14th International Symposium on Thrombolysis, Thrombectomy and Acute Stroke Therapy: Proceedings and summary of discussions

The 14th International Symposium on Thrombolysis, Thrombectomy and Acute Stroke Therapy (TTST) took place in Houston, Texas on 21-22 October 2018. Attended by 150+ invited global experts, the objectives of TTST 2018 were to explore the changing landscape of acute ischemic stroke therapy and to address current controversies in thrombolysis and thrombectomy, including expanding access and systems of care with global relevance. This article summarizes the proceedings of TTST 2018. The key points of each session are listed below, the full text of presentations and discussion are available in the online supplement, and the full list of contributing authors appear in the Appendix at the end of this article.

Real-World Treatment Trends in Endovascular Stroke Therapy

Background and Purpose- Recent landmark trials provided overwhelming evidence for effectiveness of endovascular stroke therapy (EST). Yet, the impact of these trials on clinical practice and effectiveness of EST among lower volume centers remains poorly characterized. Here, we determine population-level patterns in EST performance in US hospitals and compare EST outcomes from higher versus lower volume centers. Methods- Using validated diagnosis codes from data on all discharges from hospitals and Emergency Rooms in Florida (2006-2016) and the National Inpatient Sample (2012-2016) we identified patients with acute ischemic stroke treated with EST. The primary end point was good discharge outcome defined as discharge to home or acute rehabilitation facility. Multivariate regressions adjusted for medical comorbidities, intravenous tPA (tissue-type plasminogen activator) usage and annual hospital stroke volume were used to evaluate the likelihood of good outcome over time and by annual hospital EST volume. Results- A total of 3890 patients (median age, 73 [61-82] years, 51% female) with EST were identified in the Florida cohort and 42 505 (median age, 69 [58-79], 50% female) in the National Inpatient Sample. In both Florida and the National Inpatient Sample, the number of hospitals performing EST increased continuously. Increasing numbers of EST procedures were performed at lower annual EST volume hospitals over the studied time period. In adjusted multivariate regression, there was a continuous increase in the likelihood of good outcomes among patients treated in hospitals with increasing annual EST procedures per year (odds ratio, 1.1; 95% CI, 1.1-1.2 in Florida and odds ratio, 1.3; 95% CI, 1.2-1.4 in National Inpatient Sample). Conclusions- Analysis of population-level datasets of patients treated with EST from 2006 to 2016 demonstrated an increase in the number of centers performing EST, resulting in a greater number of procedures performed at lower volume centers. There was a positive association between EST volume and favorable discharge outcomes in EST-performing hospitals.

Serial Cerebral Metabolic Changes in Patients With Ischemic Stroke Treated With Autologous Bone Marrow Derived Mononuclear Cells

Purpose: Cell-based therapy offers new opportunities for the development of novel treatments to promote tissue repair, functional restoration, and cerebral metabolic balance. N-acetylasperate (NAA), Choline (Cho), and Creatine (Cr) are three major metabolites seen on proton magnetic resonance spectroscopy (MRS) that play a vital role in balancing the biochemical processes and are suggested as markers of recovery. In this preliminary study, we serially monitored changes in these metabolites in ischemic stroke patients who were treated with autologous bone marrow-derived mononuclear cells (MNCs) using non-invasive MRS.

Materials and Methods: A sub-group of nine patients (3 male, 6 female) participated in a serial MRS study, as part of a clinical trial on autologous bone marrow cell therapy in acute ischemic stroke. Seven to ten million mononuclear cells were isolated from the patient's bone marrow and administered intravenously within 72 h of onset of injury. MRS data were obtained at 1, 3, and 6 months using a whole-body 3.0T MRI. Single voxel point-resolved spectroscopy (PRESS) was obtained within the lesion and contralesional gray matter. Spectral analysis was done using TARQUIN software and absolute concentration of NAA, Cho, and Cr was determined. National Institute of Health Stroke Scale (NIHSS) was serially recoreded. Two-way analysis of variance was performed and p < 0.05 considered statistically significant.

Results: All metabolites showed statistically significant or clear trends toward lower ipsilesional concentrations compared to the contralesional side at all time points. Statistically significant reductions were found in ipsilesional NAA at 1M and 3M, Cho at 6M, and Cr at 1M and 6M (p < 0.03), compared to the contralesional side. Temporally, ipsilesional NAA increased between 3M and 6M (p < 0.01). On the other hand, ipsilesional Cho showed continued decline till 6M (p < 0.01). Ipsilesional Cr was stable over time. Contralesional metabolites were relatively stable over time, with only Cr showing a reduction 3M (p < 0.02). There was a significant (p < 0.03) correlation between ipsilesional NAA and NIHSS at 3M follow-up.

Conclusion: Serial changes in metabolites suggest that MRS can be applied to monitor therapeutic changes. Post-treatment increasing trends of NAA concentration and significant correlation with NIHSS support a potential therapeutic effect.

