bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract NS4: Dizziness In Stroke: Triage Nurses Identify Posterior Circulation Strokes In A Comprehensive Stroke Center Emergency Department Using Three Simple Questions
Authors: Thorsen Tawnae , karstens raquel c , Gupta Atul , Bernardino Tina , Gaffney Denise , Punsalang Lorina , Mkrtumyan Alvina , Sangha Navdeep S
Published: February 2022

Introduction:
Recognition of stroke alerts in triage are imperative to the rapid evaluation of acute ischemic stroke. Patients who present to the Emergency Department (ED) with a chief complaint of dizziness have historically been challenging for triage nurses. Missed triage opportunities may result in increased door to needle (DTN) times. The goal of this study was to assess if a dizziness triage tool can reduce missed posterior circulation strokes and decrease DTN times.

Methods:
We developed the following three questions: Is the room spinning, shaking, or are you lightheaded; does it come and go or is it persistent with sudden onset within the last six hours; does the dizziness change with position. If the description of dizziness was sudden, spinning/shaking, persistent, and non-positional, then the patient was triaged as a stroke. ED RNs were trained and education tools were distributed in January 2019. Data were retrospectively reviewed on patients who presented with dizziness, were diagnosed with posterior circulation strokes, and received IV Alteplase. Dizziness for this study was defined as: dizziness, dizzy, vertigo, lightheaded, room spinning, room shaking, unsteadiness, and/or imbalance. Data were reviewed pre and post implementation over a three-year period to assess the percentage of patients captured by the tool and its impact on DTN times. Data were analyzed using a t-test.

Results:
Patients with a Brain Alert were older (71 {IQR 59-74}) vs. No Brain Alert (57 {IQR 53-63} p=0.036) yrs. 86% of women had no brain alert whereas 62% of men did. The median NIHSS for Brain Alert was 3 (IQR 1-4) vs. no brain was 1 (IQR 1-4) (p=0.89). In the pre-implementation time frame 47% (7/15) of dizzy patients diagnosed with ischemic stroke and received alteplase were captured by a triage nurse activated brain alert. Post implementation 89% (8/9) and 100% (4/4) were captured in 2019 and 2020 respectively. Median DTN for dizzy patients improved from 56 mins in 2018 (IQR 44-92) to 46 mins in 2020 (IQR 36-60) p=0.025.

Conclusion:
A triage nurse three-question dizziness tool is successful and sustainable in identifying posterior circulation strokes in the emergency department which helps to decrease DTN times in these patients.
Abstract NS5: A Telestroke Nurse/Neuroradiologist Model For Extended Window Code Stroke Triage
Authors: Helms Anna Maria , Williams Laura O , Cardona Chelsea , De Filipp Gary J , Karamchandani Rahul R , Asimos Andrew W
Published: February 2022

Background and Purpose:
Two distinguishing features of our stroke network include the routine involvement of a telestroke nurse (TSRN) for code stroke activations at non-thrombectomy centers, and immediate availability of neuroradiologist for imaging interpretation. With revascularization treatment decision making for patients presenting beyond 4.5 hours from last known well (LKW) being driven by imaging, we hypothesized that reliance on those resources could substantially decrease the routine involvement of a teleneurologist.

Methods:
On May 1, 2021, we implemented a workflow for code stroke activations beyond 4.5 hours from LKW that relied on a TSRN supported by a neuroradiologist. Criteria for a code stroke activation included any cortical sign on exam or suspicion for a basilar artery occlusion, as determined by the treating Emergency Medicine (EM) physician. All qualifying patients underwent a CTA with or without CTP imaging. Patients with a target occlusion on CTA confirmed by the neuroradiologist, the neurointerventionalist and neurologist at the thrombectomy center are immediately contacted to join the triaging team. Patients without a target occlusion on CTA are managed without the involvement of a teleneurologist, unless requested by the treating EM physician.

Results:
In our first 3 months utilizing this workflow, there were 509 extended window code stroke activations. In 64% (n=326) of these cases, a teleneurologist was not initially involved, representing a cumulative 58% absolute decrease in teleneurology consultations when compared to the prior three months. For 95% (n=311) of those cases, a target LVO was not identified. For the 15 LVO cases, the median CTA acquisition to LVO confirmation time was 14 minutes (IQR 11-25.5). Ninety-five percent (n=311) of non-LVO cases were subsequently managed by the EM physician. Of those cases, 90% (n=292) were admitted to the hospital. For 47% (n=138) of admitted cases, the patient had a non-stroke diagnosis. Thirty-nine percent (n=114) of all admitted cases were managed by a hospitalist physician without a neurology consult.

Conclusions:
A telestroke nurse/neuroradiologist model for extended window code stroke triage can substantially reduce the routine involvement of a teleneurologist.
Abstract TMP100: The Effect Of Prehospital Treatment With Magnesium On Symptomatic Hemorrhagic Transformation In Cerebral Ischemia
Authors: Jang Michael , Sanossian Nerses , Shkirkova Kristina , Kim-tenser May A , Liebeskind David S , Saver Jeffrey L , Starkman Sidney , Hamilton Scott
Published: February 2022

Introduction:
Symptomatic hemorrhagic transformation (sHT) is a known complication of acute ischemic stroke and is associated with worse outcomes. Previously, low serum magnesium levels have been associated with higher rates of sHT. This study evaluated the effect of prehospital treatment with intravenous magnesium on rates of sHT.

Methods:
Subjects were participating in the NIH Field Administration of Stroke Therapy Magnesium (FAST-MAG) clinical trial. A total of 20 grams of magnesium or matching placebo was administered via 4 gram bolus in the field followed by 16 gram infusion over 24 hours. All subjects with cerebral ischemia were evaluated for the presence of symptomatic hemorrhagic transformation defined as an increase in NIHSS >=4 points in the setting of imaging showing new hemorrhage within the ischemia territory.

