Protective Effects of Autologous Bone Marrow Mononuclear Cells After Administering t-PA in an Embolic Stroke Model

Tissue plasminogen activator (t-PA) is the only FDA-approved drug for acute ischemic stroke but poses risk for hemorrhagic transformation (HT). Cell therapy has been investigated as a potential therapy to improve recovery after stroke by the modulation of inflammatory responses and the improvement of blood-brain barrier (BBB) integrity, both of which are associated with HT after t-PA. In our present study, we studied the effect of autologous bone marrow mononuclear cells (MNCs) in an embolic stroke model. We administered MNCs in a rat embolic stroke 2 h after administering t-PA. We observed that even though autologous MNCs did not alter the incidence of HT, they decreased the severity of HT and reduced BBB permeability. One possible mechanism could be through the inhibition of MMP3 released by astrocytes via JAK/STAT pathway as shown by our in vitro cell interaction studies.

Nationwide Estimates of 30-Day Readmission in Patients With Ischemic Stroke

Background and Purpose—

Readmission within 30 days of hospital discharge for ischemic stroke is an important quality of care metric. We aimed to provide nationwide estimates of 30-day readmission in the United States, describe important reasons for readmission, and sought to explore factors associated with 30-day readmission, particularly the association with recanalization therapy.

Methods—

We conducted a weighted analysis of the 2013 Nationwide Readmission Database to represent all US hospitalizations. Adult patients with acute ischemic stroke including those who received intravenous tissue-type plasminogen activator and intra-arterial therapy were identified using International Classification of Diseases -Ninth Revision codes. Readmissions were defined as any readmission during the 30-day post-index hospitalization discharge period for the eligible patient population. Proportions and 95% confidence intervals for overall 30-day readmissions and for unplanned and potentially preventable readmissions are reported. Survey design logistic regression models were fit for determining crude and adjusted odds ratios and 95% confidence interval for association between recanalization therapy and 30-day readmission.

Results—

Of the 319 317 patients with acute ischemic stroke, 12.1% (95% confidence interval, 11.9–12.3) were readmitted. Of these, 89.6% were unplanned and 12.9% were potentially preventable. More than 20% of all readmissions were attributable to acute cerebrovascular disease. Readmitted patients were older and had a higher comorbidity burden. After controlling for age, sex, insurance status, and comorbidities, patients who underwent recanalization therapy had significantly lower odds of 30-day readmission (odds ratio, 0.82; 95% confidence interval, 0.77–0.89).

Conclusions—

Up to 12% of patients with ischemic stroke get readmitted within 30 days post-discharge period, and recanalization therapy is associated with 11% to 23% lower odds of 30-day readmission.

Treatment of Severe Adult Traumatic Brain Injury Using Bone Marrow Mononuclear Cells

Preclinical studies using bone marrow derived cells to treat traumatic brain injury have demonstrated efficacy in terms of blood-brain barrier preservation, neurogenesis, and functional outcomes. Phase 1 clinical trials using bone marrow mononuclear cells infused intravenously in children with severe traumatic brain injury demonstrated safety and potentially a central nervous system structural preservation treatment effect. This study sought to confirm the safety, logistic feasibility, and potential treatment effect size of structural preservation/inflammatory biomarker mitigation in adults to guide Phase 2 clinical trial design. Adults with severe traumatic brain injury (Glasgow Coma Scale 5-8) and without signs of irreversible brain injury were evaluated for entry into the trial. A dose escalation format was performed in 25 patients: 5 controls, followed 5 patients in each dosing cohort (6, 9, 12 ×106 cells/kg body weight), then 5 more controls. Bone marrow harvest, cell processing to isolate the mononuclear fraction, and re-infusion occurred within 48 hours after injury. Patients were monitored for harvest-related hemodynamic changes, infusional toxicity, and adverse events. Outcome measures included magnetic resonance imaging-based measurements of supratentorial and corpus callosal volumes as well as diffusion tensor imaging-based measurements of fractional anisotropy and mean diffusivity of the corpus callosum and the corticospinal tract at the level of the brainstem at 1 month and 6 months postinjury. Functional and neurocognitive outcomes were measured and correlated with imaging data. Inflammatory cytokine arrays were measured in the plasma pretreatment, posttreatment, and at 1 and 6 month follow-up. There were no serious adverse events. There was a mild pulmonary toxicity of the highest dose that was not clinically significant. Despite the treatment group having greater injury severity, there was structural preservation of critical regions of interest that correlated with functional outcomes. Key inflammatory cytokines were downregulated. Treatment of severe, adult traumatic brain injury using an intravenously delivered autologous bone marrow mononuclear cell infusion is safe and logistically feasible. There appears to be a treatment signal as evidenced by central nervous system structural preservation, consistent with previous pediatric trial data. Inflammatory biomarkers are downregulated after cell infusion. Stem Cells 2016 Video Highlight: https://youtu.be/UiCCPIe-IaQ Stem Cells 2017;35:1065-1079.

