Thrombectomy-capable Centers Research Articles

Interfacility Transfer for Thrombectomy: A Promising Therapeutic Window.

Currently, most acute ischemic stroke patients presenting with a large vessel occlusion are first evaluated at a nonthrombectomy-capable center before transfer to a comprehensive stroke center that performs thrombectomy. Interfacility transfer is a complex process that requires extensive coordination between the referring, transporting, and receiving facilities. As a result, long delays are common, contributing to poor clinical outcomes. In this review, we summarize the accumulating literature about the clinical as well as radiological-infarct growth, collateral change, arterial recanalization, and hemorrhagic transformation-changes during interfacility transfer for thrombectomy. Recent evidence shows that clinical/radiological changes during transfer are heterogeneous across patients and impact long-term functional outcomes, highlighting the urgent need to optimize care during this time window. We review some of the most promising therapeutic strategies-for example, penumbral protection to reduce infarct growth-that may improve clinical outcome in patients being transferred to thrombectomy-capable centers. Finally, we discuss key methodological considerations for designing clinical trials aimed at reducing infarct growth during transfer.

Outcomes of different anesthesia techniques in nonagenarians treated with mechanical thrombectomy for anterior circulation large vessel occlusion: An inverse probability weighting analysis.

There is a lack of evidence for the optimal type of anesthesia technique in patients ⩾ 90 years with acute ischemic stroke undergoing mechanical thrombectomy (MT) as this subgroup of patients was often excluded or under-represented in previous trials. We aimed to compare outcomes between general anesthesia (GA) and non-GA techniques in patients ⩾ 90 years with large vessel occlusion (LVO) undergoing MT. Our study included patients ⩾ 90 years with anterior circulation LVO, NIHSS ⩾ 6, ASPECTS ⩾ 5 consecutively treated with MT within 6 h after stroke onset in three thrombectomy capable centers between January 1st, 2016 and March 30th, 2023. Inverse probability weighting (IPW) was used to reduce bias by indication of the anesthesia type on study outcomes. We used a weighted ordinal robust logistic regression analysis to explore the primary outcome of modified Rankin Scale (mRS) shift at 90 days in GA versus non-GA treated patients. Secondary outcomes included 90-day mortality, symptomatic intracranial hemorrhage (sICH) and TICI score of 2b, 2c, or 3. We included 139 patients ⩾ 90 years treated with MT, 62 were in GA group and 77 in non-GA group. There was a significant shift for worse mRS scores at 90-day in non-GA treated patients (cOR 3.65, 95% CI 1.77-7.77, p = 0.001). The weighted logistic regression showed that non-GA technique was an independent predictor of 90-day mortality (OR 7.49, 95% CI 2.00-28.09; p = 0.003). Our study indicated that nonagenarians with acute ischemic stroke treated with MT without GA have a worse prognosis than their counterparts undergoing MT with GA. Further studies in larger cohorts are warranted to evaluate the optimal type of anesthesia in this patient population.

"Chopperlysis": The effect of helicopter transport on reperfusion and outcomes in large vessel occlusion strokes.

In large vessel occlusion (LVO) stroke patients transferred to a comprehensive stroke center for thrombectomy, spontaneous reperfusion may occur during transport, and anecdotally more frequently in patients transferred via helicopter than by ground. This pattern has been more often observed in conjunction with tenecteplase (TNK) treatment prior to helicopter transport. We aim to explore the "chopperlysis" effect-how helicopter transport, particularly with thrombolytics, may affect reperfusion and clinical outcomes. A single thrombectomy capable center (TCC) registry of stroke patients was retrospectively reviewed. Included LVO patients were those who had been transferred to the TCC and received a digital subtraction angiography (DSA) upon arrival. The outcomes were rates of spontaneous reperfusion, distal clot migration, and 90-day good functional outcome. Data were summarized, and endpoints were compared between patients stratified by transport method and/or TNK treatment. Of 270 patients included, helicopter transport was associated with a higher rate of spontaneous reperfusion, particularly among patients not treated with TNK (p < 0.001). There was no significant difference in prevalence of distal clot migration between any subgroups (p > 0.37). Overall, TNK-treated patients had better functional outcomes, and this difference persisted exclusively in the helicopter-transported patients (p = 0.02). Helicopter transport was associated with a higher rate of spontaneous reperfusion. There is a potentially synergistic effect between TNK administration and helicopter transport, augmenting thrombolysis and improving long-term outcomes. Further analyses in larger cohorts may expand our understanding of this "chopperlysis" effect.

