Acute Ischemic Stroke Patients Research Articles

Abstract 10: Does the use of CT perfusion (CTP) increase treatment rate of endovascular thrombectomy (EVT) in acute ischemic stroke patients?

Introduction: CTP is used to distinguish core infarct from penumbral tissue in the 6-24 hour time window from last known well time (LKW). In addition, routine use of CTP inside of 6 hours may increase the sensitivity of detecting medium vessel occlusion (MeVO) as compared with CTA alone. Therefore, some centers apply a strategy of using CTP/CTA routinely in the first 6 hours from LKW while others reserve CTP for the 6-24 hour delayed time window. We hypothesized that use of CTP/CTA inside of 6 hours from LKW is associated with increased EVT especially for MeVO. Methods: This is a retrospective analysis of acute ischemic stroke (AIS) patients from a multi-state stroke registry between Jan 2018 and Mar 2024 who presented within 6 hours of LKW. The incidence of EVT by triage imaging modality (CTA or CTA/CTP) was analyzed overall and also by occlusion location (Large vessel occlusion (LVO), MeVO) through linear mixed models (LMM). Multivariable models were used to adjust for confounding factors. A two-tailed p value of <0.05 was considered statistically significant. Statistical analyses were performed using the statistical software R (version 4.2.3). Results: Of the 13,778 AIS patients analyzed, 43% were triaged with CTP/CTA and CTA alone was used for 57%. The unadjusted EVT treatment rate was 9.8% in patients triaged with CTA alone and 22% for patients triaged with CTP/CTA. LMMs adjusted for age at diagnosis, sex, race and ethnicity, NIHSS at admit and comorbidities show a higher statistically significant likelihood of receiving EVT in the CTA/CTP triaged patients (OR 1.6, 95%CI 1.3 to 1.8, p <0.001). For LVO, there was no difference in the likelihood of receiving EVT in the CTA/CTP triaged patients (OR 1.3, 95%CI 0.7 to 2.3, p = .4). However, for MeVO there was a higher likelihood of receiving EVT in the CTA/CTP triaged patients (OR 3.2, 95%CI 2.0 to 5.0, p <0.001) ( Fig 1 ) Conclusions: The results here show that in a large system of stroke hospitals that AIS patients presenting within 6 hours of LKWT who received CTP/CTA were more likely to undergo EVT than those who received CTA alone. This increased utilization of EVT was accounted for by increased EVT for MEVO but not for LVO. The increased utilization of EVT in MEVO may reflect increased sensitivity of detecting MeVO with the addition of CTP. If MEVO EVT treatment proves effective in ongoing randomized clinical trials, our data argue for more routine use of CTP as a “MEVO detector” in the early time window.

Abstract TMP57: Cerebral Blood Reserve Predicts Early Neurological Deterioration in Minor Stroke with Large Vessel Occlusion or Severe Stenosis

Introduction: Literature demonstrates that nearly one-third of acute ischemic stroke (AIS) patients with large vessel occlusion (LVO) or severe stenosis arrive at the emergency room with mild symptoms, attributed to favourable collateral status. However, approximately 20~40% of patients with mild symptoms due to LVO or severe stenosis are at risk of early neurological deterioration (END) as a consequence of subsequent collateral failure post arrival. This study aimed to identify the difference of collateral patterns between mild stroke patients with END and those without. Methods: AIS patients presenting within 24 hours from last known well, with a baseline NIHSS≤5 and anterior circulation LVO or severe stenosis were included. Patients who underwent endovascular treatment before END were excluded. END was defined as an increase in total NIHSS≥4 or NIHSS≥2 for any item within 72 hours, without evidence of parenchymal hemorrhage. Collateral flow was rated as the Tan scale (leptomeningeal collaterals) and cerebral blood volume (CBV) index (cerebral blood flow reserve). A good leptomeningeal collateral score (goodCS) was defined as Tan scale≥2 (poorCS: Tan scale <2). CBVindex was calculated as the ratio of mean CBV within Tmax>6s lesion over the mean CBV of Tmax<4s area. Results: A total of 237 AIS patients with mild symptoms due to anterior circulation LVO or severe stenosis were included and END occurred in 22% of the patients. Stepwise logistic regression analysis revealed that higher CBVindex and poorCS were associated with the increased risk of END occurrence. The optimal threshold of CBVindex predicting END was 0.735 (sensitivity: 0.83; specificity:0.48). Accordingly, patients were divided into four groups: group1: CBVindex<0.735+ poorCS; group2: CBVindex<0.735+goodCS; group3: CBVindex>0.735+goodCS; group4: CBVindex>0.735+ poorCS. Further analysis showed that that patients with CBVindex>0.735 and poorCS (group 4) were most likely to present with END (logistic OR[95%CI]: 5.18[1.22,22.18] P=0.026). Conclusions: Higher CBVindex and poor leptomeningeal collaterals were independent predictors of END in patients with mild symptoms due to anterior circulation LVO or severe stenosis. Therefore, we hypothesize that though higher CBVindex reflects favorable collaterals at baseline, higher CBVindex combined with the absence of goodCS indicates insufficient blood flow reserve, leading to collapse of collateral flow during acute phase, therefore, the occurrence of END.

