bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract W P276: Developing Excellence in Stroke Care Through Knowledge Building and Interprofessional Collaborative Processes
Authors: Fortin Joanne , Skrabka Krystyna , Avinoam Gail , Willems Jacqueline , Sharp Shelley , Linkewich Elizabeth
Published: July 2021

Background:
As part of a system-wide collaborative change process, a comprehensive education needs assessment was conducted with 15 acute and rehabilitation stroke teams within the Toronto Stroke Networks (TSNs). Evidence-informed educational and knowledge translation (KT) approaches were planned to bridge identified gaps for successful implementation of stroke best practices and excellence in patient care.

Purpose:
The purpose of this collaborative KT process is to enable successful learning and sustained adoption of best practices for improved patient care.

Methods:
The Education and KT plan was launched in collaboration with local organization stroke champions to integrate feedback and stimulate engagement.

Health care providers (HCPs) were oriented to the newly launched online platform, the TSNs Virtual Community of Practice (VCoP), for access to resources, ongoing knowledge exchange, and cross-system collaboration from both clinical and interprofessional perspectives.

Co-creation of stroke core foundational posters facilitated team and individual competencies for select best practices and provided HCPs with an enhanced networking opportunity building virtual competence for online collaboration.

Completed best practice posters and introduction of a small group learning guide and peer mentorship initiative will be launched to facilitate a team approach and enable practice change. A scheduled interprofessional event will reinforce online networking.

Results:
Formative evaluation of the online format has led to improved utility of the VCoP. Member checking with stroke champions has resulted in an adapted communication process with regular prompting to enable progress. Development of a strategic approach for increasing front line nurse participation was also highlighted. Further evaluation will be available at time of publishing.

Conclusions:
This innovative approach to enhance patient care has shown promise as an effective collaborative process. Iterative member checking with opportunity to adapt locally is key for successful system wide change.
Abstract W P28: Precision of Tmax and CBF Lesion Volume Estimates in CT Perfusion Imaging
Authors: Christensen Soren , Mishra Nishant , Straka Matus , Fleischmann Dominik , Bammer Roland , Zaharchuck Greg , Parsons Mark , Levi Chris , Albers Greg , Landsberg Maarten
Published: July 2021

Objective:
CT perfusion (CTP) imaging is increasingly used to select patients for acute stroke trials. Patient selection criteria are typically based on the volumes of reversibly and irreversibly injured tissue. Modern software allows for automated and quantitative assessment of these lesion volumes. There is a push towards reducing the radiation dose used in CTP protocols which may adversely affect the reproducibility of lesion volume assessments. The aim of this study was to assess the effect of radiation dose dependent image noise on the precision of lesion volume estimates.

Methods:
We generated 6 synthetic noise-less datasets based on a brain atlas of gray matter, white matter and CSF and integrated co-registered perfusion lesions from 6 acute stroke patients. For each pixel, concentration time curves were simulated using standard tracer kinetic models to obtain CTP source data based on the lesions of the 6 patients. To simulate a CTP protocol with standard radiation dose, we added CT textured noise (“Standard noise”) with a SD of 10 Hounsfield Units (HU) to the dynamic datasets and to simulate a low-dose (“high noise”) CTP protocol we added noise with a SD of 14 HU. This step was repeated 50 times per noise level and for each iteration we determined, using automated perfusion software, the volumes of the ischemic core (rCBF based) and of critically hypoperfused tissue (Tmax>6s).

Results:
With standard noise, mean CBF volume was 5.6 ml (SD 2.1) and mean Tmax>6s volume was 38.2 ml (SD 1.3). In the high noise condition, the Tmax>6s lesion volume was on average 13% (5 ml) larger (p<0.0001) than in the standard noise condition. The SD of the Tmax volumes increased from 1.3 mL to 1.8 mL with higher noise. Conversely, with high noise there was an average 5 mL (range 0-16 mL) absolute reduction in CBF lesion volume as compared to the low noise condition (p<0.0001). The CBF lesion became in many cases undetectable (estimated as 0 ml) in the high noise setting.

Conclusions:
Noise in CTP data influences the precision of lesion volume estimates. The estimate of the infarcted core seems particularly sensitive to noise. This knowledge should be used to develop guidelines that specify the maximum amount of noise (ie minimum amount of radiation) that is acceptable in a given CTP protocol.
Abstract W P310: National Trends in Carotid Artery Stenting and Endarterectomy by Sex, Race, and Region: 2007-2011
Authors: Lichtman Judith H , Leifheit-Limson Erica C , Wang Yun , Howard Virginia J , Brott Thomas G , Goldstein Larry B
Published: July 2021

Background:
CREST, a randomized trial comparing carotid artery stenting (CAS) with endarterectomy (CEA) in symptomatic and asymptomatic patients, reported in 2010 that the two procedures were similar for the composite endpoint of stroke, myocardial infarction, or death. Data on temporal trends in the use of these procedures in the US are limited, particularly by sex, race, and geographic region. We reviewed trends in utilization of CAS and CEA for ischemic stroke patients.

Methods:
Ischemic stroke hospitalizations (ICD-9 433, 434, 436) were identified for patients aged ≥18 years from the Nationwide Inpatient Sample 2007-2011 (N=480,375). Annual trends of CAS and CEA were estimated using mixed models that adjusted for patient age and comorbidities. Models were stratified by sex, race (white, black, other), and 9 geographic regions.