Does care in a specialised stroke prevention clinic improve poststroke blood pressure control: a protocol for a randomised comparative effectiveness study

INTRODUCTION

Hypertension is a major risk factor for recurrent stroke, and blood pressure (BP) reduction is associated with decreased risk of stroke recurrence. However, many stroke survivors have poorly controlled BP after their initial stroke. The Stroke Transitions Education and Prevention (STEP) Clinic was established to provide a comprehensive approach to stroke risk factor reduction.

METHODS AND ANALYSIS

This randomised comparative effectiveness study was designed to assess the impact of care in the STEP clinic versus usual care on poststroke BP reduction. Eligible hospitalised patients with ischaemic stroke, haemorrhagic stroke or transient ischaemic attack are scheduled for a clinic screening visit within 4 weeks of discharge if they meet baseline inclusion criteria. At the clinic visit, patients who have uncontrolled BP, defined as automated office BP ≥135/85 mm Hg are randomised (1:1) to either the STEP clinic or usual care for management. STEP clinic patients receive instructions to self-monitor, a BP monitor, sleep apnoea screening, dietary counselling, review of BP monitoring records and adjustment of medications. Patients are followed by a neurologist and a stroke-trained nurse practitioner. Usual care participants are seen by a neurologist and recommendations for secondary prevention are sent to primary care providers. The primary outcome is the difference in mean daytime ambulatory systolic BP at 6 months, assessed using linear regression analysis. Secondary outcomes include 24 hours ambulatory BP, medication adherence and medication self-efficacy, and composite cardiovascular events.

ETHICS AND DISSEMINATION

This study was approved by the Institutional Review Boards at the McGovern Medical School at the University of Texas Health Sciences Center and the Georgetown University School of Medicine. Uninsured and Spanish-speaking patients are included in the study.

TRIAL REGISTRATION NUMBER

NCT02591394; Pre-results.

Abstract TP402: Inpatient versus Emergency Department Code Stroke via Telemedicine

Introduction: Inpatient (IP) code strokes have been noted to have worse time metrics than code strokes in the Emergency Department (ED). Telemedicine (TM) has alleviated some disparities in management of acute ischemic stroke (AIS). We compared tPA time metrics between inpatient and ED code strokes via TM.

Methods: We identified 681 AIS patients who received tPA in our Lone Star Stroke Consortium Telestroke Registry (LeSTER) from 1/2016-12/2017. There were 52 IP and 629 ED patients who underwent code strokes. We compared demographics and time metrics including TM page time to tPA (TPT) and CT scan time to tPA treatment (CTT), camera to tPA time (CAT), as well as post-tPA outcomes among the two groups using Wilcoxon rank sum test, Chi-square test, Fisher’s exact test, or logistic regression.

Results: Inpatient strokes had delayed TPT compared to ED code strokes (44.5 vs. 38 minutes; p=0.007), longer CTT (56 vs. 46 minutes; p=0.003), longer CAT (34 vs. 29 minutes; p=0.010), but has a shorter time from last known well (LKW) to TPT (47 vs. 95.5 minutes; p<0.0001). Inpatient strokes were more severe (NIHSS 10 vs. 7; p=0.011). Pre-hospitalized patients were older (72 vs. 62; p<0.001). More inpatient stroke patients were sent to hospice or expired by discharge (17.3% vs. 7.3%; p=0.011) and less likely to be sent home (46% vs. 60.5%; p=0.044). Furthermore, inpatient strokes presented a higher mortality rate (28.2% vs. 12.7%; p=0.009) in the 90 day follow up. After adjusted for age and initial NIHSS, all the differences in the disposition and mortality rate are no longer significant.

Conclusions: We found a significant delay in tPA metrics for inpatient code strokes as well as poorer clinical outcomes compared to patients who presented directly to the ED. Further investigation is needed to address gaps in the delivery of care to inpatients with suspected AIS via TM.

Abstract 100: In-Hospital Delirium and Long-Term Cognitive Outcomes Among Patients With Ischemic Stroke: A Population-Based Cohort Analysis

Introduction: Evidence of association between delirium during initial hospitalization of ischemic stroke (IS) patients, and development of long-term mild cognitive impairment or dementia (MCID) is lacking. We examined the prospective incident risk of MCID among IS patients who experienced in-hospital delirium in a large multi-state population-based cohort.

Methods: We utilized NY, CA, and FL (2005 - 2014) State Inpatient and Emergency Department Databases, and established a cohort by selecting MCID free patients with a primary diagnosis of IS (ICD-9: 433.x1, 434.x1, 436) during a 2yr period. Delirium during the initial IS event was tagged using a validated algorithm with high specificity for the confusion assessment method. The cohort was followed for MCID diagnoses. Patients that died within 90 days of initial IS event were excluded. We conducted time-to-event analyses and report cumulative incidence, 95% Confidence Interval (CI) and hazard ratios (HR) for risk of MCID among IS patients with and without delirium.

