bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract TP341: Nursing Impact on the Acute Stroke Team - Driving Practice in a Collaborative Environment
Authors: Speirs Lauri
Published: July 2021

Background /Purpose:
In 2005 a community hospital began the journey to Primary Stroke Center. One aspect was to develop a stroke response team. The acute stroke team must provide neurologist expertise at bedside, be cost neutral, compliment the workflow in the Emergency Department, and maximize the limited number of neurologists on staff. Stroke unit nurses were identified as neurological experts in the hospital. After intense training, Stroke Alert went live in October of 2007. The nurse led acute stroke team (AST) collaborated with the medical staff to increase the total volume of stroke patients receiving t-PA. With additional training, the nurse led team assisted in the identification and transfer of patients for endovascular therapy.

Method:
A group of 12 nurses were trained by the stroke medical director to complete a stroke assessment, then to communicate those findings to the neurologist on call and the Emergency Department physicians. The nurse responders and the Emergency Department nurses were trained to mix and calculate the doses for t-PA. In 2010 the nurse responders were educated on the criteria for endovascular therapy, including time frames, patient assessment, and key CT results. In 2011, the nurse responders were re-educated on the golden hour of stroke.

Results:
Since 2008, over 450 stroke alerts have been activated each year. The administration of t-PA increased from 4 patients in 2007 to 43 patients in 2011; an additional 9 patients were sent to another facility for endovascular therapy. In the first 6 months of 2012, over 50% of patients receive t-PA in less than 60 minutes and Gold plus from the AHA was achieved.

Conclusion:
Nurses can be a vital asset to the AST by providing neurological expertise, collaborating with physicians, and driving the stroke protocols.
Abstract TP387: Abcd
2
Score Predicts The Long-term Risk Of Stroke After Transient Ischemic Attack: Fukuoka Stroke Registry
Authors: Kumai Yasuhiro , Kiyohara Takuya , Kamouchi Masahiro , Yoshimura Sohei , Sugimori Hiroshi , Ago Tetsuro , Shoji Yoshihiro , Ishikawa Eiichi , Santa Naohiko , Irie Katsumi , Kitazono Takanari
Published: July 2021

Background and Purpose—
ABCD
2
score has been developed to predict the early risk of stroke after transient ischemic attack (TIA). The aim of this study was to clarify whether ABCD
2
score predicts the occurrence of stroke in the long term after TIA.

Methods—
Fukuoka Stroke Registry (FSR) is a multicenter epidemiological study database on acute stoke. From June 2007 to June 2011, 496 (305 males, 70 ± 13 years of age) patients who had suffered from TIA and were hospitalized in the 7 stroke centers within 7 days after the onset of TIA were enrolled in this study. The patients were divided into three groups according to the risk: low-risk (ABCD
2
score 0-3; n=72), moderate-risk (4-5; n=229) and high-risk group (6-7; n=195). They were followed up prospectively for up to 3 years. Cox proportional hazard regression model was used to elucidate whether ABCD
2
score was a predictor for stroke after TIA after adjusting for confounding factors.

Results—
Among three groups, there were significant differences in age, hypertension, diabetes mellitus and the decrease in estimated glomerular filtration rate (P<0.01, significantly). During a mean follow-up of 1.3 years, Kaplan-Meier analysis demonstrated that the stroke rate in TIA patients was significantly lower in low-risk group than in moderate-risk or high-risk group (log rank test, p<0.001). The adjusted hazard ratios for stroke in patients with TIA increased with moderate-risk group (Hazard ratio [HR]: 3.47, 95% CI: 1.03-21.66, P<0.05) and high-risk group (HR: 4.46, 95% CI: 1.31-27.85, P<0.05), compared to low-risk group.

Conclusions—
The ABCD
2
score is able to predict the long-term risk of stroke after TIA.
Abstract TP4: How Long is Too Long: The Effect of Thrombectomy Procedure Duration on Outcome in Revascularized SWIFT Trial Patients
Authors: Zaidat Osama , Lazzaro Marc A , Brown Scott , Nogueira Raul G , Gupta Rishi , Jovin Tudor , Jovin Tudor , Siddiqui Adnan , Yavagal Dileep , Jahan Reza , Saver Jeffrey ,   For the Swift Investigators
Published: July 2021

Introduction:
Thrombectomy procedure start time to recanalization has been may be an important predictor of clinical outcome following endovascular therapy of acute ischemic stroke (AIS) patients. In this study, we sought to assess the impact of groin puncture time to revascularization (procedure duration) on outcomes in the multicenter, randomized Solitaire FR with the Intention for Thrombectomy (SWIFT) trial.

Methods:
AIS patients enrolled in the SWIFT trial who achieved the primary endpoint of successful recanalization without hemorrhage (SR-sICH) were included. The procedure duration (PD) was defined as time from groin puncture to revascularization. The PD was the main predictor variable. The main outcome variables were the 90 days modified Rankin’s Scale (mRS)≤2; good neurologic outcome (Rankin’s Scale (mRS)≤2 or NIHSS Improvement of≥0), and mortality. Patient demographic, clinical, and angiographic data was reviewed and p-values were calculated using Wilcoxon, linear regression, Cochran Mantel-Haenzsel, or Fischer exact tests.

