bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract WP145: Posterior Circulation ASPECTS As A Predictor Of Clinical Outcomes In Basilar Artery Occlusion Requiring Mechanical Thrombectomy.
Authors: mierzwa adam , Salahuddin Hisham , Jumaa Mouhammad , Zaidi Syed , Kung Vieh M , Burgess Richard E , Shawver Julie , Afreen Ehad
Published: February 2022

Introduction:
Acute basilar artery (BA) occlusion represents a catastrophic form of acute ischemic stroke. Mechanical thrombectomy (MT) for this disease is frequently performed, despite the lack of level I evidence. In this study, we aim to identify predictors of good outcome in patients with basilar artery occlusions who underwent MT within 24 hours from last seen normal.

Method:
We conducted a retrospective review study of patients who underwent MT for acute basilar artery occlusions, between October 2012 and October 2018 at our center. The primary endpoint was good functional outcome (modified Rankin Score < 3) at three months. Baseline demographics, clinical, procedural, and radiographic parameters were recorded. We performed a multivariate analysis to determine the predictors of good clinical outcome.

Results:
Our study included 62 patients with basilar artery occlusions treated within 24 hours from last seen normal: 58% of patients achieved good outcome at 90 days. Age, baseline NIHSS, baseline risk factors and rate of IV tPA administration were comparable between the two groups. Patients with good functional outcome at 90 days were less likely to have a history of stroke (13.9% vs 50%,
p
= 0.005), more likely to have a higher PC-ASPECTS (10 vs 8,
p
= 0.0003), and higher successful recanalization rate (91.7% vs 63.6%,
p=
0.01). There was a numerically higher number of patients who achieved good outcome within the early time window (less than 6 hours from last seen normal) compared to the 6-24hr time window (50% vs 31.8%, p=0.23). On multivariate logistic regression analysis, the only independent predictor of good functional outcomes was PC-ASPECTS (OR 2.65, 95 % CI 1.47- 4.75,
p=
0.00114).

Conclusion:
In our cohort of patients with BA occlusion who underwent MT, PC- ASPECTs was an independent predictor of good outcome. Prospective studies are warranted to validate our findings.
Abstract WP165: Clinical And Radiological Characteristics Of Exponential And Non-exponential Infarct Growth Patterns In Anterior Circulation Large Vessel Occlusion Stroke
Authors: Quispe-Orozco Darko , Farooqui Mudassir , Dajles Andres , Zevallos Cynthia , Mendez-Ruiz Alan , Kobsa Jessica , Prasad Ayush , Galecio-Castillo Milagros , Vivanco-Suarez Juan , Bartolome David , Begunova Yelyzaveta , Petersen Nils , Ortega-Gutierrez Santiago
Published: February 2022

Introduction:
Infarct evolution is a highly dynamic process that varies among individuals. This study aimed to identify clinical and radiological features associated with an exponential infarct growth rate (IGR) pattern in stroke patients with large vessel occlusion (LVO).

Methods:
This is a retrospective cohort study of anterior LVO stroke patients who underwent mechanical thrombectomy (MT) and achieved complete recanalization (mTICI 2c-3). Infarct volumes were calculated at two time points, pre-MT: CT perfusion (CTP) using Rapid software to estimate the CBF<30% volume; and post-MT: using DWI-MRI. Early IGR was defined as CBF<30% (ml) / Time from stroke onset to CTP (hours); and late IGR as [DWI-MRI - CBF<30%] (ml) / Time from CTP to reperfusion (hours). Exponential IGR pattern was established when late IGR was at least three times its respective early IGR. Patients who did not meet this criterion were considered to have a non-exponential IGR. Hypoperfusion intensity ratio 0.4 identified patients with poor collateral status. Good functional outcome was defined as 90-day modified Rankin scale (mRS) 0-2.

Results:
Of the 159 patients (median age 71 [6-82], 45% male, median NIHSS 14 [9-18]) included in the analysis, 91 (57%) patients had an exponential IGR pattern. These patients had higher CT ASPECTS (9[7-10] vs 8[7-9], p=0.038), higher glucose levels (126[114-150] vs 117[106-135], p=0.022), lower Tmax<6.0s (88[55-129] vs 113[81-173, p=0.014]), and higher rate of poor collaterals (31% vs 68%, p<0.001) when compared to patients with a non-exponential IGR pattern. Patients with exponential IGR pattern had lower rates of mTICI 3 (82% vs 96%, p=0.008) but no significant differences in mRS 0-2 at 90 days.

Conclusions:
Parameters associated with exponential infarct growth might help to stratify the most time sensitive vulnerable LVO population in which newer therapeutic and triage strategies should be prioritized.

Fig.
Infarct Growth Rate Plots and Collateral Status
. A
shows IGR with an exponential pattern
. B
shows IGR with a non-exponential pattern.
Abstract WP172: Racial Disparities In Perioperative Stroke And Mortality Following Stroke Among Pediatric Cardiac Transplant Recipients
Authors: Lehman Laura L , Salia Soziema , Gupta Suruchi , Barrera Francisco , Liou Lathan , Mostofsky Elizabeth , Murray Mittleman Murray A
Published: February 2022

Introduction:
In the general population, Black children have a higher incidence of stroke and all-cause mortality after stroke. Following cardiac transplantation, mortality is similar across Black and white children within the first 6 months, but Black children have higher mortality beyond 6 months. However, whether there are racial disparities in incidence and all-cause mortality following perioperative stroke among pediatric cardiac transplant recipients is unknown.

Methods:
Using the Scientific Registry of Transplant Recipients, we examined all children in the United States with their first heart transplant from January 1994-September 2019. We used multivariable logistic regression to assess the association between race and perioperative stroke. We used Kaplan Meier survival curves and multivariable piecewise Cox proportional hazard regression to examine the association between race and mortality among children who survived a perioperative stroke.

