bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract TMP71: Timing of Carotid Revascularization Procedures After Ischemic Stroke
Authors: Gupta Ajay , Gialdini Gino , Pandya Ankur , Navi Babak , Kamel Hooman
Published: July 2021

Background:
A 2004 report from two trials of carotid endarterectomy (CEA) indicated that its benefit was greatest when performed within 2 weeks of stroke onset. In 2006, the AHA recommended that carotid revascularization generally occur within 2 weeks of stroke.

Hypothesis:
Since 2005, the time between stroke and CEA or carotid artery stenting (CAS) has decreased and the proportion of patients undergoing CEA or CAS within 2 weeks has increased.

Methods:
Using administrative claims data from all nonfederal hospitals in CA, FL, and NY, we identified patients hospitalized with ischemic stroke between 2005 and 2012. We excluded those who did not undergo CEA or CAS within 90 days of admission for the index stroke. When stroke and CEA/CAS were documented in the same hospitalization, we included only strokes coded as present on admission so as to exclude periprocedural strokes in previously asymptomatic patients. All diagnoses and procedures were identified using previously validated ICD-9-CM codes. Our outcomes were the number of days between stroke and CEA/CAS and the proportion of patients who underwent CEA/CAS within the recommended 2-week period. Temporal trends were assessed using nonparametric correlation, chi-square test for trend, and logistic regression.

Results:
We identified 14,414 patients with ischemic stroke who underwent CEA or CAS within 90 days. The median (interquartile range [IQR]) number of days from stroke to CEA/CAS decreased from 25 (5-48) in 2005 to 6 (3-24) in 2012 (P <0.001; Figure 1A). The proportion of patients who underwent CEA/CAS within 2 weeks of stroke increased from 40.1% in 2005 to 69.9% in 2012 (P <0.001; Figure 1B). The temporal trends in both outcomes were significant even after adjustment for patient demographics, state of residence, and comorbidities.

Conclusions:
Since 2005, revascularization for symptomatic carotid disease has been progressively occurring sooner after presentation with stroke.
Abstract TMP84: Reducing Door to Needle and Door to Reperfusion Times: The Trim Effect
Authors: Rowell Marguerite
Published: July 2021

Background and Purpose:
One minute of brain ischemia can kill 2 million nerve cells and 14 billion synapses. The more time that elapses before IV thrombolysis or mechanical reperfusion, the slimmer the odds of a successful outcome. Early in fiscal year 2015, the Door-To- Needle (DTN) and Door-To-Reperfusion (DTR) times at our comprehensive stroke center rose to 78 min and 165 min, respectively. Also, the rate of IV tPA administration within 60 min decreased to 17%. In January 2015, lean methodology, specifically, Teams Refocus Imagine Measure (TRIM) was used to reduce DTN and DTR times. The purpose was to achieve: DTN < 60 min, DTR < 120 min, and rate of IV tPA given within 60 min > 75%.

Methods:
The TRIM and the Plan-Do-Check-Act methods were used to improve outcomes. Components included value stream mapping, A3 problem solving, and real-time observations to identify barriers, duplications and wasted time. The team consisted of Neurology, Neurosurgery, Nursing, Emergency Medicine, Emergency Medical Systems (EMS), Interventional Services (IVS), Radiology, Pharmacy, Anesthesia, Laboratory, Registration, Social Work, Risk Management, Transfer Center, Research, and Performance Improvement. Median and average times and percent compliance were calculated for pre-TRIM and post-TRIM data. Some interventions included:

• Designated ED trauma room for all strokes

• Early entry of acute stroke orders

• Use glucose and EKG from EMS for acute evaluation

• One-call stroke alert

• Advance tPA mixing

• Advance CTA contrast preparation

• Notification of parking lot arrival by on-call IVS Team

• Advance anesthesia consent

• Early discussion with patient and family regarding tPA

• Timely communication of turnaround times for each stroke alert

Results:
In the first two weeks after implementing changes, 23 min was reduced from the stroke alert response. In five months, DTN decreased to 51 min and 63 min was eliminated from DTR.

Conclusion:
Through an organized multidisciplinary team approach using standardized process improvement methods, identified best practices, and out-of-the-box thinking, improved stroke turnaround times were achieved to provide quality patient care and improve patient outcomes.
Abstract TMP92: Higher Risk of Ischemic Events in Secondary Prevention for Patients With Persistent Versus Paroxysmal Atrial Fibrillation: The SAMURAI-NVAF Study
Authors: Koga Masatoshi , Yoshimura Sohei , Hasegawa Yasuhiro , Shibuya Satoshi , Ito Yasuhiro , Nakashima Takahiro , Takamatsu Kazuhiro , Nishiyama Kazutoshi , Todo Kenichi , Kimura Kazumi , Furui Eisuke , Terasaki Tadashi , Shiokawa Yoshiaki , Kamiyama Kenji , Takizawa Shunya , Okuda Satoshi , Okada Yasushi , Kameda Tomoaki , Nagakane Yoshinari , Yagita Yoshiki , Kario Kazuomi , Shiozawa Masayuki , Sato Shoichiro , Arihiro Shoji , Yamagami Hiroshi , Toyoda Kazunori
Published: July 2021

Background and purpose:
The discrimination between paroxysmal and persistent atrial fibrillations (AF) has not been considered to guide secondary stroke prevention, because it remains unclear whether patients with persistent AF are at higher risk compared with paroxysmal AF, particularly in secondary prevention. We aimed to assess the differences in clinical outcomes between mostly anticoagulated patients with persistent vs. paroxysmal AF who had ischemic stroke or TIA.

