bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract WP126: Improved Stroke Outcomes Following Implementation of RapidAI Platform at Ascension-Illinois
Authors: Malisch Tim W , Asif Kaiz , Geraghty Scott , Olges Mona , Copeland Karen , Albers Greg
Published: February 2024

Introduction:
The rapid advancement of artificial intelligence (AI) technologies holds promise for improving healthcare outcomes. RapidAI is a software solution that utilizes AI to rapidly analyze imaging data to identify vascular occlusions and salvageable tissue. Physicians receive notifications and can review source images on the Rapid mobile app (RMA).

Methods:
Data for this study were obtained from the Get with the Guidelines Stroke database. The study focused on adult patients (18 years or older) admitted to Alexian Brothers Medical Center in Illinois between 2019-2022 who were diagnosed with acute ischemic stroke. Primary outcomes were the number of AIS patients treated with thrombolysis (IV tPA or IV TNK) and/or mechanical thrombectomy (MT) and time to treatment. Door to MT puncture times for transfer patients were analyzed separately from direct presentation patients. Discharge Modified Rankin score (mRS) was assessed as a secondary clinical outcome.

Results:
This analysis included 1,732 patients, 1,193 prior to installation of the RapidAI platform and 539 after installation of Rapid CTP, CTA, ASPECTS, LVO and RMA. Median door to femoral puncture time for MT cases decreased from 2 hr 28 min to 1 hr 58 min (p=0.012) post-Rapid for non-transfer patients. Door to femoral puncture times for transfer patients were unchanged. MT procedure volume increased from 9.6% to 14.5% (p=0.007). IV tPA/TNK volume and door-to-needle (DTN) times were unchanged; 15% treated with tPA/TNK pre-Rapid and 14% post-Rapid, DTN 48 vs 47 min. There was an improvement in the distribution of discharge mRS scores in post-Rapid patients (p<0.0001).

Discussion:
Following implementation of the AI software platform there was a significant increase in patients treated with MT, faster door to MT times for non-transfer patients, and improved discharge mRS scores. These data support future studies expanding the use of AI technology to improve stroke outcomes.
Abstract WP130: Prevalence and Predictors of Hemorrhagic Foci on Long-Term Follow-Up MRI of Recent Single Subcortical Infarcts
Authors: Jiang Shuai , Shang Wen-Zuo , Cui Jing-Yu , Yan Yu-Ying , Yang Tang , Yi Hu Yi , Cao Le , Yue Xun , Sun Jia-Yu , Wu Bo
Published: February 2024

Background:
Hemorrhagic foci surrounding the lacune in the long-term evolution of recent single subcortical infarcts (RSSIs) remains largely unexplored. We aimed to determine the prevalence, characteristics, and predictors of hemorrhagic foci in patients with RSSI.

Methods:
From a prospective, longitudinal study of RSSIs, we recruited patients who underwent multimodal MRI assessments at baseline and approximately one year after stroke onset. Hemorrhagic foci were identified using susceptibility-weighted imaging (SWI).

Results:
Among 72 patients with RSSI, nearly half (n = 35, 48.6%) had hemorrhagic foci within the index RSSI lesions on follow-up SWI. RSSIs with hemorrhagic foci formation were associated with a longer time to follow-up imaging (median 484 versus 425 days, P = 0.008) and higher likelihood of being located in the anterior circulation compared to those without hemorrhagic foci (100.0% versus 75.7%, P = 0.001). Hemorrhagic foci were also associated with larger lesion size (P < 0.001), higher proportion of cavitation formation (P = 0.042), and poorer functional outcome (P = 0.036). In the subset of RSSIs in the LSA territory, after adjustment for covariates, larger initial lesion volume (OR 1.63, 95% CI 1.06-2.53; P = 0.027) and greater reduction in LSA total length (OR 0.60, 95% CI 0.37-0.97; P = 0.035) were independently associated with hemorrhagic foci formation.

Conclusion:
Half of RSSI patients developed hemorrhagic foci within the lacunes during follow-up SWI. This hemorrhagic feature might represent hemosiderin deposits from a previously thrombosed perforating artery. The pathophysiologic mechanism and clinical implications remain to be determined.
Abstract WP144: Early Initiation of Anticoagulation is Safe After Ischemic Stroke With Atrial Fibrillation, Meta-Analysis and Systemic Review
Authors: Maaz Hafiz M , Chaychi Muhammad , Jamil Muhammad , Akbar Sana , Zakir Faizan A , Fatima Areej , Jamal Muhammad T , Kamal Haris , Ahmed Muhammad K
Published: February 2024

Background:
Large randomized clinical trials have established the superiority of Direct oral anticoagulants (DOACs) over Vitamin-K antagonists in atrial fibrillation (AF) related to Acute Ischemic stroke (AIS). However, the data regarding outcomes of early versus late administration of DOACs is limited, but few recent studies & clinical trials provided some evidence.

Methodology:
The Preferred Reporting Items for Systematic Reviews & Meta-Analyses (PRISMA) standards were followed for this systematic review & meta-analysis". Our search strategy used the Population (AF-related AIS patients taking DOACs), Intervention (early anticoagulation; before 3-4 days), Comparison (late anticoagulation; after 3-4 days), Outcomes & Study type (PICOS) question format. The outcomes of interest were Intracranial hemorrhage (ICH), ischemic stroke & all-cause mortality. The data was pooled using Mantel-Haenszel random effect model & the Higgins I
2
test was used to determine the heterogeneity in each analysis.

Results:
After the database search & study screening, we included 3 prospective cohorts & 1 RCT in our review. All four eligible studies were of good quality (the Newcastle Ottawa Scale & Cochrane Risk of Bias tool 2). Of the 1831 patients who received DOACs in A-F related AIS, 966 were given before 3-4 days & 865 people received them after 3-4 days. The adverse event of ICH (RR 0.65 [95% CI: 0.41 - 1.01] p = 0.68, I
2
= 0%) was similar in both early & late groups. No significant difference in Risk of Ischemic stroke (RR 0.67 [95% CI: 0.36 - 1.24] p = 0.28, I
2
= 22%) & all-cause mortality (RR 0.72 [95% CI: 0.45 - 1.17] p = 0.52, I
2
= 0%) was noted between the two groups.