Results:
A total of 1245 cases of cerebral ischemia were evaluated by paramedics on average 40 (SD 85) minutes and treated with magnesium or placebo on average 63 (SD 85) minutes after last known well time. Study population was age 71 (SD 18), 45% female, 78% white, 14% black, 8% Asian, 20% Hispanic ethnicity, 36% were treated with intravenous TPA, 78% hypertensive and 23% diabetic. Median NIHSS at ED arrival was 7 [IQR2-15]. There were 187 cases of clinical deterioration of which 43 were due to hemorrhagic transformation (3.4%). Rates of sHT were not statistically different in those who received magnesium vs. placebo (17/632 [2.7%] vs 26/613 [4.2%], p=0.134). Although HT was more common in TPA cases (6% vs 2%, p<0.001), magnesium had no effect on sHT in this subgroup 5.3% vs 7.3%, p-0.399

Conclusions:
Hyper-acute high-dose intravenous magnesium did not lead to a significant decrease in rates of sHT following acute ischemic stroke. It is possible that a subgroup with low baseline magnesium levels could have benefited.
Abstract TMP102: Timing Of Withdrawal Of Antithrombotics And Impact On Stroke
Authors: Stanton Robert J , Khoury Jane C , Kleindorfer Dawn O , Alwell Kathleen S , Aziz Yasmin , Robinson David , Flaherty Matthew L , Woo Daniel , De Los Rios La Rosa Felipe , Demel Stacie L , Madsen Tracy , Star Michael , Slavin Sabreena , Coleman Elisheva R , Walsh Kyle B , Jasne Adam , Mistry Eva , Ferioli Simona , Mackey Jason , Haverbusch Mary , Adeoye Opeolu M , Broderick Joseph P , Kissela Brett M
Published: February 2022

Background:
Antithrombotic medications (AT) are often withheld before procedures to reduce risk of bleeding. In 2005, members of our team reported that 5.2% of ischemic strokes were associated with the withdrawal of AT in the preceding 60 days. Subsequently, new medications, including DOACs, have become widely used. Given changing prescription and practice patterns we sought to compare rates of stroke in the setting of antithrombotic withdrawal in 2010 and 2015.

Methods:
The GCNKSS is a population-based stroke study from the Greater Cincinnati region. In 2005, 2010, and 2015, we captured all strokes in the Greater Cincinnati/Northern Kentucky 5 county area by screening ICD9 codes 430-436 and ICD10 (2015) codes I60-I68, and G45-46. Study nurses abstracted all cases and physicians adjudicated each event. Data regarding the withdrawal of AT and timing were captured. 2005 data was included as a reference. Fisher’s exact test was used to examine differences by years.

Results:
In 2010 and 2015, 4768 cases of ischemic stroke were identified. Across the study periods, those that were on AT at time of stroke versus those who stopped AT <60 days prior to incident stroke were of similar median age, 73 and 74 years respectively, and of similar sex (55 vs 52%) and race (21 vs 18%) distribution. Atrial fibrillation (30 vs 52%) and median baseline NIHSS (3 vs 4) were higher in those who stopped AT < 60 days prior to stroke than those on AT. Of the 4768, 228 (4.8%) occurred within 60 days of withdrawal of an antithrombotic medication. The proportion of strokes in the setting of warfarin being held is the only AT that had a significant change, decreasing in 2015 (Table).

Conclusions:
The withdrawal of AT is associated with 228 (4.8%) of ischemic strokes within 60 days in our study population. These rates remain consistent across our study periods. This highlights that despite new agents, stroke in the setting of AT withdrawal remains consistent and the decision to stop AT must be carefully considered.
Abstract TMP112: Stroke-associated Pneumonia Impairs Pulmonary Host Defense While Infection Impairs Stroke Recovery
Authors: Simoes Braga Boisserand Ligia , Sharma Lokesh , Tran Tho , Chen Bridget , Kim Jooyoung , Dela Cruz Charles , Sansing Lauren H
Published: February 2022

Introduction:
Stroke-associated pneumonia (SAP) is a common clinical complication implicated in increased morbidity and mortality after stroke. Dysphagia and stroke-induced immunodepression may contribute to SAP. However, a better understanding of the processes underlying the infection-induced immune response in the recovering brain remains to be unveiled.

Methods:
Stroke was modeled in mice by tMCAO (1h) followed by reperfusion; at day 3 mice received an oropharyngeal Klebsiella inoculation. To examine how lung infection affects the brain immune response, we compared tMCAo+infection vs tMCAo+vehicle. Functional outcomes and brain leukocyte cytokine expression were analyzed. To investigate how stroke affects the host response to pulmonary infection we compared Sham+infection vs tMCAo+ infection. Bacterial burden in the lung and spleen, tissue injury and immune cell profile in the lungs were evaluated at day 2 post-infection.

Results/Conclusions:
We detected similar brain leukocyte numbers between the tMCAo infected vs vehicle groups. However, in the tMCAo infected group, cytotoxic T-cells (CD8+) produced less IL-6 and IFNγ and granulocytes/neutrophils produced less INFγ. tMCAo infected animals also exhibited a worse functional recovery (Fig 1a). Klebsiella CFUs were increased in spleen in mice with stroke compared to sham, while lung (BAL) white blood cells counts were reduced in the stroke group, with altered cellular composition (Fig 1b).Our investigation has revealed that lung infection attenuates cytokine production in the brain after stroke. That could have a dual effect, positive for brain injury but detrimental for fighting infection. Stroke affects the response to lung infection by reducing lung leukocyte counts and increasing bacterial dissemination. Advancing our understanding of the mechanisms driving altered immune responses in SAP important for identifying potential treatment targets.
Abstract TMP114: Time-based Dynamic Analyses Of Gene Expression In Monocytes, Neutrophils And Whole Blood Identify Key Hub Genes And Functional Processes Following Acute Ischemic Stroke
Authors: Carmona-Mora Paulina , Knepp Bodie , Jickling Glen , Zhan Xinhua , Hakoupian Marisa , Hull Heather , Alomar Noor , Amini Hajar , Sharp Frank R , Stamova Boryana , Ander Bradley
Published: February 2022