Methods:
Using interim data of 1192 nonvalvular AF (NVAF) patients with acute ischemic stroke or TIA who were registered in the SAMURAI-NVAF study (an ongoing prospective, multicenter, observational study) to determine choice of anticoagulantion therapy and clinical outcomes, we divided patients into those with paroxysmal AF and those with persistent AF. We compared clinical outcomes between the 2 groups.

Results:
The median follow-up period was 1.0 year (IQR 0.3-2.0). Of the 1192 patients, 434 (191 women, 77.3±10.0 y.o.) and 758 (336, 77.9±9.9) were assigned to the paroxysmal AF group and persistent AF group, respectively. Of each group, 220 (50.7%) and 442 (58.3%) were anticoagulated with warfarin and 199 (45.9%) and 276 (36.4%) were so with non-vitamin K antagonist oral anticoagulant (NOAC) (p=0.004). As for primary outcomes, 30 (6.2%/person-year) and 78 (9.9) ischemic events, respectively [hazard ratio adjusted for sex, age, initial NIHSS, CHADS2 score, creatinine clearance, anticoagulation with warfarin (vs. NOAC) (HR) 0.65; 95% CI 0.42-0.98], and 18 (4.9%/person-year) and 31 (3.8) hemorrhagic events, respectively (HR 0.97, 0.52-1.75), occurred during follow-up. As for secondary outcomes, the person-year rate of ischemic stroke or TIA was 3.9% and 8.4%, respectively (HR 0.46, 0.27-0.76), that of intracranial hemorrhage was 1.6% and 1.7%, respectively (HR 0.97, 0.36-2.37), and that of death was 11.1% and 15.7%, respectively (HR 0.90, 0.64-1.26).

Conclusions:
Among patients with prior ischemic stroke or TIA, those with persistent AF had a higher risk of ischemic events, and ischemic stroke or TIA compared with those with paroxysmal AF. The prevention of progress to persistent AF from paroxysmal AF may be beneficial for secondary prevention in patients with NVAF.
Abstract TMP96: Optimal Combination Drug Therapy and Clinical Outcomes After Stroke by Obesity Status
Authors: Park Jong-Ho , Ovbiagele Bruce
Published: July 2021

Background:
Of various explanations for the ‘obesity paradox’ that lean people with cardiovascular diseases are more likely to have poorer outcomes vs. obese, one hypothesis is that obese patients display a readily identifiable high vascular risk phenotype that may lead to receiving or seeking earlier/more aggressive treatment.

Objective:
To examine whether lean stroke patients are less likely to receive optimal combination treatment (OCT) and explore a differential impact of combination therapy on clinical outcomes in lean stroke patients.

Methods:
We analyzed a clinical trial dataset comprising 3643 recent (<120 days) ischemic stroke patients followed up for 2 years. Subjects were categorized as having lean body mass index (BMI, <25 kg/m2, n=1006), overweight BMI (25 to 29.9 kg/m2, n=1493), and obese BMI 30 <kg/m2, n=1144). Subjects were categorized by level 0 to III depending on the number of the secondary prevention prescription divided by the number of drugs potentially indicated for each patient (0=none of the indicated medications and III=all indicated medications as OCT). Independent associations of each BMI category with all-cause death and major vascular events (stroke/myocardial infarction/vascular death) were assessed.

Results:
All-cause death occurred in 7.3% in lean, 5.5% in overweight, and 5.1% in obese patients. Frequency of OCT (level III) was 45.8% in lean, 51.7% in overweight, and 55.3% in obese patients. Subjects with lower BMI status had lesser frequency of OCT (45.8% in lean, 51.7% in overweight, and 55.3% in obese; P<0.001). Obese (vs. lean) patients were less likely to experience death (HR 0.70; 95% CI: 0.50–0.99, P=0.034), although this decreased risk was slightly attenuated and not significant after multivariable adjustment and was not seen with major vascular events. In multivariable analyses, compared with levels 0 and I, level II and level III were linked to lower risk of major vascular events (0.55; 0.32-0.95 and 0.48; 0.28–0.83) and death (0.44; 0.21-0.96 and 0.23; 0.10–0.54) among lean patients.

Conclusions:
OCT of secondary prevention medication after a recent ischemic stroke is less frequent in lean (vs. obese) patients, but when implemented is related to significantly better clinical outcomes among lean patients.
Abstract TP10: Prediction of Thrombolytic Efficacy: Usefulness of Measurement of Enhancement in the Thrombus on Thin-reconstructed Perfusion CT
Authors: Shin Dong Hoon , Kim Eung Yeop
Published: July 2021

Purpose:
To directly measure enhancement in acute thrombi using thin-reconstructed perfusion CT images for prediction thrombolytic efficacy.

Materials and Methods:
Prior to administration of tissue plasminogen activator (tPA), noncontrast CT (NCCT), 60-second 70-kVp adaptive 4D spiral CT (CTP), and CT angiography (CTA) were prospectively obtained and reconstructed at 1-mm thickness. Length and Hounsfield unit ratio (HUr) of thrombus were measured using 1-mm NCCT. Collateral circulation was assessed on dynamic CTA that were reconstructed from 1-mm CTP images. Good collateral circulation was defined as the criteria that were used for ESCAPE trial. After spatial motion correction of 1-mm CTP images, circular regions of interest were drawn in the central portion and each end of thrombus to measure the level of HU increase from baseline on time-attenuation curves (TAC). Recanalization was assessed on follow-up vascular imaging studies that were obtained within 24 hours after tPA. Modified TICI 2b or 3 was considered successful recanalization. Thrombus length, HUr, collaterals, and minimum increase of HU on TAC (HUmin) were compared between the recanalized and non-recanalized groups.

