bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract TMP104: Left Atrial Dilatation, Atrial Fibrillation And Stroke, A 5 Year Follow Up Study
Authors: Aboul Nour Hassan , Jum'ah Ammar , Affan Muhammad , Gagi Karam , Schultz Lonni , Brady Megan , Scozzari Dawn , Miller Daniel
Published: February 2022

Background:
Our prior study showed that Atrial Fibrillation (AFib) and not Left Atrial Dilatation (LAD) was associated with ischemic stroke (IS) in a cross-sectional analysis. We sought to validate these findings in a prospective 5-year follow up study.

Methods:
Patients with transthoracic ECHO (TTE) completed from March-September 2016 were selected. We obtained new diagnoses of Afib and IS over the interval period of 5 years (2016-21). Regression models were used to analyze LAD, Afib and other covariates as they relate to IS, as well as the association of baseline LAD to subsequent AFib.

Results:
There were 7988 subjects analyzed. Of those we excluded; 578 had IS before 2016 and an additional 249 patients had no follow-up data. Of the remaining 7161, mean age was 65, 54% females, 52% Caucasian, 43% African American, 9% developed new AFib and 3% had a new IS during follow-up. The median follow-up was 47 months. Also, 54% patients had a normal LA, 13% were mildly, 13% were moderately and 20% were severely dilated, of which 6, 11, 13 and 15% were found to have new AFib, respectively (p<0.001). Mild and severe LAD was more likely to experience IS when compared to normal LAD (Model-1:p=0.02 (HR 1.5, 95%CI 1.06-2.3) and p<0.0003 (HR 1.8, 95%CI 1.3-2.5) respectively), and moderate LAD showed a trend (p=0.08). Prior diagnosis of LAD or Afib was associated with a new IS on univariate analysis (Model-2:p<0.0001). However, on multivariate analysis, considering both LAD and Afib in the same model, only Afib remained associated with IS (Model-3: p<0.0001 (HR 1.8, 95%CI 1.3-2.5)) and remained significant even after adjusting for other covariates (Model-4: HR 2.2, 95%CI 1.5-3.3, p=<0.001). Additionally, anticoagulant use was associated with a reduced risk of IS. (HR 0.6, 95%CI 0.4-0.9, P=0.01)

Conclusion:
LAD increased the probability of AFib discovery during follow-up and was associated with both Afib and IS. However, AFib, not LAD, was independently associated with IS. Medical treatment of AFib was associated with a reduction in future IS, reaffirming the need to identify and treat AFib. Our study suggests the presence of LAD on TTE is a useful marker for identification of high risk individuals for Afib and prospective investigations to identify Afib would provide primary IS prevention.
Abstract TMP110: Impairment Of Efferocytosis Promotes The Rupture Of Intracranial Aneurysm
Authors: Take Yushiro , Miyamoto Takeshi , Sato Hiroki , Ai Jinglu , Lawton Michael , Hashimoto Tomoki N
Published: February 2022

Background:
Efferocytosis is an apoptotic cell clearing process that reduces the tissue-damaging effects of excessive apoptotic cells. Mer receptor tyrosine kinase (Mertk) is present on the surface of phagocyte cells, such as macrophages, and mediates efferocytosis of apoptotic cells. Cleavage of Mertk by metalloproteinases impairs efferocytosis. Several studies suggested that the severity of atherosclerosis, myocardial infarction, and aortic aneurysms were increased in Mertk KO mice due to the impairment of efferocytosis. Higher levels of apoptosis are found in ruptured aneurysms compared to in unruptured aneurysms, suggesting impaired efferocytosis in rupture-prone aneurysms. However, whether impaired efferocytosis plays a role in the pathophysiology of intracranial aneurysms is unclear. In this project, we investigated the effect of impaired efferocytosis in intracranial aneurysms.

Hypothesis:
We hypothesize that impairment of efferocytosis promotes the rupture of intracranial aneurysms.

Methods:
We induced intracranial aneurysms by combining systemic hypertension and a single injection of elastase into the cerebrospinal fluid in mice. Aneurysm rupture rate was used as the primary endpoint. We used Mertk knockout (KO) mice.

Results:
There was no statistical difference in the formation rate of aneurysms between litter-mate control wild-type mice (WT) and Mertk KO mice. Interestingly, the aneurysmal rupture rate was significantly higher in Mertk KO mice (Mertk vs. WT: 94.7% vs. 61.5%, P < 0.05%).

Conclusions:
Our experiment suggested that impairment of efferocytosis promotes aneurysm rupture. Inhibiting cleavage of Mertk may be a strategy for preventing the rupture of intracranial aneurysms.
Abstract TMP13: Risk Stratification Models For Stroke In Patients Hospitalized With Covid-19 Infection: An American Heart Association Covid-19 CVD Registry Study
Authors: Merkler Alexander E , Zhang Cenai , Diaz Ivan , Stewart Carolyn , Mir Saad , Parikh Neal S , Murthy Santosh , Lin Ning , Gupta Ajay , Iadecola Costantino , Elkind Mitchell S , Kamel Hooman , Navi Babak
Published: February 2022

Introduction:
Coronavirus Disease 2019 (COVID-19) is associated with an increased risk of stroke and worse stroke outcomes. A clinical score that can identify high-risk patients could enable closer monitoring and targeted preventative strategies.

Methods:
We used data from the AHA’s COVID-19 CVD Registry to create a clinical score to predict the risk of stroke among patients hospitalized with COVID-19. We included patients aged >18 years who were hospitalized with COVID-19 at 122 centers from March 2020-March 2021. To build our score, we used demographics, preexisting comorbidities, home medications, and vital sign and lab values at admission. The outcome was a cerebrovascular event, defined as any ischemic or hemorrhagic stroke, TIA, or cerebral vein thrombosis. We used two separate analytical approaches to build the score. First, we used Cox regression with cross validation techniques to identify factors associated with the outcome in both univariable (p<0.10) and multivariable analyses (p<0.05), then assigned points for each variable based on corresponding coefficients. Second, we used regularized Cox regression, XGBoost, and Random Forest machine learning techniques to create an estimator using all available covariates. We used Harrel’s C-statistic to measure discriminatory performance.