Results:
Overall, the proportion of stroke patients who received CAS remained relatively stable over time (2.7% in 2007 to 2.8% in 2011) while the proportion who received CEA decreased (from 21.0% to 16.3%). CAS rates increased in the three Central Regions (East North, East South, and West South) but decreased in New England; CEA declines were similar across regions. In adjusted analyses, CAS rates increased slightly for white men, decreased for men and women of other race, but remained stable for the remaining groups (Figure); CEA rates decreased for all sex-race groups. These patterns by sex and race subgroups were generally consistent across geographic regions.

Conclusions:
The proportion of hospitalized stroke patients receiving CEA decreased over time while CAS rates remained relatively stable, with slight increases seen in the Central regions of the US. There are sex-race differences in the proportion of patients who receive these procedures, but these patterns are largely similar across regions.
Abstract W P313: Effects of Organized Stroke Care on In-Hospital Mortality and Morbidity of Patients With Ischemic and Hemorrhagic Stroke: J-ASPECT Study
Authors: Nishimura Kunihiro , Kamitani Satoru , Nakai Michikazu , Kada Akiko , Nakamura Fumiaki , Kataoka Hiroharu , Miyamoto Yoshihiro , Ogasawara Kuniaki , Ono Junichi , Miyachi Shigeru , Shiokawa Yoshiaki , Matsuda Shinya Matsuda, , Nagata Izumi , Aruga Toru , Akifumi Suzuki , Toyoda Kazunori , Ishikawa Koichi , Nakagawara Jyoji , Iihara Koji
Published: July 2021

Background and Purpose:
The effectiveness of organized stroke care on stroke mortality and morbidity remains uncertain.

We examined whether organized stroke care index (OCI), which graded 0-3 based on the presence of rehabilitation, stroke team assessment, and admission to a stroke unit developed by Saposnik (Neurology 2010) influence in-hospital mortality and morbidity of patients with ischemic and hemorrhagic stroke in a nationwide study.

Methods:
Of the 1369 certified training institutions in Japan, 749 hospitals responded to a questionnaire survey regarding comprehensive stroke care capacities. Among the institutions that responded, data on patients hospitalized between April 1, 2010 and March 31, 2011, because of stroke were obtained from the Japanese Diagnosis Procedure Combination database. In-hospital mortality morbidity was analyzed using hierarchical logistic regression analysis adjusted for age, sex, level of consciousness on admission, and the number of OCI fulfilled in each component and in total.It was supported by Grants-in-Aid from the Ministry of Health, Labour and Welfare of Japan

Results:
Data from 265 institutions and 53,170 emergency-hospitalized patients were analyzed. Patients fulfilled the criteria for admission to a SCU, stroke team assessment and the presence of rehabilitation were 28.9%, 42.1% and 95.1%, respectively. Mortality adjusted for age, sex, and level of consciousness was significantly correlated with admission to a SCU (OR=0.87, p=0.039), SCU team assessment (OR=0.88,p=0.029), and OCI ( OR=0.93, p=0.031). Modified ranking scale 0 to 2 rate were also associated with significantly SCU admission (p=0.003) .These association holds for ischemic stroke and subarachnoid hemorrhage.

Conclusion:
A strong association between organized stroke care and lower mortality was apparent. These data suggest that organized stroke care should be provided to stroke patients regardless of stroke subtype.
Abstract W P320: Falls with Injury After Stroke are Associated With Incontinence and Depression
Authors: Mani Ashutosh , Dunning Kari , Alwell Kathleen , Moomaw Charles J , Kleindorfer Dawn O , Woo Daniel , Flaherty Matthew , Khatri Pooja , Adeoye Opeolu , Ferioli Simona , Kissela Brett M
Published: July 2021

Background:
Approximately 22% to 73% of persons with stroke fall yearly. Falls can result in injury, activity limitation, decreased independence and death. Several studies have investigated falls during and after inpatient rehabilitation. A community based cohort with longitudinal follow up is needed to provide prospective insight into the risk factors for falls in the general stroke population.

Purpose:
To determine rate and predictors of fall with injury 3 and 12 months post stroke

Methods:
During 2005, 460 ischemic stroke patients from the Greater Cincinnati/Northern Kentucky region were prospectively enrolled from all regional hospitals. Baseline data were collected in the acute hospital, and 3- and 12-month follow-up data were collected by subject or proxy interviews. Primary outcome was fall with injury categorized dichotomously (yes, no), analyzed separately at 3 and 12 months. Predictor variables collected at baseline included age, gender, race, and National Institutes of Health Stroke Scale (NIHSS). Predictor variables collected at 3 and 12 months included urinary incontinence (yes, no) and Center for Epidemiologic Studies Depression (CES-D) scale (score ranging from 0-30). Variables with p<.10 were entered into the model. Final model maintained all variables with p<.05, adjusting for NIHSS.

Results:
Of the 460 patients in the cohort, 27 had died by 3 months post, and another 62 had died by 12 months. Of the surviving patients, 37 of 346 (10.7%) who completed the 3-month follow-up and 33 of 247 (13.4%) who completed the 12-month follow-up reported a fall with injury. Table 1 shows demographics and results by outcome.

Conclusions:
At least 10% of patients with fairly mild stroke (average NIHSS 5) reported a fall with injury during the first year post stroke. Adjusting for NIHSS, urinary incontinence and depression were associated with a fall with injury.
Abstract W P327: Defect-Free Stroke Care Results in Lower Hospitalization Costs
Authors: Call Kevin D , Dong Li , Nelson Nancy C , Probst Daniel R
Published: July 2021

Background:
Defect-free hospital care suggests greater quality and may provide better outcomes for acute ischemic stroke(AIS) patients. Previously we reported a 5-item stroke care bundle that was associated with an increased likelihood of favorable discharge status (home/acute rehabilitation). The effect of defect-free care on total cost of hospitalization remains unknown.

