bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 2832: Rate of Change of ASPECTS can predict of outcome in Acute Ischemic Stroke patients undergoing Endovascular Therapy
Authors: Mehta Sonal , Kaushal Ritesh , Kitchener Jacob , Alshekhlee Amer , Komonchan Surasak , Chibnall John , Callison R. C , Edgell Randall , Feen Eliahu , Piriyawat Paisith , Cruz-Flores Salvador , Vora Nirav
Published: March 2022

Objectives:
We sought to assess how rate of infarction impacts outcome in acute ischemic stroke (AIS) patients undergoing endovascular therapy

Methods:
With institutional approval, we conducted a retrospective chart review on consecutive patients receiving endovascular treatment for anterior circulation AIS at our centers between January 2009 and June 2011. Beside patient’s demographics, we collected data on time from stroke onset to end of endovascular procedure, site of occlusion, and recanalization described as a Thrombolysis in Myocardial Infarction (TIMI) score ≥ 2. Neuro-imaging data included the immediate pre-treatment Alberta Stroke Program Early CT Score (ASPECTS). The ASPECTS score at onset was presumed to be 10. We calculated the rate of infarction as 10-ASPECTS/hour (ΔA). Our endpoint was good outcome defined as a modified Rankin Score ≤ 2 at 90 days. These parameters were entered into univariate and multivariate analyses to determine independent predictors of outcome.

Results:
Our cohort included 81 patients (45 females, mean age 67±12 years, median stroke score 17, median time from stroke onset to procedure completion 440 minutes). Occlusions were found in the middle cerebral artery (MCA) M2 (11), MCA M1 (46), intracranial internal carotid artery (ICA) (10), ICA origin (2), and tandem ICA origin with intracranial ICA or MCA occlusion (12). The mean baseline ASPECTS was 9 (75 patients had ASPECTS > 7). Recanalization was observed in 50%. The mean change in ASPECTS prior to endovascular therapy was 0.47 units/hour ± 0.72 units. Three parameters predicted a good outcome: recanalization (OR 10.1, 95% CI 2.7, 38.1, p < 0.001), recanalization in the setting of a pre-treatment ASPECTS score > 8 (OR 5.8, 95% CI 1.8, 19.3, p =0.002), recanalization in the setting of a ΔA < 1 unit/hour (OR 2.7, 95% CI 1.0-7.4, p =0.043). In a multivariate analysis controlling for stroke score, ΔA < 1 units/hour still impacted outcome (OR 3.1, 95% CI 1.1-8.9, p=0.039).

Conclusions:
While rate of infarction may impact the final outcome in patients receiving endovascular therapy for AIS, perhaps a better marker is recanalization in patients with a pre-treatment ASPECTS > 8. Rate of infarction may still be a valuable parameter when selecting patients for this endovascular therapy, in particular those being transferred to treatment sites.
Abstract 2861: Nursing and Rehabilitation Research Needed at the Point of Care
Authors: Akbar Jabar , Prvu Bettger Janet
Published: March 2022

Background:
Although scientific statements and clinical guidelines are useful summaries of the evidence intended to guide practice, the identification of the gaps in knowledge can be just as informative.

Purpose:
The aims of this project were to (1) identify the contributions of nursing and rehabilitation professionals to the evidence summarized in comprehensive overviews of nursing and interdisciplinary care for stroke patients; and, (2) present the opportunities where research could be developed in practice by nursing and rehabilitation professionals in an effort to strengthen the evidence for the care delivered to stroke patients.

Methods:
We examined the 2009 and 2010 American Heart Association Scientific Statements intended to guide nursing and rehabilitation professionals in the care of stroke patients and reviewed each of the articles cited. The number of articles and studies cited were summarized. The credentials and institution for the first and last author of every unique article were sought and analyzed to identify professional affiliation and the profession’s contribution to specific clinical recommendations. The recommendations in these statements were then analyzed to identify clinical areas where additional studies are needed or where the standard of care would benefit from systematic investigation.

Results:
These two scientific statements summarized data and information from 893 unique sources (912 references in total that included 780 empirical studies). Of the 780 studies included in these comprehensive overviews, only 7% were led by nurses or persons affiliated with a nursing school or clinical department (N=51). Rehabilitation professionals or persons affiliated with allied health schools or clinical rehabilitation departments led 27% of the studies included (N=214). Over 300 recommendations for care of the stroke patient were made. The majority of the recommendations were either Class I Level of Evidence C or Class IIa/b Level of Evidence B or C.

Conclusions:
Nursing and rehabilitation professionals provide much of the care summarized in these documents but have led few of the studies used to develop the evidence for it. Significant advances in science and quality will continue to be made but the significant gaps in evidence could be addressed, at least in part, with systematic investigation at the point of care by mentored nursing and rehabilitation professionals.
Abstract 2875: Effect of Mean, Maximum, and Variation of Blood Pressure in Patients with Ischemic Stroke during Antiplatelet Therapy
Authors: Uchiyama Shinichiro , Ikeda Yasuo , Horie Yoshiharu , Urano Yasuhisa , Yamaguchi Takenori
Published: March 2022

Background:
The Japanese Aggrenox Stroke Prevention vs. Aspirin Programme (JASAP) study was a double-blind, randomized clinical trial to compare the efficacy and safety of extended-release dipyridamole plus aspirin versus aspirin alone over 1 year in 1294 patients with non-cardioembolic ischemic stroke. We analyzed the effect of mean and maximum as well as variation of blood pressure on recurrence of ischemic stroke and intracranial hemorrhage (ICH) in patients enrolled in the JASAP study.

Methods:
We analyzed individual blood pressure at all visits including baseline, weeks 0, 1 and then every 4 weeks to a maximum of 124 weeks to compare mean and maximum systolic and diastolic blood pressure (BP) as well as standard deviation (SD) of variations of individual BP measurements.