Gene expression changes in peripheral blood reflect injury and repair processes occurring post ischemic stroke (IS). Our study explored the dynamic time-dependent expression of key genes involved in the immune response after IS to better understand the biology and to identify specific diagnostic biomarkers. Using RNA-sequencing, we analyzed gene expression profiles of 38 IS patients and 18 controls with at least one vascular risk factor (VRFC) including diabetes and/or hypertension and/or hypercholesterolemia in isolated monocytes, neutrophils and whole blood. We used two approaches: Weighted Gene Co-expression Network Analysis (WGCNA) with respect to time after stroke onset; and differential expression analyses with subject samples split into time points (TPs) from stroke onset (TP0=VRFC; TP1=0-24 h; TP2=24-48 h; and TP3≥48 h). In WGCNA, highly interconnected “hub” genes were identified for modules significant to time (p<0.05). Differentially expressed genes (DEGs) with diagnosisхTP p<0.02 and fold-change>
Abstract TMP116: Pharmacological Inhibition Of Endoplasmic Reticulum Stress Prevents Intracranial Aneurysm Rupture
Authors: Ishiguro Taichi , Ai Jinglu , Lawton Michael , Hashimoto Tomoki
Published: February 2022

Background:
The endoplasmic reticulum (ER) is responsible for cellular protein synthesis and folding. Cellular stimuli that perturb ER homeostasis create an imbalance between the protein-folding load and capacity of ER, causing unfolded or misfolded proteins to accumulate in the ER lumen, known as ER stress. Recent studies suggested that ER stress plays significant roles in the pathogenesis of inflammatory vascular diseases. Since inflammation is emerging as a vital component of the pathophysiology of intracranial aneurysms, we hypothesized that ER stress promotes the development of aneurysm rupture by inducing sustained vascular wall inflammation. We tested this hypothesis utilizing pharmacological approaches in mice.

Methods:
We used 10-week-old male C57BL/6J mice and induced intracranial aneurysms by combining an elastase injection and hypertension. We tested the effects of an ER stress activator (Tunicamycin) and inhibitor (4-phenylbutyric acid, 4-PBA) on the development of aneurysmal rupture. In addition, we assessed the roles of ER stress induced via deactivation of epidermal growth factor receptor (EGFR) by Erlotinib on aneurysm rupture.

Results:
The pharmacological inhibition of ER stress significantly decreased the rupture rate (P<0.05, Fig. A). Meanwhile, there was a trend for the ER stress activator to increase the rupture rate (P=0.17, Fig.B). Moreover, the pharmacological inhibition of the EGFR pathway with Erlotinib significantly reduced the rupture rate (P<0.05, Fig. C). In addition, Erlotinib treatment reduced the mRNA expression of ER stress markers GRP78 and CHOP (Fig.D-E).

Conclusions:
The pharmacological inhibition of ER stress decreased aneurysmal rupture in a mouse model of intracranial aneurysm. In addition, inhibition of EGFR decreased aneurysm rupture through the reduction of ER stress. Our findings suggest that ER stress and its upstream EGFR pathway may serve as novel therapeutic targets for preventing aneurysm rupture.
Abstract TMP18: Global Estimates Of Frequency And Outcomes Of Coronavirus Disease 2019 Associated Stroke And Myocardial Infarction
Authors: Tannous Jonika , Pan Alan , Potter Thomas , Bako Abdulaziz , Meeks Jennifer , Baig Eman , Johnson Carnayla , Khan Osman , Vahidy Farhaan S
Published: February 2022

Background:
We evaluated the frequency and outcomes of Coronavirus Disease 2019 (COVID-19) associated stroke (ischemic and hemorrhagic) and myocardial infarction (MI) in a global research network.

Methods:
All adult (≥ 18 years) patients with ICD-10 diagnoses of COVID-19 were included and those with a stroke (ischemic stroke, intracerebral hemorrhage [ICH], transient ischemic attach [TIA] or subarachnoid hemorrhage [SAH]) or myocardial infarction (MI) ± 28 days from COVID-19 diagnosis were flagged. Individuals with a prior history of stroke / MI were excluded. COVID-19 associated stroke (CAS) and MI (CAM) frequencies were compared to prior AHA-reported population-based incidences. Severe COVID-19 disease (use of ventilator, intubation, or life support) and 90-day mortality were evaluated among no-stroke/MI and stroke/MI subgroups utilizing general linear models adjusted for age, sex, race/ethnicity, and Charlson Comorbidity Index scores. Adjusted odds ratios (aOR) and 95% confidence intervals (CI) are reported.

Results:
Between Jan 2020 and Jul 2021, we identified 637,820 COVID-19 patients of whom 4,559 (0.71%) had a CAS and 6,972 (1.09%) had a CAM. COVID-19 was associated with significantly higher stroke/MI rates compared to population based reported incidence (ORs, CI for CAS 1.99, 1.93 - 2.05 and CAM 3.09, 3.01 - 3.16). Severe COVID disease was observed among 1.07% of COVID-19 only patients, 11.25% of CAS patients (aOR, CI: 4.82, 4.35 - 5.34), and 14.81% of CAM patients (aOR, CI: 5.77, 5.34 - 5.22). 90-Day mortality was 1.92% for COVID-19 only patients, 14.35% for CAS patients (aOR, CI: 3.16, 2.87 - 3.46), and 20.52% for CAM patients (aOR, CI: 4.12, 3.85 - 4.41). Group specific demographic and outcome proportions are reported (Figure).