Results:
Among 8,224 children who had a first cardiac transplant, 255 (3%) had a perioperative stroke. Black children had a 32% lower odds of perioperative stroke compared to white children (OR=0.68, 95%CI 0.46-0.996). In unadjusted and multivariable-adjusted analyses, survival was similar for Black and white children in the first 6 months following perioperative stroke (Figure 1a, adjusted HR = 1.13, 95%CI 0.57-1.83), however Black children had a lower survival probability compared to white children beyond 6 months (Figure 1b, adjusted HR = 3.21, 95%CI 1.19-8.69, log-rank p=0.017).

Conclusion:
Among pediatric cardiac transplant recipients, Black children have a lower incidence of perioperative stroke than white children. Following perioperative stroke during cardiac transplantation, mortality is similar by race, but beyond 6 months, Black children have a higher mortality rate than white children. Intervening on potential differences in care is essential to addressing these disparities.
Abstract WP18: Nanoparticulate Matter Exposure Induces Mature Oligodendrocyte Cell Death And Promotes Oligodendrocyte Precursor Cell Proliferation
Authors: Lamorie-Foote Krista , Shkirkova Kristina , Liu Qinghai , Ge Brandon , Sioutas Constantinos , Morgan Todd E , Finch Caleb E , Mack William
Published: February 2022

Introduction:
Particulate matter exposure (PM), a component of air pollution, promotes neuroinflammation and oxidative stress, which can result in white matter injury. In response to injury, oligodendrocyte precursor cells (OPCs) proliferate and can differentiate into mature oligodendrocytes (mOL). This study aims to characterize the differential effect of nanoparticulate matter (nPM) exposure on OPCs and mOLs in a murine model.

Hypothesis:
We hypothesize that nPM exposure will induce OPC proliferation and result in mOL cell death.

Methods:
nPM (diameter ≤200nm) was collected near an urban area in Los Angeles heavily impacted by traffic-related emissions and re-aerosolized for exposure. Mice (C57BL6/J) aged 10 weeks were exposed to filtered air (FA) or nPM for 5 hours/ day, 3 days/ week, for 10 weeks (150 hours) (n=12/group). Total oligodendrocytes in the corpus callosum were assessed with Olig2 immunofluorescence. OPCs in the corpus callosum were assessed using immunofluorescent double-stains of Olig2 with platelet derived growth factor receptor alpha (PDGFRα). mOLs in the corpus callosum were assessed using immunofluorescent double-stains of Olig2 with CNPase. Two-tailed unpaired Student’s t-tests were used to analyze differences between nPM and FA cohorts. Data shown as mean ± standard deviation, units=cells/mm
2
.

Results:
Total oligodendrocyte cell counts in the corpus callosum were decreased in the nPM (679±88) group compared to FA (811±148, p=0.01). OPC cell counts in the corpus callosum were increased in the nPM cohort (87±12) compared to FA (72±21, p<0.05). mOL cell counts in the corpus callosum were decreased in the nPM group (420±71) compared to FA (602±123, p<0.001).

Conclusions:
nPM exposure induces mOL cell death and promotes OPC proliferation in the corpus callosum. Overall, oligodendrocytes are decreased in the corpus callosum following nPM exposure. These results suggest that an OPC maturation block may occur following nPM exposure.
Abstract WP184: The Risk Of Stroke Recurrence According To Neuroimaging Parameters In Patients With Acute Ischemic Stroke And Atrial Fibrillation
Authors: Kim Do Yeon , Han Seok-Gil , Jeong Han-gil , Lee Keon-joo , Kim Beom J , Han Moon-Ku , Choi Kang-Ho , Kim Joon-tae , Shin Dong-Ick , Cha Jae-kwan , Kim Dae Hyun , Kim Dong E , Ryu Wi-Sun , Park Jong-moo , Kang Kyusik , Kim Jae , Lee Soo Joo , Oh Mi Sun , Yu Kyung-Ho , Lee Byung-chul , PARK Hong-kyun , Hong Keun-sik , Cho Yong-Jin , Choi Jay Chol , Sohn Sung-il , Hong Jeong-ho , Park Tai Hwan , Lee Kyung Bok , Kwon Jee-Hyun , Kim Wook-joo , Lee Jun , Lee Ji Sung , LEE JUNEYOUNG , BAE Hee-joon
Published: February 2022

Purpose:
The usefulness of the existing risk stratification tools for atrial fibrillation (AF) is limited in predicting stroke recurrence in patients with acute ischemic stroke (AIS). Neuroimaging parameters obtained from diagnostic work-up of AIS could offer more elaborate prediction.

Methods:
A multicenter prospective cohort of AIS patients with AF recruited from 14 university hospitals or regional stroke centers were followed up for recurrent ischemic stroke (RIS) and a composite of all stroke and TIA. Neuroimaging features were derived from acute and chronic infarction patterns, and SVD markers such as lacunes, CMBs, and WMH. Cumulative incidences according to each neuroimaging parameter were estimated and compared using the Kaplan-Meier method with log-rank test and multivariable cause-specific hazard models with death as a competing risk.

Results:
A total of 2,270 patients were followed up for 431 days (IQR, 365-735), during which 111 RISs and 130 composite outcomes occurred. In unadjusted analysis, lesion multiplicity among acute infarction patterns, the presence of chronic non-lacunar infarction, and the presence of lacunes among SVD markers increased the risk of RIS significantly (Table). Other neuroimaging features such as territory multiplicity and location, confluency, topography, and size of acute lesions, lesion multiplicity, territory multiplicity, confluency, topography, and size of chronic infarction, number of lacunes, presence of CMBs, and WMH did not affect the incidence of RIS. The adjusted hazard ratios of lesion multiplicity of acute infarction, chronic infarction and lacunes were 1.45 (95% CI, 0.99-2.11), 1.57 (1.06-2.34) and 1.97 (1.30-2.98) for RIS, respectively. Similar findings were obtained for the composite outcome.

