bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract WP37: The Effect of Weekend Admission on Intracerebral Hemorrhage Outcome at High Volume Institutions
Authors: McDowell Michael , Shea Nicholas , Kellner Christopher , Sussman Eric , Meyers Emma , Bruce Sam , Bruce Rachel , Heuts Simon , Connolly E. Sander
Published: March 2022

INTRODUCTION:
Admission for urgent care on weekends has been suggested to result in increased risk of poor outcome. Studies have suggested that admissions for intracerebral hemorrhage (ICH) have resulted in a significant increase in in-hospital mortality on a national level. The utilization of regional, high volume centers specializing in the management of acute stroke may be a potential remedy to this variability in care. We sought to test this hypothesis by examining the outcomes of ICH patients admitted to the Columbia University Medical Center Neurological ICU (NICU).

Methods:
The medical records of 229 ICH patients admitted to the NICU from 2009 to 2012 were identified through the Intra-Cerebral Outcomes Project prospective database and examined for weekend versus weekday admission to the NICU, as well as day versus night admission. Multiple logistic regression was used to asses for predictors of in-patient mortality and poor outcome at 3 months, defined as a modified Rankin score of 4 or greater. Outcome measures were corrected for admission severity of presentation and demographics.

Results:
Sixty-five admissions were recorded to have occurred on the weekend, with 14 (21.5%) patients dying in hospital. Forty-nine (29.8%) of the 164 weekday admissions resulted in mortality (p=0.27). The 3 month follow up of surviving patients was 3.4 in weekend admissions and 3.1 in weekday admissions (p= 0.93). One hundred and one night admissions occurred, with 30 in-hospital mortalities. One hundred twenty-one patients were admitted during the day shift, with 32 in-patient mortalities occurring (p=0.54). The average outcome at 3 months was 3.0 in night admissions and 3.3 in day-time admissions (p=0.39).

Conclusions:
No significant difference in the mortality or 3 month outcome of patients was identified regardless of day or time of admission. This may be secondary to a higher number of weekend and night duty personnel capable of being mobilized during crisis situations compared to other centers, or the increased experience of medical staff in the work up and acute management of ICH patients. When possible, aggressive diversion of patients to high volume, specialized care centers may reduce the risk of variability in care based on time of admission.
Abstract WP371: A Transient Ischemic Attack Electronic Decision Support Tool Can Safely Reduce Management Delays
Authors: Yang Chwan-Fen , Funnell Michael , Cariga Pietro , Ranta Annemarei
Published: March 2022

INTRODUCTION:
Management of transient ischemic attacks (TIAs) via rapid access specialist TIA services reduces stroke risk. Providing sufficiently rapid specialist input is challenging in some areas and resultant management delays are often unavoidable. In 2009 an electronic decision support (EDS) tool was launched in a New Zealand provincial district to help improve general practitioner (GP) diagnostic accuracy and if deemed appropriate encourage GPs to initiate best medical therapy and diagnostic work-up at first point of contact rather than awaiting specialist review.

HYPOTHESIS:
We assessed the hypothesis that TIA EDS in the primary care setting can safely reduce delays in TIA management.

Methods:
Patient records of those referred to the hospital TIA service from January through June 2011 were reviewed comparing patients who were referred by GPs using TIA EDS with those referred not using EDS (‘control’).

RESULTS:
During the study period a total of 69 patients were referred to the outpatient TIA clinic with 41 (59%) referrals coming from GPs. Overall GPs utilized EDS in the management of 43 patients, 22 (51%) of which resulted in specialist referral. Best medical therapy was in place sooner in the EDS than the control group (2.63 ± 1.12 vs 7.77 ±1.66 days; p<0.05) and a larger proportion of the EDS group had best medical therapy in place within 24 hours (77% vs 70%; p <0.001). Outpatient diagnostic work-up including brain and carotid imaging was completed sooner in the EDS group compared with controls (19.53 ± 2.85 vs 32.33 ± 5.76 days, p=0.05). Careful screening of hospital and primary care records did not identify any adverse events relating to EDS use.

CONCLUSION:
In the setting of limited access to rapid specialist TIA services TIA EDS can safely assist GPs in initiating best medical management and diagnostic work-up in the primary care setting resulting in timelier management. However, the observational and retrospective design of this study dictate cautious interpretation and a randomized controlled trial (FASTEST Trial ACTRN12611000792921) to more conclusively assess TIA EDS efficacy, safety, and cost-effectiveness is currently ongoing.
Abstract WP380: Diastolic Dysfunction Predicts In-Hospital Death in Stroke and Transient Ischemic Attack Patients with Atrial Fibrillation
Authors: Tateishi Yohei , Tsujino Akira , Hamabe Jumpei ,   Cerebrovascular Cntr, Tasaki Osamu ,   Emergency Med Cntr, Maemura Koji ,   Dept of Cardiovascular Medicine, Nagata Izumi ,   Dept of Neurosurgery
Published: March 2022

Background:
The aim of this study is to identify whether diastolic dysfunction predicts in-hospital death in stroke and transient ischemic attack (TIA) patients with atrial fibrillation.

Method:
Consecutive ischemic stroke patients within 24 hours of onset were analyzed. Then, we enrolled stroke and TIA patients with atrial fibrillation. All patients underwent MRI or CT and blood test on admission and transthoratic echocardiography within 24 hours of admission. Diastolic filling pressure was estimated as the ratio of early transmitral flow velocity (E) to mitral annular velocity (e’) on transthoracic echocardiography. Plasma brain natriuretic peptide and D-dimer were measured on admission. We calculated initial diffusion weighted imaging (DWI) lesion volume and assessed Albert Stroke Program Early CT score of DWI (ASPECTS-DWI). Stroke severity was assessed by the National Institute of Health Stroke Scale (NIHSS) score. Patients were divided into two groups: the deceased group and the survival group. Univariate and multivariate analysis were conducted to identify predictors of in-hospital death.