Hypothesis:
Defect-free compliance to a 5-item stroke care bundle will result in significant cost savings while improving clinical outcomes.

Methods:
A retrospective cohort study of hospitalized AIS patients 18 years or older was conducted at 6 Intermountain Healthcare facilities from 2009-2012. Defect-free care was defined as compliance with 5 care measures: ED arrival to head CT <25 minutes, DTN <60 minutes, discharge on an anti-platelet, anticoagulation for patients with atrial fibrillation, and statin medication at discharge. All patients who met eligibility criteria for any measure were included. Generalized Linear Mixed (GLIMMIX) Model with random intercepts controlling for Charlson Comorbidity Index Score (CCIS) and age assessed the association of “Defect-Free” care with the following outcomes: favorable discharge status, inflation rate adjusted total cost, and 30-day readmission rate.

Results:
A total of 3,568 patients were analyzed. Patients receiving defect free care had higher rate of favorable discharge status (77.7% vs. 68.7%, p<0.0001) (Table1), and lower adjusted total costs ($10,354 vs. $11,530, p=0.0312), but showed no difference in their 30 day readmission rates (10.1% vs. 10.6%, p=0.7244), compared to patients not receiving defect-free care. After controlling for CCIS and age in a GLIMMIX model, patients receiving defect-free care were more likely to have a favorable discharge status (OR=1.295, 95% CI: 1.038, 1.615) and saved $659 on adjusted cost per case resulting in an estimated $1.9 million in savings on hospitalization costs over the study period.
Abstract W P33: Functional MRI and CBF Responses to Transient Oxygen Challenges in Acute Ischemic Stroke Patients
Authors: Wu Ona , Villien Marjorie , Thankachan Tijy , Mocking Steven , Copen William A , Schaefer Pamela W , Singhal Aneesh B
Published: July 2021

Background:
There is increasing interest in using oxygen challenges during MRI to image metabolic dysfunction in acute ischemic stroke.

Methods:
Subjects enrolled in a prospective MRI study of patients imaged within 48 h of stroke onset underwent arterial spin labeling (ASL) MRI for 10-12 min, while receiving a transient normobaric oxygen (NBO) challenge, according to this protocol: (1) Room air (RA) for 2-5 min; (2) NBO at 10-12 L/min via nonrebreather mask for 4 min; (3) RA for 2-4 min. ASL data were motion corrected and used to calculate CBF. Changes of blood-oxygen level dependent (BOLD) and perfusion MRI signal intensities during NBO were calculated (along with Z-scores) using FEAT. Mean changes within the DWI lesion (Core), ipsilateral normal tissue (IPS) and contralesional hemisphere (CNL) were compared.

Results:
Patient characteristics (N=19) were age 62±13 years, median admission NIHSS 12 [IQR 3-12], time-to-MRI 33±13 h, median Core volume 31.2 [IQR 14.3-68] cc. 6 patients were imaged after tPA therapy. One subject’s CBF data were unusable due to artifacts. Both hyperemia (N=8) and hypoperfusion (N=12) were observed in areas in and around the DWI lesion. Baseline CBF in Core was significantly higher than in CNL (P=0.01) and IPS (P=0.03), indicative of hyperemia. No significant difference was found for perfusion change in response to NBO (mean Z-score < 1.1 for all regions). In contrast, strong positive and negative BOLD responses were found both ipsilaterally and contralaterally. Negative BOLD responses were significantly smaller (P<0.01) in the Core (Z-score 1.3±1.6) than in either IPS (2.5±1.6) or CNL (2.5±1.4). Positive BOLD responses did not significantly differ across regions, but had high Z-scores (Core: 5.2±2.6, IPS: 5.8±2.7, CNL:5.8±2.9), indicating strong response to NBO.

Discussion:
Our results confirm previous reports in both human and experimental stroke models of strong increases in BOLD signal in response to NBO challenges. In addition, we found negative BOLD responses both ipsilesionally and contralesionally, often in conjunction with hyperemia, perhaps suggesting a steal effect. Future research may further elucidate the complexities of oxygen metabolism in stroke, perhaps encouraging the development of novel therapies.
Abstract W P334: VA Healthcare System Responses to National Stroke Care Reorganization
Authors: Damush Teresa M , Miller Kristine K , Plue Laurie , Schmid Arlene A , Myers Laura , Graham Glenn , Williams Linda S
Published: July 2021

Aims:
In 2011, the VA released the Acute Ischemic Stroke (AIS) Directive which mandated reorganization of acute stroke care, including self-designation as Primary (P), Limited Hours (LH), or Supporting (S) stroke center. We conducted interviews across stroke centers to understand barriers and facilitators faced in response.

Methods:
The final sample included 38 (84% invited) facilities: 9 P, 24 LH, and 5 S facilities. In total, 107 persons were interviewed including ED Chiefs, Chiefs of Neurology, ED Nurse Managers/Nurses and other staff. Semi-structured interviews were based on the AIS Directive. Completed interviews were transcribed and analyzed using Nvivo 10.

Results:
Barriers reported were a lack of personnel assigned to coordinate the facility response to the directive. Data collection and lack of staff were likewise commonly reported as barriers. For thrombolysis measures, the low number of eligible Veterans was another major barrier. LH and S facilities reported some unique barriers: access to radiology and neurology services; EMS diverting stroke patients to nearby stroke centers, maintaining staff competency, and a lack of stroke clinical champions. Some solutions applied included cross training X-ray technicians to provide head CT coverage, developing stroke order sets and templates, and staff training. Larger facilities added a stroke code pager system and improved upon its use, and established ED nurses to become first alerts for an acute stroke patient. LH and S facilities also responded by attempting to secure additional services and by establishing formal transfer agreements to improve Veteran tPA access.