Conclusions:
Several neuroimaging markers were associated with recurrent ischemic stroke in AIS with AF. This could pave the way to a new stratification scheme for AF including neuroimaging parameters.
Abstract WP186: Long-term Incidence Of Gastrointestinal Bleeding After Ischemic Stroke
Authors: Kim Jun , Lee Keon-joo , Kim Beom , Kang Jihoon , Han Moon-Ku , Kim Seong-Eun , Park Jong-moo , Kang Kyusik , Lee Soo Joo , Kim Jae , Cha Jae-kwan , Kim Dae-Hyun , Park Tai Hwan , Lee Kyung Bok , PARK Hong-kyun , Cho Yong-jin , Hong Keun-sik , Choi Kang-Ho , Kim Joon-tae , Kim Dong-Eog , Ryu Wi-Sun , Choi Jay Chol , Oh Mi-Sun , Yu Kyung-Ho , Lee Byung-chul , Park Kwang-yeol , Lee Ji Sung , LEE JUNEYOUNG , BAE Hee-joon
Published: February 2022

Background:
Incidence of gastrointestinal (GI) bleeding after acute ischemic stroke (AIS) was reported as 1.5% during hospitalization, one-thirds of which required blood transfusion. However, it is not known about the long-term incidence and the incidence rates by period after AIS.

Methods:
AIS patients who were admitted to the 14 participating hospitals between 2011 and 2013 were identified using a nationwide multicenter prospective stroke registry database. GI bleeding was captured with related diagnosis codes by International Classification of Diseases-10th Revision through the linkage between the registry database and the claims data. Bleeding requiring at least 2 packs of blood transfusion was defined as major GI bleeding. Incidence rates were calculated for each period as follow; 0-30 days, 31-90 days, 91-180 days, 181-365 days, 1-2 years, 2-3years, after 3 years.

Results:
Of 10,818 AIS patients, 59.0% were male and mean age was 67.5 ± 12.9 years. The median follow-up duration was 3.1 (interquartile range 2.3 to 4.0) years. During 31,208 person-years, 947 patients (8.8%) had 1,224 episodes of major GI bleeding. Annual incidence rate was 3.92 per 100 person-years. The incidence rates by periods were the highest at 19.21 per 100 person-years in the first month of AIS, gradually decreased to 9.02 in one to three months, 6.18 in three to six months, and 3.48 in six to twelve months. After three years, it remained at about 2.62 events per 100 person-years. During the observation period, only one major GI bleeding occurred without recurrence in about 80% of patients, about 13% recurred twice, and about 6% of patients had three or more recurrences. In the multivariable recurrent event analysis, anemia at admission, lower eGFR below 60, and mRS at 3 months ≥4 were independently associated with higher risk of major GI bleeding during the most of the observation period above 3 years.

Conclusions:
Major GI bleeding, requiring transfusion, seems to occur frequently after AIS, and the risk was gradually decreased after stroke. The efforts are needed to prevent it, especially in stroke patients with anemia and decreased renal function.
Abstract WP191: Genetic Analyses Support A Causal Role Of Lung Cancer In Ischemic Stroke
Authors: Vanent Kevin N , Acosta Julian N , Both Cameron , Leasure Audrey C , Torres Lopez Victor , Szejko Natalia , Rivier Cyprien , de Havenon Adam H , Sharma Richa , Levitt Michael R , Sheth Kevin N , Falcone Guido J
Published: February 2022

Introduction:
Lung cancer has been linked to increased risk of thromboembolic events, including stroke. However, a causal relationship between lung cancer and ischemic stroke (IS) has yet to be established.

Methods:
We conducted a two-stage study using observational and genetic data from the UK Biobank, a large cohort study that enrolled over 500,000 Britons aged 40-69. We included participants of European descent. In Stage I, we used logistic regression to test the association between self-reported / ICD-defined lung cancer and risk of IS. In Stage II, we constructed a polygenic risk score (PRS) using 31 independent genetic variants known to associate with lung cancer, fitted logistic regression to assess the relationship between this PRS and risk of IS, and implemented the inverse variance weighted method of Mendelian randomization (MR). We tested for horizontal pleiotropy using the MR-Egger and MR Pleiotropy Residual Sum and Outlier (MR-PRESSO) approaches.

Results:
Out of 409,629 participants of European descent enrolled in the UK Biobank, there were 5,060 IS cases (mean age, 61.6 [standard deviation 6.5]; female sex, 1813 [35.8%]). The prevalence of lung cancer was 1.9% (n=94) and 0.5% (n=1,961) among persons with and without IS, respectively (unadjusted p<0.001). In multivariable analyses, self-reported / ICD-defined lung cancer was associated with a 54% increase in risk of IS (adjusted OR, 1.54; 95% CI, 1.30-1.81; p<0.001). Genetic analyses supported a causal link between lung cancer and IS. In PRS analysis, each additional standard deviation of the lung cancer-related PRS was associated with a 3% increase in risk of IS (adjusted OR, 1.03; 95% CI, 1.01-1.06; p=0.018). In MR analysis, genetically determined lung cancer was associated with a 5% increase in risk of IS (OR, 1.05; 95% CI, 1.01-1.09; p=0.022). There was no significant horizontal pleiotropy (MR-Egger intercept p=0.663; MR-PRESSO global test p=0.993).

Conclusions:
Genetically determined lung cancer is associated with increased risk of ischemic stroke. These findings provide evidence for a causal link between lung cancer and ischemic stroke. Further studies are needed to identify the biological pathways that mediate this link.
Abstract WP2: Videooculography-assisted Head Impulse Test And Caloric Testing Improve Clinical Algorithms For Detecting Stroke In Acute Vertigo Patients
Authors: Siepmann Timo , Gruener Cosima , Simon Erik , Sedghi Annahita , Kitzler Hagen H , Pallesen Lars P , Reichmann Heinz , Puetz Volker , Barlinn Kristian
Published: February 2022

Introduction:
Stroke accounts for 4% of patients with acute vertigo, which is missed in up to one third of cases.

Hypothesis:
We hypothesized that detection of stroke underlying acute vertigo using HINTS plus (head-impulse test, nystagmus type, test of skew, hearing loss) can be improved by videooculography for automated analysis of head-impulse test (V-HIT).

Materials and Methods:
We evaluated patients with acute vestibular syndrome (AVS) presenting to the emergency room using HINTS plus and V-HIT-assisted HINTS plus in a randomized sequence. In addition, patients underwent cranial MRI and caloric testing. Image-confirmed posterior circulation stroke or vertebrobasilar TIA were defined as reference standard to calculate accuracy of applied vertigo assessment protocols. After study completion, we repeated statistical analysis for a third protocol that was composed post hoc by replacing the results of head-impulse test with those derived from caloric testing in the HINTS plus protocol.