Conclusion:
Our meta-analysis found that initiating DOACs within 3-4 days of AF-associated stroke is safe & does not affect outcomes such as ICH incidence, stroke recurrence, or all-cause mortality.
Abstract WP148: Implementation of a Hospital Wide Process Improves Rapid Administration of In-Hospital Intravenous Thrombolytics and Endovascular Therapy
Authors: Iordanova Radostina , Sangha Navdeep S , Ajani Zahra , Le Duy , Taleb Shayandokht , Gaffney Denise , shi jiaxiao , Feng Lei , chao kuo , Rex David , Cheng Pamela
Published: February 2024

Background:
The recognition of in-hospital strokes (IHS) and their subsequent interventions remain challenging. IHS do not have guideline-based efficiency metrics established. Only 1 in 5 IHS receive treatment within 60 minutes of symptom recognition time (SRT). We aimed to establish a resident physician-nursing collaborative effort to improve IHS time metrics.

Methods:
We retrospectively compared SRT to bolus time and/or skin puncture time Pre (2010-2016) and Post (2017-2023) implementation of our hospital wide process, which focuses on rapid nursing identification of BEFAST stroke symptoms and notification of the neurology resident physician, who then immediately assesses the patient, validates the last known well time and calls a code stroke if indicated. Chi-square or Fisher’s exact test were used for categorical variables; Wilcoxon’s rank sum test was used for the outcomes of SRT to bolus and SRT to puncture.

Result:
We identified 196 IHS who received emergent treatment: 58 (30%) in Pre and 138 (70%) in Post Intervention (p=0.05). There was no difference in baseline demographics. SRT to thrombolytic administration significantly improved Post Intervention {49 minutes (IQR: 23-268) vs 82 minutes (IQR: 33-220, p<0.05}; Post Intervention SRT to skin puncture time trended towards improvement {90 minutes (IQR: 33-266) vs 110 minutes (IQR: 52-420), p=0.09}. There were no differences in symptomatic intracerebral hemorrhages between the two groups.

Conclusion:
The implementation of a hospital wide process that focuses on a neurology resident physician and nursing collaboration greatly improves IHS SRT to thrombolytic administration time with a trend towards improvement in SRT to skin puncture time.
Abstract WP150: Correlation Between
CYP2C19
Genotype and Platelet Reactivity Units in Patients Receiving Clopidogrel After Acute Ischemic Stroke
Authors: Stone Rachael , Smith Ann , Weko Andrew , Worrall Bradford B
Published: February 2024

Dual antiplatelet therapy (DAPT) with aspirin and clopidogrel is standard of care for secondary prevention in non-cardioembolic minor acute ischemic stroke (AIS) and high-risk transient ischemic attack (TIA). However, clopidogrel is a prodrug metabolized to its active form by the CYP2C19 enzyme and therefore has decreased efficacy in patients with at least one loss-of-function (LOF) allele in the
CYP2C19
gene that encodes the enzyme. The use of ticagrelor over clopidogrel for DAPT improves outcomes in
CYP2C19
LOF carriers; however,
CYP2C19
genotyping is not currently standard practice in the cerebrovascular population. P2Y12 assays that measure P2Y12 receptor-mediated platelet aggregation in platelet reactivity units (PRUs) are more widely accessible, but it is unclear if this assay correlates with
CYP2C19
genotype in this population. Therefore, we aimed to investigate the correlation between
CYP2C19
genotype and PRUs to evaluate PRUs as a potential surrogate biomarker for identifying suboptimal clopidogrel response. We hypothesized that PRUs would be increased in
CYP2C19
LOF carriers compared to non-carriers due to the reduced bioactivation of clopidogrel in patients with decreased CYP2C19 enzymatic function. This prospective, observational study enrolled patients
>
18 years of age presenting with minor AIS or high-risk TIA and discharged from University of Virginia Health on DAPT for secondary stroke prevention. A whole blood sample for P2Y12 assay and
CYP2C19
genotyping was obtained at least 12 hours after a 300 milligram clopidogrel loading dose. The primary outcome was the correlation between PRUs and
CYP2C19
LOF allele carrier status. Of 35 patients genotyped, 27 (77%) subjects self-reported European ancestry, 7 (20%) African ancestry, and 1 (3%) Asian ancestry. Six participants (17%) were found to be LOF carriers. LOF carriers had significantly increased PRUs compared to non-carriers (mean difference +103.7; 95% CI +30.71 to +176.1; p<0.01), indicating diminished pharmacodynamic response to clopidogrel. This suggests that measurement of PRUs via an accessible and established P2Y12 assay may be a viable surrogate biomarker for identifying suboptimal clopidogrel response in the cerebrovascular population.
Abstract WP153: Factors Affecting Length of ICU Stay After Endovascular Thrombectomy for Acute Large Vessel Ischemic Stroke
Authors: Charles Jude H , Torolira Daniel , Castello Juan P , Larinde Oluwagbemiga , Lundy Neva , Peterson Eric , Starke Robert , Yavagal Dileep R , Saini Vasu
Published: February 2024

Introduction:
The advent of endovascular thrombectomy (EVT) for acute large vessel occlusion (LVO) ischemic stroke has reduced the overall ICU length of stay (LoS), especially for patients undergoing successful reperfusion. Prolonged ICU LoS is reported to be associated with worse clinical outcomes, but factors associated with prolonged LoS after MT are not established.

Methods:
A retrospective analysis of 499 patients undergoing EVT at a single large comprehensive stroke center from January 2015 to May 2020 was performed. Demographics, procedure variables, ICU LoS, ICU complications, and modified Rankin scale at discharge were collected. Multiple regression was used to identify independent variables affecting the ICU LoS. Additional analysis using t-test assuming unequal variances was performed for select variables.