Results:
Mean Systolic BP (SBP) for the last 3 months was significantly higher (140.6 mmHg vs. 135.4 mmHg, p = 0.002) in patients with than without ischemic stroke, while SD of variation of individual SBP measurements was significantly larger in patients with than without ICH (12.0 mmHg vs. 9.2 mmHg, p = 0.025). Mean diastolic BP (DBP) at the last visit was significantly higher in patients with than without ICH (84.0 mmHg vs. 78.1 mmHg, p = 0.012). Although ICH was tended to be more frequent in the highest tertile than in the lowest tertile of SD of variation of SBP (HR 1.513, 95% CI 0.298-2.286, p = 0.090) and of maximum SBP (HR 1.637, 95% CI 0.982-2.728, p = 0.059), such trend was not seen in ischemic stroke of SD of variation of SBP (HR 1.034, 95% CI 0.792-1.351, p = 0.804) and of maximum SBP (HR 0.925, 95% CI 0.699-1.225, p = 0.588)

Conclusion:
Despite of small sample size and different treatment arms, these results indicate that mean, maximum, and variation of SBP and DBP may affect differently on the occurrence of ischemic and hemorrhagic strokes in patients on antiplatelet agents.
Abstract 2878: Compliance to Guidelines by Emergency Medical Services in “Drip and Ship” Patients with In-transit Intravenous Thrombolytic Infusion
Authors: Asaithambi Ganesh , Chaudhry Saqib A , Hassan Ameer E , Rodriguez Gustavo J , Suri M F , Qureshi Adnan I
Published: March 2022

Background:
The “drip and ship” paradigm among acute ischemic stroke (AIS) patients has resulted in expansion of thrombolytic treatment in patients eligible for intravenous (IV) recombinant tissue plasminogen activator (rt-PA). However, it remains controversial whether the settings are adequate for IV rt-PA infusion within the EMS transport by emergency medical technicians (EMTs).

Objective:
To determine compliance to guidelines during transport of AIS patients treated with IV rt-PA using “drip and ship” paradigm while being transferred to comprehensive stroke centers (CSCs) from referring facilities and determine its effect on outcome upon discharge.

Methods:
A retrospective evaluation of patients transferred to our CSCs from June 2009 to July 2011 was conducted to determine the quality of care provided by EMTs after IV rt-PA was initiated at referring facilities. Quality parameters audited include frequency of blood pressure (BP) monitoring, interventions for elevated BPs, and discontinuation of IV rt-PA in the event of neurologic deterioration. Favorable outcome was defined as modified Rankin Scale (mRS) score ≤ 1 at time of discharge.

Results:
Among the 30 patients included in this study (53% men, mean age 72.6±14.2 years), 28 patients received vital sign monitoring at 10 to 20 minute intervals; the other two either underwent monitoring at less frequent intervals or did not receive any vital sign monitoring. The mean transit time was 37.4±16.9 minutes. Of the 29 patients with BP monitoring, 9 patients had at least one episode of BP above the recommended parameters (>180/105 mmHg) while being treated with IV rt-PA; only one of those was treated with an anti-hypertensive agent. No neurologic deterioration was reported during transit by EMS but 3 of the 30 patients were considered to have worsened between the outside ED and CSC ED evaluations. The rates of favorable outcome between patients who had interim neurologic deterioration without discontinuation of IV rt-PA or BP >180/105 mmHg without treatment was similar to those who experienced neither event (50% and 45%, p=0.55).

Conclusion:
Efforts are required to improve compliance to guidelines in patients receiving IV rt-PA during EMS transport in anticipation of broader use of “drip and ship” paradigm.
Abstract 2910: The Probability of Diffusion Weighted Imaging Evidence of Acute Infarction in Different Subsets of Transient Ischemic Attacks
Authors: Arsava Ethem Murat , Siket Matthew , Goldstein Joshua N , Furie Karen L , Ay Hakan
Published: March 2022

Background:
Since the 7-day stroke risk in DWI-normal TIA is negligibly low (0% to 0.4%), approximately 20 times lower than the corresponding risk after DWI-positive TIA, a clinically relevant question in the emergency setting is which patient with the clinical syndrome consistent with a TIA is likely to have MRI evidence of acute ischemia and should receive urgent imaging. This question has cost and management implications. We sought to determine the relationship between clinical TIA characteristics and the probability of detecting acute infarction on DWI in patients admitted to the emergency department with focal neurological symptoms lasting <24 hours.

Methods:
This was a retrospective, single center, emergency-based study of 586 consecutive patients. We explored the relationship between DWI positivity and the following clinical TIA characteristics: age, gender, symptom duration, symptom type, vascular risk factors, ictal headache, prior history of stroke or TIA, ABCD
2
score, and the type of spell (objective vs. subjective).

Results:
Univariate predictors of infarction on DWI included speech disturbance (OR=1.7, 95%CI 1.2-2.5), weakness (OR=2.3, 95%CI 1.6-3.3), visual symptoms (OR=0.4, 95%CI 0.2-0.7), isolated sensory symptoms (OR=0.3, 95%CI 0.2-0.60), subjective symptom (presenting with focal symptoms other than weakness or speech disturbance, OR=0.4, 95%CI 0.3-0.6), and ABCD
2
score≥4 (OR=1.6 95%CI 1.1-2.20). The positive predictive value for diagnosis of acute infarction on DWI was 38% for speech disturbance, 43% for weakness, 17% for visual symptoms, 16% for isolated sensory symptoms, 20% for subjective symptom, and 27% for ABCD
2
score≥4. Recursive partitioning analysis revealed a regression tree based on weakness, isolated sensory symptoms, and visual symptoms. According to this tree, the lowest probability for a given TIA patient to have a positive DWI was 17%.