Video-based educational intervention associated with improved stroke literacy, self-efficacy, and patient satisfaction

Background and purpose

Interventions are needed to improve stroke literacy among recent stroke survivors. We developed an educational video for patients hospitalized with acute ischemic stroke (AIS) and intracerebral hemorrhage (ICH).

Methods

A 5-minute stroke education video was shown to our AIS and ICH patients admitted from March to June 2015. Demographics and a 5-minute protocol Montreal Cognitive Assessment were also collected. Questions related to stroke knowledge, self-efficacy, and patient satisfaction were answered before, immediately after, and 30 days after the video.

Results

Among 250 screened, 102 patients consented, and 93 completed the video intervention. There was a significant difference between pre-video median knowledge score of 6 (IQR 4–7) and the post-video score of 7 (IQR 6–8; p<0.001) and between pre-video and the 30 day score of 7 (IQR 5–8; p = 0.04). There was a significant difference between the proportion of patients who were very certain in recognizing symptoms of a stroke pre- and post-video, which was maintained at 30-days (35.5% vs. 53.5%, p = 0.01; 35.5% vs. 54.4%, p = 0.02). The proportion who were “very satisfied” with their education post-video (74.2%) was significantly higher than pre-video (49.5%, p<0.01), and this was maintained at 30 days (75.4%, p<0.01). There was no association between MoCA scores and stroke knowledge acquisition or retention. There was no association between stroke knowledge acquisition and rates of home blood pressure monitoring or primary care provider follow-up.

Conclusions

An educational video was associated with improved stroke knowledge, self-efficacy in recognizing stroke symptoms, and satisfaction with education in hospitalized stroke patients, which was maintained at 30 days after discharge.

Safety and efficacy of multipotent adult progenitor cells in acute ischaemic stroke (MASTERS): a randomised, double-blind, placebo-controlled, phase 2 trial

BACKGROUND

Multipotent adult progenitor cells are a bone marrow-derived, allogeneic, cell therapy product that modulates the immune system, and represents a promising therapy for acute stroke. We aimed to identify the highest, well-tolerated, and safest single dose of multipotent adult progenitor cells, and if they were efficacious as a treatment for stroke recovery.

METHODS

We did a phase 2, randomised, double-blind, placebo-controlled, dose-escalation trial of intravenous multipotent adult progenitor cells in 33 centres in the UK and the USA. We used a computer-generated randomisation sequence and interactive voice and web response system to assign patients aged 18-83 years with moderately severe acute ischaemic stroke and a National Institutes of Health Stroke Scale (NIHSS) score of 8-20 to treatment with intravenous multipotent adult progenitor cells (400 million or 1200 million cells) or placebo between 24 h and 48 h after symptom onset. Patients were ineligible if there was a change in NIHSS of four or more points during at least a 6 h period between screening and randomisation, had brainstem or lacunar infarct, a substantial comorbid disease, an inability to undergo an MRI scan, or had a history of splenectomy. In group 1, patients were enrolled and randomly assigned in a 3:1 ratio to receive 400 million cells or placebo and assessed for safety through 7 days. In group 2, patients were randomly assigned in a 3:1 ratio to receive 1200 million cells or placebo and assessed for safety through the first 7 days. In group 3, patients were enrolled, randomly assigned, and stratified by baseline NIHSS score to receive 1200 million cells or placebo in a 1:1 ratio within 24-48 h. Patients, investigators, and clinicians were masked to treatment assignment. The primary safety outcome was dose-limiting toxicity effects. The primary efficacy endpoint was global stroke recovery, which combines dichotomised results from the modified Rankin scale, change in NIHSS score from baseline, and Barthel index at day 90. Analysis was by intention to treat (ITT) including all patients in groups 2 and 3 who received the investigational agent or placebo. This study is registered with ClinicalTrials.gov, number NCT01436487.

FINDINGS

The study was done between Oct 24, 2011, and Dec 7, 2015. After safety assessments in eight patients in group 1, 129 patients were randomly assigned (67 to receive multipotent adult progenitor cells and 62 to receive placebo) in groups 2 and 3 (1200 million cells). The ITT populations consisted of 65 patients who received multipotent adult progenitor cells and 61 patients who received placebo. There were no dose-limiting toxicity events in either group. There were no infusional or allergic reactions and no difference in treatment-emergent adverse events between the groups (64 [99%] of 65 patients in the multipotent adult progenitor cell group vs 59 [97%] of 61 in the placebo group). There was no difference between the multipotent adult progenitor cell group and placebo groups in global stroke recovery at day 90 (odds ratio 1·08 [95% CI 0·55-2·09], p=0·83).

INTERPRETATION

Administration of multipotent adult progenitor cells was safe and well tolerated in patients with acute ischaemic stroke. Although no significant improvement was observed at 90 days in neurological outcomes with multipotent adult progenitor cells treatment, further clinical trials evaluating the efficacy of the intervention in an earlier time window after stroke (<36 h) are planned.

FUNDING

Athersys Inc.