Conclusions:
The AIS Directive brought focused attention to reorganizing and improving stroke care across a range of facility types. Larger VA facilities tended to follow established practices for organizing stroke care, but the unique LH designation presented challenges to consistently organize systems. Since Veterans have financial interest in presenting to a VA facility, ongoing work to organize VA care and to improve access to thrombolysis at smaller VA facilities is needed.

This protocol was supported by Genentech Inc. Protocol ML 28238, VA HSRD QUERI Rapid Response Project 11-374, and the VA Stroke QUERI Center.
Abstract W P336: Predictors of Outcome in Young Adults with Ischemic Stroke
Authors: Ali Syed F , Schwamm Lee H , Singhal Aneesh B
Published: July 2021

Introduction:
Approximately 10% - 22.5% of ischemic strokes are young adult strokes (YAS) (age 18-49 yr). We examined factors associated with home discharge and in-hospital mortality in YAS patients.

Methods:
Using our institutional GWTG database, we analyzed 5,120 consecutive stroke inpatients (01/04 - 03/13). Univariate and multivariable models explored factors associated with in-hospital mortality and home discharge.

Results:
YAS comprised 12% of the cohort (n=619). Compared to older adults, YAS patients were more often Hispanic and non-Caucasian. They presented with significantly fewer vascular risk factors and had a lower median NIHSS. Both groups received similar rates of stroke thrombolysis (IV or IA) and had similar adherence to early antithrombotics, dysphagia screening prior to oral intake, and DVT prophylaxis. YAS patients had lower in-hospital mortality (5% vs. 13%; p<0.001) and were more often discharged home (55% vs. 36%; p<0.001). Factors associated with in-hospital mortality in YAS patients were hypertension, CAD, higher NIHSS and in-hospital pneumonia. In multivariable models, only stroke severity at presentation predicted mortality (Table 1). YAS patients with increasing age, diabetes mellitus, higher NIHSS and in-hospital pneumonia were significantly less likely to be discharged home, while those receiving IV tPA were more likely to be sent home (Table 2).

Conclusion:
Our data shows that despite differences in baseline profiles, YAS patients have similar factors predicting in-hospital mortality as that reported for all acute ischemic stroke patients. IV tPA use was associated with the favorable outcome of discharge home in our YAS cohort.
Abstract W P337: Going to War for Stroke: The Experience of Establishing a Comprehensive Stroke Center in the United States
Authors: Alexandrov Anne W , Swatzell Victoria , Cudlip Fern , Alexandrov Andrei V , Martin-Schild Sheryl
Published: July 2021

Background:
Leading cultural change and performance improvement within a Stroke Center is often associated with resistance to increased workload and resources. We sought to understand neurologists’ experiences with transition to high performing U.S. Comprehensive Stroke Centers (CSC).

Methods:
Qualitative interviews were used to develop a survey for physicians currently or formerly working in CSC leadership positions identified thru listserv, fellowship directors, and web. The survey was 29 items with 6 items tied to DSM-IV PTSD experiential criteria and 3 qualitative items. Quantitative data were entered and analyzed in SPSS; qualitative data were analyzed to determine themes.

Results:
48 CSC directors responded: 60% fellowship trained vascular neurologists (VN); 65% certified VN; 8% neurocritical care certified; 6% interventionalists. Sites were 67% academic; this was the first leadership position for 54%, with 9.3+6.5 (median 8) years as program leader. Prior to assuming leadership, tPA rates averaged 2.8%+4.8%, median 1.2%, with 40% not giving tPA; leader tPA rates averaged 12.1%+8.7%, median 9.5% (mean diff 9.1; 95% CI 6.9-11.3; p<0.001). Perceptions were dichotomized by agreement (Table); 21% met 1 PTSD criterion, while 12.5% met 6 criteria. Neurologists were identified as most supportive (44%), but also most commonly (27%) seen as least supportive. Strong intent to leave was 20%, while 33% were intent on staying. Insufficient pay (33%) and lack of hospital/physician administrative support (33%) were the most common reasons for dissatisfaction. Qualitative themes included need for “Authentic Support” from hospital/physician administrators’ and “Vigilante’ Caring” tied to persistence/work ethic.

Conclusions:
Despite challenges, CSC leaders are highly motivated, although rates of experiences tied to PTSD approaches that of soldiers. Hospital/physician administrators must improve support of stroke warriors to ensure optimal performance.
Abstract W P342: Point-of-Purchase Stroke Educational Campaign at Supermarket is Effective for Rural Residents
Authors: Inoue Yasuteru , Honda Shoji , Watanabe Masaki , Ando Yukio
Published: July 2021

Background and purpose:
Like in western countries, the number of elderly people is markedly increasing in Japan. This trend is especially pronounced in rural areas. Although there were studies about stroke enlightenments for younger individuals, educational campaign for elderly people is also needed. The aim of the present study is to verify the effectiveness of stroke educational campaign for the rural residents in Japan.

Methods:
We produced a flyer instructing stroke sign and symptoms, and encouraging immediate calling for emergent medical service (EMS) on identification of stroke signs and symptoms. In December 2012, we conducted a 3-week stroke educational campaign at supermarkets in rural town in Japan. The population of the campaign area was 16981 (male 8129 and female 8852) and percentage of people aged 65 and higher was 39.8%. A total of 5000 sheets of flyers were distributed at the point of purchase to the customers. Questionnaires on stroke knowledge and appropriate action on identification of stroke, consisted of multiple-choice and closed type questions, were filled out before and 3 months after the campaign.