Results:
Four-hundred sixty three patients with ischemic stroke were analyzed. Of these, 204 patients were categorized into stroke subtype of cardioembolic infarction with atrial fibrillation. Thirty-two patients (16%) could not undergo MRI due to pacemaker implantation. The median length of stay in hospital was 19 days (interquartile range 15 - 27). Twenty five patients (12%) deceased during hospitalization. Patients with the deceased group had higher NIHSS score (median, 20 versus 8, p<0.001), D-dimer level (median, 2.8 versus 1.7 mg/dl, p=0.019), DWI lesion volume (median, 197 versus 7 ml, p<0.001), ASPECTS-DWI (median, 3 versus 9, p<0.001), and E/e’ (median, 25.2 versus 13.6, p<0.001) than patients with the survival group. In multivariate analysis, higher E/e’ was an independent predictor of in-hospital death (OR 0.711, 95% CI 0.52 to 0.98, p=0.036). The cutoff value of E/e’ for prediction in-hospital death was 20 with the sensitivity of 100% and specificity of 88%.

Conclusion:
Diastolic dysfunction may be associated with in-hospital death in stroke and TIA patients with atrial fibrillation.
Abstract WP388: The Impact of Chronic Kidney Disease on the Outcome of Large Artery Atherosclerotic Stroke: Results from Taiwan Stroke Registry
Authors: Yeh Shin-Joe , Tang Sung-Chun , Tsai Li-Kai , Jeng Jiann-Shing ,   Taiwan Stroke Registry Investigators
Published: March 2022

Background and Purpose:
Chronic kidney disease (CKD) has been shown a risk factor for the development of large artery atherosclerosis (LAA) and stroke. However, its impact on the outcome of acute stroke patients with LAA has not been well investigated.

Methods:
Patients who were prospectively registered in Taiwan Stroke Registry (TSR) and had LAA subtype of acute ischemic stroke were included. The severity of CKD was evaluated by estimated glomerular filtration rate (eGFR) as normal (>90 mL/min/1.73 m
2
), mild (60-89 mL/min/1.73 m
2
), moderate (30-59 mL/min/1.73 m
2
), and severe (<30 mL/min/1.73 m
2
) renal function impairment. The association of renal function with acute stroke severity was analyzed. Logistic regression analysis, Kaplan-Meier method and Cox proportional hazard model were applied to assess factors determining the outcome, recurrent stroke and death at 6 months after stroke.

Results:
Between May, 2006 and April, 2009, there were 7728 patients (male, 61.8%; average age, 68.6 years) with LAA subtype of ischemic stroke. Acute stroke severity (represented as initial NIHSS scores) was correlated significantly with moderate and severe CKD (
P
=0.026 and <0.0001, respectively). The severity of CKD was not significantly related to functional outcome at 6 months after stroke. However, patients with moderate (adjusted hazard ratio, 2.62; 95% confidence interval, 1.18-5.83) and severe (adjusted hazard ratio, 5.48; 95% confidence interval, 2.39-12.56) CKD had higher mortality at 6 months after stroke.

Conclusions:
In patients with LAA of acute ischemic stroke, the severity of CKD at admission is crucial for prediction of 6 months post stroke mortality.
Abstract WP394: Insights Into The Cost-effectiveness Of Blood Pressure Management For Secondary Stroke Prevention
Authors: Young Kate C , Kelly Adam G , Benesch Curtis G , Benavente Oscar
Published: March 2022

Objective:
To determine the relationship between the risk of dementia, risk of recurrent stroke and other factors on the cost-effectiveness of intensive blood pressure management for secondary stroke prevention.

Methods:
A Markov model incorporated data from the PROGRESS trial. It included cost (2011$) and utility estimates from the literature. Intensive management was a 9mmHg reduction in systolic blood pressure compared to usual management. The cost of the additional medications was assumed to be the cost of perindopril. Relative risk terms modified the probability of adverse events with intensive treatment. Outcomes were recurrent stroke, dementia, recurrent stroke with dementia and death. Quality of life with intensive management was lower than usual treatment. Assumptions were tested with one-way and multi-way sensitivity analyses.

Results:
For the base case analysis, the lifetime costs of usual management were $80,200 with 5.626 quality adjusted life years (QALYs). The lifetime costs of intensive management were $85,500 with 5.627 QALYs. The incremental cost-effectiveness ratio (ICER) was $5 million, thus the added costs of intensive management were not offset by increased quality of life. However, this conclusion was sensitive to several assumptions. Intensive management became cost-effective (ICER < $100,000) when (1) ages < 52 years were treated (base case: 64 years), (2) the quality of life with intensive management increased slightly, by 0.01, (3) the cost of BP medications was $270/year, (4) the probability of recurrent stroke was ≥ 5.4% (base case: 3.7%), or (5) the relative risk of recurrent stroke with intensive management was ≤ 0.69 (base case: 0.77). The probability of dementia or the relative risk of dementia did not influence the model. If the cost of medications to lower BP by 9 mmHg was ≤ $260/year, intensive management was dominant with lower lifetime costs and greater QALYs.

Conclusion:
With the base case assumptions, intensive BP management was not the cost-effective choice. Nevertheless cost-effective management can be achieved depending on the age of the cohort and the cost of maintenance medications. This analysis highlights important factors to be considered during the planned cost-effectiveness analysis of the SPS3 trial.
Abstract WP399: Improving Stroke and TIA Care in the Emergency Department: Results from a Provincial Stroke Improvement Collaborative
Authors: Kamal Noreen , Harris Devin , Aikman Pam , Marsden Julian , Krause Christina
Published: March 2022

Background:
Stroke and transient ischemic attack (TIA) are common disorders cared for by emergency physicians. Best practices exist for the management of these disorders; however, these are not always followed.

OBJECTIVES:
This study sought to measure the impact of a coordinated, provincial structured improvement collaborative, on care for stroke and TIA patients within emergency departments (ED’s) in British Columbia.