Results:
Of 57 patients who received tPA therapy, 31 patients (female, 13; mean age, 66.5 years) with occlusions in ICA (n=7), M1 (n=8), M1-M2 (n=6), and M2 (n=10) were only assessed. Thrombus length ranged 3-45 mm (median, 12 mm; IQR, 7). HUr was measured from 1.03 to 1.69 (median, 1.26; IQR, 0.19). Good collaterals were noted in 27 patients. HUmin ranged 3-70 HU (median, 15; IQR, 12), and showed negative correlation with thrombus length (rho=-0.410, P=0.022), but not with HUr. HUmin was significantly higher in the recanalized group (n=19) than the non-recanalized group (mean HUmin 23.79 vs 7.83; P<0.0001) independent of thrombus location. Thrombus length, HUr, or collateral status was not significantly different between the two groups. HUmin > 13 was determined with sensitivity of 89.5%, specificity of 91.7%, and AUC of 0.961 for prediction of recanalization.

Conclusion:
HUmin of thrombus was significantly higher in patients with successful recanalization after tPA therapy.
Abstract TP103: Activation of the Pi3k Pathway Plays Important Roles in Reduction of Cerebral Infarction by Cilnidipine
Authors: Koh Seong-Ho , Son Jeong-Woo , Choi Hojin , Yoo Arum , Park Hyun-Hee , Kim Young-Seo , Lee Kyu-Yong , Lee Young Joo
Published: July 2021

Cerebral infarction causes permanent neuronal loss inducing severe morbidity and mortality. Because hypertension is the main risk factor for cerebral infarction and most patients with hypertension take daily antihypertensive drugs, the neuroprotective effects and mechanisms of anti-hypertensive drugs need to be investigated. Cilnidipine, a long-acting, second-generation 1,4-dihydropyridine inhibitor of both L- and N-type calcium channels, was reported to reduce oxidative stress. In this study, we investigated whether cilnidipine has therapeutic effects in an animal model of cerebral infarction. After determination of the most effective dose of cilnidipine, a total of 128 rats were subjected to middle cerebral artery occlusion (MCAO). Neurobehavioral function test and brain MRI were performed, and rats with similar sized infarcts were randomized to either the cilnidipine group or the control group. Cilnidipine treatment was performed with reperfusion after 2-hr occlusion. Western blots and immunohistochemistry were also performed after 24-hr occlusion. Initial infarct volume on DWI was not different between the cilnidipine group and the control group; however, FLAIR MRI at 24 hr showed significantly reduced infarct volume in the cilnidipine group compared with the control group. Cilnidipine treatment significantly decreased the number of TUNEL-positive cells compared to the control group. Western blot and immunohistochemistry showed increased expression of phosphorylated Akt (Ser473), phosphorylated GSK-3β, and Bcl-2 and decreased expression of Bax and cleaved caspase-3. These results suggest that cilnidipine, which is used for the treatment of hypertension, has neuroprotective effects in the ischemic brain through activation of the PI3K pathway.
Abstract TP107: Inhibition of Ras-related C3 Botulinum Toxin Substrate 1 (rac1) Signaling Worsens Neurite Regeneration After Stroke
Authors: Liu Lin , Yuan Hui , McCullough Louise , Li Jun
Published: July 2021

Neurite plasticity is a critical aspect of functional recovery after stroke. Emerging data suggest that Rac1 plays a central role in neurite regeneration in the injured brain, specifically by stimulating neuronal intrinsic growth and counteracting the growth inhibitory signaling that leads to growth cone collapse. We assessed the hypothesis that Rac1 is an important stimulator of neurite regeneration after stroke.

Transient focal ischemia was induced by middle cerebral artery occlusion for 90 minutes in 7 to 8 week old male wild type mice. A specific Rac1 inhibitor, NSC 23766 (NSC) and a selective inhibitor (IPA 3) of PAK1, a downstream kinase of Rac1, were injected starting 7 days after stroke. Pellet reaching test (success rate) was used to assess the integrity of sensorimotor function.

Treatment with NSC worsened recovery assessed by pellet reaching test from day 14 to day 28 after stroke (Day 28: Vehicle 0.39 ±0.03 vs. NSC 0.18±0.03, n=7-9, p<0.05). It additionally reduced axonal density (neurofilament staining, NFL) in the peri-infarct zone (PIZ) assessed on 28 days after stroke (Vehicle 1.00±0.12 vs. NSC 0.50±0.04, n=4, p<0.05), with no effect on brain cavity size. Treatment with IPA 3 reduced the success rate in the pellet reaching test after ischemia (Day 28: Vehicle 0.40±0.03 vs. IPA 3 0.17 ±0.03, n=7-9, p<0.05) and NFL staining in PIZ 28 days after stroke (Vehicle 1.00±0.07 vs. IPA 3 0.52 ±0.10, n=4, p<0.05). LIM domain Kinase (LIMK1) is a key component of the intrinsic capacity of neurite regeneration. Interestingly, NSC reduced LIMK1 phosphorylation (Vehicle 1.47±0.09 vs. NSC 0.75±0.12, n=4, p<0.05) day 14 after stroke, while it increased levels of glial fibrillary acidic protein (GFAP), a signal of neurite growth inhibition (Day 14: Vehicle 1.00±0.24 vs. NSC 1.66±0.11, n=4, p<0.05).

Conclusions:
Inhibition of Rac1 signaling worsened functional recovery and reduced axonal density. This was associated with decreased activation of intrinsic pro-regenerative molecules and increased growth inhibitory signaling. Our data suggested that Rac1 signaling could enhance neurite regeneration and improve post-stroke functional recovery.
Abstract TP115: Carotid Endarterectomy in Young and Middle Aged Patients
Authors: Arhuidese Isibor J , Obeid Tammam , Nejim Besma , Yin Kanhua , Wang Sophie , Hicks Caitlin , Malas Mahmoud B
Published: July 2021

Introduction:
The increasing prevalence and earlier onset of risk factors has resulted in an expanding population of younger patients undergoing carotid endarterectomy (CEA) in recent times. Outcomes after CEA are largely unreported in these patients. In this study, we evaluate 30-day postoperative outcomes after CEA in an exclusive cohort of young and middle aged patients.

