bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract TMP16: Morphologic Evolution and Remodelling of Intracranial Atherosclerosis Under Intensive Risk Factor Control
Authors: Leung Thomas , Soo Yannie , Ip Vincent , Wong Ka Sing , Yu Simon
Published: July 2021

Introduction:
In SAMMPRIS, the benefit of aggressive medical therapy over stenting persisted throughout the extended follow-up. It is uncertain how modern medical management could diminish stroke relapses.

Method:
In a prospective academic-initiated study, we recruited 40 patients (mean age 63.4±9.0 years) with acute strokes attributed to high-grade (≥70%) intracranial atherosclerotic stenosis for 3D-rotational angiograms before and after intensive medical therapy for 12 months. Treatment targets included low-density lipoprotein <70 mg/dl; HbA1c <6.5%; and systolic blood pressure <140 mmHg. We analyzed the morphologic and geometric evolution of the symptomatic plaques.

Results:
Overall, the risk factor control reached the pre-specified intensity. Plaque thickness, and hence luminal narrowing, significantly diminished at one year (from 1.50±0.48 to 1.24±0.42mm; p<0.001). The site of maximal stenosis shifted significantly towards mid-portion of the plaque (p<0.001), leading to a diminished upstream angulation. The ulcers noted at baseline (n=3) had all healed by one year. There was no significant change in terms of plaque length or lesion eccentricity.

Conclusion:
Intracranial plaques might regress and positively remodel under intensive risk factor control. These morphologic changes might stabilise the plaques, alleviate unfavourable hemodynamics across the steno-occlusion, and hence reduce the risk of plaque rupture or platelet aggregation.
Abstract TMP19: Carotid Endarterectomy in Patients With Thrombocytopenia. Analysis of National Surgical Quality Improvement Program (NSQIP) Registry
Authors: Zafar Aiman , Jani Vishal B , Miran Muhammad Shah , Yousaf Muhammad H , Patel Urvish , Qureshi Adnan I
Published: July 2021

Background:
Carotid revascularization procedures are infrequently performed in patients with mild-moderate thrombocytopenia. However, whether such procedures are associated with a higher unknown risk of peri-procedural complications such as myocardial infarction (MI)/arrhythmia, need for blood transfusions, unplanned intubations, and death. There is no large population based study available to quantify the risk after carotid endarterectomy (CEA) in patients with thrombocytopenia.

Methods:
We studied all patients who underwent CEA in the American College of Surgeons (ACS) National Surgical Quality Improvement Program(NSQIP) Registry between years 2011 and 2013.The ACS-NSQIP prospectively collects data on over 300 variables pertaining to patient characteristics, comorbid conditions, operative details, and 30-day post-operative outcomes. Thrombocytopenia was defined based on the pre procedure platelet count of <150,000 platelet/μL. The odds ratios for selected outcomes were calculated after adjusting for age, gender, and symptomatic status using logistic regression.

Results:
Thrombocytopenia was present in 931(10.5%) of 8835 patients who underwent CEA. Their severity of thrombocytopenia was mild (100,000-149,000 platelets/μL) and moderate (<100,000platelets/μL) in 821(88.18%) and 110(11.8%) patients, respectively. Patients with thrombocytopenia were more likely to be asymptomatic prior to CEA (54.4% vs. 45.6%; p=0.02). There was a significantly higher prevalence of MI/arrhythmia among patients with thrombocytopenia in compare to without (3.7% vs. 1.8%; odds ratio [OR]: 1.95; 95% confidence interval [CI]: 1.33-2.88; p<0.001). The incidence of unplanned intubation post CEA was higher among patients with thrombocytopenia (2.5% vs. 1.2%; p=0.004). There were no differences in the need for blood transfusions (2.5% vs. 2.4%; OR: 1.05; 95% CI: 0.67-1.64; p =0.83) and one month mortality (0.6% vs. 0.8%; OR: 0.66; 95% CI: 0.28-1.54; p=0.33) among patients with and without thrombocytopenia.

Conclusions:
The higher rate of post procedural complications in patients with thrombocytopenia needs to be recognized for appropriate risk stratification.
Abstract TMP30: SICI During Voluntary Movement Reveals Persistent Impairment in Cortical Stroke
Authors: Patten Carolynn , Ding Qian , Kamath Manjeshwar Sahana S , Triggs William J
Published: July 2021

Introduction:
Short intracortical inhibition (SICI) is a GABAa-mediated phenomenon argued to mediate motor selectivity. SICI is markedly reduced, producing motor disinhibition, in the sub-acute period following cortical (CORT), but not subcortical (SC), stroke. Previous work suggests SICI may normalize as part of the natural course of recovery. Importantly, SICI is typically measured at rest complicating our understanding of its role in motor control and recovery following stroke. Here we investigated task-dependent differences in SICI in chronic stroke survivors.

Hypothesis:
We hypothesized: i) differences between SICI measured at rest and during voluntary movement and ii) SICI during voluntary movement would reveal persistent impairments following CORT stroke.

Methods:
We tested 13 adults (65±8.5 yr, 11 male) with chronic (72.8±52.6 mo) stroke (5 CORT, 8 SC) and 7 controls (CON)(58±6.9 yr, 4 male) using paired-pulse transcranial magnetic stimulation during 3 tasks: rest, grip, box & blocks (B&B). Motor evoked responses (MEPs) were measured from the first dorsal interosseous of the paretic and non-dominant hands of stroke and CON, respectively. SICI was induced by conditioning the test MEP at 0.8 resting or 0.7 active, motor threshold at the interstimulus interval producing maximal SICI at R (3 ms CON, 3.7 ms Stroke) and quantified as the ratio of conditioned/unconditioned MEParea. Stimulation intensity was adjusted to maintain test MEP amplitude at 1mV pk-pk across tasks.