Results:
A total of 882 residents were responded to the questionnaire before and 3 months after the educational campaign; 409 vs.473, respectively. Of these, 686 respondents (78%) were aged over 65 years. At 3 month after the educational campaign, proportions of correct answer for hemiplegia, numbness of one side were higher as compared with those before the campaign; 58% vs. 49%, 57% vs. 50%, respectively (p<0.05) . The proportion of calling EMS on identifying stroke signs and symptoms was higher than that before the campaign; 54% vs. 40% (p<0.001). Among the questionnaire respondents
aged
65 years or older, proportions of correct answer for numbness of one side; 53% vs. 44% (p<0.05) and calling for EMS on identifying stroke signs and symptoms; 51 vs. 36% (p<0.001) were higher than those before the educational campaign.

Conclusions:
These data suggest that a simple point-of-purchase stroke educational campaign using educational flyers could have a meaningful impact on the stroke enlightenments for elderly people in rural area.
Abstract W P364: Relationships Between Endothelial Function, Biological Markers and Cerebral Small Vessel Diseasein Patients with Chronic Cerebrovascular Disease and Comorbidity
Authors: Nezu Tomohisa , Hosomi Naohisa , Aoki Shiro , Takahashi Tetsuya , Sugimoto Takamichi , Maruyama Hirofumi , Higashi Yukihito , Hayashi Tomonori , Matsumoto Masayasu
Published: July 2021

Background and Purpose:
Pathogenesis of white matter lesions is thought to be associated with endothelial dysfunction and inflammation. Ultrasound assessment of brachial artery flow mediated dilation (FMD) as a noninvasive and useful method has been recently used as an index of endothelium-dependent vasodilation. The aim of this study was to investigate the associations between endothelial function which was evaluated by FMD and the severity of white matter lesions in patients with chronic cerebrovascular disease and comorbidity. Additionally, we evaluated association between FMD and the number of circulating progenitor cells.

Methods:
Patients with cerebrovascular diseases history and other untypical neurological problems were enrolled in this study (n=63; 39 male, 69.8±10.0 years). Patients were classified according to periventricular hyperintensities (PVH) and deep white matter hyperintensities (DWMH) scores by fluid-attenuate inversion recovery image of magnetic resonance images (Fazekas gradings). Endothelial dysfunction was defined as a FMD≤4.5%. The numbers of CD34+/CD133+ cells defined as circulating progenitor cells were evaluated by flow cytometry.

Results:
The patients with endothelial dysfunction (n=39, 61.9%) were older (72.4±7.6 vs. 65.5±11.8, P=0.007), more frequently male (74.4% vs. 41.7%, P=0.016) and more frequently had hypertension (89.7% vs. 37.5%, P<0.001) than the patients without. FMD was negatively correlated with age, the severity of PVH and the severity of DWMH (R
2
=0.120, p=0.006, R
2
=0.280, p<0.001 and R
2
=0.234, p<0.001, respectively). In addition, FMD was positively correlated with the number of circulating progenitor cell (R
2
=0.078, p=0.034). After multivariate analysis with age, sex, presence of stroke and comorbidities, endothelial dysfunction was independently associated with the severity of PVH (standardized partial regression coefficient [β] 0.703, p=0.002), as well as DWMH (β 0.589, p=0.042).

Conclusion:
Endothelial dysfunction which was evaluated by FMD might be predictive for the grade of cerebral small vessel disease.
Abstract W P374: Coated-Platelet Levels Correlate With HAS-BLED Scores in Stroke Patients With Atrial Fibrillation
Authors: Prodan Calin , Vincent Andrea , Kirkpatrick Angelia , Dale George
Published: July 2021

Background:
Coated-platelets are a subset of procoagulant platelets observed upon dual agonist stimulation with collagen and thrombin. Coated-platelet levels are increased in non-lacunar ischemic stroke compared to controls; however, patients with early hemorrhagic transformation have lower coated-platelet levels than those without. In contrast to brain infarction, coated-platelet levels are decreased in intracerebral hemorrhage and inversely correlated with the size of the bleed. Because anticoagulation is a key preventive treatment in cardioembolic stroke, we investigated the existence of a relationship between coated-platelets and bleeding risk in stroke patients with atrial fibrillation.

Methods:
Coated-platelet levels, reported as percent of platelets converted to coated-platelets, were determined in 45 consecutive patients with acute stroke and atrial fibrillation. Exclusion criteria consisted of dementia, stroke due to other causes than atrial fibrillation, > 96 hours between onset of symptoms and coated-platelet assay, current anticoagulation, prior thrombolytics or abnormal PT/PTT/INR. Bleeding risk was determined for each patient using the HAS-BLED score. The correlation between individual coated-platelet levels and HAS-BLED scores was determined using the Pearson correlation coefficient.

Results:
Coated-platelet levels for the 45 patients were 41.0 ± 13.9% (mean ± SD, range 13.2 to 69.7%), consistent with previous data in patients with non-lacunar ischemic stroke. Mean HAS-BLED score was 3.2 ± 1.6, with a range between 1 and 7. A highly significant inverse linear correlation between coated-platelet levels and HAS-BLED scores was observed (p < 0.001, r = -0.67).