Results:
Among 21,420 patients hospitalized with COVID-19 (mean age 61 years, 54% men), 312 (1.5%) had a cerebrovascular event. Using traditional Cox regression, we created and internally validated a risk stratification score (CANDLE) (Fig) with a C-statistic of 0.66 (95% CI, 0.60-0.72). The machine learning estimator had similar discriminatory performance, with a C-statistic of 0.69 (95% CI, 0.65-0.72). For ischemic stroke or TIA, CANDLE’s C-statistic was 0.67 (95% 0.59-0.76).

Conclusion:
We developed an easy-to-use clinical score, with similar performance to a machine learning estimator, to help stratify stroke risk among patients hospitalized with COVID-19.
Abstract TMP16: Covid-19 And Risk Of Acute Ischemic Stroke Among Medicare Beneficiaries: Self-controlled Case Series Study
Authors: Yang Quanhe , Tong Xin , George Mary G , Chang Anping , Merritt Robert K
Published: February 2022

Introduction:
Findings of association between COVID-19 and stroke remain inconsistent, ranging from significant association, absence of association to less than expected ischemic stroke among hospitalized patients with COVID-19. The present study examined the association between COVID-19 and risk of acute ischemic stroke (AIS).

Methods:
We included 19,553 Medicare fee-for-service (FFS) beneficiaries aged ≥65 years diagnosed with COVID-19 between April 1 and November 30, 2020 and AIS hospitalization from January 1, 2019 through November 30, 2020. We used a self-controlled case series design to examine the association between COVID-19 and AIS and estimated the incident rate ratios (IRR) by comparing incidence of AIS in risk periods (0-3, 4-7, 8-14, 15-28 days after diagnosis of COVID-19) vs. control periods.

Results:
Among 19,553 Medicare FFS beneficiaries with COVID-19 and AIS, the median age at diagnosis of COVID-19 was 80.5 (interquartile range 73.6-87.3) years and 57.5% were women. IRRs at 0-3, 4-7, 8-14, and 15-28 days following COVID-19 diagnosis were 10.97 (95% confidence interval 10.30-11.68), 1.59 (1.35-1.87), 1.23 (1.07-1.41), and 1.06 (0.95-1.18), respectively. The association appeared to be stronger among younger beneficiaries and among beneficiaries without prior history of stroke but largely consistent across sex and race/ethnicities.

Conclusions:
Risk of AIS among Medicare FFS beneficiaries was ten times as high during the first 3 days after diagnosis of COVID-19 as during the control period and the risk associated with COVID-19 appeared to be stronger among those aged 65-74 years and those without prior history of stroke.
Abstract TMP3: Long-term Outcomes From The Pipeline Embolization Devices For The Treatment Of Intracranial Aneurysms (PEDESTRIAN) Registry With Ped Shield Sub-analysis
Authors: Lylyk Ivan , Scrivano Esteban , Nella Castro Rodolfo , Lundquist javier , Perez Nicolas , Veloso Sebastian , Federico Daiana , Cardenas Andres , Diaz Figueroa Juan Ignacio , Roussell Mauricio , Muñoz Rodrigo , Lylyk Pedro N , Bleise Carlos , Lylyk Pedro
Published: February 2022

Background:
Prospective studies have established the safety and efficacy of the Pipeline
TM
Embolization Device (PED) for treatment of intracranial aneurysms (IA).

Objective:
To investigate long-term outcomes from the Pipeline Embolization Devices for the Treatment of Intracranial Aneurysms (PEDESTRIAN) Registry.

Methods:
The PEDESTRIAN registry data was retrospectively reviewed, which included patients (March 2006-July2019) with complex IAs treated with PED. The primary angiographic endpoint was complete occlusion and long-term stability. Clinical and radiological follow-up was performed at 3-6 months, 12 months, and yearly thereafter.

Results:
A total of 835 patients (mean age 55.9±14.7 years; 80.0% female) with 1,000 aneurysms were included. Aneurysms varied in size: 64.6% were small (≤10mm), 25.6% were large (11-24mm), and 9.8% were giant (≥25mm). A total of 1,214 PEDs were deployed. Follow-up angiography was available for 85.1% of patients with 776 aneurysms at 24.6±25.0 months (mean). Complete occlusion was demonstrated in 75.8% of aneurysms at 12-months, 92.9% at 2-4 years, and 96.4% at >5 years. During the post-procedural period, mRS remained stable or improved in 96.2% of patients, with stability or improvement in 99.1% of patients >5 years. The overall major morbidity and neurological mortality rate was 5.8%. At multivariate analysis, age (HR 1.04; 95% CI 1.01-1.07, p=0.002) and non-saccular morphology (HR 2.91; 95% CI 1.06-7.97, p=0.038) were identified as independent predictors of mRs worsening. We found a trend towards lower rates of thromboembolic complications since the implementation of prasugrel, with 26 (4.4%) patients on clopidogrel developing stroke compared with 4 (1.6%) patients on prasugrel (OR 2.74; 95% CI 0.95-7.95, p=0.06). Trend towards less thromboembolic complications with PED Shield N= 3/213 (1,4%) OR 0.38 (95% CI o.12; 1.27), p value=0.11

Conclusion:
This study demonstrated high rates of long-term complete aneurysm occlusion, stable or improved functional outcomes, and low rates of complications and mortality. Clinical and angiographic outcomes improved over long-term follow-up, demonstrating endovascular treatment of IA with PED is safe and effective.
Abstract TMP33: Network Analysis Of Acute Stroke Care Systems In Korea
Authors: Kang Jihoon , Bae Hee-joon , Song Hyunjoo , Kim Seong Eun
Published: February 2022

Purpose:
Acute stroke care systems have been shifted to clusters of hospitals for cooperatively applying advanced treatment. It developed various forms of network care systems, of which measurement and evaluation are requested.