Results:
At rest, SICI was similar between groups (p > 0.5). However during grip, CORT revealed significantly less SICI than CON or SC (p’s .05). During B&B, CORT again revealed less SICI than CON (p =.04); however SICI was similar between CORT and SC (p >.05). Across tasks, SICI produced by CON and SC was similar (p >.05) while CORT revealed less SICI during both grip and B&B (p’s <.005) compared to rest.

Conclusions:
Measured at rest, SICI is similar across groups suggesting GABAa circuits are normalized as part of the natural course of stroke recovery. However, SICI measured during voluntary motor tasks reveals persistent impairments, which are more widespread following CORT stroke and may interfere with rehabilitation involving voluntary movement.
Abstract TMP78: Tick Tock we Don't Stop - 24/7 Stroke Nurse Clinician Response Improves Care in the Stroke Patient
Authors: Zimmermann Mary
Published: July 2021

Background:
Large community hospitals often face multiple challenges in the emergent care of acute stroke patients. Some of these challenges include decreasing door to IV tPA (activase) time and consistently meeting core measures. The 24/7 utilization of specialized nurses (Stroke Clinicians) trained to respond to acute stroke patients in the ED and inpatient areas improves the outcomes for stroke patients. Utilizing the Stroke Clinician role for 24/7 response to all acute strokes improves each patient’s ability to access complex stroke treatment.

Purpose:
The purpose of implementing 24/7 Stroke Clinician coverage for the ED and all inpatient units was to reduce door to needle times for patients receiving tpa, to increase stroke core measure compliance, and to improve patient outcomes. In addition to responding to acute strokes, the Stroke Clinicians also provide concurrent chart review and patient education.

Methods
The role of the Stroke Clinician was expanded to provide acute stroke response coverage on a continual, 24/7 basis in the first quarter of 2015. Stroke Program administration discussed options for the expanded coverage and subsequently trained the Cardiovascular Clinicians to cover stroke call from 11pm to 7am. These clinicians were already in-house, thus no additional cost was associated with the coverage.

Results:
The door to needle times have consistently decreased from an average of 70 minutes to an average of 50 minutes. There has been a steady improvement in patient outcomes evidenced by doubling the number of stroke patients who have received endovascular therapy since the prior year.

Conclusion:
The implementation of 24 hours per day/7 days per week stroke clinician coverage improved IV tPA door to needle times, improved the utilization of endovascular stroke treatment, and improved compliance with the stroke core measures.
Abstract TP108: Blood Occludin Level Indicates the Extent of Early Blood Brain Barrier Damage in Ischemic Stroke
Authors: Pan Rong , Yu Kewei , Weatherwax1 Theodore , Zheng Handong , Yang Yirong , Liu Wenlan , Liu Ke Jian
Published: July 2021

Background and Purpose:
Fear of symptomatic intracerebral hemorrhage (ICH) has been the primary reason for withholding tPA thrombolysis from acute ischemic stroke patients. Early blood brain barrier (BBB) damage is appreciated to be closely associated with post-thrombolysis ICH, while it remains a technical challenge for rapid assessment of BBB damage before tPA administration. Our recent data showed that cerebral ischemia induced rapid degradation of tight junction protein occludin in ischemic cerebromicrovessels. This study further investigates whether the cleaved occludin is released into the blood stream and how blood occludin levels correlate to the extent of ischemic BBB damage.

Methods:
Male Sprague Dawley rats were subjected to 1.5, 3, 4.5, 12 and 24 hours of middle cerebral artery occlusion (MCAO), followed by 5-min reperfusion. Blood samples were taken before and after MCAO. Blood occludin was assessed by ELISA. BBB permeability was measured by Evans blue dye leakage. Occludin cleavage was identified on immunoblots.

Results:
MCAO induced Evans blue dye leakage and blood occludin increase in a duration-dependent manner. Blood occludin increase concurrently occurred with the loss of occludin from ischemic cerebral microvessels. Western blot analysis identified two cleaved occludin fragments (31- and 55- kDa) in the blood. Lastly, blood occludin levels remained significantly higher than its basal level within the first 24 hours after MCAO onset.

Conclusions:
Our results indicate that blood occludin levels correlate well with the extents of BBB damage and thus may serve as a potential biomarker for evaluating the risk of hemorrhagic transformation before tPA administration.
Abstract TP111: Haptoglobin Improves Intracerebral Hemorrhage Outcomes by Modulating Angiogenic Responses
Authors: Leclerc Jenna , Esfandiary Tina , Dore Sylvain
Published: July 2021

