bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract TP265: Far-Forward Stroke Care: Parallel Processing in the Prehospital Environment May Achieve Door-to-Needle Times of Less Than 15 Minutes on a Mobile Stroke Treatment Unit
Authors: Zammit Christopher , Gallagher Sarah , Burgett Jason , Grassman Christopher , L'Esperance Joshua , Pilcher Webster , Benesch Curtis , Bhalla Tarun
Published: June 2021

Introduction:
The time from 911 activation (i.e. alarm) to administration of intravenous (IV) alteplase in acute ischemic stroke is associated with functional, patient centered-outcomes. Mobile stroke treatment units (MSTUs) have emerged as a stroke system tool that may hasten treatment times. Optimal workflows on MSTUs remain to fully elucidated.

Methods:
Retrospective review of a QA database of patients treated on a MSTU with door-to-needle-times (DTN) of </= 15 minutes to describe workflows and team dynamics that were associated with expeditious treatment.

Results:
In October of 2018 the University of Rochester Medical Center launched a MSTU, initially operating on Monday through Friday in the city of Rochester from 8am until 4 pm. Over the initial 3 months, there were 96 MSTU responses leading to 54 transported patients, 3 of which were treated with IV alteplase. One patient with an initial NIHSS of 17 was treated with IV alteplase within 9 minutes of reaching the MSTU door. Workflow elements felt to hasten treatment included registration of the patient in the electronic health record (EHR) prior to the patient reaching the MSTU and enabling the telestroke provider to listen to the initial history and physical being performed by the MSTU RN at the scene. The later is accomplished by using a telestroke iPhone application that allows for a “3-way-call” between the MSTU RN, the MSTU, and the telestroke provider. The MSTU RN wears a Bluetooth earpiece that captures the conversation with the patient, witnesses on scene, and initial EMS responders and enables the MSTU RN to summarizes key history and exam findings, vitals, and blood glucose results while keeping their hands available for patient care. Simultaneously, the telestroke provider reviews the patient’s chart in the EHR for alteplase contraindications, prior imaging results, and pertinent medical history.

Conclusion:
Registering the patient in the EHR and integrating the telestroke provider into the initial patient assessment at the scene in the prehospital setting may allow for consistent door to needle times of < 15 minutes on MSTUs, which may further improve patient outcomes.
Abstract TP267: Plasminogen Inhances the Process of Angiogenesis After Cerebral Ischemia in Mice via Thrombospondin
Authors: Fang Jinghuan , Chopp Michael , Zhang Li , Wang Fengjie , Liu Zhongwu , He Li
Published: June 2021

Background:
Stroke is the first cause of death in Chinese residents. Plasminogen playes an important role in the process of anigiogenesis. But its specific mechanism of regulating angiogenesis after stroke is not clear.

Method:
We used wild-type (WT) mice and plasminogen knockout (KO) mice to conduct a permanent middle cerebral artery infarction model (MCAo). At different time points after operation we performed function test; used FITC to measure brain vascular distribution; used western-blot to detect the expression of TSP after MCAo. We used the cerebral vascular endothelial cells for tubeformation. All collected data were processed by corresponding image software, and the results were statistically analyzed by variance analysis or t test.

Results:
(1) The total length of capillary formation of cerebral vascular endothelial cells in group KO mice was less than that in group WT.(Figure 1) (2) The loss of motor sensory function in group WT was always less than that in group KO. (Figure 2) (3) After MCAo, the blood vessel density in the two groups of mice increased with time, and the density of blood vessels in the WT group was greater than that of the KO group. (Figure 3 ) (4) After MCAo, the levels of TSP-1 and TSP-2 in the cerebral tissue of KO and WT mice were higher than those in the contralateral brain. At the same time, the expression of TSP-1 and TSP-2 in the infarct lateral brain tissue of group KO was higher than that in group WT. (Figure 4)

Conclusion:
The lack of plasminogen can regulate the expression of TSP-1 and TSP-2 after ischemic stroke, thereby inhibiting the angiogenesis process of brain tissue after cerebral ischemia which leads to poor functional prognosis. stroke.
Abstract TP270: Adipose Derived Mesenchymal Stem Cells Reduce Autophagic Flux After Ischemic Stroke in Mice via Extracellular Vesicle Transfer of MiR-25-3p
Authors: Kuang Yaoyun , Zheng Xuan , Zhang Lin , Graf Irina , Bähr Mathias , Doeppner Thorsten R
Published: June 2021