Multipotent Adult Progenitor Cells Enhance Recovery After Stroke by Modulating the Immune Response from the Spleen

Stem cell therapy modulates not only the local microenvironment of the brain but also the systemic immune responses. We explored the impact of human multipotent adult progenitor cells (MAPC) modulating splenic activation and peripheral immune responses after ischemic stroke. Hundred twenty-six Long-Evans adult male rats underwent middle cerebral artery occlusion. Twenty-four hours later, they received IV MAPC or saline treatment. At 3 days after infusion, RNA was isolated from the injured cortex and spleen for microarray analysis. Spleen mass, splenocyte phenotype, and releasing cytokines were measured. Serum cytokines, MAPC biodistribution, brain lesion sizes and neurofunctional deficits were compared in rats treated with MAPC or saline with and without spleens. Stroked animals treated with MAPC exhibited genes that more closely resembled animals with sham surgery. Gene categories downregulated by MAPC included leukocyte activation, antigen presentation, and immune effector processing, associated with the signaling pathways regulated by TNF-α, IL-1β, IL-6, and IFN-γ within the brain. MAPC treatment restored spleen mass reduction caused by stroke, elevated Treg cells within the spleen, increased IL-10 and decreased IL-1β released by splenocytes. MAPC reduced IL-6 and IL-1β and upregulated IL-10 serum levels. Compared with saline, MAPC enhance stroke recovery in rats with intact spleens but had no effects in rats without spleens. MAPC restores expression of multiple genes and pathways involved in immune and inflammatory responses after stroke. Immunomodulation of the splenic response by the intravenous administration of MAPC may create a more favorable environment for brain repair after stroke. Stem Cells 2017;35:1290-1302.

Abstract TP232: Disparities in Access to Stroke Research in the State of Texas

Objective: Access to care is an important healthcare goal but access to research is also important to patients. We sought to gain an understanding of the status of stroke research among the various stroke designated hospitals in the state and to identify regions and facilities that lack access to stroke research.

Methods: Texas Department of State Health Service (TDSHS) designated stroke facilities (DSF) were surveyed using a standardized questionnaire via telephone/email to confirm stroke center status, presence of a dedicated stroke coordinator, use of telestroke services, and participation in stroke research. Stroke discharge data were obtained from TDSHS and stroke volume (by ICD) were estimated for 2013 for all non-DSF. Census data were obtained from the US Census Bureau.

Results: In total, 109/136 (80%) TDSHS DSF responded to the survey. Only 32/109 (29%) of the TDSHS DSF are participating in stroke research, mostly in the 4 metropolitan areas (fig 1). We identified 16 non-DSF that have 100-149 stroke discharges, and another 21 non-DSF that have ≥ 150 stroke discharges (fig 1). Over half (53%) of the DSF in the state are utilizing telestroke services.

Conclusions: Most clinical stroke research conducted in Texas is in the 4 metropolitan markets. Our findings demonstrate that over 50% or ~14 million Texans reside outside of the 4 markets and therefore may lack access to stroke research. To increase access, we identified several non-DSF in the state with substantial stroke discharges (fig 1). Academic centers and non-DSF partnering through telemedicine and other relationships should be considered to expand throughout the state opportunities for participation in stroke research.

Abstract WP271: Door to Page Time to Initiate a Telemedicine Consult Varies Among Spoke Hospitals for Acute Stroke

Introduction: Although telemedicine (TM) has increased tPA use for acute ischemic stroke (AIS), there are delays between when an AIS patient enters the ED and when the TM consultant is paged. We identified predictors of delayed door-to-page time (DTP) for AIS patients evaluated on TM.

Hypothesis: We investigated spoke characteristics associated with the time between patient arrival and the TM code stroke page.

Methods: We identified suspected AIS patients in our telestroke registry who were evaluated by video consultation at one of 15 spoke hospitals within six hours of symptom onset (9/2015-3/2016). We compared DTP among spokes and identified factors associated with prolonged DTP.

Results: Median DTP was 22 minutes (12-38, Q1-Q3). Of 382 cases 44.0% had DTP ≤20 minutes and 13.5% >60 minutes (Figure). There was no significant difference in DTP among patients of different age, gender, race/ethnicity, and stroke severity (Table). Hospitals with fewer beds, no pre-notification protocols, location in a medically underserved area (MUA), and less in-house neurology availability had delayed DTP.

Conclusions: Bed capacity, pre-notification, location in a MUA, and in-house neurology availability are associated with prolonged DTP. While retrospective in nature, our study confirms the utility of pre-notification for spoke hospitals. Further investigation is needed to understand why smaller hospitals and spokes in a MUA have longer DTP, and how in-house neurology coverage affects DTP. In addition, standardized acute stroke metrics over TM are needed.

Abstract WP307: Lone Star Stroke Consortium TeleStroke Registry (LESTER)

Background: The Lone Star Stroke Consortium TeleStroke Registry (LESTER) currently consisting of 3 academic hub centers and 25 partner spokes is a statewide initiative organized by UTHealth to understand practice patterns of acute stroke management via telemedicine (TM) in Texas, a state with one of the largest rural populations in the US.

