bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract WMP40: A Geospatial Information Services Assessment of Prehospital Bypass on Overtriage for Large Vessel Occlusion and Hemorrhagic Stroke
Authors: Asimos Andrew W , Satyanarayana Sagar , Strong Dale , Inman Michael , Rhoten Jeremy , Black Annabelle , Dometrovich Melissa , Studnek Jonathan , Swanson Doug R , McWilliams Laurie , Fillmore Ryan , Karamchandani Rahul
Published: February 2024

Introduction:
To increase the number of patients with large vessel occlusion (LVO) acute ischemic strokes (AIS) transported directly to Comprehensive Stroke Centers (CSCs), on December 1, 2021, the threshold score for our county EMS agency’s quantitative stroke severity scale (FAST-ED) for bypassing a non-CSC decreased from 7 to 6. The goal of this work was to evaluate the impact of and adherence to this change, and its effect on overtriage.

Methods:
Two large regional health systems and the county EMS agency collaborated on this study. Using latitude and longitude coordinates from our EMS agency’s database, we geocoded the pick-up location of all patients who had a FAST-ED score of ≥6 from September 2019 to December 2022. We used ArcGIS to calculate drive times to the closest facility among 2 CSCs and 7 non-CSCs, and linked EMS records to hospital records to determine LVO AIS involving the intracranial ICA, M1, M2 or basilar artery. For patients without a CSC as the closest destination facility, we defined overtriage as routing to a CSC for a non-LVO or non-hemorrhagic stroke patient.

Results:
Over our 40-month study period, among patients with a FAST-ED score performed (n=13,913), 824 had a score ≥6. Actual versus ArcGIS drive times in minutes [mean(SD)] compared favorably [14.8(8.5) vs 14.4(6.4), with an ICC of 0.68 (95% CI 0.64-0.72). For 799/824 patients (97%), one of the county’s two CSCs was not the closest destination facility, and among this group 99% (n=787/799) of EMS records were successfully linked to the hospital record. Among these patients, prior to December 1, 2021, 67% (n=219/326) patients with FAST-ED score ≥7 were bypassed to a CSC, with an overtriage rate of 49% (n=107/219), while after that date 88% (n=230/262) patients with a FAST-ED score ≥6 were bypassed to a CSC, with an overtriage rate of 55% (n=126/230).

Conclusion:
It is feasible to use drive times calculated from ArcGIS to evaluate the performance of EMS stroke triage and destination plans. Lowering our county’s FAST-ED score threshold for bypass increased adherence to the bypass protocol with a modest increase in overtriage. Future work will incorporate undertriage rates with the ultimate goal of optimizing our regional stroke and triage destination plan.
Abstract WMP62: Infarct Core Volume Estimation on Non-Contrast Computed Tomography in Late Window Patients Using a Machine Learning Algorithm Software
Authors: Vivanco-Suarez Juan , Rodriguez-Calienes Aaron , Salvia Victor , Galecio-Castillo Milagros , Lu Yujing , Marti Cristian , García Rey Alba , Jovin Tudor G , Ribo Marc , Ortega-Gutierrez Santiago
Published: February 2024

Introduction:
A simplified patient selection paradigm can reduce time to reperfusion and widen the eligibility of large vessel occlusions (LVO) for endovascular therapy (EVT). We developed and externally validated a machine learning (ML) algorithm to estimate infarct core volume (ICV) on non-contrast computed tomography (NCCT) in anterior circulation LVOs presenting in the late window (≥ 6-24 hours).

Methods:
LVOs from prospective databases in US and Spain were included. For development, 2858 stroke activations with NCCT/CT angiography[s1] were included. For validation, consecutive LVOs with admission NCCT/CT perfusion (CTP), post-EVT diffusion-weighted imaging (DWI) within 24 hours, and mTICI ≥2b were included. Neuroimaging experts adjudicated ASPECTS on NCCT and final infarct volume (FIV) on DWI (ground truth). ML algorithm was trained using UNet architecture with ResNet 34 encoder to identify ICV on NCCT. Estimated ICVs (algorithm, CTP [<30% cerebral blood flow], and ASPECTS) were compared to ground truth using correlations (intraclass correlation coefficient [ICC] and Spearman’s [r
s
]) and Bland Altman plots. Superiority tests between correlations (to compare modalities) and subgroup analyses were performed.

Results:
98 patients (median age, 70 years; IQR:59-80; 51% females) were included for validation. Median time to first imaging was 11.4 hours (IQR:9.0-14.7). Correlations (Table) were moderate with the ML algorithm (ICC:0.59) and poor with ASPECTS (r
s
:-0.31) and CTP ICV (ICC:0.42;). Bland Altman plots showed that ML algorithm had a mean difference closest to zero (-34.2 mL) while the CTP ICV had a larger mean difference (-45.8 mL). Superiority tests (Table), [s2] ML algorithm correlation showed superiority to both the CTP (

p
sup

=.018) and ASPECTS (

p
sup

=.003) correlations.

Conclusion:
On late window patients, estimation of ICV on NCCT with the ML algorithm seems to be superior to CTP and ASPECTS. Further prospective studies are needed.
Abstract WMP66: Detecting Medium Vessel Occlusions and Collateral Assessment With Multimodality AI Approach
Authors: Sowlat Mohammad Mahdi , Zamarud Aroosa , Albers Gregory W , Campbell Bruce , Heit Jeremy J , Spiotta Alejandro M
Published: February 2024

Introduction:
Recent advances and the use of Artificial intelligence (AI) is changing the standards of care in stroke patients. AI software has a high sensitivity and specificity for identifying Large Vessel Occlusions (LVOs), but the accuracy for detecting Medium Vessel Occlusions (MeVOs) is limited. We investigated the performance of the combination of two different AI modules for the identification of MeVOs.