Transplantation of mesenchymal stem cells (MSCs) yields neuroprotection and enhanced neurological recovery in pre-clinical stroke models, which is mediated by the secretion of extracellular vesicles (EVs). The latter are a heterogenous group of vesicles containing microvesicles, exosomes, and apoptotic bodies. The neuroprotective cargo of EVs, however, has not yet been identified. To investigate such a cargo and its underlying mechanism, we designed a series of in vitro and in vivo experiments. Primary neurons were exposed to oxygen-glucose-deprivation (OGD) and co-cultured with either adipose-derived MSCs (ADMSCs) or treated with ADMSC-secreted EVs. As expected, both ADMSCs and ADMSC-secreted EVs significantly reduced neuronal death after 12 h of OGD and 24 h of reoxygenation, showing no difference between the two treatment groups. Screening for various signaling cascades being involved in the interaction between ADMSCs and neurons revealed a decreased autophagic flux as well as a declined p53-Bnip3 activity. However, these signaling cascades were significantly blocked when ADMSCs were pretreated with the inhibitor of exosomal secretion GW4869. In light of miR-25-3p being the most highly expressed miRNA in ADMSC-EVs interacting with the p53 pathway, further in vitro work focused on this pathway. Treatment with a miR-25-3p oligonucleotide mimic reduced cell death, whereas the anti-oligonucleotide increased autophagic flux and cell death by modulating p53-Bnip3 signaling in primary neurons exposed to OGD. Likewise, native ADMSC-EVs but not EVs obtained from ADMSCs pretreated with the anti-miR-25-3p oligonucleotide (ADMSC-EVs
anti-miR-25-3p
) confirmed the aforementioned in vitro observations in C57BL6 mice exposed to cerebral ischemia. Infarct size was reduced and neurological recovery was increased in mice treated with native ADMSC-EVs when compared to ADMSC-EVs
anti-miR-25-3p
. As such, ADMSCs induce neuroprotection - at least in part - by improved autophagic flux through secreted EVs containing miR-25-3p. Hence, our work for the first time uncovers a key factor in naturally secreted ADMSC-EVs for the regulation of autophagy and induction of neuroprotection in a pre-clinical stroke model.
Abstract TP275: Brain Cell Volume Reductions After Severe Ischemic and Hemorrhagic Strokes in Rat
Authors: Kalisvaart Anna C , Wilkinson Cassandra M , Kung Tiffany F , Ma Yonglie , Winship Ian R , Colbourne Fred
Published: June 2021

Background:
Raised intracranial pressure (ICP) following severe strokes can impede blood flow to the brain, causing injury or death. There are compensatory mechanisms regulating ICP, but they are often inadequate. Interestingly, our recent observations in intracerebral hemorrhage (ICH) suggest that a volume reduction in remaining brain may serve a compensatory role after large strokes. We observed neurons well outside the hematoma reduce their volume and intercellular space 7 days after the bleed. Here, we tested the hypotheses that this volume reduction would occur sooner in both ischemic and hemorrhagic insults.

Methods:
Rats received either an ICH via stereotaxic infusion of collagenase or a sham procedure. Euthanasia and perfusion fixation occurred either 1 (N=12), 3 (N=12), or 7 (N=12) days following the ICH. Following histological processing, cellular volume, density, and cortical thickness were assessed with stereological techniques in representative brain regions such as hippocampus, striatum, and primary somatosensory cortex (S1). In a separate experiment, rats received either a middle cerebral artery occlusion (MCAO) via intraluminal suture occlusion (N=8), or a sham procedure (N=7). Rats were euthanized and perfusion fixed 1 day following the MCAO, with brains processed and assessed as described above.

Results:
After ICH, the decrease in neuronal volume (up to 60%) compared to shams had the largest effect one day following the insult in hippocampal layers CA1 and CA3 (p<0.0001), striatum (p<0.001), and S1 (p<0.05). The largest increase in cellular density occurred one day following the insult in CA1 and CA3 (p<0.0001), and striatum (p<0.001). Cortical thickness was significantly decreased on day 1 (p<0.0001). Following MCAO, cellular volume was significantly decreased compared to shams in areas CA1 (p<0.01) and S1 (p<0.05). Cellular density was significantly increased compared to shams in areas CA1 and S1 (p<0.01), and striatum (p<0.05).

Discussion:
Our data challenges the assumption that ‘healthy’ brain tissue outside the injured area maintains its volume after stroke. Given the magnitude of cell volume reductions, we posit that this is an important intracranial compliance mechanism invoked after severe strokes.
Abstract TP279: Brain-Derived Microparticles Mediate Neuroinflammation After Stroke
Authors: Chen Zhili , Chopp Michael , Zacharek Alex , Li Wei , Venkat Poornima , wang Fengjie , Landschoot-Ward Julie , Chen Jieli
Published: June 2021

Background and Purpose:
Microparticles (MPs, ~ size between 0.1-1mm) are lipid encased containers, and are involved in intercellular communication and regulate inflammation. Stroke increases brain derived MP (BDMP) secretion which induces neuroinflammation. Milk fat globule-EGF factor-8 (MFGE8) promotes apoptotic cell clearance and limits pathogenic antigen cross presentation. In this study, we investigate whether BDMP affects stroke-induced neuroinflammation; whether MFGE8 treatment reduces stroke or BDMP-induced neuroinflammation and improves functional outcome after stroke.

Method:
1) BDMPs were extracted from ischemic brain 24h after dMCAo by ultracentrifugation. 2) Adult (8 months) male C57BL/6J mice were subjected to dMCAo and were injected via tail vein 3h after stroke with: A) PBS (n=5/group); B) +BDMP(1.5х10
8
,n=6/group); C)+MFGE8 (Lactadherin, 400ug/kg, n=5/group); D) +BDMP+MFGE8 (n=6/group). A battery of neurological function outcomes and immunostaining were performed. Blood plasma was used for Western blot assay.

Result: 1)
Compared with the Stroke+PBS control group, Stroke+BDMP significantly increases inflammatory factor expression in the circulation, increases lesion volume, neurological deficits, blood brain barrier (BBB) leakage, microglial activation, and inflammatory cell infiltration (CD45, microglia/macrophage, Neutrophils) and inflammatory factor (TNFα, IL6, IL1β) expression in brain, and increases axon/white matter (WM) damage; 2) Compared to Stroke+PBS and Stroke+BDMP groups, Stroke+MFGE8 and Stroke+BDMP+MFGE8 mice exhibited significantly improved neurological outcome; decreased lesion volume and BBB leakage, reduced axon/WM damage, and decreased inflammatory cell infiltration and inflammatory factor expression in the ischemic border, respectively. MFGE8 treatment significantly increased anti-inflammatory factor (IL10) expression in ischemic brain, and decreased IL1β expression in circulation compared to Stroke+PBS and Stroke+BDMP groups, respectively.