Abstract WP95: Impact of First Imaging Protocol Changes on Door-to-Puncture Time in Acute Ischemic Stroke Patients Undergoing Endovascular Thrombectomy

Introduction: The choice of initial imaging modality significantly impacts door-to-puncture time (DPT) in acute ischemic stroke (AIS) patients undergoing endovascular thrombectomy (EVT). Studies have shown that using CT as the first imaging modality can reduce DPT compared to MRI. In July 2023, we revised critical pathway (CP) protocols including first image modalities from MRI to CT regardless of last known normal time (LNT). Therefore, we evaluated the impact of process modification including first image modalities could reduce the DPT for the EVT candidates. Methods: Prior to July 2023, EVT candidate AIS patients who visited Seoul National University Bundang Hospital, comprehensive stroke center, received CT as the first imaging modality if they arrived within 6 hours after onset, while others underwent MRI. From July 2023, all patients with disabling symptoms or an NIHSS score of 6 or higher received CT as the initial imaging, irrespective of LNT. We retrospectively analyzed the single center quality indicators, including DPT, door-to-image time, door-to-reperfusion time, and proportion of symptomatic intracerebral hemorrhage (sICH) comparing outcomes before and after the protocol change. Results: The total number of AIS patients undergoing EVT increased from 396 in the first half of 2022 to 442 in the second half of 2023. Median DPT decreased from 71 minutes in early 2022 to 60 minutes after the protocol change, with a corresponding increase in the proportion of patients achieving DPT within 60 minutes from 37.5% to 52.2%. The median door-to-image time for patients receiving CT decreased from 27 minutes to 22.5 minutes, with 94% achieving imaging within 30 minutes post-change compared to 70% pre-change. MRI, on the other hand, showed a median door-to-image time reduction from 30 minutes to 28.5 minutes, but only 50% achieved imaging within 30 minutes. Overall, the median door-to-reperfusion time decreased from 130 minutes to 105 minutes, with the proportion of patients achieving reperfusion within 120 minutes increasing from 37.9% to 62.5%. There was no significant change in proportion of sICH. Conclusions: The protocol change to a CT-first approach significantly improved key EVT quality indicators, particularly in reducing door-to-puncture time. These findings underscore the importance of optimizing imaging strategies to enhance outcomes in AIS patients undergoing EVT.

Abstract TP163: Single- and Multi-Phase Computed Tomography Angiography Are Associated with Digital Subtraction Angiography and American Society of Interventional and Therapeutic Neuroradiology Collateral Score of Three or Greater