Results:
A total of 63 patients achieved SR-sICH and were enrolled in this analysis. A trend of lower mortality rate was noted in those with shorter PD (31(20)) vs. 36(16) minutes,p=0.2). Patients with mRS≤2 had a PD mean time of 36(21) vs. 30(17) minutes,p=0.3. No statistical effect was noted when comparing mortality and mRS within the quartiles of PD time (p=0.39 and p=0.41, respectively). No statistical difference in mRS, good neurological outcome, and mortality when PD dichotomizing to≤1 hour (n=59) vs. >1 hour (n=4). A multivariate model for predicting mRS at 90 days which included PD, age, initial NIHSS, atrial fibrillation, gender, initial systolic and diastolic blood pressure, showed no statistical significance of PD (p=0.8).

Conclusions:
Thrombectomy procedure duration, defined as time from groin puncture to revascularization, did not show a relationship with mRS or good neurological outcome in revascularized patients of the SWIFT trial. A trend toward lower mortality was noted in patients who had a shorter PD. Additional larger sample size prospective trials are needed to clarify the role of PD on clinical outcome.
Abstract TP40: Does The Middle Cerebral Artery Territory Have An Anatomically Defined Ischemic Core?
Authors: Chen Yasheng , An Hongyu , Ford Andria L , Goyal Manu , Vo Katie D , Powers William J , Lin Weili , Lee Jin-Moo
Published: July 2021

Background:
In this study, we sought to determine whether an anatomically-defined ischemic core exists in patients with complete MCA territory ischemia; and whether the depth of ischemia, probability of timely reperfusion, or differential tissue vulnerability contributes to its anatomic location.

Methods:
Mean transit time (MTT) and FLAIR maps were obtained from stroke patients at 3.0 (tp1), 6.2 (tp2) hours, and 1 month after onset. 14 patients (11 received IV tPA) with complete MCA ischemia (visually identified using tp1 MTT) were included. MTT prolongation (pMTT) was computed as: MTT- (median MTT of the non-ischemic hemisphere). All images were aligned to the automated anatomic labeling (AAL) atlas using a B-Spline non-linear registration. To merge data with either left or right MCA ischemia, images with R MCA were flipped right to left prior to image registration. Four aggregate maps were generated as: infarct probability (IP=# of patients with infarction/total # of patients); average pMTT; reperfusion probability (RP=# of patients with reperfusion/total # of patients); and IP normalized to the severity of hypoperfusion (vulnerability index=IP/average pMTT). Pearson correlation was performed between IP and pMTT.

Results:
IP in patients with complete MCA ischemia is highest in the putamen, insula and internal capsule (>80%, Fig. A). This region of high IP co-localized to areas of the largest prolonged MTT-deepest ischemia (pMTT>12 sec, Fig B), but did not complement regions of high RP (Fig C). The vulnerability index did not show a “hot-spot” in the high IP regions (Fig. D). Moreover, IP and pMTT were highly correlated (r=0.75).

Conclusions:
The ischemic core for the MCA territory corresponds to regions with greatest pMTT but not to those with low reperfusion probability. Moreover, the relatively uniform vulnerability index suggests that depth of ischemia rather than differential tissue vulnerability accounts for this region having the highest infarct probability.
Abstract TP400: Racial Differences in the Recovery from Ischemic Stroke after tPA.
Authors: Bhattacharya Pratik , Chaturvedi Seemant
Published: July 2021

Racial minorities are at a disadvantage with regards access to acute stroke therapies. We tested the hypothesis that differences between races would result in disparate recovery from ischemic stroke in patients who receive tPA. Data from the Nationwide Inpatient Sample (NIS) for the years 2001 through 2009 were analyzed. The data represents a 20% sample of all inpatient hospitalizations in the United States. Patients discharged with a diagnosis of Ischemic stroke were identified using ICD-9 codes. The code 99.10 was used to identify patients who received tPA. Patients with self reported races: white, black and hispanic who received tPA for ischemic stroke were included. Outcomes of hospitalization including death and discharge destination were assessed. Racial subgroups by age and gender were also analyzed. In the NIS, 15,279 patients received tPA for ischemic stroke between 2001 and 2009. This included 75.3% white, 12.8% black and 6.3% hispanic. In-hospital death rates were not significantly different: 12.8% for white, 10.9% for black and 6.9% for Hispanic; p=0.07. Death rates remained similar even after adjustments for age. In-hospital death was also analyzed in racial subgroups of men, women, young(≤45), middle age (46-70) and elderly(>70); and there was no difference between races. Discharge destination was used as a surrogate for recovery. Blacks and hispanics had about 25% greater odds of being discharged home. However, when adjusted for age, there was no true difference between the races. Considering a home discharge or discharge to a short term rehabilitation facility as a good outcome, blacks were at a significant disadvantage compared to whites; age adjusted OR 0.88(0.80-0.98). This disparity was noted among black men only, and not in black women. As a minority, Hispanic patients had similar rates of home or rehabilitation discharge as whites. In conclusion, in-hospital death rates and the likelihood of home discharge were similar among races. The mechanisms driving disparate access to acute rehabilitation services among black men are probably biological and social. Reasons for differential access to tPA should be explored and addressed, as minorities receiving tPA have similar survival potential and likelihood for home discharge.
Abstract TP417: Minimally-Invasive Video-Assisted Ligation of Left Atrial Appendage in Atrial Fibrillation: Stroke Prevention Strategy
Authors: Ramlawi Basel , Bedeir Kareem , Garcia-Morales Luis , Volpi John , Ramchandani Mahesh , Reardon Michael
Published: July 2021

Background:
Non-valvular atrial fibrillation (AF) is a leading cause of embolic stroke, especially in the elderly population. The vast majority of thrombo-emboli in AF patients originate within the left atrial appendage (LAA). Effective and complete isolation of the LAA has been demonstrated to have a similar stroke-reduction effect as chronic anticoagulation. This study presents our initial experience with a novel minimally-invasive video-assisted (MIVA) thoracoscopic approach to epicardially isolate the LAA using the AtriClip device.