Conclusion:
BDMP increases neuroinflammation and induces worse brain damage after stroke. MFGE8 treatment reduces stroke and BDMP-induced neurological deficits possibly via its anti-inflammatory effects.
Abstract TP281: Transcriptome Analysis of the Human Brain Microvascular Endothelial Cells During and After Oxygen-Glucose Deprivation Stress as a Tool to Identify Novel Targets
Authors: Alahmad Abraham J
Published: June 2021

Background:
The blood-brain barrier (BBB) constitutes an important component of the neurovascular unit (NVU) by providing a physical and a chemical barrier critical for the brain homeostasis. The disruption of the BBB during cerebral ischemia constitutes a key event of the disease, resulting in its opening and ultimately the formation of cerebral edema. Therefore, targeting such BBB disruption by restoring the barrier function could mitigate such insult. In this study, we investigated change in gene expression profile of the human BBB in vitro using an induced pluripotent stem cell (iPSC) based model.

Methods:
BMECs derived from two human iPSC lines (CTR90F and CTR65M) were exposed to acute OGD stress (1% O2, no glucose) for 6h, followed by reoxygenation (21% O2, 1g/L glucose) for 18h and compared to control (21% O2, 1g/L glucose, 24h) Total RNA was extracted for cDNA microarray analysis to the University of Texas Southwestern Genomic Core Facility using a ClariomD® chip. Fold-change >2 was considered statistically significant (P<0.05).

Results:
OGD/reoxygenation resulted in almost 3700 genes differentially expressed, including over 600 coding genes. Most of such differential expression occurred during the OGD phase. Reoxygenation yielded to quasi-similar expression profile than controls. Several original pathways have been identified and include nuclear receptors, PI3K/Akt signaling pathways, microRNAs, and adhesion signaling pathways.

Conclusions:
Our preliminary findings suggest that our iPSC-derived model of the BBB based on BMECs showed an overlap of several genes commonly identified as hypoxic/ischemic responsive genes, but also highlighted novel signaling pathways that have little or no literature on their function at the BBB. We are currently refining our list of genes and focusing our attention on genes that have shown the highest enrichment or depletion.
Abstract TP288: Hypoxic Human Umbilical-Derived Mesenchymal Stem Cell (hUC-MSC) Secretome in a Murine Experimental Subarachnoid Hemorrhage (SAH) Model
Authors: Wong George K , Zheng Vera ZY
Published: June 2021

Background:
Recent evidence indicates the critical role of neuroinflammation in the pathogenesis of SAH. Mesenchymal stem cells represent a new frontier in the treatment of numerous diseases and have been shown to have therapeutic effects in neurological disease model such as ischemic stroke.

Methods:
We employed a murine model of endovascular filament perforation for experimental SAH and tail vein injections were performed for hypoxic hUC-MSC secretome treatment and phosphate buffer treatment (control). The data were expressed as mean+/-SEM and statistical analyses were performed with IBM SPSS 23.0 software.

Results:
Microglia exhibited suppressed M1 polarization in hypoxic-hUC-MSC-secretome-treated mice at day 3 as compared to phosphate-buffer-treated mice. mRNA expressions of M1-polarization markers (CD16: 0.59+/-0.07; CD32: 0.62+/-0.11, p=0.024; CD68: 0.72+/-0.07. p=0.049) were downregulated and M2-polarization marker TREM2 expression were upregulated (1.57+/-0.13, p=0.013). Confocal microscopy at day 1 showed decreased CD16/32 expression in hypoxic-hUC-MSC-secretome-treated mice as compared to phosphate-buffer-treated mice, and CD206 positive cells were observed in hypoxic-hUC-MSC-secretome-treated mice. mRNA expression of IL-4 was upregulated in hypoxic-hUC-MSC-secretome-treated mice at day 1 as compared to phosphate-buffer-treated mice.

Conclusions:
Hypoxic hUC-MSC treatment had a positive effect in the modulation of neuroinflammation in a murine experimental SAH model and should be further investigated.
Abstract TP290: Differences in Alteplase Treatment by Urban, Suburban and Rural Regions Across a Large Western State
Authors: McCausland Meghan , Jansen Jim
Published: June 2021

Introduction:
Stroke patients in rural areas face multiple barriers to receiving stroke treatment, in comparison to their urban/suburban counterparts. There are many factors that may contribute to differences in treatment. Establishing whether or not regional differences in care exist is the first step in improving the stroke care system. The objective of this study was to first examine alteplase treatment in a large western state to determine if there are differences in treatment across rural and urban/suburban regions and what demographic factors contribute to those differences.

Methods:
This study analyzed 30,245 ischemic stroke patients admitted to 124 hospitals in rural and urban/suburban regions. Using 2015 - 2018 hospital discharge data, this study examined regional differences in alteplase treatment. The Rural Urban Commuting Areas (RUCA) system was used to determine rural status based off of the patient’s residence. Hospital discharge data identified ischemic stroke hospitalizations and whether or not patients received alteplase. US Census data were used to identify additional demographic factors, including income and education, at a geographic level.

Key Results:
Among those discharged with a diagnosis of ischemic stroke, results showed a 3% disparity in alteplase treatment between urban/suburban (10%) and rural residents (7%). Rural residents received treatments less often than those in urban/suburban locations. Those living in an urban/suburban region were 1.4 times more likely to receive alteplase than those living in a rural region (RR: 1.4, 95% CI: 1.3-1.6).