Introduction: Imaging features are increasingly relevant for predicting response to endovascular treatment in acute ischemic stroke (AIS) patients. Collateral status is a well-documented marker of reperfusion and mortality in patients with large vessel occlusion (LVO) anterior circulation strokes, which account for approximately one-third of AIS. There is ongoing investigation into optimal collateral status determination, with single and multiphase computed tomography angiography (mCTA) and CT perfusion parameters under consideration. To assess the utility of these parameters, we evaluated their association with the American Society of Interventional and Therapeutic Neuroradiology (ASITN) collateral score standard on digital subtraction angiography (DSA). Methods: We retrospectively evaluated AIS patients treated at our institution between January 2017 and January 2023. Inclusion criteria were: (i) CTA-confirmed anterior circulation LVO; (ii) diagnostic CT perfusion was performed; (iii) mechanical thrombectomy was attempted with documented DSA collateral score. Modified Treatment in Cerebral Ischemia (mTICI) score was used to determine reperfusion status, with mTICI > 2b considered successful. Univariate and multivariate logistic regression analyses were conducted to determine associations of demographic/clinical factors and collateral status with ASITN and reperfusion status. Results: A total of 311 patients (mean age 67.35 ± 16.37, 57.4% female) met inclusion criteria. On univariate analysis, PM2 occlusion site (p=9.78E-7), Alberta Stroke Programme Early CT Score (p=0.006), mCTA (p=1.82E-10), cortical vein opacification score (p=4.18E-7), and clot burden score (CBS, p=3.01E-13) were associated with ASITN score of three or greater, signifying complete collateral flow. On multivariate regression adjusted for race, occlusion site, radiologic features, and admission NIH stroke score, PM2 occlusion site (aOR 1.19, p=0.049), mCTA (aOR 3.59, p=6.03E-5), and CBS (aOR 1.37, p=0.03) were associated with ASITN ≥ 3 (Table 1). No radiologic features were associated with successful reperfusion (Table 2). Conclusion: Multiphase CTA and clot burden score show a stronger association with favorable DSA collateral scores than do CT perfusion parameters, including cerebral blood volume and hypoperfusion intensity ratio. Further studies are needed to evaluate these measures in outcome prediction to aid clinical decision-making for AIS patients with anterior circulation LVOs.

The prognostic role of iron deficiency in acute ischemic stroke patients: A prospective multicentric cohort study.

Iron deficiency (ID) is a prognostic factor in heart failure and acute coronary syndrome. However, its role in cerebrovascular diseases is controversial. We aimed to determine the impact of ID on the functional outcome of acute ischemic stroke patients. This was an observational prospective multicentric cohort study. From January to December 2023, we enrolled acute ischemic stroke patients admitted to the stroke units of four comprehensive stroke centers. Venous blood samples were collected at admission to determine the iron status (serum iron, ferritin, transferrin). ID was defined as a serum ferritin concentration<100ng/mL or 100-299ng/mL with transferrin saturation (TSAT) <20%. The primary endpoint was the poor functional outcome at 90days defined as modified Rankin Scale (mRS) 3-6. We used binary logistic regression models including confounding factors to test the association between ID and the primary outcome. The analysis included 442 patients (mean age 73±13, 47.5% female, median NIHSS 7 [IQR 3-15], 61.3% treated with intravenous thrombolysis and/or endovascular treatment). ID prevalence was 65.6%. In all binary logistic regression models, ID predicted poor functional outcome at 3months irrespective from demographics, stroke severity and characteristics, anemia, risk factors, signs/symptoms of heart failure, glucose at admission, and inflammatory biomarkers (aOR 2.328, 95% CI 1.272-4.263, p=0.006). ID was strongly associated with poor functional outcome at 90days in acute ischemic stroke patients. Further research is required to explore whether iron supplementation could be a potential therapeutic strategy to improve patient outcomes.

Abstract TP118: Early Outpatient Follow-up After Acute Ischemic Stroke Reduces 30-day and 90-day Inpatient Readmissions

Introduction: Despite advancements in the management of acute ischemic strokes, readmissions continue to impact both healthcare costs and patient outcomes. The objective of our study was to evaluate factors associated with 30- and 90-day readmissions after acute ischemic stroke including the impact of early transitional care outpatient follow-up by a centralized specialty stroke clinic. Methods: We retrospectively identified all acute ischemic stroke patients discharged from the largest healthcare system in the state of Georgia from October 1, 2022 to March 31, 2024; we excluded patients who were discharged to a long-term acute care or hospice facility. Baseline characteristics, inpatient metrics and post-discharge outpatient follow-up were assessed to identify factors associated with 30- and 90-day inpatient readmission. Results: Of 2191 acute ischemic stroke patients discharged during the study period, 177 (8.1%) and 304 (13.9%) had 30- and 90-day all cause readmissions to the healthcare system, respectively. Increasing age, Charlson Comorbidity Index score, and history of diabetes were independently associated with 30- and 90-day readmission; history of heart failure, obesity, and discharge to inpatient rehabilitation or skilled nursing facility (versus home) were also independently associated with 90-day readmission. Completion of a subspecialty stroke clinic follow-up within 30 days of discharge was associated with a lower likelihood of 30-day (OR 0.64, 95% CI 0.41-0.96; p=0.04) and 90-day readmission (OR 0.69, 95% CI 0.49-0.94; p=0.02). Conclusion: While acute ischemic stroke patients who are older, have comorbid conditions and disability are at an increased likelihood of 30- and 90-day readmission after acute ischemic stroke, our study found that early (&lt;30 day) outpatient follow-up in a subspecialty stroke clinic was associated with a significant reduction in 30- and 90-day readmission. Efforts should be made to ensure early outpatient specialty stroke clinic follow-up for acute ischemic stroke patients after discharge.

