Remote Longitudinal Inpatient Acute Stroke Care Via Telestroke

OBJECTIVES

While telestroke 'hub-and-spoke' systems are a well-established model for improving acute stroke care at spoke facilities, utility beyond the hyperacute phase is unknown. In patients receiving intravenous thrombolysis via telemedicine, care at spoke facilities has been shown to be associated with longer length of stay and worse outcomes. We sought to explore the impact of ongoing stroke care by a vascular neurologist via telemedicine compared to care provided by local neurologists.

METHODS

A network spoke facility protocol was revised to pilot telestroke consultation with a hub vascular neurologist for all patients presenting to the emergency department with ischemic stroke or transient ischemic attack regardless of time since onset or severity. Subsequent telestroke rounds were performed for patients who received initial telestroke consultation. Key outcome measures were length of stay, 30-day readmission and mortality and 90-day mRS. Results during the pilot (post-cohort) were compared to the same hospital's previous outcomes (pre-cohort).

RESULTS

Of 257 enrolled patients, 67% were in the post-cohort. Forty percent (69) of the post-cohort received an initial telestroke consult. In spoke-retained patients followed by telestroke rounds (55), median length of stay decreased by 0.8 days (P = 0.01). Readmission and mortality rates did not differ significantly between groups (19.5 vs. 9.1%, P = 0.14 and 3.9 vs. 3.6%, P = 1, respectively). The favorable functional outcome rate was similar between groups (47.3% vs 65.9%, P = 0.50).

CONCLUSIONS

Longitudinal stroke care via telestroke may be economically viable through length of stay reduction. Randomized prospective studies are needed to confirm our findings and further investigate this model's potential benefits.

Predictors and outcomes of ischemic stroke in reversible cerebral vasoconstriction syndrome

INTRODUCTION

The clinical factors predisposing to ischemic stroke in reversible cerebral vasoconstriction syndrome (RCVS) are unclear. In this observational cross-sectional study, we aimed to evaluate the risk factors and clinical outcomes associated with the development of ischemic stroke in patients with RCVS.

METHODS

We utilized the Nationwide Readmissions Database 2016-2017 to identify all hospitalizations with RCVS, with or without acute ischemic stroke. Independent predictors of and clinical outcomes associated with ischemic stroke were analyzed using logistic regression.

RESULTS

Among 1065 hospitalizations for RCVS (mean ± SD age 49.0 ± 16.7 years, female 69.7%), 267 (25.1%) had ischemic stroke. Patients with ischemic stroke were more likely to have hypertension (OR 2.33, 95% CI 1.51-3.60), diabetes (OR 1.81, 95% CI 1.11-2.98), and tobacco use (OR 1.64, 95% CI 1.16-2.33) and were less likely to have a history of migraine (OR 0.56, 95% CI 0.35-0.90). Ischemic stroke was associated with higher odds of cerebral edema (OR 3.15, 95% CI 1.31-7.57) and respiratory failure (OR 2.39, 95% CI 1.28-4.44). Patients with ischemic stroke also had longer hospital stay by a mean duration of 6.7 days, P < 0.001, higher hospital charges by a mean of $72,961, P < 0.001, and a higher likelihood of not being discharged to home (OR 3.57, 95% CI 2.39-5.33). They had higher in-hospital mortality rate; however, the difference was not statistically significant.

CONCLUSION

Ischemic stroke affects nearly 25% of patients with RCVS and is associated with adverse clinical outcomes. RCVS patients with cerebrovascular risk factors might have a higher predisposition for developing ischemic lesions during the disease process.

Predictors and outcomes of hemorrhagic stroke in reversible cerebral vasoconstriction syndrome

BACKGROUND

Intracranial hemorrhage (ICH) is the most common neurologic complication of reversible cerebral vasoconstriction syndrome (RCVS). In this study, we compared hemorrhagic and non-hemorrhagic RCVS with an aim to evaluate the risk factors and short-term clinical outcomes of hemorrhagic lesions.

METHODS

We used the Nationwide Readmissions Database 2016-2017 to identify all hospitalizations due to RCVS. Predictors and clinical outcomes of ICH were analyzed using logistic regression analysis.