Conclusion:
This study identified differences in alteplase treatment across regions. Key results indicated that rural residents may face additional challenges in stroke treatment that require special consideration in stroke systems of care quality improvement efforts. Multiple factors such as distance from care, perceptions of the importance of ambulance and aid services, and availability of advanced stroke care can all play a crucial role in patients receiving adequate care quickly. Additional research is needed in the area of access to and perceptions of stroke care in rural areas to determine the best possible solutions to these challenges.
Abstract TP292: Effect of Improved Management Strategies on Study Retention Rates
Authors: Dela Cruz Michael , Aitken Kinga , Wong Ka-Ho , Rock Theodore , Majersik Jennifer J
Published: June 2021

Introduction:
Average national dropout rates of participants enrolled in a research trial are reported to be 30%. Factors contributing to loss of stroke patient retention include the lack of understanding of study expectations, lack of relationship building between patient and clinical research team, and inefficient management processes. There has been little research into interventions to improve retention. Focusing on these 3 factors may increase the likelihood of stroke patients adhering to and completing participation in stroke trials. The University of Utah Stroke Center became a StrokeNet regional coordinating center in October 2013. As study trials increased, we recognized the need to implement new trial management strategies and did so in January 2016.

Methods:
Stroke trial metrics were compared between the pre-implementation period (7/1/2012 - 12/31/2015) and a post-implementation period (1/7/2016 - 7/1/2019). The size of clinical research team personnel remained the same across the two periods: 4 coordinators and 9 physicians. Standardization of enrollment processes in stroke trials occurred during the post-implementation period. Three key aspects addressed in the post-implementation period were building rapport, setting realistic expectations, and properly educating patient and family members. The clinical research team incorporated these factors when approaching patients regardless of type of stroke trial (acute, subacute, or observational).

Results:
During the pre-implementation period, the Stroke Center research team managed 8 stroke studies with 52 patients consented with average trial duration of 23 months (SD); in the post-implementation period, there were 15 studies with 99 patients consented, with average trial duration of 22 months (SD). Retention improved after the intervention from a mean (SD) retention rate of 79.5 (29.7) %. to 90.8 (17.2) %. Although this difference was not significant, it represented meaningful change to the research staff and helped us achieve StrokeNet retention goals.

Conclusion:
Implementation of effective management strategies leads to higher retention rates of stroke patients despite no change in the size of the clinical research team.
Abstract TP295: Stroke Prevention Surgery > Quality of Life and Cognitive Ability to Drive Are Maintained After Surgical Repair of Unruptured Intracranial Aneurysm
Authors: ODonnell Joan M , Manuguerra Maurizio , Hodge Jemma L , Savage Greg , Morgan Michael K
Published: June 2021

Background:
Studies have questioned the effectiveness of surgery for the management of unruptured intracranial aneurysm (uIA). Few studies have examined the ability to drive and quality of life (QOL) after surgery for uIA.

Objective:
This study examined the effectiveness of surgical management of uIA by measuring patients’ perceived quality of life and their cognitive abilities related to driving.

Methods:
Between January 2011 and January 2016 patients with a uIA were assessed using the Quality Metric Short Form 36 (SF36) and the off-road driver screening instrument DriveSafeDriveAware. Reassessments were conducted at the 6-week post-operative follow-up for surgical patients and at 12-month follow-up for surgical and conservatively managed patients.

Results:
175 patients enrolled in the study, of which 112(66%) had surgical management of their aneurysm. For the surgical cases who completed all assessments (N=74), there was a trend for the DriveSafe pre-operative mean score of 108 (SD 10.7) to be lower than the 6-week and 12-month post-operative mean scores (111 SD 9.7 and 112 SD 10.2 respectively)(p=0.05). There were no significant changes in DriveAware scores at any epoch or between patient groups nor in the MCS in the surgical group.. There was a significant decline in PCS scores at 6 weeks post-operatively which recovered at 12 months (52 SD 8.1, 46 SD 6.8 and 52 SD 7.1 respectively)(
p
<0.01). There was no significant difference in 12-month mRS scores between the surgical cases who completed with cases who did not complete all assessments.

Conclusion:
Surgery for uIA did not affect cognitive abilities for driving at 6 weeks or 12 months after surgery. There was a decline in the QOL in the first months after surgery, however QOL returned to pre-surgical status 12 months after surgery. If the risk of seizures is low and there are no post-operative complications, returning to driving can be recommended.
Abstract TP304: Mimicking Acute Stroke Findings With a Digital Avatar
Authors: Pourebadi Maryam , LaBuzetta Jamie N , Gonzalez Cynthia , Suresh Preetham , Riek Laurel
Published: June 2021

Introduction:
It is now well-accepted that simulation-based learning (SBL) is an important component of medical education. At our institution, we have a state-of-the-art simulation center, and SBL is already incorporated into many medical subspecialties. However, commercially available patient simulators have static faces and lack the realistic depiction of non-verbal facial cues important for rapid diagnosis of neurological emergencies such as stroke. This multidisciplinary project addresses the urgent need for expressive patient simulators by developing acute stroke avatars for use in simulated healthcare training.

Methods:
Using a previously published and validated method, we developed techniques to display stroke pathologies on a virtual patient simulator (VPS). After obtaining patient or surrogate consent, we obtained source videos from patients admitted to an academic medical center who had experienced acute ischemic stroke resulting in neurological findings such as facial droop, eyelid apraxia, dysarthria, and coma. We then extracted facial features using shape-based modeling techniques, leaving anonymous feature points. Next, we applied a novel algorithm to use these feature points to build accurate computational models (masks) representing the facial characteristics of stroke. We then overlaid these prebuilt masks onto a live facial video stream to generate asymmetric expressions on a virtual avatar. This project was IRB approved.