Conclusions:
DWI provides diagnostic information in all subsets of TIA irrespective of clinical TIA characteristics. DWI is a valuable tool in the emergency management of TIA and offers potential to lead to improved TIA outcome particularly in settings where triage is based on clinical features.
Abstract 2918: Microbleeds and Periventricular hyperintensity on MRI Should Be Associated with Severe Sleep Disordered Breathing in Stroke and TIA Patients
Authors: Sakai Kenichiro , Shibazaki Kensaku , Uemura Jyunichi , Fujii Shuichi , Kimura Kazumi
Published: March 2022

Background and purpose
Several studies have reported that sleep disordered breathing (SDB) is a risk factor for stroke. A prior study demonstrated that white matter lesions on CT in stroke patients were associated with severe SDB. White matter lesions are thought to reflect ischemic damage to the small deep cerebral vessels. Therefore, white matter lesion should be strongly related with cerebral microbleeds (MBs), deep subcortical white matter hyperintensity (DSWMH), and periventricular hyperintensity (PVH) on MRI. Therefore, we hypothesized that severe SDB patients had more frequently such MRI lesions than non-severe SDB patients. The aim of the present study was to examine whether presence of MBs, DSWMH, and PVH on MRI were associated with severe SDB in stroke and TIA patients.

Methods
Between April 2010 and June 2011, patients with stroke and TIA patients within 24 hours from onset were prospectively enrolled. Subject underwent respiratory sleep studies within 7days after admission, and measured the respiratory disturbance index (RDI). Patients were classified into 2 groups, severe SDB group had RDI>30 and non-severe SDB group had RDI<30. The present study performed MRI on admission, and assessed the presence of cerebral MBs on T2* weighted imaging, the percentage of DSWMH and PVH grade (Grade0-1 or 2-3) according to Fazekas classification on FLAIR imaging. Univariate and multivariate logistic regression analysis were performed on clinical characteristics including vascular risk factors, and MRI findings between severe SDB and non-severe SDB patients.

Results
Two hundred and twenty patients were enrolled (mean age 71.8 ± 11.9 years, male 61%, TIA 16%, ischemic stroke 65%, and hemorrhagic stroke 19%). 66 (27.2%) patients had severe SDB and 154 (72.8%) had non-severe SDB. MBs (58% for severe SDB group vs. 40% for non-severe SDB group, p=0.019), PVH grade 2-3 (44.4% vs. 27.1%, p=0.021), atrial fibrillation (30.3% vs. 16.4%, p=0.028), body Mass Index (BMI) (23.8 ± 3.3kg/m2 vs. 22.3 ± 3.9kg/m2, p=0.012) were significantly higher in the severe SDB group than in the non-severe SDB group. DSWMH Grade 2-3 was not different between two groups (43.2% vs. 31.3%, p=0.142). Multivariate logistic regression analysis demonstrated that MBs (OR 2.2, 95%CI 1.1-4.3, p=0.022), PVH grade 2-3 (OR 2.0, 95%CI 1.1-3.8, p=0.046), and BMI>23kg/m2 (OR 2.6, 95%CI 1.1-5.2, p=0.008) were independently associated with severe SDB.

Conclusions
MBs and PVH should be associated with severe SDB in stroke and TIA patients.
Abstract 2939: Elevated Serum Soluble Lectin-like Oxidized Ldl Receptor-1(slox1)is Associated With Increased Ischemic Stroke Risk: A Case-control Study
Authors: Fukuda Mayumi , Yokota Chiaki , Kokubo Yoshihiro , Sawamura Tatsuya , Miyamoto Yoshihiro , Toyoda Kazunori , Minematsu Kazuo
Published: March 2022

BACKGROUND and PURPOSE:
Lectin-like oxidized LDL receptor 1 (LOX-1) is responsible for uptake of oxidized LDL. LOX-1 is released to serum in part as the soluble form (sLOX-1). LOX-1 is reported to play crucial roles in the pathogenesis of atherosclerotic plaque rupture. We showed previously that high sLOX-1 could be a predictive biomarker for acute coronary syndrome. The aim of this study is to examine the impact of sLOX-1 on ischemic stroke risk.

METHODS:
We enrolled consecutive 420 patients (257 men, 74±11 years) with ischemic stroke who were admitted to our hospital within 72 hours after the onset of stroke from August 2008 to August 2010. As healthy controls, we selected 1004 participants (430 men, 62±9.5 years) from the Suita Study,an population-based cohort in an urban area located same city with our hospital . As a baseline survey, we measured height, weight, BMI, drinking and smoking habits, history of hypertension, dyslipidemia and diabetes. We also obtained information of stroke subtypes from the case group. Morning blood samples after an overnight fast (within 72 hours after the onset in the case group) were used to evaluate sLOX-1. We measured sLOX-1 by using ELISAs with 2 monoclonal antibodies against LOX-1.

RESULTS:
Cases were consisted of 61 atherothrombotic, 142 cardioembolic, 75 lacunar infarctions, and 142 others. The measurement ranges of sLOX-1 were 102 - 6,167 (mean 777, median 527 ) ng/L for the case group and 104 -12,142 (mean 623, median 481) ng/L for the control group. The odds ratio (95% confidence intervals; 95% CI) for the risk of stroke in the highest quartile of sLOX-1 as compared with the lowest quartile was 1.72 (1.10-2.69 p=0.015) for all ischemic strokes after adjusting for sex, age, BMI, drinking, smoking, hypertension, dyslipidemia and diabetes. The odds ratios (95% CI) for the risk of each ischemic stroke subtypes was 3.74 (1.41-10.4 p=0.008) for atherothrombotic, 2.38 (1.28-4.46 p=0.006) for cardioembolic, 1.82 (0.78-4.23 p=0.16) for lacunar, 0.76(0.47-1.26 p=0.29) for others, respectively.