Results:
We included 30 AVS patients (ages 55.4 ± 17.2 years, 14 females). Of these, 11 (36.7%) had MRI-confirmed posterior circulation ischemic stroke (n=4) or vertebrobasilar TIA (n=7). Conducting V-HIT-assisted HINTS plus as part of the emergency work up was feasible and displayed a tendency toward higher accuracy than conventional HINTS plus (sensitivity: 81.8%, 95%CI 48.2-97.7%; specificity 31.6%, 95%CI 12.6-56.6% vs. sensitivity 72.7%, 95%CI 39.0-94.0%; specificity 36.8%, 95%CI 16.3-61.6%). (Figure) The new caloric-supported algorithm displayed high accuracy (sensitivity 100%, 95%CI 66.4%-100%; specificity 66.7%, 95%CI 41%-86.7%).

Conclusions:
Our study provides pilot data on the capacity of videooculography to improve accuracy of acute vertigo assessment using HINTS plus and indicates potential value of acute caloric testing as integrative part of standardized AVS emergency work up.
Abstract WP204: Patients With Traditional Cerebrovascular Risk Factors Are At A Higher Risk Of Stroke After Cervical Artery Dissection
Authors: Garg Aayushi , Leira Enrique C. C , Shaban Amir
Published: February 2022

Background:
Ischemic stroke is a common complication of cervical artery dissection (CeAD), however, the factors predisposing to stroke are unclear. We aimed to evaluate the timing and risk factors of ischemic events in patients with CeAD.

Methods:
We identified hospitalizations with carotid artery dissection (CAD) and vertebral artery dissection (VAD) from the Nationwide Readmissions Database 2016-2018. Multivariable logistic regression and Cox regression analyses were used to evaluate the risk factors associated with ischemic events during the index hospitalization and after hospital discharge, respectively.

Results:
There were 38824 hospitalizations due to CeAD (mean±SD age: 53.7±18.3 years, female: 43.2%); 19769 (50.9%) with acute ischemic stroke (AIS) or transient ischemic attack (TIA) and 19055 (49.1%) without any ischemic events during the initial hospitalization. Advanced age, female sex, both CAD and VAD (in reference to VAD alone), and history of Marfan’s syndrome were associated with lower odds of ischemic events. Whereas history of hypertension, hyperlipidemia, diabetes, tobacco use, obesity, and previous stroke/TIA were associated with higher likelihood of ischemic events at initial presentation. Among 32862 index cases with survival to discharge and known discharge disposition, readmission due to acute ischemic events within 1 year of discharge occurred in 924 (2.8%) patients, with mean±SD time to readmission: 56.6±70.8 days. The risk of readmission due to ischemic events did not differ by the location of CeAD. However, AIS/TIA during the index hospitalization [hazards ratio (HR): 3.1, 95% confidence interval (CI): 2.5-4.0), history of hyperlipidemia (HR: 1.3, 95% CI: 1.1-1.6), diabetes (HR: 1.5, 95% CI: 1.2-1.8), tobacco use (HR: 1.3, 95% CI: 1.1-1.6), and head/neck vessel atherosclerosis (HR: 1.3, 95% CI: 1.1-1.6) were independently associated with a higher risk of delayed ischemic events.

Conclusion:
Nearly half of the hospitalized patients with CeAD have ischemic events at initial presentation. Delayed ischemic events are possible, however, occur in a relatively small proportion of patients. Comorbid cerebrovascular risk factors are associated with both concurrent and delayed ischemic events in patients with CeAD.
Abstract WP205: Trans-ethnic Genome-wide Association Studies Meta-analysis Of Large Brain Arterial Diameters Identifies Two Novel Genetic Loci
Authors: Liu Minghua , Khasiyev Farid , Wasserman Bruce A , Qiao Ye , Thomas Emy Anu , Elkind Mitchell S , Sacco Ralph L , Rundek Tatjana , Tosto Giuseppe , Sariya Sanjeev , Hilal Saima , Seshadri Sudha , Romero Jose R , Yang Qiong , Fornage Myriam , Gutierrez Jose
Published: February 2022

Introduction:
Larger brain arterial diameters, which may be a consequence of connective tissue disorders or hypertension, are associated with mortality, cognitive decline and risk of dementia. Whether there may be genetic determinants of large brain arterial diameters is unknown, but identifying such traits may shed light into possible mechanistic links between large brain arterial diameters and the observed outcomes.

Methods:
We studied 3654 participants from four ethnically diverse population-based cohorts: The Atherosclerosis Risk in Communities study (n=1565: 74.3% white, 25.7% black), The Northern Manhattan Study (n=1092: 13.8% white, 16.6% black, 69.6% Hispanic), Epidemiology of Dementia in Singapore (n=647: 31.7% Chinese, 35.7% Malay, 32.6% Indian), and Memory Clinic Cohort in Singapore (n=350: 84.9% Chinese, 7.8% Malay, 7.3% Indian). We measured brain arterial diameters for 13 segments and normalized the averaged diameter per participant to obtain global brain arterial diameter as dependent variable. Genome-wide association studies (GWAS) was performed in each study using linear regression, adjusted for sex, age, head size, number of missing arteries and population substructure. Meta-analysis of association statistics was performed using the METAL to generate combined trait-specific effect estimates. We also performed trans-ethnic meta-regression by MR-MEGA to account for the heterogeneity in allelic effect that is correlated with ancestry.

Results:
Genome-wide significant (P<5x10
-8
) associations were observed for global brain arterial diameter with three SNPs: rs7921574(P=1.2x10
-8
) mapping to an intron of CNNM2; rs2075858(P=2.47x10
-8
) and rs2075857 (P=2.37x10
-8
) mapping to introns of MUC5B. MR-MEGA analysis showed suggestive evidence of association (P=5.05x10
-8
) for rs7921574. These loci comprise genes involved in response to magnesium transport, neuronal transmission, hypertension, mucociliary clearance and host defense.

