICI 2b-3 score was 97.9% and TICI2c-3 score was 87.6%. No device related adverse event occurred. The mean 24-h NIHSS score was 6 (IQR 0-33). In conclusion, the NeVa thrombectomy device offers a high rate of first-pass success along with favorable safety profile. Larger series and multi-center studies are needed for further investigation.

High thrombus platelet content is associated with a lower rate of first pass effect in stroke treated by endovascular therapy.

First pass effect (FPE), the occurrence of complete reperfusion after one pass with no rescue attempt during endovascular therapy (EVT), is associated with the best clinical outcome after an acute ischemic stroke (AIS). Previous studies evaluating FPE occurrence according to EVT technical strategies, occlusion locations, or thrombus composition have provided controversial results. Here, we performed a correlation analysis between FPE occurrence and AIS thrombus cellular composition, as assessed using quantitative biochemical assays. Homogenates of AIS thrombi from 250 patients were prepared by mechanical grinding. Platelet, red blood cell (RBC), and leukocyte contents of AIS thrombi were respectively estimated by quantification of GP (glycoprotein) VI, heme, and DNA in thrombus homogenates. FPE was defined as a modified Thrombolysis in Cerebral Infraction (mTICI) score of 2C or 3 after a single EVT device pass. AIS thrombi successfully removed after a single pass were poorer in GPVI (0.098 ± 0.023 vs 0.111 ± 0.024 ng/mg, p < 0.001) compared to those whose removal had required several passes. GPVI content was also significantly associated with a higher number of device passes and a longer procedure time. No such significant correlation was found with DNA and heme content. Thrombus platelet content may hamper thrombus removal by EVT. This result suggests that adjunctive therapies or functionalization of retrieval devices targeting platelets may improve EVT efficacy.

Impact of COVID‐19 on thrombus composition and response to thrombolysis: Insights from a monocentric cohort population of COVID‐19 patients with acute ischemic stroke

BackgroundResistance to fibrinolysis, levels of procoagulant/antifibrinolytic neutrophil extracellular traps (NETs), and the severity of acute ischemic stroke (AIS) are increased by COVID‐19. Whether NETs are components of AIS thrombi from COVID‐19 patients and whether COVID‐19 impacts the susceptibility of these thrombi to thrombolytic treatments remain unknown, however. ObjectivesWe aimed to characterize AIS thrombi from COVID‐19 patients by immunohistology and to compare their response to thrombolysis to that of AIS thrombi from non‐COVID‐19 patients. Patients/MethodsFor this monocentric cohort study, 14 thrombi from COVID‐19 AIS patients and 16 thrombi from non‐COVID‐19 patients, all recovered by endovascular therapy, were analyzed by immunohistology or subjected to ex vivo thrombolysis by tissue‐type plasminogen (tPA)/plasminogen. ResultsCOVID‐19 AIS thrombi were rich in neutrophils and contained NETs, but not spike protein. Thrombolysis assays revealed a mean resistance profile to tPA/plasminogen of COVID‐19 AIS thrombi similar to that of non‐COVID‐19 AIS thrombi. The addition of DNase 1 successfully improved thrombolysis by potentiating fibrinolysis irrespective of COVID‐19 status. Levels of neutrophil, NETs, and platelet markers in lysis supernatants were comparable between AIS thrombi from non‐COVID‐19 and COVID‐19 patients. ConclusionsThese results show that COVID‐19 does not impact NETs content or worsen fibrinolysis resistance of AIS thrombi, a therapeutic hurdle that could be overcome by DNase 1 even in the context of SARS‐CoV‐2 infection.

Histological analysis of thrombi retrieved after acute ischemic stroke from large vessel occlusion: from research to clinical practice

Emergent reperfusion therapies have improved acute ischemic stroke prognosis, but many patients are still bound to bad clinical outcome, probably because of our incomplete knowledge of its pathophysiology. Thanks to mechanical thrombectomy, occluding material is available for histological analysis. Several studies investigated the possible relationship between thrombus composition and clinical, procedural, and radiological variables of acute ischemic stroke. The potential value of thrombus analysis as a tool for clinical practice and research is still not defined, as data from the literature are heterogeneous and sometimes conflicting. We propose a review of the existing literature regarding histological analysis of thrombi in acute ischemic stroke. We classified articles on clot composition according to the clinical variable explored in each study. We first distinguished articles about etiology, procedural, and radiological variables, and then we performed a subclassification for each group. This review could help both in the interpretation of thrombus analysis in clinical practice and in its usage for future research.