Methods:
Using cross-sectional national data for acute stroke care in Korea, hospital usage information after a medical contact was surveyed and transformed into node (hospital) and edge (transfer) format. Of them, dense-linked hospital groups were partitioned as a stroke community using the Louvain algorithm. It investigated the concentration, strength of connection, and functions of derived communities.

Results:
For six months, a total of 19113 subjects with ischemic stroke headed primarily to 1009 hospitals. They merged into 246 ASHs (acute stroke care hospitals) via 3114 (16.3%) secondary interhospital transfers. Those connections were partitioned for the 93 stroke communities (Figure A) comprising median of 9 hospitals (IQR, 5 - 14) and managed a median of 31.3 subjects per month (IQR, 18.2 - 48). They presented highly centralized structure (median group centralization degree [GDC], 1.00), which used to classify the communities (Figure B). One- or two-hospital centered communities showed similar performances of endovascular treatment (EVT) compared to lower volume or poor formatted communities.

Conclusions:
The network analysis method effectively contoured the high centralizing stroke communities and helped the functions on the EVT accessibility.
Abstract TMP35: Prehospital Bypass Policies Increase The Proportion Of Stroke Patients Transported To Primary Stroke Centers - A Quasi-experimental Study In A National Sample Of Medicare Beneficiaries.
Authors: Govindarajan Prasanthi , Meng Tong , Trickey Amber , Matheson Loretta , GILCHRIST SIOBHAN , Rosenthal Sarah , Sox-Harris Alex , Wagner Todd
Published: February 2022

Objective:
Prehospital bypass policies were designed to encourage transport of eligible stroke patients to stroke centers in order to receive rapid assessment and treatment. In a national dataset we examined the relationship between implementation of bypass policies and the proportion of patients transported to stroke centers.

Methods:
We included EMS transported ischemic stroke patients aged 66+ from a 20% sample of Medicare claims (2007 - 2014). We excluded patients not admitted through the ED, and those not continuously enrolled in parts A/B in the prior year. The outcome measure was transport to PSC. Stroke certification status was validated by multiple stroke certification databases; policy implementation details were obtained from review of statutes and regulations. We employed difference-in-differences (DID) analyses with a state-level random intercept.

Results:
A total of 20,345 patients were included in the study with 7,239 from policy states and counties and 13,106 from non-policy states and counties. The proportion of patients arriving at PSCs increased from 28% to 43% in non-policy areas and 33% to 57% in policy areas. The DID analysis revealed a net effect of 11% (p<.001): policy areashad 17% higher probability of transporting stroke patients to PSCs after policy implementation (p<.001) while non-policy areas demonstrated a 6% increase (p<.001). Patients from rural areas had 49% lower odds of transport to PSC (OR 0.51, p<.001).

Discussion:
In pre-thrombectomy era, statewide prehospital bypass policies were related to significant increases in proportion of stroke patients transported to stroke centers. Future analyses will assess if these effects occur in the thrombectomy era, and if these policies influence delivery of stroke treatments.
Abstract TMP36: Improve Patient Outcomes In A Specialized Neurological Emergency Department
Authors: Greenberg Karen J , Bathini Abhijith , Maxwell Christina , BINNING Mandy J , Veznedaroglu Erol
Published: February 2022

Improved Patient Outcomes In A Specialized Neurological Emergency Department

Introduction:
Stroke is now the fifth leading cause of death in the U.S., but remains the leading cause of long term disability. Target: Stroke helps hospitals achieve improved stroke outcomes through reduced door-to-needle times for eligible stroke patients. Phase III of the American Heart Association/American Stroke Association initiative set more aggressive targets for timely treatment with IV alteplase. To achieve rapid treatment times and better patient outcomes, we created a neurologic emergency department (Neuro ED). Neuro ED hours are staffed by emergency physicians with specialized neuroscience training and administer IV alteplase independently, compared to the traditional ED (TED) where emergency providers consult neurology.

Methods:
This is a retrospective observational study from 2019-2021 comparing outcomes of acute ischemic stroke patients who received IV alteplase following implementation of the Neuro ED compared to a TED. The following metrics were calculated for each patient: Door to Needle times (DTN), door to CT times (DTCT), and pre and post National Institute of Health Stroke Scale (NIHSS)

Results:
74 patients were treated in the Neuro ED and 45 patients were treated in the TED. Average DTN times in the Neuro ED were 27 minutes compared to 65 minutes in the TED. Patients treated in the Neuro ED achieved DTN times of 45 min or less 87% of cases, while only 24% of the time in the TED. Patients treated in the Neuro ED achieved DTN times of 30 min or less 65% of cases, with only 4% of cases in the TED. Average DTCT times in the Neuro ED were 8 minutes faster than the TED. No differences in admission NIHSS were found with an average of 8.75, but a significant improvement was found in discharge NIHSS. Average discharge NIHSS was 3.8 for Neuro ED stroke patients compared with 5.6 for TED patients (p<0.001).

Conclusion:
Implementation of a Neuro ED led to swift management and improved symptoms for stroke patients. A dedicated Neuro ED is highly effective in improving DTN times, DTCT times, and overall stroke outcomes.
Abstract TMP37: Regional Changes And Variation In Emergency Department Use Of Neuroimaging During The Mechanical Thrombectomy Era
Authors: Mamer Lauren E , Kocher Keith E , Cranford James A , Scott Phillip A
Published: February 2022

Introduction:
Intracranial vascular imaging was rapidly incorporated into acute ischemic stroke guidelines after positive endovascular trials in 2015. Since then, indications for advanced neuroimaging have broadened as the time window for treatment of large vessel occlusion stroke expanded. Although neuroimaging has been added to national guidelines, there may be considerable lag in incorporating these practices into standard ED care based on regional practice. We sought to analyze regional changes and variation in advanced neuroimaging relevant to stroke.