Conclusion:
Our study reveals two novel risk loci for large brain arterial diameters. We have begun to replicate these associations and to identify functional causal variants in independent studies. Identifying these loci may help us to elucidate underlying disease mechanisms.
Abstract WP209: Efficacy And Safety Of Early Anticoagulant Therapy Initiation In Patients With Acute Ischemic Stroke Related To Atrial Fibrillation: A Systematic Review And Meta-analysis
Authors: Katsanos Aristeidis , Palaiodimou Lina , Stefanou Maria-Ioanna , Paciaroni Maurizio , Caso Valeria , Seiffge David , De Marchis Gian Marco , Shoamanesh Ashkan , Malhotra Konark , Aguiar de Sousa Diana , Lambadiari Vaia , Kantzanou Maria , VASSILOPOULOU SOPHIA , Toutouzas Konstantinos , Yaghi Shadi , Tsivgoulis Georgios
Published: February 2022

Background:
The optimal timing for the initiation of anticoagulation in patients with acute ischemic stroke (AIS) related to atrial fibrillation (AF) remains uncertain. Observational studies assessing early anticoagulant initiation (≤14 days after index AIS) have provided conflicting results from the early use of non-vitamin K oral anticoagulants (NOACs) or vitamin K antagonists (VKAs).

Methods:
We performed a meta-analysis of prospective observational studies and RCTs to assess the efficacy and safety of early anticoagulation in AF-related AIS. We also compared the efficacy and safety between NOAC and VKA regimens. A random-effects model was used to pool the individual risk ratios (RRs) and corresponding 95% confidence intervals (CIs) between the two groups. Recurrent ischemic stroke was defined as the primary outcome.

Results:
Nine eligible studies (7 observational, 2 RCTs) were identified, including 6,840 patients with AF-related AIS (pooled mean baseline NIHSS score: 5.5; 95%CI: 3.7-7.2) who received early anticoagulation. The overall ischemic stroke recurrence rate was 5% (95%CI: 3.3-7%) and differed (p=0.05) between studies reporting anticoagulation initiation within a week (2.5%, 95%CI: 0.2-7.4%) or two weeks (6.7%, 95%CI:4.6-9.1%) from index event. The corresponding proportions of patients experiencing a fatal outcome, symptomatic or asymptomatic ICH were 4% (95%CI: 1.6-7.5%), 1.2% (95%CI: 0.3-2.6%) and 13.2% (95%CI: 6.4-22.1%), respectively. Of the 2 identified RCTs, 136 and 135 patients were randomized to early anticoagulation with NOAC or VKA, respectively. Both groups had a similar risk for ischemic stroke recurrence (RR=0.78; 95%CI: 0.32, 1.91; p=0.59). No significant differences were uncovered between early NOAC or early VKA treatment initiation for the outcomes of mortality (RR=0.57; 95%CI: 0.11, 2.97; p=0.51), symptomatic ICH (RR=0.38; 95%CI: 0.02, 9.10; p=0.55) or asymptomatic ICH (RR=1.10; 95%CI: 0.73, 1.67; p=0.64).

Conclusions:
Preliminary evidence from RCTs on early anticoagulation after AF-related AIS suggest that NOACs have comparable efficacy to VKAs in preventing ischemic stroke recurrence. Large scale RCTs are warranted to evaluate the potential superiority of NOACs in terms of safety endpoints.
Abstract WP21: Cognitive Improvement In Patients With Dural Arterio-venous Fistula After Endovascular Embolization: Interim Analysis Of The NAIF Study
Authors: Gramegna Laura , Gemma Ortega , Dinia Lavinia , Rosati Santiago , VEGA PEDRO , gonzalez alejandro , Luttich Alex , Aixut Lorenzo Sonia , Quintana Manuel , tomasello alejandro
Published: February 2022

Introduction:
Dural arteriovenous fistulae (dAVF) are rare acquired intracranial vascular malformations with clinical manifestations varying from asymptomatic lesions, non-hemorrhagic neurological disorders, and intracranial hemorrhage which may be fatal. In addition, patients with dAVF often have cognitive impairments. This study assessed whether endovascular embolization improves cognitive performance in patients with dAVF.

Methods:
NAIF was a prospective study including all the patients with a clinical diagnosis of dAVF (excluding those with acute intracranial hemorrhage secondary to venous hypertension) who underwent successful embolization at 5 hospitals in Spain between January 4, 2018 and January 7, 2020. Patients were categorized by risk of hemorrhage (Cognard classification 1-2A and 2B-4) via angiography. A neuropsychological evaluation covering 5 domains of cognitive function (memory, attention and executive functions, language, praxis, gnosis) was completed at baseline and a 3-month follow-up. Paired sample t-tests were used to compare mean Z-scores for cognitive tests pre- and post-treatment, where higher Z-scores signify better cognitive status.

Results:
A preliminary group of 15 patients (mean age 60, [range 23-83 years], 4 [26.7%] female) were included. Six patients presented with low hemorrhagic risk (Cognard1-2A) and 9 with high hemorrhagic risk (Cognard 2B-4). In the post-treatment neuropsychological evaluation, patients exhibited improved performance in executive function in the Semantic and Phonetic Fluency test (-0.57 vs. 0.21; p=0.01) and increased performance in Verbal Memory Learning (-1.45 vs. -0.82; p=0.014) relative to baseline. The remaining cognitive evaluations did not show significant differences, although there was a trend of language improvement in the Boston naming test (0.95 vs. 1.12; p=0.093). Improvements were observed in both high- and low-risk patients, and no patients experienced cognitive worsening after the intervention.

Conclusion:
This study suggests that endovascular embolization imparts cognitive benefits for dAVF patients undergoing endovascular embolization, and may be beneficial even for patients with a low risk of hemorrhage.
Abstract WP218: Midlife Blood Pressure Trajectory And Later Life Risk Of Ischemic Stroke: A Post-hoc Analysis Of ARIC
Authors: de Havenon Adam H , Yaghi Shadi , Anadani Mohammad , Mistry Eva , Petersen Nils H , Prabhakaran Shyam , Lansberg Maarten G , Sheth Kevin N
Published: February 2022

Introduction:
Midlife hypertension is associated with an increased later-life ischemic stroke risk. However, temporal trends of blood pressure have not been fully explored.

