Thrombectomy-capable Centers Research Articles

Travel time and distance for bypass and non-bypass routing of stroke patients in the USA

BackgroundEndovascular thrombectomy is not available at all hospitals that offer intravenous thrombolysis, prompting debate regarding the preferred transport destination for acute ischemic stroke. This study aimed to quantify real-world travel...

Effect of Direct Transportation to Thrombectomy-Capable Center vs Local Stroke Center on Neurological Outcomes in Patients With Suspected Large-Vessel Occlusion Stroke in Nonurban Areas

In nonurban areas with limited access to thrombectomy-capable centers, optimal prehospital transport strategies in patients with suspected large-vessel occlusion stroke are unknown. To determine whether, in nonurban areas, direct transport to a thrombectomy-capable center is beneficial compared with transport to the closest local stroke center. Multicenter, population-based, cluster-randomized trial including 1401 patients with suspected acute large-vessel occlusion stroke attended by emergency medical services in areas where the closest local stroke center was not capable of performing thrombectomy in Catalonia, Spain, between March 2017 and June 2020. The date of final follow-up was September 2020. Transportation to a thrombectomy-capable center (n = 688) or the closest local stroke center (n = 713). The primary outcome was disability at 90 days based on the modified Rankin Scale (mRS; scores range from 0 [no symptoms] to 6 [death]) in the target population of patients with ischemic stroke. There were 11 secondary outcomes, including rate of intravenous tissue plasminogen activator administration and thrombectomy in the target population and 90-day mortality in the safety population of all randomized patients. Enrollment was halted for futility following a second interim analysis. The 1401 enrolled patients were included in the safety analysis, of whom 1369 (98%) consented to participate and were included in the as-randomized analysis (56% men; median age, 75 [IQR, 65-83] years; median National Institutes of Health Stroke Scale score, 17 [IQR, 11-21]); 949 (69%) comprised the target ischemic stroke population included in the primary analysis. For the primary outcome in the target population, median mRS score was 3 (IQR, 2-5) vs 3 (IQR, 2-5) (adjusted common odds ratio [OR], 1.03; 95% CI, 0.82-1.29). Of 11 reported secondary outcomes, 8 showed no significant difference. Compared with patients first transported to local stroke centers, patients directly transported to thrombectomy-capable centers had significantly lower odds of receiving intravenous tissue plasminogen activator (in the target population, 229/482 [47.5%] vs 282/467 [60.4%]; OR, 0.59; 95% CI, 0.45-0.76) and significantly higher odds of receiving thrombectomy (in the target population, 235/482 [48.8%] vs 184/467 [39.4%]; OR, 1.46; 95% CI, 1.13-1.89). Mortality at 90 days in the safety population was not significantly different between groups (188/688 [27.3%] vs 194/713 [27.2%]; adjusted hazard ratio, 0.97; 95% CI, 0.79-1.18). In nonurban areas in Catalonia, Spain, there was no significant difference in 90-day neurological outcomes between transportation to a local stroke center vs a thrombectomy-capable referral center in patients with suspected large-vessel occlusion stroke. These findings require replication in other settings. ClinicalTrials.gov Identifier: NCT02795962.

Assessing Thrombectomy Capacity and Characteristics of Thrombectomy Capable Centers World-wide Using the MT2020+ Global Thrombectomy Tracking Smartphone App (P12-10.005)

Assessing Thrombectomy Capacity and Characteristics of Thrombectomy Capable Centers World-wide Using the MT2020+ Global Thrombectomy Tracking Smartphone App (P12-10.005)

Should Primary Stroke Centers Perform Advanced Imaging?

Should Primary Stroke Centers Perform Advanced Imaging?

A novel emergency medical services protocol to improve treatment time for large vessel occlusion strokes.