RESULTS

Among the total 1834 hospitalizations for RCVS during the study period (mean ± SD age:48.4 ± 15.6 years, female:75.8%), 768 (41.9%) had occurrence of ICH. Patients with ICH were more likely to be female (OR:2.72, 95% CI:1.86-3.97), have a history of hypertension (OR:1.63, 95% CI:1.20-2.22) and cocaine use (OR:3.11, 95% CI:1.49-6.51), and were less likely to have a history of diabetes (OR:0.52, 95% CI:0.32-0.84) and heart failure (OR:0.34, 95% CI:0.14-0.84). Hemorrhagic RCVS was associated with higher odds of cerebral edema (OR:10.71, 95% CI:5.75-19.97), new onset seizure (OR:2.24, 95% CI:1.08-4.61), respiratory failure (OR:2.40, 95% CI:1.37-4.22) and gastrostomy tube placement (OR:3.20, 95% CI:1.07-9.58). Patients with hemorrhagic lesions also had longer length of hospital stay (mean difference 5.5 days), higher hospital charges (mean difference $105,547), and a lower likelihood of discharge to home (OR:0.61, 95% CI:0.43-0.86). There was, however, no significant difference in the in-hospital mortality.

CONCLUSIONS

ICH affects nearly 42% of patients with RCVS and is associated with increased rate of other neurologic complications and adverse discharge disposition, thus putting into question the prevailing conception that RCVS is generally a benign disorder with a self-limiting clinical course.

Genome-wide transcriptomic analysis of microglia reveals impaired responses in aged mice after cerebral ischemia

Senescence-associated alterations in microglia may have profound impact on cerebral homeostasis and stroke outcomes. However, the lack of a transcriptome-wide comparison between young and aged microglia in the context of ischemia limits our understanding of aging-related mechanisms. Herein, we performed RNA sequencing analysis of microglia purified from cerebral hemispheres of young adult (10-week-old) and aged (18-month-old) mice five days after distal middle cerebral artery occlusion or after sham operation. Considerable transcriptional differences were observed between young and aged microglia in healthy brains, indicating heightened chronic inflammation in aged microglia. Following stroke, the overall transcriptional activation was more robust (>13-fold in the number of genes upregulated) in young microglia than in aged microglia. Gene clusters with functional implications in immune inflammatory responses, immune cell chemotaxis, tissue remodeling, and cell-cell interactions were markedly activated in microglia of young but not aged stroke mice. Consistent with the genomic profiling predictions, post-stroke cerebral infiltration of peripheral immune cells was markedly decreased in aged mice compared to young mice. Moreover, post-ischemic aged microglia demonstrated reduced interaction with neighboring neurons and diminished polarity toward the infarct lesion. These alterations in microglial gene response and behavior may contribute to aging-driven vulnerability and poorer recovery after ischemic stroke.

Neurothrombectomy for Acute Ischemic Stroke Across Clinical Trial Design and Technique: A Single Center Pooled Analysis

Introduction: The practice of endovascular therapy has evolved dramatically over the last 10 years with randomized clinical trials investigating the benefit of thrombectomy in select patient populations based on time of presentation, imaging criteria, and procedural technique. We sought to understand the benefit of thrombectomy in patients treated within the context of a clinical trial at a single academic center.

Methods: Patient-level data recorded in case forms and core-lab adjudicated data were analyzed from patients enrolled in RCTs investigating the benefit of endovascular thrombectomy over medical management (IMSIII, MR RESCUE, ESCAPE, SWIFT PRIME, and DAWN) between 2007 and 2017 at a single academic referral center.

Results: A total of 134 patients (intervention group, n = 81; medical group, n = 53) were identified across five clinical trials (IMSIII, n = 46; MR RESCUE, n = 4; ESCAPE, n = 24; SWIFT PRIME, n = 14; DAWN, n = 46). There were no significant differences between the treatment arm and control arm in terms of age, gender, baseline NIHSS, ASPECTS, and site of occlusion. Rates of good outcome were superior in the intervention group with early neurological recovery (NIHSS of 0–1 or increase NIHSS of 8 points at 24 h) at a higher rate of 49% vs. 17% (p = <0.001) and higher rates of functional independence (90 day mRS 0–2 of 53% vs. 26%, p = 0.002). In multivariate logistic regression analysis, lower NIHSS and younger age were predictors of good outcome. There were comparable rates of good outcome irrespective of clinical trial, imaging selection criteria (CTP vs. MRI), early vs. late time window (0–6 h vs. 6–24 h) and procedural technique (Merci vs. Solitaire/Trevo device). There were no differences in rates of sICH, PH-2 or mortality in the intervention group vs. medical group.