Conclusion:
The COVID-19 pandemic has tremendously exacerbated the burden of cerebrovascular and cardiovascular disease globally. Continued work is needed to understand drivers of poor outcomes among COVID-19 patients.
Abstract TMP2: A Framework For The Study Of Hemorrhagic Microangiopathy With Cerebral Cavernous Malformation As A Paradigm
Authors: Romanos Sharbel , Srinath Abhinav , Li Ying , Chen Chang , Bindal Akash , Foxley Sean , DeBiasse Dorothy , Dimov Alexey , Hobson Nick , Benchehida Habib , Carroll Timothy , Moore Thomas , Lightle Rhonda , Stadnik Agnieszka , Girard Romuald , Awad Issam A
Published: February 2022

Introduction:
Hemorrhagic microangiopathies (HMAs) are age-related cerebral microbleeds associated with an increased risk of cognitive decline and intracerebral hemorrhage (ICH). HMAs share a strikingly similar appearance on MRI to cerebral cavernous malformations (CCMs), which are clusters of leaky capillaries predisposing patients to brain bleeding. We hypothesize that HMAs and CCMs share common dysregulated genes and pathways reflecting hemorrhagic failure of the neurovascular unit. Thus, biomarkers developed in CCM may be applicable to HMA.

Methods:
Extracted mRNA from 5 HMA lesions collected at autopsy along with 3 non-lesional brain sections from the same patients was sequenced, and differentially expressed genes (DEGs) were identified. Enrichment analyses were performed using the Reactome database. Pathways related to postulated mechanisms of HMA were identified, as well as those overlapping pathways with a previously published CCM transcriptome. Dynamic Contrast-Enhanced Quantitative Perfusion (DCEQP) and Quantitative Susceptibility Mapping (QSM) MRIs were performed on 11 HMA patients, 12 age-matched, and 22 young healthy subjects assessing vascular permeability and iron content, as previously done in CCM. Mean permeability and QSM values were calculated for white and gray matter in the frontal, temporal, parietal, and occipital lobes.

Results:
Differential analyses of the HMA transcriptome identified 376 DEGs (
p
<0.05), including 46 common with the CCM transcriptome. The Reactome database identified 231 enriched pathways (
p
<0.05) in HMAs, 8 of which overlapped with CCM, primarily relating to endothelial permeability, cell junctions, and the extracellular matrix. Additional inflammatory pathways with mechanistic links to plasma compounds were identified in HMA as in CCM. We further demonstrate feasibility of background brain QSM and DCEQP acquisition in the brain of HMA patients and controls.

Conclusion:
Transcriptomic commonalities suggest that similar pipelines for plasma and imaging biomarkers developed in CCM research may be adapted for risk assessment and monitoring of HMA. These will help improve the understanding of HMA pathogenesis and assist in patient management, offering a large public health impact.
Abstract TMP26: Understanding Changes In Thrombectomy Eligibility Among Large Vessel Occlusion Stroke Transfers In A Hub-and-spoke Telestroke System
Authors: Regenhardt Robert W , Awad Amine , Kraft Andrew W , Rosenthal Joseph A , Dmytriw Adam A , Vranic Justin E , Bonkhoff Anna K , Bretzner Martin , Etherton Mark R , Hirsch Joshua A , Rabinov James D , Singhal Aneesh B , Rost Natalia S , Stapleton Christopher J , Leslie-mazwi Thabele M , Patel Aman B
Published: February 2022

Introduction:
Endovascular thrombectomy (EVT) has revolutionized the care of emergent large vessel occlusion (ELVO) stroke patients. It is, therefore, crucial to optimize its delivery to eligible candidates. Within hub-and-spoke hospital system models, some patients first present to distant spoke hospitals and require transfer to hub hospitals for EVT. We sought to understand changes in EVT eligibility during transfer.

Methods:
Consecutive EVT candidates presenting to 25 spokes from 2018 to 2020 with pre-transfer CTA-defined ELVO and Alberta Stroke Program Early CT Score ≥6 were identified from a prospectively maintained database. Outcomes of interest included hub EVT, reasons for EVT ineligibility, and 90-day functional independence (modified Rankin Scale, mRS ≤2).

Results:
Among 258 patients, the median age was 70 years (IQR 60-81) and 50% were female. Forty-four percent underwent EVT upon hub arrival, of which 87% achieved Thrombolysis in Cerebral Infarction 2b-3 reperfusion. Compared to EVT-eligible patients, ineligible patients were older (73 vs 68 years, p=0.04), had lower NIH Stroke Scale (NIHSS, 10 vs 16, p<0.0001), longer LKW-hub arrival time (8.4 vs 4.6 hours, p<0.0001), and received less IV alteplase (32% vs 45%, p=0.04). The clinical reasons cited for becoming EVT ineligible upon hub arrival included large established infarct (49%), mild symptoms (33%), recanalization (6%), distal occlusion location (5%), subocclusive lesion (3%), and goals of care (3%). Becoming EVT ineligible independently reduced the odds of 90-day functional independence (aOR=0.26, 95%CI=0.12,0.56; p=0.001), even when controlling for age, NIHSS, and LKW-hub arrival time.

Conclusions:
These data support that approaches to increase EVT eligibility among ELVO transfers may improve long term outcomes. Infarct growth represents the primary reason for ineligibility. Possible interventions include direct field triage to the hub when feasible, improving inter-hospital transfer times, supporting ischemic penumbra before EVT, and developing novel agents to slow infarct growth.
Abstract TMP31: Genesis Of Malpractice Risk With Mechanical Thrombectomy
Authors: Qureshi Kasim , Farooq Muhammad U , Gorelick Philip B
Published: February 2022

Introduction:
In 1996 tPA was approved for treatment of acute ischemic stroke (AIS), leading to a higher bar for quality of care but also to many medical-legal claims. Subsequent reviews of legal databases showed most lawsuits were for failure to treat rather than for tPA-associated complications. Acute stroke care has again undergone a paradigm shift with the landmark mechanical thrombectomy (MT) trials, the AHA’s recommendation of MT for AIS, and its adoption as standard of care therapy for acute large vessel occlusions of the brain in select patients. Accordingly, lawsuits have been brought forward alleging malpractice. The aim of our study was to systematically review legal databases to better understand claims pertaining to MT.