In many systems, patients with large vessel occlusion (LVO) strokes experience delays in transport to thrombectomy-capable centers. This pilot study examined use of a novel emergency medical services (EMS) protocol to expedite transfer of patients with LVOs to a comprehensive stroke center (CSC). From October 1, 2020 to February 22, 2021, Indianapolis EMS piloted a protocol, in which paramedics, after transporting a patient with a possible stroke remained at the patient's bedside until released by the emergency department or neurology physician. In patients with possible LVO, EMS providers remained at the bedside until the clinical assessment and CT angiography (CTA) were complete. If indicated, the paramedics at bedside transferred the patient, via the same ambulance, to a nearby thrombectomy-capable CSC with which an automatic transfer agreement had been arranged. This five-month mixed methods study included case-control assessment of use of the protocol, number of transfers, safety during transport, and time saved in transfer compared to emergent transfers via conventional interfacility transfer agencies. In qualitative analysis EMS providers, and ED physicians and neurologists at both sending and receiving institutions, completed e-mail surveys on the process, and offered suggestions for process improvement. Responses were coded with an inductive content analysis approach. The protocol was used 42 times during the study period; four patients were found to have LVOs and were transferred to the CSC. There were no adverse events. Median time from decision-to-transfer to arrival at the CSC was 27.5 minutes (IQR 24.5-29.0), compared to 314.5 minutes (IQR 204.0-459.3) for acute non-stroke transfers during the same period. Major themes of provider impressions included: incomplete awareness of the protocol, smooth process, challenges when a stroke alert was activated after EMS left the hospital, greater involvement of EMS in patient care, and comments on communication and efficiency. This pilot study demonstrated the feasibility, safety, and efficiency of a novel approach to expedite endovascular therapy for patients with LVOs.

Abstract 26: Timing The Optimal Transfer Modality For Suspected Large-vessel Stroke Patients: A Post-hoc Analysis Of The Racecat Trial

Introduction: Current recommendations for regional stroke destination suggest that patients with an acute severe stroke should be triaged based on estimated time to arrival to a thrombectomy-capable center. We aimed to evaluate which time period available at the time that patient is triaged is able to discriminate which transfer modality should be chosen. Methods: We built and ordered logistic regression model adjusted for multiple comparisons with the RACECAT trial population using time periods available during triage: time from onset to emergency medical services (EMS) evaluation, estimated time of arrival to the thrombectomy-capable center and between centers distance. Estimated times were computed using a distance matrix API. Primary outcome was disability at 90 days, as assessed by the shift analysis on the modified Rankin score. Results: Of the 1369 patients evaluated, median time from onset to EMS evaluation, estimated time to arrival to the thrombectomy-capable center and between centers distances were 65 minutes (interquartile ratio (IQR) 43 to 138), 61 minutes (IQR 36 to 80) and 62 minutes (IQR 36 to 73), respectively. In patients transferred to local stroke centers, delay in EMS evaluation was associated with higher degrees of disability (for each 30 minutes delay, adjusted common odds ratio (acOR) 1.035, 97.5% confidence interval (CI) 1.005 to 1.066), with no influence in patients directly transferred to thrombectomy-capable centers (for each 30 minutes delay, acOR 0.999, 97.5% CI 0.981 to 1.018) (p interaction =0.048). In patients evaluated by EMS above 120 minutes after stroke onset, direct transfer to a thrombectomy-capable center was associated with lower degrees of disability (acOR 1.494, 95% CI 1.026 to 2.174). Conclusion: In the RACECAT trial, delay in EMS evaluation was associated with higher degrees of disability in patients transferred to local stroke centers and may serve as a potential biomarker for prehospital triage optimization.

Abstract TP44: A Novel Emergency Medical Services Protocol To Improve Treatment Time For Large Vessel Occlusion Strokes

