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BackgroundEndovascular therapy (EVT) for stroke improves outcomes but is time sensitive.ObjectiveTo compare times to treatment and outcomes between patients taken to the closest primary stroke center (PSC) with those triaged in the field to a more distant comprehensive stroke center (CSC).MethodsDuring the study, a portion of our region allowed field triage of patients who met severity criteria to a more distant CSC than the closest PSC. The remaining patients were transported to the closest PSC. We compared times to treatment and clinical outcomes between those two groups. Additionally, we performed a matched-pairs analysis of patients from both groups on stroke severity and distance to CSC.ResultsOver 2 years, 232 patients met inclusion criteria and were closest from the field to a PSC; 144 were taken to the closest PSC and 88 to the more distant CSC. The median additional transport time to the CSC was 7 min. Times from scene departure to alteplase and arterial puncture were faster in the direct group (50 vs 62 min; 93 vs 152 min; pConclusionsIn a densely populated setting, for patients with stroke who are EVT candidates and closest to a PSC from the field, triage to a slightly more distant CSC is associated with faster time to EVT, no delay to alteplase, and less disability at 90 days.

Background and Purpose— Interfacility transfers for thrombectomy in stroke patients with emergent large vessel occlusion (ELVO) are associated with longer treatment times and worse outcomes. In this series, we examined the association between Primary Stroke Center (PSC) door-in to door-out (DIDO) times and outcomes for confirmed ELVO stroke transfers and factors that may modify the interaction. Methods— We retrospectively identified 160 patients transferred to a single Comprehensive Stroke Center (CSC) with anterior circulation ELVO between July 1, 2015 and May 30, 2017. We included patients with acute occlusions of the internal carotid artery or proximal middle cerebral artery (M1 or M2 segments), with a National Institutes of Health Stroke Scale score of ≥6. Workflow metrics included time from onset to recanalization, PSC DIDO, interfacility transfer time, CSC arrival to arterial puncture, and arterial puncture to recanalization. Primary outcome measure was National Institutes of Health Stroke Scale at discharge and modified Rankin Scale (mRS) score at 90 days. Results— The median (Q1–Q3) age and National Institutes of Health Stroke Scale of the 130 ELVO transfers analyzed was 75 (64–84) and 17 (11–22). Intravenous alteplase was administered to 64% of patients. Regarding specific workflow metrics, median (Q1–Q3) times (in minutes) were 241 (199–332) for onset to recanalization, 85 (68–111) for PSC DIDO, 26 (17–32) for interfacility transport, 21 (16–39) for CSC door to arterial puncture, and 24 (15–35) for puncture to recanalization. Median discharge National Institutes of Health Stroke Scale score was 5 (2–16), and 46 (35%) patients had a favorable outcome at 90 days. Complete reperfusion (modified Thrombolysis in Cerebral Ischemia 2c/3) modified the deleterious association of DIDO on outcome. Conclusions— For patients diagnosed with ELVO at a PSC who are being transferred to a CSC for thrombectomy, longer DIDO times may have a deleterious effect on outcomes and may represent the single biggest modifiable factor in onset to recanalization time. PSCs should make efforts to decrease DIDO and routine use of DIDO as a performance measure is encouraged.

BackgroundIt is largely unknown whether functional outcomes after mechanical thrombectomy for large vessel occlusion (LVO) ischemic strokes differ by sex in non-clinical trial populations. We investigated sex differences in 90-day outcomes among ischemic stroke patients receiving mechanical thrombectomy.MethodsThis was a prospective cohort of adults treated with mechanical thrombectomy for LVO at a single academic comprehensive stroke center from July 2015 to April 2017. Data on independence (mRS ≤2) at hospital discharge and 90 days were collected prospectively. Multiple logistic regression was used to determine the association between sex and 90-day independence, first adjusting for demographics, pre-stroke mRS, and NIHSS, then by co-morbidities and time to thrombectomy, and finally by vessel recanalization and use of intravenous thrombolysis.ResultsWe included 279 patients, 52% of whom were female. Compared with males, females were older (median years (IQR) 81 (75–88) vs. 71.5 (60–81), PConclusionsIn patients treated with mechanical thrombectomy for LVOs at a large comprehensive stroke center, females were less likely to be independent at 90 days. Future research should investigate contributors to poor outcomes post-discharge in females with LVOs, along with potential interventions to improve outcomes.

Background Many factors may potentially complicate the stroke recovery process, including persistently impaired level of consciousness (LOC)—whether from residual stroke effects or from superimposed delirium. We aimed to determine the degree to which impaired LOC at hospital discharge is associated with outcomes after ischemic stroke. Methods We conducted a single-center retrospective cohort study using prospectively-collected data from 2015 to 2017, collecting total NIHSS-LOC score at discharge as well as subscores for responsiveness (LOC-R), orientation questions (LOC-Q), and command-following (LOC-C). We determined associations between LOC scores and 3-month outcome using logistic regression, with discharge location (skilled nursing facility [SNF] vs. inpatient rehabilitation) representing a pre-specified secondary outcome. Results We identified 1003 consecutive patients with ischemic stroke who survived to discharge, of whom 32% had any LOC score > 0. Total LOC score at discharge was associated with unfavorable 3-month outcome (OR 4.9 [95% CI 2.4–9.8] for LOC = 1; OR 8.0 [2.7–23.9] for LOC = 2–3; OR 6.3 [2.1–18.5] for LOC = 4–5; all patients with LOC = 6–7 had poor outcomes), as were subscores for LOC-R (OR 5.3 [1.3–21.2] for LOC-R = 1; all patients with LOC-R = 2–3 had poor outcomes) and LOC-Q (OR 4.1 [2.1–8.3] for LOC-Q = 1; OR 4.9 [1.8–13.5] for LOC-Q = 2). Total LOC score (OR 2.6 [1.3–5.3] for LOC = 1; OR 3.1 [1.2–8.2] for LOC = 2–3) and LOC-Q (OR 3.3 [1.6–6.6] for LOC-Q = 1; OR 3.4 [1.3–9.0] for LOC-Q = 2) were also associated with discharge to SNF rather than to inpatient rehabilitation. Conclusions The presence of impaired consciousness or disorientation at discharge is associated with markedly worse outcomes after ischemic stroke. Further studies are necessary to determine the separate effects of residual stroke-related LOC changes and those caused by superimposed delirium.

Background and aims Baseline National Institutes of Health Stroke Scale (NIHSS) scores have frequently been used for prognostication after ischemic stroke. With the increasing utilization of acute stroke interventions, we aimed to determine whether baseline NIHSS scores are still able to reliably predict post-stroke functional outcome. Methods We retrospectively analyzed prospectively collected data from a high-volume tertiary-care center. We tested strength of association between NIHSS scores at baseline and 24 h with discharge NIHSS using Spearman correlation, and diagnostic accuracy of NIHSS scores in predicting favorable outcome at three months (defined as modified Rankin Scale 0–2) using receiver operating characteristic curve analysis with area under the curve. Results There were 1183 patients in our cohort, with median baseline NIHSS 8 (IQR 3–17), 24-h NIHSS 4 (IQR 1–11), and discharge NIHSS 2 (IQR 1–8). Correlation with discharge NIHSS was r = 0.60 for baseline NIHSS and r = 0.88 for 24-h NIHSS. Of all patients with follow-up data, 425/1037 (41%) had favorable functional outcome at three months. Receiver operating characteristic curve analysis for predicting favorable outcome showed area under the curve 0.698 (95% CI 0.664–0.732) for baseline NIHSS, 0.800 (95% CI 0.772–0.827) for 24-h NIHSS, and 0.819 (95% CI 0.793–0.845) for discharge NIHSS; 24 h and discharge NIHSS maintained robust predictive accuracy for patients receiving mechanical thrombectomy (AUC 0.846, 95% CI 0.798–0.895; AUC 0.873, 95% CI 0.832–0.914, respectively), while accuracy for baseline NIHSS decreased (AUC 0.635, 95% CI 0.566–0.704). Conclusion Baseline NIHSS scores are inferior to 24 h and discharge scores in predicting post-stroke functional outcomes, especially in patients receiving mechanical thrombectomy.