CONCLUSIONS:
Elevated sLOX-1 could predict the onset of ischemic stroke, especially for atherothrombotic and cardioembolic infarctions.
Abstract 2945: Missed Opportunities for Primary Stroke Prevention among Young Adults in the United States.
Authors: Muthusamy Arunkumar , Madhavan Ramesh , Bhattacharya Pratik
Published: March 2022

The incidence of stroke is increasing in young adults. However, little is known about primary prevention in this population. Prevention of stroke among young and early middle-aged adults is particularly important as they face with years of disability after a stroke. Our objective was to define the prevalence of modifiable stroke risk factors and steps taken to address them among the younger adults during outpatient clinic visits within the United States.

Methods:
Data from the 2008 and 2009 National Ambulatory Medical Care Survey dataset were analyzed. Young subjects (18 to 45 years) visiting medical specialties were selected. Weighted frequencies of diabetes, hypertension, tobacco abuse, hyperlipidemia, and obesity were estimated based on physician reported data about these conditions. Proportions of subjects receiving education about weight reduction, exercise, diet and nutrition, smoking cessation and prescriptions were estimated.

Results:
There were an estimated 324.7 million medical office visits in 2008 and 2009. The majority of these visits were to Internal Medicine (20.5%) and Family medicine (45.8%) practices, whereas (2.5%) visits were to neurologists. Smoking (20.6%) was the most prevalent risk factor recognized by physicians, followed by obesity (16.7%), hypertension (12.3%), hyperlipidemia (7.7%) and diabetes (6.6%). Only 19.5% of all smokers were documented to have received smoking cessation advice. Weight reduction counseling was provided to 15.8% of obese patients, 14.9% of hypertensive, 16.2% of diabetic and 13.9% of hyperlipidemic subjects. Diet and nutrition counseling was provided to 23.4% of obese, 24.9% of hypertensive, 30.1% of diabetics and 29.9% of hyperlipidemic subjects. Exercise was advised to 19.5% of obese, 17.6% of hypertensive, 20.6% of diabetics and 24.1% of hyperlipidemic subjects. Statins were prescribed to 91.1% of subjects with hyperlipidemia, 89.9% of diabetics were on insulin and 10.7% were on oral drugs, whereas only 13.6% of hypertensive subjects were on prescription medication.

Conclusion:
A substantial proportion of young adults are found to have modifiable stroke risk factors during office visits. There is a high use of prescriptions to treat hyperlipidemia and diabetes, however counseling regarding lifestyle changes is dismal. Efforts should be made fulfill the potential of the medical practioners in providing effective stroke prevention in young adults. Further research should concentrate on the systems of structured management of stroke prevention in primary care practice.
Abstract 2959: Diagnosis of Right-to-Left Shunt in Intracranial Vertebral Artery by Transcranial Color Flow Imaging
Authors: Mitsumura Hidetaka , Sakuta Kenichi , Furuhata Hiroshi , Mochio Soichiro
Published: March 2022

Objective:
Right-to-Left shunt (RLS) detection by Transcranial Doppler is useful for diagnosis of paradoxical embolism. However, we sometimes could not monitor MCA due to insufficient temporal bone window, especially in old patients. Other insonation windows such as transorbital and suboccipital window (basilar artery) are using recently, whereas the ability to detect of intracranial arteries from these windows was not so high. We evaluated usefulness of RLS detection in intracranial vertebral artery (VA) from suboccipital approach that could be measured in almost patients.

Methods:
We evaluated RLS using transcranial color flow imaging (TC-CFI) in patients with ischemic stroke or transient ischemic attack who could be detected middle cerebral artery (MCA) from temporal bone window and intracranial VA from suboccipital window by TC-CFI. We monitored microembolic signal (MES) at ipsilateral MCA and VA (not hypoplastic side) for 90seconds after injection of 9ml saline agitated with 1ml of air in the right antecubital vein. The procedure was performed three times in each artery with and without Valsalva maneuver. The presence of MES was classified according to Spencer Logarithmic Scale (SLS) criteria.

Results:
Fifty two patients (46 male, mean age of 64.1±14.3) were included. Twelve patients were positive of MES (23.1%). VA comparison to MCA showed 10 true positive, 40 true negative, 0 false positive and 2 false negative cases (sensitivity 83.3%, specificity 100%, positive predictive value 100%, negative predictive value 95.2% and accuracy 96.2%). In 12 patients with MES, 22 of 36 examinations in MCA were positive of MES (SLS grade I was 20 examinations and grade II was 2 examinations), on the other hand, 20 of 36 examinations in VA were positive (SLS grade I was 20 examinations). The positive ratio of 36 examinations in 12 patients did not show significant difference statistically between MCA and VA.

Conclusion:
The evaluation of RLS in intracranial VA using TC-CFI from suboccipital window has equal diagnostic ability to MCA, and is useful for the patients with insufficient temporal bone window.
Abstract 2964: A Novel Therapeutic Strategy For Experimental Stroke Using Docosahexaenoic Acid Complexed To Human Albumin
Authors: Belayev Ludmila , Khoutorova Larissa , Atkins Kristal D , Eady Tiffany N , Bazan Nicolas D
Published: March 2022

Background and Purpose:
Recently we have shown that docosahexaenoic acid (DHA; 22:6, n-3) and human albumin (Alb) is neuroprotective after experimental stroke. However, administration of high-dose Alb by expanding intravascular volume may lead to pulmonary edema and congestive heart failure. We suspected that if Alb were complexed with DHA, it might be possible to achieve neuroprotection at lower Alb doses.