Objective: In many systems, patients with large vessel occlusion (LVO) strokes experience delays in transport to thrombectomy-capable centers. This pilot study examined use of a novel emergency medical services (EMS) protocol to expedite transfer of patients with LVOs to a comprehensive stroke center (CSC). Methods: From October 1, 2020 to February 22, 2021, one large urban EMS agency piloted a protocol, in which paramedics, after transporting a patient with a possible stroke remained at the patient’s bedside until released by the emergency department or neurology physician. In patients with possible LVO, EMS providers remained at the bedside until the clinical assessment and CT angiography (CTA) were complete. If indicated, the paramedics at bedside transferred the patient, via the same ambulance, to a nearby thrombectomy-capable CSC with which an automatic transfer agreement had been arranged. This five-month pilot assessed use of the protocol, number of transfers, safety during transport, and time saved in transfer compared to emergent transfers via conventional interfacility transfer agencies. EMS providers, and emergency department physicians and neurologists at both sending and receiving institutions, completed e-mail surveys on the process, and offered suggestions for process improvement. Responses were coded with an inductive content analysis approach. Results: The protocol was used 42 times during the study period; four patients were found to have LVOs and were transferred to the CSC. There were no adverse events. Median time from decision-to-transfer to arrival at the CSC was 27.5 minutes (IQR 24.5-29.0), compared to 314.5 minutes (IQR 204.0-459.3) for acute non-stroke transfers during the same period. Major themes of provider impressions included: incomplete awareness of the protocol, smooth process, challenges when a stroke alert was activated after EMS left the hospital, greater involvement of EMS in patient care, and comments on communication and efficiency. Conclusion: This pilot study demonstrated the feasibility, safety, and efficiency of a novel approach to expedite endovascular therapy for patients with LVOs.

Abstract WP42: FAST Implementation Of An Urban County Severity-based Stroke Triage Protocol: Impact And Outcomes On A Comprehensive Stroke Center

Background: Severity scales are recommended to assist field-based triage of acute stroke patients to designated stroke centers however require additional EMS education and performance. The Cincinnati prehospital stroke scale (CPSS) is a commonly used pre-hospital stroke screen and has been validated as a severity scale to identify large vessel occlusion (LVO). This study objective is to determine the impact of a county-based implementation of CPSS as a stroke severity scale to directly triage selected patients to a comprehensive stroke center (CSC). Methods: Dekalb County, Georgia in Atlanta implemented a CPSS-based triage protocol with a score of 3 and last seen normal (LSN) time < 24 hours mandating transfer to the nearest CSC if added time was <15 minutes. We compared patients presenting by EMS to the CSC six months before and after the protocol change (November 1, 2020) including frequencies of stroke alerts, diagnoses, LVO, IV tPA use, thrombectomy treatment and LSN time to treatment. Results: During the study period, 802 suspected acute stroke patients presented to the CSC by EMS including 95 (12%) with a FAST score of 3. There was a significant increase in monthly EMS stroke alerts with the protocol implementation (Pre- 43 ± 5.6, Post- 54 ± 5.9; p=0.005). Overall, 325 (41%) patients had a final diagnosis of stroke or TIA, including 228 (28%) with ischemic stroke. There was a significant increase in ischemic stroke patients presenting with LVO (Pre- 26%, Post- 36%; p=0.01) and the monthly rate of mechanical thrombectomy (Pre- 2.0 ± 2.0, Post- 5.5 ± 2.4; p= 0.005) but no difference in tPA administration rate. LSN to tPA median times were similar (Pre- 2.8 ± 1.1, Post- 2.6 ± 0.87 hours; p=0.66) though LSN to groin puncture median times increased (Pre- 3.2, Post- 7.1 hours; p=0.04). CPSS score of 3 was associated with the final diagnosis of ischemic stroke, IV tPA administration and presence of LVO (p=<0.001). Conclusion: County-based implementation of a CPSS score of 3 is a quick, easy and effective approach to triage suspected stroke patients to a thrombectomy-capable center that identifies stroke patients with LVO and increases thrombectomy treatment rates without delays in tPA treatment.

Bridging thrombolysis in atrial fibrillation stroke is associated with increased hemorrhagic complications without improved outcomes

BackgroundAtrial fibrillation (AF) associated ischemic stroke is associated with worse functional outcomes, less effective recanalization, and increased rates of hemorrhagic complications after intravenous thrombolysis (IVT). Conversely, AF is not associated...