METHODS:
This study was a qualitative and quantitative process evaluation of a provincial improvement collaborative. The collaborative followed an Institute of Healthcare Improvement (IHI) Methodology, consisting of five workshops, bi-weekly webinars, and improvement coaching and support, over a 10-month period, from Sept 2011 to June 2012. This evaluation examined process measures of success, such as self-reported improvement and adherence to certain clinical process measures (e.g. time to CT). Collaborative participants submitted monthly reports that quantified their improvement using the Self Assessment Score, which is used in IHI Collaborative Methodology.

RESULTS:
17 multidisciplinary teams participated, representing 27% of all ED’s in British Columbia (29 / 108), and all five Health Authorities. Further, all but one of the province’s tPA enabled sites were represented. 90% of teams (15 / 17) reported a median Self Assessment Score greater than 4.5/5.0, indicating significant and sustainable improvements in stroke and TIA care. No teams dropped out of the Collaborative. Teams reported a mean of 5.5 (SD 2.4) significant improvements within their ED. For example, shortened door-to-CT times, improved triage and training, and implementation of standardized swallowing screens were shown. This collaborative showed higher success rates of self-reported improvement (typically only 30% of teams achieve significant improvement) and lower rates of dropouts, than the published literature.

CONCLUSIONS:
Using an IHI structured collaborative format, a provincial stroke & TIA emergency department quality improvement initiative was able to achieve significant improvements in adherence to best practices. A formal outcome evaluation is planned to measure the impact on stroke incidence, disability, and mortality.
Abstract WP408: Patent Foramen Ovale in Childhood Arterial Ischemic Stroke: Prevalence and Stroke Recurrence in a Prospective Cohort
Authors: Ichord Rebecca N , Beslow Lauren A , Kessler Sudha K , Bastian Rachel A , Smith Sabrina E , Licht Daniel J
Published: March 2022

Background and Objectives:
The role of patent foramen ovale (PFO) in childhood arterial ischemic stroke (AIS) is poorly understood. We aimed to define the prevalence of PFO in children with first AIS, and its relationship to recurrence.

Methods:
Subjects (>28 days to <18 years) with AIS between 2006-2012 were identified from a single-center consecutive prospective cohort study. Subjects were excluded with diagnoses of congenital or acquired heart disease, moyamoya, meningitis, brain tumor, surgery of the head or neck, endovascular procedures, metabolic disorder, or hemoglobinopathy. Charts were abstracted for clinical and radiologic features, echocardiogram, and thrombophilia evaluations. Recurrent events included 1) stroke, defined as a new focal deficit with new infarction on imaging, or 2) transient ischemic event (TIA). Incidence of recurrence in children with PFO was compared to those without PFO by survival analysis. Data are given as median (range).

Results:
Forty-four subjects met eligibility criteria, median age 5.8 years (0.1-17), 77% male. Echocardiogram was obtained in 42 (95%), and disclosed a PFO in 7/42 (17%), of which other stroke risk factors were present in 5. In the entire cohort, primary stroke risk factors other than PFO included cervical arterial dissection (8), intracranial focal cerebral arteriopathy (8), thrombophilia (10), CNS vasculitis (1), other (4), none (11). All subjects received antithrombotic treatment for stroke prevention, and 2 underwent endovascular PFO device closure. Follow-up was available in all subjects at median of 25 months (4-71). Incidence rate of recurrent stroke or TIA was 8/1000 - person-months, and was similar in both groups, affecting 1/7 subjects with PFO at 0.3 months, and in 6/37 subjects without PFO at median of 2.8 months (0.3-36) after

first stroke.

Conclusions:
PFO is present in a small proportion of children with first AIS, often with other risk factors. Recurrence in children with PFO in this small cohort was similar to those without PFO. Outcomes may have been influenced by other stroke risk factors, and secondary stroke preventive treatments including PFO closure and antithrombotic treatment. The role of PFO in initial and recurrent stroke remains uncertain, and deserves further study.
Abstract WP41: Peri-Procedural Arterial Spin Labeling and Dynamic Susceptibility contrast Perfusion in Detection of Cerebral Blood Flow in Patients with Acute Ischemic Syndrome
Authors: Nael Kambiz , Meshksar Arash , Liebeskind David S , Wang Danny J , Qiao Joe X , Ellingson Benjamin , Salamon Noriko , Villablanca Pablo J ,   UCLA Stroke Investigators
Published: March 2022

Purpose:
To investigate the potential clinical value and diagnostic performance of arterial spin-labeled (ASL) and dynamic susceptibility contrast (DSC) perfusion in detection of cerebral blood flow (CBF) changes before and after endovascular recanalization in patients with acute ischemic syndrome (AIS).

Methods:
This retrospective study was performed using MR examinations between 2010-2012. Inclusion criteria were: patients with AIS who underwent endovascular recanalization and acquisition of both ASL and DSC before and after revascularization. ASL CBF and multiparametric DSC perfusion maps were qualitatively evaluated for image quality, presence of hypo or hyperperfusion and location of perfusion abnormality. Lesion segmentation for infarct core (ADCb >550) and hypoperfused area (TMax > 4 sec) was performed on DSC. rCBF was calculated using a regions-of-interest (ROI) method in the infarction core and hypoperfused areas using coregistered ASL and DSC images. Core and hypoperfused rCBF ROI’s were used for paired pre- and post-treatment intermodality comparisons. Interobserver and intermodality agreement was evaluated by Kappa test. T-test and Spearman correlation coefficients were calculated for ASL and DSC rCBF values.

Results:
Twenty-five patients were met our inclusion criteria. Five studies were rated non-diagnostic, resulting in a total of 45 pair of DSC-ASL for comparison. ASL and DSC agreed on type of perfusion abnormality in 32 of 45 cases (71%) and location of the perfusion abnormality in 36 of 45 cases (80%). The image quality of ASL was lower than DSC, resulting in interobserver variability for the type (k =0.45) and location (k=0.56) of perfusion abnormality. ASL was unable to show any type of perfusion abnormality in 11% of patients. In patients with successful recanalization, hyperperfusion (rCBF> 1) was detected in 100% on DSC and 47% on ASL. ASL showed prolonged arterial transit effects in 58% of successfully recanalized patients.