Methods:
Male Sprague-Dawley rats were anesthetized with isoflurane/nitrous oxide and mechanically ventilated; rectal and cranial temperatures were regulated at 36-37.5
°
C. Rats received 2 h MCAo by retrograde insertion of an intraluminal suture. Animals received either DHA (5mg/kg), Alb (0.63g/kg), DHA-Alb (0.32, 0.63, 1.25g/kg) or an equivalent volume of vehicle (saline), which was administered at 3 h after onset of stroke into the femoral vein over 3 min using an infusion pump (n=8-10 per group). The neurological status was evaluated during occlusion (60 min), and on days 1, 2, 3 and 7 after MCAo; a grading scale of 0-12 was employed. Seven days after MCAo, brains were perfusion-fixed, and infarct areas and volumes were determined. Number of GFAP (reactive astrocytes), ED-1 (activated microglia/microphages) and NeuN (neurons)-positive cells were counted in the cortex and striatum at the level of the central lesion.

Results:
The physiological variables were entirely comparable among all groups. Animals treated with moderate doses of DHA-Alb (0.63 and 1.25g/kg) significantly improved the neurological score compared to Alb-treated rats by 21 and 26% on day 1; by 28 and 29% on day 2; by 36 and 40% on day 3; and by 42 and 35% on day 7 (respectively). The lowest dose of DHA-Alb (0.32g/kg) was not significantly different from the Alb-treated group. In addition, DHA treatment improved behavioral score compared to the Alb-treated rats, but only on day 2 (by 19%) and day 3 (by 26%). All doses of DHA-Alb (0.32, 0.63 and 1.25g/kg) significantly reduced total (cortical and subcortical) corrected infarct volume in all treated groups compared to Alb-treated rats (by 64, 60 and 61%, respectively). Cortical and striatal infarct volumes were also significantly reduced by all doses of DHA-Alb. DHA treatment alone significantly reduced only striatal infarct volume compared to the Alb-treated group (22±4 vs. 52±9, respectively).

Conclusions:
The DHA-Alb complex affords high-grade neurobehavioral neuroprotection in focal cerebral ischemia, equaling or exceeding that afforded by native Alb, at considerably moderate doses. It might provide the basis for future therapeutics in patients suffering ischemic stroke.
Abstract 2967: Recurrent TIA and Early Risk of Stroke
Authors: Purroy Francisco , Jiménez-Caballero Pedro E , Gorospe Arantxa , Torres MarÍa José , Álvarez-SabÍn José , Santamarina Estevo , Sánchez-MartÍnez Patricia , Cánovas David , Freijo Mar , Egido José A , Giron Juan M , RamÍrez-Moreno José M , Alonso Arantza , RodrÍguez-Campello Ana , Casado Ignacio , Delgado-Medeiros Raquel , MartÍ-Fábregas Joan , DÍez-Tejedor Exuperio , Silva Yolanda , Quesada Helena , Cardona Pere , Morales Ana , de la Ossa Natalia P , GarcÍa-Pastor Antonio , Arenillas Juan F , Segura Tomás , Jiménez Carmen , Montserrat Josep , Masjuán Jaime
Published: March 2022

Background:
Many guidelines recommend urgent intervention for TIA patients with 2 or episodes within 7-days to reduce the early risk of stroke. However, whether all patients with multiple TIAs are at high early risk of stroke is unknown.

Methods:
Between April 2008 and December 2009, we included 1255 consecutive TIA patients from 30 Spanish stroke centers (PROMAPA study). We prospectively recorded clinical characteristics. We also determined the early short-term risk of stroke (at seven and ninety days). Aetiology of TIA was categorised using the SSS-TOAST classification

Results:
Enough information was assessed in 1137 patients (90.6%). 7-day and 90-day stroke risk were 2.6% and 3.8% respectively. Atherosclerotic etiology (AE) was confirmed in 190 (16.7%) patients. Recurrent TIA was observed in 274 (24,1%) patients. Duration<1 hour (OR 2.94, 95% CI 2.18-3.96, p<0.001), AE (OR 1.97, 95% CI 1.39-2.78, p<0.001) and motor weakness (OR 1.37, 95% CI 1.03-1.82, p<0.029) were independent predictors of recurrent TIA. The subsequent risks of stroke in these patients at 7, and 90 days were significantly higher than those after a single TIA (5.8% versus 1.5%, p<0.001 and 6.8% versus 3.0%, respectively. HR 2.35, 95% CI 1.28-4.31 p=0.006). In the Cox logistic regression model, among patients with recurrent TIA, no variable remained remained as independent predictors of stroke recurrence at 90-day

Conclusion:
According to our results, recurrent TIA within 7-days is associated with a greater subsequent stroke risk than after a single TIA. Nevertheless, we were not able to find any independent predictor of stroke recurrence among these patients.
Abstract 2970: Inter-observer Agreement in Diagnosis of “Borderzone” Infarcts On Diffusion Weighted MR Imaging.
Authors: Jain Minal , Kung Nancy T , Jain Anunaya , Kanthala Abhijit R , Jahromi Babak S
Published: March 2022

Aim:
To evaluate consensus in diagnosis of “borderzone” infarcts on diffusion weighted MR imaging (DWI).

Methods:
DWI of 144 consecutive stroke patients were independently reviewed by blinded Neuroradiologists (n=2) and Vascular Neurologists (n=2) and classified into embolic versus borderzone infarct patterns. CT angiography studies of each of these patients were later reviewed to determine degree of ipsilateral carotid artery stenosis/occlusion by NASCET criteria. Subjects with any MCA occlusion/stenosis on any side were excluded.