Methods:
We performed a post hoc analysis of the ARIC study and included participants with four systolic blood pressures (SBP) at Visits 1-4 (1987-1999). Patients who had an ischemic stroke, died, or were lost to follow-up before 1999 were excluded from the analysis. We used group-based trajectory modeling to define six distinct SBP trajectories during Visits 1-4 (Figure 1). We report unadjusted and adjusted hazard ratios from Cox models fit to the primary outcome of ischemic stroke during follow-up from 1999-2017. We confirmed the proportional hazards assumptions of our models.

Results:
We included 9,689 participants, of which 758 (7.8%) had an ischemic stroke during follow-up. The mean±SD age at Visit 1 was 54±6 years and at Visit 4 was 63±6 years. The adjusted Cox models, Table 1, show the highest risk of ischemic stroke with increasing hypertension or stable severe hypertension. Comparing trajectories with similar baseline hypertension confirmed that increasing hypertension and stable severe hypertension had a higher risk than decreasing trajectories with the same starting point.

Conclusion:
Midlife blood pressure trajectory is associated with later-life ischemic stroke risk. Patients with hypertension who achieved a midlife reduction in systolic blood pressure were less likely to have a later-life stroke than those who did not.
Abstract WP221: Sex Differences In The Symptom Presentation Of Stroke: A Systematic Review And Meta-analysis
Authors: Shajahan Sultana , Sun Lingli , Wang Xia , Harris Katie , Sandset Else C , Woodward Mark , Peters Sanne A , Carcel Cheryl
Published: February 2022

Background:
Early diagnosis through symptom recognition is vital in acute stroke management. However, women who experience stroke are more likely than men to receive a missed or delayed diagnosis.

Aims:
To assess sex differences in the symptom presentation of stroke and whether these differences are associated with a delayed or missed diagnosis.

Methods:
PubMed, EMBASE and the Cochrane Library were systematically searched up to January 2021 for all studies that reported on symptoms in both adult women and men with diagnosed stroke (ischaemic or haemorrhagic) and transient ischaemic attack and were published in English. Sex-stratified proportions for each symptom were extracted and pooled. The relative risk (RR) of a symptom being present in women relative to men with 95% confidence intervals (CI) was also calculated and pooled, as well as the RR of a delayed or missed stroke diagnosis.

Results:
Pooled results from 21 eligible articles showed that the top three symptoms were similar between women and men - limb weakness (72% vs. 66%), hemiparesis (56% vs. 55%), and weakness of the face, arm or leg (55% vs. 55%). However, the top 4th and 5th symptoms found in women were generalised non-specific weakness (49%) and motor deficit (46%), whereas in men these were motor deficit (46%) and ataxia (44%). In addition, crude RR showed that women were more likely to have higher risk than men of presenting with confusion (RR 1.16, CI 1.01-1.32), dysphagia (RR 1.29, CI 1.13-1.48), dysphasia (RR 1.11, CI 1.00-1.24), fatigue (RR 1.42, CI 1.05-1.92), generalised weakness (RR 1.56 CI 1.23-1.98), headache (RR 1.14, CI 1.01-1.30), urinary incontinence (RR 1.25, CI 1.17-1.33), loss of consciousness (RR 1.30, CI 1.12-1.51), and mental status change (RR 1.37, CI 1.18-1.58), and lower risk of presenting with dizziness (RR 0.87, CI 0.80-0.95), dysarthria (RR 0.89, CI 0.82-0.95), imbalance (RR 0.68, CI 0.57-0.81), paraesthesia (RR 0.74, CI 0.58-0.93), and trouble walking (RR 0.83, CI 0.70-0.99). Finally, pooled RR of delayed or missed diagnosis for women compared to men was not statistically significant (RR 1.19, CI 0.94-1.49).

Conclusion:
Though women and men commonly presented with similar symptoms, some sex differences were present which needs consideration in stroke evaluation.
Abstract WP222: Outcome Of ESUS With Possible Embolic Sources.
Authors: Kida Hiroyuki , Sato Takeo , Kitagawa Tomomichi , Nakada Ryoji , Takatsu Hiroki , Komatsu Teppei , Sakuta Kenichi , Sakai Kenichiro , Umehara Tadashi , Mitsumura Hidetaka , MURAKAMI HIDETOMO , Iguchi Yasuyuki
Published: February 2022

Background and Purpose:
Our aim is to investigate the factors of outcome in ESUS with possible embolic source (PES) caused by non-high risk cardiac sources, malignancy, and mild atherosclerosis.

Methods:
Patients were selected from a comprehensive stroke center between April 2013 and April 2021. Inclusion criteria were: 1) consecutive ischemic stroke patients who fulfilled ESUS criteria based on NAVIGATE-ESUS trial, 2) who underwent TEE 3) who admitted our hospital within 7 days from stroke onset 4) pre stroke modified Rankin scale (mRS) score below 1 and 5) available mRS score at 3 months from stroke onset. PES included atrial cardiopathy (large left atrium diameter, slow out flow in left atrium appendage, and frequent premature atrium contraction), left ventricular dysfunction (history of heart failure, abnormal ventricular wall motion, and reduced ejection fraction), cardiac valve disease, right-to-left shunt, malignancy, and atherosclerosis (ipsilateral carotid plaque and aortic complicated lesion). We compared PES, between mRS score 0-1 (favorable outcome group) and mRS score 2-6 (unfavorable outcome group).

Results:
We screened 1,824 consecutive ischemic stroke patients, including 191 in ESUS patients. 159 (83%) patients were ESUS with PES. Of all, 33 patients had unfavorable outcomes (25 [76%] male, median age 64 years old, Figure A). Higher National Institute of Health Stroke Scale score on admission (OR 4.50, 95%CI 1.96-10.30,
p
<0.001) and higher frequency of atherosclerosis (OR 2.67, 95%CI 1.11-6.44,
p
=0.028) were independently associated with unfavorable outcome (Figure B).