Abstract 25: Discovery of Serum Biomarkers to Inform Early Rehabilitation after Acute Ischemic Stroke

Background: Rehabilitation therapy is an important component of acute ischemic stroke (AIS) recovery. A major hinderance is the inability to predict which patients benefit from mobilization during the first 24 hours (ERehab). We hypothesize serum biomarker analyses during the hyperacute phase can bridge the gap. Methods: This is a single center study of 20 AIS patients&amp;14 age/sex matched controls enrolled from 3/2022-6/2023. Serum samples were collected at 4 time points – angiography suite before cerebral reperfusion or Neuro ICU at hospital admission, 12, 24&amp;72 hours. Biomarker candidates were identified using a DisGeNET search for AIS associated proteins; 70% achieved an Evidence Index cutoff score of 1, indicating all publications support human gene-disease or variant-disease associations. Time course of serum proteome changes was evaluated using aptamer-based SomaScan assay, measuring 1500 proteins. NIH Database for Annotation, Visualization&amp;Integrated Discovery (DAVID) Gene Functional Classification Tool compared shared genes and biomarkers for stroke (vs healthy controls)&amp;unfavorable (vs favorable) outcome, characterized by modified Rankin Scale (mRS) score of 3-6 (vs 0-2), at hospital discharge&amp;90 days (90d). Results: The mean age of AIS patients was 59 years, 65% were male. Median NIHSS score was 11, Charlson Comorbidity Index score was 5.5 and the median last known well to hospital admission was 6.6 hrs. The average time to first mobilization was 39 hrs, 25% received ERehab. The mean rehab duration during AIS hospitalization was 438 min; median length of stay was 8.4 days, 40% received post-acute rehabilitation. Median AIS volume was 36mL, 65% of patients had ICA or M1/MCA involvement. Approximately 65% received IV thrombolysis, 80% underwent cerebral reperfusion therapy, 94% achieved modified thrombolysis in Cerebral Infarction score ≥ 2b. The median mRS was 4 at hospital discharge, 3 at 90d. Mortality rate was 10%. DAVID analyses resulted in 22 biomarkers at hospital discharge&amp;35 biomarkers at 90d associated with favorable outcome. Gene expression differences were present at each time point (Figure). Conclusions: We identified multiple serum biomarkers and gene clusters associated with favorable outcomes at hospital discharge and 90d in AIS patients, indicating a need for several biologic targets to predict ERehab response during the hyperacute phase. These findings provide an early framework for tailored stroke recovery interventions.

Abstract TP333: Racial disparities in the management of newly diagnosed diabetes mellitus in Acute Ischemic Stroke

Introduction: Diabetes Mellitus (DM) is a significant risk factor for acute ischemic stroke (AIS) and the incidence of newly diagnosed DM in AIS is higher in certain ethnicities. We aim to examine prescribing patterns of anti-hyperglycemic medications (anti-DM) in hospitalized AIS patients with newly diagnosed with DM. We also examine ethnic disparities in prescribing patterns amongst Hispanic and Non-Hispanic patients. Methods: We retrospectively examined prospectively collected data from an IRB-approved stroke registry at two academic Comprehensive Stroke Centers (CSCs). We included patients with a new diagnosis of AIS with no documented history of DM between 1/1/2013 and 6/30/2024. We examined baseline demographics, comorbidities, ethnicity, insurance status, acute stroke treatment, NIHSS, A1c, blood glucose and their association with anti-DM prescribing patterns. We also evaluated prescribing differences in Hispanic versus Non-Hispanic groups. Data was analyzed using correlation matrix, Pearson’s and Spearman’s correlation coefficients, and Chi-squared and t test, as appropriate. Results: A total of 2870 AIS patients were identified in the study period. Of these, 20.1% (n=578) were Hispanic, 42.5% (n=1219) were female, and 47.8% (n=1373) had Medicare as their payment source. New diagnosis of DM occurred in 6.0% (n=52/863), and 52.0% (n=27) were prescribed anti-DM at discharge. Overall, only a history of previous stroke was independently associated with prescribing anti-DM on discharge (p=0.03). Of patients with new DM, Hgb A1c (p=0.01) and blood glucose (p=0.006) were significantly associated with prescribing anti-DM on discharge. Patients with Medicaid (p=0.04) and no previous medical history (p=0.02) were less likely to receive anti-DM. Mean Hgb A1c was higher in patients that were prescribed anti-DM vs not prescribed anti-DM (8.82 vs. 7.13; p=0.007, 95% CI: -2.87 to -0.52). There was no difference in prescribing anti-DM in Hispanic vs. Non-Hispanic groups. Conclusions: In this study at two academic CSCs, there was no significant difference in prescribing anti-DM medications in Hispanic vs. Non-Hispanic groups, but insurance status may be associated with prescribing patterns. The provision of systematic care helped reduce healthcare disparity in AIS patients with newly diagnosed DM.