Background Occult paroxysmal atrial fibrillation (AF) is detected in 16%-30% of patients with embolic stroke of unknown source (ESUS). The identification of AF predictors on outpatient cardiac monitoring can help guide clinicians decide on a duration or method of cardiac monitoring after ESUS. Methods We included all patients with ESUS who underwent an inpatient diagnostic evaluation and outpatient cardiac monitoring between January 1, 2013, and December 31, 2016. Patients were divided into 2 groups based on detection of AF or atrial flutter during monitoring. We compared demographic data, clinical risk factors, and cardiac biomarkers between the 2 groups. Multivariable logistic regression was used to determine predictors of AF. Results We identified 296 consecutive patients during the study period; 38 (12.8%) patients had AF detected on outpatient cardiac monitoring. In a multivariable regression analysis, advanced age (ages 65-74: odds ratio [OR] 2.36, 95% confidence interval [CI] .85-6.52; ages 75 or older: OR 4.08, 95% CI 1.58-10.52) and moderate-to-severe left atrial enlargement (OR 4.66, 95% CI 1.79-12.12) were predictors of AF on outpatient monitoring. We developed the Brown ESUS-AF score: age (65-74 years: 1 point, 75 years or older: 2 points) and left atrial enlargement (moderate or severe: 2 points) with good prediction of AF (area under the curve .725) and was internally validated using bootstrapping. The percentage of patients with AF detected in each score category were as follows: 0: 4.2%; 1: 14.8%; 2: 20.8%; 3: 22.2%; 4: 55.6%. Conclusions The Brown ESUS-AF score predicts AF on prolonged outpatient monitoring after ESUS. More studies are needed to externally validate our findings.

BackgroundOlder patients undergoing thrombectomy for emergent large vessel occlusion have worse outcomes. However, complete or near-complete reperfusion (modified Thrombolysis in Cerebral Ischemia (mTICI) score of 2 c/3) is associated with improved outcomes compared with partial recanalisation (mTICI 2b).ObjectiveTo examine the relationship between outcomes and age separately for the mTICI 2c/3, 2b and 0-2a groups in patients undergoing thrombectomy for anterior circulation emergent large vessel occlusion.MethodsRetrospective review of 157 consecutive patients undergoing thrombectomy at a single centre with an occlusion of the internal carotid artery (ICA), M1 or proximal M2 segments of the middle cerebral artery (MCA). Angiograms were graded in a blinded fashion. Patients were divided into three groups: mTICI 0-2a, mTICI 2b, and mTICI 2c/3. Demographics and workflow parameters were compared. Outcomes at 90 days were compared as a function of age, using both the conventional modified Rankin scale (mRs) and utility weighted mRs (UWmRs).ResultsThere were 72, 61 and 24 patients in the mTICI 2c/3, 2b and 0-2a groups, respectively. Outcomes were significantly worse with increasing age for the mTICI 2b group, but not for the mTICI 0-2a and 2c/3 groups (P=0.0002). With increasing age, outcomes of the mTICI 2b group approached those of the mTICI 0-2a group. However, outcomes of the mTICI 2c/3 groups were similar for all ages. This association was present for both the original mRs and UWmRs.ConclusionIncreasing age was associated with worse outcomes for those with partial (mTICI 2b) recanalisation, not in patients with complete (mTICI 2c/3) recanalisation.

Background Large vessel disease stroke subtype carries the highest risk of early recurrent stroke. In this study we aim to look at the association between impaired perfusion and early stroke recurrence in patients with intracranial atherosclerotic disease or total cervical carotid occlusion. Methods This is a retrospective study from a comprehensive stroke center where we included consecutive patients 18 years or older with intracranial atherosclerotic disease or total cervical carotid occlusion admitted with a diagnosis of ischemic stroke within 24 h from symptom onset with National Institute Health Stroke Scale max > 6 s mismatch volume (penumbra volume–infarct volume) of 15 ml or more. The outcome was recurrent cerebrovascular events at 90 days defined as worsening or new neurological symptoms in the absence of a nonvascular cause attributable to the decline, or new infarct or infarct extension in the territory of the affected artery. We used Cox proportional hazards models to determine the association between impaired perfusion and recurrent cerebrovascular events. Results Sixty-two patients met our inclusion criteria; mean age 66.4 ± 13.1 years, 64.5% male (40/62) and 50.0% (31/62) with intracranial atherosclerotic disease. When compared to patients with favorable perfusion pattern, patients with unfavorable perfusion pattern were more likely to have recurrent cerebrovascular events (55.6% (10/18) versus 9.1% (4/44), p Conclusion Perfusion mismatch predicts recurrent cerebrovascular events in patients with ischemic stroke due to intracranial atherosclerotic disease or total cervical carotid occlusion. Studies are needed to determine the utility of revascularization strategies in this patient population.

Background Despite anticoagulation therapy, ischemic stroke risk in atrial fibrillation (AF) remains substantial. We hypothesize that left atrial enlargement (LAE) is more prevalent in AF patients admitted with ischemic stroke who are therapeutic, as opposed to nontherapeutic, on anticoagulation. Methods We included consecutive patients with AF admitted with ischemic stroke between April 1, 2015, and December 31, 2016. Patients were divided into two groups based on whether they were therapeutic (warfarin with an international normalized ratio ≥ 2.0 or non–vitamin K oral anticoagulant with uninterrupted use in the prior 2 weeks) versus nontherapeutic on anticoagulation. Univariable and multivariable models were used to estimate associations between therapeutic anticoagulation and clinical factors, including CHADS2 score and LAE (none/mild versus moderate/severe). Results We identified 225 patients during the study period; 52 (23.1%) were therapeutic on anticoagulation. Patients therapeutic on anticoagulation were more likely to have a larger left atrial diameter in millimeters (45.6 ± 9.2 versus 42.3 ± 8.6, P = .032) and a higher CHADS2 score (2.9 ± 1.1 versus 2.4 ± 1.1, P = .03). After adjusting for the CHADS2 score, patients who had a stroke despite therapeutic anticoagulation were more likely to have moderate to severe LAE (odds ratio, 2.05; 95% confidence interval, 1.01-4.16). Conclusion LAE is associated with anticoagulation failure in AF patients admitted with an ischemic stroke. This provides indirect evidence that LAE may portend failure of anticoagulation therapy in patients with AF; further studies are needed to delineate the significance of this association and improve stroke prevention strategies.

Background and Purpose— Elevated cardiac troponin is a marker of cardiac disease and has been recently shown to be associated with embolic stroke risk. We hypothesize that early elevated troponin levels in the acute stroke setting are more prevalent in patients with embolic stroke subtypes (cardioembolic and embolic stroke of unknown source) as opposed to noncardioembolic subtypes (large-vessel disease, small-vessel disease, and other). Methods— We abstracted data from our prospective ischemic stroke database and included all patients with ischemic stroke during an 18-month period. Per our laboratory, we defined positive troponin as ≥0.1 ng/mL and intermediate as ≥0.06 ng/mL and Results— We identified 1234 patients, of whom 1129 had admission troponin levels available; 10.0% (113/1129) of these had a positive troponin. In fully adjusted models, there was an association between troponin positivity and embolic stroke of unknown source subtype (adjusted odds ratio, 4.46; 95% confidence interval, 1.03–7.97; P =0.003) and cardioembolic stroke subtype (odds ratio, 5.00; 95% confidence interval, 1.83–13.63; P =0.002). Conclusions— We found that early positive troponin after ischemic stroke may be independently associated with a cardiac embolic source. Future studies are needed to confirm our findings using high-sensitivity troponin assays and to test optimal secondary prevention strategies in patients with embolic stroke of unknown source and positive troponin.

Background and Purpose— Within the thrombolysis in cerebral infarction (TICI) classification, TICI 2b has been historically considered successful recanalization. Recent studies have suggested that TICI 3 and a proposed TICI 2c should be separately reported from TICI 2b, in both the original (>66% reperfusion) and modified (>50% reperfusion) definitions, because of differences in clinical outcomes with greater reperfusion. The purpose of this study was to evaluate differences in early neurological improvement and independence at 90 days using the original TICI, modified TICI, and modified TICI with 2c scales. Methods— A retrospective review of 129 consecutive patients with middle cerebral artery, M1 segment or intracranial internal carotid artery occlusions. Patient angiograms were graded by 2 experienced readers by percentage recanalization. This was then categorized into original TICI, modified TICI (mTICI), and mTICI with TICI 2c (mTICI 2c) grading scales. Comparison of baseline demographics, early neurological improvement, and independence at 90 days was performed. Results— A significant difference in early neurological improvement was observed between 2b and 3 ( P =0.032), as well as between 2b and 2c ( P =0.028) under the mTICI 2c grading scale. Similarly, a significant difference in functional independence was observed between 2b and 3 ( P =0.037), as well as between 2b and 2c ( P =0.047) under the mTICI 2c scale. The difference in early neurological improvement or functional independence between 2b and 3 for the original TICI and mTICI scales was not significant. When combining the 2c and 3 groups under the mTICI 2c scale, there were significant differences between 2b and 2c/3 in regards to both early neurological improvement ( P =0.011) and independence ( P =0.018). Conclusions— Using a TICI grading system that includes an additional category beyond TICI 2b allows for refined prediction of early neurological improvement and functional independence.