Results: A total of 133,815 IS patients (age: 70.5, female: 51.7%, white: 65.5%) were followed for up to 8yrs, resulting in 357,500 person-years. Patients who experienced delirium were significantly older and had a higher comorbidity burden. A significantly smaller proportion of delirium patients underwent IV or IA thrombolysis. Cumulative incidence (95% CI) for development of MCID was significantly higher among delirium patients (9.01, 8.32 - 9.74) as compared to non-delirium patients (3.99, 3.93 - 4.06). Likewise, the HR for MCID among delirium patients was statistically significant (1.86, 1.71 - 2.02) in the fully adjusted Cox proportional model (Figure).

Conclusion: In-hospital delirium was independently associated with a higher risk of developing MCID in this large population-based cohort. Further investigation is warranted to elucidate the mechanistic basis for the role of delirium in long-term cognitive decline among IS patients.

Abstract 45: Treatment Trends and Clinical Outcomes for Unruptured Cerebral Aneurysms in High vs Low Volume Centers

Background: Prior studies have suggested that unruptured cerebral aneurysm (CA) treatments have spread from high-volume centers into lower-volume centers in the past decade, coinciding with the increase of endovascular coiling (EC) relative to surgical clipping (SC). Our understanding of outcomes from CA treatments by hospital treatment volumes is lacking.

Methods: Using administrative data on all discharges from hospitals in New York (2005-2014) and Florida (2005-2015), we identified patients with treatments for unruptured CAs. Good outcome was defined as discharge home without intracerebral hemorrhage (ICH) and poor outcome as discharge to SNF or death. A composite weighted index of risk factors was calculated using the Charlson Comorbidity Index (CCI). Logistic regression adjusted for age, sex, smoking, diabetes and CCI were performed. Results are provided as median [IQR] or OR [95% CI].

Results: Among 14,064 patients with treated unruptured CAs, median age was 58 [49 - 66] and 75% were female. EC was performed in 9,417 (67%), and increased over time (56% vs. 74%, 2006 vs. 2014). Annual treatments increased over the study period, with 1125 CAs treated in 2006 versus 1517 in 2014, whereas the number of treating hospitals did not (66 vs. 64, 2006 vs. 2014). In adjusted logistic regression, there was no difference in likelihood of a good outcome over time (OR 0.94 [0.86 - 1.03], 2012-2015 vs. 2005 - 2008). The likelihood of good outcome increased with annual hospital treatment volume ( Figure 1a ). This relationship was maintained for patients treated with SC and EC (ORs 1.7 [1.33 - 2.2] and 3.2 [2.5 -4.1]). The likelihood of poor outcome conversely decreased consistently with increasing annual treatment volume ( Figure 1b ).

Conclusion: In this large cohort study, we did not observe an increase in the number of hospitals performing CA treatments. However, for patients treated with both SC and EC, treatment at higher-volume centers was associated with improved outcomes.

Abstract WP180: Association Between Medicare Reform and Access to Rehabilitation in Ischemic Stroke Patients

Introduction: In 2010, the Centers for Medicare and Medicaid Services (CMS) implemented the Inpatient Rehabilitation Facility Prospective Payment System (IRF PPS) Rule, requiring IRF patients to tolerate 3 hours of daily therapy (PT &OT/SLP). If unable, rehab at a skilled nursing facility (SNF) is recommended, contrasting the 2016 AHA Stroke Rehabilitation Guidelines for optimal recovery.

Hypothesis: Stroke patients are more likely to receive rehab at a SNF compared to an IRF after implementation of the CMS 2010 IRF PPS Rule.

Methods: We calculated the proportion of stroke patients discharged to IRF vs home and SNF vs home using prospectively collected registry data from Get with the Guidelines - Stroke, for a cohort of ischemic (85.7%) and hemorrhagic (14.3%) stroke patients between 2008 and 2015 (n=1,962,933). Univariate analyses compared stroke severity by NIHSS, sociodemographic/clinical characteristics and in hospital rehabilitation assessments. Multivariable regression modeling assessed the association between CMS 2010 IRF PPS Rule and age, teaching versus non-teaching hospital and US geographic region.

Results: Post CMS 2010 IRF PPS Rule, 1 out of 15 ischemic stroke patients had lower IRF rehab odds (OR 0.94; 95%CI 0.92-0.95; P<0.0001); 1 out of 9 ischemic stroke patients had higher SNF rehab odds (OR 1.12, 95% CI 1.10-1.14; P<0.0001). Multivariable regression - ischemic stroke: Across all ages, in the South, Northeast and at teaching hospitals, the odds of IRF rehab decreased and the odds of SNF rehab increased after implementation of CMS 2010 IRF PPS Rule (Fig 1 & 2).