Intracerebral hemorrhage (ICH) most often occurs spontaneously and is one of the most devastating stroke subtypes. Following ICH, toxic blood components must be cleared from the brain as part of the tissue repair/scar formation healing process. Angiogenesis is a key physiologic mechanism that facilitates tissue repair following acute injury, but must be tightly regulated to prevent excessive activity and deleterious consequences. After ICH, regulation of angiogenesis within the appropriate range in injured brain regions would allow for delivery of glucose and oxygen to support the energy-requiring reparative processes and facilitate the necessary entry of peripheral cells involved. Haptoglobin (Hp) is an acute phase protein that binds extracorpuscular hemoglobin, thereby directly reducing its oxidative potential, and Hp has also been shown to have potent angiogenic, vasculogenic, and wound healing properties. Using the autologous blood model of ICH, we have shown that Hp overexpression significantly improves ICH outcomes and reduces oxidative processes. Here, we aimed to confirm our previous results and further characterize the mechanisms by which Hp exerts these neuroprotective effects. Hp was overexpressed in the brain using adeno-associated viral vectors and ICH was induced using the collagenase-induced spontaneous bleeding model, which is accompanied by clinically relevant intraventricular hemorrhage. In line with our previous study, Hp-overexpressing mice demonstrate significantly smaller lesion volumes (p<0.01) and less residual blood (p<0.05). This reduced ICH-induced brain injury is accompanied by trends towards improved ambulatory ability and less focal neurological deficits at 72h post-ICH (p<0.07). Hp-overexpressing mice have significantly reduced PECAM-1 expression and tend to have less VEGF immunoreactivity. After correcting for lesion volume, Hp-overexpressing mice retain the decreased PECAM-1 expression, but VEGF expression is increased, collectively suggesting a direct role of Hp in positively modulating angiogenesis after ICH. Hp therapy could represent a new treatment strategy for ICH through a multifactorial mechanism that includes the modulation of important angiogenic processes.
Abstract TP12: Safety of Endovascular Intervention for Acute Stroke in Patients on Anticoagulation
Authors: Kurowski Donna , Jonczak Karin , Shah Qaisar , Yaghi Shadi , Marshall Randolph S , Ahmad Haroon , McKinney James , Cucchiara Brett L
Published: July 2021

Background and Purpose:
Current guidelines recommend against IV tPA use in patients on warfarin with INR > 1.7, recent use of novel oral anticoagulants (NOACs), or current therapeutic parenteral anticoagulation. These patients are sometimes considered for endovascular thrombolysis, however there is limited data on the safety of this approach. We sought to assess the safety of endovascular intervention in these patients.

Methods:
We performed a multicenter retrospective study to identify consecutive patients undergoing endovascular intervention for acute ischemic stroke while on therapeutic anticoagulation (defined as warfarin use with INR > 1.7, heparin with elevated PTT, or recent LMWH or NOAC use). The primary outcome measure was symptomatic ICH (sICH) using the NINDS definition. We compared the observed rate of sICH to risk-adjusted published historical control rates of sICH after IV tPA using weighted averages of the Hemorrhage after Thrombolysis (HAT) and Multicenter Stroke Survey (MSS) prediction scores.

Results:
Of 82 cases, mean age was 73 ± 15 years, 46% were female, and median NIHSS was 19 (IQR 14-22). Anticoagulation consisted of warfarin (n=43, mean INR 2.3), IV heparin (n=19), NOACs (n=17), and LMWH (n=3). Any ICH on follow-up CT was present in 26 (32%) patients, and sICH in 7 (8.5%, 95% CI 4.2-16.6) patients. All 7 sICH occurred in patients on warfarin. Severe systemic bleeding occurred in 1 patient. At discharge, 10% subjects returned home, 44% went to an acute rehabilitation facility, 27% to a nursing facility, and 19% had died. Predicted sICH rate for the cohort based on HAT and MSS scoring was 12% and 7% respectively.

Conclusions:
Endovascular intervention in subjects on therapeutic anticoagulation appears reasonably safe, with a sICH rate similar to patients not on anticoagulation receiving IV tPA.
Abstract TP124: Tapered Stent Geometry Provides Strong Hemodynamic Effect After Carotid Stenting
Authors: De Rango Paola , Cacioppa Laura , Cieri Enrico , Isernia Giacomo , Simonte Gioele , Lenti Massimo , Farchioni Luca , Verzini Fabio
Published: July 2021

Objective:
In the last years, development of materials allowed notably improvements in interventional approach to stroke. Tapered stents were specifically designed for extracranial carotid stenting (CAS) to deal with vessels mismatch decreasing the risk of thrombosis. Nevertheless, as to whether the stent geometry may affect the hemodynamic consequences of CAS remains uncertain. This study aims to investigate the impact of stent configuration on postprocedural sustained hemodynamic depression (HD) requiring action of care after carotid stenting (CAS).

Methods:
Data on 391 consecutive CAS performed over a 4-year period (2011-2014) were reviewed. Postprocedural sustained HD was defined as any severe hypotension (<90mmHg) or bradicardia (<50beats/min) persisting at >2 measurements after the end of the procedure and requiring care support or delaying hospital discharge. Stent configuration (tapered or straight) was tested for association with sustained HD using multivariable models adjusted for other confounders (medical therapy, comorbidities, symptoms, stenosis, carotid plaque and demographics).The relation with stroke and death outcomes within 30 days of treatment was also analyzed.

Results:
Mean age of patients was 70.7y + 7.14 and 66.2% were males. Sustained HD developed after 144 (36.8%) CAS. Tapered stents were applied in 289 (73.9%) CAS, and more frequently in patients with higher degree of stenosis (mean 79% vs 77%, in tapered and straight stents respectively; P=0.007) or asymptomatic (93.8% vs. 85.3% in tapered and straight stents respectively;P=0.012). Diabetes (HR 1.6, 95% CI, 1.01-2.44;P=0.044) and tapered stent configuration (HR, 1.7, 95% CI, 1.05-2.82;P=0.033) were the only factors that showed independent association with sustained HD. At 30-day, 3 strokes and no death occurred. There was no statistically significant association between 30-day outcomes and sustained HD depression or stent configuration.

Conclusions:
A strong hemodynamic effect, requiring additional actions of care or prolonged hospital stay, is expected after CAS when using tapered stent configuration. These findings alert on the overall benefit and costs of CAS and the requirements for accurate material selection especially in diabetic patients.
Abstract TP134: Genome Wide Association Studies in Han Chinese Populations Identify Novel Susceptibility Loci for Specific Ischemic Stroke Subtypes
Authors: Ko Tai-Ming , Lee Tsong-Hai Lee , Chen Chien-Hsiun , Chen Yuan-Tsong , Wu Jer-Yuarn
Published: July 2021

Introduction:
Although family history studies in ischemic stroke support that genetic factors may be involved in the pathogenesis of two major subtypes of ischemia stroke: large-artery atherosclerosis (LAA) and small-vessel occlusion (SVO), it is still unclear which particular genetic factors contribute to LAA or SVO.