Methods:
Longitudinal cohort study using adult encounters admitted to the same hospital in the National Emergency Department Sample (NEDS), an AHRQ dataset containing a weighted 20% sample of US ED encounters. Adult encounters from 2013 to 2018 were included in the analysis. CTA and CTP imaging acquired in the ED was determined from Common Procedural Terminology (CPT) codes. Imaging rates per 100k encounters were analyzed by predefined NEDS region (Northeast, Midwest, South, or West) and by year (2013 vs 2018). Descriptive statistics with t-test used for comparison.

Results:
All regions showed a significant increase in rate of CTA use over time (p<0.001) with the Midwest demonstrating the largest percentage change (542%). All regions showed substantial increases in rate of CTP use across the time period with the Northeast having the largest magnitude of increase (5,376%) followed by the Midwest (1,035%). See Table for detail.

Conclusion:
Dramatic increases in CTA and CTP use by region were identified both in absolute terms and relative to their use in 2013. The findings demonstrate approximate geographic parity in order of magnitude of use with the change in usage suggesting rapid dissemination of new technologies in stroke imaging and future potential increases. Further analysis will evaluate other hospital properties to better understand changes in imaging rates nationally.
Abstract TMP45: Potential For Unwarranted Poor Institutional Patient Safety Scores From Inclusion Of Endovascular Thrombectomy In Us National Ahrq Patient Safety Indicator Program
Authors: redier-Demer melissa , Colby Geoffrey
Published: February 2022

Introduction:
The US Agency of Healthcare Research and Quality (AHRQ) has defined 19 Patient Safety Indicators (PSIs) identifying preventable inpatient events. For endovascular and surgical procedures, PSI-4 is applied: detection of mortality after post-procedural complications of pneumonia, DVT/PE, sepsis, GI hemorrhage, or shock/cardiac arrest. But while a potentially useful metric for elective procedures with expected good outcomes, PSI-4 is also appled to emergent endovascular thrombectomy (EVT) for acute ischemic stroke, which has a high rate of unavoidable fatal outcomes. The appropriateness of PSI-4 for EVT assessment has not been empirically studied.

Methods:
1) Systematic literature review to identify comparative rates of unwanted outcomes across all PSIs and diverse endovascular/surgical procedures. 2) Detailed review of consecutive EVT cases at a CSC administratively receiving a PSI-4 safety concern finding by independent non-interventional stroke and neurointerventional experts.

Results:
The systematic literature review found the overall national event frequency for PSI-4 across all endovascular/surgical procedures was one to several orders of magnitude higher than for the other 18 PSIs, 11.9% vs 0.0004% to 2.1%. Further, within PSI-4, the national event rate for EVT was substantially higher than for general endovascular and surgical procedures, 40.1% vs 11.9%. During a 3-year period from 2016-2018 at the CSC, EVT cases accounted for 11% of neurosurgical PSI-4 findings though they represented only 1.5% of neurosurgical procedures. Detailed analysis of 4 consecutive EVT cases coded as PSI-4 safety events from administrative data per AHRQ algorithms revealed that in all cases patient deaths were actually related to complications of the index stroke, not of the EVT procedure - the cases raised no actual safety concerns.

Conclusion:
AHRQ Patient Safety Indicator-4 does not identify preventable events among EVT patients and has the potential to misleadingly suggest poor quality of care at hospitals that provide a high volume of endovascular stroke interventions. To avoid unintended consequences of discouraging institutions from pursuing EVT or incorrectly profiling their safety performance, revision of PSI-4 is indicated.
Abstract TMP47: Food Insecurity And Long Term Mortality Rates After Stroke In The US
Authors: Cross Danielle B , Ovbiagele Bruce , Markovic Daniela , Towfighi Amytis
Published: February 2022

Background:
Around 50 million people in the US have inadequate access to nutritious food. Food insecurity is linked with chronic conditions and worse overall health. Research has shown that living in a lower SES neighborhood is linked to increased post-stroke mortality, but little is known about the effect of food insecurity on mortality.

Methods:
This study used the National Health and Nutrition Examination Survey (NHANES) dataset 1999/2000-2013/2014 with linked mortality files through 2015. Participants included those ≥ 20 years with a complete survey, physical examination, and mortality information. Stroke was self-reported. Food security was characterized as food secure (full, marginal) or food insecure (low, very low). We evaluated the relationship between food insecurity and all-cause, cardiovascular (CV) and stroke mortality in the general and stroke population using Cox proportional hazards regression models, adjusting for sociodemographic factors and comorbidities.

Results:
From 1999 to 2014, 40,777 people participated in NHANES and 1,530 reported a history of stroke. Prevalence of food insecurity was 11.6% in the general population and 15.5% in the stroke subset. Among the general population, there were 5394 deaths due to all-causes, 1152 CV deaths, and 216 stroke deaths. Among the stroke population, there were 650 deaths due to all-causes, 176 CV deaths, and 41 stroke deaths. In the general population, food insecure individuals had higher adjusted all-cause mortality (aHR 1.15, CI 1.01-1.32) and a trend towards higher CV (aHR 1.14, 0.85-1.52) and stroke mortality (aHR 1.23, 0.65-2.34). In participants with prior stroke, food insecurity had no impact on all-cause, CV or stroke mortality.