Conclusion:
ASL is moderately consistent with DSC for detection of cerebral blood flow changes in patients with AIS. Qualitative and quantitative differences exist between two modalities, in particular in respect to detection of hyperperfusion in successfully recanalized patients.
Abstract WP437: The Relationship Between Cholesterol And Cerebral Vasospasm In A Rat Model Of Subarachnoid Hemorrhage: A Mechanistic Role For Lipid Rafts
Authors: Shirao Satoshi , Yoneda Hiroshi , Ishihara Hideyuki , Yoshino Hiroko , Sugimoto Kazutaka , Koizumi Hiroyasu , Suehiro Eiichi , Shinoyama Mizuya , Oka Fumiaki , Sadahiro Hirokazu , Nomura Sadahiro , Fujii Masami , Kagawa Yoshiteru , Owada Yuji , Suzuki Michiyasu
Published: March 2022

Objective:
Rho-kinase (ROK)-mediated vascular smooth muscle (VSM) contraction plays a pivotal role in cerebral vasospasm (CV). Sphingosylphosphorylcholine (SPC), a sphingolipid, induces ROK-mediated VSM contraction, and hypercholesterolemia increases SPC-ROK-mediated VSM contraction. Lipid rafts are cholesterol-enriched membrane microdomains that influence signal transduction. In this study, we report the effect of cholesterol and lipid rafts on CV.

Methods:
Adult male Sprague-Dawley rats (400-500g, n=53) were fed control, 1% cholesterol or 1% cholesterol +5% β-cyclodextrin (β-CD), which depletes VSM cholesterol, diets for 8 weeks. We used a double-hemorrhage rat subarachnoid hemorrhage (SAH) model, and investigated CV of the basilar artery (BA) at Day5 using a cranial window. T-Cho levels in the internal carotid artery (ICA) were measured using Gas Chromatography. The expression of Flotillin-1, a raft marker, and Flotillin-1 mRNA in the ICA were analysed by Western blot and real-time RT-PCR, respectively.

Results:
The BA diameters were 358.94±32.05μm and 302.21±38.36μm in control diet (non-treated) and SAH rats, respectively (n=9/group, p<0.05 vs. non-treated). SAH-induced BA contraction was markedly reversed by intracisternal infusion of 10μM Y27632 (n=4, p<0.05), a ROK inhibitor. The BA diameter in SAH rats fed the cholesterol diet was 248.11±34.56μm (n=6, p<0.05 vs. control SAH-rats), compared with 305±25.28μm in SAH rats fed a β-CD diet (n=6, p<0.05 vs. SAH-rat fed a cholesterol diet). T-Cho levels in the ICA were significantly higher in rats fed a cholesterol diet compared with the control diet (0.82±0.24 vs. 0.49±0.09mg/g, n=5/group, p=0.028) or the β-CD diet (0.47±0.06 mg/g, n=5, p=0.016 vs. cholesterol diet). Western blot analysis and real-time RT-PCR revealed increases in Flotillin-1 and Flotillin-1 mRNA expression in the ICA from rats fed a cholesterol diet, whereas Flotillin-1 and Flotillin-1 mRNA expression were not altered in the ICA from rats fed the β-CD diet.

Conclusions:
These results indicate that cholesterol potentiates SAH-induced CV and are compatible with a role for lipid rafts in this process.
Abstract WP448: Cognitive Deficits In Patients With Aneurysmal Subarachnoid Hemorrhage Can Be Screened By Montreal Cognitive Assessment And Correlate With Functional Outcomes
Authors: Wong George K ,   Cognitive Dysfunction after Aneurysmal Subarachnoid Hemorrhage Investigators
Published: March 2022

Objective:
Cognitive impairment after aneurysmal subarachnoid hemorrhage (aSAH) is common and important for patient management (medical treatment, cognitive rehabilitation, and social arrangements). The Montreal Cognitive Assessment (MoCA) was recently applied as the screening test for vascular cognitive impairment after acute ischemic stroke. We hypothesized that cognitive deficits in patients with aneurysmal subarachnoid hemorrhage can be screened by Montreal Cognitive Assessment and correlate with functional outcomes.

Methods:
We carried out a prospective observational and diagnostic accuracy study in Hong Kong over a 38 month period, and recruiting 173 patients aged 21 to 75 years with aSAH admitted within 96 hours of ictus. The assessments are domain-specific neuropsychological assessment battery, MoCA, MMSE, modified Rankin Scale, and Lawton Instrumental Activity of Daily Living at 2-4 weeks (n=74) and 1 year (n=80) after ictus. The current study is registered at ClinicalTrials.gov of the U.S. National Institutes of Health (
NCT01038193
).

Results:
Unfavorable outcome (mRS 3-5) and dependent instrumental activity of daily living (IADL<15) correlated with visuospatial memory and skill and language domain deficits at 2-4 weeks and with significant cognitive impairment and all cognitive domain deficits except attention and working memory at 1 year. At 2-4 weeks, the AUCs were similar between MoCA and MMSE for cognitive domain deficits and cognitive impairment; at 1 year, MoCA had higher AUCs than MMSE for significant cognitive impairment and all cognitive domain deficits except visuospatial memory and skill.

Interpretation:
Cognitive deficits in patients with aneurysmal subarachnoid hemorrhage can be screened by MoCA and correlate with functional outcomes in both subacute and chronic phases.
Abstract WP5: Collaterals in the Interventional Management of Stroke (IMS) III Trial
Authors: Liebeskind David S , Tomsick Thomas A , Yeatts Sharon , Foster Lydia , Carrozzella Janice , Jovin Tudor G , Khatri Pooja , Goyal Mayank , Palesch Yuko , Broderick Joseph P ,   for the IMS III Investigators
Published: March 2022

Background:
Collateral circulation may exert an influential effect on arterial recanalization, downstream angiographic and tissue reperfusion and ensuing clinical outcomes after revascularization for acute ischemic stroke. Endovascular strategies provide unique opportunity to correlate definitive angiographic measures of collaterals at the time of interventional therapy. We conducted a systematic analysis of collaterals on conventional angiography in the endovascular treatment arm of the Interventional Management of Stroke (IMS) III trial.