Conclusions: At a large academic center, the benefit of endovascular therapy over medical therapy is observed irrespective of clinical trial design, patient selection or procedural technique.

Learnings from a decade experience of a community-based HIV and STI testing and counseling center in Lisbon – Portugal

Background

In the context of an increased number of men who have sex with men (MSM) being diagnosed with HIV infection in many European countries, it became a matter of maximum priority to consider new strategies to monitor and tackle the epidemic. In this scenario, CheckpointLX and a cohort study were projected as a sexual health and research center oriented towards MSM in Portugal.

Methods

In 2011 CheckpointLX was launched in Lisbon as a community-based center for anonymous and free rapid HIV and other sexually transmitted diseases (STI) testing with a strong component of counseling for sexual health, specially targeted at MSM. In the case of a reactive test, a medical appointment is proposed and scheduled. The Lisbon Cohort of MSM is an ongoing observational prospective study conducted at CheckpointLX. Collected data include sexual behaviors, preventive strategies, and history of STI.

Results

Until July 2019, 7,351 HIV-negative MSM chose to participate in the Lisbon Cohort of MSM. 3,523 had at least one follow-up visit. The median age was 29 (IQR 25 - 37), and 27% were born in a foreign country, including 15% born in Africa and South America. HIV incidence increased up until 2015, reaching 5 reactive tests per 100 tested annually. There has been a sustained decrease in HIV observed since 2015. The use of HIV prevention tools was provided: 31% used condoms consistently, 3% reported PrEP, and 4% PEP.

Conclusions

A decade since the beginning of this experience shows positive results, such as increased access and testing. We promoted a stigma-free service that facilitated MSM's and other key population's access to sexual health care. We contribute unique data for assisting in the monitoring of the Dublin Declaration in Portugal.

Delayed functional independence after thrombectomy: temporal characteristics and predictors

Background

Variability in early neurological improvement after endovascular thrombectomy (EVT) for large vessel occlusion (LVO) stroke is well documented. Understanding the temporal progression of functional independence after EVT, especially delayed functional independence in patients who do not experience early improvement, is essential for prognostication and rehabilitation.

Objective

To determine the incidence of early and delayed functional independence and identify associated predictors after EVT.

Methods

A retrospective analysis of prospectively collected data on patients undergoing EVT in the setting of anterior circulation LVO was performed. Demographic, clinical, radiological, treatment, and procedural information were analyzed. Incidence and predictors of early functional independence (EFI, modified Rankin Scale (mRS) score 0–2 at discharge) and delayed functional independence (DFI, mRS score 0–2 at 90 days in non-EFI patients) were analyzed.

Results

Three hundred and fifty-five patients met the study criteria. 55% were women and mean age was 71±15. Mean National Institutes of Health Stroke Scale (NIHSS) score was 17±6 and median Alberta Stroke Program Early CT Score was 9 (8-10). EFI was observed in 21% (73) of patients. Among non-EFI patients (282), DFI was observed in 30% (85) of patients. Shorter time to treatment (p=0.03), lower 24 hours NIHSS score (p<0.001), and smaller follow-up infarct volume (p=0.003) were independent predictors of EFI. Younger age (p=0.011), lower 24 hours NIHSS score (p=0.001), and absence of parenchymal hemorrhage (PH2; p=0.039) were independent predictors of DFI.

Conclusion

Approximately one-fifth of patients experience EFI and one-third of non-early improvers experience DFI. Younger age, lower 24 hours NIHSS score, and absence of parenchymal hemorrhage were independent predictors of DFI among non-early improvers. Further studies are required to improve our understanding of DFI.

Interaction between time, ASPECTS, and clinical mismatch

Background

Imaging-based patient selection for neurothrombectomy is reliant on the identification of irreversibly damaged brain tissue (core) and salvageable tissue (penumbra). The DAWN trial used the clinical-core mismatch (CCM) paradigm (clinical deficit out of proportion to infarct volume). We aim to determine the prevalence of CCM in large vessel occlusion (LVO) strokes and study the impact of time and the Alberta Stroke Program Early CT Score (ASPECTS) on the likelihood of mismatch.