Discussion:
Although prior studies have demonstrated that living in a low SES neighborhood results in worse post-stroke mortality, this data suggests the effect is not directly linked with food insecurity. A potential explanation is that individuals may receive greater access to food resources after a stroke. There is also the possibility that the low frequency of deaths among stroke survivors limited the ability to detect an effect. Further study is needed to explore the underpinnings of worse post-stroke outcomes in lower SES neighborhoods.
Abstract TMP49: Prevalence Of Acute Respiratory Distress Syndrome In Patients With Aneurysmal Subarachnoid Hemorrhage: A Systematic Review And Meta-analysis
Authors: Fan Tracey , Huang Merry , Price Carrie , Premraj Lavienraj , Kannapadi Nivedha , Suarez Jose , Cho Sung-Min C
Published: February 2022

Objectives:
Acute respiratory distress syndrome (ARDS) is a frequent complication seen in patients after aneurysmal subarachnoid hemorrhage (aSAH), but its prevalence, timing, and influence on neurological outcome is unclear. We aimed to investigate the prevalence, timing, risk factors, and outcome of ARDS in patients with aSAH.

Methods:
PubMed and four other databases (Embase, Cochrane Library, Web of Science Core Collection, and Scopus) from inception to July 6, 2020. We included all randomized controlled trials (RCTs) and observational studies of patients older than 18 years old. Two independent reviewers extracted the data. Study quality was assessed by the Cochrane Risk of Bias tool for RCTs, the Newcastle-Ottawa Scale for cohort and case-control studies. High-grade aSAH was defined as admission Glasgow coma scale 3-5 and/or modified fisher scale>=3 and/or Hunt Hess grade>=3. Good neurological outcome was defined as Glasgow Outcome Scale ≥ 4. Random-effects meta-analyses were conducted to estimate pooled outcome prevalence and their 95% confidence intervals (CI).

Results:
Nine observational studies (n=2,039) met the inclusion criteria, with the median age of 55 years (range=50-61, 28% male) and 71% patients suffered high-grade aSAH. Overall, 16% patients (95% CI=0.05-0.28, I2=94%) had ARDS after aSAH. The median time from SAH to ARDS was 3 days (range=2-6 days). Overall survival at discharge was 79% (95% CI=0.71-0.87; I2=95%) and good neurological outcome at any time was achieved in 65% of aSAH patients (95%CI=0.61-0.69; I2= 0.02%). aSAH cohort without ARDS had higher proportion of survival compared to those with ARDS (79% vs. 49%, p=0.028). Male sex, patients with high-grade aSAH, patients who developed pneumonia and systemic inflammatory response syndrome during hospital admission were at higher risk of developing ARDS.

Conclusions:
In this meta-analysis, approximately one in six patients developed ARDS after aSAH with the median time of 3 days from initial presentation and is associated with increased mortality. Further research to better understand the prevention and treatment strategy is necessary.
Abstract TMP52: Obstructive Sleep Apnea In Acute Ischemic Stroke Patients In The United States: Temporal Trends And Outcomes
Authors: Sharma Richa , Rao Sweta , Jasne Adam , Forman Rachel , Otite Fadar O , Sharma Richa
Published: February 2022

Introduction:
Obstructive sleep apnea (OSA) is a known ischemic stroke risk factor. We analyzed OSA prevalence trends in hospitalized acute ischemic stroke (AIS) patients and treatment utilization and outcomes among AIS patients with and without OSA.

Methods:
Hospitalized adults 18 and over with a primary diagnosis of AIS per ICD-9 and 10 codes recorded in the Nationwide Inpatient Sample from 2005-2017 were identified. The diagnosis of OSA was identified by ICD-9 and 10 codes. National estimates were generated using discharge weights. Temporal trends in OSA prevalence were analyzed by logistic regression. Links between OSA and IV-tPA and endovascular thrombectomy (EVT) use, mechanical ventilation, discharge disposition, and in-hospital mortality were assessed by adjusted logistic regression models.

Results:
Of 5,864,798 AIS patients, 234,339 (4.0%) had OSA (intravenous tPA (n=18,421; 7.9%), EVT (n=3,787; 1.6%), in-hospital deaths (n=10,422; 4.5%)). OSA rates in AIS increased from 0.16% in 2005 to 6.3% in 2017 (p-value < .001). OSA AIS patients were younger (mean age 66 vs. 73 years, p<0.01), male (62.4% vs. 46.8%, p-value; p<0.01), White (73.6% vs. 69.1%, p-value p<0.01), obese (67.1% vs. 32.9%, p-value < 0.01), and had a higher Charlson comorbidity index (mean 3.2 vs. 2.6, p-value < 0.01). Adjusting for demographics and comorbidities, OSA AIS versus non-OSA AIS patients were more likely to be treated with IV- tPA and as likely to receive EVT and mechanical ventilation. Adjusting for demographics, comorbidities, and treatments, OSA AIS patients were less likely to die during hospitalization and more likely to be discharged home.

Conclusion:
Prevalence of OSA among hospitalized AIS patients increased from 2005-2017. OSA AIS patients were treated at a higher rate with IV-tPA and at a similar rate with EVT. OSA AIS patients had better functional outcomes. Further study is needed to understand the mediators of favorable outcomes in AIS patients diagnosed with OSA.
Abstract TMP60: Association Of Blood Pressure Variability With Death And Discharge Destination Among Stroke And Non-stroke Critical Illness Patients
Authors: Stulberg Eric L , Zheutlin Alexander , Harris Benjamin , Delic Alen , Sheibani Nazanin , Anadani Mohammad , yaghi shadi , Petersen Nils H , de Havenon Adam H
Published: February 2022

Introduction:
High blood pressure variability (BPV) is associated with worse prognoses among critically ill stroke and non-stroke patients. It is unclear if higher BPV’s association with worse outcomes is a unique sequela of stroke or a modifiable risk factor among all critically-ill patients.