Introduction There is very limited data on the use of MRI based perfusion imaging to select patients with acute ischemic stroke and large vessel occlusion (LVO) for intraarterial therapy beyond 6h from onset. Our aim is to report the outcome of patients with acute ischemic stroke and large artery occlusion who presented beyond 6h from onset, had favorable MRI imaging profile, and underwent mechanical embolectomy. Methods This is a single institution (Rhode Island Hospital) retrospective study between December 1st, 2015, and July 30th, 2016 that included patients with acute ischemic stroke and proximal LVO with CT ASPECTS of 6 or more and 6–24h from symptom onset who were assessed for mechanical embolectomy using MRI based perfusion imaging. Favorable imaging profile was defined based on prior studies as 1) DWI lesion volume (as defined as apparent diffusion coefficient –6 mm 2 /s) of 70ml or less; 2) Penumbra volume (as defined by volume of tissue with T max >6s) of 15ml or greater; 3) A mismatch ratio of 1.8 or more; and 4) Volume of tissue with perfusion lesion with T max >10s is Results 41 patients met the inclusion criteria; 22 (53.7%) had favorable imaging profile and underwent mechanical embolectomy. The rate of good outcomes in this series was similar to that in a patient level pooled meta-analysis of the recent endovascular trials (63.6% vs. 46%, p=0.13). None of the patients in our cohort had symptomatic intracereberal hemorrhage. Conclusions MRI perfusion based imaging may help select patients with acute ischemic stroke and proximal emergent LVO for embolectomy beyond the treatment window used in most endovascular trials. This provides compelling evidence for stroke centers to participate in ongoing trials using advanced imaging to study endovascular treatment in this patient population.

Background and purpose The current left atrial appendage (LAA) classification system (cLAA-CS) categorizes it into 4 morphologies: chicken wing (CW), windsock, cactus, and cauliflower, though there is limited data on either reliability or associations between different morphologies and stroke risk. We aimed to develop a simplified LAA classification system and to determine its relationship to embolic stroke subtypes. Methods Consecutive patients with ischemic stroke from a prospective stroke registry who previously underwent a clinically-indicated chest CT were included. Stroke subtype was determined and LAA morphology was classified using the traditional system (in which CW = low risk) and a new system (LAA-H/L, in which low risk morphology (LAA-L) was defined as an acute angle bend or fold from the proximal/middle portion of the LAA and high risk morphology (LAA-H) was defined as all others). As a proof of concept study, we determined reliability for the two classification systems, and we assessed the associations between both classification systems with stroke subtypes in our cohort and previous studies. Results We identified 329 ischemic stroke patients with a qualifying chest CT (126 cardioembolic subtype, 116 embolic stroke of undetermined source (ESUS), and 87 non-cardioembolic subtypes). Intra- and inter-rater agreements improved using the LAA-H/L (0.95 and 0.85, respectively) vs. cLAA-CS (0.50 and 0.40). The LAA-H/L led to classifying 69 LAA morphologies that met criteria for CW as LAA-H. In fully adjusted models, LAA-H was associated with cardioembolic stroke (OR 5.4, 95%CI 2.1–13.7) and ESUS (OR 2.8 95% CI 1.2–6.4). Non-CW morphology was also associated with embolic stroke subtypes, but the effect size was much less pronounced. Studies using the cLAA-CS yielded mixed results for inter- and intra-rater agreements but most showed an association between a non-CW morphology and stroke with no difference among the three non-CW subtypes. Conclusion The LAA-H/L classification system is simple, has excellent intra and inter-rater agreements, and may help risk identify patients with cardioembolic stroke subtypes. Larger studies are needed to validate these findings.

Background: Outpatient cardiac monitoring for 30 days or longer increases detection rates of paroxysmal atrial fibrillation (AF) after cryptogenic stroke, but the ideal duration of monitoring remains unclear. Two commonly used methods of prolonged outpatient cardiac monitoring are 30-day continuous telemetry and insertable cardiac monitors (ICM). We aim to compare rates of AF detection and recurrent stroke between patients with Embolic Stroke of Unknown Source (ESUS) monitored for approximately 30 days (short term) vs. beyond 30 days with ICM (long term). Methods: We analyzed a single center retrospective cohort of patients discharged with a diagnosis of ESUS over a two-year period. Patients were divided into two groups based on implemented cardiac monitoring method: short-term (30-day non-invasive monitor) and long-term (ICM Results: We identified 117 ESUS patients; 71 patients underwent short-term monitoring and 46 patients underwent long-term monitoring. After a median follow-up of 259 days (IQR 166-468 days), AF was detected in 11.2% (8/71) of patients undergoing short-term cardiac monitoring and 19.6% (9/46) of patients on long-term monitoring; 77.8% of AF was detected beyond 30 days. Recurrent stroke occurred in 12.8% (15/117) of patients. Rates of recurrent stroke were lower in patients undergoing long-term cardiac monitoring vs. only short-term monitoring [adjusted hazard ratio 0.12, 95% confidence interval 0.02-0.89, p = 0.038]. Conclusion: In a real world ESUS patient cohort, long term monitoring was associated with increased detection of AF and reduced risk of recurrent stroke. Large multicenter prospective studies are needed to confirm our findings.

Background: The left atrial appendage (LAA) is the main source of thrombus in atrial fibrillation (AF); biomarkers of LAA dysfunction are associated with ischemic stroke (IS) risk in patients with AF. We hypothesized that high risk LAA features [High risk morphology (LAA-H), LAA volume (LAAV), and LAA orifice surface area (LAAOSA)] would be more prevalent among patients with cardioembolic (CE) stroke and embolic stroke of undetermined source (ESUS) than among those with non-cardioembolic stroke (NCS). Methods: Consecutive patients with IS from a prospective comprehensive stroke center registry who previously underwent a clinically-indicated qualifying chest CT were included. Patients underwent inpatient diagnostic evaluation for ischemic stroke, and stroke subtype was determined based on ESUS criteria. LAA morphology [Low risk morphology was defined as two lobes with an acute angle between them or chicken wing morphology and LAA-H defined as all others], LAAOSA (measured in a plane parallel to the left atrium), and LAAV (measured using a volumetric analysis software) were determined using contrast enhanced thin-slice chest CT (≤2.5 mm thickness) by investigators blinded to stroke subtype. Results: Of 1234 patients with ischemic stroke, 329 (26.7%) patients had a qualifying chest CT performed (126 CE, 116 ESUS, and 87 NCS). The baseline characteristics of patients with and without chest CT were similar. When compared to NCS, LAA-H was more prevalent in ESUS (86.4% vs. 70.1%, p=0.018) and CE stroke (82.5% vs. 70.1%, p=0.042). The LAAOSA and volume did not significantly differ between the 3 groups (Table). Conclusion: LAA characteristics associated with cardioembolic stroke are also more prevalent in patients with ESUS. Larger studies are needed to confirm that LAA features are a risk factor for stroke among patients without AF, and whether anticoagulation is effective in patients with high-risk LAA features.

BackgroundFollowing the results of randomized clinical trials supporting the use of mechanical thrombectomy (MT) with tissue plasminogen activator for emergent large vessel occlusion (ELVO), our state Stroke Task Force convened to: update legislation to recognize differences between Primary Stroke Centers (PSCs) and Comprehensive Stroke Centers (CSCs); and update Emergency Medical Services (EMS) protocols to triage direct transport of suspected ELVO patients to CSCs.PurposeWe developed a single-session training curriculum for EMS personnel focused on the Los Angeles Motor Scale (LAMS) score, its use to correctly triage patients as CSC-appropriate in the field, and our state-wide EMS stroke protocol. We assessed the effect of our training on EMS knowledge.MethodsWe assembled a focus group to develop a training curriculum and assessment questions that would mimic real-life conditions under which EMS personnel operate. Ten questions were formulated to assess content knowledge before and after training, and scores were compared using generalized mixed models.ResultsTraining was provided for 179 EMS providers throughout the state.Average pre-test score was 52.4% (95% CI 49% to 56%). Average post-test score was 85.6% (83%–88%, PConclusionsA brief educational intervention results in substantial improvements in EMS knowledge of prehospital stroke severity scales and severity-based field triage protocols. Further study is needed to establish whether these gains in knowledge result in improved real-world performance.

Objectives Mechanical thrombectomy is the standard of care for stroke caused by an emergent large vessel occlusion in the anterior circulation, and the ability to rapidly review CTA is one hurdle in minimizing the time from diagnosis to intervention. We evaluated the diagnostic accuracy and confidence in review of stroke CTA for ELVO via a smartphone-based application as compared to PACS workstation. Patients and Methods Seventy-six head and neck CTA studies performed for stroke from one comprehensive and seven primary stroke centers were independently reviewed remotely on smartphone by two blinded interventional neuroradiologists in actual-use circumstances. The presence and location of large vessel occlusion(s), diagnostic quality, and confidence in interpretation were recorded. Comparison was made to blinded PACS workstation review performed at a delayed interval. Weighted Kappa and Kendall’s Tau statistics were calculated to evaluate intra- and inter-observer reliability. Results Of the 76 studies, 20 (26%) had a large vessel occlusion. 14 M1 segment occlusions (18%); 2 ICA terminus (3%); 2 tandem carotid and M1 (3%); and 2 basilar artery (3%). There was 100% diagnostic accuracy by both PACS workstation and smartphone review (p = .9999) with high inter- and intra-rater reliability for assessments of both image quality and diagnostic confidence. Conclusion In actual-use circumstances, experienced neuroradiologists can diagnose ELVOs on CTA using a smartphone application as accurately as on PACS workstation without degradation of confidence. These findings support the use of mobile electronic devices by stroke centers to rapidly triage patients for mechanical thrombectomy.