Conclusions: Ischemic stroke patients, with similar clinical histories & stroke severity, had decreased odds of inpatient rehabilitation facility rehab and increased odds of skilled nursing facility rehab after implementation of the CMS 2010 IRF PPS Rule. Additional studies analyzing the effects of low intensity SNF rehab versus IRF rehab on return home and long-term disability are needed.

Abstract TP303: The Effect of Telemedicine in IV-tPA Time Metrics of Acute Ischemic Stroke on and After-hours at Medically Underserved versus Non-medically Underserved Areas

Introduction: Telemedicine (TM) may alleviate disparities in patients with acute ischemic stroke (AIS) in rural or medically underserved areas (MUAs) by increasing access to specialists. AIS metrics may also differ between patients who present to emergency rooms during nonworking hours. We compared time metrics and outcomes of AIS patients who received intravenous tissue plasminogen activator (IV-tPA) via TM during on-hours and after-hours at hospitals in MUAs with those during on-hours and after-hours at hospitals in non-MUAs.

Methods: We identified suspected AIS patients who received IV-tPA via TM from 9/2016 - 12/2017. We compared baseline characteristics, time metrics, and outcomes between the after-hours (5pm-7:59am) and on-hours (8am-4:59pm) patients in MUAs and non-MUAs. Wilcoxon rank-sum test, Chi-square test, or Fisher’s exact test were used for two-group comparisons.

Results: Of 662 patients evaluated via TM, 297 were seen during on-hours, and 365 after-hours; with 462 patients seen at non-MUA sites and 200 at MUA sites. There were no significant differences in baseline characteristics aside from racial demographics (Table 1). There was no difference in door-to-needle-time between all groups, in spite of small differences of door to CT (non-MUA sites were 5 minutes longer after hours than MUA sites, p=0.002) and onset to door time (MUA being 10 minutes longer on hours than non-MUA, p=0.027). Outcomes were slightly poorer for MUA compared to non-MUA, including discharge disposition (home: 53.9% vs 63.7%, p=0.004) and modified Rankin Scale (mRS≥4: 43% vs 27%, p=0.001).

Conclusions: TM can provide AIS patients at spoke hospitals with 24/7 access to stroke specialists and standard of care evaluation and treatment. Lack of resources in MUA could be the reason for poorer outcomes however further research is needed.

Abstract TP347: The Stroke Transitions Education and Prevention (STEP) Clinic: A Learning Healthcare Model for Post-Stroke Care

Background and Purpose: The STEP clinic was established to provide post-acute care for stroke patients. In this learning healthcare model, optimization of processes is enriched by evaluation of patient outcomes and patient and provider feedback. Trainee education and clinical trial recruitment are key. We describe the approach, patient population, and outcomes.

Methods: STEP patients are assessed by a multidisciplinary care team within 6 weeks post-hospitalization. Patients complete depression, fatigue, and sleep apnea questionnaires. The team develops a personalized treatment and follow-up plan and provides risk factor counseling and education. We obtained data from the STEP clinical registry for patients enrolled from 10/2014 to 05/2017.

Results: Among 605 enrolled patients following up at median of 47 days, 55% were male, mean age was 62.2 (SD 14.3), and stroke types included 76% ischemic/transient ischemic attack and 20% intracerebral hemorrhage. By race, 45% were non-Hispanic white, 27% non-Hispanic black, 19% Hispanic, and 3% Asian. Initial blood pressure (BP) was controlled for 66% (<140/90 mmHg) with medications adjusted for 9%. BP control was maintained at 67% among assessed patients. Of 91% completing a depression screen, 24% had at least moderate depression, and 22% were maintained or initiated on an antidepressant. Of 92% patients completing an epworth sleepiness scale, 36% scored >9 (abnormal), and 27% were sent for a sleep study. A total of 38 trainees rotated through the clinic and 91 patients were enrolled in studies. Four novel trials, 3 randomized clinical trials and 1 observational study, were derived from the clinic.

Conclusions: The STEP clinic represents a learning healthcare model for post-stroke care. Learning healthcare models for post-stroke care are feasible and may be an effective approach to secondary and tertiary prevention.

Abstract TP437: Machine Learning Based Approach for Predicting High In-Hospital Systolic Blood Pressure Variability Among Intracerebral Hemorrhage Patients During Early Hospitalization

Introduction: Recent data suggest that early high systolic blood pressure variability (HSPBV) is associated with poor long term outcomes in intracerebral hemorrhage (ICH) patients. We employed a Machine Learning (ML) based approach to predict HSBPV during hospitalization.