Hypothesis:
Because the etiology of ischemic stroke is heterogeneous, we hypothesize that genetic factors may vary by etiologic subtypes or ethnicities. Thus, we aim to identify genetic factors that contribute to LAA or SVO based on two independent Han Chinese populations.

Methods:
Novel genetic variants that predispose individuals to LAA and SVO were identified by genome-wide association study comprising of 824 individuals (including 444 LAA cases and 380 SVO cases) and 1,727 controls in a Han Chinese population residing in Taiwan. The LAA study was replicated in an independent Han Chinese population comprising of an additional 319 LAA cases and 1,802 controls.

Results:
In LAA cases, from two independent populations, we identified five single-nucleotide polymorphisms (SNPs), including SNP-1 (P = 3.10 х 10–8), SNP-2 (P = 4.00 х 10–9), SNP-3 (P = 3.57 х 10–8), SNP-4 (P = 1.76 х 10–8), and SNP-5 (P = 2.92 х 10–8), at one novel locus on chromosome 14q13.3 within PTCSC3 (encoding papillary thyroid carcinoma susceptibility candidate 3). In SVO cases, from the discovery stage, we identified two novel candidate susceptibility loci on chromosome 3p25.3 (SNP-6, P = 3.24 х 10–5) and chromosome 14 q31.1 (SNP-7, P = 2.58 х 10–4).

Conclusions:
For LAA, the newly identified SNPs within PTCSC3 gene were found to have genome-wide statistical significance (P < 5 х 10–8) and were shown to be located in a risk locus correlated with papillary thyroid carcinoma. Moreover, the genetic association between PTCSC3 gene and SVO was not identified, which suggested that PTCSC3 is a specific susceptibility locus for LAA. For SVO, we identified two novel candidate genetic loci which were valuable for replication by an independent population with SVO. In conclusion, our findings provide insights into the genetic basis of LAA and SVO, which may be applicable in the study of the pathogenesis of ischemic stroke and in the development of alternative therapeutic interventions.
Abstract TP146: Impaired Glucose Metabolism is Associated With Metabolic Inflexibility During Submaximal Exercise in Chronic Stroke Survivors
Authors: Serra Monica C , Hafer-Macko Charlene E , Ivey Frederick M , Ryan Alice S
Published: July 2021

We have previously shown that 27% and 45% of chronic stroke survivors have impaired fasting glucose (IFG) and impaired glucose tolerance (IGT), respectively, placing them at high risk for the development of type 2 diabetes (T2DM). These glucose abnormalities may contribute to metabolic inflexibility, which is the failure to appropriately adapt substrate oxidation to substrate availability. Thus, we tested the hypothesis that the ability to shift from fat (respiratory exchange ratio (RER)=0.7) to carbohydrate (RER=1.0) oxidation during exercise is reduced in stroke survivors with increasing fasting (G0) and 2-hr oral glucose tolerance test (G120) glucose levels. Chronic hemiparetic stroke patients without T2DM (N=18; 63±2 year old; mean±SEM) underwent a graded exercise stress test, with indirect calorimetry for measurement of peak fitness (VO
2
peak). Additionally, we measured RER at rest and during submaximal exercise (60% of VO
2
peak), and subjects completed an OGTT for measurement of G0 and G120. On average, subjects were obese (BMI: 30±2 kg/m
2
; 19-45 ml/kg/min) and had poor VO
2
peak levels (20±1 ml/kg/min; 9-33 ml/kg/min). Thirty three percent had neither IFG nor IGT, while 33% had IFG (G0: 5.22±0.19 mmol/L), 56% had IGT (G120: 7.94±0.49 mmol/L), and 22% had both IFG and IGT. At rest, RER was 0.71±0.01 and increased to 0.78±0.01 at 60% of VO
2
peak (P<0.01). After controlling for obesity and VO
2
peak, G0 related to RER at 60% of VO
2
peak (r=-0.47) and the change in RER (60%VO
2
peak-rest; r=-0.42) (P’s<0.05). G120 also related to the change in RER (r=-0.36) (P’s<0.05). Our results indicate that lower carbohydrate oxidation and the change in carbohydrate oxidation during exercise of increasing intensity are related to hyperglycemia in chronic stroke survivors. This inflexibility may limit the capacity to fulfill the energy requirements of daily physical activity performance, thereby heightening the probability of a more sedentary lifestyle post-stroke.
Abstract TP15: Futile Recanalization Rate and Predictors in Subjects With Anterior Circulation Occlusion in IMS-III Trial
Authors: Hussain Haitham M , Saleem Muhammad A , Qureshi Adnan I
Published: July 2021

Background:
The IMS-III trial was terminated early for futility after interim analysis showed no difference between intraarterial (IA) and intravenous (IV) treatment arms. This analysis is an attempt to understand the occurrence and predictors of futile recanalization in the IMS-III.

Materials and methods:
Data of IMS-III patients were treated with IA intervention was analyzed. Patients with near complete or complete recanalization (thrombolysis in cerebral infarction [TICI] gradesIIband III) were selected then divided, according to functional outcome at 3 months into “useful recanalization” - defined as modified Rankin scale (mRS) 0-2 and “futile recanalization” -mRS 3-6. Subjects with symptomatic intracerebral hemorrhage (ICH), posterior circulation occlusion, or missed data were excluded. Univariate analysis was performed to examine the differences between the two groups. Logistic regression was performed to identify the predictors of futility. Variables selected for the logistic regression are those significant in the univariate analysis.