Methods:
Prospective evaluation of angiographic collaterals was conducted via central review of all cases enrolled and treated in the endovascular arm of IMS III. Collateral grade was assessed with the ASITN/SIR scale on angiography at procedure start and immediately prior to intra-arterial treatment (time 0), blind to all other data. Statistical analyses investigated the association between collateral grade with baseline clinical data, angiographic measures of recanalization (AOL), angiographic reperfusion (TICI), and clinical outcomes.

Results:
From 2006-2012, 380 cases were prospectively evaluated for collateral grade at start of procedure and time 0 prior to treatment. Adequate collateral views were available in 283/380 (75%) cases at baseline, and 277/380 (73%) cases at time 0 and after subsequent treatment with intra-arterial tPA, EKOS, MERCI, Penumbra, and Solitaire devices. Detailed results will be presented at ISC in coordination with release of the primary trial results. The relationships between collateral flow grade and baseline clinical features (NIHSS and age), location of vascular occlusion at cerebral angiography, AOL recanalization and TICI reperfusion, and mROS of 0-2 at 90 days will be presented. Analyses will explore potential interactions between collateral flow grade with recanalization, angiographic reperfusion, and clinical outcome.

Conclusions:
Collateral circulation was available and prospectively evaluated in the largest endovascular therapy trial for stroke conducted to date. The role of collaterals may be an important consideration in the design of future endovascular trials.
Abstract WP54: Defining Acute Ischemic Stroke Tissue Pathophysiology Using Whole Brain 320 Slice Ct Perfusion
Authors: Bivard Andrew , Parsons mark
Published: March 2022

Background:
Imaging with Computed tomography perfusion (CTP) in acute stroke has recently started to gain ground, however it requires further validation and whole brain CTP scanners are becoming more available. This study aimed to validate the optimal acute ischemic stroke whole brain CTP pathophysiology parameters.

Methods:
One hundred and thirteen patients were scanned within 6 hours of ischemic stroke onset with 320 slice CT, which allows concurrent whole brain CTP and dynamic intracranial CT angiography to be derived from the one acquisition. Patients were then followed with a 24 hour MRI sequence that included diffusion weighted imaging (DWI) and dynamic susceptibility weighted perfusion imaging (PWI). Coregistered acute CTP and 24 hour DWI images were then used to define the optimum CTP perfusion threshold for identifying the extent of critically hypoperfused tissue, and infarct core using a pixel based receiver operator curve analysis in patients with and without reperfusion at 24 hours.

Results:
A time to peak TTP threshold of +5 seconds from contralateral baseline defined the perfusion lesion (AUC 0.79 CI 0.74-0.83) while a Cerebral blood flow < 50% from contralateral baseline best defined the acute infarct core (AUC 0.75, CI, 0.71-0.79). There was no statistically significant difference between the accuracy of thresholds depending on the level or region of the brain to define tissue pathophysiology.

Discussion:
Whole brain CTP can identify critically hypoperfused tissue and the acute infarct core with excellent accuracy, and finally overcomes the major problem of limited slice coverage with CTP with previous generation CT scanners.
Abstract WP65: Outcomes Of Thrombolytic Treatment For Acute Ischemic Stroke In Dialysis Dependant Patients In The United States
Authors: Tariq Nauman , Chaudhary Saqib , Adil Malik M , Saeed Maryam , Qureshi Adnan I
Published: March 2022

Objective:
To determine the outcomes of dialysis dependant patients who suffered from ischemic stroke and were treated with IV thrombolytics in United States

Methods:
We analyzed the data from Nationwide Inpatient Sample (NIS 2005-2008) for all thrombolytic treated patients presenting with acute ischemic stroke with or without dialysis dependence. Patients were identified using the ICD 9 CM codes. Baseline characteristics, inhospital complications including secondary intracerebral hemorrhage (ICH), DVT, UTI, sepsis, pneumonia, sepsis, pulmonary embolism and discharge outcomes (mortality, minimal disability, and moderate to severe disability) were compared between the groups.

Results:
Of the 82142 patients with ischemic stroke who receive thrombolytic treatment, 1072 (1.3%) was dialysis dependent. Out of 4215004 patients with ischemic stroke who did not receive thrombolytic treatment, 61400 (1.4%) were dialyses dependent. Baseline characteristics were mainly age, sex, race, medical comorbidities including hypertension, diabetes mellitus, presence of congestive heart failure and chronic lung diseases. The ICH rates did not differ significantly between patients with ischemic stroke with or without dialysis who received thrombolytics (5.2% vs 6.1%)The in-hospital mortality rate was higher in dialysis dependent patients treated with thrombolytics. (22% vs 11%) (P <.0001). After adjusting for age and sex, and co morbidities, dialysis dependence was associated with higher rates of in-hospital mortality in patients treated with thrombolytics (odds ratio [OR], 2.47; 95% CI, 1.80-3.38 vs. odds ratio [OR], 3.06; 95% CI, 2.86-3.26).

Conclusions:
The three fold higher odds of in-hospital mortality associated with administration of IV thrombolytics in dialysis dependant patients who present with acute ischemic stroke warrants a careful assessment of risk benefit ratio in this population.
Abstract WP66: Metalloproteinase-9 Higher Increase After Thrombolysis Is Associated With Hemorrhagic Transformation Of Lesion And With Poor Stroke Outcome
Authors: Inzitari Domenico , Giusti Betti , Nencini Patrizia , Gori Anna M , Nesi Mascia , Palumbo Vanessa , Piccardi Benedetta , Armillis Alessandra , Pracucci Giovanni , Abbate Rosanna ,   for the MAGIC study group
Published: March 2022

Background and Purpose:
In experimental animals metallo-proteinases (MMPs) play a detrimental role related to severity and hemorrhagic transformation of the ischemic lesion. tPA enhances and MMPs inhibitors (TIMPs) antagonize such effects. This study aimed to expand clinical evidence in this connection.