Methods:
Six consecutive AF patients (mean age 73.6 years, 3 of 6 male) with contra-indication to systemic anticoagulation underwent epicardial ligation of LAA using the AtriClip device. Procedure involved two 5mm ports and one 15mm port with application of the device at the base of the LAA under direct visualization. Immediate intra-operative confirmation of LAA isolation via trans-esophageal echocardiography (TEE) was obtained. Anticoagulation was not restarted post-operatively.

Results:
Average procedure length was 43mins and average length of stay was 72hours. All six patients had a non-complicated post-operative course. No stroke, myocardial infarction, renal failure or re-operation was encountered. No transfusions were needed. All patients were extubated in the operating room at conclusion of procedure and were ambulatory on the first postoperative day. 3 of 6 patients experienced excessive pleural drainage lasting 2-4 days postoperatively. TEE confirmation of complete LAA obliteration was achieved in all patients.

Conclusions:
MIVA LAA ligation appears to be a safe, effective and simple procedure to isolate the LAA in AF patients with contra-indication to anticoagulation. A multi-institutional trial to assess the efficacy of MIVA LAA ligation as a stroke prevention strategy is warranted and forthcoming.
Abstract TP421: Cerebral Blood Flow Dynamics and Head-of-Bed Changes in the Setting of Subarachnoid Hemorrhage
Authors: Kung David K , Chalouhi Nohra , Jabbour Pascal M , Dumont Aaron S , Winn H. R , Howard Matthew A , Hasan David
Published: July 2021

Background:
Head-of-bed (HOB) elevation is usually restricted in patients with aneurysmal subarachnoid hemorrhage (SAH). This practice is believed to prevent cerebral hypoperfusion.

Objective:
The goal of this study is to correlate HOB changes (0
o
and 90
o
) with cerebral blood flow using Trans-cranial Doppler (TCD) and thermal diffusion probe in SAH patients.

Methods:
Thirteen patients with SAH were prospectively enrolled in the study. Eight patients underwent placement of a thermal diffusion probe for regional CBF measurement in the same setting when placing a ventriculostomy. CBF values were measured by TCD alone (13 subjects) or concurrently with thermal diffusion probe (8 subjects) with the patients in a flat (0
o
) and upright sitting position (90
o
) at day 3, 7, and 10.

Results:
The average increase in blood flow velocity when changing HOB from 0
o
to 90
o
was 7.8% on day 3, 0.1% on day 7, and 13.1% on day 10. The middle cerebral artery had the least changes in velocity compared to the anterior cerebral and the posterior cerebral arteries. The average regional CBF measurement was 22.7 +/- 10.3 ml/100g/min in the supine position and 23.6 +/- 9.1 mg/100g/min in the sitting position. The changes were not statistically significant. No change in clinical exam was appreciated. None of the patients developed clinical cerebral vasospasm.

Conclusion:
Changing HOB position in the setting of SAH did not significantly affect either cerebral blood flow velocity or regional blood flow. This data suggests that early mobilization should be considered given the detrimental effects of prolonged bed rest.
Abstract TP423: Postoperative Hemodynamics is Different between Clipping and Coiling after Aneurismal Subarachnoid Hemorrhage -A Multicenter Prospective Cohort Study -
Authors: Horie Nobutaka , Iwaasa Mitsutoshi , Isotani Eiji , Ishizaka Shunsuke , Inoue Tooru , Nagata Izumi
Published: July 2021

Background and Purpose:
Volume management is critical for the assessment of the vasospasm after aneurismal subarachnoid hemorrhage (SAH). In this study, we investigate the difference in the postoperative systemic hemodynamics between surgical clipping and endovascular coiling.

Methods:
In a multicenter prospective cohort study, multiple hemodynamic parameters were calculated by single indicator transpulmonary thermodilution system (Picco®) from day 1 to 14 in the patients with SAH.

Results:
Two hundred and four patients were enrolled in this study, and 176 patients with ruptured anterior circulation aneurysm were analyzed. Clipping was performed in 155 patients and coiling was performed in 21 patients. The patient characteristics were similar in both groups except higher preoperative grade in coiling than clipping. Regarding hematological parameters, clipping group had higher CRP and lower hemoglobin and hematocrits. Preload and afterload were similar in both groups. Coiling group had significantly less cardiac function index compared with clipping indicating that coiling was preferably selected for severe cases. Interestingly, extravascular lung water index (EVLWI) was significantly higher in clipping than coiling group without elevation of the pulmonary vascular permeability index. Moreover, elevation of Brain Natriuretic Peptide did not affect EVLWI.

Conclusions:
We first show that postoperative hemodynamics is different depending on the treatment option: clipping or coiling after aneurysmal SAH. Clipping can enhances cardiogenic lung edema due to hemodynamic stress rather than coiling. Bedside monitoring with Picco® system is a powerful tool for the volume management of patients with SAH.
Abstract TP428: Microsurgical and Endovascular Treatment of Ruptured Distal Anterior Cerebral Artery Aneurysms
Authors: Park Keun Young , Lee Yoon Ho , Ihm Eun Hyun , Lim Yong Cheol , Chung Joonho , Kwon Young Sub , Kim Yong Bae , Kim Byung Moon , Kim Dong Joon , Lee Jae Whan , Joo Jin Yang , Huh Seung Kon , Kim Dong Ik , Lee Kyu Chang , Park Young Mok
Published: July 2021

Introduction:
Distal anterior cerebral artery (DACA) aneurysms are less common and surgical morbidity has been reported relatively high due to intraoperative rupture and narrow surgical field. Endovascular treatment can be alternative to surgery. This study investigated the efficacy and safety of endovascular coiling for ruptured DACA aneurysms comparing with microsurgical clipping.