Results:
The agreement between Neuroradiologists was fair (Kappa=0.22, 95% CI 0.089 to 0.351), agreeing on 61.8% as embolic and 7.64% as borderzone infarcts. The agreement between Vascular Neurologists was good (Kappa=0.722, 95% CI 0.55 to 0.893), agreeing on 84.14% as embolic and 9.66% as borderzone infarcts. Inter-rater agreement between Neuroradiologist and Vascular Neurologist pairs varied between fair to moderate (Kappa = 0.22 to 0.72). Overall Fleiss’ Kappa for all 4 raters was 0.373 (95% CI 0.306 to 0.439). Classification of infarct patterns by degree of carotid disease on CTA is shown in the
table
below. As is seen in the
table
above, infarct patterns in patients with 100% carotid occlusion were classified as borderzone by both Neuroradiologist and Vascular Neurologist pairs in less than 30% of patients. The Neuroradiologist pair commonly classified infarct patterns in 75% of patients with 70-99% stenosis as borderzone. The Vascular Neurologists too classified 80% of these patients with 70-99% stenosis as having a borderzone infarct. Amongst patients with <50% carotid stenosis, both pairs of raters classified >90% of infarct patterns as embolic.

Conclusions:
Carotid occlusion and near-occlusion were unexpectedly associated with a smaller proportion of borderzone infarction than 70-99% stenosis. Discrepancies between Neuroradiologists and Vascular Neurologists towards diagnosis of watershed infarcts suggest the need to develop common definitions/guidelines. MR DWI imaging may not be a sole/sufficient criterion to classify watershed versus embolic infarction.
Abstract 2984: Optical-resolution Photoacoustic Microscopy: a Novel Imaging Modality Capable of Noninvasively Measuring Brain Oxygen Metabolism at the Microvascular Level during Focal Ischemia
Authors: Lee Jin-Moo , Hu Song , Gonzales Ernesto , Soetikno Brian , Gong Enhao , Zhong Qiaonan , Maslov Konstantin , Wang Lihong V
Published: March 2022

Studying oxygen metabolism during brain ischemia has been limited by imaging modalities that have either low resolution but good tissue penetration, or high resolution requiring invasive preparations (open-skull windows). Here, we report a study of cerebrovascular oxygen metabolism in mouse focal ischemia using a novel minimally invasive, high-resolution technique known as optical-resolution photoacoustic microscopy (OR-PAM). Using OR-PAM, we serially imaged cortical vessels through the intact skull of Swiss Webster mice (n=3) before, during, and up to 72 hrs after a 1-hr intraluminal transient middle cerebral artery occlusion (MCAO). Vessels were imaged at 2 different wavelengths (532 & 563 nm) to quantify oxy-, deoxy-hemoglobin and oxygen saturation (sO
2
,
Fig
, A-C). Oxygen extraction fraction (OEF) was calculated from venous sO
2
values (assuming a constant arterial sO
2
of 95%). Seventy-two hrs after ischemia, animals were sacrificed and whole brains were stained with TTC to delineate infarct at the cortical surface (D). Arterioles were easily distinguished from venules in baseline images (A, mean arterial sO
2
, 87%; mean venous sO
2
, 76%). During MCAO, mean arteriolar sO
2
values did not change; however, venular sO
2
decreased precipitously (B, E), greater in regions that went on to infarct (45±2%) compared to surrounding regions (52±2%, p<0.001). Three and 7 hrs after reperfusion, venous sO
2
slowly recovered but not back to baseline levels. Twenty-four (C) and 72 hrs after reperfusion, venous sO
2
in regions of infarction increased above baseline (83%), approaching arterial sO
2
values of 90%, while venous sO2 in peri-infarct regions (71%) returned near baseline levels of 76% (E). OEF increased from 18% to 55% in regions of eventual infarction, during MCAO; following reperfusion, OEF progressively dropped below baseline levels (12%). In surrounding surviving tissue, OEF returned close to baseline levels (24%) following reperfusion (F). OR-PAM is capable of measuring oxygen metabolism at high resolution during focal ischemia. Consistent with previous PET studies in human stroke, we found OEF increased during acute ischemia; however, OEF remained elevated (above baseline values) after reperfusion, suggesting that injured tissue may have increased oxygen metabolism. OEF gradually decreased below baseline values in infarcted tissue, but returned to near-baseline values in viable peri-infarct regions.
Abstract 2986: Bilateral Thalamic Lesions in Subcortical Vascular Dementia
Authors: Nagata Ken , Yamazaki Takashi , Takano Daiki , Maeda Tetsuya , Satoh Yuichi , Nakase Taizen
Published: March 2022

Subcortical vascular dementia (SVaD) is categorized to the group of dementia due to the small-vessel disease which consists of lacunar infarcts, microbleeds and leuko-araiosis. However, the causative lesions and their relationship have not been clarified yet in SVaD. In order to elucidate the pathophysiology underlying SVaD, MR findings and vascular risk factors were analyzed in 31 patients (25 men and 6 women) who were diagnosed as having SVaD based on the NINDS-AIREN criteria. Their mean age was 75.7 years. Thirty-six non-demented patients with asymptomatic cerebral infarction (ACI) and 49 non-demented patients with symptomatic lacunar infarcts (SCI) served as disease controls. All subjects underwent 1.5 Tesla MRI including T1WI, T2WI, T2*WI, FLAIR and MR angiography. Numbers of lacunar infarcts and old microbleeds were counted in all MR slices, and the degree of leuko-araiosis was evaluated according the Fazekas’ categories. Laboratory studies included fibrinogen, d-dimer, serum lipid profile, glucose, plasma immunoreactive insulin (IRI) and brain natriuretic peptide (BNP). In the neuropsychological evaluation, MMSE, clock drawing test (CDT) and Benton’s visual retention test (BVRT) were carried out. In the results, the mean MMSE score was 13.0, and the mean CDT was 2.7/5.0. In the MR findings, the mean number of lacunar infarcts was 11.4, 15.2 and 17.2 for ACI, SCI and SVaD group, respectively. Thalamic lesions were detected in 30 (96.8%) of 31 SVaD patients, and 86.6% were lacunar infarcts whereas 13.3% were microbleeds on T2*WI. Bilateral thalamic lesions were detected in 66.7%, and the right-side and left-side lesions were seen in 16.6%, respectively. Antero-medial thalamic lesion was detected in 23.3%. No bilateral thalamic lesions were found in ACI or SCI group. Microbleeds were detected in 90% of SVaD patients. The mean number of microbleeds was 1.3, 2.1 and 5.8 for ACI, SCI and SVaD group, respectively. In the laboratory studies, the mean fibrinogen was significantly greater in SVaD group than in ACI or SCI group. The mean insulin was significantly greater in SVaD group than in ACI and SCI group. Advanced leuko-araiosis (Grade II and III) was seen in 87.1% of SVaD patients, whereas 52.8% of ACI patients and 34.7% of SCI patients. In the laboratory studies, the mean fibrinogen, IRI and BNP were significantly greater in SVaD group than in ACI or SCI group (p<0.05). The mean ratio of LDL-cholesterol to HDL-cholesterol was significantly greater in SVaD and SCI groups than in ACI group (p<0.05). In the present results, thalamic lesions, especially bilateral thalamic lesions, were detected frequently in SVaD patients. As thalamus plays an important role in both medial limbic and basolateral limbic systems which mediate cognitive information processing including memory and emotion, thalamic lesions may redound to the formation of SVaD.
Abstract 2994: Acute Ischemia in Broca's Area is Associated with Apraxia of Speech and Phonological Short-Term Memory Deficit
Authors: Townsley Sarah H , Hickock Gregory , Hillis Argye E
Published: March 2022