Methods:
We studied all patients aged 64 years and younger, who underwent CEA in the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) from January 2005 to December, 2013. Univariate methods (Chi Square, ttest) were employed to compare patients’ characteristics. Multivariate regression adjusting for patient characteristics was used to identify predictors of adverse outcomes.

Results:
There were 15830 CEA’s performed in this cohort with a mean age of 58 (S.D:5.1) years. The majority of patients were male (59%), Caucasian (85%) and hypertensive (81%). Nearly half (46%) were symptomatic. Overall, 266 (1.7%) patients suffered stroke in the 30 day post-operative period, while mortality and myocardial infarction rates were 0.6% and 0.4% respectively. The significant predictors of stroke or death were female gender (OR: 1.49; 95%CI: 1.15-1.92; p=0.002), symptomatic status (OR: 1.69; 95%CI: 1.30-2.21; p<0.001), previous cardiac intervention (OR: 1.42; 95%CI: 1.04-1.93; p=0.026) and physical dependence (OR: 1.81; 95%CI: 1.16-2.82; p=0.01). The mean length of in-hospital stay was 3 (SD:5.6) days and complications within 30 days of surgery are shown in Table 1.

Conclusions:
Absolute stroke and mortality rates after CEA in young and middle aged patients are not different from those reported in the general population. Stroke and mortality are significantly higher in symptomatic, physically dependent patients and those with prior cardiac intervention. We recommend extra vigilance in the management of these patients in order to improve CEA outcomes.
Abstract TP156: Robot-Guided Ankle and Knee Therapeutic Training Improves Motor Functions in Stroke
Authors: Lee Yunju , Chen Kai , Harvey Richard L , Roth Elliot J , Zhang Li-Qun
Published: July 2021

Introduction:
Stroke survivors develop substantial disability such as weakness, spasticity, increased stiffness, and reduced range of motion in lower limbs, contributing to reduced quality of life. It is important to stretch impaired ankle and knee to increase range of motion and reduce spasticity, and to conduct active movement training to improve balance and locomotion.

Hypothesis:
We addressed the hypotheses that robot-aided ankle and knee training will reduce motor impairments and improve balance and gait functions, and the improvements will maintain to the 6-weeks follow-up.

Methods:
Seven male stroke survivors participated in the robot-guided ankle and knee rehabilitation training using a pair of ankle and knee rehabilitation robots over 18 training sessions (3 sessions/week for 6 weeks). Three evaluations were done before and after training, and 6 weeks follow-up. Each session involved passive stretching under intelligent control and active movement training under real-time, audiovisual and haptic feedback. About equal time was spent on the ankle and knee training.

Results:
We found significant improvement in 6-Minute Walk Test (6MWT: 294.8 m pre-training to 386.4 m post training; p<0.01), Berg Balance Scale (BBS, 45 pre to 52 post; p<0.05), ankle active range of motion (AROM) (-11.7° pre to 1.7° post; p<0.05, a negative value means not being able to reach 0° dorsiflexion), passive ROM in dorsiflexion (12.7° pre to 23.3° post; p<0.01), and dorsiflexion muscle strength (-0.3 Nm pre to 5.7 Nm post; p<0.05, negative means lower than the passive torque at 0° ankle dorsiflexion). The knee had significant improvement in AROM in extension against the load of the robot (34.8° pre to 15.9° knee flexion post; p<0.05) and maximal flexion strength at 90° knee flexion (19.3 Nm pre to 31.7 Nm post; p<0.01). At the follow-up, the outcomes were found as similar results of post evaluation, e.g., 379m (p<0.05) in 6MWT, 51 (p<0.05) in BBS, and 5.2 Nm (p=0.05) in dorsiflexion strength.

Conclusions:
In conclusions, robot-guided stretching and active movement training reduced impairments at the knee and ankle of stroke survivors resulting in improved mobility. Furthermore, the effect of training was maintained at the 6-weeks follow-up after the treatment.
Abstract TP165: Cardiac Screening Does not Improve One-year Mortality Among Patients With Cerebrovascular Disease
Authors: Sico Jason J , Baye Fitsum , Myers Laura J , Concato John , Williams Linda S , Bravata Dawn M
Published: July 2021

Introduction:
Guidelines recommend the use of cardiac stress testing to screen for occult coronary heart disease (CHD) among patients with ischemic stroke/TIA who have a ‘high risk’ Framingham Cardiac Risk score (FCRS). It is unclear whether implementation of this guideline confers a mortality benefit among patients with cerebrovascular disease.

Hypothesis:
We assessed the hypothesis that cardiac stress testing would be associated with lower odds of one-year all-cause mortality.

Methods:
Administrative data from a sample of 11,306 Veterans admitted to 134 Veterans Health Administration (VHA) facilities with a stroke or TIA in fiscal year 2011 were analyzed. Patients were excluded (n=6915) on the basis of: prior CHD history, receipt of cardiac stress testing within 18-months prior to cerebrovascular event, death within 90 days of discharge, being discharged to hospice, transferred to a non-VHA acute care facility, or missing/unknown race. A FCRS was calculated for each patient; a score of ≥ 20% was classified as ‘high risk’ of having CHD. Administrative data were used to identify whether cardiac stress testing was performed within 90-days after the cerebrovascular event. Logistic regression was used to assess whether cardiac stress testing was associated with one-year all-cause mortality.