Methods: Adult radiologically confirmed ICH patients were enrolled in a multisite cohort. A semi-automated algorithm extracted systolic blood pressure (SBP) data from electronic medical records (EMR) and linkage to database with demographic, clinical, and outcomes information was created. Pre-hospital and early admission variables were used to develop predictive algorithms. Patients who expired during hospitalization were excluded. Generalized estimating equations quantified inter and intra-patient SBPV. An 80/20 data split was used to train and test predictive models for HSBPV. Two supervised ML models were trained using a repeated cross-validation bagged classification and regression tree, the first with a complete set of records and the second utilizing imputation (Figure).

Results: A total of 455 patients were included with mean(SD) age 63.6 (14.98), females 36.7%, African American 34.5%, and median ICH score 2.0. The average per-patient observation time was 9.7 days resulting in 152,691 SBP readings. A 25 variable imputed model was parameterized (accuracy: 72.2%, sensitivity: 76.5%, specificity: 66.7%, and kappa: 0.43) (Figure). The top influential variables were age, hemorrhage volume, glucose, LDL, and platelets. Methodological and output contrasts with traditional likelihood-based modeling approaches will be presented.

Conclusions: We demonstrate that ML-based pipelines can be developed for predicting HSBPV by utilizing SBP values generated from routine monitoring of ICH patients. Future development will incorporate streaming EMR SBP data points during patient stay, and evaluating high-dimensionality reduction methods such as principal component analysis.

Abstract TMP76: Direct Assessment of Health Utilities Among Patients With Intracerebral Hemorrhage Using the Standard Gamble Method

Introduction: EuroQoL-5 Dimension (EQ-5D) is a validated albeit indirect method to derive health utilities (HU). Conversely, Standard Gamble (SG) directly measures patients’ valuation of their health state. We compare in-hospital and day-90 SG Utilities (SGU) among intracerebral hemorrhage (ICH) patients and report a three-way association between SGU, EQ-5D and mRS at day-90.

Methods: Primary ICH patients were enrolled in a multisite cohort and underwent in-hospital and day-90 assessments for the mRS, EQ-5D, and SG. SG entails providing patients a choice between their current health state and a hypothetical treatment (a pill) with varying chances of either perfect health or a painless death. Higher SGU (scale 0 - 1) indicates a lower risk-tolerance for death; thus, a higher valuation of one’s health state. Median and interquartile range (IQR) are reported. Logistic regression was used to estimate the likelihood of low SGU (≤ 0.6) and Wilcoxson paired signed rank test compared in-hospital and day-90 SGU.

Results: In-hospital and day-90 SG was obtained from 381 and 280 patients respectively (including 236 paired observations). Median (IQR) in-hospital and day-90SGU were 0.85 (0.40-0.98) and 0.98 (0.75-1.00) (p < 0.001). In-hospital SGU were lower with advancing age (p = 0.007), with higher NIHSS and ICH scores (p < 0.001), and with greater treatment intensity. Proxies evaluated lower SGU (p < 0.001). In the adjustedmodel, higher NIHSS and proxy assessments were independently associated with lower SGU, along with an interaction between age and SGU by race (white vs. black) (Figure). Day-90 SGU and mRS were correlated (p < 0.001), however SGU were increasinglyhigher than the EQ-5D HU at higher mRS scores (Figure).

Conclusion: Divergence between directly and in-directly assessed HU at high levels of functional disability warrant careful prognostication of ICH outcomes, and should be considered in designing early end-of-life care discussions with families and patients.

Abstract WP489: Evaluation of Post-discharge Callback Data from Stroke Patients and Caregivers

Background and Purpose: The early period after hospital discharge is a critical time for stroke patients during which transitions of care can be optimized. In our Comprehensive Stroke Center, patients are called within 3 days of discharge to conduct point of service feedback utilizing yes/no and open-ended questions related to the hospital stay, discharge instructions, follow-up care, and prescriptions. We sought to examine post-discharge feedback to identify areas of need.

Methods: A multidisciplinary team collaborated to classify callback responses for patients discharged from 1/1/2018 to 6/30/2018 within the following domains from the Hospital Consumer Assessment of Healthcare Providers and Systems survey: care from doctors, care from nurses, hospital environment, experience in the hospital, and transitions of care. We provide a descriptive analysis (Table 1).

Results: Among 700 patients discharged in the study period, 378 (54%) were discharged home and 207 (55%) of these were contacted for feedback. Eighty four (40.5%) of patients/caregivers expressed at least one concern (129 total), with the largest proportion in the transitions of care domain (67.4 %). Patients reported difficulties with prescriptions (15.5%), obtaining outpatient therapy services (13.2%) and follow-up appointments (10.9%), new or persistent clinical symptoms (8.5%), and insufficient hospital discharge education (5.4%). Approximately 5% (11/207) of all patients reported hospital readmission during the call.

Conclusions: This study reveals that stroke patients and caregivers identify transitional care as an area for improvement following discharge from a CSC. Interventions aimed at facilitating care from hospital to home after stroke are warranted, and we are implementing patient-centered initiatives to enhance the discharge process and provide additional support early after stroke discharge.