Background:
Apraxia of speech (AOS) is commonly thought of as a motor programming deficit, but could be due to impaired ability to maintain the sequence of phonemes (speech sounds) in short-term memory (STM) while articulating the word. We hypothesized that AOS and impaired digit span are associated with acute ischemia (infarct and/or hypoperfusion) of pars opercularis of Broca’s area (Brodmann's area 44), and that severity of AOS and digit span would be strongly correlated.

Methods:
We tested 87 patients on the first day of admission for left hemisphere acute ischemic stroke (mean age= 60.0±15.9; mean education 13.6±3.7 years) with Apraxia Battery for Adults-II and digit span tests and MRI, including Diffusion and Perfusion Weighted Imaging (DWI, PWI). We defined Apraxia of Speech (AOS) as 3 or 4 abnormal scores on the subtests of ABA-II: Words of Increasing Length A and B (which scores an increase in articulatory errors with increased word length for short and longer words/phrases, respectively), Repeated Trials (which scores variability in errors in repetition of the same polysyllabic words), and Inventory of Articulation (which scores characteristics of AOS). We defined impaired phonological STM as forward digit span < 5 or backward digit span < 3. The first author and 1 other technician, masked to the AOS results, examined MRI DWI and PWI scans for the presence or absence of ischemia (bright on DWI and/or hypoperfused on PWI) in each of 12 regions of interest: Brodmann’s area (BA) 4, 6, 10, 11, 19, 20, 21, 22, 37, 38, 39, 40, 44, 45, anterior and posterior insula. Hypoperfusion was defined as > 4 sec delay in TTP compared to opposite hemisphere. We evaluated association between the ischemia in each Brodmann area (BA) and (1) presence of AOS and (2) impaired STM using chi square tests.

Results:
AOS was significantly associated only with BA 6 (premotor cortex; chi square= 7.07; df1; p<.003) and BA 44 (pars opercularis of Broca’s area; chi square= 5.3; df1; p<.02), but not BA 45 (pars triangularis) or other ROIs. Impaired STM measured by forward digit span <5 was associated with BA 6 (chi square= 20.2; df1; p<.000001) and BA 44 (chi square= 15.2; df1; p=.00009), and BA 45 (chi square= 19.2; df1; p=.0001). There was strong correlation between digits forward span and Repeated Trials score (r=.35; p=.003), either because both speech articulation and STM rely on Broca’s area, or because orchestration of speech articulation demands holding phoneme sequences in phonological STM.

Conclusions:
Acute ischemia of the pars opercularis of Broca’s area (Brodmann’s Area 44) is associated with AOS and STM deficits. The severity of AOS and digit span deficits were highly correlated. The relationship between AOS and phonological STM begs further investigation.
Abstract 30: The Frailty Index: A Novel Predictor Of Stroke Outcomes
Authors: Haque Sulsal , Reeves Mathew J , Sucharew Heidi , Alwell Kathleen A , Moomaw Charles J , Woo Daniel , Flaherty Matthew L , Khatri Pooja , Adeoye Opeolu , Ferioli Simona , Kleindorfer Dawn , Kissela Brett M
Published: March 2022

Background:
There is little research that examines the impact of frailty on stroke outcomes. The objective of our study was to develop a frailty index (FI) and analyze its relationship to stroke outcomes in a nationally representative population-based study of ischemic stroke.

Methods:
Within a population of 1.3 million, all ischemic strokes among Greater Cincinnati/Northern Kentucky residents in 2005 were ascertained from local hospitals and clinics using ICD-9 discharge codes 430-436 (n=2226). Using previously validated methodology, a FI was created based on 35 age-related deficits including co-morbidities (e.g. prior stroke, dementia), pre-stroke functional status (e.g. as measured by the modified Rankin Scale [mRS], use of walking aids) and admission lab values (e.g. abnormal creatinine, hemoglobin). The FI for each subject (expressed as a %) was calculated as the number of deficits divided by the maximum number (n=35). Multiple logistic regression models were used to examine the association between the FI and in-hospital mortality, poor functional outcome (discharge mRS≥3), and discharge to home, with adjustment for age, sex, race, and NIH Stroke Scale score. Odds ratios were specified for a 3% increase in the FI (which is approximately equivalent to a 1 deficit increase in the FI i.e. 1/35)