Results:
Of the 4391 eligible patients, 62.8% (2759) had FCRS ≥ 20%, with 4.5% (n=123) of these patients receiving cardiac stress testing within 90 days of discharge. After adjusting for sociodemographic characteristics and medical comorbidities, FCRS ≥ 20% was associated with one-year mortality (aOR=2.18; CI
95
:1.59, 3.00), however, receipt of stress testing was not (aOR=0.59; CI
95
:0.26, 1.30).

Conclusion:
Cardiac screening did not confer a one-year all-cause mortality benefit among patients with cerebrovascular disease. Additional work is needed to assess outcomes among patients with cerebrovascular disease who are at ‘high risk’ for CHD.
Abstract TP17: Uric Acid Consumption in the Patients Receiving Intraarterial Thrombectomy
Authors: Kim Do Yeon , Kim Chi Kyung , Kim Jun Yup , Jeong Han-Gil , Kang Dong-Wan , Pyun Jung Min , Lee Seung-Hoon
Published: July 2021

Background:
Previous clinical studies indicated that serum uric acid (UA) level was correlated with better neurologic outcome, and UA might work as an antioxidant against reactive oxygen species, especially in ischemic-reperfusion injury.

Hypothesis:
If UA has a neuroprotective function against ischemic-reperfusion injury, serum UA will be recruited and the level will be lowered during the period of acute ischemic stroke after intra-arterial (IA) thrombectomy.

Methods:
Among a total of 251 patients who received IA thrombectomy in our hospital from 2005 March to 2015 Aug, we selected the study population according to the following inclusion criteria (N=140): (1) UA level measured within one week after IA thrombectomy; (2) Thrombolysis in Cerebral Infarction perfusion grade (TICI)>0; (3) no recurrence or no severe morbidity or mortality during the acute period. Neurologic severity was assessed via National Institute of Health Stroke Scale (NIHSS), modified Rankin Scale (mRS). The improvement of outcome during admission is assessed via the difference between discharge and admission NIHSS (dNIHSS) scores, and mRS (dmRS) scores. UA consumption ratio was calculated as [(log value of initial serum UA level)- (follow up UA level within 1 week)] / (log value of initial serum UA level).

Results:
UA consumption ratio was significantly correlated with discharge mRS in linear regression analysis (R
2
=0.122,
p
<0.001). In terms of outcome improvement, UA consumption ratio was also correlated with dmRS (R
2
=0.033,
p
=0.03), and dNIHSS (R
2
=0.08,
p
=0.0005). When we classified the UA consumption ratio as quintiles, mRS scores at discharge were lower in the highest quintile (OR=0.26,
p
=0.002), and in the second highest quintile (OR=0.33,
p
=0.01), than in the lowest quintile. In addition, calculated vessel occlusion time (from admission to hospital and completion of recanalization) was positively correlated with UA consumption ratio(R
2
=0.05,
p
=0.04) in patients with outcome improvement (dmRS>0).

Conclusions:
In summary, this study showed that UA consumption was associated with better neurologic outcome and also with the vessel occlusion time. These results suggest that serum UA might be used as an endogenous neuroprotective source against ischemia-reperfusion injury.
Abstract TP176: Stroke Recurrence Among South Asians With diabetes in Ontario, Canada
Authors: Dhamoon Mandip S , Zhou Limei , Stamplecoski Melissa , Kapral Moira K , Shah Baiju R
Published: July 2021

Introduction:
South Asians have earlier cardiovascular disease onset and higher stroke mortality than non-South Asians, but disparities in long-term outcomes after stroke in patients with diabetes are not well described. We compared risk of cardiovascular outcomes after first ischemic stroke between South Asian and non-South Asian patients with diabetes.

Hypothesis:
We hypothesized that South Asian stroke patients with diabetes were younger and had higher stroke recurrence, even accounting for competing risk of death.

Methods:
Using population-based health care databases in Ontario, Canada, we selected all patients with diabetes hospitalized with first ischemic stroke between April 1, 2002 and March 31, 2012, and assigned South Asian vs. non-South Asian ethnicity using a validated surname algorithm. Kaplan-Meier survival analysis and competing risk models estimated risk of death, stroke, and myocardial infarction. The primary predictor was ethnicity; models were adjusted for demographics and vascular risk factors. Sensitivity analysis including adjustment for medication use was performed in those aged >=65 years.

Results:
There were 25495 diabetics with first ischemic stroke; 840 were South Asian and were younger, more often male, had lower income, and had shorter Ontario residency compared to non-South Asians. South Asians had higher incidence and cumulative risk of recurrent stroke (Figure). In adjusted competing risk models, recurrent stroke risk was increased among South Asians compared to non-South Asians (HR 1.17 [95% CI 1.00-1.38]) in the whole cohort and in those aged >=65 years, both with adjustment for medication use (HR 1.23 [1.01-1.50]) and without (1.27 [1.04-1.54]).

Conclusions:
In this large population-based study, South Asian stroke patients with diabetes had higher recurrent stroke risk compared to non-South Asians, despite younger age. Further research and targeted interventions are needed to reduce stroke burden in South Asians.
Abstract TP192: Ability of the Khorana Score to Predict Recurrent Thromboembolism in Cancer Patients With Ischemic Stroke
Authors: Bobrow Dylan , Cushman Mary , Kamel Hooman , Merkler Alexander E , Elkind Mitchell S , DeAngelis Lisa M , Navi Babak B
Published: July 2021

Introduction:
Cancer patients who develop acute ischemic stroke (AIS) are at high risk for recurrent thromboembolism. No risk stratification model exists to predict recurrent events in this population. The Khorana score is a validated risk score for predicting venous thromboembolism in newly diagnosed cancer patients.