Methods

We performed a retrospective observational analysis of internal carotid artery/middle cerebral artery M1 occlusions with available advanced imaging (relative cerebral blood flow/MRI). We used automated software for infarct volume analysis and ASPECTS determination. The prevalence of CCM and the impact of time and ASPECTS were analyzed.

Result

One hundred and eighty-five LVO strokes were included. Mean age was 71±15 years and median National Institutes of Health Stroke Scale score was 17 (range 12–21). Mean ischemic core volume was 50±69 mL. Within 0–24 hours, CCM was present in 53% and ranged from 63% in 0–3 hours to 25% at 21–24 hours (p=0.03). Prevalence of mismatch reduced 1.6% for every 1 hour increase in time to imaging. CCM prevalence by ASPECTS groups was: ASPECTS 9–10: 77%, ASPECTS 6–8: 65%, ASPECTS 0–5: 13% (p<0.01), with a 6.4% decrement for every 1 point decrease in ASPECTS. The prevalence of mismatch did not diminish over time among ASPECTS groups and higher ASPECTS was an independent predictor of CCM (OR 1.4 (95% CI 1.1 to 1.7), p<0.001).

Conclusions

CCM is present in 57% and 50% of LVO strokes in the 0–6 and 6–24 hour window, respectively. The prevalence of mismatch declines with increasing time (1.6%/hour) and decreasing ASPECTS (6.4%/point). Among ASPECTS groups the prevalence of mismatch does not decline over time. These data support the use of an ASPECTS-based paradigm for late window patient selection.

RNA sequencing reveals novel macrophage transcriptome favoring neurovascular plasticity after ischemic stroke

Blood monocytes/macrophages infiltrate the brain after ischemic stroke and critically influence brain injury and regeneration. We investigated stroke-induced transcriptomic changes of monocytes/macrophages by RNA sequencing profiling, using a mouse model of permanent focal cerebral ischemia. Compared to non-ischemic conditions, brain ischemia induced only moderate genomic changes in blood monocytes, but triggered robust genomic reprogramming in monocytes/macrophages invading the brain. Surprisingly, functional enrichment analysis of the transcriptome of brain macrophages revealed significant overrepresentation of biological processes linked to neurovascular remodeling, such as angiogenesis and axonal regeneration, as early as five days after stroke, suggesting a previously underappreciated role for macrophages in initiating post-stroke brain repair. Upstream Regulator analysis predicted peroxisome proliferator-activated receptor gamma (PPARγ) as a master regulator driving the transcriptional reprogramming in post-stroke brain macrophages. Importantly, myeloid cell-specific PPARγ knockout (mKO) mice demonstrated lower post-stroke angiogenesis and neurogenesis than wild-type mice, which correlated significantly with the exacerbation of post-stroke neurological deficits in mKO mice. Collectively, our findings reveal a novel repair-enhancing transcriptome in brain macrophages during post-stroke neurovascular remodeling. As a master switch controlling genomic reprogramming, PPARγ is a rational therapeutic target for promoting and maintaining beneficial macrophage functions, facilitating neurorestoration, and improving long-term functional recovery after ischemic stroke.

Transforming Growth Factor Beta-Activated Kinase 1-Dependent Microglial and Macrophage Responses Aggravate Long-Term Outcomes After Ischemic Stroke