Results:
The median age was 72 [61-82], 254 (51%) male & median NIHSS was 16 [10-20]. The average door-to-puncture time was 104 ±28 mins and the average procedure time 43.9 ±28.7. General anesthesia (GA) was administered in 257 (51%) patients. Successful reperfusion (TICI 2c-3) was achieved in 334 (67%) patients. Median ICU LoS was 3 days [1-5]. Patients with mRS 0-2 at discharge (33%) had shorter ICU LoS (2.8 vs 5.7, P<0.001). ASPECTS < 7 (6.9 vs 4.6, P=0.03), use of GA (6.2 vs 3.3 days, P<0.001) and ICU complications such as pulmonary embolism (PE) and pneumonia (10 vs 4 days; p <0.001) significantly increased the ICU LoS. Successful reperfusion significantly reduced ICU LoS (4.2 vs 5.8 days, p=0.015). After adjusting for age, sex, baseline NIHSS and ASPECTS, both the procedure time (b= 0.03, P=0.02) and final TICI score (b= -0.76, P=0.001) were independently associated with prolonged ICU LoS (R2=0.1, F=4, P<0.001).

Conclusion:
Pre-procedural factors such as poor ASPECTS (< 7), procedural factors such as the use of GA, prolonged procedure time, and TICI 0-2b reperfusion, and ICU complications such as pneumonia and PE are associated with prolonged ICU LoS.
Abstract WP159: Chronic Kidney Disease and Risk of Intracerebral Hemorrhage: The Role of Hypertension as a Mediator
Authors: Vanent Kevin N , Rivier Cyprien , Matouk Charles C , Levitt Michael , Leslie-Mazwi Thabele M , Gill Thomas M , Sheth Kevin N , Falcone Guido J
Published: February 2024

Introduction:
Chronic kidney disease (CKD) is a well-established risk factor for spontaneous intracerebral hemorrhage (ICH). However, the biological pathway underlying this association remains unclear. We therefore conducted a phenome-wide association study (PheWAS) to assess for mediators of the association between CKD and ICH risk.

Methods:
We conducted a PheWAS using data from the UK Biobank (UKB), a large cohort study that enrolled over 500,000 Britons aged 40-69. We first developed a polygenic risk score that contained 27 independent (r2 <0.1) genetic risk variants known to be associated with CKD at genome-wide significant levels (p<5x10
-8
). We subsequently tested for associations between this CKD genetic risk score and the 1,840 disease phenotypes available through the UKB baseline assessment. We used a Bonferroni corrected p<2.7x10
-5
as our threshold for significance. For all phenotypes that reached statistical significance in the PheWAS, we obtained summary results from previously published genome-wide association studies and implemented multivariable Mendelian Randomization (MR) to evaluate the proportion of the total effect of CKD on ICH risk mediated through these phenotypes. The indirect effect of CKD on ICH risk via mediators was calculated by subtracting the direct effect of CKD obtained from multivariable MR from the total effect of CKD obtained from univariable MR.

Results:
Excluding renal-related diseases, hypertension was the only significant phenotype in the PheWAS (p=3.2x10
-21
). Genetically determined CKD was associated with a total increase in ICH risk of 38% in univariable MR (OR 1.38; 95% CI 1.12-1.71; p=0.002). This association was reduced to a 19% increase in ICH risk after adjusting for hypertension in multivariable MR (OR 1.19; 95% CI 1.03-1.39; p=0.021). The proportion of the total effect of CKD on ICH risk mediated through hypertension was estimated to be 55%.

Conclusions:
Hypertension accounts for approximately 55% of the total effect of CKD on ICH risk in genetic analyses. This aligns with existing knowledge that CKD worsens hypertension by causing renal retention of sodium and increased sympathetic activity. Further studies are needed to identify other pathways that mediate the remaining effect of CKD on ICH risk.
Abstract WP16: Thrombolysis in Wake-Up Stroke Improves Outcomes, Reduces Cost, and Reverses ADC Lesions
Authors: Rana Maheen , Tung Glenn A , Burton Tina M , Kelly Mary , Shu Liqi , Jayaraman Mahesh , Torabi Radmehr , Moldovan Krisztina , Stretz Christoph , Collins Scott , Furie Karen L , Yaghi Shadi
Published: February 2024

Introduction:
Trials using advanced imaging have shown a benefit from intravenous thrombolysis in patients with wake-up stroke, but real-world data is limited. This study presents data on outcomes in patients presenting with wake-up stroke at a comprehensive stroke center comparing those who received thrombolysis to those who did not.

Methods:
In February 2022, our institution implemented a wake-up stroke protocol utilizing emergent MRI-based evaluation for possible thrombolysis. The protocol combines clinical criteria (suspected ischemic stroke with disabling neurologic deficits; last known normal within 12 hours; time from symptom discovery to arrival within 4.5 hours) and imaging criteria (absence of proximal large vessel occlusion; FLAIR-DWI mismatch; signal intensity ratio < 1.15 in those able to receive perfusion imaging). In this study, we compared discharge outcomes and hospital length of stay for patients with ischemic stroke selected for wake-up protocol with vs. without thrombolytic therapy. In addition, we assessed the proportion of patients with reversibility of diffusion restriction, defined as a decrease in infarct volume on ADC sequence between the pre-treatment to 24-hour post-treatment MRI.

Results:
Between February 2022 & June 2023, there were 31 wake-up stroke activations (~2 per month). Median admission NIHSS was 6. 30% had medium or distal vessel occlusions. 71% of stroke activations had a final diagnosis of ischemic stroke; 32% of cases were eligible per protocol and treated with thrombolysis. Compared to patients diagnosed with ischemic stroke but not eligible for treatment, those treated with thrombolysis were more likely to be discharged home (70% vs. 17%, p = 0.02) and had a shorter hospital stay by ~1.5 days (mean LOS 3.6 days vs. 4.8 days; median LOS 3 days vs. 4.5 days; p <0.01). ADC reversibility was demonstrated in ~30% of patients who underwent thrombolysis.