Conclusions:
Atherothrombotic emboli may contribute to outcome of ESUS with PES.
Abstract WP228: Normal Left Atrial Diameter Is Associated With Better Performance On A Telephone Cognition Screening Tool Among Ischemic Stroke Survivors
Authors: Gootee Emma , Stein Colin , Walker Alexandra , Daneshvari Nicholas , Burton Kate , Schneider Andrea , Blaha Michael J , Lima Joao A , Gottesman Rebecca F , Johansen Michelle C
Published: February 2022

Background:
Cardiac structure and function are important in determining ischemic stroke (IS) etiology, but whether there is an association with cognition post IS is unknown.

Methods:
IS patients admitted to Johns Hopkins Hospital (2017-2019) underwent transthoracic echocardiography. IS was classified (TOAST) by a masked reviewer. Parasternal short axis left atrial (LA) diameter was evaluated as a continuous variable with a spline at 4cm (normal ≤4cm versus enlarged >4cm); left ventricle ejection fraction (LVEF) was evaluated as a nonlinear continuous variable with two spline knots at 40% and 65%. Cognition was assessed by telephone using the Six Item Screener (SIS), which tests orientation (day, month, year) and recall (grass, paper, shoe) and was dichotomized into low (0-3, worse score) and high (4-6, better score), and conservatively imputing low category scores for non-answerers. Multivariable logistic regression determined the association of SIS category with LA or LVEF, each, adjusted for covariates.

Results:
Participants (N=119) were on average 60 (18-89) years, 60% male, and 59% Black. Mean LA diameter was 3.9cm (
SD
=0.8) and mean LVEF 61.4% (
SD
=10.5). For LA diameter ≤4cm, each 1cm increase was associated with 5.93 greater odds (95% CI=1.49-23.65) of scoring in the high SIS category, while for LA diameter >4cm each 1cm increase was associated with lower odds (OR=0.88, 95% CI=0.39-1.99) of scoring in the high SIS category (Figure 1). Decreased (OR=0.91, 95% CI=0.74-1.11), normal (OR=0.98, 95% CI=0.91-1.06) or hyperdynamic LVEF (OR=1.02, 95% CI=0.90-1.14) showed no relationship with SIS category.

Conclusions:
In this study, a 1cm change in LA diameter was significantly associated with a higher score on a telephone cognition screening test, if patients had a LA diameter within normal range, but without the same association with SIS if the LA diameter was >4cm. We cautiously suggest that LA function may be associated with cognition post-stroke.
Abstract WP230: Interpretable Machine Learning Models For Predicting 30-Day All-Cause Readmission Following Carotid Endarterectomy Among Acute Ischemic Stroke Cases: A NSQIP Study (2014 - 2017)
Authors: Saxena Anshul , Ahmed Md Ashfaq , Zhang Zhenwei , Rubens Muni , Ramamoorthy Venkataraghavan , McGranaghan Peter , Veledar Emir
Published: February 2022

Background:
Acute ischemic stroke (AIS) patients show a good prognosis with Carotid endarterectomy (CEA). However, lowering short-term readmissions after CEA for AIS cases remains a significant challenge. Several machine learning (ML) models predicting readmissions fail to explain the predictors. Hence the utility of such ML models in clinical settings is limited. This study used interpretable machine learning (ML) methods to identify the predictors associated with 30-day readmission.

Methods:
We utilized the National Surgical Quality Improvement Program registry (2014-2017) for this study. Patients aged >18 years and who underwent CEA for AIS were included. ICD-9, ICD-10, and CPT codes were used to identify AIS and CEA cases. Decision Trees and Random Forest classification techniques were utilized to identify predictors of 30-day readmission.

Results:
A total of 22,373 AIS patients underwent CEA during the study period. The mean (SD) age of the patients was 70.7 (9.4) years, and the majority (61%) were males. About 80% were Non-Hispanic White, followed by non-Hispanic Black (4.6%). About 7% of AIS patients who underwent CEA had 30-day readmission. Random Forest classification and Decision Tree were able to provide clinically relevant predictors and cut-off values. For example, one of the top predictors was pre-operative Hematocrit, and its cut-off value of ≤33% with Diabetes showed a higher risk for readmission.

Conclusion:
Our study showed that interpretable ML models could be helpful for clinicians to stratify patients based on their pre-operative risk for a 30-day readmission and could help optimize management strategies for improving patient outcomes. Incorporating these cut-off values in EMR could help clinical decision-making and plan interventions to reduce readmissions by managing risk factors. This would improve the quality of care and save high healthcare costs.
Abstract WP233: Socioeconomic Status And Comorbidity Variance In Ischemic Stroke
Authors: Kiser Ryan M , Schutz Rachael , Kalani Rizwan , de Havenon Adam H , Davis Arielle , Longstreth W T , Tirschwell David L
Published: February 2022

Introduction:
Socioeconomic status (SES) is an upstream determinant of cerebrovascular disease comorbidities and subsequently ischemic stroke. Here we examined the association of SES and modifiable ischemic stroke risk factors.

Methods:
Hospitalized ischemic stroke patient data from 10/1/2015 - 12/31/2018 was obtained via the Healthcare Cost and Utilization Project Nationwide Inpatient Sample (NIS). Demographic characteristics of age, sex, race, US region, SES (defined as median household income range by zip code) and ischemic stroke risk factors of atrial fibrillation/flutter (AF), type II diabetes (DM), hypertension (HTN), hyperlipidemia (HLD), tobacco use, and obesity were identified using published ICD-10 codes. Multivariable logistic regression was used to assess each condition individually and identify which comorbidities were associated with specific socioeconomic quartiles (Q1, Q4) when adjusted for the abovementioned demographics.