Patients and Methods:
Between January 1999 and March 2012, consecutive 94 patients with ruptured DACA aneurysm were treated by surgical clipping (n=52, 55.3%) and endovascular coiling (n=42, 44.7%) in five institutions including only 2 cases of recurrence (2.1%, 1 in clip and 1 in coil). The clinical outcomes of patients and procedure-related complications (intraprocedural rupture and any infarction) were evaluated and compared between two groups.

Results:
There were 38 males and 56 females (mean age; 55.1 years). Initial Hunt-Hess grade was GII in 25 patients (37.2%), GIII in 36 patients (38.3%), GIV in 12 patients (12.8%), and GV in 11 patients (11.7%), which was significantly higher in coil group (2.77 in clip vs 3.26 in coil, p=0.016). Initial CT scanning showed ruptured DACA aneurysm with ICH (n=35; 37.2%) and hydrocephalus (n=25; 26.6%). Maximal diameter of aneurysm was less than 5mm in 36 (38.3%), 5~10mm in 53 (56.4%), and 10mm and more than in 5 (5.3%). Technical success rate was 100% and complete occlusion or neck remnant of aneurysm was achieved in 87 [92.6%, 49 (96.1%) in clip vs 38 (90.5%) in coil, p=0.404] and incomplete in 6 (6.4%). At discharge, favorable outcome (modified GOS; good and fair) was obtained in 70 [77.8%, 44 (84.6%) in clip vs 26 (68.4%) in coil, p=0.078]. Intraprocedural rupture occurred only in clipping group [6 cases (11.5%), p=0.031]. Any procedure-related infarction occurred in 7 [7.4%, 6 (11.5%) in clip vs 1 (2.4%) in coil, p=0.126]. Intraprocedural thrombus was detected in 5 cases of coil group and most of them were restored by thrombolytic therapy. There was one case of acute rebleeding in coiling group and this patient died.

Conclusions:
Endovascular coiling was comparable treatment with clipping for ruptured DACA aneurysms.
Abstract TP434: Regulation of BK Channel ß
1
Subunit Expression by Muscle Ring Finger-1 Protein in Diabetic Vessels
Authors: Lu Tong , Fu Yi , Willis Monte S , Lee Hon-Chi
Published: July 2021

BK channels, abundantly expressed in vascular smooth muscle cells (VSMCs), are the key determinant of vascular physiology. BK channel activity is tightly regulated by its accessory β
1
(BK-β
1
) subunits. BK-β
1
protein expression is down-regulated in diabetic vessels, contributing to diabetic vascular complications including hypertension, stroke and coronary heart disease. However, BK-β
1
mRNA is not reduced in diabetic vessels suggesting increased BK-β
1
turnover. Since ubiquitin-proteasome system (UPS) accounts for 80~90% of intracellular protein degradations in mammalian cells, we hypothesize that muscle ring finger-1 (MuRF-1) protein, the muscle specific E3 ligase, accelerates vascular BK-β
1
degradation in diabetes mellitus. In this study, we found that BK-β
1
protein level was decreased by 1.95±0.14 fold, accompanied by a 2.83±0.16 fold increase of MuRF-1 expression in streptozotocin-induced diabetic mouse vessels (n=3, p<0.05 vs. control). Moreover, response of vascular BK channel activation by DHS-1 (a specific BK-β
1
activator) was absent in diabetic mouse vascular smooth muscle cells (VSMCs). Similar results were observed in human VSMCs cultured with 22 mM glucose (HG) compared to those cultured with 5 mM glucose. Knockdown of MuRF-1 by siRNA (100 nM) produced a 4.2-fold decrease of MuRF-1 protein level and a 1.8-fold increase in BK-β
1
expression in HG-cultured VSMCs. In addition, the total BK-β
1
expression was 2.58±0.04 fold lower but the ubiquitinated BK-β
1
protein was 5.18±0.04 fold higher in HEK293 cells 48-h after transfection with MuRF-1, compared to those with MuRF-1ΔR (an inactive mutant with the Ring structure deletion) transfection (n=3, p<0.05). Immunoprecipitation experiments confirmed that the N-terminus of BK-β
1
was physically associated with MuRF-1. Inhibition of UPS activity by 10 μM MG-132 (a proteasome inhibitor) enhanced BK-β
1
expression by 1.70±0.01 fold (n=3, p<0.05 vs. control). Our results indicate that MuRF-1 participated in ubiquitin-mediated vascular BK-β
1
protein proteasomal degradation and delineated a fundamental mechanism underlying vasculopathy in diabetes.
Abstract TP446: Noninvasive Evaluation of Cerebral Arteriovenous Malformations by 4D-CT Angiography using 320-detector row CT
Authors: Tajiri Hiroyuki , Jin Lee , Tsukiyama Toshitaka , Suzuki Yumiko
Published: July 2021

Background and Purpose:
Patients with higher Spetzler-Martin grade cerebral arteriovenous malformations (AVMs) are associated with poorer neurologic and clinical outcomes. Four dimensional computed tomography angiography (4D-CTA) is newly and promising technique in the diagnosis of patients with cerebral arteriovenous malformations (AVMs). The purpose of this retrospective study was to investigate the utility of 4D-CTA using whole-brain
320-
detector row CT for assessing cerebral AVMs compared with conventional angiography (CA).