Results:
More than 21 videos of stroke patients were made. Once the feature points were extracted from these videos, we were able to develop VPSs capable of expressing realistic asymmetric facial expressions. These avatars were then validated amongst neurologists with clinical experience in diagnosing acute ischemic stroke.

Conclusions:
This multidisciplinary effort using patient-inspired facial expressions resulted in a tool that aids the stroke education community by making virtual and robotic simulators of acute stroke more varied, interactive, and realistic.
Abstract TP305: Effect of Door to Needle Times on Clinical Outcomes in a Community Cohort
Authors: Nguyen-Huynh Mai N , Alexander Janet , Lee Catherine , Meighan Melissa , Flint Alexander , Klingman Jeffrey
Published: June 2021

Background:
Published data suggest that the faster acute stroke patients are treated with IV alteplase the better they do post discharge. It is not clear that reducing door-to-needle (DTN) time by 15 minutes (from 60 to 45 to 30) is associated with better functional outcome and/or less mortality. In a real-world practice setting, we assessed the effect of different DTN times on clinical outcomes.

Methods:
In 2016, a new standardized telestroke program for 21 stroke centers in an integrated healthcare system was launched. It included immediate evaluation by a stroke neurologist via video, expedited IV alteplase treatment, rapid CT angiographic study, and expedited transfer and treatment for patients with large vessel occlusion. From 2/15/18 to 2/25/19, we collected 90-day modified Rankin Score (mRS) for adult members who received IV alteplase. We also collected data on demographics, NIHSS, DTN times, thrombectomy, length of stay, discharge outcomes, 90-day mRS and mortality in those treated with IV alteplase stratified by the DTN time (60 vs. 45 vs. 30 minutes). Multivariate logistic regression was used to examine whether DTN category was predictive of good functional outcome (mRS=0-2) adjusted for age, gender, race, and NIHSS.

Results:
During the study period, the full cohort had 784 patients treated with IV alteplase. Average age was 71.5 ± 14.9 years with 51.8% female. Median NIHSS was 6. Median DTN time was 34 minutes. Those with faster DTN arrived more by EMS, had higher NIHSS, higher rate of thrombectomy, and shorter length of stay. A smaller cohort of 340 patients had a 90-day mRS. Multivariate models revealed a trend for faster DTN time being associated with less 90-day mortality (OR=0.81, p=0.24) and good functional outcome (OR=1.73, p=0.07) among EMS arrival (Table).

Conclusions:
In our study cohort, every 15-minute reduction in DTN had stronger association with better outcomes. Further efforts are underway to capture more complete mRS data for the full cohort.
Abstract TP31: Atrial Cardiopathy: Incidence in Endovascular Thrombectomy Patients
Authors: Arvanitakis Katerina D , Wenderoth Jason , Cheung Andrew , Alsahli Khalid , Zagami Alessandro , Berger Adam , Manning Nathan
Published: June 2021

Background:
Emerging evidence suggests that underlying atrial cardiopathy (AC) may result in thromboembolism formation in the absence of atrial fibrillation (AF). This may explain a proportion of large vessel occlusion (LVO) cryptogenic strokes. The prevalence of AC in endovascular thrombectomy (EVT) patients has not been assessed.

Methods:
A prospectively maintained database of EVT patients treated at a comprehensive stroke centres between January 2016 and September 2018 was retrospectively screened. Patients undergoing EVT for acute ischemic stroke with admission electrocardiogram (ECG) were selected. Subjects were screened for AF, paroxysmal AF (pAF) and AC with previously validated ECG markers (P-wave terminal force in lead V1 - PTFV1 >4000μV/ms & prolonged P-wave duration - PWD >120 ms.

Results:
A total of 189 patients were included. Atrial fibrillation was present in 73 (38.6%) patients. Paroxysmal AF was recorded in 31 (16.4%) patients. Atrial cardiopathy markers were present in 88 (46.6%) of the total cohort, compared to 7.7% in a published general population reference (p < 0.001). Atrial cardiopathy was present in 23 (74%) of pAF patients.

Conclusion:
Atrial cardiopathy occurs frequently in EVT patients, suggesting it may be a LVO stroke risk factor. Atrial cardiopathy may be associated with pAF. Further studies in this patient population are recommended.
Abstract TP310: Effect of an Extended Treatment Window on Transfer Times in Patients With Stroke
Authors: Beland Dawn K , Staff Ilene , Beckwith Jenna , Nouh Amre
Published: June 2021

STK-OP-1 examines transfer times for patients going to a higher level of care. Known as door in, door out or DIDO, certified stroke centers are required to report times for both ischemic and hemorrhagic stroke patients transferred to a Primary or Comprehensive Stroke Center (CSC).

Purpose:
Barriers to time-sensitive transfer and complex decision making are common. As a result, Hartford Healthcare (HHC) began a QI initiative to measure DIDO times while introducing advanced CTP imaging and treatment in the extended window, April 2018. This project evaluates the impact on DIDO.

Methods:
This multi-center QI project evaluated data pre and post implementation for stroke transfers to the CSC. Pre-implementation was May 2017 to April 2018, post-implementation May 2018 to March 2019. Patient and process of care data abstracted from Epic was entered into Excel. The main analysis compared median DIDO times using Wilcoxon Ranked Sum.