Methods:
Legal databases were searched using key words “stroke” and “thrombectomy”. Cases were included if they were medical malpractice claims for AIS involving endovascular MT. Cases with and without verdicts were included and were systematically categorized based on claims and case details including vascular territory, interventions, and plaintiff/defendant arguments.

Results:
Search criteria revealed 313 results of which 25 cases met inclusion criteria. Cases were most frequently excluded due to duplicate result (n=126), or not being a malpractice claim for AIS (n=65). Anterior circulation strokes were the cause of complaint in 13 cases, vertebrobasilar and related strokes in 10 cases, and other/unknown in 2 cases. In 16 cases MT was not performed, leading to an alleged failure to timely diagnose and treat AIS. In the remaining 9 cases where MT was performed, 8 cases also alleged failure of timely treatment and 1 claimed complications of MT. Other frequent allegations included failure of timely consultation, performance of vascular imaging, or transfer. Specific allegations related to delay in transfer included choice of road vs. air ambulance travel, and transfer to in-network hospital vs. nearest MT-capable center. One case involved a tele-stroke neurologist.

Conclusions:
Similar to medical-legal claims for tPA, failure to perform (or failure to timely perform) MT was a common complaint. In addition, delays in obtaining vascular imaging and logistical delays in transfer causing potential delays in MT were commonly noted.
Abstract TMP39: Impact Of Best Modeled Transport On Hospital Patient Volumes, Quantified Outcomes And Healthcare Cost Savings
Authors: Abbas Huda , Kamal Noreen , Paydarfar Daniel A , Holodinsky Jessalyn K
Published: February 2022

Introduction:
A previously published conditional probability field-based triage model predicts best transport options for ischemic stroke patients to access Endovascular Therapy. This model predicts whether Drip and Ship or Mothership transport results in a higher probability of excellent outcomes. To inform health system policy, it is critical to understand the change in annual hospital volume, the annual increase in the number of patients expected to have excellent outcomes, and the annual reduction in cost to the healthcare system resulting from changing prehospital transport strategies.

Methods:
We performed a case study using the stroke system in Alberta, Canada. The population of each 7 km by 7 km grid section in Alberta was obtained through the ArcGIS GeoEnrichment service. This was combined with the annual stroke incidence and large vessel occlusion (LVO) screening tool (ex. LAMS) sensitivity and positive predictive value to model the expected number of suspected LVO patients transported by ambulance. Using transport to the closest hospital as a baseline, the resultant annual change in hospital volume was determined. This was used to calculate the annual increase in the number of patients that will have excellent outcomes and resultant cost savings to the healthcare system from average post-stroke cost data.

Results:
The change in annual hospital volumes for Alberta is shown in the Figure. There was an increase of 6.65 patients predicted to have an excellent outcome (90-day mRS 0-1) annually, and an increase of 11.93 patients to have good outcomes (90-day mRS 0-2). This resulted in an annual cost savings of $283,463.86 to the healthcare system.

Conclusions:
Translating the benefit of an existing conditional probability model into the change in annual hospital volume, increase in the annual number of patients with excellent outcomes, and health system cost avoidance, allows one to fully realize the impact of using a modeled transport protocol to the health system.
Abstract TMP43: Concerning Rise In Young-onset Stroke Hospitalizations And Non-improving Outcomes In Patients From Low Household Income Quartile: A National Perspective A Decade Apart (2007 Vs. 2017)
Authors: Jain Akhil , Gowda Supreeth N , Cartagena-Santana Juliana , Valdez Confesora , Spasova Violeta , Galan Mirian , Buhl Leon Maria Cristina , Kumar Jaish , Singh Sandeep , Desai Rupak
Published: February 2022

Background:
Health equity and the reduced socioeconomic gap between communities are the main objectives of healthcare delivery in the US with a shifting focus towards social determinants of health. We aimed to compare stroke hospitalizations and outcomes in young patients with low median household income (LMHI) across two national cohorts a decade apart (2007 vs. 2017).

Methods:
We used National Inpatient Sample (2007 & 2017) to identify young-onset stroke hospitalizations (18-44 years, YOS) belonging to LMHI (0-25th quartile) using relevant codes. Demographics, comorbidities, adjusted risk of YOS and outcomes were compared between two cohorts.

Results:
Of 34249 LMHI YOS admissions, 13749 belonged to 2007 and 20500 to 2017 (median age 39 vs 38 years, p<0.001). The risk of YOS was 30% higher in 2017 young LMHI admissions than in 2007 when adjusted for socio-demographics and comorbidities (aOR 1.30, 95%CI:1.27-1.34, p<0.001)
(Table 1).
Gender distribution was comparable for YOS between 2007 and 2017. The 2017 YOS cohort often consisted of white (38.4 vs 33.3%), non-elective admissions (94.9 vs 91.1%) and often had cardiovascular comorbidities and concomitant smoking (42.4 vs 26.9%); whereas lower rates of alcohol (5.5% vs. 8.7%) and drug abuse (12.1 vs. 16%) than in 2007 (p<0.001). Though adjusted all-cause mortality was comparable between the two cohorts (aOR 0.91, 95%CI:0.82-1.00, p=0.054) with shortened stay (5 vs. 4 days) and fewer transfers in 2017; adjusted hospital costs were higher in 2017 (p<0.001).

Conclusion:
There was an alarming 30% higher risk of YOS admissions in patients from the LMHI quartile across 2 national cohorts a decade apart in the US without any significant improvement in mortality odds when controlled for confounders. Our analysis indicates the need for the adoption and propagation of preventive measures and vigilance to lessen CVD and YOS risk, improve health outcomes and decrease healthcare costs among young patients from LMHI quartile.
Abstract TMP51: Predictors Of Severe Disease In Posterior Reversible Encephalopathy Syndrome
Authors: Garg Aayushi
Published: February 2022

Background:
Despite its name, posterior reversible encephalopathy syndrome (PRES) is not always fully reversible and there might be residual neurologic sequelae or even mortality in a significant minority of patients. Factors predisposing to severe disease course in PRES are largely unclear. The aim of this study was to evaluate the predictors of in-hospital mortality and adverse discharge disposition in patients hospitalized due to PRES.