Abstract WP7: To study the impact of presenting blood pressure on outcomes in acute ischemic stroke patients. Can permissive hypertension be re-defined with a range?

Abstract WP7: To study the impact of presenting blood pressure on outcomes in acute ischemic stroke patients. Can permissive hypertension be re-defined with a range?

Abstract WMP96: Poor Comprehensive Cerebral Collateral Cascade is Associated with More and Faster Ischemic Core Growth During Inter-Hospital Transfer in Acute Ischemic Stroke Patients with a Large Vessel Occlusion

Abstract WMP96: Poor Comprehensive Cerebral Collateral Cascade is Associated with More and Faster Ischemic Core Growth During Inter-Hospital Transfer in Acute Ischemic Stroke Patients with a Large Vessel Occlusion

Abstract TP1: The Association Between Time and Reperfusion in Acute Ischemic Stroke Patients With Large Vessel Occlusion Treated With Tenecteplase in an Extended Time Window: A Post-hoc Analysis of the Chablis-T Trials

Abstract TP1: The Association Between Time and Reperfusion in Acute Ischemic Stroke Patients With Large Vessel Occlusion Treated With Tenecteplase in an Extended Time Window: A Post-hoc Analysis of the Chablis-T Trials

Abstract WP277: The risk and predictors of stroke recurrence in acute ischemic stroke patients with symptomatic vertebral artery steno-occlusion

Abstract WP277: The risk and predictors of stroke recurrence in acute ischemic stroke patients with symptomatic vertebral artery steno-occlusion

Abstract TP144: Telemedicine Appointments early after Acute Ischemic Stroke may Reduce 30-day Emergency Department Visits

Introduction: Limiting the rate of unplanned emergency department (ED) revisits for patients with acute ischemic stroke is an important aspect of secondary stroke prevention. This is influenced by patients’ demographics, comorbidities, stroke severity, disposition destination, and may be impacted by early outpatient follow-up where stroke risk factors and etiology continue to be evaluated. Methods: We retrospectively identified all acute ischemic stroke patients discharged from an 11-hospital network, the largest healthcare system in the state of Georgia, from October 1, 2022 to March 31, 2024; we excluded patients who were discharged to a long-term acute care or hospice facility. Baseline characteristics, inpatient metrics and post-discharge outpatient follow-up were assessed to identify factors associated with ED visits within 30- and 90-days after discharge. Results: Of 2,191 patients, 143 (6.5%) had ED visits within 30 days and 296 (13.5%) within 90 days. The median age was 68 [IQR 57, 77]. History of heart failure (HF), atrial fibrillation (AF), chronic kidney disease and end stage renal disease each increased the likelihood of an ED re-visit within 30 and 90 days whereas diabetes mellitus increased the likelihood of an ED re-visit at 90 days only. In multiple logistic regression analyses, factors independently associated with 30-day ED visit was a history of HF (OR 1.57, 95% CI 1.07-2.28; p=0.02) and AF (OR 1.49, 95% CI 1.00-2.19; p=0.04); at 90 days, only an increased Charlson Comorbidity Index score was associated with ED visit (OR 1.09, 95% CI 1.02-1.16; p=0.01). There were 501 (23%) patients who completed an outpatient neurology clinic follow-up within 30 days of discharge, including 81 patients (4%) who completed a telemedicine outpatient visit; patients completing a telemedicine visit were less likely to have a 30-day ED visit than those who had an in-person visit (OR= 0.13, 95% CI 0.01-0.62; p=0.05). Conclusion: ED revisits after hospitalization for acute ischemic stroke are relatively common and associated with patients who have comorbid conditions including HF and AF. Our study suggests that telemedicine-based follow-ups were associated with lower rates of unplanned ED revisits within 30 days. Efforts to increase outpatient neurology clinic access through telemedicine may reduce ED visits after discharge for acute ischemic stroke patients.