Direct Transfer to Angiosuite in Acute Stroke

Time to reperfusion is one of the strongest predictors of functional outcome in acute stroke due to a large vessel occlusion (LVO). Direct transfer to angiography suite (DTAS) protocols have shown encouraging results in reducing in-hospital delays. DTAS allows bypassing of conventional imaging in the emergency room by ruling out an intracranial hemorrhage or a large established infarct with imaging performed before transfer to the thrombectomy-capable center in the angiography suite using flat-panel CT (FP-CT). The rate of patients with stroke code primarily admitted to a comprehensive stroke center with a large ischemic established lesion is <10% within 6 hours from onset and remains <20% among patients with LVO or transferred from a primary stroke center. At the same time, stroke severity is an acceptable predictor of LVO. Therefore, ideal DTAS candidates are patients admitted in the early window with severe symptoms. The main difference between protocols adopted in different centers is the inclusion of FP-CT angiography to confirm an LVO before femoral puncture. While some centers advocate for FP-CT angiography, others favor additional time saving by directly assessing the presence of LVO with an angiogram. The latter, however, leads to unnecessary arterial punctures in patients with no LVO (3%–22% depending on selection criteria). Independently of these different imaging protocols, DTAS has been shown to be effective and safe in improving in-hospital workflow, achieving a reduction of door-to-puncture time as low as 16 minutes without safety concerns. The impact of DTAS on long-term functional outcomes varies between published studies, and randomized controlled trials are warranted to examine the benefit of DTAS.

Abstract 1122‐000121: Integrated Geomapping Tool of Certified Stroke Centers in United States: A SVIN MT2020+ Committee Collaboration

Introduction : Stroke is a leading cause of morbidity, mortality and healthcare spending in the United States. Acute management of ischemic stroke is time‐dependent and evidence suggests improved clinical outcomes for patients treated at designated certified stroke centers. There is an increasing trend among hospitals to obtain certification as designated stroke centers. A common source or integrated tool providing both information and location of all available stroke centers in the US irrespective of the certifying organization is not readily available. The objective of our research is to generate a comprehensive and interactive electronic resource with combined data on all geographically‐coded certified stroke centers to assist in pre‐hospital triage and study healthcare disparities in stroke including availability and access to acute stroke care by location and population. Methods : Data on stroke center certification was primarily obtained from each of the three main certifying organizations: The Joint Commission (TJC), Det Norske Veritas (DNV) and Healthcare Facilities Accreditation Program (HFAP). Geographic mapping of all stroke center locations was performed using the ArcGIS Pro application. The most current data on stroke centers is presented in an interactive electronic format and the information is frequently updated to represent newly certified centers. Utility of the tool and its analytics are shown. Role of the tool in improving pre‐hospital triage in the stroke systems of care, studying healthcare disparities and implications for public health policy are discussed. Results : Aggregate data analysis at the time of submission revealed 1,806 total certified stroke centers. TJC‐certified stroke centers represent the majority with 106 Acute Stroke Ready (ASR), 1,040 Primary Stroke Centers (PSCs), 49 Thrombectomy Capable Centers (TSCs) and 197 Comprehensive Stroke Centers (CSCs). A total of 341 DNV‐certified programs including 36 ASRs, 162 PSCs, 16 PSC Plus (thrombectomy capable) and 127 CSCs were identified. HFAP‐certified centers (75) include 16 ASRs, 49 PSCs, 2 TSCs and 8 CSCs. A preliminary map of all TJC‐certified CSCs and TSCs is shown in the figure (1). Geospatial analysis reveals distinct areas with currently limited access to certified stroke centers and currently, access to certified stroke centers is extremely limited to non‐existent in fe States (for example: Idaho, Montana, Wyoming, New Mexico and South Dakota). Conclusions : Stroke treatment and clinical outcomes are time‐dependent and prompt assessment and triage by EMS directly to appropriate designated stroke centers is therefore critical. A readily available electronic platform providing location and treatment capability for all nearby certified centers will enhance regional stroke systems of care, including enabling more rapid inter‐hospital transfers for advanced intervention. Identifying geographic areas of limited access to treatment can also help improve policy and prioritize the creation of a more equitable and well‐distributed network of stroke care in the United States.

Distribution of Diagnoses and Clinical and Imaging Characteristics in 1,322 Consecutive Suspected Stroke Patients.