Methods:
Hospitalizations due to the primary diagnosis of PRES with known discharge disposition were identified from the Nationwide Readmissions Database 2016-2018. Survey statistics were used to compute national estimates. Univariate and multivariable logistic regression analyses were used to identify factors associated with the study outcomes. P-value <0.01 was considered significant.

Results:
There were 9,298 patients with PRES (mean±SD age: 56.2±17.6 years; female: 71.2%). Of these, 207 (2.2%) had in-hospital mortality and 4,002 (43.0%) had adverse discharge disposition, defined as discharge to a short-term hospital, a rehabilitation facility, home with in-home healthcare or hospice. Figure 1 shows the independent predictors of the study outcomes. Advanced age, history of cancer, concurrent sepsis, coma, ischemic stroke, and mechanical ventilation were associated with higher in-hospital mortality. Whereas advanced age, female sex, higher Charlson comorbidity index score, mechanical ventilation, and longer length of hospital stay were associated with a higher likelihood of adverse discharge disposition.

Conclusion:
Nearly half of the hospitalized patients with PRES have severe disease. This study identifies several clinical predictors of severe disease course in PRES.
Abstract TMP53: Nationwide Secular Changes In Severity And Outcome Of Ischemic And Hemorrhagic Strokes: A 20-Year Analysis From Japan Stroke Data Bank Involving 183,082 Patients
Authors: Toyoda Kazunori , Yoshimura Sohei , nakai michikazu , Koga Masatoshi , Sasahara Yusuke , Sonoda Kazutaka , Kamiyama Kenji , Yazawa Yukako , Kawada Sanami , SASAKI MASAHIRO , Terasaki Tadashi , Miwa Kaori , Koge Junpei , Ishigami Akiko , Wada Shinichi , Iwanaga Yoshitaka , Miyamoto Yoshihiro , Minematsu Kazuo , Kobayashi Shotai ,   Japan Stroke Data Bank Investigators
Published: February 2022

Introduction:
The Japan Stroke Data Bank (JSDB) is a 20-year long ongoing hospital-based multicenter prospective registry of hospitalized patients with acute stroke/TIA based on a web database from 130 stroke centers distributed evenly over Japan.

Hypothesis:
Secular changes in the severity and functional outcome of stroke patients would be clarified by long-lasting hospital-based registries.

Methods:
Patients registered in JSDB within 7 days after stroke onset from Jan 2000 through Dec 2019 were studied. The initial severity was assessed by the NIHSS for ischemic stroke (IS) and intracerebral hemorrhage (ICH) and by the WFNS grading for subarachnoid hemorrhage (SAH). Outcomes at hospital discharge was assessed by the mRS.

Results:
Of a total 183,082 stroke patients, 135,268 (women in 39.8%) developed IS, 36,014 (women in 42.7%) developed ICH, and 11,800 (women in 67.2%) developed SAH. Median ages at onset increased and the NIHSS and WFNS scores decreased after multivariable-adjustment in all three stroke types. Patients with favorable outcome, corresponding to the mRS 0-2, significantly increased after age-adjustment in all three IS subtypes, remained increasing after further adjustment by NIHSS and stroke history only in cardioembolic stroke (OR 1.014, 95% CI 1.008-1.020, per year), and no longer increased after further adjustment by reperfusion therapy in any subtypes. Both the frequencies of unfavorable outcome, corresponding to the mRS 5-6, and in-hospital death, significantly decreased in cardioembolic stroke (OR 0.974, 95% CI 0.968-0.980) and large-artery atherosclerosis (OR 0.975, 95% CI 0.967-0.982, both for unfavorable outcome) after multivariable-adjustment. In ICH and SAH, favorable outcome significantly decreased after multivariable-adjustment, except for SAH in men. Both the frequencies of unfavorable outcome and death after SAH significantly decreased, but those after ICH were not. These findings were generally common to both sexes when separately analyzed.

Conclusions:
Short-term functional outcome improved in IS patients during the past 20 years presumably partly due to development of acute reperfusion therapy. The outcome of hemorrhagic stroke patients did not clearly show the improvement during the same duration.
Abstract TMP58: Rest-Activity Patterns In Post-Stroke Delirium: A Pilot Study
Authors: Reznik Michael E , Moody Scott , Drake Jonathan , Margolis Seth , Rudolph James , Daiello Lori , Furie Karen L , Jones Richard
Published: February 2022

Background:
Delirium is an acute cognitive disturbance frequently characterized by abnormal levels of motor activity and sleep-wake cycle disruption. However, the degree to which delirium affects activity patterns in the acute period after stroke is unclear. We aimed to examine these patterns in a cohort of patients with intracerebral hemorrhage (ICH).

Methods:
We enrolled 40 patients with supratentorial ICH and hemiparesis who had daily delirium assessments performed by expert clinicians. Continuous measurements of activity were captured using bilateral wrist actigraphs for the duration of each patient’s admission. Activity data were collected in 1-minute intervals, with “rest” intervals defined as periods with zero activity recorded. We compared differences in activity based on delirium status across multiple time intervals using linear regression models adjusted for age, ICH severity, and mechanical ventilation.