Methods:
Using data from 7,939 ICU patients hospitalized between 2001 and 2012 in the Medical Information Mart for Intensive Care III (MIMIC-III) database, we examined (1) differences in BPV between stroke and non-stroke patients, (2) BPV’s associations with in-hospital death and favorable discharge destination in stroke and non-stroke patients after adjusting for confounders, and (3) how minimum systolic blood pressure (SBP) - a correlate of illness severity and cerebral perfusion - affected these associations.

Results:
BPV was higher in stroke patients compared to non-stroke patients. In regression analyses, higher BPV was significantly associated with higher odds of in-hospital death and unfavorable discharge amongst stroke and non-stroke patients. After adjusting for minimum tertile of SBP to account for illness severity and cerebral perfusion, higher BPV was significantly associated with higher odds of in-hospital death and lower odds of favorable discharge destination only in patients with ischemic stroke (OR
in-hospital death
2.1, 95% CI: 1.0-4.1; OR
favorable discharge
0.6, 95% CI: 0.4-0.9) or intracerebral hemorrhage (OR
in-hospital death
3.3, 95% CI: 1.8-6.1; OR
unfavorable discharge
0.4, 95% CI: 0.3-0.7).

Conclusion:
Among critically ill stroke patients, BPV seems to represent both generalized critical illness as well as a specific feature of stroke. BPV in critically ill stroke patients may be in part a function of injury to the central autonomic network or modulation of sympathetic outflow.
Abstract TMP61: Telerobotic Neurovascular Interventions With Magnetic Manipulation
Authors: Kim Yoonho , Genevriere Emily , Harker Pablo , Balicki Marcin , Lee Sang U , Bowman Heather G , Patel Aman B , Zhao Xuanhe
Published: February 2022

Background:
Advances in robotic technology have been adopted in various subspecialties of both open and minimally invasive surgery, offering benefits such as enhanced surgical precision and accuracy with reduced efforts and fatigue. Despite the advantages, robotic applications to endovascular neurosurgery have remained largely unexplored due to technical challenges such as the miniaturization of robotic devices that can navigate the complex and tortuous cerebral vasculature. Although some commercial robotic systems enable precise manipulation of conventional guidewires for coronary and peripheral vascular interventions, they remain unsuited for neurovascular applications due to the considerably smaller and more tortuous anatomy of cerebral arteries.

Methods:
We present a teleoperated robotic system designed for neurovascular interventions based on magnetic steering and navigation. Our system consists of a magnetically controlled guidewire, a robot arm with a permanent magnet attached to its end-effector for steering control of the guidewire, a set of motorized linear drives to advance or retract the guidewire and a microcatheter, and a remote-control console to operate the system under feedback from real-time fluoroscopic imaging and visualization.

Results:
With a life-sized neurovascular phantom, we demonstrate the navigational capability to reach several branches of circle of Willis and distal cerebral vasculature with the magnetic guidewire under teleoperation of the system. We further demonstrate telerobotically-assisted therapeutic procedures including coil embolization and clot retrieval thrombectomy for intracranial aneurysms and ischemic stroke, respectively.

Conclusion:
Our telerobotic neurointerventional platform could enable safer and quicker access to hard-to-reach lesions, significantly reduce operative time and perioperative risk by reducing intravascular manipulation, minimize the radiation exposure to interventionalists, and open the possibility of remote procedural services to address challenges in current stroke systems of care.

Note:
Animal testing will be performed in Q3 2021 and the results will be presented at ISC.
Abstract TMP66: A Prognostic Scoring System Of Mechanical Thrombectomy For Elderly Patients
Authors: Arimura Koichi , Miki Kenji , Nishimura Ataru , Matsuo Ryu , Koyanagi Yuya , Okuda Tomohiro , Iwaki Katsuma , IDO KEISUKE , Tokunaga So , Yoshida Hidenori , Yoshimoto Koji
Published: February 2022

Background and Purpose:
Japan has a rapidly aging population and the application of mechanical thrombectomy (MT) for acute ischemic stroke (AIS) among elderly patients has increased, but feasibility and safety of MT for elderly patients are still debated. Therefore, this study aimed to elucidate feasibility and safety of MT by analyzing the retrospective multicenter database.

Methods:
A total of 763 consecutive patients who underwent MT for AIS between January 2013 and January 2020 at six comprehensive stroke centers were enrolled in this study. We analyzed elderly AIS patients defined as those aged ≥ 75 years with IC/M1/M2 occlusion. Good outcome was defined mRS 0-2 at 90 days after onset, and we investigated the factors associated with good outcome.

Results:
A total of 523 patients with IC/M1/M2 occlusion were analyzed, of which 316 were elderly (52%). Good outcome was significantly decreased in elderly AIS patients compared with non-elderly patients (35 % vs 56 %, p=0.0007). Among the elderly AIS patients, aged < 90 years, male sex, NIH stroke scale, prior administration of anticoagulants, mRS before onset, ASPECTS, M2 occlusion, and dyslipidemia were associated with good outcome with multivariable analysis. An elderly AIS prognostic scoring system (eAIS-PSS) was set up based on these factors , and the areas under the curves (AUC) was 0.78 at the optimal cut-off value of 7 / 22 with this scoring system. eAIS-PSS predicted good outcome with a sensitivity of 72% and a specificity of 75%.