Methods: All presumed stroke patients for whom a TM consultation has been obtained in the network are entered into a web-based, HIPAA-compliant database from 9/2013 to 3/2016. 90-day mRS and disposition are obtained by a standard phone interview.

Results: A total of 3390 TM consults were performed: 57.3% acute ischemic stroke (AIS); 8.6% TIA; 1.4% ICH; 32.3% non-stroke related diagnoses (Table). Half of the cases were < 65 years of age. Overall 38.3% of AIS cases received tPA and 12.5% of all cases were transferred to a hub. tPA rates varied from 19% to 50% and transfer rates varied from 0% to 37.5% among spokes with at least 10 AIS consults.

Conclusions: In this statewide registry of telestroke organized by academic health centers, TM leads to substantially high rates of tPA administration for AIS cases compared with national treatment rates in the US. TM provided by academic centers also leads to low rates of transfer from spoke hospitals, suggesting improvement in allocation of healthcare resources.

Abstract TMP40: Sociodemographic Predictors of Return to Home after Inpatient Stroke Rehabilitation

Background: Interpersonal relationships are understudied components of the stroke treatment paradigm, which become important when patients require long-term care. In this study, we analyzed sociodemographic factors that impact return to home after inpatient rehabilitation (IR).

Methods: Stroke patients were identified by ICD9/10 code from a prospective multicenter rehabilitation registry between Jan 2005 & July 2016 (n=6447). Patients were analyzed based upon "Home" vs "Not Home" or "Married" vs "Not Married" groups. Descriptive statistics were provided for all patients. Marital status was used as a proxy for caregiver support. We hypothesized that increased discharge functional independence measure (FIM), ambulation and no insurance predicted return to home. A “return home model” was developed using multivariable regression with a stepwise approach. Odds ratio & 95% CI were calculated.

Results: 5378 patients returned Home, 1069 did not return Home. Home patients tended to be younger, married, ambulatory and minorities, with a discharge FIM>75 (p<0.0001). Aphasia, dysphagia and UTI were significantly higher in the “Not Home” group (p<0.0001). Married patients had more stroke risk factors and impairments, indicating increased caregiver needs (Figure). In the model, being a minority and being a woman increased the odds of returning home. Advancing age, being widowed, divorced, separated or never married decreased the odds of returning home. We confirmed that ambulation, increasing discharge FIM and no insurance predicted return to home (Figure).

Conclusions: Being married, a woman or a minority increases the odds of returning home after inpatient rehabilitation. Caregiver training and social support for unmarried and male patients are important areas of improvement. Strategies to ensure the successful transition of stroke rehabilitation patients to home are needed, including prospective studies of non-spousal caregiver support.

Abstract TMP78: Time From Consult Page to Tissue Plasminogen Activator Treatment Over Telestroke Decreases With Experience

Introduction: Formal telestroke (TS) training for neurovascular fellows (NVFs) is necessary due to growing gaps in acute ischemic stroke (AIS) coverage, yet educational approaches are not well-characterized. Time between when a TS consultant is paged and tPA administration (page-to-needle time, PTNT) can provide an objective measure of proficiency in TS management of AIS.

Hypothesis: We hypothesized that NVFs have longer PTNT than neurovascular attendings (NVAs), and PTNT improves with increasing number of TS consults.

Methods: We identified suspected AIS patients in our TS registry (7/2013-6/2016) who received tPA while being evaluated remotely by video consultation at one of 17 spokes. Using multivariable quantile regression, we estimated the difference, and 95% confidence interval (CI) of the difference, for median PTNT between NVFs and NVAs. We also report the coefficient of change in PTNT over increasing number of TS consults.

Results: Table 1 depicts baseline characteristics. NVFs evaluated 53.7% of 618 tPA cases over TS. NVAs took less time to administer tPA, difference in median PTNT (95% CI): -9 min (-12.3 to -5.7). This difference persisted when adjusted for relative tPA contraindications. For each additional TS consult, PTNT was decreased by 0.07 min for NVFs or NVAs (p=0.02 and <0.01, respectively) (Figure 1).

Conclusion: TPA metrics improve with increasing number of TS consults for NVFs and NVAs. PTNT improves by 1 min for approximately every 14 TS consults. Our findings support the importance of integrating TS training into a supervised neurovascular fellowship to increase NVF proficiency in TS prior to independent practice.

Abstract TMP73: Intra-arterial Transfer Time Metrics Study—Southern California Kaiser Permanente and University of Texas Houston Telestroke Network Experience

Background: The transfer process for patients with large vessel occlusions from a community hospital to an intra-arterial therapy (IAT)-capable center often involves multiple teams of physicians and administrative personnel, leading to delays in care.

Objective We compared time metrics for spoke drip-and-ship telemedicine (TM) patients transferred for IAT to comprehensive stroke centers (CSC) in two different health systems: Kaiser Permanente (KP) with an integrated health care system of spokes and a 50 mile range using ambulances for transfer vs UTHealth (UTH), where patients are transferred by helicopter from varying health systems ranging up to 200 miles from the hub.