Results:
Data were collected on hospital, stroke type/severity and treatments administered; patient demographics, and key timing variables of door in/door out, EMS and CT. While there is no universal criterion for DIDO, 60 minutes is often the ultimate goal with 90 or 120 minutes as intermediate goals. Pre and post implementation median DIDO times for all hospitals were 117 and 139 minutes (p = 0.02), for HHC hospitals 115 and 137 minutes (p = 0.027) and for non-HHC hospitals 118 and 140.5 minutes (p = 0.423). Of the pre-implementation group, 7.8% had CTP imaging prior to transfer compared with 9.3% post. Extended times post-implementation include factors such as complex decision making, patient eligibility or hospital capacity issues. A new transfer algorithm was implemented April 2019. Future analyses will correlate DIDO with patient, stroke and treatment categories to better define delays and barriers.

Relevance:
A JC directive to CSCs are to develop supportive relationships with referring hospitals to facilitate efficient care. As decision making becomes more complex, the process for transfer needs to improve. DIDO goals need to be realistic to prevent secondary imaging at the CSC, i.e. the tradeoff for an extra 15 or 20 minutes should translate into shorter door to puncture times. Reducing the time to treatment may help improve patient outcomes.
Abstract TP315: Initial Stroke Severity and Reperfusion Treatment in Latin-America. Findings From the Lase Registry
Authors: Flores Alan , Barboza Miguel , Serrano Fabiola , Lavados Pablo , Fernando Gongora , Amaya Pablo , Pujol Virginia , Ameriso Sebastián , Lopez-Ruiz Minerva , Bayona Hernan , Ecos Rosa Lizbeth , Mernes Ricardo , Roa Luis , Ochoa Marco , Ruiz Angelica , Fernandez Hubert , Castillo Alejandro , Zapata Carlos , Morelos Eugenia , Reyes Abraham , León Carolina , Arauz Antonio
Published: June 2021

Information about clinical outcome and reperfusion treatment in Latin-America is not widely known. Our aim was to determine this association and other clinical factors according to the initial clinical severity in functional outcome in the population from the Latin-America Stroke Registry (LASE).

Methods:
Data were collected prospectively from consecutive patients admitted from January 2012-January 2017 in 20 Latin-American centers. The initial clinical severity was stratified according to the baseline NIHSS; 0-3 minor, 4-7 mild, 8-14 moderate, and ≥15 severe. Clinical outcome was defined by mRS at 3 months, dichotomized in good (0-2) and poor (3-6) groups for univariate and logistic multivariate analysis.

Results:
Among 5381 patients, 823(15.3%) patients received any reperfusion treatment. Of these, 84.7% received I.V. fibrinolytic, 13.2% bridging therapy, and 0.9 % primary endovascular treatment. In overall, according to initial clinical deficit by NIHSS, reperfusion treatment was associated with good outcome in mild (82.8% Vs 66.1% p=0.005), moderate (55.9 % vs. 41.6% p=0.002) and severe deficits (29.4 Vs. 18.8% p=0.002). In patients with a baseline NIHSS ≥4, multivariate analysis showed that lower NIHSS (p<0.001 OR: 1,194 CI95%: 1,169-1,219), reperfusion treatment (p<0.001 OR: 2.132 CI95%: 1.625-2.797) and urban setting (p<0.001 OR: 2.310 CI95%: 1,702-3,134) were predictors for good outcome. In reperfusion treatment patients group, multivariate analysis showed that the presence of prior ischemic cardiopathy (p=0.009 RO: 4,304 CI95%: 1,430-12,953) and lower baseline NIHSS (p< 0.001 OR: 1,232 CI95%: 1,173- 1,293) were independent variables associated with a good outcome.

Conclusion:
In this study, the rate of reperfusion treatment in 20 stroke Latin-American centers is lower than that reported from other world regions. A significant association between reperfusion treatment and good clinical outcome was observed in mild up to severe baseline deficit in our study. The effect of ischemic cardiopathy in clinical outcome in reperfusion treated patients deserves further studies. Its association with recanalization, remote pre-conditioning ischemia and collateral circulation could be explored in our population.
Abstract TP317: Utility and Cost of Inpatient Thrombophilia Testing in Ischemic Stroke Patients Aged 18-60
Authors: Apostolidou Effrosyni , Khatri Priya , Thomas Eric , Savitz Sean , Zha Alicia
Published: June 2021

Introduction:
Patients (pts) <60 years with ischemic stroke (IS) are commonly tested for thrombophilias (TP) due to the perception that there could be underlying hypercoagulable states. However, inherited TPs are largely not a risk factor for IS; and testing for acquired TPs in an acute inpatient setting may yield erroneous results that increase health care costs. We reviewed the frequency and cost of TP testing at our institution as part of a plan-do-study act cycle for improving the utilization of inpatient TP testing in young pts after IS.

Methods:
We performed a retrospective review of 18-60 year old pts admitted for IS to our comprehensive stroke center between 11/2016 and 7/2018. Pts discharged with a stroke etiology not attributed to large vessel (LV), small vessel (SV), or cardioembolic (CE) origin and the initial hospital TP testing monitored. Pts seen subsequently in clinic or later admissions in our system were monitored.

Results:
Of 1,162 pts, 104 without diagnosed LV/SV/CE etiologies were identified. At least one TP test was performed in 82 (79%) pts (Table 1). In 70 pts testing was done in the initial 24 hrs of hospitalization. One test abnormality was seen in 42 (51%) pts but anticoagulation was initiated in only one 1 patient at discharge. Forty-seven (45%) pts were followed in our outpatient clinic, with a mean follow up of 5 (0.2 – 24) months. TP was confirmed in 3 pts in clinic – two with heterozygous FVL mutation and one with known homozygous FVL mutation. The total charges of the initial inpatient testing is estimated to be as high as $222,150 for 82 patients.