Background: Following the results of randomized clinical trials supporting the use of mechanical thrombectomy (MT) with tPA for large vessel occlusion (LVO) stroke, our state Stroke Task Force convened to 1) update legislation to recognize differences between Primary Stroke Centers (PSCs) and Comprehensive Stroke Centers (CSCs) and (2) update EMS protocols to triage direct transport of suspected LVO patients to CSCs. Objectives: Develop an assessment and single-session training curriculum to assess EMS knowledge before and knowledge gained after training on Los Angeles Motor Scale (LAMS) score, its use to correctly triage patients as CSC-appropriate, and our state-wide EMS protocol for stroke. We also aim to share our specific approach and its efficacy with others so our work can be disseminated and implemented elsewhere. Methods: We assembled a focus group to develop assessment questions that would mimic real-life conditions EMS personnel operate under. Ten identical pre-post training questions were formulated to assess content provided during the trainings. Content validity was established by ensuring that questions exclusively tested the content of the slides in the training. Results: Trainings were provided for 354 EMS professionals throughout the state. Average pre-test score was 52.4% (95% CI 49%-56%). Average post-test score was 85.6% (83%-88%), representing a significant increase. Each of the 10 questions were individually assessed and all showed significant gains in EMS knowledge after training (Figure 1, p Conclusions: Structured EMS education can improve knowledge of stroke triage protocols. As EMS protocols are changed to improve triage of suspected LVO patients to CSCs, such educational efforts will be critical to improve compliance.

Introduction: Higher rates of recanalization following thrombectomy are associated with better clinical outcomes. Specifically, patients with TICI 2c or 3 recanalization have higher degrees of functional independence as compared with TICI 2b recanalization. Older age is also associated with worse outcomes. We sought to determine if the magnitude of difference in outcomes between TICI 2c/3 and 2b is affected by age. Methods: We identified 157 consecutive patients with anterior circulation LVO over 24 months at a single center. Angiograms were reviewed blinded to clinical outcome. In 24 patients, TICI 2b or greater recanalization could not be achieved. This left 133 patients for analysis, with TICI 2c/3 recanalization in 72, and TICI 2b in 61. Primary outcome measures were independence (defined as mRs 0-2 at 90 days), and Utility weighted Rankin at 90 days. We analyzed the relationship between age and outcomes, comparing the TICI 2c/3 vs. 2b groups. Results: Patient age ranged from 19 to 92, median 73 (IQR 61-82). Median NIHSS was 17 (IQR 13-20). Median [IQR] time from imaging to reperfusion was 106 [80-141.5] minutes in the TICI 2c/3 group and 124 [86-150] minutes in the TICI 2b group, and did not increase with age. When comparing the relationship between age and outcomes, there was a greater decrease in functional outcome in those with TICI 2b versus TICI 2c/3 reperfusion. In patients younger than 70, 19/29 (66%) with TICI 2b achieved independence at 90 days, as compared with 19/26 (73%) in the TICI 2c/3 group. In patients 70 and older, 9/32 (28%) with TICI 2b achieved independence at 90 days, as compared with 26/46 (57%) in the TICI 2c/3 group, a significant difference (p=.02). The relationship between age and utility weighted Rankin at 90 days is highly significant (p=.0067) and summarized in the figure. Conclusions: The additional benefit of TICI 2c/3 over TICI 2b increases significantly with age. Higher levels of recanalization may benefit older patients to a greater extent.

Background: Driving is a privilege which carries significant emotional and social value to patients, enabling increased independence. After ischemic stroke, residual deficits may prevent patients from driving. We aimed to identify factors predictive of return to driving after stroke. Methods: We abstracted data from our ischemic stroke database and included all patients with ischemic stroke from April 1 st , 2016 to March 31 st 2017 who were reported to have been driving prior to their stroke. Formal driving evaluations were performed, if deemed necessary by the treating physician. Follow-up information was obtained at 90 days and included whether patients had returned to driving. Patients were divided into two groups - those who returned to driving at 90 days vs. not driving at 90 days. We compared baseline demographics including age, vascular risk factors, NIHSS score, acute stroke treatment (mechanical thrombectomy and IV thrombolysis), stroke subtype determined based on ESUS criteria, and hospital acquired-infections, hospital readmission rate. Results: We identified 282 patients with ischemic stroke who were driving prior to their stroke; 149 patients (52.8%) returned to driving at 90 days. On univariate analyses, patients who returned to driving were more likely to be younger (62.5 ± 15.1 years vs 70.6 ± 13.5 years; p Conclusion: In patients with ischemic stroke, younger age and lower 24-hour NIHSS predict return to driving after ischemic stroke. Larger studies are needed to confirm our findings.

Background: Current guidelines recommend mechanical thrombectomy for patients with anterior circulation proximal large vessel occlusion (LVO), NIHSS≥ 6, within 6 hours from symptom onset, with a NCCT ASPECTS of 6 or higher. It remains unclear whether patients with NIHSS < 6 and LVO should also undergo mechanical thrombectomy. The benefit of intervention, associated risk and predictors of outcome in this patient population has not been studied. We sought to determine the natural history and predictors of good outcome in patients NIHSS Methods: We abstracted data from our ischemic stroke prospective database and included patients with NIHSS < 6 and presence of proximal large vessel occlusion admitted between January 1 st , 2015 and April 30 th , 2017. The outcome, 90-day mRS, was collected via a phone call at 90 days. Patients were divided into two groups: good outcome (90-day mRS 0-1) and poor outcome (90-day mRS 2-6). We compared baseline demographics, treatments, neuroimaging data (ASPECTS score), and vascular imaging findings (location of occlusion, collateral score: poor, good, and excellent) between the two groups. P-value < 0.05 was considered significant. Results: A total of 68 patients were identified; 50/68 did not undergo mechanical thrombectomy; out of which only 25/50 (50%) had a good 90-day outcome. Patients with a good outcome were younger (Mean ± SD, 69.3 ±3.2 vs 76 ± 2.2 years of age, p=0.033) and had a lower median admission NIHSS score (3 vs. 4, p=0.026).There was a trend towards good outcome with ICA and M1- MCA occlusion when compared to other locations but this was not statistically significant. Other variables also did not achieve statistical significance. Conclusion: Younger age and lower NIHSS predict good functional outcome in patients with LVO and mild deficits. Larger prospective studies are needed to verify our findings and explore the role of mechanical thrombectomy in patients who might be at risk of poor outcome.

Background: The left atrial appendage (LAA) is the main source of thrombus in atrial fibrillation (AF), and there is an association between non-chicken wing (NCW) LAA morphology and stroke. We hypothesized that the prevalence of non-chicken wing LAA morphology would be higher among patients with cardioembolic (CE) stroke and embolic stroke of undetermined source (ESUS) than among those with non-cardioembolic stroke (NCS). Methods: This multi-center retrospective study included consecutive patients with ischemic stroke from three comprehensive stroke centers who previously underwent a qualifying chest CT. Patients underwent inpatient diagnostic evaluation for ischemic stroke, and stroke subtype was determined based on ESUS criteria. LAA morphology was determined using clinically performed contrast enhanced thin-slice chest CT by investigators blinded to stroke subtype. The primary predictor was NCW LAA morphology and the outcome was stroke subtype (CE, ESUS, NCS). Results: We identified 172 ischemic stroke patients who had a clinical chest CT performed. Mean age was 70.1±14.3 years and 51.7% were male. Compared to patients with NCS, the prevalence of NCW LAA morphology was higher in patients with CE stroke (58.7% vs. 46.3%, p=0.1) and ESUS (58.8% vs. 46.3%, p=0.2) but this difference did not achieve statistical significance. Conclusion: The prevalence of NCW LAA morphology is similar in patients with ESUS and CE, and may be higher than that in those with NCS. Larger studies are needed to confirm this association.

Background: Elevated cardiac troponin is a marker of cardiac disease and has been recently shown to be associated with embolic stroke risk in the general population. In the acute stroke setting, we hypothesize that elevated troponin levels are more prevalent in patients with embolic stroke subtypes [cardioembolic (CE) and embolic stroke of unknown source (ESUS)] as opposed to known non cardioembolic subtypes (NE) (large vessel disease, small vessel disease, and other). Methods: We abstracted data from our prospective stroke database and included all patients with ischemic stroke over a 22 month period. We defined positive troponin as ≥ 0.1 ng/mL. Patients diagnosed with acute myocardial infarction were excluded (n = 3).We compared clinical, laboratory and echocardiographic findings, and stroke subtypes using ESUS criteria between the two groups: Troponin+ and Troponin-. Results: We identified 1231 patients; 1129 had troponin levels available and 10.0% (113/1129) were trop+. On univariate analyses, Troponin+ patients were more likely to be older (77.4 ± 12.6 vs. 70.8 ± 15.0, p Conclusion: Elevated troponin levels in ischemic stroke is independently associated with a cardiac embolic source. Studies are needed to test anticoagulation vs. antiplatelet in patients with ESUS and elevated troponin.