Conclusions:
Intravenous thrombolysis for patients presenting with wake-up stroke was feasible, improved outcomes, and reduced potential cost. It also demonstrated ADC reversibility in 30% of cases. Further steps are needed to increase availability of emergent MRI and optimize door to thrombolysis times in order to streamline access for potential treatment.
Abstract WP161: Characterizing the Underlying Microangiopathy of Deep Cerebellar Intracerebral Hemorrhage
Authors: Das Alvin S , Abramovitz Fouks Avia , Gokcal Elif , Rotschild Ofer , Pasi Marco , Regenhardt Robert W , Goldstein Joshua N , Viswanathan Anand , Rosand Jonathan , Greenberg Steven , Gurol Edip M
Published: February 2024

Introduction:
Superficial (gray matter, vermis) cerebellar intracerebral hemorrhage (cICH) is associated with strictly lobar supratentorial cerebral microbleeds—a strong marker for cerebral amyloid angiopathy. However, for deep (white matter, deep nuclei, cerebellar peduncle) cICH, it is unclear whether hypertensive cerebral small vessel disease (HTN-cSVD) is the underlying microangiopathy.

Hypothesis:
We hypothesized that left ventricular hypertrophy (LVH), a marker for hypertensive end-organ damage, and non-hemorrhagic imaging markers of HTN-cSVD such as peri-basal ganglia (BG) white matter hyperintensity (WMH) pattern, deep lacunes, and severe BG enlarged perivascular spaces (EPVS) would be associated with deep vs. superficial cICH.

Methods:
Brain MRI scans from a prospective database of consecutive non-traumatic ICH patients admitted to a single referral center (2003 to 2019) were analyzed for the presence of cerebral microbleeds (CMBs) and non-hemorrhagic neuroimaging markers. The presence of clinical risk factors, LVH, and neuroimaging markers were compared between patients with deep and superficial cICH in univariate and multivariable models.

Results:
Of 1,791 patients with spontaneous ICH, 129 (7%) were found to have cICH (mean age 73±12 years, 46% female). Of these, 83 (64%) patients had deep cICH and 46 (36%) patients had superficial cICH. Hypertension (94% vs. 67%,
p
< 0.01) and LVH (60% vs. 28%,
p
< 0.01) were more common among patients with deep vs. superficial cICH. Among those who received a brain MRI (74%), the frequency of peri-BG WMH pattern (24% vs. 5%,
p
= 0.02), deep lacunes (59% vs. 14%,
p
< 0.01), severe BG EPVS (27% vs. 3%,
p
< 0.01), deep CMBs (51% vs. 16%,
p
< 0.01), and mixed location CMBs (37% vs. 11%,
p
< 0.01) was greater among patients with deep cICH compared to superficial cICH. When these variables were entered into a multivariable regression model, LVH (OR 3.10, 95% CI [1.07-8.97],
p
= 0.04) and deep lacunes (OR 4.38, 95% CI [1.25-15.31],
p
= 0.02) remained significantly associated with deep cICH.

Conclusions:
Because supratentorial HTN-cSVD imaging markers are common in deep cICH, and deep lacunes and LVH are independently associated with deep cICH, it is likely that HTN-cSVD is the underlying microangiopathy of deep cICH.
Abstract WP167: Clinical Characteristics and Outcomes of Mixed Cerebral Small Vessel Disease According to the CLAS-ICH Classification
Authors: Ogawa Atsushi , Miwa Kaori , Shiozawa Masayuki , Inutsuka Ryoko , Usui Ryo , Arakaki Yoshito , Kamogawa Naruhiko , Yoshimura Sohei , Toyoda Kazunori , Ihara Masafumi , Koga Masatoshi
Published: February 2024

Objectives:
Mixed location intracerebral hemorrhages/ microbleeds (CMBs) (mixed ICH) is referred to as potential hypertensive arteriolosclerosis/cerebral amyloid angiopathy (CAA) combination, reflecting small vessel disease (SVD) burden. We assess the clinical features in patients with mixed ICH.

Methods:
We utilized data from a prospective registry, which consecutively enrolled patients diagnosed with acute ICH between January 2011 and December 2021. Patients with ICH were classified into subtypes according to the CLAS-ICH classification: hypertensive arteriolosclerosis ([HTN]-ICH), CAA-ICH, mixed ICH, genetic SVD, and secondary causes. The clinical data of patients with mixed ICH were compared to those with HTN-ICH or CAA-ICH. The outcome measure was unfavorable functional outcomes defined as mRS score of 5-6 at 90-day.

Results:
Of 2127 patients with ICH (mean age 70±13 years, 57% male), 1374 (65%) had HTN-ICH, 141 (6%) had CAA-ICH, 409 (19%) had mixed ICH, none (0%) had genetic SVD, 203 (10%) had secondary causes. Patients with mixed ICH were older (75±11 vs. 69±13 years) and had a high frequency of CMBs (68% vs. 25%), had lower initial SBP (176±32 vs. 184±30 mmHg) and initial NIHSS (12 [4-21] vs. 14 [7-23]) and more hematoma volume (17 [6–52] vs. 11 [4–24] ml), compared to those with HTN-ICH (all P<0.001). There were no significant differences in hypertension, dyslipidemia, and diabetes. When comparing patients with mixed ICH to those with CAA-ICH, they were younger (75±11 vs. 78±8 years) and had a high frequency of male (54% vs 33%), hypertension (95% vs. 36%) and diabetes (14% vs. 5%) and had higher initial SBP (176 ± 32 vs. 160 ± 29 mmHg) and less hematoma volume (17 [6–52] vs. 44 [18–84] ml)(all P<0.001). There was no significant difference in unfavorable outcomes between mixed ICH and HTN-ICH (32% vs. 31%, p>0.1), while the outcomes for mixed ICH were lower than those for CAA-ICH (32% vs. 44%, p=0.004). In multivariate analysis adjusting for covariates, there was no significant difference in unfavorable outcomes between mixed SVD-ICH and CAA-ICH (odds ratio 1.19 [95% CI, 0.66–2.13]).