Abstract WMP99: In-Hospital Delirium and Long-Term Cognitive Outcomes Among Patients With Intracerebral Hemorrhage: A Population-Based Cohort Analysis

Introduction: Little is known regarding the association between acute in-hospital exposures such as delirium and long-term cognitive outcomes in intracerebral hemorrhage (ICH) patients. We sought to explore the risk of mild cognitive impairment or dementia (MCID) among ICH patients who experienced in-hospital delirium.

Methods: We utilized State Inpatient and Emergency Department Databases for NY (2006 - 2014), CA (2005 - 2011), and FL (2005 - 2014), and established a cohort by selecting MCID free patients with a primary diagnosis of ICH (ICD-9: 431) during a 2yr period. Patients with concurrent diagnoses of head trauma, arteriovenous malformation or missing linkage information were excluded. Delirium during the initial ICH event was tagged using a validated algorithm with high specificity for the confusion assessment method. The cohort was followed for MCID diagnoses. Patients that died within 90 days of ICH were excluded. We conducted time-to-event analyses and report cumulative incidence, 95% Confidence Interval (CI) and hazard ratios (HR) for risk of MCID among ICH patients with and without delirium.

Results: A total of 18,083 ICH patients (age: 67.2, female: 47.6%, white: 59.1%) were included and were followed for up to 8yrs, resulting in 42,100 person-years. Patients who experienced delirium had a significantly higher comorbidity index and intensity of in-hospital treatment. Cumulative incidence (95% CI) for development of MCID was significantly higher among delirium patients (6.07, 5.05 - 7.30) as compared to non-delirium patients (4.07, 3.87 - 4.27). Likewise, the HR for MCID among delirium patients was statistically significant (1.42, 1.17 - 1.73) in the fully adjusted Cox proportional model (Figure).

Conclusion: ICH patients with in-hospital delirium are at a significantly higher risk of developing MCID. Further investigation is warranted to understand the mechanism for cognitive decline among ICH patients who experience in-hospital delirium.

Abstract TP462: Recruitment of African Americans in Blood Pressure Reduction Trials for Secondary Stroke Prevention

Background and Purpose: Reductions in blood pressure (BP) after stroke are associated with dramatic reductions in stroke risk. African Americans (AA) have higher risk of recurrent stroke than Whites and higher rates of uncontrolled BP after stroke. Prior studies have shown under-representation of minorities in secondary prevention trials. We identified studies of BP control for secondary stroke prevention and explored minority representation in the trials.

Methods: Relevant MeSH headings were used to conduct a PubMed search of randomized trials for secondary prevention of ischemic and hemorrhagic stroke and TIA, focused on BP reduction. We included studies published 1998 to 2018 that included participants from the US. We categorized articles according to timing post stroke, stroke type, intervention type, race/ethnic distribution, and mentioned efforts to increase minority proportions.

Results: Of 703 abstracts identified from PubMed, 42 studies were retained, and 8 met criteria after manuscript review. Six were US based and 2 international. All included ischemic stroke and/ or TIA patients. None focused on hemorrhagic stroke. Six trials included behavioral modification as a component of the intervention. Enrollment period ranged from 0 to 180 days post-stroke. For US based studies, 5 reported AA race (race reporting complete for 3 studies). The proportion of AA participants ranged from 8.4% to 41.5% Three studies recruited from diverse populations. There was no specific mention of oversampling of AAs in any trial.

Conclusion: Despite strong data to support BP reduction after stroke, there is a lack of US-based studies for secondary stroke prevention. More studies of BP control interventions to test medications and behavioral strategies for secondary stroke prevention in diverse patient populations are urgently needed.

Abstract WP53: Is There Clinicial Equipoise for a Randomized Trial of Anesthesia (Sedation vs. General) During Endovascular Therapy?

Background and Objectives: Retrospective case-control studies found general anesthesia (GA), compared with conscious sedation (CS), was independently associated with poor clinical outcome in acute ischemic stroke (AIS) patients receiving endovascular therapy (EVT). Conversely, recent randomized clinical trials (RCT) not only failed to demonstrate such an association, but also provided a trend toward better outcomes in GA vs. CS. We sought to describe EVT-anesthesia clinical practice and determine if clinical equipoise existed for the purposes of designing a large RCT.

Methods: We sent an online survey to 193 SVIN (Society of Vascular Interventional Neurology) and 78 AANS-CV (American Association of Neurological Surgeons - Cerebrovascular section) physicians that routinely perform EVT. Neurointerventionalists were asked a series of questions to describe their clinical practice, determine if clinical equipoise existed for designing a large GA vs. CS RCT and enthusiasm for trial participation.