Background: Endovascular thrombectomy (EVT) has become the standard of care for large-vessel occlusion strokes, but several barriers for implementing an optimal organization of stroke management remain. Major issues include the lack of reliable data on the percentage of stroke patients potentially eligible for EVT especially in times of expanding indications for EVT. Our aim was therefore to study the frequencies of possible EVT-eligible patients such as patients with medium-vessel occlusions, patients with low Alberta Stroke Program Early Computed Tomography Scores (ASPECTS), patients presenting in an extended time window after onset of symptoms, and patients with mild symptoms at presentation (National Institutes of Health Stroke Scale, NIHSS ≤ 5). We also give detailed imaging and clinical information about the patients presenting with intracranial hemorrhage and other ischemic stroke mimics stratified by symptoms at presentation.Methods: Cohort study of all consecutive patients with suspected acute stroke presenting to a tertiary care center in Germany between September 1, 2016, and August 31, 2017. Baseline and follow-up clinical and imaging characteristics were collected from patients' medical charts.Results: Of 1,322 patients with a suspected acute stroke, 592 (44.8%) had ischemic strokes, 221 (16.7%) had hemorrhagic strokes, 190 (10.9%) had transient ischemic attacks (TIAs), and 319 (24.1%) were classified as stroke mimics. Stroke severity was mild (NIHSS ≤ 5) in 866 (65.5%) patients; 15.7% of the patients with an occlusion of the anterior circulation had an ASPECTS ≤ 5, 17.4% of the patients with an ischemic stroke had distal vessel occlusions, and 49% of the patients presented later than 6 h after onset of symptoms.Conclusion: Our results help to plan resources in thrombectomy-capable centers in times of expanding indications for EVT where resources will have to be adjusted to patients with low-NIHSS, low-ASPECTS, and distal occlusions, and patients presenting in the extended time window, which may altogether account for an additional 20% of all ischemic stroke patients.

Should Tenecteplase be Given in Clinical Practice for Acute Ischemic Stroke Thrombolysis?

Should Tenecteplase be Given in Clinical Practice for Acute Ischemic Stroke Thrombolysis?

Influence of Onset to Imaging Time on Radiological Thrombus Characteristics in Acute Ischemic Stroke.

Introduction: Radiological thrombus characteristics are associated with patient outcomes and treatment success after acute ischemic stroke. These characteristics could be expected to undergo time-dependent changes due to factors influencing thrombus architecture like blood stasis, clot contraction, and natural thrombolysis. We investigated whether stroke onset-to-imaging time was associated with thrombus length, perviousness, and density in the MR CLEAN Registry population.Methods: We included 245 patients with M1-segment occlusions and thin-slice baseline CT imaging from the MR CLEAN Registry, a nation-wide multicenter registry of patients who underwent endovascular treatment for acute ischemic stroke within 6.5 h of onset in the Netherlands. We used multivariable linear regression to investigate the effect of stroke onset-to-imaging time (per 5 min) on thrombus length (in mm), perviousness and density (both in Hounsfield Units). In the first model, we adjusted for age, sex, intravenous thrombolysis, antiplatelet use, and history of atrial fibrillation. In a second model, we additionally adjusted for observed vs. non-observed stroke onset, CT-angiography collateral score, direct presentation at a thrombectomy-capable center vs. transfer, and stroke etiology. We performed exploratory subgroup analyses for intravenous thrombolysis administration, observed vs. non-observed stroke onset, direct presentation vs. transfer, and stroke etiology.Results: Median stroke onset-to-imaging time was 83 (interquartile range 53–141) min. Onset to imaging time was not associated with thrombus length nor perviousness (β 0.002; 95% CI −0.004 to 0.007 and β −0.002; 95% CI −0.015 to 0.011 per 5 min, respectively) and was weakly associated with thrombus density in the fully adjusted model (adjusted β 0.100; 95% CI 0.005–0.196 HU per 5 min). The subgroup analyses showed no heterogeneity of these findings in any of the subgroups, except for a significantly positive relation between onset-to-imaging time and thrombus density in patients transferred from a primary stroke center (adjusted β 0.18; 95% CI 0.022–0.35).Conclusion: In our population of acute ischemic stroke patients, we found no clear association between onset-to-imaging time and radiological thrombus characteristics. This suggests that elapsed time from stroke onset plays a limited role in the interpretation of radiological thrombus characteristics and their effect on treatment results, at least in the early time window.