Conclusion:
Frequent inpatient TP testing in young pts with cryptogenic stroke does not change management and can be costly to the hospital. Based on these results, we created a practice guideline to improve utilization of TP testing starting January 2019. A one year analysis of the effectiveness, safety, and cost for these changes is ongoing.
Abstract TP318: The Hospital Level Variation in Interhospital Transfer in Ischemic Stroke
Authors: Kolikonda Murali K , Tang Anne S , Schold Jesse D , Uchino Ken , Man Shumei
Published: June 2021

Background:
Interhospital transfer of patients with stroke to higher level of care is a resource intensive practice. This study aimed to understand the patterns of interhospital transfer in the context of hospital characteristics.

Methods:
This study included Medicare fee-for-service beneficiaries aged ≥65 years who were hospitalized in 2012 for ischemic stroke and underwent interhospital transfers. The data obtained from the American Hospital Association Annual Survey were linked to the 2012 Medicare inpatient and outpatient files. This study included patients admitted to the hospitals which were categorized as “general hospitals” with emergency departments. Hospitals were classified into receiving (high transfer in rate), sending (high transfer out rate), low flow (low transfer in or out rates), and high flow (both high transfer in and out) hospitals. Pearson’s chi-square tests were used for categorical variables and Wilcoxon Rank-Sum tests for continuous variables.

Results:
Interhospital transfers for ischemic stroke occurred in 2876 out of 4198 hospitals (68.5%), and 5.7% of ischemic stroke admissions (19,283 of 338,306 admissions). Using national average of 5.7% as cut off, the four hospital groups : 411 receiving hospitals (14.3%), 559 sending hospitals (19.4%), 1863 low-flow hospitals (64.8%). Receiving hospitals were larger than low-flow and sending hospitals by the number of beds (Median 371, 189, and 88, respectively, p<0.001) and by annual stroke volume (median 205, 86, and 26, respectively, p<0.001). The majority of receiving (75%) and low-flow hospitals (54%) were in the Metropolitan area, while sending hospital were more evenly distributed in both urban and rural area. Higher proportion of teaching hospitals were in receiving hospitals(28%) compared to low-flow(6%) and sending hospitals (1%) with p<0.001. Higher proportion of receiving (75%) and low-flow (47%) hospitals were certified stroke centers, compared to sending hospitals (16%) with p<0.001.

Conclusions:
The national patterns of interhospital transfer for ischemic stroke varies depending on the hospital size, geographical location, academic status, and stroke certification. Further study of the associated outcomes will aid in health care resource utilization.
Abstract TP325: Race-Ethnic Disparities in Utilization of Craniotomy for Spontaneous Intracerebral Hemorrhage
Authors: Garcia Roxanna , Weiss Hannah , Golnari Pedram , Nazari Pouya , Prabhakaram Shyam , Naidech Andrew , Jahromi Babak
Published: June 2021

Introduction:
Disparities in the clinical management and utilization of life-prolonging procedures among racial/ethnic minorities suffering from acute stroke has been well described for patients with spontaneous, non-traumatic intracerebral hemorrhage (ICH). However, recommendations for acute surgical management of spontaneous ICH have changed after several landmark randomized control trials were published beginning in 2005. No studies have documented differences in utilization patterns of cranial procedures by racial/ethnic minority status.

Hypothesis:
Disparities in utilization patterns of open cranial surgery exist among racial/ethnic minorities suffering from non-traumatic ICH.

Methods:
Hospitalizations from the National Inpatient Sample (NIS) between 2007 to 2015 were identified. Generalized linear multivariable models with clustering at hospital level and a logistic link function evaluated the association between race/ethnicity and likelihood of undergoing open cranial surgery. Data from a single institutional center prospective cohort was also reviewed to identify confounders not otherwise assessable.

Results:
Among 140,574 hospitalizations for ICH, a total of 16,037 (11.4%) open cranial surgeries were performed. Compared to whites, Hispanics had increased adjusted odds (1.11, 95% CI: 1.03-1.20, p=0.01) and blacks had lower adjusted odds (OR 0.92, 95% CI: 0.87- 0.98, p=0.01) of undergoing cranial surgery. When stratified by age and Elixhauser Comorbidity Index, this held true for blacks younger than 65 years and Hispanics older than 80 years (OR interaction = 0.86 and 1.38, respectively; p<0.01 for each). In the prospective cohort, blacks less than 65 years old underwent fewer craniotomies than whites (7% vs 15%, p=0.04) but these findings were confounded by hematoma location, with a higher percentage of supratentorial deep hemorrhages in blacks as compared to whites (66% vs 51%, p=0.001).

Conclusion:
Analysis of the NIS reveals disparities in utilization of cranial surgery for ICH in young blacks and older Hispanics with increasing medical comorbidities. Disparities could be partially attributable to disease specific confounders, which may not be accessible in large administrative databases.
Abstract TP330: Proportion of Intracerebral Haemorrhage Due to Cerebral Amyloid Angiopathy in the East and West
Authors: Yakushiji Yusuke , Tanaka Jun , Wilson Duncan , Charidimou Andreas , Noguchi Tomoyuki , Kawashima Masatou , Nishihara Masashi , Best Jonathan , Ide Toshihiro , Nagaishi Yukiko , Mizoguchi Megumi , Hara Hideo , Werring David J
Published: June 2021

Objectives:
We investigated whether the proportion of intracerebral haemorrhage (ICH) due to cerebral amyloid angiopathy (CAA) differs between patients of Eastern and Western origin.