Results: Between 3/17 and 5/17, 116 (60%) responses were received. The majority of centers had at least 3 or more interventionalists and performed at least 50 EVT procedures yearly (Table). Only 13% of respondents reported the use of GA in at least half of their EVT cases (Figure). While anesthesiologists in nearly all cases managed GA, neurointerventionalists administered CS in almost half of cases. 55% vs.45% of respondents thought a RCT was or was not necessary, respectively (Figure).

Conclusion: Anesthesia management during EVT varies widely and substantial uncertainty among experts demonstrates clinical equipoise. A large efficacy RCT is warranted, justified and underway (SEdation vs General Anesthesia for Endovascular Therapy in Acute Ischemic Stroke [SEGA Trial] Clinicaltrials.gov NCT-03263117).

Abstract WP77: Automated Accurate Determinations of Acute Infarct Core Volumes From CT Angiography Using Machine Learning

Background: Guideline-based acute ischemic stroke (AIS) evaluations require the use of advanced parenchymal imaging including CT perfusion (CTP) to determine the presence of large vessel occlusion (LVOs) and infarct core. The availability of CTP in all hospitals that receive patients with possible AIS is limited. An accurate method to evaluate possible AIS patients that does not require CTP is urgently needed.

Methods: Consecutive patients from 3/2018 - 5/2018 evaluated emergently for possible AIS within 24 hours of onset at our institution were identified. Patients were included if they underwent contemporaneous non-contrast CT, CT angiogram (CTA) and CT Perfusion (CTP) with RAPID (IschemaView) post-processing. A linear Support Vector Machine (SVM) was created using CTA data alone and trained against the CTP-RAPID infarct core volume determinations, which was used as the “gold standard.” Performance parameters were calculated using 10-fold cross-validation.

Results: Among 139 subjects, median age was 64 [54-73], 48% were female, 40% were white and 34% were African-American. From this population, 16 subjects (12%) were ultimately diagnosed with AIS. Median time from onset to imaging was 3.9 hours [1.7-10.1], NIHSS 16.5 [8-24], and RAPID infarct core and “at risk” volumes were 35.5 mL [13-72] and 128.5 mL [80-165]. The CTA-based SVM classified AIS versus stroke mimic with excellent discrimination (AUC 0.95 ± 0.08) and accuracy of 89% ± 3%. In patients with AIS, CTA-based SVM estimation of infarct core correlated well with the CTP-RAPID (Spearman's rho 0.82 (p<0.001) and Figure ).

Conclusion: Our machine learning algorithm was able to accurately discriminate AIS versus stroke-mimic, and reproduce CTP-based infarct core measurements from CTA imaging alone. A complete AIS neuroimaging evaluation, for LVO as well as infarct core, may be obtainable from CTA, an imaging modality with much broader availability than CTP.

Abstract TMP5: Social Media Campaign with Traditional Community Consultation for Successful Exception from Informed Consent Approval - the SEGA Trial Experience

Introduction/Background: Patients with severe stroke deficits due to large vessel occlusion are unable to provide consent and thus routinely excluded from emergency research participation – breaching the ethical principle of justice. The Food and Drug Administration has issued regulations for Exception from Informed Consent (EFIC) to facilitate research on potentially life-saving interventions in emergencies. We describe our novel approach to EFIC approval for an ongoing randomized trial that compares two anesthetic modalities for endovascular therapy (EVT) – sedation versus general anesthesia – the SEGA trial (Clinicaltrials.gov NCT-03263117).

Methods: Partnering with our Institutional Review Board (IRB), we used a multifaceted approach to inform the Houston, Texas metropolitan area about EFIC in SEGA. In addition to in-person community consultations and surveys with focus groups (stroke survivors, advisory councils, etc.), we created a novel social media campaign on Facebook to users ≥ 25 years old within a 50-mile radius from the Texas Medical Center. Advertisements linked to a university-created SEGA trial website that included details on EFIC regulations, trial aims, survey questions, and opt-out procedures. A press release was issued with information about the trial and links to the webpage.

Results: Between 6/17-9/17, we held 7 community consultations, placed Facebook ads, and issued a press release with trial information and website. Total of 193 individuals (65% female; average age 46.7 ± 16.6) participated in focus group community consultations. Of the 144 (75%) that completed surveys, 98% agreed to have themselves or a family member enrolled in SEGA under EFIC. Facebook ads had 134,481 views (52% female; 60% ≥ 45 years old) followed by 1,630 clicks to learn more and 1,130 website views (56% regional and 44% national). Users spent an average of 3 minutes and 51 seconds on the webpage. The IRB received zero emails requesting additional information or to opt-out.

Conclusion: Our novel community consultation method reached far more potential stroke patients than traditional in-person EFIC focus groups. We propose this method as a standard practice for trials seeking such approval.

High in-hospital blood pressure variability and severe disability or death in primary intracerebral hemorrhage patients

OBJECTIVE

To quantify in-hospital systolic blood pressure variability among patients with intracerebral hemorrhage, determine the association between high systolic blood pressure variability (HSBPV) and 90-day severe disability or death, and examine the association between pre-hospital factors and HSBPV.