Efficacy and Safety of Intravenous Tenecteplase Before Endovascular Thrombectomy for Acute Ischemic Stroke: The Multicenter, Randomized, BRIDGE-TNK Trial Protocol.

Six randomized trials have not detected a difference between intravenous alteplase plus endovascular thrombectomy and endovascular thrombectomy alone in stroke. Tenecteplase, a recombinant human tenecteplase tissue-type plasminogen activator, is a genetically modified variant of alteplase. It is unclear whether the outcomes are different if alteplase is replaced with tenecteplase. This trial aims to determine whether intravenous tenecteplase within 4.5 hours of time last known well confers benefit in patients with acute ischemic stroke with large-vessel occlusion who undergo endovascular thrombectomy. BRIDGE-TNK (Thrombectomy With Versus Without rhTNK-tPA in Stroke) is an investigator-initiated, multicenter, prospective, randomized, open-label trial with blinded end point evaluation conducted at 40 thrombectomy-capable centers in China. This trial will randomize 544 patients with intravenous thrombolysis-eligible stroke (272 in each arm) with large-vessel occlusion within 4.5 hours of last known well to receive bridging intravenous tenecteplase with endovascular thrombectomy (tenecteplase-plus-thrombectomy group) or endovascular thrombectomy alone (thrombectomy-alone group). The primary outcome is the proportion of patients achieving functional independence, defined as a score of 0 to 2 on the modified Rankin Scale, at 90 days. Safety will be assessed via symptomatic intracranial hemorrhage at 48 hours and death at 90 days. BRIDGE-TNK will provide important data on the role of intravenous tenecteplase before endovascular thrombectomy in patients with acute ischemic stroke with large-vessel occlusion who can be treated within 4.5 hours of last known well. URL: https://clinicaltrials.gov. Unique identifier: NCT04733742.

Navigating stroke care: Geospatial assessment of regional stroke center accessibility: Geospatial Assessment of Stroke Centers

IntroductionReducing time between stroke onset and hospital intervention is crucial for positive outcomes in stroke patients. While EMS utilization decreases time to intervention, many US regions are not within timely proximity to an advanced-care-capable stroke center (ASC), defined as a comprehensive or thrombectomy-capable center. This study aims to utilize geographic methodology to identify regions in Wisconsin with both high stroke mortality and low physical accessibility to certified stroke centers (SCs), particularly ASCs. MethodsGeocoded mortality records for stroke death between 2015 and 2020 were accessed from the Wisconsin Department of Health Services. Indirectly age-standardized mortality ratios (SMRs) were estimated continuously across Wisconsin using adaptive spatial filtering and mortality records at the census block group level; the surface was then averaged by census tract for tract level SMRs. Addresses for SC locations within Wisconsin and bordering states were collected, and drive times from Wisconsin census tract centroids to the nearest SC subtypes were estimated. Drive times and mortality ratios were evaluated at the tract level alongside Rural-Urban Commuting Area (RUCA) codes. Spatial error regression modeling was used to determine RUCA classifications with the highest stroke risk independent of accessibility to stroke centers. ResultsApproximately 50%, 68%, and 78% of Wisconsin residents resided within 30, 45, and 60 minutes of an ASC, respectively. Median drive time from census tract centroids to the nearest ASC were highest for rural tracts (M=90 minutes, IQR=68-115) compared to small-town (M=82 minutes, IQR=49-113), micropolitan (M=53 minutes, IQR=43-77), and metropolitan tracts (M=19 minutes, IQR=11-35; p<0.001). Clusters of high stroke SMRs were found in urban centers as well as rural areas irrespective of county declinations. Spatial regression modeling suggested small-town census tracts had the highest SMR irrespective of physical accessibility to care and spatial correlation. In small-town census tracts >45 minutes from the nearest ASC, the median stroke SMR was 1.12 (IQR=0.94-1.40) with 226,000 residents and 150 stroke deaths per year. ConclusionSmall-town areas are associated with both long drive distance to ASC locations and high stroke mortality. Geographical analyses reveal apparent stroke care deserts and may inform strategic allocation of emergency medicine resources and coverage.