Abstract WP67: Acute ischemic stroke patients with high senescence gene expression have worse outcomes.

Abstract WP67: Acute ischemic stroke patients with high senescence gene expression have worse outcomes.

Abstract TP360: Increased kynurenine levels are associated with post-stroke infection after controlling for potential confounders

Introduction: Infections account for one-third of stroke deaths. Kynurenine pathway metabolites can modulate the immune response in other contexts. We previously reported a preliminary univariate analysis that showed only significantly elevated kynurenine concentrations among patients who developed a post-stroke infection (PSI), but no differences in other pathway metabolites. This study further characterizes the association between kynurenine and PSI. Methods: Using whole blood samples from acute ischemic stroke patients in the University of Colorado Emergency Medicine Specimen Bank, high throughput mass spectrometry determined kynurenine concentrations. Multivariable linear regression modeled the association between kynurenine and characteristics that could predispose patients to a PSI or alter kynurenine levels (age, sex, NIHSS score, time from sample collection to last known well, and a history of smoking, foley placement or mechanical ventilation, dysphagia, diabetes mellitus, immunosuppression, and chronic kidney disease). Multivariable logistic regression modeled the association between kynurenine and PSI while controlling for the above covariables. Results: Of 75 patients, 32% developed a PSI. Those without a PSI were similar in mean age (64.7+/-12.1years) and race (72.6% white) compared to those with a PSI (age: 69.5+/-13years; 58.3% white). However, patients varied in terms of sex (without PSI: 37.3% female; with PSI: 62.5% female; p=0.04), immunosuppression (without PSI: 5.9% immunosuppressed; with PSI: 20.8% immunosuppressed; p=0.05), and median NIHSS (without PSI: 3.3, IQR 3-7; with PSI: 6.5, IQR 6-7; p=0.03). Only age (point estimate 0.02, p=0.04) and history of chronic kidney disease (point estimate 7.57, p&lt;0.01) were significantly associated with elevated kynurenine concentrations in all stroke patients while controlling for covariables. The odds ratio of developing a PSI for every 1uM increase in kynurenine concentration was 3.46 (95% CI: 1.26 – 9.52). A history of immunosuppression was also associated with an increased odds of PSI (OR 13.21; 95% CI: 2.17-80.49). Conclusion: Elevated kynurenine concentrations are significantly associated with increased risk of PSI, even after controlling for known potential confounders. As expected, immunosuppression was also associated with increased odds of developing a PSI. Furthermore, age and chronic kidney disease in patients with acute ischemic stroke were associated with elevated kynurenine levels.

Abstract TP383: Neutrophil Extracellular Traps (NETs)-related LncRNAs Regulate Thrombus Formation in Acute Ischemic Stroke Patients with Underlying Medical Conditions

Introduction: Acute cerebral blood flow occlusion by thrombus is a major cause of ischemic stroke. The composition of the resulting thrombus varies depending on the underlying medical condition. Notably, neutrophils, the most abundant white blood cells, play a crucial role in acute ischemic stroke and can form neutrophil extracellular traps (NETs). NETs are web-like structures consisting of DNA, granule proteins, and histones. NETs contribute to thrombo-inflammation and stabilize the thrombus, potentially leading to worse outcomes. While long non-coding RNA (lncRNA) do not encode proteins, they are involved in essential biological processes. The link between lncRNAs and cardiovascular disease is increasingly studied, and their role in ischemic stroke has recently come to attention. We, therefore, hypothesize that lncRNAs within NETs play a critical role in the formation and regulation of thrombi. Method: Human thrombi obtained from endovascular thrombectomy were categorized based on their underlying medical conditions, such as dyslipidemia, hypertension, or a combination of two or more conditions. Frozen sections of the thrombi were immunostained with markers including Citrullinated H3 (CitH3), CD45, neutrophil elastase (NE), and DAPI, and then analyzed using holotomography, confocal microscopy, and spatial transcriptomics. In spatial transcriptomics analysis, NETs and other leukocytes were selected as distal and proximal ROIs for detailed gene expression profiling. The gene expression of HDAC class 1 genes (HDAC1, HDAC2, HDAC3, and HDAC8) was further examined by qPCR. Results: Holotomography analysis revealed that cells in the thrombi of patients with underlying conditions exhibited a high mean refractive index. Immunofluorescence imaging also identified a high percentage of NETs in these samples. Spatial transcriptomics analysis confirmed that NETs in patients with hypertension showed upregulated expression of lncRNAs. Additionally, qPCR results demonstrated increased expression of HDAC class 1 genes, which are associated with NET formation, in patients with underlying conditions. Conclusion: LncRNAs play a crucial role in the formation and regulation of thrombi. Therefore, NETs-related lncRNAs could serve as valuable therapeutic targets and diagnostic markers for acute ischemic stroke patients with underlying diseases.