Conclusion:
eAIS-PSS was useful to predict good outcome in MT for elderly AIS patients.
Abstract TMP67: Predictors Of Unfavourable Events Despite Successful Mechanical Thrombectomy In The Extended Window
Authors: Seker Fatih , Qureshi Muhammad M , Möhlenbruch Markus , Nogueira Raul G , AbdalKader Mohamad , Ribo Marc , Caparros Francois , Mohammaden Mahmoud , Haussen Diogo C , Sheth Sunil A , Ortega-Gutiérrez Santiago , Siegler James E , Zaidi Syed F , Olive-Gadea Marta , Henon Hilde , Castonguay Alicia , Nannoni Stefania , Kaesmacher Johannes , Puri Ajit S , Farooqui Mudassir , Salazar-Marioni Sergio , Kuhn Anna Luisa , Kiley Nicole , Farzin Behzad , Boisseau William , Masoud Hesham E , Lopez Carlos , Rana Ameena , Abdul Kareem Samer A , Sathya Anvitha , Klein Piers , Kassem Mohammad W , Cordonnier Charlotte , Gralla Jan , Fischer Urs M , Michel Patrik , Jovin Tudor G , Raymond Jean , Zaidat Osama , Ringleb Peter A , Nguyen Thanh N , Nagel Simon
Published: February 2022

Background:
Futile recanalization (FR) and symptomatic intracranial hemorrhage (sICH) are adverse outcomes after otherwise successful mechanical thrombectomy (MT). The aim of this study was to evaluate independent predictors of these unfavourable events in the extended time window and to compare imaging modalities (non-enhanced CT (NCCT) alone vs. CT perfusion vs. MRI) regarding patient selection.

Methods:
The CT for Late EndovasculAr Reperfusion (CLEAR) study was a multicenter, retrospective study of stroke patients undergoing thrombectomy in the extended time window. The primary endpoint of this study was the proportion of patients with FR, defined as a patient with large vessel occlusion achieving near-complete or complete reperfusion (TICI 2c/3) with a 90-day mRS score between 3 and 6. The secondary safety endpoints included the predictors of mortality and symptomatic intracranial hemorrhage. Inclusion criteria for this analysis were baseline NIHSS ≥6, internal carotid artery, M1 or M2 segment occlusion, prestroke modified rankin scale (pmRS) 0-2, time last seen well (TLSW) to treatment 6-24 hours, and mTICI 2c-3.

Results:
Of 2304 patients in the CLEAR study, 715 patients were included in this analysis. Of these, 364 patients (50.9%) showed FR, 37 patients (5.2%) suffered sICH and 127 patients (17.8%) died within 90 days. Old age, higher baseline NIHSS, higher prestroke disability, transfer to a comprehensive stroke center from another site, and a longer interval from TLSW to puncture were identified as positive predictors of FR. Hypertension was an independent predictor of sICH. The imaging modality (NCCT vs. CT perfusion vs. MRI) was not associated with FR, sICH, or mortality.

Conclusions:
Older age, higher baseline NIHSS, higher prestroke disability, transfer patients, and a longer interval from TLSW to puncture were predictors of FR in the extended window. Hypertension was a predictor of sICH in successfully reperfused patients. Neither MRI or CT perfusion was superior in predicting FR and sICH compared to NCCT alone. NCCT together with CTA may be sufficient for patient selection in the extended time window.

Trial Registration:
ClinicalTrials.gov
Identifier: NCT04096248
Abstract TMP72: Comparison Of Transradial Artery Versus Transfemoral Artery Access Mechanical Thrombectomy At A Comprehensive Stroke Center
Authors: Nisar Taha , Patel Jimmy , Singla Amit , Khandelwal Priyank
Published: February 2022

Introduction:
The transradial approach (TRA) is being increasingly adopted by neuro-interventionists and has emerged as an alternative to the traditional transfemoral approach (TFA) for mechanical thrombectomy (MT). We aim to compare various time, technical and outcome parameters in patients who undergo MT via TRF vs. TRA approach.

Methods:
We performed a retrospective chart review of patients who underwent MT at a comprehensive stroke center from 7/2014 to 12/2020. We compared patients who underwent MT via TRA vs. TRF with respect to time from angio suite arrival to puncture, first pass, second pass and recanalization; time from puncture to first pass, second pass and recanalization; time from arrival to the emergency department (ED) to puncture, first pass, second pass and recanalization; the number of passes, rate of switching, achievement of TICI≥2b score, functional independence (3-month mRS≤2), 3-month mortality and neurological improvement (improvement in NIHSS by ≥4 points) on day 1 and 3. A binary logistic regression analysis was performed, controlling for age, sex, NIHSS, type of anesthesia (general vs. moderate), laterality, and location of clot (internal carotid or middle cerebral artery), ASPECTS≥6, presenting mean arterial pressure, blood glucose, Hb A1C, LDL, intravenous alteplase.

Results:
217 patients met our inclusion criteria. The mean age was 64.09±14.4 years. 42 (19.35%) patients underwent MT through the TRA approach. There was a significantly higher rate of conversion from TRA approach to TRF approach (11.90% vs.2.28%; OR, 105.59; 95% CI,5.71-1954.67; P 0.002), but no difference in various time, technical and outcome parameters, as shown in the table.

Conclusions:
Our study demonstrates no significant difference between TRA and TRF approaches with respect to various time, technical and outcome parameters, with a notable exception of a significantly higher rate of conversion from TRA to TRF approach.
Abstract TMP73: Patterns Of Index And Recurrent Stroke In Patients With Intracranial Stenosis
Authors: Nankee Cassie L , Turan Tanya N , Chimowitz Marc , Wabnitz Ashley M , Cotsonis George A , Derdeyn Colin P , Fiorella David
Published: February 2022

Background and Purpose:
Pattern of infarct due to ICAS (e.g. borderzone) may predict recurrent stroke risk. We sought to describe the patterns of index and recurrent infarcts in patients enrolled in the medical arm of the SAMMPRIS Trial (Stenting and Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis).

Methods:
- Patients enrolled in the medical management arm of the SAMMPRIS trial with infarct as the qualifying event who had CT or MRI, or those with a recurrent infarct in the territory of the symptomatic artery during follow up were included. Infarct pattern for both the index infarct and any recurrent infarct in the territory was determined using criteria defined in prior SAMMPRIS publications as borderzone, MCA artery core, and perforator for anterior circulation and cerebellar, perforator and distal for posterior circulation (see figure for examples). Infarct pattern was adjudicated independently by 2 reviewers, with a 3
rd
reviewer as tiebreaker.