Conclusions:
Lower coated-platelet levels correlate with higher HAS-BLED scores in patients with stroke due to atrial fibrillation, suggesting that decreased coated-platelet synthesis is present in patients with an increased risk for bleeding. Our results are consistent with previously published research showing lower coated-platelet levels in intracerebral hemorrhage and early hemorrhagic transformation of ischemic stroke, and support a role played by this subset of activated platelets in the balance between thrombosis and hemorrhage.
Abstract W P43: Clot Characteristics on Ct-angiography Predict Early Recanalization With Intravenous Tpa in Patients With Acute Ischemic Stroke
Authors: Mishra Sachin , Dykeman Jonathan , Almekhlafi Mohammed , Eesa Muneer , Sohn Sung Il , Bal Simerpreet , Goyal Mayank , Demchuk Andrew , Menon Bijoy
Published: July 2021

Objective:
We explore relationships amongst known and novel clot characteristics identified on CTA and early recanalization with IV tPA using classification and regression tree analysis (CART).

Methods:
Data is from patients presenting with acute ischemic stroke and proximal anterior circulation occlusions from the Calgary CTA database (2003-2012) and the Keimyung Stroke Registry (2005-2009). Patients who received IV t-PA followed by endovascular therapy were included. Clot location, clot length, residual flow through clot, ratio of contrast HU pre/post clot (cirHU) and distance of clot from M1 origin (for M1 MCA occlusions), were assessed on baseline CT-angio using OsiriX (Fig 1). Early recanalization (TICI 2a, 2b & 3) with IV t-PA was assessed on DSA first run.

Results:
We identified 228 patients (50.4% male, median age 69 yrs, median baseline NIHSS 17) who fulfilled inclusion criteria. Median symptom onset to IV t-PA time was 120 mins (IQR=70 mins) and median IV t-PA bolus to first angio run time was 70.5 mins (IQR=62 mins). Patients with residual flow within clot are five times more likely to recanalize than those without. Patients with residual flow within clot and a shorter clot length (≤15mm) were the most likely to recanalize(70.6%). Patients without residual flow with a carotid T/L occlusion rarely recanalized (1.7%). Patients without residual flow in M1 clots recanalized more if they were distal and had a cirHU < 2 (36.8%). (Fig 2). Inter-rater reliability for these clot characteristics was good to excellent.

Conclusion:
Clot characteristics on CTA could help physicians estimate early recanalization rates with IV tPA for proximal clots ranging from 0% to more than 80%.
Abstract W P50: The Influence of Obesity on Outcomes After Intravenous Thrombolysis for Acute Ischemic Stroke
Authors: Chaudhry Saqib A , Hussain Syed I , Nickles Adrienne V , Reeves Mat J
Published: July 2021

Background:
Current ASA guidelines do not recommend increasing the dose of intravenous tissue plasminogen activator (IV rt-PA) for acute ischemic stroke patients weighing >100 kg. However, the consequences of such potential under-dosing may mean that it is less effective or even less harmful.

Objective:
To determine the relationship between obesity and clinical outcomes among acute ischemic stroke patients receiving IV rt-PA.

Methods:
We identified patients who received IV recombinant tissue plasminogen activator (rt-PA) at 35 hospitals participating in the Michigan Coverdell Acute Stroke Registry from January2009 to December 2011. All ischemic strokes treated within 4.5 hours with non-missing BMI data were included in the analysis. Patient BMI was dichotomized as obese (BMI ≥30) or non-obese (BMI <30). Outcome measures included symptomatic intracerebral hemorrhage (sICH), in-hospital death, complications, length of stay (LOS) and discharge to home. The independent effects of obesity on outcomes were analyzed using logistic regression analysis with adjustment for age, gender, race and medical history.

Results:
Of 698 AIS patients who received IV rt-PA 536 (76.7%) had information on BMI recorded. Among those, 263 (37.7%) were obese. Compared to non-obese patients, obese patients were more likely to be women (57.8% vs. 44.6% p=0.0007), be younger (mean age 64.0 vs. 69.7 p<0.0001), and have hypertension and diabetes mellitus. Obese patients had longer LOS (mean 7.0 vs. 5.8 days, p=0.009) and were more likely to develop urinary tract infections (6.3 % vs. 11.3 %; p=0.009). In a multivariate regression model adjusting for age, gender, race medical comorbidities, obese to non-obese patients rates of sICH (OR, 95% CI 1.2 (0.47- 3.2), p= 0.68, death [OR, 95% CI 1.2 (0.56- 2.8),p=0.60] and discharge to home [OR, 95% CI 1.0 (0.69- 1.5), p=0.89)were all similar.

Conclusion:
Obese patients receiving IV t-PA treatment for acute ischemic stroke had similar rates of in-hospital mortality, discharge to home and sICH, but they had longer LOS and rates of UTI. Future studies should be undertaken to determine if the clinical efficacy of tPA is affected by under-dosing focusing on both radiographic recanalization rates and functional clinical outcomes.
Abstract W P60: A Pooled Analysis Indicates the Promise and Pitfalls of Improving Upon Intravenous rt-PA for Ischemic Stroke
Authors: Mandava Pitchaiah , Shah Shreyansh D , Sarma Anand K , Dalmeida William , Kent Thomas A
Published: July 2021

BACKGROUND:
While intravenous thrombolysis (IVT) remains the only established therapy for ischemic stroke including beyond 3 hours, there is considerable room for improvement in IVT outcomes. Non-randomized series suggested better outcomes for add-on therapies; however randomized clinical trials (RCTs) were often equivocal. One reason for these discrepancies is that imbalances in important baseline factors between treatment and control arms affect all but the largest trials and can produce misleading results. We developed techniques to identify potentially efficacious therapies by generating a pooled outcome model. Here we tested RCTs attempting to improve upon IVT against this model at each treatment arm’s baseline NIHSS and age.