Background: Hospital readmissions carry significant burden on both patients and providers, and may be preventable by appropriate identification of high-risk patients. In this study, we aimed to identify factors predictive of hospital readmission following ischemic stroke. Methods: We abstracted data from our ischemic stroke database and included all patients with ischemic stroke from April 1 st , 2016 to March 31 st 2017. Follow-up information was obtained at 90 days and included whether patients had been readmitted to Rhode Island Hospital. Patients were divided into two groups - those who had been readmitted at 90 days vs. not readmitted at 90 days. We compared baseline demographics including age, vascular risk factors, NIHSS score, acute stroke treatment (mechanical thrombectomy and IV thrombolysis), stroke subtype determined based on ESUS criteria, and hospital acquired-infections, hospital readmission rate. Results: We identified 600 patients with ischemic stroke; 185 patients (30.8%) were readmitted at 90 days. On univariate analyses, readmitted patients were more likely to have a higher 24-hour NIHSS (3 vs 2; p=0.007), and more likely to have hypertension (82.0% vs 72.9%; p=0.021), atrial fibrillation (36.6% vs 23.8%; p=0.002), congestive heart failure (14.7% vs 5.8%; p=0.001), large vessel occlusion (54.5% vs 43.8%; p=0.033), and cardioembolic stroke subtype (36.4% vs 25.3%). Moreover, readmitted patients were less likely to have cryptogenic stroke subtype (31.8% vs 44.1%; p=0.006). On regression models, hypertension (adjusted OR 1.78; 95% CI 1.02-3.10, p=0.043), atrial fibrillation (adjusted OR 3.12; 95% CI 1.08-9.00, p=0.035), congestive heart failure (adjusted OR 2.80; 95% CI 1.29-6.06, p=0.009), and cardioembolic stroke subtype (adjusted OR 0.32; 95% CI 0.10-0.98, p=0.046) were predictive of hospital readmission at 90 days. Conclusion: Nearly 30% of patients admitted with ischemic stroke are re-admitted in the next 90 days. Efforts to identify causes of re-admission particularly among high risk patients are needed to reduce the re-admission rates among stroke patients.

Background: Biomarkers to predict anticoagulation failure in patients with atrial fibrillation (AF) may help identify high-risk AF patients for further study. We hypothesize that left atrial enlargement (LAE) is more prevalent in AF patients admitted with ischemic stroke who are therapeutic, as opposed to non-therapeutic (NT), on anticoagulation. Methods: We included consecutive patients with AF admitted with a diagnosis of ischemic stroke between April 1 st , 2015 and December 31 st , 2016. Patients were divided into two groups based on whether they were therapeutic (warfarin with international normalized ratio ≥ 2.0 or non-vitamin K oral anticoagulant with uninterrupted use in the prior 2 weeks) vs. non-therapeutic on anticoagulation. We compared clinical and imaging characteristics, cardiac data (left atrial diameter on transthoracic echocardiogram), and outcomes (discharge modified Rankin Scale, discharge disposition, and symptomatic intracranial hemorrhage [sICH]) between the two groups. Multivariable logistic regression was used to estimate associations between therapeutic anticoagulation and variables, including CHADS 2 score and LAE (none/mild vs. moderate/severe). Results: We identified 225 patients; 52 (23.1%) were therapeutic on anticoagulation. The baseline demographics and risk factors were similar between the two groups. Patients therapeutic on anticoagulation were more likely to have a larger left atrial diameter (45.6 ± 9.2 vs. 42.3 ± 8.6 mm, p = 0.032), a higher CHADS2 score (2.9 ± 1.1 vs. 2.4 ± 1.1, p = 0.03), and sICH (13.5% vs. 3.5%, p = 0.013). After adjusting for the CHADS 2 score, patients who had stroke despite therapeutic anticoagulation were more likely to have moderate to severe LAE (odds ratio 2.05, 95% confidence interval 1.01-4.16). Results were unchanged when the CHA 2 DS 2 -VASc score was used. Conclusion: LAE is associated with anticoagulation failure in AF patients admitted with an ischemic stroke. This provides indirect evidence that LAE may portend failure of anticoagulation therapy in patients with AF; further studies are needed to delineate the significance of this association and improve stroke prevention strategies.

Background: Early neurological deterioration (END) prompting urgent brain imaging occurs in up to 15% of ischemic stroke patients receiving intravenous tissue plasminogen activator (tPA). Most of these are not related to symptomatic intracranial hemorrhage (sICH) but lead to unnecessary interruption of the tPA infusion. We aim to determine predictors of sICH in ischemic stroke patients undergoing emergent brain imaging after tPA. Methods: We queried our prospective stroke database and included all patients who received tPA for ischemic stroke from March 1 st , 2015 until March 1 st , 2017. We then identified patients who underwent emergent brain imaging before the planned 24-hour brain imaging and divided these patients into: sICH+ and sICH- defined by NINDS criteria. We compared baseline clinical factors, pre-admission medications, admission blood pressure, symptoms prompting repeat scan [change in level of consciousness (LOC); worsening or new (W/N) neurological symptoms without change in LOC; headache/nausea/vomiting), thrombectomy, 24-hour NIHSS and 90 day outcome. Results: We identified 511 patients who received tPA (sICH rate 4.1%). Emergent repeat brain CT was performed on 108 (21.1%); 17.5% (19/108) had sICH and 21.3% (23/108) occurred during the tPA infusion with only one being related to sICH. The mean time from tPA infusion to symptoms prompting brain imaging in sICH was 7.3 ± 5.3 hours. In patients who underwent emergent brain imaging, sICH+ patients were older (80.2 ± 15.8 vs. 70.8 ± 15.4, p = 0.026), with higher admission NIHSS (14 vs. 7, p = 0.0016) and 90-day mortality (87.5% vs. 22.4%, p Conclusion: Nearly 95% of patients with ischemic stroke had unnecessary interruption of the tPA infusion for new symptoms shortly after the tPA infusion. A change in LOC was the only predictor of sICH among tPA patients undergoing emergent brain imaging. In this group of patients, the preparation of tPA reversal agents awaiting brain imaging may help reduce tPA reversal times and improve outcomes

Importance: Large vessel disease (LVD) stroke subtype carries the highest risk of early recurrent stroke, reaching up to 30% in the first few days. Predictors of early recurrence have been previously described, but less is known regarding infarct expansion and other causes of neurological worsening. We aim to determine the association between impaired perfusion and neurological decline in patients with LVD subtype. Methods: This is a single center retrospective cohort study of all consecutive patients 18 years or older with LVD admitted with a diagnosis of ischemic stroke within 24 hours from symptom onset (12/1/2016 to 3/31/2017). Patients with 1) evidence of ≥ 50% stenosis of a large intra- or extracranial artery on computerized tomography angiography (CTA); 2) symptoms referable to the territory of the affected artery and NIHSS < 15 and 3) perfusion imaging data using the RAPID processing software were included. The primary predictor was unfavorable mismatch volume ≥15 mL, defined as perfusion deficit of Tmax > 6sec volume minus infarct volume similar to neuro-interventional trials. The outcome was recurrent cerebrovascular events (RCVE) at 90 days (adjudicated independently by two vascular neurologists) defined as a decline in neurologic function in the absence of a medical cause, or new infarct or infarct extension in the territory of the affected artery. We estimated the hazard ratio (HR) and 95% confidence interval (CI) for unfavorable perfusion imaging as predictor of RCVE using univariable and multivariable Cox proportional hazards models. Results: Sixty-eight patients met our inclusion criteria (mean age 64.7 years; 61.8% male; 58.8% intracranial LVD). When compared to patients without RCVE, patients with RCVE were more likely to have unfavorable mismatch volume [71.4% vs. 14.8%, p Conclusion: Perfusion mismatch is associated with RCVE in patients with ischemic stroke due to LVD. Pursuit of more aggressive treatment and management strategies may be warranted in this population.