Methods: We retrospectively identified patients in the KP and UTH networks transferred from TM spokes to the CSC (KP—6 spokes and UTH -17 spokes). From 9/15 to 4/16, a total of 79 TM patients (KP-28 patients, UTH-51 patients) were transferred to the respective hubs for evaluation of IAT. Baseline clinical data, transfer, and IAT metrics were abstracted.

Results: On average, it takes ~90 minutes for a TM patient to arrive at the CSC hub once accepted by the transfer center. Patients in the KP Network arrive at the hub faster than UTH patients, but IAT metrics/outcomes are comparable. Over 50% of the patients did not undergo IAT on hub arrival mostly due to lack of clot on CTA (20/45) or symptom improvement (9/45).

Conclusion: In two large, yet different TM networks, the transfer time from spoke to hub needs to be shortened. Areas for improvement include spoke arrival to transfer acceptance and transfer acceptance to hub arrival. A prospective study is underway to develop best practice time parameters for this complex process of identifying and transferring patients eligible for IAT.

Abstract WP5: The Transfer Score May Aid Decisions Whether to Transfer Patients with Large Vessel Occlusions for Endovascular Therapy

Background: While faster reperfusion with EVT leads to better outcomes in acute ischemic stroke due to large vessel occlusion (LVO), most LVO patients present to outside hospitals without EVT capability. Treating physicians are often unsure if EVT would confer benefit upon arrival to tertiary hospitals given inter-facility transfer delays.

Objective: We evaluated independent predictors of good outcome in transferred patients treated with EVT to devise a score that may assist treating physicians to make transfer and treatment decisions.

Methods: Transfer patients were analyzed in a multicenter international prospective cohort study of LVO patients treated with stent retriever thrombectomy (TREVO Registry) from 11/2013 to 4/2016. Independent factors correlating with good outcome after EVT were identified using univariate and multivariate analyses. We devised a score to identify patients with LVO at the referral facility who may benefit from EVT.

Results: Of 1000 patients enrolled, 226 were anterior circulation occlusions, transferred and treated within 0-8 hrs (Table 1). Age, stroke severity, glucose level, M2 occlusion and achieving onset to groin puncture ≤ 5 hr were independent factors associated with good outcome (Table 2). Other clinical variables were analyzed, as in ASPECTS, but were not significant. A 10 point score was devised (Table 3). Patients with a score of 0-4 had 4 times the odds of good outcome compared to a score of 5-9 (aOR 4.3, 95% CI 1.9-9.9; p <0.001). These results were maintained after adjustment for mTICI and IV-tPA (aOR 4.0, 95% CI 1.7-9.4; p <0.001). Fig 1 shows good outcome rates stratified by score points. ROC curves showed better score performance (AUC= 0.8) compared to THRIVE (AUC=0.74) and HIAT (AUC=0.69) certifying good predictability.

Conclusion: A simple transfer score may be an effective triage method to identify patients at remote facilities who may benefit from EVT upon transfer. Further validation is necessary to confirm these findings.

Abstract 155: Bone Marrow Mononuclear Cells Enhance Stroke Recovery Through the Release of Fractalkine From the Spleen

Background: Some types of cell-based therapies may reduce secondary brain injury after stroke by modulating immune responses from the spleen. Here, we hypothesized that fractalkine (FKN; CX3CL1) derived from the spleen mediates cross-talk between the spleen and brain, and that upregulation of FKN in the spleen by bone marrow mononuclear cells (MNCs) is an important mechanism underlying how MNCs enhance recovery after stroke.

Methods: To model ischemic stroke, we employed rat and mouse middle cerebral artery occlusion (MCAo) models. 24 hours after MCAo, animals received autologous MNCs IV or saline as vehicle controls. Brains and spleens were harvested and serum was collected at various time points after MCAo. FKN gene expression and protein levels were measured. Functional testing was evaluated for up to 28d after MCAo. In parallel experiments, mice were subjected to splenectomy two weeks prior to MCAo and the same experiments were repeated in animals without a spleen. In another experiment, antibody neutralizing FKN receptor (anti-CX3CR1) was injected ICV at 1 hour after MNC to evaluate the impact of blocking the FKN receptor in the brain.

Results: MNC treatment significantly increased FKN levels in the spleen, serum and brain starting 1 day after MNC treatment, as compared to the vehicle-treated group. Splenectomy significantly attenuated FKN upregulation in response to MNC administration, and also attenuated the treatment-mediated effects on functional recovery. ICV injection of anti-CX3CR1 also abolished the MNCs-mediated beneficial effect on stroke recovery. In cell culture experiment, MNCs increased soluble FKN release by spenocytes and this process required physical MNC-splenocyte interaction and was dependent on the presence of IFN-γ.

Conclusion: MNCs enhance stroke recovery through mechanisms involving the spleen; FKN may be one of the important signals mediating the cross-talk between the spleen and the brain.