METHODS:
We generated outcome models (mortality, mRS 0-1, mRS 0-2) pooled from the thrombolytic arms of all IV tPA RCTs with the novel feature of multi-dimensional statistical intervals. A function was iteratively fitted and individual results of IV, add-on and endovascular arms tested against this model to determine whether outcomes surpassed the + p< .05 surface (see mRS0-2 Fig.).

RESULTS:
Functions derived from 19 IVT RCT thrombolytic arms representing 2748 subjects were generated (Mortality: r
2
=0.51; mRS0-1: r
2
=0.79; 0-2: r
2
=0.85). No treatment increased mortality. Three hour IVT/ultrasound with (TUCSON) or without (CLOTBUST) microspheres, the neuroprotectant Cerebrolysin and IA tPA alone (SYNTHESIS) had better functional outcomes, as did CTP-guided 6 hr. IV tenecteplase. Notably, 4.5 hour SYNTHESIS-EXPANSION (IA tPA) and IMS III (IV tPA + endovascular) did not. No extended window device showed benefit.

CONCLUSION:
We found that several treatments show the potential to improve outcome compared to our pooled IVT model, including 3 hour ultrasound, IA tPA and 6 hr. tenecteplase. Consistent with the cardiac experience, there remains little evidence that the 3 hour window can be extended other than by an IV thrombolytic.
Abstract W P61: Treatment of Ischemic Stroke With recombinant Tissue Plasminogen-Activator in Pregnancy: A Population Study
Authors: Shah Shreyansh , Murthy Santosh , Karanth Siddharth , Bershad Eric M , Venkatasubba Rao Chethan P , Suarez Jose
Published: July 2021

Background:
Stroke during pregnancy is a rare but potentially devastating event. Reported experience with thrombolysis in pregnant patients is limited. Our aim is to study outcomes of thrombolysis in stroke associated with pregnancy by using Nationwide Inpatient Sample (NIS).

Methods:
Pregnant patients with Acute Ischemic Stroke (AIS) were identified from the 2005-2010 NIS using International Classification of Diseases, Ninth Revision (ICD-9) codes. Pregnant patients who received thrombolysis were compared with those who did not receive thrombolysis based on demographics, comorbidities, hospital characteristics, and outcomes. The main outcomes were in-hospital mortality, home-discharge and intracerebral hemorrhage (ICH).

Results:
We identified 2603 pregnant patients admitted with a diagnosis of AIS, of whom 56 (2.15%) of received thrombolysis. Pregnant patients with AIS were more likely to be treated with thrombolysis at teaching hospitals compared to non-teaching hospitals (2.78% vs 1.06%, p<0.05). Pregnant patients with AIS also had more severe Elixhauser comorbidity scores (p<0.001). Thrombolysis in pregnant patients was associated with higher in-hospital moratlity rate (26.8% vs 4.6%, p<0.001) and lower home discharge rate (44.6% vs 60.1% , p<0.05) but similar rate of ICH. In the regression model on pregnant patients with AIS, the main independent predictors of in-hospital mortality were thrombolysis (OR: 5.97, CI: 3.01-11.84, p<0.001) and ICH (OR: 2.34, CI: 1.34-4.07, p<0.001).

Conclusions:
Stroke outcomes following thrombolysis appears to be less favorable in pregnant patients. Prospective confirmation of these findings is warranted.
Abstract W P65: Determinants of Favourable Response to Thrombolysis in Wake-Up Ischaemic Stroke
Authors: manawadu dulka , Bodla Shankaranand , Keep Jeff , Kalra Lalit
Published: July 2021

Background and Purpose:
Wake up Ischaemic Stroke (WUIS) patients may have the potential to benefit from thrombolysis. As the duration between stroke onset and treatment, the main determinant of response to thrombolysis, is unknown in these patients, a major consideration is to identify other clinical markers predictive of a favourable response.

Methods:
Subjects were selected by consecutive sampling of a prospective register a tertiary stroke centre between January 2009 and December 2010. The inclusion criteria were last seen normal <12 hours but >4.5 hours from symptom onset and met thrombolysis criteria apart from time. Data on baseline clinical characteristics, imaging and treatment were extracted from the register. Mortality and modified Rankin Scale (mRS) were assessed at 90 days. Symptomatic intracerebral haemorrhage (sICH) was assessed at 24 hours. Logistic regression was undertaken to identify independent determinants of these outcomes, and those significant at p<0.1 were stratified and assessed using Peto’s fixed odds ratio for thrombolysis versus no thrombolysis.

Results:
Of the 122 WUIS patients fulfilling inclusion criteria 68 were thrombolysed and 54 (44%) were not thrombolysed. There were no differences in the baseline characteristics between the two groups. Logistic regression showed an independent relationship of age and NIHSS score with 90 day mortality and mRS 0-2 (p<0.01 for all) and with stroke subtype (p<0.1). There were no independent predictors of sICH. Thrombolysis had the best outcomes in WUIS patients aged 80-89 years with cardio-embolic stroke and NIHSS scores of 10-19 (Fig 1).

Conclusions:
Older WUIS patients and those with embolic stroke appear to benefit most from thrombolysis.
Abstract W P68: Treatment of Unruptured Intracranial Aneurysms Within the Pediatric Population
Authors: Asaithambi Ganesh , Adil Malik M , Jordan Lori C , Qureshi Adnan I
Published: July 2021

Background:
The rates and outcomes of treatments for intracranial aneurysms have not been exclusively determined within the pediatric population. We determined the rates of endovascular and microsurgical treatments for unruptured intracranial aneurysms (UIA) and associated rates of favorable outcome.