Introduction: Treatment for large vessel occlusion is profoundly time dependent. Two potential mechanisms to reduce time to treatment are optimizing transfers from Primary Stroke Centers (PSC) and transporting selected patients directly to a Comprehensive Stroke Center (CSC). In our region, we sequentially implemented both interventions. We sought to evaluate the impact of 1) Optimization of PSC transfer protocols and 2) implementation of a severity based EMS triage protocol on times to treatment and outcomes. Methods: All thrombectomy patients in our state treated over 24 months were retrospectively reviewed. We included patients with anterior circulation LVO, presenting within 6 hours, with an NIHSS of 6 or higher. An EMS protocol was introduced such that patients with a field LAMS score of 4 or higher, within 30 minutes of the CSC, would be directly transported to the CSC. Patients from adjacent states (where the EMS protocol would not apply) as well as inpatient strokes were excluded. We examined the proportion of patients who were directly transported to the CSC, as well as trends in time to treatment with IV tPA and thrombectomy from the time of first hospital arrival (PSC or CSC). Time periods were as follows: 7/1/2015 to 12/31/2015 (Pre-optimization and pre-triage); 1/1/2016 to 12/31/2016 (PSC optimization; pre-triage) and 1/1/2017 to 6/30/2017 (PSC optimization and triage). Primary outcome measures were times to treatment, discharge to home, and in-hospital mortality. Results: The results are summarized in the table below. Marked decreases in median time from first hospital arrival to recanalization were seen, from 156 to 109 minutes over time. In addition, there were increases in discharge home, and decreases in in-hospital mortality across each of the time periods. Conclusions: Through a combination of field triage and optimization of PSC workflow, it is possible to reduce times to thrombectomy and improve outcomes across an entire region.

Introduction: All eligible patients receive IV tPA prior to thrombectomy, but the effect of IV tPA on recanalization prior to and following thrombectomy remains unclear. The purpose of this analysis was to determine the effect of IV tPA on early recanalization obviating the need for thrombectomy, as well as the effect of tPA on recanalization rates. Methods: All patients with a CTA-proven LVO in the ICA, M1, proximal M2, or basilar artery in whom thrombectomy was planned over a 24 month period were included. CTA was performed at the first presenting hospital, whether PSC or CSC, and not repeated on arrival for transfer patients. We defined “successful” treatment with IV tPA as TICI 2b or 3 reperfusion, such that thrombectomy was not performed. Time from tPA to start of angiography was divided into 30 minute intervals. We also examined the effect of transfer status and the relationship between tPA and overall recanalization after thrombectomy. Results: We identified 310 patients, 190 who received tPA prior to planned thrombectomy and 120 who did not. Of all patients, 178 (57%) were transfers, including 111/190 (58%) in the tPA group. The rates of recanalization with IV tPA are summarized in Table below. Overall rates of successful recanalization (TICI 2b or better) before thrombectomy are low, especially when time between IV tPA and start of angiography is minimized. Successful tPA recanalization rates were 11.7% for transfer patients and 6.3% for non-transfer patients, likely due to faster workflow at the comprehensive stroke center. The rates of overall successful recanalization (TICI 2b or better) were 77.4% in the tPA group (23.8% TICI 2b; 53.6% TICI 2c/3) and 83.6% (22.4% TICI 2b; 61.2% TICI 2c/3) in the no tPA group. Conclusion: Early recanalization rate following IV tPA prior to thrombectomy is low, especially when workflow is optimized to minimize time between tPA bolus and start of angiography. Pre-treatment with IV tPA did not increase recanalization rates after thrombectomy.

Introduction: We have previously shown that a transfer protocol for patients with suspected large vessel occlusion (LVO) stroke which includes early vessel imaging at the Primary Stroke Center (PSC) is associated with decreased onset to recanalization times driven entirely by improved initial hospital processes at the PSC and reflected in the PSC Door-in Door-out (DIDO) time. In this study, we examined the association between DIDO and outcomes. Methods: We collected prospective data on 195 patients transferred to our Comprehensive Stroke Center (CSC) with PSC-confirmed LVO between July 1, 2015 and June 30, 2017. The patients were accepted from 2 states and 16 different PSCs (only 2 of which were part of our hospital system) and the furthest PSC being 56 miles away. We included all patients with LVO stroke (ICA, M1, Basilar) with an NIHSS of 6 or higher. We examined PSC workflow factors associated with shorter DIDO times. Outcomes were examined by DIDO using generalized mix modeling assuming a binomial distribution with SAS 9.4. Results: The median [IQR] age and NIHSS of the 195 ELVO transfers was 75 [62-84] and 17 [12-22]. IV tpA was administered to 64% of patients. Regarding specific workflow metrics, Median [IQR] times (in minutes) for PSC door to CT was 12 [9-20], PSC door to CTA 26 [19-50], PSC door to tPA 58 [46-78], DIDO 87 [68-113], PSC door to CSC groin puncture 140 [115-179], and PSC door to CSC recanalization of 169 [136-216]. As can be seen in the Figure, longer DIDO were associated with more deleterious scores on discharge NIHSS (p=0.04), discharge mRS (p=0.009) and 90d mRS (p=0.002). Full execution of the PSC LVO protocol and “hold, drip and go” strategy for EMS transport were associated with shorter DIDO times. Conclusion: For patients diagnosed with LVO at a PSC, longer DIDO time appears to have a deleterious effect on outcome at discharge from the CSC and at 90 days. All PSCs should take measures to decrease DIDO and use it as a quality metric.

Background: Recent studies have shown that outpatient cardiac monitoring for 30 days or longer increases detection rate of paroxysmal atrial fibrillation (AF) after Embolic Stroke of Unknown Source (ESUS). For patients with AF detected on monitoring, anticoagulation can be initiated to reduce risk of recurrent stroke. In this study, we aim to compare characteristics between patients who received cardiac monitoring and those who did not to further elucidate trends in the use of prolonged outpatient cardiac monitoring following ESUS. Methods: We analyzed a retrospective cohort of patients discharged with a diagnosis of ESUS over a period of 18 months in whom outpatient cardiac monitoring was ordered. Patients who were deceased or without follow-up at 90 days were excluded. Patients were divided into two groups based on whether or not they received outpatient cardiac monitoring. We compared demographic data, clinical risk factors, and NIHSS between the two groups. Results: Out of 282 patients with ESUS, 189 (67.0%) patients had 90 day follow-up data available; 118 (62.4%) underwent cardiac monitoring and 71 (37.6%) did not undergo cardiac monitoring. Of the patients who were monitored, 81.4% (96/118) received a 30 day non-invasive monitor and 43.2% (51/118) patients had an ICM implanted. There were no significant differences in baseline characteristics among patients who underwent cardiac monitoring versus those who did not. Conclusion: More than one-third of patients with ESUS for whom outpatient cardiac monitoring was recommended and ordered did not actually receive it. This finding supports the need for more convenient, effective processes by which patients can follow through with outpatient cardiac monitoring which could perhaps be initiated at discharge.

Introduction: Since the treatment effect of mechanical thrombectomy (MT) is profoundly time-dependent, we created an optimized Comprehensive Stroke Center-Large Vessel Occlusion (CSC-LVO) protocol focusing on three key steps: early vessel imaging on all code stroke patients, standardizing the MT procedure, and integrating a team of stroke-dedicated advanced practice clinicians (APCs) to manage patients across the continuum of initial hospital care. Methods: All direct to CSC (“mothership”) LVO patients treated during the following time periods (Epochs) were retrospectively reviewed: 1/1/2015 to 6/30/2015 (Pre-optimization); 1/1/2016 to 6/30/2016 (Early Vessel Imaging and MT standardization) and 1/1/2017 to 6/30/2017 (Early Vessel Imaging, MT standardization, APC integration). Epochs were separated by 6 months to minimize any “ramp-up” effect. We included all patients who presented with large vessel occlusion stroke (ICA, M1, Basilar), within six hours from symptom onset, and with an NIHSS of 6 or higher. During Epoch 3, APCs were available for 12h/day and 7 days a week. For all cases, the neurointerventional team was activated only after the CTA confirmed large vessel occlusion. To measure efficiency of initial hospital processes, we compared CSC door to CT, door to CTA, door to IV t-PA, door to groin puncture, and door to recanalization across time Epochs. Results: All results are summarized in the table below and there was a marked decrease in median time from CSC arrival to recanalization from 186 to 100 minutes. Within Epoch 3, when APCs were in-house (n=29/44 or 70% of cases), the median [IQR] Door to t-PA, door to groin puncture, and door to recanalization times were lowest 27 [23-31], 53 [42-73], and 86 [72-118] minutes, respectively. Conclusions: A CSC-LVO protocol including early vessel imaging, procedural standardization, and integrating a team of stroke-dedicated APCs enables CSCs to achieve median door to recanalization times in less than 90 minutes.