Background and Purpose- Microglia/macrophages (Mi/MΦ) can profoundly influence stroke outcomes by acquiring functionally dominant phenotypes (proinflammatory or anti-inflammatory; deleterious or salutary). Identification of the molecular mechanisms that dictate the functional status of Mi/MΦ after brain ischemia/reperfusion may reveal novel therapeutic targets for stroke. We hypothesized that activation of TAK1 (transforming growth factor beta-activated kinase 1), a key MAP3K upstream of multiple inflammation-regulating pathways, drives Mi/MΦ toward a proinflammatory phenotype and potentiates ischemia/reperfusion brain injury. Methods- Young adult mice were subjected to 1 hour of middle cerebral artery occlusion (MCAO) followed by reperfusion. TAK1 was targeted by tamoxifen-induced Mi/MΦ-specific knockout or administration of a selective inhibitor 5Z-7-Oxozeaenol after MCAO. Neurobehavioral deficits and long-term gray matter and white matter injury were assessed up to 35 days after MCAO. Mi/MΦ functional status and brain inflammatory profiles were assessed 3 days after MCAO by RNA-seq, flow cytometry, and immunohistochemistry. Results- TAK1 Mi/MΦ-specific knockout markedly ameliorated neurological deficits in the rotarod and cylinder tests for at least 35 days after MCAO. Mechanistically, RNA-seq of purified brain Mi/MΦ demonstrated that proinflammatory genes and their predicted biological functions were downregulated or inhibited in microglia and macrophages from TAK1 Mi/MΦ-specific knockout mice versus WT mice 3 days after MCAO. Consistent with the anti-inflammatory phenotype of Mi/MΦ-specific knockout, oxozeaenol treatment mitigated neuroinflammation 3 days after MCAO, manifested by less Iba1⁺/CD16⁺ proinflammatory Mi/MΦ and suppressed brain invasion of various peripheral immune cells. Oxozeaenol treatment beginning 2 hours after MCAO improved long-term sensorimotor and cognitive functions in the foot fault, rotarod, and water maze tests. Furthermore, Oxozeaenol promoted both gray matter and white matter integrity 35 days after MCAO. Conclusions- TAK1 promotes ischemia/reperfusion-induced inflammation, brain injury, and maladaptive behavior by enhancing proinflammatory and deleterious Mi/MΦ responses. Therefore, TAK1 inhibition is a promising therapy to improve long-term stroke outcomes.

Abstract WP163: Clinical Characteristics of Fast and Slow Progressors of Infarct Growth Due to Anterior Circulation Large Vessel Occlusion

Background and Purpose: Inter-individual variability of fast to slow progression of early infarct growth in anterior circulation large vessel occlusion (ACLVO) stroke has been previously well quantified. However, the underlying pathophysiology of these clinical phenotypes remains poorly understood. We aimed to determine clinical and radiographic variables associated with fast or slow progressor phenotypes of ACLVO stroke.

Methods: Single-center retrospective study of all patients with intracranial ICA or MCA occlusion, with or without tandem cervical ICA occlusion, who underwent baseline advanced imaging including CTP or MRI within 24 hours of stroke onset. Fast progressors (ischemic core > 70 ml, < 6 hours of stroke onset) and slow progressors (ischemic core ≤ 30 ml, > 6 to 24 hours of stroke onset) were identified. Demographics, co-morbidities, admission NIHSS and ACLVO type were tested in univariate and multivariate analysis for association with fast or slow progressor status.

Results: A total of 185 patients were included with mean age 71 ± 15 and NIHSS 17 ± 7; 60% were female. Patients had occlusion of the MCA in 72% or the intracranial ICA in 28% of cases. Of these, 20% had a tandem cervical ICA occlusion. In the early epoch, there were no significant differences in age, sex, NIHSS, co-morbidities or ACLVO type between fast progressors (n=19) versus controls (n=56). In the delayed epoch, the mean NIHSS was 14±6 in slow progressors (n=61) versus 19±7 in controls (n=49). Slow progressors had MCA occlusion in 80% versus 63% (p < 0.05) and tandem occlusion in 10% versus 35% of controls (p < 0.01). In multivariate logistic regression modeling, age (OR 1.04, 95% CI 1.01-1.07) and NIHSS (OR 0.87, 95% CI 0.81-0.93) but not ACLVO types were independently associated with slow progressor status.

Conclusions: Although greater frequency of MCA occlusion and absence of tandem cervical ICA occlusion were prevalent amongst slow progressors, only age and NIHSS were independent predictors. Future studies are needed to better characterize the underlying clinical substrates for fast versus slow progression of ACLVO stroke.

Abstract WP21: “Stunned Brain”– Early versus Delayed Clinical Recovery After Neurothrombectomy

Introduction: Heterogeneity in early neurological improvement after neurothrombectomy for large vessel occlusion (LVO) stroke is well documented. Delayed clinical recovery is observed in a subset of patients who do not experience early improvement. Understanding the temporality of clinical recovery after thrombectomy is essential in guiding prognostication and targeting rehabilitation. In this study, we aim to describe the characteristics and incidence of early and delayed clinical recovery and identify their predictors after LVO stroke thrombectomy.