Direct mechanical thrombectomy without intravenous thrombolysis versus bridging therapy for acute ischemic stroke: A meta-analysis of randomized controlled trials.

Direct mechanical thrombectomy may result in similar outcomes compared to a bridging approach with intravenous thrombolysis (IVT + MT) in acute ischemic stroke. Recent randomized controlled trials have varied in their design and noninferiority margin. We sought to meta-analyze accumulated trial data to assess the difference and non-inferiority in clinical and procedural outcomes between direct mechanical thrombectomy and bridging therapy. We conducted a systematic review of electronic databases following the preferred reporting items for systematic reviews and meta-analyses guidelines. Random effects meta-analyses were conducted for the pooled data. The primary outcome was good functional outcome at 90 days (modified Rankin scale (mRS) ≤ 2). Secondary outcomes included excellent functional outcome (mRS ≤ 1), mortality, any intracranial hemorrhage, symptomatic intracranial hemorrhage, successful reperfusion (thrombolysis in cerebral infarction ≥ 2 b), and procedure-related complications. Four randomized controlled trials comprising 1633 patients (817 direct mechanical thrombectomy, 816 bridging therapy) were included. There were no statistical differences for the 90-day good functional outcome (OR = 1.02, 95% CI 0.84-1.25, p = 0.54, I2 = 0%), and the absolute risk difference was 1% (95% CI: -4% to 5%). The lower 95% CI falls within the strictest noninferiority margin of -10% among included randomized control trials. Direct mechanical thrombectomy reduced the odds of successful reperfusion (OR = 0.76, 95% CI: 0.60-0.97, p = 0.03, I2 = 0%) and any intracranial hemorrhage (OR = 0.65, 95% CI: 0.49-0.86, p = 0.003, I2 = 38%). There was no difference in the remaining secondary outcomes. The risk of bias for all studies was low. The combined trial data assessing direct mechanical thrombectomy versus bridging therapy showed no difference in improving good functional outcome. The wide noninferiority thresholds set by individual trials are in contrast with the clinical consensus on minimally important differences. However, our pooled analysis indicates noninferiority of direct mechanical thrombectomy with a 4% margin of confidence. The application of these findings is limited to patients presenting directly to mechanical thrombectomy-capable centers and real-world workflow times may differ against those achieved in a trial setting.

Telestroke Consultation in the Emergency Medical Services Unit: A Novel Approach to Improve Thrombolysis Times

BackgroundFaster treatment times are associated with improved outcomes in patients with acute ischemic stroke. In this prospective pilot study, we assess the feasibility of initiating telestroke consultation in emergency medical services unit (TEMS). MethodsPatients with stroke symptoms were evaluated via TEMS using a video-call with a stroke provider. After TEMS evaluation, patients were transferred to the nearest stroke center (NSC) or thrombectomy capable center (TCS) depending on stroke severity and symptom onset time. We compared time metrics between patients evaluated via TEMS to those via standard telestroke (STS) consultation. Results49 patients were evaluated via TEMS between May 2017 and March 2020. Median age was 66, 24 (49%) were females, 15 (30.6%) received intravenous alteplase (tPA) after arrival to a local hospital, and 3 (6.1%) underwent mechanical thrombectomy (MT) after bypassing the NSC. Compared to 52 tPA patients treated through STS consultation, TEMS patients had shorter door to needle (DTN) time (21 vs. 38 min, p < 0.001). In addition, patients who received MT after bypassing the NSC had shorter onset to groin time compared to those transferred from NSC (216 vs. 293 min, P = 0.04). ConclusionPrehospital stroke triaging using TEMS is feasible, and could result in shorter DTN and onset to groin times.