ObjectivesEarly neurological deterioration prompting urgent brain imaging occurs in nearly 15% of patients with ischaemic stroke receiving intravenous tissue plasminogen activator (tPA). We aim to determine risk factors associated with symptomatic intracranial haemorrhage (sICH) in patients with ischaemic stroke undergoing emergent brain imaging for early neurological deterioration after receiving tPA.MethodsWe abstracted data from our prospective stroke database and included all patients receiving tPA for ischaemic stroke between 1 March 2015 and 1 March 2017. We then identified patients with neurological deterioration who underwent urgent brain imaging prior to their per-protocol surveillance imaging and divided patients into two groups: those with and without sICH. We compared baseline demographics, clinical variables, in-hospital treatments and functional outcomes at 90 days between the two groups.ResultsWe identified 511 patients who received tPA, of whom 108 (21.1%) had an emergent brain CT. Of these patients, 17.5% (19/108) had sICH; 21.3% (23/108) of emergent scans occurred while tPA was infusing, though only 4.3% of these scans (1/23) revealed sICH. On multivariable analyses, the only predictor of sICH was a change in level of consciousness (OR 6.62, 95% CI 1.64 to 26.70, P=0.008).ConclusionChange in level of consciousness is associated with sICH among patients undergoing emergent brain imaging after receiving tPA. In this group of patients, preparation of tPA reversal agents while awaiting brain imaging may reduce reversal times. Future studies are needed to study the cost-effectiveness of this approach.

Background The left atrial appendage (LAA) is the main source of thrombus in atrial fibrillation, and there is an association between non-chicken wing (NCW) LAA morphology and stroke. We hypothesized that the prevalence of NCW LAA morphology would be higher among patients with cardioembolic (CE) stroke and embolic stroke of undetermined source (ESUS) than among those with noncardioembolic stroke (NCS). Methods This multicenter retrospective pilot study included consecutive patients with ischemic stroke from 3 comprehensive stroke centers who previously underwent a qualifying chest computed tomography (CT) to assess LAA morphology. Patients underwent inpatient diagnostic evaluation for ischemic stroke, and stroke subtype was determined based on ESUS criteria. LAA morphology was determined using clinically performed contrast enhanced thin-slice chest CT by investigators blinded to stroke subtype. The primary predictor was NCW LAA morphology and the outcome was stroke subtype (CE, ESUS, NCS). Results We identified 172 patients with ischemic stroke who had a clinical chest CT performed. Mean age was 70.1 ± 14.3 years and 51.7% were male. Compared with patients with NCS, the prevalence of NCW LAA morphology was higher in patients with CE stroke (58.7% versus 46.3%, P = .1) and ESUS (58.8% versus 46.3%, P = .2), but this difference did not achieve statistical significance. Conclusion The prevalence of NCW LAA morphology may be similar in patients with ESUS and CE, and may be higher than that in those with NCS. Larger studies are needed to confirm these associations.

While prehospital triage to the closest comprehensive stroke center (CSC) may improve the delivery of care for patients with suspected emergent large-vessel occlusion (ELVO), efficient systems of care must also exist for patients with ELVO who first present to a primary stroke center (PSC).To describe the association of a PSC protocol focused on 3 key steps (early CSC notification based on clinical severity, vessel imaging at the PSC, and cloud-based image sharing) with the efficiency of care and the outcomes of patients with suspected ELVO who first present to a PSC.In this retrospective cohort study, 14 regional PSCs unfamiliar with the management of patients with ELVO were instructed on the use of the following protocol for patients presenting with a Los Angeles Motor Scale score 4 or higher: (1) notify the CSC on arrival, (2) perform computed tomographic angiography concurrently with noncontract computed tomography of the brain and within 30 minutes of arrival, and (3) share imaging data with the CSC using a cloud-based platform. A total of 101 patients were transferred from regional PSCs to the CSC between July 1, 2015, and May 31, 2016, and received mechanical thrombectomy for acute ischemic stroke. The CSC serves approximately 1.7 million people and partners with 14 PSCs located between 6.4 and 73.6 km away. All consecutive patients with internal carotid artery or middle cerebral artery occlusions transferred over an 11-month period were reviewed, and they were divided into 2 groups based on whether the PSC protocol was partially or fully executed.The primary outcomes were efficiency measures including time from PSC door in to PSC door out, time from PSC door to CSC groin puncture, and 90-day modified Rankin Scale score (range, 0-6; scores of 0-2 indicate a good outcome).Although 101 patients were transferred, only 70 patients met the inclusion criteria during the study period. The protocol was partially executed for 48 patients (68.6%) (mean age, 77 years [interquartile range, 65-84 years]; 22 of the 48 patients [45.0%] were women) and fully executed for 22 patients (31.4%) (mean age, 76 years [interquartile range, 59-86 years]; 13 of the 22 patients [59.1%] were women). When fully executed, the protocol was associated with a reduction in the median time for PSC arrival to CSC groin puncture (from 151 minutes [95% CI, 141-166 minutes] to 111 minutes [95% CI, 88-130 minutes]; P .001). This was primarily related to an improvement in the time from PSC door in to door out that reduced from a median time of 104 minutes (95% CI, 82-112 minutes) to a median time of 64 minutes (95% CI, 51-71.0 minutes) (P .001). When the protocol was fully executed, patients were twice as likely to have a favorable outcome (50% vs 25%, P .04).When fully implemented, a standardized protocol at PSCs for patients with suspected ELVO consisting of early CSC notification, computed tomographic angiography on arrival to the PSC, and cloud-based image sharing is associated with a reduction in time to groin puncture and improved outcomes.

Background and purpose: The Thrombolysis in Cerebral Infarction (TICI) 2b classification is defined as “near complete” recanalization for acute ischemic stroke. While this category has historically combined with TICI 3 (“complete reperfusion”) as “successful recanalization”, recent studies have suggested that TICI 3 and a proposed intermediate TICI 2c (“near complete reperfusion except for slow flow or distal emboli”) should be distinguished from TICI 2b due to differences in outcomes. In this study, we examined if early neurologic improvement differed significantly between patients with TICI 2b, TICI 2c, and TICI 3 recanalization for emergent large vessel occlusions treated with mechanical thrombectomy (MT). Methods: Retrospective analysis was performed using data from 133 consecutive patients with middle cerebral artery or internal carotid artery occlusions treated with MT from January 2015 to June 2016. Patient angiograms were graded independently and blinded to clinical data by two experienced readers based on original TICI (oTICI), modified TICI (mTICI), and modified TICI with TICI 2c (mTICI 2c) grading scales. Early neurologic improvement was assessed using change in NIHSS by discharge. General linear modeling was used to evaluate difference in NIHSS delta scores between TICI scales with SAS/PROC GLIMMIX. Multiple comparisons were evaluated using Tukey corrections with significance established at the .05 level. Results: Without the TICI 2c category, there was not a significant difference in change in NIHSS observed between TICI 3 and TICI 2b for both the oTICI (delta 1.4, p=0.355) and mTICI scales (delta 2.1, p=0.190). However, when an additional category (TICI 2c) was added, there was a significant difference in change in NIHSS observed between TICI 3 and TICI 2b (delta 3.8, p= 0.026) as well as between TICI 2c and TICI 2b (delta 3.7, p=0.019). Conclusion: Utilizing a TICI recanalization grading system that adds an additional category beyond TICI 2b allows for improved prediction of neurological improvement in patients treated with MT. Higher levels of recanalization are associated with greater neurologic improvement.

Background: Atrial dysfunction or “cardiopathy” has been recently proposed as a mechanism in cryptogenic stroke. A prolonged PR interval may reflect impaired atrial conduction and thus may be a useful biomarker of atrial cardiopathy. We aim to compare the prevalence of PR interval prolongation in patients with cryptogenic stroke (CS) when compared to known non-cryptogenic non-cardioembolic stroke (NCNCS) subtypes. Methods: We retrospectively analyzed prospective ischemic stroke databases and included consecutive patients between December 1 st , 2013 and August 31 st , 2015 in three comprehensive stroke centers (Rhode Island Hospital, Hartford Hospital, and Tulane University Medical Center). Consecutive patients 18 years or older with a discharge diagnosis of ischemic non-cardioembolic stroke were included. The main outcome was ischemic stroke subtype (CS vs. NCNCS). We compared PR intervals as a continuous and categorical variable (< 200 ms; ≥ 200 ms) and other clinical and demographic factors between the two groups and used multivariate regression analyses including age and other factors deemed significant on univariate analyses to determine the association between PR interval prolongation and CS. Results: We identified 644 patients with ischemic non-cardioembolic stroke (224 CS and 420 NCNCS). The PR interval was longer in patients with CS vs NCNCS (175.4 ± 35.2 ms vs. 166.5 ± 27.7 p = 0.005). After adjusting for factors that were found to be significant in univariate analyses, a prolonged PR interval was independently associated with CS (Odds Ratio: 1.70; 95% CI 1.08-2.70; p=0.022). The association was more pronounced when excluding patients on atrio-ventricular nodal blocking agents (OR=2.64, 95% CI 1.44-4.83, p=0.002). Conclusions: A prolonged PR interval is associated with CS and may be a biomarker of atrial cardiopathy in patients with cryptogenic stroke. This association needs to be confirmed in prospective neuro-epidemiological cohorts.