Abstract TP348: Quantitative Serial Neuroimaging of Iron in the Intracerebral Hemorrhage Pig Model

Objective: To serially quantify changes of iron concentration within hematomas in the intracerebral hemorrhage (ICH) pig model using non-invasive R2* and quantitative susceptibility mapping (QSM) MRI methods.

Introduction: Hemolysis-related release of hemoglobin/heme/free iron after ICH causes cytotoxic injury. An accurate post hemorrhage assessment of iron would be valuable to develop strategies to prevent secondary damage. The T2* relaxation rate (R2* =1/T2*) on MRI depends on the regional oxy- versus deoxyhemoglobin. Post-ICH excess of deoxyhemoglobin has been applied as a quantitative marker to estimate iron in the brain. However, quantitative susceptibility mapping (QSM) is a new MRI technique that can quantify iron concentration within the hematoma by measuring induced magnetic susceptibility. Using R2* mapping and QSM in a large animal ICH model, we measured spatiotemporal changes in iron concentration in the brain.

Methods: Lobar ICH was induced by infusion of 2.5 ml autologous blood in 8 Yorkshire pigs with average age/wt of 4-6wk/12.5±2.5kg. MRI was obtained at days 1 and 7. A 3D anatomical and multi-echo gradient echo images were obtained on a clinical 3.0 T Philips Ingenia MRI system. Parametric R2* and susceptibility maps were generated. Regions of interest were placed within hematoma and contralesional CSF.

Results: R2* measurements in the hematoma at day 1 and day 7 were 41.3 ± 7.3 and 37.7 ± 7.7 s -1 , respectively, whereas the corresponding susceptibility measurements were 0.75± 0.3 and 0.70 ± 0.5 ppm. The CSF R2* were 5.53 ± 2.1 and 6.85 ± 2.4 s -1 , whereas susceptibility showed 0.06 ± 0.16 and 0.02 ± 0.03 ppm at the two time points. Both R2* and QSM showed no significant change in iron concentration within the hematoma ROI with p-value of 0.18 and 0.72 over a week. Absence of hyperintense regions remote from the hematoma in susceptibility maps suggested lack of diffuse iron deposition. Good correlation was observed between R2* and QSM (correlation coefficient 0.83 and 0.78 within hematoma, and -0.66 and -0.07 within CSF, at day 1 and 7, respectively).

Conclusion: R2* and especially QSM, with their ability to provide quantitative iron content, are valuable tools to test new ICH treatments particularly targeting iron in this large animal model.

Abstract TP94: Mesenchymal Stromal Cells Behave Differently When Exposed to Medications Commonly Prescribed to Stroke Patients

Background: As a promising investigational therapy for stroke recovery, mesenchymal stromal cells (MSCs) are in various stages of clinical trials. MSCs may promote recovery through cytokine release and immunomodulation. Stroke patients typically are treated with antiplatelets and medications for hypertension and hyperlipidemia. We explored the effect of commonly prescribed drugs at physiological concentrations on MSCs.

Methods: Clinical grade bone marrow MSCs from healthy donor at passage 2 were thawed and re-suspended in serum free media. Monocytes (Mo) were isolated from peripheral blood of healthy humans. MSCs and Mo were cultured alone as well as in co-culture and exposed to simvastatin, atenolol, losartan, captopril, or aspirin. They were also exposed to high glucose (upto 40mM) to simulate hyperglycemia. At 24 hours of incubation, media was collected and TNF-α concentration was measured, as an index of immunomodulation of Mo by MSCs. Cell viability was also measured (using MTT assay and flow cytometry).

Results: There were significant effects of all drugs on viability of MSCs but with no impact on Mo. More importantly, Losartan (dose independent), Simvastatin and Atenolol (dose-dependent) reduced the viability of MSCs even at the pharmacologically relevant concentrations (Fig 1). High glucose had no effect on viability of MSCs or Mo. TNF-α secretion from co-culture of MSCs and Mo at 24 hours showed differences at very high doses of aspirin (2-fold increase), atenolol (0.5 fold decrease), and glucose (0.5 fold decrease) (data not shown). However, these high concentrations are unlikely to be achieved pharmacologically in plasma of patients treated with these drugs.

Conclusion: Exposure of MSCs to clinically relevant drugs can alter their viability and function. Our results suggest that stroke trials involving use of intravenous MSCs should consider the differential impact of commonly prescribed medications on MSCs function.

Abstract TP151: Association of Splenic Contraction And Development of Systemic Inflammatory Response Syndrome After Acute Ischemic Stroke

Background: Animal models have demonstrated the deleterious contribution that immunocytes from the spleen exert on secondary brain injury after stroke. While previous work has demonstrated that there is splenic contraction (SC) in patients with acute ischemic stroke (AIS) and intracranial hemorrhage (ICH), no clinical studies have connected the systemic inflammatory response syndrome (SIRS) with SC. We aim to associate SIRS and its individual components with SC in acute stroke

Methods: This is a retrospective analysis of a previous prospective observational study where daily spleen sizes were evaluated in 178 acute stroke patients in a tertiary care center from 2010-2013. Spleen contraction was defined compared to previously established normograms of healthy volunteers from the same study. SIRS was defined as the presence of 2 or more of the following: body temperature <36 or >38C, heart rate >90 beats, respiratory rate >20, and serum white blood cell count >12,000 or <4000 mm3 in the absence of infection. SC was evaluated in patients at 24 and 72 hrs after AIS with SIRS as a primary outcome.