Methods: A retrospective analysis of prospectively-collected data on patients undergoing anterior circulation LVO stroke thrombectomy. Demographic characteristics, clinical and radiological data, treatment and procedural information were extracted and analyzed. Characteristics and predictors of early clinical recovery (ECR-1-NIHSS <6 at 24 hours and ECR-2-mRS 0-2 at discharge) and delayed clinical recovery (DCR-1 and 2- mRS 0-2 at 90 days) were analyzed. Statistical analyses were performed on SPSS 23 (IBM, Armonk, NY).

Results: Three hundred and fifty-five patients met study criteria. 55% (195) were females and mean age was 71±15 years. Mean NIHSS score and median ASPECTS were 17±6 and 9 (8-10), respectively. ECR-1 and ECR-2 were observed in 31% (115) and 21% (73) patients, respectively. Among non-ECR patients, delayed recovery was observed in 27-30% of patients. Lower NIHSS [OR-0.83 (0.75-0.91), p=<0.01] and higher ASPECTS [OR-2.14, (1.29-3.54), p=0.003] scores were independent predictors of ECR-1 and younger age [OR-0.96 (0.94-0.99), p=0.01] and absence on parenchymal hemorrhage (PH) [OR-3.1 (1.3-7.1), p=0.007] were independent predictors of DCR-1. Among non-early improvers, patients <80 years and without PH have a 40% chance of DCR compared to no patients over 80 years with parenchymal hemorrhage experiencing DCR.

Conclusion: About one-third of patients experience early clinical recovery (ECR-1-31%) and approximately one-third (DCR-1-30%) of non-early improvers experience delayed clinical recovery. Lower NIHSS score and higher ASPECTS predict ECR while younger age and absence of parenchymal hemorrhage predict DCR.

Abstract 110: RNA Sequencing Reveals Novel Macrophage Transcriptome Favoring Neurovascular Plasticity After Ischemic Stroke

Introduction: Blood monocytes/macrophages (MΦ) infiltrate the brain in massive numbers after ischemic stroke, but their functional roles in the post-stroke brain remain elusive.

Methods: We sorted CD11b + CD45 high monocytes/MΦ from mouse blood and brain 5d after distal MCAO (dMCAO) and investigated their transcriptomic profiles by RNA-seq (n=3/group).

Results: Robust genomic changes occurred in MΦ invading the post-dMCAO brain compared to their counterparts in the blood (3196 differentially expressed genes with >2 fold changes; FDR<0.05). In addition to their canonical role in immune responses, brain MΦ expressed unique transcriptomic programs which may favor post-stroke neurovascular repair. Functional enrichment analysis of brain MΦ transcriptome revealed significant overrepresentation (p<0.01) of 110 biological processes linked to neurovascular remodeling and plasticity (e.g., angiogenesis and axonal regeneration), suggesting a previously underappreciated role for MΦ in post-stroke brain repair. Upstream Regulator analysis predicted PPARγ as a master regulator (z-score=2.64, p<10 -15 ) that drives the transcriptional reprogramming in post-stroke brain MΦ and dictates their functional phenotype. Accordingly, tamoxifen-induced, myeloid cell-specific PPARγ knockout mice demonstrated less post-stroke angiogenesis (BrdU+CD31 staining) and neurogenesis (BrdU+NeuN) than WT mice (n=9/group, p<0.01), which correlated significantly with the exacerbation of neurological deficits in these mice (n=9/group, p<0.01 vs WT in foot fault and adhesive removal tests) at 35d after dMCAO.

Conclusions: Our study reveals a novel repair-enhancing transcriptome in brain MΦ during post-stroke neurovascular remodeling. As a master molecule controlling genomic reprogramming, PPARγ is a rational therapeutic target for promoting beneficial MΦ functions, and facilitating neurorestoration and long term functional recovery after ischemic stroke.

Abstract TP248: Reduced Door-in-Door-Out Time Increases the Likelihood of Endovascular Thrombectomy for Large Vessel Occlusion Patients

Introduction: Endovascular thrombectomy (EVT) is recommended for patients with large vessel occlusion (LVO) presenting within 24 hours of last seen well (LSW). Unfortunately, patients transferred from spoke hospitals to receive EVT have poorer outcomes compared to those presenting directly to the hub, underscoring the importance of rapid transfer timing - door-in-door-out (DIDO).

Methods: Data were analyzed from consecutive acute ischemic stroke patients with proximal large vessel occlusions (LVO) transferred to our comprehensive stroke center for EVT. The following variable were studied: DIDO, baseline NIHSS/mRS, presentation CT ASPECTs, site of LVO, treatment, and clinical outcome.