METHODS

Adult, radiologically confirmed, intracerebral hemorrhage patients enrolled in a multi-site cohort were included. Using a semi-automated algorithm, systolic blood pressure values recorded from routine non-invasive systolic blood pressure monitoring in critical and acute care settings were extracted for the duration of hospitalization. Inter and intra-patient systolic blood pressure variability was quantified using generalized estimating equation methods. Modified Poisson and logistic regression models were fit to determine the association between HSBPV and 90-day severe disability or death and between pre-hospital characteristics and HSBPV, respectively.

RESULTS

A total of 566 patients managed at four certified stroke centers were included. Over 120,000 systolic blood pressure readings were analyzed, and a standard deviation (SD) of 13.0 was parameterized as a cut-off point to categorize HSBPV. Patients with HSBPV had a greater risk of 90-day severe disability or death (relative risk: 1.20, 95% confidence interval: 1.04-1.39), after controlling for age, pre-morbid functional status, and other disease severity measures. Greater likelihood of in-hospital HSBPV was independently observed in elderly, female patients, and in patients with high admission systolic blood pressure.

CONCLUSION

Quantification of HSBPV is feasible utilizing routinely collected systolic blood pressure readings, and a singular cut-off parameter for systolic blood pressure variability demonstrated association with 90-day severe disability or death. Elderly, female, and patients with high admission systolic blood pressure may be more likely to demonstrate HSBPV during hospitalization.

Cognitive deficits in acute mild ischemic stroke and TIA and effects of rt-PA

Introduction

It is unknown if treatment with rt-PA in mild acute ischemic stroke (MIS) is associated with improvement in long term cognition.

Methods

Forty-five patients with suspected acute mild stroke or transient ischemic attacks with NIHSS ≤6 were enrolled in a prospective cohort. Cognitive testing was performed within 24 h of symptom onset. Follow-up assessment was performed at Day 90 on 25 patients. Prestroke baseline cognition was based on age, years of education (YrE), history of cognitive impairment, and the Fazekas score.

Results

Eighty-five percent patients with suspected MIS or TIA showed cognitive abnormalities within 24 h of onset. There was no significant difference in age, sex, Fazekas score, or YrE between rt-PA versus No-rt-PA groups (N = 8 vs. 17).Two sample t-test for change in performance in the WMS-III sub-tests (follow-up - baseline) ± SD, indicated a difference between rt-PA 0.74 ± 0.77 and no-rt-PA groups -0.02 ± 0.83 (P = 0.044). Logistic regression for predicting normal status using the mental control subtest, at follow-up showed an OR 8.96, CI 0.98-82.12 (P = 0.05) favoring the rt-PA group. Improvement in Mental Control at 90 days occurred in patients with low white matter disease compared to high white matter disease, 0.60 ± 0.46 (P = 0.048). A statistical trend was observed and suggested an improvement on SDMT and Trail Making tests, 1.43 ± 0.8 (P = 0.077).

Conclusion

Suspected MIS and TIA patients have cognitive impairment within 24 h of onset. rt-PA administration might be associated with improvement on some cognitive tests at 90 days.

No Weekend or After-Hours Effect in Acute Ischemic Stroke Patients Treated by Telemedicine

BACKGROUND

Stroke outcomes have been shown to be worse for patients presenting overnight and on weekends (after-hours) to stroke centers compared with those presenting during business hours (on-hours). Telemedicine (TM) helps provide evaluation and safe management of stroke patients. We compared time metrics and outcomes of stroke patients who were assessed and received intravenous recombinant tissue plasminogen activator (IV-tPA) via TM during after-hours with those during on-hours.

METHODS

Analysis of our TM registry from September 2015 to December 2016, identified 424 stroke patients who were assessed via TM and received IV-tPA. We compared baseline characteristics, clinical variables, time metrics, and outcomes between the after-hours (5 pm-7:59 am, weekends) and on-hours (weekdays 8 am-4:59 pm) patients.

RESULTS

Of the 424 patients, 268 were managed via TM during after-hours, and 156 during on-hours. Baseline characteristics and clinical variables were similar between the groups. Importantly, there were no differences in all relevant time metrics including door to IV-tPA bolus time. IV-tPA complications (including all intracerebral hemorrhage (ICH), any systemic bleeding, and angioedema), discharge disposition, and 90-day modified Rankin Scale were also similar in the groups.

CONCLUSIONS

There was no difference in IV-tPA treatment times, acute stroke evaluation times, or mortality between the patients treated after-hours versus on-hours. Unlike in-person neurology coverage at many centers, the coverage provided by TM does not differ depending on the hour or day. Access to stroke specialists 24/7 via TM can ensure dependable and timely clinical care for acute stroke patients regardless of the time of day or day of the week.