Results:
Complete or near complete recanalization was observed in 145 of 434 patients treated with IA. Only 118 met the criteria for this analysis. Of those, 71 (60%) patients had useful recanalization and 47 (40%) had futile recanalization.Compared to patients with useful recanalization, patients with futile recanalization had higher incidence of diabetes mellitus, higher median baseline NIHSS scores (19 vs 15, p<0.001), higher median ASPECTS; 8 vs 7, longer time from onset to IV tPA (131 vs 116 min, p=0.026), longer time from onset to IA therapy (267vs 240 min, p=0.010), longer hospital stay (13±9vs 6±4 days, p<0.001), and a non-significant trend towards higher mortality rate (1.4% vs 10.6%, p=0.07). In logistic regression analysis,the only independent predictor of futile recanalization was baseline NIHSS≥20 (odds ratio, 4.1; 95% confidence interval, 1.1-16.4, p=0.043), while female gender, time to IV tPA, and ASPECTS showed a non significant trend.

Conclusions:
Futile recanalization is a relatively common following IA treatment in the IMS-III trial. Important clinical factors can predict this phenomenon, which is associated with high resources utilization without functional benefit
Abstract TP150: Incidence of Vascular Cognitive Impairment After the First-ever Stroke in Korea: The KOSCO Study
Authors: Kang Chung , Sohn Min Kyun , Kim Deog Young , Lee Jongmin , Lee Sam-Gyu , Shin Yong-Il , Oh Gyung-Jae , Lee Yang-Soo , Joo Min Cheol , Han Eun Young , Han Junhee , Chang Won Hyuk , Kim Yun-Hee
Published: July 2021

Objective:
This study aimed to analyze the incidence of vascular cognitive impairment (VCI) and factors influencing on VCI after the first-ever stroke.

Materials and Methods:
This is the interim result of the Korean Stroke Cohort for Functioning and Rehabilitation (KOSCO) designed as 10 years long-term follow-up investigating functions and quality of life. From August 2012 to May 2015, 4,490 patients completed Korean Mini-Mental Status Examination (K-MMSE) at 7 days, 3 months, 6months and 1year after stroke.

Results:
Among 4,490 patients, 77.2% of patients were ischemic and 22.8% hemorrhagic stroke, respectively. Their mean age was 64.3 and the gender ratio was 1.32:1 (M:F). Out of total patients, 1,596 patients (49.6%) suffered from cognitive impairment at 7 days; mild (MMSE 21 to 24) 16.0%, moderate (MMSE 11 to 20) 16.6%, severe (MMSE 0 to 10) 17.0 %, respectively. At 1 year after onset, some of patients showed improvement, however, 1,035 patients (32.2%) still showed to have cognitive impairment; mild 12.6%, modereate10.7%, and severe 8.9%, respectively. Factors influencing to cognitive impairment after stroke were age, initial severity of stroke and the duration of education (p<0.05). There was significantly better improvement of cognitive function at 1 year in patients who received inpatient rehabilitation (p<0.05).

Conclusion:
This study revealed the incidence and characteristics of cognitive recovery in patients with first-ever stroke in Korea. Results supported a recommendation to commence intensive rehabilitation during the hospitalization period to improve cognitive function.
Abstract TP159: Declines in Stroke-related Hospitalizations and In-Hospital Mortality Among Male and Female California Residents, 2000-2013
Authors: Ratnasiri Anura W , Ratnasiri Buddhika M , DiLibero Ralph
Published: July 2021

Background:
We examined stroke-related hospitalizations and in-hospital mortality trends by sex and age in California from 2000 to 2013.

Methods:
This retrospective analysis is based on data compiled by the California Office of Statewide Health and Planning Development from 2000 to 2013. Over 31.68 million inpatient events were studied, with cases from hospital discharge records identified as using the first listed diagnoses as ICD-9-CM codes 430 to 436. Hospitalization rates were expressed as the number of hospitalizations per 10,000 population and in-hospital mortality per 100,000 population, with the age and sex standardized to the year 2000 U.S. population.

Results:
We identified 1,060,006 hospitalizations and 77,908 in-hospital mortalities that were stroke-related from 2000 to 2013.

Hospitalization rates standardized for age and sex, significantly declined from 56.15 in year 2000 to 37.17 in year 2013, representing a 51.1% reduction (Rate Ratio (RR) 1.511; p <0.0001) during the study period. Rates for males declined from 52.7 to 36.6, representing a 43.8% reduction (RR 1.438; p<0.0001) and rates for females changed from 59.2 to 37.6, representing a 57.4% reduction (RR 1.574; p<0.0001. Although rates are declining for most age groups, hospitalization rates are rising for males age 35 to 59.

In-hospital mortality rates standardized for age and sex, significantly declined from 43.0 in 2000 to 25.0 in 2013, representing a 70.0% reduction (Rate Ratio (RR) 1.700; p <0.0001). Statistically significant declines in stroke-related in-hospital mortality rates were greater among females at 80.1%, while for males the decline was 62.6%. Overall, the rate difference for stroke hospitalization and in-hospital mortality among males and females narrowed significantly from 2000 to 2013.