Hypothesis:
The Khorana score can effectively classify the risk of recurrent thromboembolism (RTE) in cancer patients with AIS.

Methods:
We retrospectively identified all adults with active systemic cancer diagnosed with AIS by MRI at a tertiary-care cancer center from 2005 through 2009. Two neurologists independently reviewed all available medical records through July 31, 2012. The Khorana score at the time of index stroke was calculated for each patient. Points were assigned for specific cancer sites (2 points for very high-risk sites: stomach or pancreas; 1 point for high-risk sites: lung, lymphoma, gynecologic, bladder, testicular, or renal), platelet count ≥350,000/mcL, hemoglobin <10 g/dl, leukocyte count ≥11,000/mcL, and BMI ≥35 kg/m2. The primary outcome was a composite of RTE, defined as recurrent AIS, TIA, MI, systemic embolism, DVT, or PE. Logistic regression was used to evaluate the association between individual components of the Khorana score and RTE. The c-statistic was used to calculate the discriminatory ability of the Khorana score in predicting RTE.

Results:
Among 263 study patients, 90 (34%) were diagnosed with RTE, including 36 (14%) with recurrent AIS. The median Khorana score was 2 (IQR 1-2, range 0-5). None of the individual components of the score were independently associated with RTE, although there was a nonsignificant trend for high-risk cancer sites (OR 1.56, 95% CI 0.88-2.77). The rate of RTE was 28% among patients with a score of 0, 36% among patients with a score of 1-2, and 32% among patients with a score of 3-6. The c-statistic was 0.52 (95% CI 0.45-0.58) for predicting RTE and 0.49 (95% CI 0.38-0.59) for predicting recurrent AIS.

Discussion:
The Khorana score has poor discriminatory ability for predicting RTE in cancer patients with AIS, probably because these patients represent an especially high-risk group. Future research is needed to identify better methods for predicting RTE in this high-risk population.
Abstract TP20: Prediction of Hemorrhagic Transformation After Endovascular Thrombectomy by Cerebral Blood Volume and Time to Reperfusion
Authors: Yoshie Tomohide , Ueda Toshihiro , Takada Tatsuro , Nogoshi Shinji , Takaishi Satoshi , Fukano Takayuki , Tokuura Daiki
Published: July 2021

Introduction:
Previous studies suggested that low cerebral blood volume (CBV) lesion predicts hemorrhagic transformation after endovascular therapy.

Hypothesis:
We assessed the hypothesis that delays in time to reperfusion lead to hemorrhagic transformation on T2*-weighted MRI after endovascular therapy in patients with low CBV obtained from pre-treatment CT perfusion (CTP).

Methods:
We retrospectively analyzed 62 consecutive patients with acute ischemic stroke who were obtained successful reperfusion (TICI 2A-3) by endovascular thrombectomy for internal carotid artery or M1 occlusion. CTP maps were assessed for relative CBV (rCBV) values obtained separately for cortical and basal ganglia regions in the MCA territory. The presence of cortical and basal ganglia hemorrhage (either HI or PH) was assessed on T2*-weighted MRI after endovascular therapy. We analyzed the influence of rCBV in each region, CTP-to-reperfusion time and degree of reperfusion on cortical and basal ganglia hemorrhage.

Results:
Forty patients developed hemorrhagic transformation. HIs occurred in 16, PH1s in 21, PH2s in 3 and symptomatic hemorrhage in 1 of the patients. rCBV of the cortical region (0.77 versus 0.98, P=0.002) and basal ganglia region (0.64 versus 0.88, P<0.001) were significantly lower in the patients with hemorrhage than in those without. There was no significant difference in CTP-to-reperfusion time between cortical hemorrhage and no cortical hemorrhage groups. However, in the patients with low cortical rCBV (rCBV <0.8) and TICI ≥2b, mean CTP-to-reperfusion time was significantly shorter (70 versus 108 minutes, p=0.021) in the non-cortical hemorrhage group. There was no significant difference in CTP-to-reperfusion time between basal ganglia hemorrhage and non-basal ganglia hemorrhage groups.

Conclusions:
Early reperfusion decreases risk of cortical hemorrhage in patients with low cortical rCBV. Low rCBV in basal ganglia region is more predictive of basal ganglia hemorrhage than time to reperfusion.
Abstract TP200: Family History and Risk of Recurrent Stroke
Authors: Kim Jun Yup , Chung Jong-Won , Kim Beom Joon , Han Moon-Ku , Kang Kyusik , Park Jong-Moo , Park Sang-Soon , Park Tai Hwan , Cho Yong-Jin , Hong Keun-Sik , Lee Kyung Bok , Ko Youngchai , Lee SooJoo , Kim Dae-Hyun , Nah Hyun-Wook , Cha Jae-Kwan , Oh Mi-Sun , Yu Kyung-Ho , Lee Byung-Chul , Jang Myung Suk , Lee Ji Sung , Lee Juneyoung , Bae Hee-Joon
Published: July 2021

Background:
Association between family history of stroke and stroke recurrence remains unclear.

Methods:
Using a web-based multicenter stroke registry database, information on history of stroke in first-degree relatives was collected prospectively in ischemic stroke patients hospitalized within 7 day of onset. Collected information was categorized as follows: type of affected relatives with stroke (paternal, maternal, sibling, or two or more) and age of relative’s stroke onset in relative (< 50, 50∼59, 60∼69, and ≥ 70). Stroke recurrence was captured prospectively using predetermined protocol. Subgroup analysis was performed using categories based on patient’s age at the index stroke.