Methods:
150 patients with MeVOs were identified on CTA, using CTP to help localize the lesions, from retrospective databases at the MUSC, Stanford, and Royal Melbourne. Additionally, 55 patients with LVOs on CTA were included. A neuroradiologist confirmed the occluded vessel on CTA for each patient. LVOs were defined as occlusions of the intracranial ICA or horizontal segment of the M1. MeVOs were defined at M2, M3, ACA (A2/A3), or PCA (P2/P3) occlusions. All cases were processed through Rapid LVO, the Rapid Vessel Density module (which assesses hemispheric differences in blood vessel density), and Rapid CTP (Ischemaview Inc., Menlo Park, CA), [AZ1] using automated hypoperfusion intensity ratio (HIR) on CT perfusion (CTP), which estimates collateral flow, differed in LVOs vs. MeVOs.

Results:
Rapid LVO alone identified occlusions in 41/150 (27.3%) of MeVO patients. Rapid Vessel Density maps identified an additional 38/150 (25.3%) patients with either a 20-25% vessel density reduction or 26-40% reduction. Together, these two modules identified 79/150 (52.6%) of MeVO patients. 54/55 (98.1%) of the LVOs were detected by the Rapid LVO module. The mean HIR was lower in MeVO vs. LVO patients (0.25 vs. 0.45, P-value < 0.001). Patients with M1 or ICA occlusions (LVOs) had average HIRs of 0.46 and 0.47 respectively. Patients with M2, M3, ACA, or PCA occlusions (MeVOs) had average HIRs of 0.30, 0.14, 0.22, and 0.20 respectively.

Conclusion:
MeVos detection was almost doubled with the use of the RapidAI Vessel Density in conjunction with the LVO module.
Abstract WMP73: Minimally Invasive Surgery for Intracerebral Hemorrhage: Meta-Analysis of High Quality RCTs
Authors: Alkhiri Ahmed , Alamri Aser , Almaghrabi Ahmed A , Alghamdi Basil A , Alharbi Abdullah , Alturki Fahad , Alhazzani Adel A , Al-ajlan Fahad S
Published: February 2024

Background:
Intracerebral hemorrhage (ICH) represents a devastating clinical entity with disproportionately higher rates of mortality and functional disability compared to ischemic stroke. As large trials of craniotomy in ICH failed to prove functional benefits, minimally invasive surgery (MIS) represents a potential frontier of ICH management with evidence of functional and mortality improvements. We aimed to provide level A evidence of MIS role in ICH management.

Methods:
Independent authors searched four electronic databases (Medline, Embase, Web of Science, and CENTRAL) and assessed the methodological quality of included studies using the Cochrane risk of bias tool (RoB2). Only high-quality (low risk of bias in all RoB2 domains) randomized clinical trial (RCTs) were included. We pooled odd ratios (ORs) with corresponding 95% confidence intervals (CIs) using random-effects model.

Results:
Six high-quality RCTs met our inclusion criteria. Among 1551 ICH patients, 810 were allocated to the MIS group and 741 to non-MIS. MIS was associated with significantly lower odds of mortality or disability at 90-days (OR, 0.71 [95% CI, 0.52-0.97]; p = 0.03) and lower odds of 90-days mortality (OR, 0.71 [95% CI, 0.49-1.03]; p = 0.07). Rates of functional independence and favorable functional outcomes was higher in MIS treated individuals (OR, 1.81 [95% CI, 0.78-1.79]; p = 0.43) and (OR, 1.31 [95% CI, 0.96-1.78]; p = 0.09), respectfully.

Conclusions:
This meta-analysis provides level A evidence that supports the current notion of mortality and functional improvement in ICH individuals treated with MIS. Further RCTs are warranted to validate the generalizability of these results.
Abstract WMP8: Tenecteplase vs Alteplase: is Pro-Inflammatory and Procoagulant Response Any Different in Acute Ischemic Stroke?
Authors: Hegde Sheetal , Stone Suzanne , Ray Bappaditya S
Published: February 2024

Introduction:
Thrombolysis in acute ischemic stroke (AIS) using Tenecteplase (TNK) is gaining popularity compared to Alteplase (ALT) for its practical advantages. At our center, we observed an improvement in clinical outcome in TNK treated patients compared to ALT. Hence, we aimed to study the pro-inflammatory and procoagulant responses post-thrombolysis and their contributory role in clinical outcome.

Methods:
This is a single-center retrospective study of ALT or TNK treated AIS patients admitted to a comprehensive stroke center over a 3-year period. Non-parametric tests were used to compare differences between the ALT and TNK cohorts. Peripheral blood indices, including neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR), monocyte to lymphocyte ratio (MLR), and mean platelet volume to platelet count ratio (MPV:PLT), were calculated. Their rise from pre-thrombolysis baseline during the first 48 hours was used to define a systemic inflammatory and procoagulant response. A p-value of <0.05 was considered statistically significant.

Results:
During the study period, 165 and 64 patients were treated with ALT and TNK respectively. The baseline demographics, vascular risk factors, and admission stroke severity were similar. Admission NLR, PLR, MLR, and MPV:PLT were not statistically different. Clinical outcome at 3 months assessed using median modified Rankin Scale (mRS) was better with TNK (2.0 [IQR, 1.0, 4.0] vs 3.0 [IQR, 2.0, 5.0]; p = 0.0007). Rise in NLR was significantly higher in the ALT cohort compared to TNK on day 1 (2.25 [IQR, 0.0, 5.77] vs. 0.49 [IQR, -0.48, 3.91], p = 0.01) and day 2 (1.58 [IQR, -0.09, 5.68] vs. 0.39 [IQR, -0.96, 2.91], p = 0.045). Similarly, MLR on day 2 in the ALT cohort (0.16 [IQR, 0.05, 0.49] vs. 0.12 [IQR, -0.05, 0.22], p = 0.038) and MPV:PLT on day 1 (0.61 [IQR, 0.16, 1.35] vs. 0.32 [IQR, 0.003, 0.68], p = 0.002) and day 2 (0.83 [IQR, -0.35, 1.90] vs. 0.36 [IQR, -0.12, 1.21], p = 0.004) were higher.