Results:
- Among the 142 patients who had index infarcts in the anterior circulation (n=101) and posterior (n=41) circulation, the patterns were: 53 (37.3%) borderzone, 24 (16.9%) MCA core, 35 (24.6%) perforator, 13 (9.2%) distal, and 17 (12%) cerebellar. Among the 31 who had recurrent infarct in the territory, the patterns were: 10 (32.3%) borderzone, 6 (19.4%) MCA core, 6 (19.4%) perforator, 4 (12.9%) distal, 1 (3.2%) cerebellar, and 4 (12.9%) were missing imaging. Of the recurrent infarcts in territory, 21 had both index infarct and recurrent infarct in territory adjudications, with 11 demonstrating the same pattern of infarct for both events (7 borderzone, 2 core, 2 perforator).

Conclusions:
- The majority of patients with stroke due to severe symptomatic intracranial stenosis demonstrated borderzone pattern of infarct for index and recurrent infarcts. Ongoing analyses of this dataset will determine the association between pattern of index stroke and risk of recurrent stroke.
Abstract TMP76: Association Of Adiposity With Intracranial Atherosclerosis
Authors: Logue Makenzie , Sen Souvik , Suri Fareed , Wasserman Bruce , Gottesman Rebecca F , Rosamond Wayne D
Published: February 2022

Introduction:
Adiposity, as measured by Body Mass Index (BMI) and Waist-to-Hip Ratio (WHR), is associated with ischemic stroke. However, association with Intercranial Atherosclerosis has not been well-established in the United States. We assessed the hypothesis that adiposity is associated with asymptomatic intracranial atherosclerosis (ICAS).

Methods:
BMI was calculated as weight (kg)/height (m)
2
. The ratio of waist (umbilical level) to hip (maximum buttocks) circumference (WHR) was calculated as a measure of fat distribution. In the ARIC cohort, a stratified subset (N=1145) underwent 3D time-of-flight MR angiogram and 3D high-isotropic resolution black blood MRI. ICAS was graded according to the criteria established by the Warfarin-Aspirin Symptomatic Intracranial Disease trial. In this study, we evaluated the relationship between BMI as well as WHR, and significant asymptomatic ICAS, defined as ≥50% stenosis. Student t-tests were performed to test continuous variables, and X
2
test was used to compare categorical variables. Analysis of covariance (ANCOVA) was used for multivariate testing.

Results:
Among subjects who underwent vascular imaging, 1033 (90%) had <50% ICAS and 112 (10%) had ≥50% ICAS. At the time of assessment, those with ≥50% ICAS were older (age 79±5 vs. 76±5, p<0.001), and had higher systolic blood pressure or SBP (134±19 vs. 130±18, p=0.02), compared with those with <50% ICAS. The BMI was higher (29.1±6.7 vs. 28.1±5.2), although the difference was statistically borderline significant (p=0.06). The WHR was higher (0.95±0.07 vs. 0.93±0,08), the difference being statistically significant (p=0.01). The difference remained significant after adjustment for age and SBP (p=0.02).

Conclusion:
We report a significant association between WHR, a measure of central adiposity, and ≥50% ICAS. This may be one of the first reported associations between central adiposity and ICAS. These results emphasize the importance of adiposity distribution in addition to overall adiposity, as a risk factor for significant asymptomatic ICAS.
Abstract TMP78: Relationship Of
RNF213
p.R4810k Variant And Familial Hypercholesterolemia To Intracranial Major Arterial Stenosis/occlusion
Authors: Noda Kotaro , Hattori Yorito , Hori Mika , Tanaka Akito , Harada-shiba Mariko , Ihara Masafumi
Published: February 2022

Introduction:
The ring finger protein 213 gene (
RNF213
) p.R4810K variant is a susceptibility gene for Moyamoya disease in East Asians. Besides, the variant is also strong genetic risk factor for ischemic stroke due to intracranial major arterial stenosis/occlusion (ICASO) responsible for anterior circulation, and 2–3% of East Asians also harbor the variant as asymptomatic carriers. Therefore, it is suggested that several additional factors should be required to develop ICASO in the patients with the variant. Familial hypercholesterolemia (FH) is the most common genetic disorder in Japan, caused by
LDLR
,
PCSK9
, and/or
APOB
gene mutations. FH is a great risk factor for coronary atherosclerosis, but the relationship between FH and ICASO is still unknown. We aimed to investigate whether
RNF213
p.R4810K affects the prevalence of ICASO in FH patients.

Methods:
We enrolled the patients who were diagnosed as FH and underwent brain MRI at our hospital from May 2005 to June 2021. We examined
RNF213
p. R4810K variant, and
LDLR
and
PCSK9
gene mutations, and analyzed the existence of ICASO in the brain MRA.

Results:
A hundred and sixty-seven patients with FH (
LDLR
, n=104;
PCSK9
, n=22) underwent MRI. The average age at MRI testing was 61, and 46.1% were male. Six patients harbored
RNF213
p. R4810K (3.59%) without past history of stroke. ICASO in anterior circulation was observed in 5 with the variant (85%), and there was a significant difference in the existence of ICASO between the patients with the variant and those without it (OR 9.12, 95% CI 1.38-18.7, p=0.027). The number of arteries with stenotic lesions in anterior circulation was significantly larger in the patients with the variant than those without the variant (3.33 vs. 0.68:p=0.01).
LDLR
and/or
PCSK9
gene mutations similarly induced ICASO in the FH patients.

Discussion:
Our study revealed that
RNF213
p. R4810K was associated with ICASO in the patients with FH. The incidence of ICASO in normal volunteers has been reported to be around 10%, suggesting that FH may raise the occurrence of ICASO associated with
RNF213
p.R4810K. The combination of gene mutations responsible for FH and
RNF213
p. R4810K variant would confer the greater risk of ICASO in anterior circulation.