Results:
Among 7,642 patients, 937 (12.3%) had history of stroke in their first-degree relatives, and 475(6.2%) experienced stroke recurrence (median follow-up, 365 days). In multivariate Cox proportional hazard models, overall family history was not associated with stroke recurrence (hazard ratio [HR], 1.06; 95% confidence interval [CI], 0.80-1.41). However, the details of family history, including relative’s age at stroke onset < 50 (HR, 2.15; 95% CI, 1.01-4.57) and stroke history in sibling (HR, 1.67; 95% CI, 1.09-2.57) were independently associated with stroke recurrence after adjusting for possible confounders. The associations seemed to be stronger in stroke of young adults (age, <55) compared to older stroke patients.

Conclusion:
This study suggests that having relative with early onset stroke and sibling with history of stroke increase the risk of recurrent stroke and imply that additional precautions may be needed in such population.
Abstract TP207: Pre-stroke Dementia is Associated With Poor Functional Outcome After Acute Ischemic Stroke: The Fukuoka Stroke Registry
Authors: Wakisaka Yoshinobu , Matsuo Ryu , Hata Junya , Kuroda Junya , Ago Tetsuro , Kamouchi Masahiro , Kitazono Takanari ,   Fukuoka Stroke Registry Investigators
Published: July 2021

Introduction:
With an aging population, an increased number of acute stroke patients with pre-stroke dementia is expected. Although both stroke and dementia are major cause of disability, the effect of pre-stroke dementia on functional outcome after stroke has been still on debate.

Hypothesis:
Pre-stroke dementia is associated with poor functional outcome after acute ischemic stroke.

Methods:
Of 9198 stroke patients registered in the Fukuoka Stroke Registry in Japan from June 2007 to May 2014, 3843 patients with first-ever ischemic stroke within 24h of onset, who had been functionally independent before the onset, were enrolled in this study (cardioembolism [n=926], large artery atherosclerosis [n=583], small vessel occlusion [n=1045], others [n=1289]). Pre-stroke dementia was defined as any type of dementia that was present prior to the stroke. For propensity score (PS)-matched analysis, 320 pairs of patients with and without pre-stroke dementia were also selected. Study outcome was poor functional outcome (modified Rankin Scale 3-6) at discharge.

Results:
In the total cohort, 330 (8.6%) had pre-stroke dementia. The age (80±8 vs 69±13, year, mean±SD, p<0.01), frequencies of female (46 vs 36, %, p<0.01) and cardioembolism (41 vs 23, %, p<0.01), and NIHSS score on admission (6 [3 - 12] vs 3 [1 - 6], median [interquartile], p<0.01) were higher in patients with pre-stroke dementia than those without the dementia. Poor functional outcome (62 vs 25, %, p<0.01) were more prevalent in patients with pre-stroke dementia than those without the dementia. Multivariable-adjusted analysis showed that pre-stroke dementia was significantly associated with increased risk for poor functional outcome (OR 2.3, 95% CI 1.7-3.2). There were no interactions between pre-stroke dementia and 4 variables (age, sex, stroke subtype, and initial stroke severity [NIHSS≤7 or NIHSS≥8]). In the PS-matched analysis, pre-stroke dementia was still associated with poor functional outcome (OR 4.3, 95%CI 2.1-8.8).

Conclusions:
Pre-stroke dementia was significantly associated with poor functional outcome at discharge in patients with acute ischemic stroke.
Abstract TP222: Frequency of Intracranial Arterial Imaging and its Yield in Consecutive Patients with Non-lacunar Cryptogenic Ischemic Stroke: ESUS Global Registry
Authors: Perera Kanjana S , Swaminathan Balakumar , Bosch Jackie , Hart Robert G ,   on behalf of ESUS Global Registry Investigators
Published: July 2021

Background:
Atherosclerotic stenosis of large IC arteries is an important cause of stroke. The prevalence of ICS in stroke population differs by ethnicity.We report the frequency of ICS among a global sample of patients with non-lacunar cryptogenic ischemic stroke (NLCIS) who did not have another identifiable cause for stroke i.e. cardioembolic, extracranial LAD, or other specific causes.

Hypothesis:
We hypothesized that the prevalence rates of ICS will differ according to global regions.

Methods:
Consecutive patients with recent ischemic stroke were retrospectively surveyed at 19 stroke centers in 19 countries to identify the frequency of IC imaging and its yield. Countries were grouped by World Bank regions. ICS was considered to be significant if there was >50% stenosis in the arteries proximal to the index stroke evidenced by MRA, CTA or TCD.

Results:
We identified a total of 2145 consecutive ischemic stroke patients among which 475 had NLCIS. IC arterial imaging was carried-out,on average, in 87% of patients. Of these 414 patients, 15% had stenosis proximal to the area of brain ischemia. The frequency of ICS among NLCIS patients was highest in East Asia (27%) and lowest in Pacific (4%). Patients with ICS in Latin America were significantly younger when compared to other 4 regions.

Conclusion:
IC arterial imaging is carried out in majority of stroke centers in patients with NLCIS, among whom the fraction of IS associated with ICS is substantial throughout the world, averaging about 15%. MRA / CTA had a higher yield than TCD. On average these patients have traditional vascular risk factors except for Latin American patients who are significantly younger with no vascular risk factors.
Abstract TP228: TCD Preferred as the Screening Test for Right to Left Shunt in Cryptogenic Stroke
Authors: Le Duy , Schlick Konrad , Song Shlee , Rinsky Brenda , Nezhad Mani , Lyden Patrick
Published: July 2021

Introduction:
In patients with cryptogenic strokes, the discovery of a right to left shunt (RLS) may change management. Recent data suggest that transcranial doppler with agitated saline bubble study (TCD) has a higher sensitivity in RLS detection than transesophageal echo (TEE). We evaluated whether or not TCD could guide optimization of stroke care as indicated by a change in stroke management.