Conclusions:
Patients treated with TNK had better mRS scores compared to ALT in our study. This was associated with significantly less inflammatory and procoagulant response during the first 48 hours of AIS in the TNK group. The etiology for such an association is speculative and needs confirmation using more specific biomarkers.
Abstract WMP87: Characteristics and Outcome of Endovascular Treatment for Intracranial Atherosclerotic Occlusion: Comparison With Cardiogenic Cerebral Embolism in the K-NET Registry
Authors: Ueda Toshihiro , Takeuchi Masataka , MORIMOTO MASAFUMI , Yamamoto Ryoo , Tsuboi Yoshifumi , Kaku Shogo , Onodera Hidetaka , Tatsuno Kentaro , Takaishi Satoshi , Yamano Yoshihisa
Published: February 2024

Purpose:
The technique and efficacy of endovascular treatment (EVT) for intracranial atherosclerotic occlusion (ICAD) have not been established. The purpose of this study was to compare the outcomes of EVT for ICAD with those of cardiogenic cerebral embolism (CE) based on real-world data from a multicenter, prospective registry study (K-NET registry) involving 40 centers in Japan.

Methods:
The K-NET study enrolled 3187 EVTs in 2018-2021, of which 358 (11%) were ICAD and 1870 (59%) were CE. Medium vessel occlusion and tandem lesions were excluded. Indications and methods of treatment were performed at the discretion of each center. The primary endpoint was mRS: 0-2 at 90 days, and secondary endpoints included degree of recanalization, symptomatic intracranial hemorrhage.

Results:
The ICAD and CE groups showed significant differences in median age 73 and 78 years, 36% and 51% female, and baseline NIHSS 16 and 19, respectively. The occluded vessels were ICA 15% and 25%, MCA (M1/M2) 71% and 68%, and BA/VA 14% and 7%. Recanalization rates (TICI2b/3) were 75% and 91%. Time from puncture to recanalization was 68 and 42 minutes, and symptomatic intracranial hemorrhage was significantly different between 1.4% and 4.2%, while good outcome was similar between 40% and 38%. Balloon angioplasty was the treatment technique in 35% and 1.1%, and intracranial stents in 6.4% and 0.05%, respectively. Reocclusion was 3.1% and 0%, recurrent stroke 6.4% and 2.8%, and repeat endovascular treatment 5% and 0.6%, respectively. Factors significantly associated with good outcome in both groups were age, NIHSS, ASPECTS, recanalization, time from presentation to recanalization, and intracranial hemorrhage; in the ICAD group, additional significant factors were intravenous tPA and time from puncture to recanalization.

Conclusion:
EVT for ICAD was characterized by younger age, lower NIHSS, lower recanalization rate, longer puncture-recanalization time, but outcomes were similar to the CE group. The ICAD group had more additional procedures for recanalization, re-occlusion, and recurrence than the CE group.
Abstract WMP96: When to Change? Altering Strategies in Mechanical Thrombectomy May Impact Reperfusion Rates
Authors: Nascimento Martins Pedro , Tarek Mohamed , Nogueira Raul G , Dolia Jaydevsinh N , Grossberg Jonathan A , Pabaney Aqueel , Al-Bayati Alhamza , Haussen Diogo C
Published: February 2024

Introduction:
Earlier and greater reperfusion in mechanical thrombectomy (MT) leads to better clinical outcomes. The timing and potential benefit of switching thrombectomy techniques after failed device passes remains unclear.

Methods:
Retrospective analysis of a prospective comprehensive stroke center database including patients with intracranial ICA, MCA M1/M2, or Basilar occlusions undergoing MT with either Stent-Retriever (SR), Contact Aspiration (CA) or Combined technique (CT) from 2015 to 2023. Our primary endpoint was complete/near-complete reperfusion (eTICI 2c-3) at pass #2 (after pass #1 failure). Secondary endpoints included 1) eTICI2b-3 at pass#2, and 2) eTICI2c-3 with pass #3 (following failure in two consecutive passes with the same technique). We used logistic or Firth regression to compare reperfusion rates and Kaplan-Meier analysis for cumulative rates.

Results:
Among 3130 MTs in the study period, 1810 met inclusion criteria. Median age [IQR] was 65 [55 - 76] years and 51.5% were male. Following a failed first pass, switching from CA to either CT or SR was associated with higher eTICI 2c-3 (aOR [95%CI] 2.8 [1.3 - 6.5] and 7.4 [1.4-54.8], respectively). Changing from CT or SR to any other technique was not associated with higher reperfusion. Secondary endpoint analysis for eTICI2b-3 yielded comparable results. For the third pass, switching to CT after two repeated failed SR or two repeated failed CA attempts was associated with higher eTICI 2c-3 as compared to repeating the original strategy (SR aOR 5.8 [1.4 - 33.3]; AC aOR 5.6 [1.1 - 41.2]). We did not observe benefit in switching to alternative technique following one or two consecutive passes with CT. After three repeated attempts with the same technique, CT led to greater eTICI 2c-3 as compared to SR and CA (83% vs. 72% vs. 64%, p < 0.001).

Conclusions:
While limited by small subgroup sample sizes, our study strengthens the hypothesis that early changes in MT technique may have an impact on reperfusion. Our data indicates that if CA fails on first pass, transition to SR or CT should be considered. After two failed consecutive SR or CA passes, transition to CT should be contemplated.
Abstract WP1: Analyzing Door-to-Needle Time Trends: Tenecteplase vs. Alteplase in Acute Ischemic Stroke Treatment
Authors: Rodriguez Nathaniel , Prasad Sidarrth , Gealogo Brown Gretchel , Bandela Sujani , Stone Suzanne , Olson Daiwai M , Anderson Jane A , Savitz Sean I , Flores Salvador Cruz , Warach Steven J , Rhodes Charlotte , Goldberg Mark P , Birnbaum Lee
Published: February 2024

Introduction:
Tenecteplase (TNK) presents potential advantages in the treatment of acute ischemic stroke (AIS) and is hypothesized to reduce door-to-needle times (DTN).

Methods:
The Lone Star Stroke (LSS) registry incorporates data from 9 (6 CSC, 3 PSC) Texas hospitals which have and have not switched to TNK, mapping subject data to Get-With-the-Guidelines (GWTG) stroke variables and including patients who received alteplase (ALT) or TNK from October 2019 to March 2023. The dataset is stratified into ALT and TNK groups, generating a univariate table for each measured variable which is further analyzed by descriptive statistics. Polynomial regression models for both ALT and TNK are constructed to explore trends in DTN.