Methods:
This is a retrospective international cross-sectional study of consecutive first-ever spontaneous ICH patients (including patients with surgical intervention) admitted to one stroke centre in the United Kingdom (Western centre origin) and one in Japan (Eastern centre origin) during the same period. We classified spontaneous ICH into “CAA-related ICH” defined by the Edinburgh CT diagnostic criteria, and “other ICH”. We used multivariable logistic regression analyses to assess the relationship between CAA-ICH and geographical location (Western or Eastern centre origin) or ethnicity (Western [reference], East Asian, or other) with adjustment for confounders.

Results:
Of 334 patients (median age, 71 years; male, 54%; Western centre origin, 58%), 15% were classified as CAA-ICH, and 85% were defined as other ICH. In multivariable logistic regression analysis, Eastern centre and ethnicity had a lower proportion of CAA-ICH (odds ratio [OR] vs Western centre origin 0.47, 95%CI 0.23-0.98; OR [vs. white] 0.41, 95%CI 0.20-0.97, respectively).The estimated incidence of CAA-related ICH in East Asian was similar to that in White populations, but the rate of other ICH was 2.5-fold higher in East Asian populations. Sensitivity analyses using the modified Boston criteria for diagnosis of CAA-related ICH showed similar results.

Conclusions:
The proportion CAA-ICH is lower in an Eastern compared to a Western population; this appears to be explained by a higher incidence of ICH due to hypertensive (deep perforator) arteriopathy in East Asian populations.
Abstract TP333: The Volume of an Acute Intracerebral Hemorrhage May Be Larger Than it Appears on Computed Tomography Scan
Authors: Sato Takahiro
Published: June 2021

Background and Purpose:
Computed tomography (CT) scan is difficult to detect early-onset acute intracerebral hemorrhage (ICH) rich in fresh blood correctly. We identified the presence of a perihematomal low-density lesion on CT imaging, which showed a high-intensity signal on T2-weighted imaging and an iso-intensity signal on fluid-attenuated inversion recovery imaging in magnetic resonance imaging (MRI) (Figure. A~C). It located inside of the hypo-intensity rim at the edge of hematoma on gradient recalled echo T2*-weighted imaging (Figure. D). We named it the “CT wall sign” and investigated the association with imaging findings in acute ICH.

Methods:
Patients with acute ICH within 24 hours from onset who underwent non-contrast head CT and MRI scan at the same time periods were included. The ICH volumes on CT and MRI (cm
3
) were measured using a three-dimensional slicer and compared. Subjects were divided according to the presence or absence of the CT wall sign and compared the neuroradiological variables. Statistical analyses were performed to evaluate the association between the CT wall sign and other imaging findings.

Results:
A total of 146 patients were included and the CT wall sign was observed in 42 (29%) patients. The difference in the ICH volume between MRI and CT were significantly larger in the CT wall sign-positive group than in -negative group (6.0 cm
3
versus 0.40 cm
3
,
P
<0.001). The presence of CT wall sign was significantly associated with putamen hemorrhage (
P
=0.049), large hematoma > 11.36 cm
3
(
P
=0.005), and niveau formation in the hematoma (
P
<0.001).

Conclusions:
The presence of the CT wall sign suggests that the volume of an acute ICH may be larger than it appears on CT imaging.

Key words:
Acute intracerebral hemorrhage, Computed tomography, Magnetic resonance imaging, Perihematomal low-density area.
Abstract TP334: Clinical Impact of Hematoma Expansion in LVAD Patients
Authors: Melmed Kara , Roh David , Willey Josh
Published: June 2021

Background:
Intracerebral hemorrhage (ICH) in left ventricular assist device (LVAD) patients is a devastating complication. Hematoma expansion (HE) is associated with poor outcomes in ICH patients, but the impact of HE on LVAD patients is not known. Prevention of HE includes rapid and complete coagulopathy reversal, adding further potential complications in LVAD patients given the inherent risk of hardware thrombosis. We aimed to define the occurrence of HE in the LVAD population and to determine the association between HE and mortality in this population.

Methods:
We performed a retrospective cohort study of ICH patients with preceding LVAD implantation admitted to Columbia University Irving Medical Center between Jan 2008 and April 2019. Intentionally matched ICH controls without LVADs were identified to compare rate of HE in LVAD and non LVAD patients. ICH volume was measured using ABC/2 method.We defined HE as an increase in hematoma volume of 6 ml or 33% comparing the first and last scan in 24 hours. Demographic data was compared using Pearson’s χ2 test for categorical variables and students T test and Wilcoxon rank sum test for normal and non-parametric continuous variables. The association between HE and hospital mortality in LVAD patients was examined using regression modeling after adjusting for Glasgow coma scale, age, hematoma size and location and admission INR.

Results:
Of605 LVAD patients, we identified 40 patients with ICH. Of these, 28 patients met the inclusion criteria. Mean (SD) age of LVAD patients was 56 (10), 29% of patients were female and the majority (81%) of LVAD patients were supported by Heartmate II. The median (interquartile range [IQR]) baseline hematoma size was 20.1 ml (8.6-46.9), median (IQR) ICH score was 1 (1-2). HE occurred in 16 (57%) patients supported by LVAD, and in 50% of patients without LVAD with no difference (p=0.6).There was an association between HE and in-hospital mortality in LVAD patients after adjusting for admission ICH score and INR (OR of 20.5, 95% CI: 1.8-232.8).

Conclusions:
HE is a potentially modifiable risk factor for mortality. We demonstrate that LVAD patients experience HE at a similar rate to matched controls. We show that prevention of HE with anticoagulation reversal does not increase mortality.