Methods:
Blood was taken at baseline and 24 hours after from 327 patients (mean age 68, mean NIHSS 11.9) with acute ischemic stroke, all treated with i.v. tPA thrombolysis within 4.5 hours. MMPs 1, 2, 3, 7, 8, 9, and TIMPs 1, 2, 4 were measured (in ng/ml) using Bio-plex suspension array system and R&D kits. Delta median values [(post tPA-baseline)/baseline] of each MMP or TIMP were analyzed related to symptomatic hemorrhage (SICH), death, 3 month mRS (3-6 vs. 0-2), and correlated with baseline, 24 hours and 7 days NIHSS.

Results:
delta increases: 1) SICH vs. non SICH: significant for MMP9 and TIMP4 [MMP-9: 0.38 vs. -0.18 p 0.006; TIMP4 0.67 vs. 0.22 p 0.015]. 2) Death vs. survival: significant for MMPs 1, 8, 9 and TIMP1 [MMP1: 0.01 vs. -0.14 p .048; MMP8: 0.46 vs. -0.09 p .011; MMP9: 0.37 vs. -0.17 p .007; TIMP1 0.17 vs. -0.02 p .011]. 3) mRS 3-6 vs. 0-2: significant for MMPs 8, 9, and TIMP 4 [MMP8: 0.12 vs. -0.17 p<.001; MMP9: 0.11 vs. -0.21 p<.001; TIMP4 0.50 vs 0.16, p<.001]. Both MMP-9 and TIMP4 deltas were strongly correlated with baseline, 24h, and 7 days NIHSS (Spearman p ranging from .003 to .001). Adjusting for demographics, baseline glucose or NIHSS, infection and atrial fibrillation, only MMP-9 remained an independent determinant of death [OR (95% CI) 1.55 (1.08-2.21)], SICH [OR (95% CI) 1.38 (1.01-1.90)], or mRS 3-6 [OR (95% CI) 1.35 (1.01-1.80)].

Conclusions:
our data add substantial clinical evidence about MMP-9 as detrimental factor in ischemic stroke treated with thrombolysis, and may prompt RCTs testing of TIMPs in combination with tPA.
Abstract WP70: Do Stroke Patients benefit from Thrombolysis despite Contraindications or Warnings?
Authors: Frank Benedikt , Grotta James C , Alexandrov Andrei V , Bluhmki Erich , Lyden Patrick , Meretoja Atte , Mishra Nishant K , Shuaib Ashfaq , Wahlgren Nils G , Weimar Christian , Lees Kennedy R ,   on behalf of the VISTA Collaboration
Published: March 2022

Background&Purpose:
Intravenous thrombolysis with alteplase is approved for acute ischemic stroke but its use is limited by numerous contraindications and warnings arising from trial selection criteria and/or expert opinions. We examined outcomes from alteplase-treated versus untreated patients from neuroprotectant trials held within a trials archive called VISTA, according to presence or absence of specified contraindications and warnings.

Subjects&Methods:
We analysed 90 day modified Rankin scale across the whole distribution of scores using the Cochran-Mantel-Haenszel (CMH) test, with adjustment for age and baseline NIHSS, followed by proportional odds logistic regression analysis to estimate the odds ratios for preferred outcome. We gathered data from 9613 ischemic stroke patients, of whom 4793 patients (49.6%; 1281 thrombolysed, 3512 non-thrombolysed) had at least one known contraindication, and 6231 (64.8%; 1946 thrombolysed, 4285 non-thrombolysed) had at least one known contraindication or warning for treatment with alteplase.

Results:
A broad trend of more favourable 3-month outcome associated with alteplase treatment in various subgroups of patients with contraindications or warnings was evident; eg in patients aged >80 (n=1805; OR 1.40; 95% CI 1.14-1.70; p <0.001), with combined history of prior stroke and diabetes (n=672; OR 1.50; 1.03-2.18; p=0.03), on prior single antiplatelet agent (n=1626; OR 1.42; 1.19-1.70; p 180 mg/dl (n=879; OR 1.50; 1.15-1.97; p=0.002) or with major early computed tomographic changes (n=176; OR 2.46; 1.28-4.72; p=0.01). Results were inconclusive after mild stroke, NIHSS<6 (n=381; OR 0.97; 0.50-1.87; p=0.76).

Conclusions:
This retrospective analysis of various contraindications and warnings provides reassurance about benefits and risks of intravenous alteplase treatment in common clinical situations.
Abstract WP80: Cocaine Use and Aneurysmal Subarachnoid Hemorrhage
Authors: Normen-Smith Ingrid O , Gandhi Chirag D , Hidalgo Andrea , Prestigiacomo Charles J
Published: March 2022

INTRODUCTION:
There have been many reports of aneurysmal subarachnoid hemorrhage (aSAH) associated with cocaine, but few studies that actually address cocaine’s influence on aSAH. [3] Hypertension is an accepted contributor to aneurysm rupture and has been associated with the prevalence of rupture in a younger, cocaine-using, population. [1-3] A literature search revealed only one study that correlated aneurysm size at rupture and cocaine use. [2] This study will retrospectively evaluate the relationship between cocaine use and aneurysm size at rupture in our aSAH patient population.

METHODS:
All aSAH patients from September of 2009 through May of 2011 were reviewed at our hospital for 22 parameters that included sex, age, race, cocaine use, aneurysm size, carotid stenosis, diabetes mellitus, heart failure, hypertension, previous stroke, sickle cell disease, smoker, etc. To date only average aneurysm size was compared between the the cocaine and non-cocaine-using population using measurements from angiography reports.

RESULTS:

In this period, 91 aSAH patients were seen at our hospital with seven positive screens for cocaine. Average aneurysm size for cocaine users was 3.7mm and 6.2mm for non-cocaine users. This was statistically significant.