Results:
Of 621 patients, 459 received ALT and 162 received TNK. The groups had similar mean ages [66.8 (14.4) vs 69.2 (14.7); P=.074], and similar NIHSS scores [11.1 (8.1) vs 11.1 (7.5); P>.977]. The median DTN for ALT of 44 (32-61) mins was similar to 43 (32-61) mins for TNK (P>.05). The proportion of patients meeting DTN cut points was similar, comparing ALT to TNK for <60 minutes (73.9% vs 74.5%); for <45 minutes (50.3% vs 54.3%); and <30 minutes (20.7% vs 21.0%). As shown in Figure 1, regression models indicate no significant temporal trends for ALT (r
2
=.006; P=.08) nor for TNK (r
2
=.015; P=.12).

Conclusion:
Both TNK and ALT displayed comparable DTN times and exhibited similar temporal trends. Given the timeframe of our cohort, these decreasing trends in DTN times may be influenced by relaxed COVID restrictions and reduced workflow delays. The transition to TNK does not appear to impact workflow nor does it appear to impact stroke core measures. This is likely due to similar inclusion and exclusion criteria, as well as similar administration processes for both medications. The results are encouraging for hospitals seeking to transition to TNK in that these hospitals are unlikely to experience a change in DTN or other stroke core measures during the transition period.
Abstract WP102: Impact of National Universal Health Coverage on Access to Mechanical Thrombectomy: A Sub-Analysis of the Mechanical Thrombectomy Global Access for Stroke (MT Glass)- A Mission Thrombectomy Study
Authors: Desai Shashvat , Ortega-Gutierrez Santiago , Otite Fadar , Atchaneeyasakul Kunakorn , Limaye Kaustubh , Jadhav Ashutosh P , Herial Nabeel A , Urrutia Victor C , Szeder Viktor , Yavagal Dileep R , Asif Kaiz S
Published: February 2024

Background:
The WHO’s third Sustainable Development Goal (SDG Target 3.8) identifies Universal health coverage (UHC) as a target for countries to attain by 2030. The availability of UHC is intricately linked to access to emergency healthcare without incurring financial hardship. The MT-GLASS study demonstrated that access to mechanical thrombectomy (MT) on a global level is minuscule, with enormous disparities between countries. We aim to study the impact of national UHC on access to MT.

Methods:
The MT-GLASS survey was conducted in 75 countries through the Mission Thrombectomy 2020+ (MT2020+) global professional peer volunteer network. The primary endpoints were the current annual Mechanical Thrombectomy Access (MTA), MT operator availability, and MT center availability in the country. MTA was defined as the estimated proportion of patients with LVO receiving MT annually. The availability metrics were defined as ([current MT operatorsх50/current annual number of estimated thrombectomy-eligible LVOs]х100 = MT operator availability) and ([current MT centersх150/current annual number of estimated thrombectomy-eligible LVOs]х100= MT center availability). The metrics used an optimal MT volume per operator of 50 and an optimal MT volume per center of 150. UHC was measured using the service coverage index (SCI: ranges 1-100- per WHO).

Results:
Of the 59 countries with complete data, the median SCI was 72 (61-78) [Figure-1A- Countries in SCI groups]. Countries with SCI <72 have significantly lower MT access rates, MT center and operator availability, reimbursement facilities, and healthcare spending by GDP (Table in Figure-1B). On multivariable regression analyses, SCI is an independent predictor of MT access [OR-4.5 (1.2-8.2) p=0.02].

Conclusions:
National universal health coverage is a significant predictor of access to mechanical thrombectomy for LVO stroke patients.
Abstract WP105: Outcomes From the 1st 100 Stroke Survivors Served by a Novel Tech-Enabled Post-Acute Clinical Service
Authors: Tsai Nancey , Sheehan Lauren , Wertheheimer Jeffrey , Jovin Tudor G
Published: February 2024

Introduction:
This study evaluates the outcomes of a survivor-centric, navigator-driven, technology-enabled platform supporting survivors (SS) and care partners(CP) in post-stroke recovery. At current enrollment rates, the abstract will be updated to include 100 program participants and a propensity-matched analysis of readmission rates vs. a Medicare FFS claims set for appropriately matched subjects.

Methods:
An app-based, virtual care model was used to impact survivor quality of life and improve outcomes for stroke survivors. This mixed methods study utilizes focus group feedback, survey, app usage and patient-reported outcomes data. Participants (n=50) were facilitated by a clinical navigator (OT or LCSW). Clinicians worked through phone, messaging, and video calls with the SS/CP who had shared access within the app, with separate profiles. The average duration of participation was 12 weeks but tailored to individual needs based on post-stroke impairments, social determinants, health literacy, risk factors and lifestyle management, mental health, and other resource needs. The average participant had 10 Navigator touchpoints totaling 8 hours over the duration of the program.

Results:
Clinician-assessed mRS scores were captured at 90 days following hospital discharge for 96% of participants. Significant functional improvement was seen, with 84% achieving mRS scores of 0-2 at 90 days, compared to 60% of participants at the time of enrollment. The 30- and 90-day all-cause readmission rates for survivors were 5% and 10%, respectively, superior to recent publications reporting 30-day unplanned readmission rates after stroke ranging from 8.7%-12.5%, and 90-day readmissions ranging from 18.9% to 20.7%.

Conclusion:
These preliminary outcomes indicate that a tech-enabled healthcare services program can engage and impact the outcomes of individuals and care partners during stroke recovery.
Abstract WP107: Temporal Trends in Ischemic Stroke-Related Mortality With Concomitant Cocaine Drug Abuse in Age Group of 15-55 Years From 1999-2020 in US
Authors: Chaychi Muhammad T , Mannan Muhammad S , Sohaib Muhammad , Ahmed Muhammad K
Published: February 2024

Objectives:
The purpose of this study was to assess the trends in mortality rate after ischemic stroke and cocaine drug abuse in different demographics in the United States, compared to non-cocaine users.