Conclusion:
Stroke-related hospitalizations and in-hospital mortality declined substantially for both sexes, but at a greater rate among females over the 14 year study period. Although rates are declining overall for both sexes and most age groups, rates of stroke-related hospitalization and in-hospital mortality rose for males age 35 to 59.
Abstract TP19: Charlson Comorbidity Index Predicts Mortality and Functional Outcome in Acute Ischemic Stroke Patients Treated With Mechanical Thrombectomy
Authors: Samaniego Daniela , Hernandez-Perez Maria , Planas Anna , Martin Lorena , Dorado Laura , Lopez-Cancio Elena , Gomis Meritxell , Perez de la Ossa Natalia , Palomeras Ernest , Castaño Carlos , Davalos Antoni
Published: July 2021

Introduction:
Despite mechanical thrombectomy has achieved a dramatic improvement on ischemic stroke prognosis, up to 50% of patients treated with this approach do not have good functional outcome. Besides age and baseline infarct core, comorbidity might play a role in stroke prognosis. We aim to study the capacity of Charlson comorbidity index (CCI) in predicting mortality and functional outcome in acute ischemic stroke patients who underwent mechanical thrombectomy.

Methods:
We studied 228 consecutive patients (59% male, mean age 65y) with acute anterior circulation arterial occlusion treated with stent retrievers between May 2009 and March 2015. Demographical data, stroke severity, ASPECTS score at baseline and medical conditions included in the CCI were collected and CCI score was calculated retrospectively. We considered low comorbidity if CCI score was <2 and high comorbidity if CCI score was ≥2. Complete arterial revascularization was defined as a TICI ≥2b on final angiographic run. Good functional outcome was defined as a modified Rankin score ≤2 at 90 days.

Results:
The CCI was 0 in 47% of patients, 1 in 23%, 2 in 15%, 3 in 10% and ≥4 in 5%. CCI of 2 or more was associated with poor functional outcome (70.6% vs 50%, p = 0.004) and mortality (33.8% vs. 11.7%, p <0.001) compared to patients with low CCI. In a logistic regression adjusted by stroke severity, age, ASPECTS score at baseline and arterial revascularization, high comorbidity remained as an independent predictor of poor outcome (OR 2.9; 95% CI 1.4-5.8) and mortality (OR 4.6, 95% CI 2.0-10.3).

Conclusions:
High comorbidity assessed by Charlson Comorbidity Index is associated with poor functional outcome and mortality in acute stroke patients treated with mechanical thrombectomy.
Abstract TP219: Eight-minute Whole-brain Intracranial Vessel Wall MRI at 3 Tesla: Toward a Practical Imaging Protocol for Diagnosis of Stroke Etiology
Authors: Fan Zhaoyang , Yang Qi , Song Shlee , Guo Xiuhai , Deng Zixin , Sherzai Ayesha , Bi Xiaoming , Sherzai Dean , Li Debiao
Published: July 2021

Introduction:
T1-weighted variable-flip-angle 3D turbo spin-echo (TSE), has emerged as a vessel wall MRI technique promising for elucidating underlying intracranial vessel wall pathologies associated with stroke. Whole-brain 0.5-mm isotropic-resolution 3D TSE has recently been proposed at 3 Tesla. However, its scan time of 12 min renders it impractical for a clinical setting. This work aimed to design an expedited protocol and conduct a pilot study to demonstrate its potential for diagnosis of wall abnormalities.

Methods:
To expedite the acquisition, one may exploit an elliptical data sampling strategy and prolonged echo train length (ETL). However, this would reduce image SNR and compromise vessel wall delineation. On the other hand, SNR is intimately related to refocusing flip angles that are calculated for a prescribed tissue with specific T1 and T2 values (denoted as simulation T1 and T2). In this work, the effects of simulation T2 and ETL on the SNR/CNR performance were first explored on 9 healthy subjects. An optimized imaging protocol was then determined from a narrowed range of choices on 7 healthy subjects and finally applied to a pilot study of 10 patients with known wall disease.

Results:
Wall SNR, wall-CSF CNR, and white-gray matter CNR generally increased with simulation T2 and decreased with ETL. Optimization was focused on a narrowed range of protocol choices (ETL = 52; T2 = 140, 170, 200 ms) which enable a scan time of 8 min. ETL=52/T2=170ms was shown (Figure a.) to provide significantly higher (t-test) SNR/CNR performance than the original 12-min protocol (ETL=36/T2=100ms). With the 8-min protocol pre/post contrast, wall abnormalities (Figure b.) were correctly detected in all patients.

Conclusion:
An 8-min whole-brain intracranial vessel wall imaging protocol is developed which has demonstrated the potential of accurately identifying various wall abnormalities. A large-scale trial on using the technique for diagnosis of stroke etiology is underway.
Abstract TP221: A Novel Ultrasound Probe Attached to the Cervix Can Precisely Detect Large Patent Foramen Ovale
Authors: Mitsumura Hidetaka , Arai Ayumi , Sakuta Kenichi , Sakai Kenichiro , Terasawa Yuka , Kubota Jun , Iguchi Yasuyuki
Published: July 2021

Introduction:
We developed a novel probe (paste-able soft ultrasound probe; PSUP) attached to the cervix for detection of right-to-left shunt (RLS), because insufficient temporal bone window interrupts the precise examination for diagnosis of RLS.

Hypothesis:
We assessed the hypothesis that diagnostic ability of PSUP for RLS detection is equal to those of transesophageal echocardiography (TEE).