Background: There is very limited data on the use of advanced neuroimaging to select patients with acute ischemic stroke and large vessel occlusion for intraarterial therapy beyond 6 hours from onset. Our aim is to report the outcome of patients with acute ischemic stroke and large artery occlusion who presented beyond 6 hours from onset, had favorable MRI imaging profile, and underwent mechanical embolectomy. Methods: This is a single institution retrospective study between December 1st, 2015, and July 30 th , 2016 with acute ischemic stroke and anterior circulation large vessel occlusion (LVO) with ASPECTS of 6 or more and beyond 6 hours from symptoms onset. Favorable imaging profile was defined as 1) DWI lesion volume (as defined as apparent diffusion coefficient < 620 X 10-6 mm2/s) of 70 mL or less AND 2) Penumbra volume (as defined by volume of tissue with Tmax >6 sec) of 15 mL or greater AND 3) A mismatch ratio of 1.8 or more AND 4) Volume of tissue with perfusion lesion with Tmax > 10 sec is less than 100 mL. Good outcome was defined as a 90 day mRS≤2. Results: In the study period, 41 patients met the inclusion criteria; 22 (53.6%) had favorable imaging profile and underwent mechanical embolectomy. The median age was 75 years (59-92), 68.2% were females; the median time from last known normal to groin puncture was 684.5 minutes (range 363-1628) and the median admission NIHSS score was 17.5 (range 4-28). The rate of good outcomes in this series was similar to that in a patient level pooled meta-analysis of the recent endovascular trials (68.2% vs. 46.0%, p=0.07). The rate of good outcome matches that of the EXTEND-IA trial that selected patients using perfusion imaging (68.2% vs. 71.0%, p = 1.00). None of the patients in our cohort had symptomatic intracereberal hemorrhage. Conclusion: Advanced MR imaging may help select patients with acute ischemic stroke and anterior circulation large vessel occlusion for embolectomy beyond the treatment window used in most endovascular trials.

Introduction: We created an optimized ELVO transfer protocol for PSCs focused on three key steps: early CSC notification based on clinical severity threshold, obtaining vessel imaging at the PSC, and cloud-based image sharing without the use of telemedicine. Methods: Our regional PSC spokes were educated to execute the following protocol for patients presenting with a Los Angeles motor score ≥4: 1) notify the CSC on arrival 2) obtain CTA at time of initial NCCT and within 30 minutes of PSC arrival, and 3) implement a secure cloud-based remote viewing platform (LifeIMAGE). We reviewed all ICA and/or M1 occlusions transferred over an 11 month period, and divided the patients into two groups: those for whom the protocol was executed and those for whom it was not. Time from PSC arrival to start of angiogram was modeled using Kaplan-Meier estimation, with Wilcoxon test given no observations were censored. Favorable outcome (mRs 0-2 at 90 days) was modeled by protocol using a generalized linear model with a binary distribution. Results: Between 7/1/15 to 5/31/16 there were 70 patients transferred for thrombectomy. When executed, the PSC ELVO protocol reduced the median time for PSC arrival to CSC groin puncture from 151 [141.0, 166.0] to 111 [88.0, 130.0] minutes, a significant reduction of 40 minutes, p Conclusion: A standardized process at PSCs for suspected ELVO patients consisting of early CSC notification, CTA on arrival to the PSC and image sharing is easily implemented and significantly reduces the time to CSC groin puncture and improves outcomes.

Background and purpose: We compared the value of Alberta Stroke Program Early Computed Tomographic scoring using CT (CT ASPECTS), collateral score on CT angiography (CTA), ASPECTS using diffusion-weighted MRI (DWI ASPECTS), DWI lesion volume, and DWI volume with National Institute of Health Stroke Scale (NIHSS) in determining candidacy of patients who presented >6 hours from stroke onset. Methods: Decision to treat was first determined for each test alone and then with knowledge from other tests. A dismantling design was used to determine the additive effects of each test. Any discrepancy between the first and subsequent decisions to treat, in terms of sensitivity and specificity, is the impact of gained knowledge and was assessed using a generalized mixed-model assuming a binary distribution with PROC GLIMMIX/SAS. Inter-rater reliability was examined using weighted-Kappa. Results: We identified 39 patients between December 1st, 2015 and June 30th 2016. Median time from last-known normal to non-contrast CT was 492 minutes. Median interval between non-contrast CT and CTA was 7 minutes, and between CTA and MRI, 75.5 minutes. For sensitivity, effect of knowledge gained from successive tests was not significant (Table 1; Fig. 1). However, significant gains in specificity were observed from successive tests (63% to 84%; p Conclusion: CT, CTA and MRI each have the ability to correctly determine ELVO patients who would be candidates for embolectomy. However, identification of poor candidates for endovascular therapy was significantly improved using diffusion-weighted MRI.

Atrial dysfunction or "cardiopathy" has been recently proposed as a mechanism in cryptogenic stroke. A prolonged PR interval may reflect impaired atrial conduction and thus may be a biomarker of atrial cardiopathy. We aim to compare the prevalence of PR interval prolongation in patients with cryptogenic stroke (CS) when compared with known non-cryptogenic non-cardioembolic stroke (NCNCS) subtypes.We used prospective ischemic stroke databases of 3 comprehensive stroke centers to identify patients 18 years or older with a discharge diagnosis of ischemic non-cardioembolic stroke between December 1, 2013 and August 31, 2015. The main outcome was ischemic stroke subtype (CS versus NCNCS). We compared PR intervals as a continuous and categorical variable (200 milliseconds; ≥200 milliseconds) and other clinical and demographic factors between the 2 groups and used multivariate regression analyses to determine the association between PR interval prolongation and CS.We identified 644 patients with ischemic non-cardioembolic stroke (224 CS and 420 NCNCS). Patients with CS were more likely to have a PR of 200 milliseconds or greater when compared with those with NCNCS (23.2% versus 13.8%, P = .009). After adjusting for factors that were significant in univariate analyses, a PR of 200 milliseconds or greater was independently associated with CS (odds ratio [OR] 1.70, 95% CI 1.08-2.70). The association was more pronounced when excluding patients on atrioventricular nodal blocking agents (OR 2.64, 95% CI 1.44-4.83).A PR of 200 milliseconds or greater is associated with CS and may be a biomarker of atrial cardiopathy in the absence of atrial fibrillation. Prospective studies are needed to confirm this association.

Biomarkers of atrial dysfunction or "cardiopathy" are associated with embolic stroke risk. However, it is unclear if this risk is mediated by undiagnosed paroxysmal atrial fibrillation or flutter (AF). We aim to determine whether atrial cardiopathy biomarkers predict AF on continuous heart-rhythm monitoring after embolic stroke of undetermined source (ESUS).This was a single-center retrospective study including all patients with ESUS undergoing 30 days of ambulatory heart-rhythm monitoring to look for AF between January 1, 2013 and December 31, 2015. We reviewed medical records for clinical, radiographic, and cardiac variables. The primary outcome was a new diagnosis of AF detected during heart-rhythm monitoring. The primary predictors were atrial biomarkers: left atrial diameter on echocardiography, P-wave terminal force in electrocardiogram (ECG) lead V1, and P wave - R wave (PR) interval on ECG. A multiple logistic regression model was used to assess the relationship between atrial biomarkers and AF detection.Among 196 eligible patients, 23 (11.7%) were diagnosed with AF. In unadjusted analyses, patients with AF were older (72.4 years versus 61.4 years, P .001) and had larger left atrial diameter (39.2 mm versus 35.7 mm, P = .03). In a multivariable model, the only predictor of AF was age ≥ 60 years (odds ratio, 3.0; 95% CI, 1.06-8.5; P = .04).Atrial biomarkers were weakly associated with AF after ESUS. This suggests that previously reported associations between these markers and stroke may reflect independent cardiac pathways leading to stroke. Prospective studies are needed to investigate these mechanisms.

BackgroundModern stent retriever-based embolectomy for patients with emergent large vessel occlusion improves outcomes. Techniques aimed at achieving higher rates of complete recanalization would benefit patients.ObjectiveTo evaluate the clinical impact of an embolectomy technique focused on continuous aspiration prior to intracranial vascular embolectomy (CAPTIVE).MethodsA retrospective review was performed of 95 consecutive patients with intracranial internal carotid artery or M1 segment middle cerebral artery occlusion treated with stent retriever-based thrombectomy over an 11-month period. Patients were divided into a conventional local aspiration group (traditional group) and those treated with a novel continuous aspiration technique (CAPTIVE group). We compared both early neurologic recovery (based on changes in National Institute of Health Stroke Scale (NIHSS) score), independence at 90 days (modified Rankin score 0–2), and angiographic results using the modified Thrombolysis in Cerebral Ischemia (TICI) scale including the TICI 2c category.ResultsThere were 56 patients in the traditional group and 39 in the CAPTIVE group. Median age and admission NIHSS scores were 78 years and 19 in the traditional group and 77 years and 19 in the CAPTIVE group. Median times from groin puncture to recanalization in the traditional and CAPTIVE groups were 31 min and 14 min, respectively (pConclusionsThe CAPTIVE embolectomy technique may result in higher recanalization rates and better clinical outcomes.