Introduction:
Cocaine misuse has been linked to a higher risk of stroke. This has been observed in the US over the last decade and requires further investigation.

Methods:
Death certificates from Centers for Disease Control and Prevention Wide-Ranging On Line Data for Epidemiologic Research database were examined from 1999 to 2020 for multiple causes of death MCD-ICD 10 Codes (F14.0-14.9 and T40.5). Age-adjusted mortality rates (AAMRs) per 1000,000 persons and annual percent change (APC) were calculated and stratified by ten-year age group, sex, race/ethnicity, and urbanization.

Results:
From 1999 to 2020, adults aged 15-55 had 307,615 stroke-related deaths and cocaine-related death were 180,155 and combined stroke plus cocaine-related deaths were 6392.. The AAMR inclined from 1.7 in 1999 to 2.6 in 2007 (APC: 5.4; 95% CI: 3.6 to 8.2), after which it declined to 1.5 in 2010 (APC: -21.32; 95% CI: -25.8 to 12.6), then steadily inclined to 1.6 in 2020 (APC: 2.50, CI: 0.57 to 6.4). Men had consistently higher AAMR than women from 1999 (AAMR men: 1.9 vs women: 1.6) to 2020 (AAMR men: 2.3 vs. women: 0.9). Non-Hispanic (NH) Black or African American adults had the highest overall AAMR (7.8), followed by Hispanic or Latino (2.8), followed by NH White (1.8). AAMR also varied substantially by Urbanization.

Conclusions:
Deaths from cocaine-related stroke rose from 2007-2010, then declined until 2020. African American adults and men in large cities had high mortality rates. Preventing stroke related to drug abuse is crucial..
Abstract WP109: Framework for Evaluating Sequential Patterns in Post-Acute Transitions of Care Among Ischemic and Hemorrhagic Stroke Survivors: Analysis of Medicare Beneficiaries in the State of Texas
Authors: Pan Alan P , Wozny Joseph , Schaefer Caroline , Bako Abdulaziz , Potter Thomas B , Nicolas Charlie , Caballero Elizabeth , Nair Rejani R , Ganduglia-Cazaban Cecilia , Vahidy Farhaan
Published: February 2024

Background:
Utilizing medical claims derived information, we evaluated temporal trends in post-acute care utilization pathways among patients with acute ischemic stroke (AIS) or intracerebral hemorrhage (ICH).

Methods:
Data were retrieved from a CMS Qualified Entity housing healthcare utilization data for ≥80% of the Texas state population (100% of Medicare Fee-for-Service). Analytical sample included all Medicare enrollees with a primary discharge diagnosis (AIS or ICH) from 2016 to 2020. Episodes of care within 1 year of discharge were collated and categorized “Discharged”, “Inpatient Rehab”, “Skilled Nursing”, “Hospice”, “Readmission”, or “Death”. Sequential pattern mining was used to calculate conditional probabilities (likelihoods) of post-discharge transitions of care. Prediction rules were generated by converting care sequences into antecedent-consequent pairs. Rule based performance was evaluated by extracting 90 day sequences (antecedent) and assigning predictions of 1 year settings (consequent) based on highest likelihoods (Panel A).

Results:
A total of 82,829 AIS and 12,761 ICH hospitalizations were analyzed (described in Panel B). An example rulebook of care sequences and associated likelihoods of subsequent transitions for ICH is depicted in Panel C. Whereas ICH survivors entering inpatient rehab had respective likelihoods of 11.2% and 16.2% for subsequently being admitted to hospice care or death, those entering skilled nursing facilities had respective likelihoods of 21.9% and 30.5%. Using 90 day transition of care sequences, predictive accuracy of exact 1 year setting for AIS was 65.3% (1 attempt) and 84.0% (2 attempts); for ICH, the respective accuracy was 50.9% and 82.3% (Panel D).

Conclusion:
Post stroke transitions of care patterns may yield insights as to the long-term trajectory of outcomes. Predictive capability is expected to strengthen with planned multi-modal integration of EMR-derived clinical and imaging features.
Abstract WP118: Ischemic Core Volumes and Collateral Status Have Diurnal Fluctuations - A Retrospective Cohort Study of 18137 Patients Using Automated Perfusion Imaging
Authors: Lun Ronda , Sreekrishnan Anirudh , Albers Gregory W
Published: February 2024

Introduction:
Circadian rhythms have recently been shown to influence stroke incidence and progression of infarct. We aimed to describe the diurnal variations in the incidence and perfusion profiles of patients with ischemic stroke using a large, multi-center, automated imaging database.

Methods:
The RAPID Insights database was queried from 02/01/2016 to 01/31/2022 for patients with perfusion imaging and automated detection of an ischemic stroke due to a presumed large vessel occlusion. Exclusion criteria included: patient age ≤25, mismatch volume of <0 cc, and failure to register a positive value on either cerebral blood flow (CBF) reduction of 38% less than normal or total mismatch volume. Imaging time was subdivided into three epochs: Night: 23:00h-06:59h and Day: 07:00h-14:59h, and Evening: 15:00h-22:59h. Perfusion parameters were defined as the following: core volume was defined as CBF of <30% of normal, penumbra was defined as a Tmax delay of >6 seconds minus core volume, and collateral circulation was estimated with the Hypoperfusion Intensity Ratio (HIR = [Tmax>10s]/[Tmax>6s]), where a higher HIR suggests poorer collateral status. All perfusion parameters were analyzed on a 24-hour continuous cycle. Statistical significance was tested using a sinusoidal regression analysis.

Results:
A total of 18,137 cases were analyzed. The peak incidence of ischemic stroke occurred around noon. A sinusoidal pattern was present, with larger ischemic core volumes and higher HIR during the night compared to the day: peak ischemic core volume of 23.40 cc occurred with imaging performed at 3:56 AM (p<0.001) and peak HIR of 0.35 at 3:40 AM (p<0.001).

Conclusion:
We found that ischemic core volumes were larger and collateral status worse at nighttime compared to daytime in this large national database. These findings support the notion that poor collateral recruitment with subsequent larger ischemic stroke volumes may occur at night.