Results:
There were 312 total days of actigraphy monitoring, of which 233 (75%) were rated as days with delirium; 85% of patients (34/40) experienced delirium during their hospitalization. In multivariable analyses, delirium days were associated with 66.3 (95% CI 9.4-123.2) fewer total minutes of rest, including 6.1% (95% CI 2.3-9.9%) fewer minutes of rest during daytime periods (06:00-21:59) and 9.2% (95% CI 3.3-15.0%) fewer minutes of rest during nocturnal periods (22:00-5:59). In separate analyses for individual hourly intervals, delirium days were associated with significantly higher levels of activity across multiple consecutive time intervals, including 05:00-09:00 and 17:00-03:00. In subgroup analyses, hyperactive or mixed delirium was associated with fewer total daily minutes of rest compared to hypoactive delirium, along with lower proportions of time at rest during both daytime and nocturnal periods (4.3% [95% CI 0.5-8.0%] and 6.5% [95% CI 0.9-12.1%] lower, respectively).

Conclusion:
Post-stroke delirium is associated with less rest and higher overall levels of activity, especially during nocturnal periods and in patients with hyperactive or mixed delirium.
Abstract TMP63: Predictors And Clinical Impact Of ASPECTS Evolution After Successful Reperfusion With Endovascular Therapy: Insight From The ETIS Registry
Authors: Anadani Mohammad , JANUEL ANNE CHRISTINE , Finitsis Stephanos N , Clarençon Frédéric , Richard Sébastien , Marnat Gaultier , bourcier romain , Sibon Igor , Dargazanli Cyril , Arquizan Caroline , BLANC RAPHAEL , LAPERGUE Bertrand , Consoli Arturo , Eugène François , vannier stephane , Caroff Jildaz , denier christian , BOULANGER Marion , Gauberti Maxime , Rouchaud Aymeric , Macian Francisco , Rosso Charlotte , ben Hassen wagih , TURC Guillaume , ozkul-wermester ozlem , PAPAGIANNAKI CHRYSANTHI , Albucher Jean Francois , LE BRAS Anthony , Evain Sarah , wolff valerie , Pop Raoul , Timsit Serge , Gentric Jean-Christophe , Bourdain Frédéric , Veunac Louis , de Havenon Adam H , Maier Benjamin , Gory Benjamin ,   ETIS
Published: February 2022

Background:
Alberta Stroke Program Early CT scan Score (ASPECTS) is a reliable imaging biomarker of infarct extension in patients with large vessel occlusions. ASPECTS evolution, a surrogate of infarct expansion, is an important predictor of functional and safety outcomes after endovascular therapy (EVT). In this study, we aimed to identify the predictors of ASPECTS evolution after successful reperfusion and the association between ASPECTS evolution and outcomes of EVT.

Methods:
We used data from the ongoing prospective multicenter Endovascular Treatment in Ischemic Stroke (ETIS) registry (NCT03776877). For the purpose of this study, we enrolled patients with anterior circulation LVO treated with EVT and achieved successful reperfusion (mTICI 2b-3). Additional inclusion criteria included 1) the availability of ASPECTS score on admission and at 24 hours after EVT 2) ASPECTS was assessed on the same imaging technique (i.e MRI or CT) on admission and at 24 hours. We considered 2 or more points decrease in ASPECTS as a significant ASPECTS change. Multivariable logistic regression analyses were used to identify the predictors of ASPECT evolution and to study the association between ASPECTS evolution and outcomes.

Results:
We included a total of 1161 patients, of whom 978 (84%) patients had at least 2 points decrease in ASPECTS score. Worsening ASPECTS score was associated with higher odds of poor functional outcome (90-day mRS 3-6), mortality, and symptomatic intracerebral hemorrhage. Admission ASPECTS, NIHSS, blood glucose, location of occlusion, final mTICI score, total number of attempts and procedure time emerged as predictors of ASPECTS evolution.

Conclusion:
ASPECTS evolution is a strong predictor of clinical and safety outcomes after successful reperfusion with EVT.
Abstract TMP64: Outcomes After Mechanical Thrombectomy In Patients With Left Ventricular Assist Devices
Authors: Ibeh Chinwe , Lavine Sean D , Mandigo Grace K , Sisti Jonathan A , Willey Joshua Z
Published: February 2022

Background:
Left ventricular assist devices (LVADs) are an established durable and lifesaving treatment option for patients with advanced heart failure. However, large vessel occlusions (LVOs) remain one of its most devastating embolic complications. Mechanical thrombectomy (MT) is safe and effective in the management of LVOs in the general population but LVO trials largely excluded patients on mechanical circulatory support and large-scale analyses of outcomes following these interventions in the LVAD population are lacking.

Methods:
Using the National Inpatient Sample (2012 - 2018) we identified all adult patients hospitalized with acute ischemic stroke (AIS). The presence of LVAD, the use of MT, and additional covariates were extracted. Descriptive statistics and multivariable regression models were used to compare outcomes following MT in patients with and without LVADs.

Results:
Of the 798,059 AIS hospitalizations identified, 366 occurred in patients with LVADs. LVAD patients were younger (mean age 59.6 [13.2] vs 70.1 [14.3], p <0.001), and were less often female (23.0% vs 50.9%, p <0.001). In the general stroke population 2% were treated with MT vs 6% in LVAD-associated AIS. Post-stroke mortality was higher among LVAD patients (18.4% vs 6.22, p=0.000). However, among patients receiving MT, there was no significant difference in in-hospital mortality between LVAD and non-LVAD patients (23.1% vs 12.5%, p=0.104). In crude analysis and after adjusting for potential confounders there was no difference in odds of discharge to home after treatment with MT (Figure).

Conclusion:
Our data suggests MT is not a futile treatment approach in patients with LVADs and may result in similar rates of good outcomes. Additional research is needed to evaluate the long-term benefits of endovascular therapy after stroke in patients on LVAD support.
Abstract TMP69: Poor Clinical Outcome Of Patients With Early Neurological Deterioration In Large Vessel Occlusion And Low NIHSS
Authors: Kim Hyun Woo , Kim Youngran , Tariq Muhammad Bilal , Abdelkhaleq Rania , Niktabe Arash , Salazar-Marioni Sergio , Sheth Sunil A
Published: February 2022

Introduction:
Early neurological deterioration (END) in patients with large vessel occlusion (LVO) stroke with low NIHSS treated with medical management (MM) has been well described. However, the effect of END on 90-day disability outcomes relative to patients presenting with more severe stroke, remains undetermined.