Abstract P20: Bridging Therapy Increases Hemorrhagic Complications Without Improving Functional Outcomes in Atrial Fibrillation Associated Stroke

* on behalf of the Stroke Thrombectomy and Aneurysm Registry (STAR) Collaborators Introduction: Intravenous thrombolysis complications are enriched in AF associated stroke, as these patients have worse functional outcomes, less effective recanalization, and increased rates of hemorrhagic complications. These data suggest that AF patients may be at particularly high risk for complications of bridging therapy for large vessel occlusions treated with mechanical thrombectomy (MT). Here we determine whether clinical outcomes differ in AF associated stroke treated with MT and bridging therapy. Methods: We performed a retrospective cohort study of the Stroke and Aneurysm Registry (STAR) from January 2015 to December 2018 and identified 4,169 patients who underwent MT for an anterior circulation stroke, 1,517 (36.4 %) of which had comorbid AF. Prospectively defined baseline characteristics and clinical outcomes were compared. Results: Hemorrhagic complications after MT were similar in patients with or without AF. In patients without AF, bridging therapy improved 90-day outcomes (aOR 1.32, 1.02-1.74, p&lt;0.05) without increasing hemorrhagic complications. In patients with AF, bridging therapy independently predicted hemorrhagic complications in AF patients (aOR 2.08, 1.06-4.06, p&lt;0.033) without improving functional outcomes. Conclusions: Bridging therapy in AF patients undergoing thrombectomy independently increased the odds of intracranial hemorrhage and did not improve functional outcomes. AF patients may represent a high-risk subgroup for thrombolytic complications. Randomized trials are warranted to determine whether patients with AF associated stroke may benefit by deferring bridging therapy at thrombectomy-capable centers.

Abstract P125: The First Year of Pre-Hospital Triage for Emergent Large Vessel Stroke Across a Large New York City Health System

Introduction: On April 1 2019, New York City EMS began a triage protocol using a modified Los Angeles Motor Scale (S-LAMS for addition of speech) to identify potential endovascular thrombectomy (EVT) eligible patients in the field (S-LAMS 4-6 with last known well (LKW) &lt;5 hours). These patients are routed to the nearest thrombectomy capable center, driving past potentially closer primary stroke centers. Methods: Patients brought by EMS to a large multicenter health system across NYC for the year following April 1, 2019 were extracted from a prospectively collected stroke database. S-LAMS triage positive (STP) patients were assessed for diagnostic accuracy and treatment times. They were compared with a cohort that underwent EVT during the same period, but triaged as S-LAMS triage negative (STN). Results: STP patients (N=145) were 56.6% women, mean age of 70, median baseline mRS of 0, S-LAMS score of 5, and arrival NIHSS of 13. Stroke was diagnosed in 110 (75.8%) patients, 32 intracerebral hemorrhage and 78 ischemic. Of the ischemic, 45 were large vessel occlusion stroke (ELVO) and 34 underwent EVT (PPV of 0.31 for ELVO). STN patients (N=65) with LKW of &lt; 5 hours were brought by EMS and underwent EVT; 34 were brought directly to EVT capable centers, and 36 required transfer for EVT. Mean time to hospital arrival from EMS scene arrival was significantly longer for STP patients than STN patients (38 vs. 29 minutes, p&lt;0.01). Mean ambulance travel time was significantly longer for STP patients than STN patients (10 vs. 7 minutes, p&lt;0.01). Mean tPA administration time from EMS scene arrival was not significantly different between STP (N=41) and STN patients (N=40) (90 vs. 91 minutes, p=0.89). Mean arterial access time for EVT from EMS scene arrival was significantly shorter for STP patients than STN patients (137 vs. 200 minutes, p&lt;0.01). Conclusions: Pre-hospital stroke triage using the streamlined S-LAMS scale is comparable with other pre-hospital scales in predictive value for ELVO. While pre-hospital evaluation and transport times are longer, they add minimal delay to the hospital arrival, do not affect tPA times, and improve times to EVT in a large, urban environment. Further analysis on effect of the triage protocol on patient outcomes is warranted.