Results: 91 patients had verified AIS without concurrent infection at admission and 70 of these patients remained inpatient at 72 hrs. SIRS was not associated with admission SC at 24hr and 72 hrs. Patients with SIRS at 24 and 72 hrs were more likely to have higher admission NIHSS. SIRS was associated with higher discharge mRS (OR 4.24, 95% CI 1.64-10.9, p=0.0028) and PEG placement (OR 3.70, 95% CI 0.95-15.11, p=0.05). 16 patients (22.9%) developed SIRS by 72hrs, only 5 of whom had SC initially. 28 patients (47%) had SIRS on admission that persisted, 12 of whom had SC. SC was not associated with SIRS at 72 hrs (OR 1.05, 95% CI 0.35-2.79, p = 0.92). 14 patients (15%) developed infections while hospitalized, of which 85% had SIRS on admission.

Conclusion: Based on our initial evaluation, SC detected within 24 hrs of stroke onset is not associated with SIRS suggesting that the relationship between the two may be more complicated in humans. Consistent with prior studies, however, SIRS is associated with worse outcome. Further studies and additional time points are necessary to further clarify the role of the spleen in the development of SIRS in stroke patients.

Abstract WP305: Uniting Hospital Leaders in a Competitive Region to Improve Intravenous Thrombolysis Rates: Analysis of the SETRAC Stroke Registry

Uniting Hospital Leaders in a Competitive Region To Improve Intravenous Thrombolysis Treatment Rates: Analysis of the SETRAC Stroke Registry

Background: The Southeast Texas Regional Advisory Council (SETRAC) convenes representatives from area hospitals belonging to different health systems to discuss how to improve the delivery of stroke care in a nine county area that includes Houston, Texas. In 2014, area hospitals agreed to focus upon improving tissue plasminogen activator (tPA) administration rates in the area.

Hypothesis: By sharing stroke metrics in a blinded fashion on a consistent basis, tPA administration rates will improve. The theory was tested by tracking the following metrics:

a. percent of ischemic stroke patients receiving tPA.

b. percent of treated patients receiving tPA within 60 minutes of arrival at the hospital.

Methods: SETRAC aligned regional metrics with stroke treatment and timing metrics in Get With The Guidelines®-Stroke beginning in Q3 2014. SETRAC compiled and shared this data with stroke coordinators and hospital administrators on a quarterly basis. Bar graphs were utilized for benchmarking hospitals in a blinded fashion. Linear tests were performed to validate increases in the percent of patients treated with tPA and the percent of patients treated within 60 minutes of arrival at the hospital. Results from hospitals that consistently reported data for each of the six quarters were included in the analysis.

Results: Twenty-six area hospitals reported 10,396 ischemic stroke patients between Q3 2014 through Q4 2015. In that time, tPA administration increased from 10.3% in Q3 2014 to 12.0% in Q4 2015 (p<0.001). Further, tPA administration within 60 minutes of arrival in emergency room increased from 55.3% in Q3 2014 to 66.7% in Q4 2015 (p<0.001).

In conclusion, following the uniting of hospital leaders and utilizing nationally aligned stroke metrics, a higher percentage of ischemic stroke patients received tPA. Of those that received tPA, an improvement in the timeliness of administration was also realized.

Abstract WMP9: Endovascular Thrombectomy Impact in the First Three “Golden” Hours

Background: Endovascular thrombectomy (EVT) substantially increases the likelihood of good outcome in acute ischemic strokes due to large vessel occlusion (LVO). Expediting EVT to achieve faster reperfusion is an important factor that correlates with good outcome. Ultra-early intervention in the first 3 “golden” hours from onset was not well characterized in recent trials.

Objective: We sought to assess the impact of early treatment within the first 3 hours on clinical outcomes in large, real life, world-wide practice.

Methods: We analyzed a multicenter international prospective cohort study of LVO patients treated with stent retriever thrombectomy (TREVO Registry) between11/2013 and 4/2016. We stratified patients based on treatment time, onset to groin puncture (GP), into 3 groups: 0-3, 3-6, >6 hrs. 90 day mRS was the primary outcome (0-2 good outcome). Logistic regression modeling was performed to evaluate the impact of treatment within the golden 3 hours on outcomes and to determine the independent factors associated with EVT initiation within 3 hours.