Materials & Methods:
Participants comprised patients admitted to our institution from November 2010 to March 2012 due to cerebral AVMs, who underwent both 4D-CTA and CA within 14days. The diagnosis of AVM was finally confirmed by CA. Two readers reviewed 4D-CTA and CA under consensus regarding detection rate of the AVMs, each component of the AVMs (feeders, nidi, drainers) which was scored using four-point grading scale (excellent=3, good=2, fair=1, poor=0), and the Spetzler-Martin (S-M) grade.

Results:
During study periods, eleven patients met our criteria. In every case, cerebral AVM was diagnosed by 4D-CTA. The average score for feeders, nidi, and drainers was 2.0, 2.3, and 2.5 in 4D-CTA and 2.4, 2.6, and 2.7 in CA, respectively. The average score of S-M grade was both 2.0, and matched in 11/11 patients. There were no significant differences statistically between two modalities (P<.005).

Conclusion:
4D-CTA using 320-detector row CT is a very reliable method and offered diagnostic performance equivalent to CA in detecting and predicting S-M classification of cerebral AVMs.
Abstract TP53: Simple And Easy Way Using Time-Intensity Curve of Perfusion-Weighted Images to Find Penumbra In Stroke Patients Within 4.5 Hours Of Onset Due To The Carotid Artery Occlusion
Authors: Mori Takahisa , Iwata Tomonori , Miyazaki Yuichi , Nakazaki Masahito , Takahashi Yoichiro , Mizokami Koji
Published: July 2021

[Purpose]
It is not clear how to find penumbra from MR-PWI for reperfusion therapy (RT). The aim of our retrospective study was to investigate whether or not a simple way using time-intensity curve (TIC) of PWI can find penumbra in stroke patients admitted within 4.5 hours from sudden onset due to acute carotid artery occlusion.

[Subjects and Methods]
Included for analysis were stroke patients 1) who were admitted within 4.5 hours of onset between Jan 2006 and January 2011, 2) who presented NIHSS score of 6 or more on admission, and 3) who underwent emergency MR imaging , which suggested the affected carotid artery occlusion. We assessed, NIHSS on admission (NIH adm), DWI-ASPECT score, TIC types, successful recanalization (SR), NIHSS on the 7th day (NIH 7
th
), and in-hospital death. Early neurological improvement (ENI) was defined as NIH adm - NIH 7
th
>0. TICs were generated on region of interests set at symmetrical positions of the bilateral MCA territories. According to the time to peak (TP) and the peak signal (PS) comparing the affected side (a) with the contralateral side (c), we classified TIC pattern into four types and defined type 1 as TPa>TPc and PSaTPc and PSc/2≦PSaTPc and PSa≧PSc, and type 4 as TPa=TPc. Relationship between TIC types, in-hospital death and ENI were assessed.

[Result]
Eighty-seven patients were analyzed. There were 36, 39, 12 and 0 patients in TIC type 1, 2, 3 and 4, 39 patients (44.8%: 39/87) underwent RT and SR was achieved in 18 patients (46.2%), and 29 patients died. Among variables, TIC type 1 was the only determinant of in-hospital death (p<0.01) and SR coupled with TIC type 2 was the determinant of ENI (p<0.01).

[Conclusion]
TIC type 1 predetermines poor clinical outcome and type 2 means penumbra, where SR may early improve neurological symptoms. TIC is an easy way to find penumbra in an emergency setting.
Abstract TP57: Post-Procedure ASPECTS Score Incorporating Parenchymal Hyperdensity Correlates with Clinical Outcome After Endovascular Therapy
Authors: Rastogi Sachin , Vinuela Fernando , Duckwiler Gary , Jahan Reza , Tateshima Satoshi , Gonzalez Nestor , Saver Jeffery , Liebeskind David S
Published: July 2021

Introduction:
Noncontrast head CT (NCHCT) is routinely acquired after endovascular therapy for acute stroke to evaluate for early complications, yet residual contrast staining is common. We hypothesized that modification of ASPECTS scoring to include any region involved with either abnormal hypodensity or hyperdensity may accurately correlate with subsequent clinical outcomes.

Methods:
Consecutive patients with M1 or M2 MCA occlusion treated over a 2-year period were analyzed. All patients that underwent immediate post-procedure CT and MRI within 24 hours were included. Clinical and radiological data was reviewed. A modified ASPECTS scoring system was applied that considered areas of parenchymal hyperdensity as also being involved by ischemic injury.

Results:
A total of 30 patients were identified, including 14 men and 16 women with an average age of 64.5 years old. Endovascular recanalization procedures were performed with either the MERCI and\or Penumbra devices. Comparison of the modified ASPECTS score on the post-procedure CT with the post procedure ASPECTS score on DWI MRI demonstrated good correlation with no statistically significant difference (p = .260). On the immediate post-procedure CT, patients with a modified ASPECTS score greater than or equal to 7 versus those with a score less than 7 had an average NIHSS reduction at discharge of 7.3 versus 2.2 (p=.014) and 90 day modified Rankin score of 2.3 versus 4.5 (p=.002). Presence of parenchymal hyperdensity versus no hyperdensity on the post-procedure CT alone did not correlate with clinical outcomes using NIHSS or 90 day modified Rankin score (p=.120 and p=.069 respectively).