Abstract WP14: Objective Scoring to Reduce Excess Thrombolysis Utilization in Acute Ischemic Stroke Patients with NIHSS ≤ 5

Abstract WP14: Objective Scoring to Reduce Excess Thrombolysis Utilization in Acute Ischemic Stroke Patients with NIHSS ≤ 5

Abstract WP291: Prevalence of Medical Complications in Acute Ischemic Stroke Patients with versus without Cancer

Abstract WP291: Prevalence of Medical Complications in Acute Ischemic Stroke Patients with versus without Cancer

Abstract WMP7: Comprehensive safety and efficacy analysis of the full remote ischemic perconditioning among acute ischemic stroke patients in Catalonia(REMOTECAT) study cohort

Abstract WMP7: Comprehensive safety and efficacy analysis of the full remote ischemic perconditioning among acute ischemic stroke patients in Catalonia(REMOTECAT) study cohort

Abstract TMP73: Endovascular therapy for acute ischemic stroke beyond 24 hours after onset: Japan Stroke Data Bank

Background: The therapeutic time window of endovascular therapy (EVT) for acute ischemic stroke (AIS) has been expanded up to 24 hours of onset. Patients with AIS beyond 24 hours may also benefit from EVT, but the actual status of this clinical issue is unknown. Purpose: To evaluate the real-world status of EVT for AIS beyond 24 hours of onset using a nation-wide stroke registry, Japan Stroke Data Bank (JSDB). JSDB is an ongoing hospital-based multicenter prospective registry of hospitalized patients with acute stroke or transient ischemic attack within 7 days of onset. Methods: From the JSDB dataset, patients with AIS who underwent EVT from 1996 through 2021 were analyzed. Patients were divided into 3 groups according to time from onset to hospital arrival (early: &lt;4.5 hour; late: 4.5–24 hour; and very late: &gt;24 hour). Outcomes included the favorable outcome (mRS 0–2 or return to pre-stroke mRS at discharge) and in-hospital mortality. Results: Among the 256,293 stroke patients, 91,907 AIS patients available for analysis were included in the present study. EVT was implemented in 6.9% (6,356/91,907) (median age 78 years; 41.6% women; median NIHSS score 16). The EVT rate by time window groups was 11.8% (4,258/36,044) for the early, 5.3% (1,676/31,328) for the late, and 1.7% (422/24,535) for the very late group. In the very late group with EVT, baseline NIHSS score was lowest (median 17 points in the early group, 14 points in the late group, and 5 points in the very late group), cardioembolism was least common (67.2%, 53.5%, and 22.0%, respectively), and large artery atherosclerosis was most common (17.9%, 30.8%, and 55.7%, respectively). Favorable outcome was more frequently achieved in the very late group (52.9%) than in the early (41.6%) and late (36.5%) groups. Symptomatic intracranial hemorrhage was more frequently seen in the very late group (6.0%) compared to the early (2.9%) and late (3.8%) groups, but in-hospital mortality was comparable among the time window groups (8.1% in the early group, 7.1% in the late group, and 6.6% in the very late group). Conclusions: Outcomes after EVT for patients with AIS beyond 24 hours were not necessarily worse than for patients with AIS up to 24 hours, but the patient profile in the very late group with EVT differed significantly from that in the early and late groups; developing optimal patient selection strategies for very late AIS may be required.