Therapeutic dilemma: When to start anticoagulation for cardiac thrombi in acute ischemic stroke? Lessons from cases

Ischemic stroke has been one of the major reason for morbidity and mortality all over the world. Anticoagulation treatment in patients with cerebral ischemic events caused by cardiac emboli is no longer a matter of debate. The problem is when to start. Because of a recurrence rate of 15 to 20% in the first few weeks after the initial event, direct anticoagulation by means of intravenous heparin followed by oral anticoagulants seems to be indicated. We are presenting 2 cases of patients who suffered cardio-embolic stroke due to cardiac thrombosis and had a therapeutic dilemma on when to start the anticoagulation treatment. Early anticoagulation treatment was associated with good clinical and neurological outcome. Keywords: anticoagulation; stroke; cardiac thrombus; cardio-embolic stroke; hemorrhagic stroke; warfarin.

Thrombus Composition, Imaging, and Outcome Prediction in Acute Ischemic Stroke

New imaging techniques have advanced our ability to capture thrombus characteristics and burden in real time. An improved understanding of recanalization rates with thrombolysis and endovascular thrombectomy based on thrombus characteristics has spurred interest in new therapies for acute stroke. This article reviews the biochemical, structural, and imaging characteristics of intracranial thrombi in acute ischemic stroke; the relationship between thrombus composition and response to lytic and endovascular therapies; and current and future directions for improving outcomes in patients with acute stroke based on thrombus characteristics. Thrombus composition, size, location, and timing from stroke onset correlate with imaging findings in acute ischemic stroke and are associated with clinical outcome. Further research across multiple domains could assist in better applying our knowledge of thrombi to patient selection and individualization of acute therapies.

Value of susceptibility weighted imaging (SWI) in assessment of intra-arterial thrombus in patients with acute ischemic stroke

BackgroundIschemic stroke is a major cause of death and disability. Thrombolytic therapy is a standard treatment stroke nowadays for ischemic strokes up to 4.5 h from start of symptoms. Although arterial occlusion can be detected by digital subtraction angiography (DSA), magnetic resonance angiography (MRA), and computed tomography angiography (CTA), the question about thrombus composition and formation times still might not be replied. The use of susceptibility weighted imaging (SWI) for detecting thrombus in acute ischemic stroke is getting to be a strongly investigated field. SWI can show the thrombus as a hypointense susceptibility vessel sign (SVS) in the affected area.ResultsNinety-seven of our patients showed thrombus in MRA study. M1 segment was the most affected MCA segment representing about 57.6%. SWI detected intra-arterial thrombus in 122 patients compared to 97 patients detected by MRA (P = 0.0002). All patients had positive susceptibility sign. 88.8% of patients with positive thrombus in SWI had solitary thrombus, and 11.2% has multiple thrombi; on the other hand, MRA fails to detect any distant thrombi. 81% of patients with abnormally prominent vessel sign (APVS) showed parenchymal changes in these areas. On the other hand, deep structures, namely caudate nucleus, internal capsule and lentiform nucleus, are the least affected areas. All patients with abnormally prominent vessel sign showed arterial occlusion, and only 9 patients with no APVS showed arterial occlusion (P = 0.0001).ConclusionSWI plays an important role in the detection of peripheral thrombi in patients with acute ischemic stroke. Both SWI and MRA might complement each other for visual detection of occluded vessel. We recommend implementation of SWI into routine acute stroke MRI protocols.

Endovascular Treatment Effect Diminishes With Increasing Thrombus Perviousness: Pooled Data From 7 Trials on Acute Ischemic Stroke.

Thrombus perviousness estimates residual flow along a thrombus in acute ischemic stroke, based on radiological images, and may influence the benefit of endovascular treatment for acute ischemic stroke. We aimed to investigate potential endovascular treatment (EVT) effect modification by thrombus perviousness. We included 443 patients with thin-slice imaging available, out of 1766 patients from the pooled HERMES (Highly Effective Reperfusion Evaluated in Multiple Endovascular Stroke trials) data set of 7 randomized trials on EVT in the early window (most within 8 hours). Control arm patients (n=233) received intravenous alteplase if eligible (212/233; 91%). Intervention arm patients (n=210) received additional EVT (prior alteplase in 178/210; 85%). Perviousness was quantified by thrombus attenuation increase on admission computed tomography angiography compared with noncontrast computed tomography. Multivariable regression analyses were performed including multiplicative interaction terms between thrombus attenuation increase and treatment allocation. In case of significant interaction, subgroup analyses by treatment arm were performed. Our primary outcome was 90-day functional outcome (modified Rankin Scale score), resulting in an adjusted common odds ratio for a one-step shift towards improved outcome. Secondary outcomes were mortality, successful reperfusion (extended Thrombolysis in Cerebral Infarction score, 2B–3), and follow-up infarct volume (in mL). Increased perviousness was associated with improved functional outcome. After adding a multiplicative term of thrombus attenuation increase and treatment allocation, model fit improved significantly (P=0.03), indicating interaction between perviousness and EVT benefit. Control arm patients showed significantly better outcomes with increased perviousness (adjusted common odds ratio, 1.2 [95% CI, 1.1–1.3]). In the EVT arm, no significant association was found (adjusted common odds ratio, 1.0 [95% CI, 0.9–1.1]), and perviousness was not significantly associated with successful reperfusion. Follow-up infarct volume (12% [95% CI, 7.0–17] per 5 Hounsfield units) and chance of mortality (adjusted odds ratio, 0.83 [95% CI, 0.70–0.97]) decreased with higher thrombus attenuation increase in the overall population, without significant treatment interaction. Our study suggests that the benefit of best medical care including alteplase, compared with additional EVT, increases in patients with more pervious thrombi.