Conclusions:
Evaluation of the immediate post procedure NCHCT using a modified ASPECTS scoring system, which incorporates any parenchymal hyperdensity, may be useful to judge clinical response to the intervention. Patients with modified ASPECT score greater than or equal to 7 did significantly better than those with lower scores. Presence of parenchymal hyperdensity alone did not correlate with clinical outcomes.
Abstract TP63: High-flow Oxygen Reduces Cerebral Blood Flow
Authors: Mistri Amit K , Syed Nazia , Panerai Ronney B , Robinson Thompson G
Published: July 2021

Background:
Normobaric high-flow oxygen (NBO) is often used in the pre-hospital and emergency setting following acute stroke, extrapolating evidence of benefit following myocardial infarction. However, in the context of impaired cerebral autoregulation following acute stroke, it is important to establish the effect of high-flow oxygen on cerebral blood flow (CBF). A study in healthy volunteers has demonstrated good visit-to-visit reproducibility of transcranial Doppler (TCD)-estimated CBF velocity (CBFV: surrogate for CBF) measurements with NBO - coefficient of variation 3.85%, comparable to previous studies on air.

Methods:
We studied the effect of NBO on CBFV in subjects following TIA, acute stroke, previous stroke and in healthy volunteers. Bilateral CBFV recordings were performed using TCD. Four minute assessments were repeated during inhalation of air and NBO (80% oxygen), in random order. Repeated measures ANOVA was used to analyse difference between air and oxygen.

Results:
33 subjects were recruited (17 volunteers, 7 acute stroke, 5 TIA, 4 previous stroke). Age: mean (SD) 58 (15) years, male 64%. There were no inter-hemispheric differences in CBFV, therefore we averaged values from both hemispheres. Mean (SD) CBFV was 47 (11) on air; 45 (11) on NBO. Mean CBFV was significantly lower during NBO administration, in the whole population (2.1 + 0.6 cm/s, within subjects effect p=0.003). There was no significant between-group interaction (p=0.99).

Discussion:
NBO is associated with a significant fall in CBFV which may be deleterious in the setting of acute stroke. In the absence of any clear benefit, high-flow oxygen should not be used routinely in patients with acute stroke. Further research is required to establish the effects on other cerebral haemodynamic parameters, including autoregulation and cerebrovascular reactivity.
Abstract TP85: Screening Individuals with Intracranial Aneurysms for Abdominal Aortic Aneurysms is Cost-Effective Based on Estimated Co-prevalence
Authors: Ball Benjamin Z , Southerland Andrew M , Stukenborg George J , Luke Sothear H , Upchurch Gilbert R , Meschia James F , Worrall Bradford B
Published: July 2021

Introduction:
Abdominal aortic aneurysm (AAA) rupture is associated with high mortality and morbidity. The U.S. Preventive Services Task Force recommends one-time ultrasound screening for AAA in men age 65-75 who have ever smoked. Little is known about other high-risk subpopulations. Recent linkage and genome-wide association studies confirm a shared genetic risk between AAA and intracranial aneurysms (IA). We tested the hypothesis that sonographic screening for AAA in individuals known to have IA is cost-effective.

Methods:
A decision tree model was developed to compare costs and outcomes of AAA screening compared to no screening in a hypothetical cohort of patients with IA. Event probabilities, utilities, and costs included in the model were derived through a comprehensive literature review. Expected outcomes of screening vs. no screening were measured in terms of quality-adjusted life years (QALY), lifetime costs and the overall cost-effectiveness ratio. Sensitivity analyses were performed to assess the effects of ranging baseline variables, within plausible minimum and maximum values, on model outcomes, as well as to identify thresholds of model variables where a decision alternative was dominated (both more expensive and less effective than the alternative).

Results:
In our base-case analysis, screening for AAA provided an additional 0.1055 QALYs (28.1521-screening, 28.0466-no screening) at an additional lifetime cost of $3.62 ($374.57-screening and $370.95-no screening). This yielded an incremental cost-effectiveness ratio (ICER) of $34.31/QALY. In sensitivity analyses, a prevalence of AAA in the IA population ≥ 7.5%, sensitivity of ultrasound screening ≥ 91%, or extrapolating the risk of AAA rupture to 6 years each caused the screening arm to dominate the model.

Conclusion:
Based on this model, screening for AAA in individuals with IA is cost-effective with an ICER of $34.31/QALY. This is well below accepted societal thresholds estimated to be less than $50,000/QALY. The sensitive variables in the model, particularly co-prevalence of IA and AAA, favored screening within conservative estimates from the literature. Prospective study evaluating the co-prevalence of IA and AAA will further elucidate the value of dedicated screening.
Abstract WMP1: DWI ASPECT Scores And Infarct Volume As Predictors Of Outcome After Recanalization In Middle Cerebral Artery Stroke
Authors: Nanduri Sunanda , Jadhav Ashutosh P , Zaidi Syed , Aghaebrahim Amin , Jumaa Mohammad , Hammer Maxim , Reddy Vivek , Linares Guillermo , Jankowitz Brian , Wechsler Lawrence , Jovin Tudor
Published: July 2021

Background and Purpose:
Final infarct volume has previously been shown to be a major predictor of outcome after endovascular therapy for middle cerebral artery (MCA) occlusion. However, the importance of specific location of infarct within the MCA territory has not been described. We sought to assess the predictive value of specific topographic regions as predictors of outcomes in a homogeneous cohort of patients treated with endovascular therapy of M1 occlusive disease who underwent post procedure MRI.

Methods:
A retrospective review of our prospectively maintained single center endovascular database was performed. Automated software was used to measure infarct volume and the DWI ASPECT score was assessed by visual inspection using standard templates. Univariate and multivariate analysis was performed to determine predictors of favorable outcomes using each of the 10 regions as part of the ASPECT score as well as total ASPECT score.