Conclusions:
Mixed ICH harbors similar features of hypertensive SVD rather than CAA. The rates of disability and mortality were comparable across the groups.
Abstract WP169: Thromboelastography as a Biomarker of Emergent Direct-Acting Oral Anticoagulant Reversal With Prothrombin Complex Concentrates for Intracranial Hemorrhage
Authors: Zepeski Anne , Faine Brett , Ghannam Malik , Olalde Heena M , Mohr Nicholas , Leira Enrique C
Published: February 2024

Prothrombin complex concentrates (PCCs) are used to emergently reverse direct-acting oral anticoagulant (DOAC) activity. PCCs are recommended as an alternative to recombinant coagulation factor-Xa to reverse anticoagulation activity of apixaban or rivaroxaban. Measuring the degree of anticoagulation reversal in this population is limited. Thromboelastography (TEG) has been used to detect the presence of DOAC plasma levels in patients chronically taking a DOAC but has not been utilized to measure the effect on anticoagulant activity after PCC administration. We aimed to determine whether TEG R-time is useful in detecting the impact of PCC administration on anticoagulation activity in patients with anti-factor Xa-associated intracranial hemorrhage (ICH). We prospectively evaluated the utility of TEG to assess anticoagulation activity after factor Xa inhibitor reversal with 4-factor PCC. Adults with ICH taking apixaban or rivaroxaban were included. Patients were excluded if their last known dose of anticoagulation was >48 hours prior to arrival, had known apixaban or rivaroxaban blood levels <20 ng/mL, or had the following comorbidities: hepatic failure, hereditary disorders of hemostasis, polytrauma, or pregnancy. TEG samples were collected before PCC administration (if available), and 0.5, 12, and 24 hours after PCC administration. Thirty-one patients were enrolled between November 2022 and August 2023. The median PCC dose was 24.5 units/kg (IQR 20.3-26.9 units/kg; n=29). Nine patients received anticoagulation reversal after baseline TEG collection; the remainder received anticoagulation reversal at transferring facilities. Baseline R-time was negatively correlated with time since last dose of DOAC (n=9). A median decrease in R-time of 0.8 minutes after PCC (IQR -1.6 - 0.3; n=8) was found in patients with baseline TEG collection. R-time rebounded by a median of 0.75 minutes (IQR 0.2-2.0; n=8) from 0.5 hours to 12 hours after PCC administration (n=8). TEG R-time, a measure that inversely correlates with the degree of anticoagulant effect, rapidly decreases after PCC in patients taking DOACs that present with acute ICH. TEG R-time rebounds 12 hours after PCC administration. TEG-R time may be a useful biomarker in DOAC reversal with PCC.
Abstract WP170: Patients With Cerebral Microbleeds Are More Likely to Have Poor Collaterals at the Time of Mechanical Thrombectomy
Authors: Wolcott Zoe , Anisetti Bhrugun , Shourav Manjurul , Meschia James F , Lin Michelle P
Published: February 2024

Introduction:
Collateral cerebrovasculature is important for the survival of penumbral tissue in patients with large vessel occlusive (LVO) stroke, and adequate collateralization is associated with favorable outcomes. The presence of cerebral microbleeds (CMB) have been implicated in vessel wall remodeling and impaired vasoreactivity. We investigated whether the presence of deep and/or lobar CMB predicts poor collateral recruitment in patients with LVO stroke who underwent thrombectomy (MT).

Methods:
We performed a retrospective, single-center study of adults who presented with LVO stroke and had MT between January 2012-June 2020. CT angiography of head prior to MT was used to assess collateral status with poor status defined as ≤50% filling and good status as >50% filling. CMBs were assessed using T2*-weighted gradient echo or susceptibility weighted magnetic resonance images. Location of CMB was further characterized as deep vs. lobar using consensus definitions. Poor stroke outcome was defined as modified Rankin Scale (mRS) ≥3 at 90 days. Multivariable logistic regressions were performed to evaluate the associations between CMB, CMB types (lobar, deep, lobar+deep) and poor collaterals after adjusting for vascular risk factors.

Results:
Consecutive 151 subjects were included (mean age 68±15 years, 47% women), with a median NIHSS of 18. CMB were identified in 57 subjects (37.4%). Of these, 20.5% had lobar CMB, 5.3% had deep CMB and 11.9% had combined lobar & deep CMB. Patients with CMB had higher odds of having poor collaterals compared to those without CMB (OR 1.56, 95% CI 1.09-2.23, P=0.015). The association of CMB with poor collaterals was strongest in patients with combined lobar & deep CMB (OR 4.78, 95% CI 1.43-15.93, P=0.011), compared with those with exclusively deep CMB (OR 2.78, 95% CI 0.44-17.62, P=0.278) or lobar CMB (OR 0.52, 95% CI 0.19-1.38, P=0.188). Patients with poor collaterals were more likely to have poor outcome compared with those with good collaterals (48.4% vs. 31.0%, P=0.03).

Conclusion:
Cerebral microbleeds are independently associated with poor collateral recruitment when adjusted for traditional vascular risk factors. Further study is warranted to elucidate the differential effects of CMB types on collateral recruitment.
Abstract WP195: The Impact of Tortuosity on Microwire Torquability
Authors: Molaie Amir M , Sakuta Kenichi , Hanaoka Yoshiki , Watanabe Hirobumi , Saber Hamidreza , Imahori Taichiro , Tateshima Satoshi , Kaneko Naoki
Published: February 2024

Introduction:
Navigation of a microguidewire through the intracranial vasculature is crucial for the success and safety of neuroendovascular procedures. Its navigation is influenced by a combination of patient factors, such as vessel tortuosity, and device factors, such as microwire torquability. In this study, we compared the torquability of microwires in two vascular models of differing tortuosity.