Abstract P401: Subocclusive and Occlusive Intracranial Thrombi in Acute Ischemic Stroke

Background: Non-occlusive thrombus in an intracranial artery in acute ischemic stroke is an uncommon occurrence. We compared the clinical course and outcome of intracranial subocclusive to occlusive thrombi. Methods: We conducted a review of patients who presented with acute ischemic stroke and received CT angiogram at a single comprehensive stroke center from January 2018 to December 2019. Patients with intracranial subocclusive thrombus were compared to a control group with complete occlusion matched for occlusion location. Subocclusive thrombus was reviewed by two raters on CT angiography, disagreement resolved by consensus. Patient and stroke characteristics and the clinical course were analyzed. Neurological deterioration was defined as an increase in NIH Stroke Scale (NIHSS) score &gt; 4 compared from baseline to 48 hours. Good outcome at discharge was defined as modified Rankin Score of ≤2. Results: Among 1151 acute ischemic strokes, there were 896 patients with CT angiograms. Sixteen out of 896 (1.8%) patients had intracranial subocclusive thrombus. Thirty-two with comparable intracranial occlusions were identified. In the subocclusive group, 3 of 16 (19%) of received acute endovascular intervention, compared to 13 of 32 (41%) in the occluded group. Sex, median age or time from last known well to hospital arrival did not differ between the two groups. The subocclusive thrombus group had less severe strokes, with median NIHSS score at arrival 3 compared to 8.5 in the occlusion group (p&lt;0.01) and median NIHSS at discharge 1 compared to 5.5 in the occlusive group (p&lt;0.01). Frequency of neurological deterioration in hospital did not differ between the subocclusive and occluded groups at 48 hours (15% vs 15% p=1.00). The subocclusive group was associated with a good outcome at discharge, OR 0.5.71, 95% confidence interval 1.41-23.1. Conclusion: Intracranial subocclusive thrombus in acute ischemic stroke has a more mild presentation compared to complete intracranial occlusion without a high rate of neurological deterioration.

The Role of Neutrophil Extracellular Traps in Central Nervous System Diseases and Prospects for Clinical Application

Neutrophil extracellular traps (NETs) are complexes of decondensed DNA fibers and antimicrobial peptides that are released by neutrophils and play important roles in many noninfectious diseases, such as cystic fibrosis, systemic lupus erythematosus, diabetes, and cancer. Recently, the formation of NETs has been detected in many central nervous system diseases and is thought to play different roles in the occurrence and development of these diseases. Researchers have detected NETs in acute ischemic stroke thrombi, and these NETs are thought to promote coagulation and thrombosis. NETs in ischemic brain parenchyma were identified as the cause of secondary nerve damage. High levels of NETs were also detected in grade IV glioma tissues, where NETs were involved in the proliferation and invasion of glioma cells by activating a signaling pathway. Extracellular web-like structures have also recently been observed in mice with traumatic brain injury (TBI), and it was hypothesized that NETs contribute to the development of edema after TBI. This article reviews the effect of NETs on multiple diseases that affect the CNS and explores their clinical application prospects.

Predictors of left atrial thrombus in acute ischemic stroke patients without atrial fibrillation: A single-center cross-sectional study.

The present study aimed to determine independent predictors of left atrial thrombus (LAT) in acute ischemic stroke (AIS) patients without atrial fibrillation (AF) using transesophageal echocardiography (TEE). In this single-center, retrospective study, we enrolled 149 consecutive AIS patients. All of the patients underwent a TEE examination to detect LAT within 10 days following admission. Multivariate logistic regression analysis was performed to assess independent predictors of LAT. Among all cases, 14 patients (9.3%) had a diagnosis of LAT based on the TEE examination. In a multivariate analysis, elevated mean platelet volume (MPV), low left-ventricle ejection fraction (EF), creatinine, and reduced left-atrium appendix (LAA) peak emptying velocity were independent predictors of LAT. The area under the receiver operating characteristic curve analysis for MPV was 0.70 (95%CI: 0.57-0.83; p = 0.011). With the optimal cut-off value of 9.45, MPV had a sensitivity of 71.4% and a specificity of 63% to predict LAT. AIS patients with low ventricle EF and elevated MPV should undergo further TEE examination to verify the possibility of a cardio-embolic source. In addition, this research may provide novel information with respect to the applicability of MPV to predict LAT in such patients without AF.