CONCLUSION:
Our cocaine-using patient population had an average aneurysm size much smaller than the non-cocaine-using patients. For the future, a retrospective meta-analysis using our covariates will be conducted to determine whether cocaine presents an independent risk factor for aSAH.

BIBLIOGRAPHY:

1. Oyesiku, N.M., et al., Cocaine-induced aneurysmal rupture: an emergent negative factor in the natural history of intracranial aneurysms? Neurosurgery, 1993. 32(4): p. 518-25; discussion 525-6.

2. Nanda, A., et al., Intracranial aneurysms and cocaine abuse: analysis of prognostic indicators. Neurosurgery, 2000. 46(5): p. 1063-7; discussion 1067-9.

3. Howington, J.U., et al., Cocaine use as a predictor of outcome in aneurysmal subarachnoid hemorrhage. J Neurosurg, 2003. 99(2): p. 271-5.
Abstract WP86: Anterior Communicating Artery Cerebral Aneurysms, 10-year Treatment Experience at a Tertiary Referral Medical Center: Large Prevalence of Ruptured Small Aneurysms
Authors: Nelson Jeffrey T , Manjila Sunil , Lee Eric S , Bambakidis Nicholas C , Selman Warren R , Blackham Kristine A
Published: March 2022

Purpose
To determine patient characteristics and size distribution among ruptured and unruptured anterior communicating artery (AComA) aneurysms less than 7 mm treated with coiling or clipping in a 10-year time period at a tertiary referral medical center. A secondary objective is comparison of institutional data to published ISUIA data of 0% 5-year cumulative rupture risk for anterior circulation aneurysms < 7 mm.

Materials & Methods
We retrospectively reviewed AComA aneurysm characteristics in all patients who were treated with coiling or clipping from December 2002 until June 2012. Aneurysm location and maximum sac diameter were recorded utilizing catheter angiography or computed tomography angiography.

Results
In our series, 180 AComA aneurysms were treated from 12/2002 to 6/2012. 123 (68.0%) AComA aneurysms were treated in the setting of nontraumatic subarachnoid hemorrhage (SAH) while 57 (32.0%) were treated electively. Table 1 shows the characteristics of the AComA aneurysms in our series. Table 2 shows the size breakdown of ruptured and unruptured AComA aneurysms.

Table 1. AComA Aneurysm Characteristics.

Table 2. AComA Aneurysm Size Breakdown

Conclusion
Among ruptured AComA aneurysms, 61.0% had a maximum diameter < 7 mm, while 35.0% were < 5 mm, which argues against the reported low risk of rupture in aneurysms < 7 mm based on the ISUIA trial. Further studies are recommended to correlate risk of rupture with such factors as personal or family history of subarachnoid hemorrhage, medical comorbidities, and documented growth of aneurysm.
Abstract WP88: Predictors of Outcome for Procedural Perforation During Coiling of Intracranial Aneurysms: A Single Center Experience
Authors: Hage Ziad A , Alaraj Ali , Amin-Hanjani Sepideh , Aletich Victor A
Published: March 2022

Background:
Despite significant advances in coil embolization of intracranial aneurysms (IA), intra-procedural perforation (IPP) remains a dreaded complication associated with significant morbidity (up to 50%) and mortality (up to38%).

Objective:
In this study, we sought to analyze all IPP during IA coiling at our center over a 10 year period to determine what characteristics may predict outcome.

Methods:
This is a retrospective chart review of 1029 consecutive patients who underwent IA coiling from January 2002-May 2012. Variables evaluated included clinical presentation, aneurysm location, morphological aspects and neurological outcomes at discharge. Good outcomes were defined as modified Rankin scale (mRS) 1-3.

Results:
IPP occurred in 24 patients (2.3% of the cohort). Of all IPP, 83% occurred in previously ruptured IA, 17% in unruptured IA. This corresponded to an overall IPP rate of 4% and 0.8% respectively. Overall morbidity at discharge (mRS 4,5) was 31.8% and mortality 8.3%. Overall, good outcome was noted in 44.4% immediately post-procedure and 68.2% at discharge. Among patients with unruptured IA and those with good Hunt-Hess (HH) grade (1-3), 92% had good outcome at discharge vs. 54.6% with poor HH,
p=0.03.
Patients with proximal IA (proximal to internal carotid artery bifurcation or close to basilar artery stem) had better discharge outcomes (41.7%) than distal IA (33.3%),
p=
0.04; this was statistically significant after controlling for HH in logistic regression analysis. Between 2002-2007, balloon-assisted coiling (BAC) was utilized in only 20% of IPP cases and 2 mortalities were recorded. After 2007, BAC was used in 60% of IPP cases with no subsequent mortalities.

Conclusion:
It appears that the incidence of IPP is very low, with good outcomes occurring in a significant portion of the patients. Patients with good neurological exam at presentation are likely to have good discharge outcomes despite IPP. Proximal IA are associated with better discharge outcomes: IPP in this location may be easier to control endovascularly. Techniques like BAC allow for prompt hemostasis once IPP occurs, and might reduce mortality rates.
Abstract WP98: Microglia/macrophage Polarization Dynamics Reveal Novel Mechanism Of Injury Expansion After Focal Cerebral Ischemia
Authors: Hu Xiaoming , Li Peiying , Guo Yanling , Wang Haiying , Gao Yanqin , Chen Jun
Published: March 2022

INTRODUCTION:
Mononuclear phagocytes are highly plastic cells that assume diverse phenotypes in response to microenvironmental signals. The phenotype-specific roles of microglia/macrophages in ischemic brain injury are poorly understood.

METHODS:
Cerebral ischemia was induced in mice by unilateral middle cerebral artery occlusion (MCAO) for 60 min; animals were sacrificed on Day 1 to Day 14 of reperfusion. RT-PCR and immunohistochemical staining for M1 and M2 microglia/macrophage markers were performed to characterize phenotypic changes.
In vitro
experiments using a transwell system, a conditioned medium transfer system, or a coculture system allowing cell-to-cell contacts were employed to further elucidate the effect of neuronal ischemia on microglia polarization and, conversely, the effect of microglia phenotype on the fate of ischemic neurons.