Methods:
We tested torquability of three 0.014” nitinol microwires (Synchro Select Soft, Standard, or Support, Stryker Neurovascular, Fremont, CA) docked in either a moderate tortuosity silicone flow model of the middle cerebral artery (MCA), or a severe tortuosity model of the anterior cerebral artery (ACA). Tortuosity was determined by measuring the length of the centerline/straight length (MCA 1.28, ACA 2.22). The microwires were rotated proximally at a constant rate of 180 degrees per second, seven times clockwise and seven times counterclockwise. Rotation at the distal tip was quantified by measuring the change in angle every 0.2 seconds over 6 seconds. To quantify the deviation of distal tip motion from the ideal, the difference between the distal degrees measured and the proximal degrees rotated were summed and compared between wires.

Results:
In the severe tortuosity ACA model, the distal tip of the stiffer Support wire displayed significantly larger deviation from ideal than either the Standard (p<0.0001) or Soft (p<0.0001) wires. There was no significant difference amongst the three wires in the moderate tortuosity MCA model (p=0.598).

Discussion:
Our results demonstrated that increased vessel tortuosity decreased the torquability of the stiffer Support microwire. This was observed as “whip” motions of the Support wire in the severe tortuosity model, likely due to its higher bending rigidity. In cases of distal vessel selection or tortuous vasculature, our results suggest a Soft or Standard microwire should be utilized in place of a stiff wire.
Abstract WP197: Poor Venous Outflow is Associated With Ischemic Core Growth During Transfer in Acute Ischemic Stroke Patients With a Large Vessel Occlusion
Authors: Zamarud Aroosa , Seners Pierre , Mlynash Michael , Wouters Anke , Lugo Leonel , Faizy Tobias , Lansberg Maarten G , Albers Gregory W , Heit Jeremy J
Published: February 2024

Introduction:
Thrombectomy is an effective therapy for the treatment of acute ischemic stroke due to large vessel occlusion (AIS-LVO). Patients with small ischemic cores have the most favorable outcomes after thrombectomy, and core growth during the transfer from a primary to a comprehensive stroke center (PSC to CSC) can lead to worse outcomes. We determined if poor venous outflow (VO) prior to transfer to a CSC predicts ischemic core growth in AIS-LVO.

Methods:
AIS-LVO patients in the prospective CRISP2 study who had a CTA and CT perfusion (CTP) at a PSC and a follow-up CTP or MRI immediately after transfer to the CSC were screened for enrollment. VO was measured on CTA at the PSC using cortical venous opacification score (COVES). COVES 0-2 was defined as unfavorable VO (VO-) and 3-6 was defined as favorable (VO+). Ischemic core was determined on CTP at the PSC and DWI MRI or CTP at the CSC. The primary outcome was inter-hospital ischemic core growth rate defined as a ratio between core growth and time between scans.

Results:
174 patients were included; 64% had VO+ and 36% had VO-. VO- patients had larger baseline ischemic core volumes (median 10.5 [IQR 0-23.3] vs 0 [IQR 0-11] ml, p=0.006) and worse CTA collaterals (TAN median 1.82 [IQR 0-3] vs 2.26 [IQR 1-3], p=0.0002). VO- experienced greater ischemic core growth (median 19.6 ml [IQR 2.5-38] vs 8.8 ml [IQR 1.5-21.7], p=0.005) and higher growth rate (median 5.7 ml/hr [IQR 1.4-13.4] vs 2.8 ml/hr [IQR 0.4-7.5], p=0.007) during transfer as described in

Figure 1

.

Conclusions:
In AIS-LVO patients, VO- prior to transfer to a comprehensive stroke center correlated with increased ischemic core growth and more rapid core growth rates. These results have implications for neuroprotection trial design.
Abstract WP203: Prediction of Outcome After Endovascular Therapy for Acute Ischemic Stroke: A Machine Learning Approach From Japan Stroke Data Bank
Authors: Yoshie Tomohide , Yoshimura Sohei , Wada Shinichi , Sakuraba Makino , Suzuki Takayuki , Yoko Sumita , Miwa Kaori , Miyamoto Yoshihiro , Toyoda Kazunori , Koga Masatoshi
Published: February 2024

Introduction:
Previous studies have demonstrated the predictive capabilities of machine learning (ML) models using clinical, imaging, and angiographic characteristics in determining the clinical outcome of patients undergoing endovascular treatment for acute ischemic stroke. We aimed to analyze a large-scale stroke registry and develop an ML model that solely utilizes clinical characteristics, without the need for imaging or angiographic data, to predict the outcome of patients treated with endovascular therapy for acute ischemic stroke.

Methods:
We conducted our analysis using data from the Japan Stroke Data Bank, a nationwide acute stroke registry containing individual patient data. A total of 4353 patients who underwent endovascular treatment for acute ischemic stroke between January 2016 and December 2020 were included in the study. Patient data from 2016 to 2019 were used as the derivation cohort, while data from 2020 were used as the validation cohort. An ML models were trained on 70% of the patients randomly selected from the derivation cohort and tested on the remaining 30%. The input variables for the ML models consisted of 138 clinical characteristics including neurological examination findings. Imaging, angiographic, and laboratory data were not utilized in the ML process. The primary outcome measure was good outcome at discharge, defined as a modified Rankin Scale score of 0-2.

Results:
Of the 4353 patients included in the study, 1520 patients (34.9%) achieved good outcome. The area under the curve for predicting good outcome was 0.76 for the test set in the derivation cohort and 0.78 for the validation cohort. The SHAP summary plot revealed that the top five major predictive contributors for good outcomes were pre-stroke modified Rankin Scale score, level of consciousness, age, stroke classification, and NIHSS score.

Conclusions:
Our findings demonstrate that an ML model utilizing solely clinical characteristics, without the inclusion of imaging or angiographic data, can accurately predict good outcomes at discharge for acute stroke patients treated with endovascular therapy. This approach has the potential to provide an aid in clinical decision-making before imaging examination.
Abstract WP213: Exploring Contrast Extravasation and Associated Variables in Acute Ischemic Stroke Patients After Mechanical Thrombectomy: Single Center Experience
Authors: Khasiyev Farid , Kaur Gunjanpreet , Rodriguez Wilson , Miremadi Brian B , Edgell Randall C , Linares Guillermo , Christopher Kara
Published: February 2024

Introduction:
Head CT hyperdensity (HCH) commonly follows mechanical thrombectomy (MT) for large vessel occlusion (LVO), often due to contrast extravasation (CE) or intracerebral hemorrhage (ICH). Given the 20-88% prevalence in studies, understanding associated variables is crucial for outcomes. Risk factors for ICH after MT are studied, but CE understanding is lacking. We investigated CE occurrence variables and their impact on outcomes.