Methods:
Subjects were patients with ischemic stroke and transient ischemic attack who underwent TEE. PSUP was a 2.0-MHz center frequency, which had an equal property with TCD, and the shape was thin, soft, and square modified for attachment to the neck. At first, we performed TEE with the echoscope at the level of the fossa ovalis after injection of saline agitated with air in the right antecubital vein. The procedure was performed with and without Valsalva maneuver. Visualization of microembolic signals (MES) induced contrast agent within the right atrium and crossing the interatrial septum was considered as positive patent foramen ovale (PFO). We divided PFO into two groups according to number of MES, such as small PFO (1-29 of MES) and large PFO (≥30 of MES). Then, monitoring using PSUP was performed at unilateral common carotid artery (CCA) using similar preparation and procedure to TEE. RLS by PSUP diagnosed when we found 1and more MES in CCA. We compared detectable rate by size of PFO between TEE and PSUP, and calculated accuracy of PSUP against TEE.

Results:
From May 2014 to July 2015, 62 patients (46 male, mean age of 61 years) were included in this study. We diagnosed 26 of 62 patients (42%) as PFO by TEE, whereas PSUP detected in 17 of them (27%). As a reference of TEE findings, diagnostic ability of PSUP was 58% of sensitivity, 94% of specificity, and 79% of accuracy. In TEE examination, large PFO was 11 patients and small was 15 patients. PSUP could evaluate large PFO (9 of 11 patients) more accurately than small one (6 of 15, 82% vs. 40%, p=0.05).

Conclusion:
PSUP should have a considerable accuracy of large PFO diagnosis. For patients with insufficient temporal bone window, PSUP may play an important role of detecting large PFO.
Abstract TP230: Small Vessel Infarction as a Late Complication of Cranial Irradiation
Authors: Takenobu Yohei , Yoshida Kazumichi , Arakawa Yoshiki , Takagi Yasushi , Miyamoto Susumu
Published: July 2021

Background and Purpose:
Small vessel infarction after cranial irradiation is rare manifestation, whereas large vessel disease is well-known as a late complication. The purpose of this study is to investigate the clinical features of the small vessel infarction associated with the previous cranial irradiation.

Patients and Methods:
This is a retrospective chart review study of the patients presenting with small vessel infarction after cranial irradiation, retrieved from the single center database between 1998 and 2015. We reviewed the clinical characteristics, types and doses of irradiation, interval between first irradiation and first stroke, radiographic findings of the infarctions, and clinical courses.

Results:
Thirteen cases were identified, 12 men, 54 +/- 14 years of age at stroke onset. Underlying diseases for irradiation were 8 primary brain tumor, 4 metastatic brain tumor, 1 Leukemia, and 1 histologically undetermined brain tumor. Irradiation methods were 9 whole brain irradiation, 2 intensity modulated radiation therapy, and 2 local irradiation. Mean dose of irradiation was 51 +/- 10 Gy. Infarcted lesions were 8 corona radiata, 5 posterior limb of internal capsule, 1 thalamus. Mean time from first irradiation to first stroke was 14 +/- 14 years. Median NIHSS score at onset was 4 (min-max: 1-11), and median modified Rankin Scale at discharge was 3 (min-max: 1-4). One case had recurrence of infarction in the different territory of perforating artery, and one case had exacerbation due to infarction growth.

Conclusions:
Vasculopathy after irradiation also occurs in perforating arteries as well as in large vessels. Irradiation induced small vessel vasculopathy should be recognized as an important cause of stroke among brain tumor survivor.
Abstract TP237: Uneven Distribution of Stroke Patients and Stroke Centers
Authors: Alberts Mark J , Bhakta Nimisha
Published: July 2021

Background:
Texas is a large state with high demographic and geographic diversity. We analyzed the distribution of high-risk patients and stroke care hospitals to determine how to optimally distribute resources to benefit the largest number of patients.

Methods:
Data on overall state demographics were based on 2013 estimates derived from 2010 US census data. The number of hospitals was provided by the Department of State Health Services (DSHS). Stroke patients were ascertained via cms.gov and Texas DSHS data. Stroke data were available from 233 of 254 counties. Hospital designation in Texas is based on state-based criteria, but largely follows the definitions used by the Joint Commission.

Results:
Texas has approximately 26.4 million people (43% white, 39% Hispanic, 12% black, and 6% other). There are almost 3.3 million Medicare beneficiaries, of whom 94,071 have had a stroke. Texas has 649 hospitals with 84,000 licensed beds. There are 135 stroke facilities in 49 counties; 205 counties have no designated stroke facilities. Stroke designated hospitals include 12 CSCs, 110 PSCs, and 13 ASRH. There are 79 Critical Access Hospitals (CAH) that provide varying degrees of stroke care but have diverse locations (see map). The majority of Stroke Centers are located in or around large urban areas. The number of stroke patients varied significantly by county, with as few as 11 and as many as 12,844 in some counties. Many counties with large Medicare populations have few or no stroke centers.

Conclusions:
The distribution of stroke patients and stroke facilities in Texas is often mismatched. Processes to better match stroke resources with high-risk populations might improve stroke systems of care and perhaps outcomes. Conversion of some CAHs to ASRHs might alleviate some of these disparities.
Abstract TP25: Analysis of Workflow and Time to Treatment in the Swift Prime Randomized Controlled Trial
Authors: Goyal Mayank , Jadhav Ashutosh P , Bonafe Alain , Deiner Hans , Pereira Vitor , Levy Elad , Baxter Blaise , Jovin Tudor , Jahan Reza , Menon Bijoy , Saver Jeffrey
Published: July 2021

Background and Purpose:
Timely recanalization in large vessel occlusive disease is essential to achieving good outcomes in patients with AIS. As such, the SWIFT PRIME study design incorporated aggressive time metrics and real time direct feedback. We systemically investigated variables affecting the time spent during discrete patient process steps including patient transport, selection and treatment delivery in patients treated in the SWIFT PRIME trial.