Methods:
From our multi-center prospective registry across 4 comprehensive stroke centers, we identified patients with LVO (basilar, ICA, M1/2, or P1 identified on CTA or MRA) from January 2018 to June 2020. Low NIHSS was defined as 0-5, and END as a worsening of > 3 points. To determine the effect of END on outcomes, we used propensity score to match patients who presented with low NIHSS who suffered END by age and worsened NIHSS (i.e. subsequent, greater NIHSS) to patients who presented initially with LVO and comparable NIHSS.

Results:
Among 348 patients with LVO acute ischemic stroke, median age was 67 [IQR 59-76], 46.6% were female. 58 patients (17%) of the cohort had low NIHSS. Compared to the higher NIHSS group, low NIHSS group had less EVT performed (39.7% vs 78.3%, p=<0.001), greater ASPECTS (9 vs 8, p=0.001), fewer M1 occlusions (27.6% vs 51.7%, p<0.001), and lower prevalence of risk factors, such as hypertension, hyperlipidemia, and congestive heart failure (50.0% vs 71.4, p=0.001; 20.7% vs 36.9%, p=0.018; and 0.0% vs 9.3%, p=0.016, respectively). Overall 90-day disability outcomes (mRS 0-2) were better in the low NIHSS group (58.6% vs 44.8%, p=0.055) although it did not reach statistical significance. On the other hand, 41.4% of low NIHSS group did not achieve functional independence. Of 35 patients with initial MM in the low NIHSS group, 7 (20%) suffered END. The median increase in NIHSS was 7 (range 4-15), and only 1 patient achieved 90-day mRS 0-2. In a propensity matching analysis, LVO patients with initially low NIHSS patients followed by END had significantly worse outcomes than the patients who initially presented with comparable NIHSS (Coef=26, p=<0.001).

Conclusions:
In patients with low NIHSS and LVO, those treated initially with MM who suffer END have worse clinical outcomes when matched to patients with comparable NIHSS post-worsening. These finding suggest that the delaying EVT in this population may lead to worsened outcomes.
Abstract TMP70: Comparing Machine Learning Algorithms And Regression Models For Predicting Functional Outcome In The Stratis Registry
Authors: Jumaa Mouhammad A , Zoghi Zeinab , Zaidi Syed F , Mueller-Kronast Nils , Zaidat Osama , Castonguay Alicia C
Published: February 2022

Background:
Machine learning algorithms have emerged as powerful predictive tools in the field of acute ischemic stroke. Here, we examine the predictive performance of a machine algorithm compared to logistic regression for predicting functional outcomes in the prospective Systematic Evaluation of Patients Treated With Neurothrombectomy Devices for Acute Ischemic Stroke (STRATIS) Registry.

Methods:
The STRATIS Registry was a prospective, observational study of the use of the Solitaire device in acute ischemic stroke patients. Patients with posterior circulation stroke or missing 90-day mRS were excluding from the analysis. A statistical algorithm (logistic regression) and a machine learning algorithm (decision tree) were implemented on the preprocessed dataset using 10-fold cross-validation method where 80% of the data were fed into the models to be trained and the remaining 20% were utilized in the test phase to evaluate the performance of the models for prediction of 90-day mRS score as dichotomous output (0-2=1, 3-6=0).

Results:
Of the 938 STRATIS patients, 702 with 90-day mRS were included. The machine learning model outperformed the logistic regression model with a 0.92±0.026 Area Under Curve (AUC) score compared to a 0.88±0.028 AUC score obtained by implementing logistic regression.

Conclusion:
Our machine learning model delivered improved performance in comparison with the statistical model in predicting 90-day functional outcome. More studies are needed to understand and externally validate the predictive capacity of our machine learning model.
Abstract TMP71: Optimizing Stroke Outcome Prediction: Derivation And Validation Of The Charlotte Large Artery Occlusion Endovascular Therapy Outcome Score
Authors: Karamchandani Rahul R , Prasad Tanushree , Strong Edwin , Rhoten Jeremy , Asimos Andrew W
Published: February 2022

Introduction:
Prognostic scores for large artery occlusion patients treated with endovascular intervention have not incorporated CTP parameters. We derived the Charlotte Large artery occlusion Endovascular therapy Outcome Score (CLEOS) to optimize outcome prediction after mechanical thrombectomy.

Methods:
Patients presenting with an ICA or MCA occlusion treated with thrombectomy from November 2016-July 2020 were included from our health system’s prospectively collected, code stroke registry in the derivation analysis. Prognostic factors independently associated with poor outcomes (90-day mRS score 4-6) were combined with CTP parameters in a regression model. Internal cross-validation was performed. A separate, prospective validation cohort was included from the registry with patients from December 2020-April 2021. The final scale was compared to previously reported scales using Area Under the Curve-Receiver Operator Characteristic analysis.

Results:
646 patients were included in the derivation analysis and 60 patients in the separate validation cohort. CLEOS = (6 x Age) + (13 x NIHSS) + Glucose - (162 x CBV Index). CLEOS predicted poor 90-day outcomes (AUC 0.74, 95% CI 0.71-0.78) better than the Stroke Prognostication using Age and National Institute of Health Stroke Scale-100 Index (AUC 0.63, p < 0.0001), the Houston Intra-Arterial Therapy 2 score (AUC 0.69, p = 0.0029), and the Pittsburgh Response to Endovascular therapy score (AUC 0.71, p = 0.0240) in a combined analysis of the derivation and validation cohorts. Patients with CLEOS scores ≥ 850 did not have a lower risk of poor 90-day outcomes despite excellent revascularization (modified TICI 2c-3).

Conclusions:
CLEOS can predict poor 90-day outcomes after an ICA or MCA occlusion and help identify patients unlikely to benefit from endovascular thrombectomy despite excellent revascularization.