Results: Ninety patients with internal carotid or middle cerebral artery (M1) occlusion at the spoke hospital were included in the study. At the hub hospital, 75% (68) underwent emergent cerebral angiography (DSA) with intent to perform EVT. Reasons for not undergoing angiography at hub hospital included large stroke burden (59%) and improvement in NIHSS score (41%). Overall, DIDO time was 184 (130-285) minutes. Mean DIDO time was significantly lower for patients who underwent DSA at hub hospital compared to patients who did not (207 versus 272 minutes, p=0.031). 92% (12) of patients with DIDO <=120 minutes (n=13) underwent EVT compared to 73% (56) of patients with DIDO >120 minutes (n=77). Every 30-minute delay after 120 minutes lead to a 6% reduction in the likelihood of EVT. Lower DIDO time [OR-0.92 (0.9-0.96), p=0.04] and higher ASPECTS score [OR-1.4 (1.1-1.9), p=0.013] at spoke hospital are predictors of EVT at hub hospital.

Conclusion: Reduced DIDO times are associated with higher likelihood of receiving EVT. DIDO should be treated on par as in-hospital time metrics and methods should be in place to optimize transfer times.

Abstract TP2: Impact of Neglect on Outcomes After Right Hemisphere Stroke Thrombectomy

Introduction: Right Hemisphere Strokes (RHS) are characterized by severe motor and sensory deficits and signs of neglect including extinction and inattention. National Institutes of Health Stroke Scale (NIHSS) score provides an objective measurement of presence or absence of neglect. Data regarding the impact of neglect on outcomes after RHS thrombectomy are lacking. We hypothesize that the presence of neglect in RHS is associated with worse outcomes after thrombectomy in RHS.

Methods: Retrospective analysis of prospectively collected database of right sided anterior circulation large vessel occlusion [internal carotid and/or middle cerebral artery M1] strokes at a comprehensive stroke center. Patients with successful recanalization (TICI≥ 2B) and complete follow-up data were included in the study. Two group of RHS were identified- with and without neglect by itemized NIHSS. Baseline characteristics and outcomes were compared.

Results: A total of 172 patients were included in the study. Median NIHSS score was 15 (11-18) and median ASPECTS was 9 (8-10). Signs of neglect were observed in 63% (108) of patients. In multivariate analyses, younger age [0.9 (0.8-0.95) p=<0.01] and higher ASPECTS [1.8 (1.1-3.1) p=0.015] were independent predictors of mRS 0-2 at 90 days. Absence of neglect [0.39 (0.13-1.1) p=0.07] may predict good outcome. Independent predictors of mortality on multivariate analyses included older age [1.1 (1.03-1.15) p =0.001], presence of atrial fibrillation [0.3 (0.1-1) p=0.05] and diabetes mellitus [0.16 (0.05-0.53) p=0.003]. Presence of neglect [2.5 (0.9-6.6) p=0.06] and lower ASPECTS [0.7 (0.4-1) p=0.06] may predict mortality.

Conclusion: Signs of neglect were observed in approximately 63% of right hemisphere LVO strokes. Presence of neglect may predict poor functional outcome and mortality at 90 days after thrombectomy for right hemisphere strokes. Further studies are required to evaluate the impact of thrombectomy on recovery of neglect.

Abstract 32: Intravenous Tpa Delays Door-to-puncture Time in Acute Ischemic Stroke With Large Vessel Occlusion

Background: The current 2018 AHA/ASA Guidelines for early stroke management recommend use of IV tPA in all eligible acute ischemic stroke patients within 4.5 hours of onset while being considered for mechanical thrombectomy (MT). Whether or not tPA administration is beneficial prior to thrombectomy is still an ongoing debate. Potential delay of MT initiation due to tPA start is a major concern but has not been well-delineated in empirical studies.

Methods: In a prospective large volume comprehensive stroke center registry, we analyzed all patients with acute ischemic stroke due to large vessel occlusion (AIS-LVO) treated with thrombectomy between 2012-2017, who arrived directly from field to ED within 4.5h of last known well. Patients without contraindication to IV-tPA are given bolus dose in the scanner suite and the remainder of the 1h infusion en route to and in the angio-suite to prevent delay.