Fig 1.
Logarithmic values of ischemic core volumes and hypoperfusion intensity ratios (HIR) are plotted against a 24-hour cycle, demonstrating a sinusoidal pattern for both.
Abstract WP125: The Presence of a Ghost Infarct Core is Associated With Fast Core Growth in Acute Ischemic Stroke
Authors: Saito Mikito , Kawano Hiroyuki , Adachi Takuya , Gomyo Miho , Yokoyama Kenichi , Shiokawa Yoshiaki , Hirano Teruyuki
Published: February 2024

Introduction:
The overestimation of ischemic core volume by computed tomography perfusion (CTP) is a critical concern in the selection of candidates for reperfusion therapy. This phenomenon is termed a ghost infarct core (GIC). Core growth rate has emerged as an indicator of ischemic severity. The aim of the present study was to elucidate the association between the presence of a GIC and the core growth rate.

Methods:
Consecutive patients with acute ischemic stroke due to large vessel occlusion who underwent mechanical thrombectomy in our institute from March 2017 to July 2022 were enrolled. The initial ischemic core was measured by pretreatment CTP, and the final infarct volume (FIV) was measured by diffusion-weighted imaging. A GIC was defined by initial ischemic core volume minus FIV >10 mL. The core growth rate was calculated by dividing the initial ischemic core volume by time from stroke onset to CTP acquisition. Univariable analysis and a multivariable logistic regression model were used to evaluate the association between GIC-positive and the core growth rate; complete recanalization, onset to imaging time, and imaging to recanalization time were included as covariates.

Results:
Ninety-one patients were included in the study. Of these, 21 patients (23.1%) were GIC-positive. The GIC-positive group had higher core growth rate (14.2 [2.6-46.7] vs 4.8 [1.6-17.1] mL/h, p=0.021) and complete recanalization (n=15 (71.4%) vs 29 (41.4%), p=0.016) compared to the GIC-negative group. On receiver operating characteristic curve analysis, the optimal cutoff point of the core growth rate to predict GIC-positive was 22 mL/h (sensitivity, 0.48; specificity, 0.85; area under the curve, 0.67). Multivariable logistic regression analysis showed that core growth rate ≥22 mL/h (OR 6.44, 95% CI [1.59-26.10], p=0.006) and complete recanalization (OR 3.72, 95% CI [1.14-12.08], p=0.022) were independent predictors of GIC-positive.

Conclusions:
A GIC was associated with fast core growth in acute ischemic stroke. Overestimation of the initial ischemic core may be determined by core growth speed, not a clock time.
Abstract WP142: Investigating the Association of Intracranial Stenosis With Low Wall Shear Stress
Authors: Tariq Muhammad Bilal , Li Chuanlong , Apfel Ryan , Beaman Charles , Prochilo Grace , Scalzo Fabien , Kaneko Naoki , Hinman Jason D , Liebeskind David S
Published: February 2024

Background:
Intracranial atherosclerotic disease (ICAD) is associated with high recurrence rates of stroke despite aggressive medical management. Low wall shear stress (WSS) alters endothelial function and changes in WSS within the post-stenotic region of ICAD lesions is a potential driver of stroke recurrence.

Methods:
Using the SAMMPRIS imaging dataset, we identified medically managed patients with symptomatic middle cerebral artery (MCA) stenosis measured by CTA. WSS was calculated by creating a 3D volumetric mesh from CTA source imaging. Pulsatile flow profile reference standard boundary conditions were applied at pressure outlets to simulate normal hemodynamics. Arterial segments extending from the stenosis to the MCA bifurcation were captured and quantified. Contralateral arterial segments were matched by length and area. The ratio of area with low WSS (<4 dyne/cm
2
) on both sides was then calculated. Differences in the mean arterial area with low WSS and ratio of area with low WSS were compared using paired Student’s t-test with data presented as mean ± SD.

Results:
Of 451 cases in SAMMPRIS, the medical management arm had 105 MCA cases of which 47 cases had CTA available and 33 cases were able to be analyzed by computational flow dynamics. Symptomatic ICAD lesions demonstrated significant differences in post stenosis area with low WSS (24.7±43.4 mm
2
vs 2.8±3.4 mm
2
p=0.003) and differences in the low WSS ratio (0.25±0.26 vs0.04±0.05 p<0.001). There was no statistically significant difference in the length and area of the arterial segment post stenosis to the bifurcation and the control length on the contralateral side (11.6±7.4 mm vs 10.6±6.1 mm p=0.566; 80.7±55.0 mm
2
vs 95.4±58.3 mm
2
p=0.298).

Conclusion:
Area with low WSS after ICAD stenoses is increased in the SAMMPRIS imaging dataset and may be a marker of symptomatic ICAD. Further studies are needed to evaluate the association of post stenotic WSS with symptomatic recurrent stroke.
Abstract WP154: Factors Associated With Prolonged Length of Intensive Unit Stay Following Mechanical Thrombectomy for Acute Ischemic Stroke
Authors: Khan Hamza , Chaudhry Saqib A , Laleka Maham , Chaudhry Mohammad Rauf A , Khan Muhammad Taimoor , Baig Mohammad W , Qureshi Adnan , Shuaib Ashfaq
Published: February 2024

Objective and Background:
The objective of the study was to investigate factors affecting the length of stay (LOS) in the intensive care unit (ICU) following mechanical thrombectomy (MT) for acute ischemic stroke.

Methods:
We identified patients undergoing MT from a prospective registry at a comprehensive stroke center between January 2021 and June 2023. ICU stay for more than 48 hours was defined as prolonged ICU stay.