Results:
100 patients were identified. 56% were female. Median age was 70. Successful recanalization was achieved with TIMI 2/3 flow in 87% of patients and TICI 2B/3 in 61% of patients. Good outcomes (mRS 0-2 at 3 months) in 46% of patients. There was no difference between outcomes based on the hemisphere involved. Median final infarct on DWI MRI at 24 hours was 39 cc. Median ASPECT score was 6. In multivariate analysis, strong predictors of good outcomes included: age (OR 0.88, 95% CI 0.8-0.96, p=0.006), serum glucose on admission (OR 0.98, 95% CI 0.97-1, p=0.046) and ASPECT score on MRI (OR 0.7, 95% CI 0.03-1.05, p=0.03). There was a high correlation between the volume of infarct and ASPECT score on the post recanalization MRI (Spearman’s rho of -0.76).

Conclusions:
Quantitative (automated software) and semi-quantitative (ASPECT score values) measurements of infarct size are highly predictive of outcomes after recanalization therapy in middle cerebral artery infarcts. No single topographic region or combination of regions is predictive of outcome, whereas total ASPECT scores are highly predictive. These data support the role of post procedural MRI in guiding prognosis after anterior circulation infarct.
Abstract WMP107: Factors Affecting Time to Achieve Assigned Blood Pressure Targets in the Secondary Prevention of Small Subcortical Strokes (SPS3) Trial
Authors: Szychowski Jeff M , McClure Leslie A , White Carole L , Pergola Pablo E , Benavente Oscar R , Coffey Christopher S
Published: July 2021

INTRODUCTION:
The NIH-funded SPS3 study examined two targets of systolic blood pressure (SBP) control for prevention of recurrent stroke: usual (130-149 mmHg) and intensive (<130 mmHg). Patients were recruited from the United States (US), Canada, Spain, and Latin America (LA). Evaluation of treatment efficacy depends upon the ability to achieve assigned SBP control levels. We examined regional differences and patient characteristics influencing time to achieve target.

METHODS:
Cox proportional hazards models were used to model time to achieve in-target status, defined as two consecutive visits within assigned range. Regional effects were tested along with patient gender, age, medical indications, baseline SBP, and size of recruitment center. Scheduled SBP check attendance, active study participation and compliance status, and number of antihypertensive medications over time were also examined.

RESULTS:
SPS3 recruited 3020 patients and SBP target groups were examined separately. Target was achieved after a median of 3 months in each group. Patients in LA achieved intensive control more quickly than in US (HR=1.45, 95% CI: 1.26-1.68); no regional differences were found for usual group. For intensive group, diabetes, higher baseline SBP and medications were associated with delayed control; large sites with increased control (Table). Male gender, active participation and compliance, and attendance of scheduled visits were associated with increased control in both groups (Table).

CONCLUSIONS:
LA patients achieved intensive control more quickly than US patients but no other regional effects are noted. Adherence to scheduled visits and actively compliant study participation are the greatest indicators of target achievement. These results may aid planning and implementation of future international hypertension trials.
Abstract WMP109: A Third Of Ruptured Aneuryms Are Clipped/coiled Outside High Volume Centers
Authors: Adeoye Opeolu , Herbers Patricia , Abruzzo Todd , Khoury Jane , Khatri Pooja , Ferioli Simona , Kleindorfer Dawn
Published: July 2021

Background:
Recent ASA guidelines for the management of aneurysmal SAH (aSAH) patients recommend that low-volume hospitals (<10 aSAH cases/year) should not perform interventions such as clipping and coiling to secure aneurysms, but instead facilitate early transfer to high-volume (>35 aSAH cases/year) hospitals. Using an administrative database, we sought to determine the hospital-level rates of interventional treatment for aSAH patients compared to annual aSAH patient volume in the United States from 2006 to 2010.

Methods:
This analysis utilized the Premier database, a representative sampling of US hospitals that includes ~15% of hospital discharges. The study period was fiscal years 2006-2010. Cases were defined by primary discharge diagnosis of aSAH (ICD 9 code 430) in patients aged ≥18years. The rates of aneurysmal clipping and coiling were determined by querying the procedure codes 39.51, 39.72, 39.75 and 39.76. The mean annual aSAH volume over the five years by hospital was classified as low (<10), medium (10-35) and high (>35). The Wilcoxon rank sum test was used to test for median differences between groups and chi-square tests for differences in proportion.

Results:
The proportion of aSAH patients hospitalized at low, medium and high volume hospitals during the study period was 20%, 32% and 48%, respectively. Of all 14,065 cases, 2366 (17%) received clipping and 3070 (22%) received coiling. See table for hospital-level rates of intervention stratified by annual aSAH volume.

Conclusion:
While many aSAH patients in the United States were hospitalized at high volume hospitals from 2006 to 2010, 34% of clipping and coiling procedures were performed by low- or medium-volume hospitals. Given reports of improved outcomes at higher volume hospitals, efforts should be aimed at transferring aSAH patients from low volume to higher volume hospitals for clipping and coiling procedures.
Abstract WMP13: The Predictive Value of Volumetric MRI Profiles in Stroke Patients Receiving IV tPA in the 3-Hour Time Window
Authors: Jen Shyian S , Sweeney Elizabeth M , Hillis Argye E , Crainiceanu Ciprian M , Krakauer John W , Barker Peter B , Leigh Richard ,   on behalf of the STIR and VISTA Imaging Investigators
Published: July 2021

Background:
Recent studies have detected a population of acute ischemic stroke patients whose MRI profile is associated with intracranial hemorrhage (ICH) when treated beyond 3 hours. This so-called malignant profile (MP) supports MRI based selection of patients for treatment.