Methods:
Data was analyzed from the SWIFT PRIME trial, a global, multi-center, prospective, randomized, open, blinded endpoint (PROBE) IDE study comparing functional outcomes in AIS subjects treated with either IV t-PA alone (93 patients) or IV t-PA in combination with Solitaire device (93 patients). Each patient enrollment was analyzed for workflow and direct feedback was provided to the enrolling site.

Results:
The median time from Emergency Department (ED) arrival to groin puncture was 90 minutes (interquartile range [IQR], 69 - 120) and ED arrival to reperfusion time was 139 minutes (IQR, 108 - 169). The median ED to imaging start time was 16 minutes (IQR, 10-23.5), puncture to device deployment was 24 minutes (IQR, 18-33), and device deployment to reperfusion was 8 minutes (IQR, 5-23). The association between time intervals and baseline characteristics of the patient, mode of arrival at the endovascular-capable hospital and procedural characteristics was evaluated with multivariate negative binomial regression using a logarithmic link function (Figure).

Conclusions:
Detailed attention to workflow with iterative feedback and aggressive time goals leads to a highly efficient workflow. Future steps for improvement include faster triage and transport of patients to endovascular capable centers as well as advancements in treating patients with difficult anatomical features.
Abstract TP250: Defining Technical Quality Standards for Mobile Telestroke Assessment: A Substudy of the Improving Treatment with Rapid Evaluation of Acute Stroke via Mobile Telemedicine (iTREAT) Mobile Telestroke Platform
Authors: Lippman Jason M , Sutton Zachary G , McMurry Timothy L , Gunnell Brian , Cote Jack , Solenski Nina J , Chapman Smith Sherita , Worrall Bradford B , Southerland Andrew M
Published: July 2021

Introduction:
In-ambulance use of remote videoconferencing for prehospital stroke assessment (mobile telestroke) is an emerging innovation in acute stroke care. As a new technology, there is a dearth of technical standards to ensure transmission quality and guide deployment in various EMS settings.

Hypothesis:
Subjective video quality ratings during in-vehicle mobile telestroke assessment correlate to objective video data transmission metrics.

Methods:
We performed videoconferencing via a low-cost, utilitarian mobile telestroke platform: tablet endpoint, high-speed 4G LTE modem, external antennae, HIPAA-secure videoconferencing application, and portable bracket mounting. We held test calls along typical ambulance routes recording transmission quality by a stationary and a mobile rater. We used a standardized 6-point scale of video quality: rating ≥ 4 deemed acceptable for mobile telestroke assessment. We recorded jitter, the variance in transmission data reception order, as simultaneously reported by the videoconferencing application.

Results:
We completed five test runs yielding 64 data ratings. Average jitter for ratings 1 through 6 was 434.9ms (SD = 407), 106.1ms (SD = 110), 41.4ms (SD = 29), 35.3ms (SD = 15), 29.5ms (SD = 6), and 29.0ms (SD = 2) respectively. Analyzing the raw data yielded an R2 of 0.41. As seen in Chart 1, video quality decreased as average jitter increased, but jitter values as low as 30ms were still seen across video transmission of all qualities.

Conclusion:
These preliminary data suggest modest correlation of transmission variance with subjective quality ratings using a low-cost mobile telestroke platform along rural-based ambulance routes. However, average transmission variance correlated highly (R2 = 0.93) suggesting more data ratings may improve the correlation. Testing of our mobile telestroke platform to assess performance and clinical efficacy as well as incorporate live acute stroke encounters is ongoing.
Abstract TP274: Orosomucoid-1 Protein Increases Following Ischemic Stroke in the Brain and Periphery
Authors: Mistry Hetal , Levy Madeline , Roy-O'Reilly Meaghan , McCullough Louise
Published: July 2021

Background and Purpose:
Orosomucoid-1 (ORM-1) is an abundant protein with important roles in inflammation and immunosuppression. We utilized RNA sequencing to measure mRNA levels in human ischemic stroke patients, with confirmation by serum ORM-1 protein measurements. A mouse model of ischemic stroke was then used to examine post-stroke changes in ORM-1 within the brain itself.

Hypothesis:
We tested the hypothesis that ORM-1 levels increase following ischemic stroke, with sex differences in protein dynamics over time.

Methods:
RNA sequencing was performed on whole blood from ischemic stroke patients (n=23) and controls (n=12), with Benjamini-Hochberg correction for multiple testing. Enzyme-linked immunosorbent assay was performed on serum from ischemic stroke patients (n=28) and controls (n=8), with analysis by T-test. For brain analysis, mice (n=14) were subjected to a 90-minute middle cerebral artery occlusion (MCAO) surgery and sacrificed 6 or 24 hours after stroke. Control mice underwent parallel “sham” surgery without occlusion. Western blotting was used to detect ORM-1 protein levels in whole brain, with analysis by two-way ANOVA.

Results:
RNA sequencing showed a 2.8-fold increase in human ORM-1 at 24 hours post-stroke (q=.0029), an increase also seen in serum ORM-1 protein levels (p=.011). Western blot analysis of mouse brain revealed that glycosylated (p=0.0003) and naive (p=0.0333) forms of ORM-1 were higher in female mice compared to males 6 hours post-stroke. Interestingly, ORM-1 levels were higher in the brains of stroke mice at 6 hours (p=.0483), while at 24 hours ORM-1 levels in stroke mice were lower than their sham counterparts (p=.0212). In both human and mouse data, no sex differences were seen in ORM-1 levels in the brain or periphery at 24 hours post-stroke.

Conclusion:
In conclusion, ORM-1 is a sexually dimorphic protein involved in the early (<24 hour) response to ischemic stroke. This research serves as an initial step in determining the mechanism of ORM-1 in the ischemic stroke response and its potential as a future therapeutic target for both sexes.