Results:
Out of 363 patients, 41.6% (n=151) required a prolonged ICU stay. Prolonged ICU stay were more likely to have higher baseline median NIHSS score (19 vs. 14%, p < 0.0001), posterior circulation stroke (12.6% vs. 5.7%, p = 0.0200), intubation for the procedure (86.7% vs. 69.3%, p = 0.0001), complications including pneumonia (18.5% vs. 6.1%, p = 0.0002), deep vein thrombosis (7.3 vs. 2.3, p = 0.0242), urinary tract infection (12.6% vs. 6.1%, p = 0.0326), and symptomatic intracerebral hemorrhage (7.3% vs. 1.9%, p = 0.0109). Patients receiving thrombolysis prior to thrombectomy were less likely to have a prolonged LOS (27.8% vs. 41.7%, p = 0.0086). Independent predictors for prolonged ICU LOC included higher NIHSS (odds ratio [OR] 2.7, p = 0.0002), intubation prior to the procedure (OR 2.7, p = 0.0002), not receiving IV thrombolysis (OR 2.3, p = 0.0069), thrombolysis in cerebral infarction (TICI) score ≥ 2B (OR 0.458, p = 0.0754), composite ICU complications (OR 2.4, p = 0.0027), and symptomatic intracranial hemorrhage (OR 5.2, p = 0.0157).

Conclusions:
Almost one-third of the acute ischemic stroke patients required a prolonged ICU stay following MT. A better understanding of the factors associated with prolonged ICU stay may assist in appropriate allocation of resources.
Abstract WP155: Epidemiology of Posterior Reversible Encephalopathy Syndrome (PRES) in the United States: A National Inpatient Sample Study
Authors: Seitz Alison , Zhang Cenai , Qadourah Haneen , Parauda Sarah , Kaiser Jed , Liao Vanessa , Navi Babak B , Kamel Hooman , Liberman Ava L
Published: February 2024

Introduction:
Posterior reversible encephalopathy syndrome (PRES) is an increasingly recognized and potentially devastating cerebral dysregulation syndrome. The epidemiology of PRES and its associated manifestations have been underreported. We therefore sought to determine the prevalence and clinical severity of PRES among hospitalized patients in the United States (US).

Methods:
We conducted a retrospective cohort study using US data from the National Inpatient Sample (NIS) for the years 2016 to 2019. To identify patients with PRES, we used the ICD-10-CM diagnostic code I67.83, which was previously found to have a sensitivity of 100% (95% CI, 87%-100%) and a specificity of 88% (95% CI, 73%-97%) as compared to chart review. To characterize disease severity, we report the coincidence of any stroke (ischemic stroke, intracerebral hemorrhage [ICH], subarachnoid hemorrhage [SAH]) using previously validated ICD-10-CM codes, length of stay, need for mechanical ventilation, and discharge destination. Standard descriptive statistics with 95% CI are used to detail our findings.

Results:
We identified 39,460 hospitalizations for PRES among adults, which accounts for 0.03% of hospitalizations during the study period. The median age of PRES patients was 57 years (IQR, 41-67), 27,583 (69.9%) were female, and 26,399 (66.9%) were of White race. A total of 33,107 patients (83.9%) had a history of hypertension. Among patients with PRES, 3,950 (10.0%; 95% CI, 9.4-10.7%) had an ischemic stroke, 1,685 (4.3%; 95% CI, 3.8-4.7%) had ICH, and 995 (2.5%; 95% CI, 2.2-2.9%) had SAH during their index hospitalization. The median length of stay was 6 days (IQR 4-12), one quarter required mechanical ventilation, and half were discharged to home.

Conclusion:
In a representative US sample, we found that PRES is a rare disorder with relatively low rates of coincident ischemic and hemorrhagic stroke reported at index hospitalization.
Abstract WP158: Cortical Superficial Siderosis is Associated With Ischemia After Intracerebral Hemorrhage
Authors: Ridha Mohamed , Simonetto Marialaura , Carvalho Poyraz Fernanda , Hess Evan , Kumar Aditya , Agarwal Sachin , Ghoshal Shivani , Claassen Jan , Connolly Edward , Park Soojin , Roh David
Published: February 2024

Background:
Ischemia on diffusion weighted imaging (DWI) after intracerebral hemorrhage (ICH) increases the risk of future ischemic stroke. Radiographic markers of small vessel disease, including cerebral microbleeds (CMB), are associated with DWI lesions. Though cortical superficial siderosis (cSS) is also a hemorrhagic small vessel disease subtype, it is unclear if cSS similarly relates to DWI lesions. We hypothesized that cSS would represent a more severe phenotype of small vessel disease and would associate with DWI lesions after ICH independent to other small vessel disease markers.

Methods:
Using the Intracerebral Hemorrhage Outcomes Project (ICHOP), we included all cases of spontaneous ICH who underwent DWI and susceptibility imaging/gradient echo. DWI hyperintensities were identified if >10mm from the hematoma with decreased ADC signal. cSS were identified as subarachnoid hemosiderin deposition without acute subarachnoid hemorrhage. The relationship of cSS with DWI lesion presence as the outcome was assessed with logistic regression adjusted for ICH score, blood pressure change within 24 hours, and small vessel disease markers (CMB and white matter hyperintensity). Sensitivity analyses were performed to adjust for demographics and ICH location. A secondary analysis using linear regression assessed the association with the number of DWI lesions adjusted for similar covariates.

Results:
Of 198 patients analyzed, DWI lesions were observed in 31.3% and cSS in 10.6%. The presence of cSS was associated with DWI lesions (adjusted OR 3.72, CI: 1.29-10.72), independent of other small vessel disease markers. Separate sensitivity analyses adjusting for sex, race, and ICH location did not change the association of cSS with DWI lesions. In secondary analyses, cSS was not associated with greater number of DWI lesions counts (b 0.213, CI -0.53-0.63).

Discussion:
cSS is associated with the presence of DWI lesions, independent to other small vessel disease markers. cSS may represent a severe phenotype of small vessel disease with a risk of ICH recurrence and ischemia. Further work is required to investigate underlying mechanisms and optimal strategies to mitigate competing risks of future hemorrhage and ischemic events in these patients.
Abstract WP162: Myelin Suppresses Macrophage Responses to Diverse Stimuli
Authors: Delong Jonathan , Sun Leonardo , Velazquez Sofia , Landreneau Margaret , Sansing Lauren H
Published: February 2024

Introduction:
In intracerebral hemorrhage (ICH), blood-derived macrophages initially contribute to a neurotoxic inflammatory response. Understanding the endogenous signals that control this response could help limit these effects. Uptake of myelin debris limits macrophage inflammatory cytokine production in response to LPS, possibly due to the cholesterol present in myelin. However, the pathways by which myelin suppresses macrophage responses and the broader impacts of myelin on macrophage phenotype are poorly understood.