Results: In the 905 patients, GP occurred in: 23.1% 0-3 hrs, 44.3% 3-6 hrs and 32.6% >6 hrs. Table 1 shows similar baseline characteristics among the groups. Patient-level predictors of treatment within 3 hrs were age (aOR 1.1 per decade of age ≥18) and good ASPECTS (aOR 1.2 per point). No hospital-level predictors of early treatment were found. Patients treated within 3 hrs have a higher likelihood of good outcome as compared to those treated >3 hrs (aOR 2.0, 95% CI 1.4-2.9; p <0.001) after adjustment for age, NIHSS, IV tPA and mTICI ≥2b (Table 2). No differences were found in mortality and sICH. Treatment in the golden hours had the highest impact on excellent outcome rates (mRS 0-1) (Fig 1).

Conclusion: Early thrombectomy of LVO strokes, within the first three hours provides the highest impact compared with later time windows. Streamlining processes to deliver rapid intervention within 3 hours would improve clinical outcomes.

Abstract TP20: Uncertainties of Endovascular Therapy Outside the AHA Guidelines

Background: The efficacy of endovascular therapy (EVT) in randomized clinical trials (RCTs) for acute strokes due to large vessel occlusion (LVO) led to AHA guidelines recommending EVT as standard of care for selected patients. However, many conditions were under-represented in the RCTs: ASPECTS <6, age ≥80 yo, NIHSS <6, onset to treatment >6 hrs and M2/ distal/ posterior circulation occlusions.

Objective: We evaluated EVT outcomes in these populations compared to counterparts represented in the RCTs.

Methods: A large multicenter international prospective cohort study of LVO patients treated with stent retriever thrombectomy (TREVO Registry) between 11/2013 and 4/2016 was analyzed. 90 day mRS was the primary outcome (0-2 good outcome). Multivariate logistic regression modeling was employed to evaluate EVT impact in the different groups.

Results: Of 1000 patients, 81 had NIHSS <6 and 81.5% of those achieved a good outcome (aOR 3.6, 95% CI 1.9-6.8; p< 0.001 compared with NIHSS ≥6) (Table 1). Over 80 yo, however, had low odds of independence (aOR 0.3, 95% CI 0.2-0.5; p <0.001 compared with <80 yo). Among 212 patients treated >6 hrs, 51% had a good outcome (aOR 0.78, 95% CI 0.55-1.1; p =0.17) compared to ≤6 hrs. Nearly half of patients with ASPECTS <6 (3-5) had a good outcome. Fig 1 illustrates mRS distributions stratified by the different subgroups. There were low rates of sICH for treated patients with NIHSS<6, age≥80, ASPECTS <6 or treatment >6 hrs. Fig 2 demonstrates the likelihood of good outcome by clot location. M2 and distal occlusions had the highest good outcome probabilities while proximal ICAs had the lowest (48.1%). More than half of vertebrobasilar patients achieved independence (54.8%).

Conclusion: While effectiveness cannot be determined in the absence of medically treated controls, our analyses of real world data show several groups outside AHA guidelines may benefit from EVT. In particular, further study is needed to examine EVT benefits for mild stroke and M2 occlusions.

Abstract WP4: Transfer Patients and Patients Presenting Directly to Endovascular Capable Centers Achieve Similar Good Outcome Rates with Endovascular Therapy

Background: While endovascular therapy (EVT) is effective for large vessel occlusions (LVO), most patients present to hospitals without EVT capability and are transferred for intervention, delaying treatment.

Objective: We evaluated outcomes in LVO patients treated with thrombectomy who were transferred compared to those presenting directly to EVT facilities.

Methods: In a large multicenter international prospective cohort study of LVO patients treated with stent retriever thrombectomy (TREVO Registry), patients were stratified by initial presentation into transferred (TNS) vs direct (DIR). 90 day mRS was the primary outcome (0-1 excellent, 0-2 good outcomes); sICH and reperfusion by mTICI were secondary outcomes. Outcomes were compared in the 2 groups (0-8 hrs onset to groin puncture (GP) then in time matched 3-8 hrs subgroups for validation). Logistic regression identified independent predictors of good outcome in TNS patients.

Results: We identified 540 patients (230 TNS; 310 DIR) (Fig 1). TNS patients were younger and had longer onset to GP times (4.6 vs 3.1 hrs; p <0.001) (Table 1). DIR achieved higher excellent outcomes (50.4 vs 38.7%; p <0.001) (Table 2). There were no significant differences in good clinical outcomes (61 DIR vs 57.4% TNS, OR 0.90, 95% CI 0.63-1.27; p =0.4) (Fig 2) and no difference in the time matched 3-8 hrs subgroups (59.2% DIR vs 56.3% TNS, p =0.6). Fig 3 plots good outcome probabilities over time, showing similar confidence interval bands. Younger age (OR 0.95), lower NIHSS (OR 0.90), glucose level < 170 mg/dL (OR 2.4), distal clot location (M2) (OR 1.7), excellent reperfusion (mTICI≥2b) (OR 2) and time to GP <5 hrs (OR 1.6) were independent predictors of good outcome in TNS patients.

Conclusion: While excellent outcomes were higher in directly-presenting patients, EVT-treated transfers may achieve similar good outcomes. The association between earlier EVT after transfer and better outcomes emphasizes the need to streamline the transfer process.