Purpose:
To test the hypothesis that there is an MRI based volumetric profile that identifies patients at increased risk of ICH when treated with IV tPA within 3 hours

Methods:
An analysis was performed on a database of stroke patients provided by the STIR and VISTA Imaging Investigators. 75 patients were identified who had DWI, PWI, and GRE images prior to IV tPA and follow-up imaging to assess for parenchymal hematoma (PH). The pre-tPA MRI scans were analyzed using Matlab software to calculate DWI and PWI volumes. DWI lesions were defined by an ADC threshold of 600. PWI lesions were defined by a time-to-peak threshold of an 8 seconds delay. Follow-up GRE images were reviewed for evidence of PH. ROC curves were generated using thresholds from 1-300mL.

Results:
44 of the 75 patients were women with a mean ± stdev age of 70±17. The mean NIHSS was 12±9. The mean time from stroke onset to tPA administration was 147±30 minutes. For the entire cohort, mean lesion volumes were 22±41mL for DWI and 41±42 mL for PWI. 9 patients developed PH. For the PH group, mean lesion volumes were 24±20 mL for DWI and 48±40 mL for PWI. The ROC curves are shown in Figure 1. The areas under the curves are 0.68 for DWI volumes and 0.60 for PWI volumes. The optimal thresholds for predicting PH were 13 mL for DWI with a sensitivity of 0.67 and a specificity of 0.66 and 21 mL for PWI with a sensitivity of 0.78 and a specificity of 0.46.

Conclusions:
Although DWI volume performed better than PWI volume in predicting PH, neither served as a robust predictor in this population. Although further studies are needed, these results suggest that an MRI profile defined by DWI and PWI volumes in the 0-3 hour window may not be able to reliably guide clinical management.
Abstract WMP25: Single-Center Experience with Dual Antiplatelet Therapy Management in Patients Treated with the Pipeline Embolization Device
Authors: Delgado Almandoz Josser E , Crandall Benjamin M , Scholz Jill M , Fease Jennifer L , Anderson Ruth E , Kadkhodayan Yasha , Tubman David E
Published: July 2021

Purpose:
To determine the number of clopidogrel or prasugrel dose adjustments needed and final DAT regimen used to maintain patients undergoing Pipeline Embolization Device (PED) procedures within a target P2Y12 inhibition range.

Methods:
We recorded the number of clopidogrel or prasugrel dose adjustments, final DAT regimen and thromboembolic and hemorrhagic complications in patients undergoing PED procedures at our institution over an 8-month period. P2Y12 inhibition was measured with VerifyNow 10 and 30 days after dose adjustments (target range 80-200 P2Y12 reaction units). Patients received 325mg aspirin daily.

Results:
Forty-four patients underwent PED procedures at our institution during the study period, 36 female and 8 male, mean age 59 years (median 63 years, range 31-81 years). Thirteen patients did not require dose adjustments to remain within the target P2Y12 inhibition range (30%). Thirty-one patients required dose adjustments to remain within the target P2Y12 inhibition range (70%), with a mean of 2.1 dose adjustments per patient (median 2, range 1-5), and a mean time from initiation of DAT to last dose adjustment of 47.5 days (median 42 days, range 8-149 days). Four patients exceeded the target P2Y12 inhibition range after a dose adjustment (13%, 3 prasugrel, 1 clopidogrel), without complications. The table summarizes the final DAT regimen and associated major thromboembolic and hemorrhagic complications leading to death or a permanent neurological deficit in our cohort. Most major complications (80%) occurred in patients who were outside the target P2Y12 inhibition range shortly before or at the time of the complication.

Conclusion:
The majority of patients undergoing PED procedures in our cohort (70%) required an average of 2 clopidogrel or prasugrel dose adjustments to remain within a target P2Y12 inhibition range. Future research is needed to determine if active management of DAT may decrease the risk of major complications after PED procedures.
Abstract WMP26: Endovascular Arterial Deconstruction with a Combination of Onyx and Coils: Technique, Feasibility, and Complications
Authors: Chalouhi Nohra , Starke Robert M , Tjoumakaris Stavropoula , Jabbour Pascal , Gonzalez L Fernando , Hasan David , Rosenwasser Robert , Dumont Aaron S
Published: July 2021

Object:
Permanent vessel deconstruction has become routine for the management of aneurysms, pseudoaneurysms, tumors, and carotid blowouts. We describe a new technique for carotid and vertebral artery deconstruction using a combination of Onyx and coils, and assess its feasibility, safety, and efficacy.

Methods:
Between 2008 and 2012, a total of 41 patients underwent carotid or vertebral artery deconstruction with a combination of Onyx and coils in our institution. A few coils were initially deployed in the parent vessel under proximal flow arrest followed by Onyx embolization directly into the coil mass.

Results:
A total of 26 internal carotid arteries and 15 vertebral arteries were treated. In all but one patient, a balloon test occlusion was performed prior to permanent arterial occlusion. The mean number of coils used was only 6.8 (range, 2-19). The total volume of Onyx used was 1.3 ml on average (range, 0.2-5.2 ml). All 41 (100%) parent arteries were successfully occluded. No distal migration of Onyx or coils was noted. Periprocedural complications occurred in 14.6% (6/41) of cases causing permanent morbidity in 7.3% (3/41). All were the result of delayed ischemic events after vessel deconstruction; none were related to the occlusion technique. No patient developed a recurrence during the follow-up period (mean, 14 months).

Conclusions:
Parent vessel occlusion with a combination of Onyx and coils is feasible, safe, and effective and results in significant savings in terms of cost, operative time, and fluoroscopy time. Importantly, no complications related to the technique itself were encountered in the series. This new technique should replace the traditional deconstruction technique with coils alone.