Methods:
We retrospectively analyzed data from 164 patients (mean age 65 years, 51% men, 59% White) with LVO who underwent MT in our center (between 2019-2022) with initial and repeat post-MT CT scans within a 24-hour window. CE was defined as the disappearance or reduction of HCH on repeat CT within 24 hours; those with both CE and ICH were excluded. We investigated demographic information, risk factors, lab values, procedural, and neurological outcome data. Parametric and non-parametric tests compared variables between CE and ICH. Adjusted odds ratios (aOR) were computed through multivariate logistic regression to evaluate the association of CE with the variables.

Results:
HCH was reported in 56.1% (92 out of 164) of patients in our cohort. CE and ICH were detected in 34 (20.4%) and 58 (35.4%) patients. In unadjusted models, our patients with CE had higher low-density lipoprotein (LDL) levels (111 mg/dL vs. 80 mg/dL, p=0.04) and lower complete reperfusion score (29.4% vs. 55.2%, p=0.02) (Table 1). Multivariate logistic regression analysis demonstrated a higher aOR (1.03, 95%CI 1-1.06, p=0.03) of LDL in patients with CE (Table 2).

Conclusion:
Our findings revealed a notable association between CE and higher LDL levels. Elevated LDL levels are often linked to systemic inflammation, endothelial dysfunction, vascular changes, and disruptions in the blood-brain barrier, increasing the likelihood of CE. This association prompts further investigation into the underlying pathophysiology of CE.
Abstract WP233: Histone Lactylation in Neuronal Mitochondria Fission: Implications for Stress-Exacerbated Ischemic Stroke Outcomes
Authors: Zhu Yuequan , Geng Xiaokun , Li Fengwu , Ding Yuchuan
Published: February 2024

Introduction:
Mental stress was linked with adverse outcomes following ischemic stroke. Accumulation of lactate due to mental stress is well-documented, especially in skeletal muscles. Importantly, lactate serves as a key substrate for lactylation, a novel post-translational protein modification, which triggers mitochondrial fission. This study investigates the pivotal role of histone lactylation in driving neuronal mitochondrial fission, which may amplify the detrimental outcomes of stroke under mental stress.

Methods:
A total of 120 C57BL/6J mice were divided into four groups: control, chronic restraint stress (CRS), lactylationantagonist (C646, 10mg/kg, i.p.) and C646+CRS. CRS for mice was induced in a 50mL tube for 6 hours per day for consecutive 28 days. On the day 29
th
, Western blot was applied to detect the expression of fission related proteins (DRP1, MFF and FIS1). The effects of lactylation on mitochondria function was determined through JC-1 and mitoSOX™ staining by adding exogenous lactate (10mM) and C646 (20mM) in neuronal cells. The stressed mice then were subjected to 45 minute-middle-cerebral -artery-occlusion (MCAO). At 6 and 24 hours of reperfusion, apoptotic cell death and apoptotic proteins (Bcl-2, BAX and cleaved caspase-3) were measured by TUNEL and Western blot. Infarct volume and neurological deficits were determined by TTC staining and scoring systems at 48 hours of reperfusion.

Results:
CRS aggravated ischemic injury and apoptosis after stroke. C646, a lactylation antagonist, significantly decreased protein expressions of DRP1, MFF and FIS1 and reversed CRS-associated stroke injury. Furthermore, mitochondria membrane potential (MMP) was decreased and ROS was increased upon exogenous lactate in neuronal cells, accompanied by increased mitochondria fission. Again, C646 reverses mitochondria dysfunction and fission.

Conclusions:
Our results shed light on how CRS intensifies the ischemic damage post-stroke. Central mechanism is histone lactylation which triggers neuronal mitochondria fission, thereby impacting the outcomes related to stress-associated stroke. Lactylation antagonists offer promising avenues for therapeutic interventions, mitigating the adverse effects of stress on stroke outcomes.
Abstract WP235: Cannabis Use Disorder in Elderly Stroke Survivors (≥65 Years) Elevates the Risk of Stroke Recurrence: An Analysis From the National Inpatient Sample (2016-2019)
Authors: Mahadevan Arankesh , Valluri Jnana Pramod , Annam Saketh , Gondi Yasho , Rajbhandari Pranaya , Lakkimsetti Mohit , Kaur Parvinder , Raj Rohan , Tullimalli Immanuel R , Anil Peethambar Gowri , Desai Rupak
Published: February 2024

Introduction:
Amid the rising prevalence of cannabis use disorder (CUD) in older adults and with surveys reporting ~85% of overlapping use for medicinal and recreational purposes in American cannabis users, the link between CUD and stroke is paramount. This study explores the risk of recurrent acute ischemic stroke (AIS) or hemorrhagic stroke (HS) in CUD while also evaluating the effects of coexisting substance abuse and mental health conditions.

Methods:
Elderly (age >65 years) stroke survivors were identified using ICD-10 codes from the National Inpatient Sample (2016-2019) and categorized based on the presence or absence of CUD and recurrent AIS or HS. Multivariable statistical methods assessed demographics, comorbidities, and temporal trends.

Results:
Out of 5,284,119 elderly stroke survivors, 16,820 (0.3%) had CUD and presented younger (median age: 69 vs. 79), predominantly male (68.8% vs. 45.1%), with a larger representation of black individuals (30.8% vs. 12.8%), and higher prevalence in the lowest income quartile (39.7% vs. 28.4%). Comorbidities like diabetes, hyperlipidemia, obesity, and hypothyroidism were less common in CUD patients, but substance abuse and mental health disorders were more prevalent. From 2016 to 2019, CUD among stroke survivors rose from 0.24% to 0.37%. The uptrend was observed across genders, racial groups (except Asians and Native Americans), income quartiles, hospital regions, and in cohorts with and without anxiety, depression, alcohol abuse, and tobacco use. Additionally, the recurrence of AIS decreased from 5.32% to 5.13% in the non-CUD group. After adjustment, the odds of recurrent AIS in the CUD cohort was 1.56 (95% CI:1.35-1.79), and for any stroke type (AIS or HS) 1.44 (95% CI:1.26-1.65).