Results:
Of the 382,734 adult ischemic stroke patients identified, mean age was 70 ±14.2 years and 50.3% were female. Socioeconomic status quartiles ranged from <$43,749 (Q1) to >$73,000 (Q4); 30.9% of ischemic stroke patients were in SES Q1 (vs 19.1% in SES Q4). Patients in Q1 experienced ischemic stroke at a younger age (67.9 ±14.1) as compared to patients in Q4 (72.4 ±14), p<0.001. In adjusted models with Q4 as reference, Q1 patients had increased odds for DM [OR 1.27, p<0.001, 95% CI 1.24 - 1.29], obesity [OR 1.05, p<0.004, CI 1.02 - 1.08], and tobacco use [OR 1.66, p<0.001, CI 1.51 - 1.83]. Conversely, Q1 patients had decreased odds of AF [OR 0.91, p<0.001, CI 0.89 - 0.93] and HLD [OR 0.81, p<0.001, CI 0.79 - 0.82]. There was no significant association between SES quartile and HTN.

Conclusion:
Lower SES was associated with higher odds of specific ischemic stroke risk factors. While the etiology of the risk factor variance is beyond the scope of current data analysis, the cause is likely multifactorial and influenced by underlying detection bias, income inequity, and level of education/health literacy. Further research and subgroup analysis is warranted as it may impact future preventative measures and treatment protocols.
Abstract WP236: The Gut Microbiome Is Associated With Early Brain Injury After Experimental Subarachnoid Hemorrhage Via Regulation Of Neutrophils
Authors: Kawabata Shuhei , Takagaki Masatoshi , Nakamura Hajime , Nishida Takeo , Izutsu Nobuyuki , Takenaka Tomofumi , Matsui Yuichi , Yamada Shuhei , Terada Eisaku , Nakagawa Ryota , Kishima Haruhiko
Published: February 2022

Background:
It is known that early brain injury (EBI), which occurs early after the onset of subarachnoid hemorrhage (SAH), largely determines the prognosis of SAH; however, an effective treatment for EBI has not been developed. The outcome of various diseases including ischemic stroke is influenced by the composition of the gut microbiome (GM) and we have previously shown that the GM is also associated with the rupture of cerebral aneurysms. Here, we studied whether prior alteration of the GM can prevent EBI after SAH.

Methods:
We altered the GM of 7-week-old male rats by administering antibiotics-containing water for 2 weeks or performing fecal microbiome transplantation after antibiotics treatment. The composition of the GM was profiled using 16S rRNA. SAH was induced by injection of blood in the subarachnoid space of control rats and rats with altered GM. We evaluated EBI indicators such as the neurological score, brain water content, Evans blue extravasation, and neuronal apoptosis. We also studied inflammatory cells using immunohistochemistry, immunocytochemistry, quantitative PCR and flow cytometry.

Results:
There were significant differences in alpha and beta diversity between the control and antibiotics-treated rats. Compared with the control rats, the antibiotics-treated rats had significantly reduced neurological symptoms, brain edema, blood-brain barrier disruption and apoptosis. Among inflammatory cells, neutrophil infiltration into the brain was significantly reduced in the antibiotics-treated rats. Interestingly, the preventive effect on neutrophil infiltration was already observed immediately after SAH. Next, the immune status of each group before SAH onset was examined. There was no difference in circulating neutrophil counts, but flow cytometry showed a significant decrease in aged neutrophils which exhibit a highly reactive phenotype in the antibiotics-treated rats. Finally, the neuroprotective effect of antibiotics against EBI disappeared when the GM was recolonized.

Conclusions:
Our findings suggest that the GM affects the severity of EBI after SAH by regulating neutrophils. In the future, adjustment of the GM to prevent EBI may become a new strategy in patients who are being followed for cerebral aneurysms.
Abstract WP250: Exosomes Derived From Different Regional Cerebral Endothelial Cells Have Distinct Effects On Adult Rodent Neurogenesis
Authors: Teng Hua , Li Chao , Fan Baoyan , Luo Hao , Zhang Li , Liu Xianshuang , Chopp Michael , Zhang Zhenggang G
Published: February 2022

Introduction:
Exosomes mediate intercellular communication. We tested the hypothesis that exosomes derived from different area cerebral endothelial cells (CECs) have distinct effects on adult neurogenesis.

Methods and Results:
Exosomes were isolated from CECs of cortical (Cor-CEC-exo) and subventricular zone (SVZ-CEC-exo) vessels of non-stroke and stroke rats (n=4/group). Neural stem cells (NSCs) from the non-stroke SVZ were treated with CEC-exo. Proliferation and differentiation of NSCs were measured by BrdU
+
cells and Tuj1
+
neuroblasts. There were no significant differences of size distribution and marker proteins among studied exosomes. Treatment of NSCs with non-stroke Cor-CEC-exo did not significantly change NSC proliferation (35%± 2% vs 31%±2% in control) and neuronal differentiation (5%±2% vs 5%± 0.1% in control). However, treatment of NSCs with non-stoke SVZ-CEC-exo significantly (p<0.05) increased BrdU
+
(42%± 2%) and Tuj1
+
cells (10%± 2%). These data suggest that non-stroke Cor-CEC-exo, but not SVZ-CEC-exo, do not affect neurogenesis. RT-PCR analysis showed that Cor-CEC-exo were enriched in selective miRNAs including miR-203 that is known to negatively regulate NSC proliferation. To study whether miRNAs are involved in the effect of CEC-exo on neurogenesis, we isolated NSCs in which miRNA biogenesis gene, Dicer, was ablated. Compared to wild-type (WT) NSCs, ablation of Dicer led to significant reduction of proliferation (16%±1%) and neuronal differentiation (1%±0.1%). Treatment of Dicer knockout NSCs with Cor- or SVZ-CEC-exo significantly increased BrdU+ (25%±2% or 34%±2%) and TuJ1+ cells (3%±0.1% or 5%±0.1%), suggesting that both Cor- and SVZ-CEC-exo can rescue Dicer knockout impaired neurogenesis. Moreover, both stroke Cor- and SVZ-CEC-exo significantly augmented non-stroke WT NSC proliferation (41%±3% and 51%±4%) and differentiation (9%±0.2% and 16%±0.3).

Conclusion:
Our data demonstrate that under non-stroke condition, Cor-CEC-exo do not promote neurogenesis, while SVZ-CEC-exo enhance neurogenesis. After stroke, both Cor-and SVZ-CEC-exo augment neurogenesis. The effect of CEC-exo on neurogenesis is mediated by miRNAs. This study provides new insight into CEC-exo in mediating neurogenesis.