Results:
The median age of the study sample was 73 years and the median FI was 17% (IQR 11%-26%). The in-hospital mortality was 10%. Amongst survivors, 53% were discharged with an mRS≥3 and 68% were discharged home. Logistic regression models demonstrated that after adjustment, for every 3% increase in the FI, the odds of dying in hospital increased by 16% (p<0.01), the odds of being discharged with an mRS≥ 3 increased by 8% (p<0.01) and the odds of being discharged home was decreased by 7% (p<0.01). (
Table
)

Conclusions:
Frailty was associated with increased in-hospital mortality, poorer outcome at discharge (mRS≥3) and decreased likelihood of being discharged home. Importantly frailty’s effects on stroke outcomes were shown to be independent of age, which suggest that frailty may represent a biological rather than chronological measure of aging. Further work needs to be done to examine the relationship between frailty, its sub-components and stroke outcomes. Frailty indices may represent an important new contribution to prognostic models of stroke.
Abstract 3013: Cerebral Perfusion Parameter Differences in Clinically Relevant Categories of Carotid Stenosis/Occlusion.
Authors: Kung Nancy T , Jain Anunaya , Jain Minal , Kanthala Abhijit R , Jahromi Babak S
Published: March 2022

Hypothesis:
To determine whether clinically relevant categories of carotid stenosis are associated with changes in cerebral blood flow.

Methods:
We examined a consecutive cohort of stroke patients with confirmed stroke on DWI imaging who underwent CT angiography (CTA) and perfusion CT imaging on presentation with acute symptoms. Degree of carotid stenosis was measured per NASCET criteria on CTA. Perfusion CT was analyzed to calculate relative mean transit time (rMTT), relative cerebral blood volume (rCBV) and relative cerebral blood flow (rCBF) of normal brain tissue ipsilateral to carotid disease. Measurements excluded areas of infarction to avoid confounding hemispheric perfusion changes with local changes due to distal cerebral artery occlusion(s), and subjects with MCA occlusions on any side were excluded.

Results:
The cohort consisted of 119 patients. Of these 8.4% had 100% ipsilateral carotid occlusion, 1.7% had near-occlusion, 5% had 70-99% stenosis, 5.9% had 50-69% stenosis, and 79% had <50% stenosis. Subjects with 100% carotid occlusion had a higher rMTT (median 1.503, IQR 0.974 to 2.44; p=0.02) when compared to the expected normal rMTT of 1.0. These patients also had a lower rCBF (median 0.708, IQR 0.553 to 1.116; p=0.048) when compared to the expected normal rCBF of 1.0. Perfusion parameters of subjects with carotid near-occlusion did not differ significantly from the expected normal values. Subjects with 70-99% stenosis had slightly higher rMTT (median 1.246, IQR 1.034 to 1.422; p=0.031) and slightly higher rCBV (median 1.088, IQR 1.046 to 1.142; p=0.031) when compared to the expected normal of 1.0. Subjects with 50-69% carotid stenosis and <50% stenosis did not have significantly different perfusion parameters when compared to expected normal values.

Conclusions:
This is the first reported correlation between clinically relevant categories of carotid stenosis and perfusion parameters measured by perfusion CT imaging of the brain. Subjects with 100% occlusion appeared to have hemodynamically significant changes in perfusion (increased rMTT by ∼50%, decreased rCBF by ∼30%). Patients with 70-99% stenosis had less pronounced changes in rMTT, and no change in rCBF. Interestingly, patients with carotid near-occlusion showed no significant change in perfusion parameters, suggesting that this subgroup of patients may have developed sufficient collateral circulation. Patients with 0-69% stenosis had no significant changes in perfusion parameters. These findings may have significant implications in our approach to patients with carotid occlusion/stenosis and need to be confirmed in larger patient populations.
Abstract 3026: Prediction of Left Atrial Appendage Thrombus and Severity of Left Atrium Blood Stasis by CHADS-VASc and CHADS
2
Authors: Mazur Matylda , Ammash Naser , Asirvatham Samuel , Grill Diane , Slusser Joshua , McBane Robert D , Wysokinski Waldemar E
Published: March 2022

BACKGROUND.
Nearly half of strokes in non-valvular atrial fibrillation (NVAF) are due to non-cardioembolic mechanisms including carotid disease, lacune, watershed, venous sinus thrombosis, or hemorrhage. Tools capable of identifying those AF patients most likely to suffer a cardioembolic complication of AF would be very helpful for deciding which patients to treat with anticoagulants compared to aspirin. CHA
2
DS
2
-VASc has been advocated as an improved stroke risk assessment tool for NVAF patients.

METHODS.
CHA
2
DS
2
-VASc was compared to CHADS
2
for the prediction of left atrial appendage thrombus (LAAT), and association (Spearman correlation) with spontaneous echo contrast (SEC), left atrium appendage emptying velocity (LAAEV), left atrium volume index (LAVI) in consecutive NVAF patients undergoing echocardiographic study (10/1/2007 - 9/30/2009).

RESULTS.
525 NVAF patients (age 62±13 years; 25% women; 28% persistent AF and 17% permanent AF) were parsed by extent of atrial blood stasis/LAAT (
Table
). CHA
2
DS
2
-VASc and CHADS
2
were similar for the prediction of LAAT (Figure). Measures of SEC intensity (0.416 vs 0.414;), LAAEV (-0.393 vs -0.344), and LAVI (0.322 vs 0.303) carried similarly associations with CHA
2
DS
2
-VASc and CHADS
2
scores.

CONCLUSION.
The challenge of stroke prevention in NVAF is balancing the risk and benefit of anticoagulant therapy. CHA
2
DS
2
-VASc does not improve the identification of patients with LAAT or low atrial mechanical function compared to CHADS
2
. Moreover CHA
2
DS
2
-VASc appears to overestimate the score of low risk patients for whom antiplatelet therapy would be sufficient and is more cumbersome compared to the original CHADS
2
.