Methods:
We reviewed 370 inpatient and outpatient TCD studies performed at Cedars-Sinai Medical Center between May 2013 and May 2015. We recorded TCD, TEE and neurology consult results. Spencer grade (both at rest and with Valsalva) and change in management were determined. A change in management was classified as a change in medication, additional diagnostic testing ordered, or consideration of PFO closure.

Results:
We found 42 patients with both TEE and TCD. Patients were negative for shunt on both TEE and TCD (13); positive both on TEE and TCD (15); positive for right-to-left shunt on TEE and negative on TCD (1); and negative on TEE, but positive on TCD (13).

Average age was 46.2 years, ranging from 28 to 67 years. Seven of 13 patients had a change in management after discovery of the RLS on TCD: 4 PFO closure through trial enrollment; 2 initiated on anticoagulation; 1 hypercoagulable work up. Of the 6 patients without change in management, all had a Spencer grade of 2 or less.

Conclusion:
TCD is a sensitive and reliable, non-invasive study to detect RLS. The ability to perform a Valsalva maneuver accounts for a higher sensitivity for RLS detection. Given the superior sensitivity over TEE and potential to change management, TCD should be the preferred screening test for RLS in cryptogenic stroke patients.
Abstract TP231: Echocardiographically Identified Left Atrial Enlargement is Associated With Non-valvular Paroxysmal Atrial Fibrillation (PAF) and is a Surrogate for PAF Associated Risk for Embolic Stroke
Authors: Molajo Adeniyi O
Published: July 2021

Introduction:
Paroxysmal atrial fibrillation (PAF) and persistent atrial fibrillation are risk factors for systemic embolism including stroke. Both are indication for anticoagulation. Many patients with stroke in sinus rhythm are shown on ambulatory ECG monitoring to have PAF. PAF is difficult to diagnose on ambulatory ECG monitoring. A persistent marker for PAF will be useful to identify need for anticoagulant to reduce stroke risk due to PAF. Echocardiographic variable with a high predictive value for PAF is desirable.

Objective:
The purpose of the study was to investigate the relationship between left atrial (LA) size and proneness to paroxysmal atrial fibrillation and assess its reliability as a surrogate for diagnosing non valvular PAF.

Method:
Echo Database for patients with measured LA volume index, in sinus rhythm without history of intervention for atrial fibrillation, pharmacological therapy, and cardioversion or ablation therapy over a seven year period was reviewed. Patients with enlarged LA Volume index (>28ml/M
2
) were selected. Seven Day ambulatory ECG monitoring was performed in these patients, ResultEchocardiogram data of 245 patients were available for analysis. 41 had greater than mild mitral valve regurgitation and were excluded from further analysis. Age range was 37-93. 99 were male. 211 patients had LA volume index data available. In 8 patients in sinus rhythm on ambulatory ECG, LA volume index was mildly increased (28-34 ml/M
2)
In 16 patients with PAF on ambulatory ECG, LA volume index was mildly increased (28-34 ml/M
2
) In 100 patients with PAF on ambulatory ECG, LA volume index was moderately increased (35-40 ml/M
2
) In 88 patients with PAF on ambulatory ECG, LA volume index was severely increased (>40 ml/M
2
)

Conclusion:
In patients with moderately and severely enlarged LA volume index, there was a high prevalence of paroxysmal atrial fibrillation on ambulatory ECG monitoring. Left Atrial volume index could serve as an echocardiographic surrogate for PAF and identify indication for anticoagulation to reduce stroke risk. It Is More Easily Identifiable Surrogate For PAF Than Ambulatory ECG Monitoring In Stroke Risk Assessment.
Abstract TP233: Are Baseline Characteristics of Stroke Patients Included Into an Observational Study Similar to Patients Included Into a Randomised Controlled Trial?
Authors: Schulte Anna , Jürries Falko , Messerschmid Anna , Behnke Nico , Liman Jan , Wasser Katrin , Gröschel Klaus , Weber-Krüger Mark , Wachter Rolf
Published: July 2021

Introduction:
Undiagnosed atrial fibrillation (UAF) is a major burden in ischemic stroke. However, randomised trials have partly shown astonishingly low AF detection rates (e. g. in the CRYSTAL-AF study). This may be due to differences in baseline and stroke characteristics between studies.

Hypothesis:
We hypothesized that stroke patients in a randomised controlled trial have less severe strokes than patients in an observational trial with similar inclusion and exclusion criteria.

Methods:
We used data from the Find-AF observational (NCT 01855035) and the Find-AF randomised controlled trial (ISRCTN 46104198). We included only patients at study site Goettingen of the Find-AF randomised controlled trial (n=153) and only included patients from the Find-AF observational trial that fulfilled the inclusion/exclusion criteria of Find-AF randomised (n=90). We compared baseline characteristics of screened versus included patients in Find-AF randomised and baseline characteristics and stroke severity parameters between both studies. Data are shown as mean (Standard Deviation) or Median (25%; 75% percentile) and were compared by chi-square, t-test or Mann-Whitney U test.

Results:
Table 1 shows as comparison between baseline characteristics of both studies Comparing patients fulfilling the inclusion/exclusion criteria of Find-AF randomised, but unwilling to give informed consent to randomised patients showed a significant difference in age (77 ± 11 vs. 74 ± 8; p< 0.001), but no difference in gender (p=0.581).

Conclusions:
Both studies included patients similar in age, gender and many comorbidities. Major differences occurred in NIHSS and MRS. As NIHSS is a predictor of atrial fibrillation, randomized controlled trials investigating AF detection should include a minimum NIHSS to avoid a selection bias towards less severe strokes.