Methods:
We analyzed the data obtained as part of the Kids’ Inpatient Database between 2003 and 2009 with primary diagnosis of UIA (identified by the International Classification of Disease codes, Ninth Revision). Patients undergoing endovascular treatment (ET) were compared to those undergoing microsurgical treatment (MT). Outcomes were defined as rates of intracerebral hemorrhage (ICH), subarachnoid hemorrhage (SAH), in-hospital mortality, or favorable outcome (discharge disposition of home/self-care).

Results:
There were 818 cases of UIAs during the timeline examined. A total of 111 patients (mean age 14±6 years, 37.6% female) underwent MT and another 200 patients (mean age 13±7 years, 42.5% female) underwent ET. There were no significant differences in rates of ICH (MT 4.4% versus ET 2%, p=0.4) and SAH (MT 15.5% versus ET 9.3%, p=0.2). There was no in-hospital mortality among those who received MT, and 3 patients died among those who received ET. A high rate of favorable outcome was observed in patients who received either treatment (MT 87.7% versus ET 91.6%, p=0.4). There was a trend towards a significantly shorter mean hospitalization stay among those who received ET as opposed to MT (6±12 days versus 9±11 days, p=0.06). There was also a significant trend towards higher utilization of ET as opposed to MT from 2003 to 2009 (p=0.02).

Conclusion:
Although outcomes except for length of stay are comparable between ET and MT patients, there is a trend towards higher utilization of ET among children with UIAs from 2003 to 2009.
Abstract W P73: Feasibility and Preliminary Results of Whole Blood RNA-Sequencing Analysis in Patients With Intracranial Aneurysms
Authors: Haas Blake , Gonzalez Nestor R , Nikkola Elina , Connolly Mark , Hsu William , Bui Alex , Vinuela Fernando , Pajukanta Päivi
Published: July 2021

Introduction:
Intracranial aneurysms (IA) growth and rupture have been associated with chronic remodeling of the arterial wall. However, the pathobiology of this process remains poorly understood. The objective of the present study was to evaluate the feasibility of analyzing gene expression patterns in peripheral blood of patients with ruptured and unruptured saccular IAs.

Materials and Methods:
We analyzed human whole blood transcriptomes by performing paired-end, 100 bp RNA-sequencing (RNAseq) using the Illumina platform. We used STAR to align reads to the genome, HTSeq to count reads, and DESeq to normalize counts across samples. Self-reported patient information was used to correct expression values for ancestry, age, and sex. We utilized weighted gene co-expression network analysis (WGCNA) to identify gene expression network modules associated with IA size and rupture. The DAVID tool was employed to search for Gene Ontology enrichment in relevant modules.

Results:
Samples from 12 patients (9 females, age 57.6 +/-12) with IAs were analyzed. Four had ruptured aneurysms. RNA isolation and application of the methodology described above was successful in all samples. Although the small sample size prevents us from drawing definite conclusions, we observed promising novel co-expression networks for IAs: WCGNA analysis showed down-regulation of two transcript modules associated with ruptured IA status (r=-0.78, p=0.008 and r=-0.77, p=0.009), and up-regulation of two modules associated with aneurysm size (r=0.86, p=0.002 and r=0.9, p=4e-04), respectively. DAVID analyses showed that genes upregulated in an IA size-associated module were enriched with genes involved in cellular respiration and translation, while genes involved in transcription were down-regulated in a module associated with ruptured IAs.

Conclusions:
Whole blood RNAseq analysis is a feasible tool to capture transcriptome dynamics and achieve a better understanding of the pathophysiology of IAs. Further longitudinal studies of patients with IAs using network analysis are justified.
Abstract W P8: Role of Core Infarct Volume Affecting the Number Needed to Treat in Endovascular Therapy for Acute Ischemic Stroke From Large Vessel Occlusion
Authors: Zaidat Osama O , Yoo Albert , Janardhan Vallabh , Frei Don , Ammar Lynne , Myer Denise , To Christina , Kuo Sophia S , Buell Hope , Barraza Leticia , Bose Arani , Sit Siu Po ,   for the Penumbra Trialists
Published: July 2021

Purpose:
The infarct core has been hypothesized to be highly predictive of treatment effect for endovascular intervention in acute ischemic stroke from large vessel proximal occlusion. The purpose of this study was to determine how it affects the number of patients needed to treat (NNT) by this therapy to improve long term functional status.

Methods:
Patients with acute stroke not eligible and/or refractory to IV rtPA, treated by the Penumbra System (N=463) were pooled from various studies: Pivotal (N=83), PICS (N=174), RetroSTART (N=96) and START (N=110). They were compared with 62 control patients who were eligible for but not treated by endovascular therapy. The NNT for both groups to achieve 90 day functional independence as defined by an mRS score of ≤2 were compared. The impact of the infarct core at presentation defined by ASPECTS trichotomized as small (8-10), medium (5-7) and large (0-4) was assessed. The distribution of the infarct core (N) for Penumbra:control patients were: 257:50, 155:7 and 51:3, respectively for small, medium and large. Two control patients did not have ASPECTS scores.

Results:
There were no differences in baseline characteristics between the two group median values (Control;Penumbra): Age (72;68), NIHSS (18;17), ASPECTS (ASP) (9;8). There were significant differences in rate of recanalization, all-cause mortality and good functional outcome (mRS ≤2) but not symptomatic ICH (Table). The NNT to improve functional status was 5.6 for the entire cohort of treated patients, 4.7 for those with small core, 4.1 for medium and 12.8 for large.

Conclusion:
These data indicate that endovascular treatment may not be effective in patients with a large infarct core and could contribute to the high NNT needed to achieve long term good functional status. Eliminating this group at time of triage may significantly lower the NNT and improve the treatment effect of this therapy.