Methods and Results:
RNA sequencing was used to examine impacts of myelin in diverse conditions. BMDMs were pretreated with myelin, cholesterol or T0901317, an agonist of the cholesterol-response transcription factor LXR. The cells were stimulated with Type I cytokines, Type II cytokines, and different TLR agonists to mimic the diverse stimuli encountered in the inflamed brain (Fig 1A). Myelin suppressed responses to all stimulations, as did T0901317. Cholesterol suppressed the response to LPS and had little effect on other stimulations, including the ICH-relevant alarmin S100A9 (Fig 2). Gene Ontology Enrichment showed that many of the inflammatory gene pathways suppressed by myelin were unique for each stimulation although lipid metabolism pathways were shared across stimulations.

Conclusions:
Myelin broadly limits macrophage responses to diverse stimulations, partially though not completely through cholesterol and activation of LXR. Cholesterol does not suppress the response to S100A9, suggesting that other components of myelin or activation of phagocytic receptors contribute to suppression of the macrophage response during ICH.
Abstract WP172: A Novel Score to Predict Early Time From Symptom Onset to Hospital Arrival in Patients With Intracerebral Hemorrhage
Authors: Balali Pargol , Morotti Andrea , Joundi Raed A , Katsanos Aristeidis , Catanese Luciana , Lioutas Vasileios , Carvalho Filipa , Heistand Elizabeth , Sharma Mukul A , Selim Magdy H , Shoamanesh Ashkan
Published: February 2024

Introduction:
Up to 40% of ICH patients have unknown onset time, leading to uncertainty regarding the use of hyperacute ICH treatments and their exclusion from acute ICH treatment trials. We aimed to develop a prediction score that can reliably identify ICH patients presenting within 3 hours of symptom onset.

Methods:
Spontaneous ICH patients participating in the iDEF trial with available prerequisite data were analyzed. A stepwise multivariable logistic regression model was used to determine predictors of early presentation (symptom onset-to-baseline CT scan time ≤3 hours) with a p-value < 0.15. To develop the prediction score, we allocated scores proportional to the standardized odds ratio (OR) of each binary variable. Continuous variables were dichotomized using the lowest threshold above which there was no additional gain in the positive predictive value (PPV) for early presentation.

Results:
Of 291 iDEF participants, 132 (45%) presented early. Baseline NIHSS (OR 1.05 per 1-score increase; 95% CI, 0.99-1.11), Glasgow Coma Scale (1.18 per 1-score increase; 1.01-1.39), ICH volume (1.17 per 10-ml increase; 0.98-1.39), absolute perihematomal edema volume (0.81 per 10-ml increase; 0.66-1.00), irregular hematoma shape (2.24; 1.12-4.48), blend sign (0.45; 0.21-0.97), white blood cell count (0.89 per 10
3
cell/ml increase; 0.82-0.96), and blood glucose levels (0.91 per mmol/l increase; 0.82-0.99) were associated with early presentation (c-statistic=0.71). The PPV for an early ICH presentation score (Figure) of >7 was 69%.

Conclusion:
This novel early ICH presentation score using readily available clinical, neuroimaging, and laboratory data has good performance for identification of ICH patients presenting within 3 hours of symptom onset. If validated in external datasets, the early ICH presentation score can be used to improve recruitment feasibility in acute ICH trials and support clinical decision-making in ICH patients with an unknown symptom onset time.
Abstract WP173: Major ABO Incompatible Platelet Transfusion is Associated With Ischemic Lesions on Brain MRI of Patients With Intracerebral Hemorrhage
Authors: Carvalho Poyraz Fernanda , Ridha Mohamed , Simonetto Marialaura , Kumar Aditya , Hess Evan , Magid-Bernstein Jessica , Connolly Sander , Ghoshal Shivani , Agarwal Sachin , Park Soojin , Claassen Jan , Hod Eldad , Roh David
Published: February 2024

Background:
We identified that major ABO incompatible platelet transfusions are associated with poor intracerebral hemorrhage (ICH) outcomes, yet the driver for this relationship is unknown and does not appear to be related to impaired hemostasis. Conversely, acute ICH patients are known to develop remote ischemic lesions on brain MRI. These ischemic lesions are associated with poor ICH outcomes, but risk factors for their formation are unknown. We explored whether major ABO incompatible platelet transfusions are associated with these ischemic lesions.

Methods:
Consecutive spontaneous ICH patients enrolled into a single-center, prospective cohort study between 2009 and 2016 were assessed. Patients receiving an acute, single platelet transfusion within 24 h of admission and a brain MRI during their ICH admission were included. Major ABO incompatible platelet transfusion was the exposure. The presence of ischemic lesions on brain MRI, defined as diffusion restriction >10 mm away from the hematoma was the outcome. Regression models assessed relationships between major ABO-incompatible platelets and ischemic lesions, adjusting for ICH severity and time to MRI.

Results:
Of 40 ICH patients with an acute platelet transfusion and MRI, the mean age was 67.1 (SD 14.1), 37.5% were female, and 20% received a major ABO incompatible platelet unit. Patients receiving a major incompatible platelet unit were more likely to have ischemic lesions (62.5% vs 21.9%), and there continued to be an association of major ABO-incompatible platelets units with these lesions after adjusting for time to MRI (OR 5.45, 95%CI 1.01-29.30, p=0.04) and ICH score (OR 9.15, 95%CI 1.37-62.67, p=0.02). Sensitivity analyses adjusting for patient blood type did not alter this relationship (OR 17.08, 95%CI 1.34-217.94, p = 0.03).

Conclusions:
Major ABO incompatible platelet units were associated with remote ischemic DWI lesions. Further work is needed to address the generalizability of our data and to clarify relationships of platelet unit characteristics, cerebral ischemia, and clinical outcomes after ICH.