Negative impact of Interhospital Transfer on Clinical Outcomes of Mechanical Thrombectomy for Fast Progressive Stroke

ObjectivesThe time-dependence of the clinical outcome of mechanical thrombectomy is higher in the “fast progressor” in whom cerebral ischemia progresses rapidly. The impact of time-consuming interhospital transfer (IT) on the clinical outcome of such patients is unknown. The effect on clinical outcomes of IT of fast progressors was investigated. MethodsAmong the patients enrolled in the Tokyo/Tama REgistry of Acute endovascular Thrombectomy, fast progressor cerebral ischemia cases were retrospectively investigated. In this study, a fast progressor was defined as a case with an Alberta Stroke Program Early CT Score less than 6 and last known well (LKW) to arterial puncture within 6 h. Patients’ background characteristics, treatment progress, and the modified Rankin Scale (mRS) score at 3 months were examined. ResultsOf a total of 1182 patients, 92 (7.8%) were included, with 76 patients in the direct transfer (DT) group, and 16 patients in the IT group. Median LKW to reperfusion was 190 min and 272 min, respectively (P<.001). The number of patients with mRS scores 0-2 at three months was 22 (28.9%) in the DT group and 1 (6.2%) in the IT group. Interhospital transfer was an independent factor associated with worse outcomes (odds ratio 0.08, 95% confidence interval 0.01-0.87, P=.038). ConclusionThis study showed that, among fast progressor patients, the IT group had a worse prognosis than the DT group. To provide good clinical outcomes for fast progressor patients, those who are likely to undergo mechanical thrombectomy should be sent directly to a thrombectomy-capable center.

Rapid Treatment of Acute Ischemic Stroke Using a Computed Tomography-Based Reperfusion Protocol: The Reality of a Local Community Hospital with Limited Resources.

In patients with acute ischemic stroke (AIS), prognosis strongly depends on the onset-to-recanalization time. The Ishinomaki protocol for rapid recanalization has been used since October 2017. This protocol determines the indication for reperfusion therapy based on computed tomography (CT)/three-dimensional CT angiography (3DCTA) findings and intends to reduce the onset-to-recanalization time. We aimed to compare the outcomes before and after protocol introduction. Our hospital is the only thrombectomy-capable center in Ishinomaki, Tome, and Kesennuma medical area. Before protocol introduction (April 2014-June 2016), both CT and magnetic resonance imaging were performed to determine the indications for intravenous (IV) recombinant tissue-plasminogen activator (rt-PA) or mechanical thrombectomy within 6 hours of disease onset. However, after protocol introduction (from October 2017), plain CT and 3DCTA were used. We collected data on patients who underwent mechanical thrombectomy and/or IV rt-PA before (n = 13) and after (n = 34) the protocol introduction. The required time from onset to door (OTD), door to needle (DTN), needle to puncture (NTP), puncture to recanalization (PTR), and door to recanalization (DTR) were compared before and after protocol introduction. Furthermore, thrombolysis in cerebral infarction (TICI) grades and modified Rankin scale (mRS) scores at discharge were compared. The outcomes before and after protocol introduction were as follows: OTD: 105 ± 73.8 (mean ± standard deviation) vs. 120 ± 68.1 min (p = 0.376, Mann-Whitney U test); DTN: 62.9 ± 15.9 vs. 41 ± 17 min (p <0.01); NTP: 112 ± 69.8 vs. 39.9 ± 33.7 min (p <0.01); PTR: 87.9 ± 45.4 vs. 52.5 ± 27.9 min (p <0.01); and DTR, 230 ± 69.9 vs. 110 ± 40.3 min (p <0.0001). Before and after protocol introduction, the proportion of patients with TICI grade 2b-3, mRS score of 0-2 at discharge, and mRS score of 5-6 were 54% vs. 50% (p = 0.815, Fisher's exact test), 23% vs. 21% (p = 0.854), and 15% vs. 50% (p = 0.046), respectively. The Ishinomaki protocol reduced the mean DTR time by 120 min. The reduction in treatment time was due to the change in CT-based recanalization and collaboration with emergency physicians and paramedics. There was no increase in good outcomes, but there was a significant increase in poor outcomes at discharge. Patients who could not be salvaged were indicated for reperfusion therapy as CT and 3DCTA cannot detect the ischemic core.