Conclusion:
Elderly stroke survivors with concurrent CUD have a 56% increased risk of recurrent AIS and a 44% heightened risk for AIS or HS. The growing prevalence of CUD in this demographic underscores it's escalating clinical significance.
Abstract WP246: CHA
2
DS
2
-VASC Score Predicts Outcomes After a Stroke or Transient Ischemic Attack
Authors: Olaiya Muideen , Song Zheng , Andrew Nadine , Dalli Lachlan , Ung David , Kim Joosup , Cadilhac Dominique A , Kilkenny Monique F
Published: February 2024

Introduction:
The CHA
2
DS
2
-VASC score is used to predict stroke in people with atrial fibrillation (AF). We determined the utility of this score for predicting outcomes within one-year post-stroke/TIA.

Methods:
Analysis of adults with acute stroke/TIA (2012-2016) using linked data from the Australian Stroke Clinical Registry and administrative datasets (pharmaceutical, hospital, Medicare), as part of the PRECISE study. CHA
2
DS
2
-VASC score (ranging from 0-9) was estimated based on comorbidities documented in hospital data as of the time of acute stroke/TIA. Outcomes included health-related quality of life (HRQoL) at 90-180 days post-stroke/TIA; and all-cause mortality and hospital readmissions (all-cause, cardiovascular disease) within 1 year post-stroke/TIA. HRQoL was assessed using the EuroQoL 5D-3L visual analogue scale (VAS) score, ranging from 0 (worst health) - 100 (best health), and across health domains (mobility, self-care, usual activities, pain/discomfort, anxiety/depression). Regression models were used to determine associations with outcomes, with risk estimates were expressed per 1-point increase in CHA
2
DS
2
-VASC score, and adjusted for covariates (e.g. use of medications) and interaction with AF history.

Results:
Of 12,613 eligible participants (median age 74 years; 44% female; 26% AF history), the median CHA
2
DS
2
-VASC score was 4 (i.e., high risk; interquartile range 3-6). In multivariable models, greater CHA
2
DS
2
-VASC score was associated with increased rates of mortality (hazard ratio [HR] 1.28 95% CI 1.23-1.33) in people with AF history only. Regardless of AF history, greater CHA
2
DS
2
-VASC score was associated with reduced VAS scores (by -1.57, 95% CI -1.99, -1.15), and increased odds of reporting problems in each HRQoL domain, ranging from odds ratio of 1.36 (95% CI 1.31-1.41) for mobility to 1.05 (95% CI 1.02-1.09) for anxiety/depression. Greater CHA
2
DS
2
-VASC score was also associated with increased rates of readmission for all causes (HR 1.11, 95% CI 1.08-1.14) or cardiovascular causes (HR 1.10; 95% CI 1.05-1.15).

Conclusion:
CHA
2
DS
2
-VASC score as of the time of acute stroke/TIA is associated with worse long-term outcomes, including HRQoL, within 1 year, and may be useful for risk stratification post-stroke/TIA.
Abstract WP249: Risk for Ischemic and Hemorrhagic Stroke is Increased in Veterans Exposed to Agent Orange and Those With Myeloproliferative Neoplasms
Authors: Mathur Natasha , Tiu Andrew , McKinnell Zoe , Gill Puneet , Antonio Martha , Liu Shanshan , Diao Guoqing , Subrahmanyam Ramesh , Kessler Craig M , Jain Maneesh R
Published: February 2024

Agent Orange (AO) is a dioxin containing defoliant and carcinogen used in the Korean and Vietnam War. There is limited evidence of the association between AO exposure among Veterans and stroke. Stroke is not yet part of the list of presumptive conditions according to the Promise to Address Comprehensive Toxics (PACT) Act which provides Veterans and their survivors disability compensation for conditions arising from exposure to AO. Myeloproliferative Neoplasms (MPN) are uncommon etiologies of stroke but whether AO exposure increases incidence of stroke in MPN has not been described.

Utilizing the Veterans Affairs Informatics and Computing Infrastructure (VINCI) database, a case-control study was performed from 1/1/2006 – 1/26/2023 on the Veterans from Illinois, the state most representative of the US population. ICD-9 and -10 codes identified Veterans with stroke and MPN. AO exposure was verified on the Veterans’ service duration and location. Qualitative data were compared by chi-square tests.

Among 586,555 Veterans from Illinois, there were 15,455 ischemic stroke (IS), 1,593 hemorrhagic stroke (HS), 2,752 MPN, and 59,393 with AO exposure. Among MPNs, there were 237 IS (41 with AO) and 26 HS (3 with AO). IS and HS were associated with AO exposure, OR 1.34 95% CI 1.28-1.41, p<0.0001, and OR 1.20 95% CI 1.03-1.39, p=0.02, respectively. MPN is associated with IS and HS, OR 3.52, 95% CI 3.08-4.03, and OR 3.54, 95% CI 2.4-5.23, both p<0.0001, respectively. There is no significant association with AO exposure among Veterans with MPN with stroke. Among non-MPN Veterans with AO exposure, there was an earlier median age of IS and HS, 67 vs. 70 and 67 vs. 71, both p<0.0001. There was no difference in median age of stroke among MPN Veterans with or without AO exposure. There were no differences with rates of hypertension, hyperlipidemia, diabetes, smoking, heart failure, and pulmonary hypertension among MPN Veterans with stroke with and without AO exposure.

In conclusion, there is an association of AO exposure with IS and HS with an earlier onset among those exposed. There is a strong association between MPN and stroke independent of AO exposure. The biologic plausibility of endothelial dysfunction and accelerated atherosclerosis from AO exposure warrants further investigation.