RESULTS:
The levels of M1 specific genes (iNOS, CD11b, CD16, CD32 and CD86) gradually increased over time from day 3 onwards and remained elevated for at least 14 days after ischemia. In contrast, the expression of M2 genes (CD206, Arg1, CCL22, Ym1/2, IL-10 and TGFβ) was induced since day 1, began to drop at day 7 and returned to pre-injury levels by day 14 after MCAO. Double immunofluorescent staining of microglia/macrophage marker Iba-1 with CD206 or CD16/32 confirmed that Iba-1+ cells assume the M2 phenotype at early stages of ischemic stroke but gradually transformed into the M1 phenotype in peri-infarct regions.
In vitro
experiments revealed that ischemic neurons prime microglial polarization towards M1 phenotype. M1-polarized microglia or M1-conditioned media exacerbated oxygen glucose deprivation (OGD)-induced neuronal loss. In contrast, maintaining the M2 phenotype of microglia protected neurons against OGD.

CONCLUSIONS:
Our results suggest that microglia/macrophages respond dynamically to ischemic injury, experiencing an early "healthy" M2 phenotype followed by a transition to a "sick" M1 phenotype. These dual and opposing roles of microglia/macrophages suggest that stroke therapies should be shifted from simply suppressing microglia/macrophage towards adjusting the balance between beneficial and detrimental microglia/macrophage responses.
Abstract 116: Migraineurs Are More Susceptible to Infarct Growth in Acute Stroke
Authors: Eikermann-Haerter Katharina , Park Kwangyeol , Helenius Johanna , Velioglu Murat , Daneshmand Ali , Arsava Murat , Pearlman Lea , Ross Avery , Negro Andrea , Ayata Cenk , Ay Hakan
Published: March 2022

Epidemiological data indicate that migraine is an independent stroke risk factor. Recent data suggest that migraine mutations increase brain vulnerability to ischemia via excitatory mechanisms (Circulation 2012; 125:335). Migraine mutant mice developed higher number of ischemic depolarizations and accelerated infarct growth during hyperacute stroke, with worse tissue and neurological outcomes.

Here, we retrospectively assessed acute stroke evolution in patients with a reliably documented migraine history. In a blinded fashion, we analyzed the lesion volume on diffusion-weighted imaging (DWI), and the volume of perfusion defect on perfusion-weighted imaging (PWI) using mean transit time (MTT), from consecutive patients during the years 2003-2012 in the Massachusetts General Hospital stroke database. DWI-PWI mismatch was calculated on spatially co-registered DWI and MTT maps, as a marker for viable tissue at risk for infarction.

A total of 155 stroke patients had reliably documented presence or absence of a migraine history. Stroke patients with a history of migraine were younger and more often female, compared to stroke patients who never suffered from migraine. Migraineurs less frequently had coronary artery disease or diabetes. The frequency of posterior circulation lesions was significantly higher in migraineurs. Otherwise, groups were comparable.

In migraineurs with aura, a larger proportion of the perfusion defect showed DWI changes, resulting in smaller DWI/PWI mismatches. A significantly larger proportion of migraineurs with aura showed no mismatch (i.e., DWI/PWI>0.9), indicating that the entire perfusion defect was already infarcted (Table).

Our data show that a history of migraine, particularly with aura, is associated with accelerated acute infarct growth, consistent with data obtained in migraine mutant mice.

[Table. Diffusion-perfusion mismatch. *p=0.011 migraine vs no migraine,
†
p=0.002 migraine with aura vs no migraine]
Abstract 128: Intracisternal Administration of Tissue Plasminogen Activator Improves Cerebrospinal Fluid Flow and Cortical Perfusion After Subarachnoid Hemorrhage in Mice
Authors: Siler Dominic A , Gonzalez Jorge A , Wang Ruikang K , Cetas Justin S , Alkayed Nabil J
Published: March 2022

Early brain injury (EBI) during the first 72 hours after subarachnoid hemorrhage (SAH) is a key determinant of clinical outcome. A hallmark of EBI, global cerebral ischemia, occurs within seconds of SAH and is thought to be related to increased intracranial pressure (ICP). We tested the hypothesis that ICP elevation and cortical hypoperfusion after SAH are the result of physical blockade of cerebrospinal fluid (CSF) flow pathways by cisternal microthrombi. In mice subjected to SAH, we measured cortical blood volume (CBV) using optical imaging, ICP using pressure transducers and patency of CSF flow pathways using intracisternally injected tracer dye. We then assessed the effects of intracisternal recombinant tissue plasminogen activator (tPA). ICP rose immediately after SAH and remained elevated for 24 hours. This was accompanied by decreased CBV and impaired dye movement
.
Intracisternal administration of tPA immediately after SAH lowered ICP (from 34.8 ± 3.7 (n=5) to 17.5 ± 3.1 mmHg, (n=6)), increased CBV (from 51.5 ± 8.9 (n=5) to 80 ± 4.7 % of baseline, (n = 6)) and partially restored CSF flow at 24 hours after SAH. Lowering ICP without tPA, by draining CSF, improved CBV at 1, but not 24 hours. These findings suggest that blockade of CSF flow by microthrombi contributes to the early decline in cortical perfusion in an ICP-dependent and independent manner, and that intracisternal tPA may reduce EBI and improve outcome after SAH.

Figure 1. tPA reduces ICP and improves perfusion after SAH
. A) Representative perfusion images of the cortex at baseline, 1h post SAH/sham (pre-treatment), and 24h post-SAH/Sham (post-treatment). B) ICP at 1h pre-treatment and 24h post-treatment. C) Quantification of perfused CBV 1h pre-treatment and 24h post-treatment. Sham (n =3), SAH vehicle (n =5), SAH tPA (n = 6) * = P <0.05 Scale bar = 500 um