Results: Among 777 thrombectomy patients identified in the database, 237 arrived directly within 4.5 hours from onset, including 65.8% (156) not treated with IV-tPA and 34.2% (81) receiving IV-tPA, both well-matched in age and NIHSS. Overall, the door-to-needle (DTN) time was 40m (IQR31-56), surpassing the Target Stroke national targets (60m and 45m) active during the study period. However, median door-to-puncture (DTP) time was 22m longer in the IV-tPA group, 74 vs 52m (p<0.001). IV-tPA was not independently associated with better recanalization rate (TICI 2B-3 95.9% vs 92.9%) or functional independent outcome (modified Rankin score 0-2) at 90 days, 37.3% vs 39.4%.

Conclusion: IV-tPA administration in AIS-LVO was associated with delayed door-to-puncture times in a comprehensive stroke center with efficient DTN times surpassing advanced national targets, without change in recanalization rate or outcomes. Randomized trials are needed to determine the net positive, neutral, or negative effect of IV-tPA in this population.

Abstract TP77: Impact of Time and Aspects on Clinical Core Mismatch in Large Vessel Occlusion Strokes

Introduction: Patient selection for endovascular thrombectomy (EVT) for anterior circulation large vessel occlusion (LVO) strokes in the 6-24-hour time window is dependent on delineating clinical core mismatch (CCM) as defined by DAWN trial criteria. In contrast, patient selection in the early window (0-6 hours) can be performed using ASPECTS on CT head. We aim to determine the prevalence of DAWN-CCM in LVO strokes and the impact of time and ASPECTS.

Methods: Retrospective analysis of large vessel occlusion [internal carotid and middle cerebral artery-M1] strokes at a CSC. Consecutive patients who underwent CT perfusion or MRI within 120 minutes of CT head were included in the study (treated and untreated). Ischemic core volume was assessed using RAPID [IschemaView] and ASPECTS using automated ASPECTS [Brainomix]. CCM was defined using DAWN trial criteria [DAWN-CCM: NIHSS ≥10 and core <31 ml, NIHSS ≥20 and core <51 ml].

Results: A total of 116 patients were included. Mean age was 71 ±14 and 62% were females. Mean ischemic core volume and median ASPECTS were 46 ±65 ml and 8 (6-9), respectively. In patients with NIHSS score ≥10 (98), 57% had DAWN-CCM in the 0-24-hour window. Proportion of patients with DAWN-CCM in 6-24-hour window was 70% (6-12 hours), 50% (12-18 hours), and 50% (18-24 hours) [p=0.35]. Proportion of patients with DAWN-CCM by ASPECTS group was 88% (ASPECTS 9-10), 64% (ASPECTS 6-8) and 13% (ASPECTS 0-5) [p=<0.01] (Figure 1). Probability of DAWN-CCM declines by 7% for every 2 hours increase in TLKW to imaging, and by 13% for every 1-point decrease in ASPECTS.

Conclusion: Approximately 57% of LVO strokes have clinical core mismatch. LVO strokes with DAWN-CCM decline with increasing time and decreasing ASPECTS. ASPECTS alone may be sufficient to identify patients with DAWN-CCM in a resource limited setting and avoid time consuming advanced imaging.

A new species of spiny driftwood catfish Spinipterus (Siluriformes: Auchenipteridae) from the Amazon basin

An expedition to the middle Rio Purus basin uncovered a remarkable new species of the genus Spinipterus. The new species has a very distinct and conspicuous colour pattern resembling a jaguar and it is almost four times larger than Spinipterus acsi, a small specimen (32 mm L_S ) from Caño Santa Rita, a right bank tributary of Río Nanay in Peru and a second specimen was reported from Rio Juruá, Amazonas State, Brazil. Although the new species is more similar in size and colour pattern to Liosomadoras, it shares the synapomorphies for Spinipterus. The new species differs from the congener by the following characters: (a) colour pattern with large black rosette-like spots over a light yellow to brown background (v. brown background with small dark blotches over the body); (b) adult body size reaching 104.5 mm L_S (v. maximum known size 37.1 mm L_S ); (c) posterior process of cleithrum short, never reaching vertical through the dorsal-fin origin (v. posterior process long, surpassing vertical through the dorsal-fin origin); (d) seven soft pectoral-fin rays (v. six); (e) caudal fin truncated (v. caudal fin rounded).