Upfront vascular imaging in acute stroke: Impact on thrombectomy transfer time at a primary stroke center

ObjectivesEarly cerebral arterial imaging is currently only recommended in the subgroup of acute ischemic stroke (AIS) patients suspected of having large vessel occlusion (LVO). There is limited data on the impact of early cerebrovascular imaging in all suspected AIS patients presenting within 24 h of symptom onset and the impact on door in-door out (DIDO) time. Materials and methodsIn January 2020, our Primary Stroke Center implemented a protocol to perform upfront head and neck CT angiography (CTA) with initial non-contrast CT head for all suspected ischemic stroke patients screening positive for BE-FAST stroke symptoms within 24 h from last known normal time. We retrospectively reviewed IV alteplase and thrombectomy-eligible patients before (January 1-December 31, 2019) and after protocol implementation (January 1, 2020-June 30, 2022). ResultsOf 86 patients meeting study criteria, up-front CTA was associated with significant reductions in door-to-CTA start (median 37 vs 15 min, p = 0.003), door-to-CTA result (median 83 vs 52 min, p = 0.023) and DIDO times (median 150 vs 106 min, p = 0.023). There was no significant difference in door-to-needle time before and after protocol implementation (median 48 vs 43 min, p = 0.450). ConclusionUp-front cerebrovascular imaging with CTA in suspected AIS patients presenting within 24 h resulted in shorter DIDO times without delaying door-to-needle times. Primary Stroke Centers should consider this approach to detect LVO early and expedite patient transport to thrombectomy capable centers.

Predictors of futile recanalization in nonagenarians treated with mechanical thrombectomy: a multi-center observational study

BackgroundThere is a lack of data regarding patients aged 90 years or older undergoing mechanical thrombectomy and their predictors of futile recanalization.AimsWe sought to evaluate the predictors of futile recanalization in patients ≥ 90 years with large vessel occlusion undergoing mechanical thrombectomy.MethodsThis multi-center observational retrospective study included patients ≥ 90 years consecutively treated with mechanical thrombectomy in four thrombectomy capable centers between January 1st, 2016 and 30th March 2023. Futile recanalization was defined as large vessel occlusion patients experiencing a 90-day poor outcome (mRS 3–6) despite successful recanalization (mTICI ≥ 2b) after mechanical thrombectomy.ResultsOur cohort included 139 patients ≥ 90 years with acute ischemic stroke due to anterior circulation large vessel occlusion treated with mechanical thrombectomy. One hundred seventeen of one hundred thirty-nine patients ≥ 90 years who achieved successful recanalization were included in the analysis (seventy-six female (64.9%)), of whom thirty-one (26.49%) experienced effective recanalization and eighty-six (73.51%) experienced futile recanalization. Patients with futile recanalization had higher NIHSS on admission (p < 0.001); they were less frequently treated with intravenous thrombolysis (p = 0.048), had more often general anesthesia (p = 0.011), and longer door to groin puncture delay (p = 0.002). Univariable regression analysis showed that use of intravenous thrombolysis (0.29, 95% CI 0.02–0.79, p = 0.034) and site of occlusion distal vs proximal (0.34, 95% CI 0.11–0.97, p = 0.044) were associated with reduced probability of futile recanalization while NIHSS on admission (1.29, 95% CI 1.16–1.45, p < 0.001), NIHSS at 24 h (1.15, 95% CI 1.07–1.25, p = 0.002), type of anesthesia used (4.18, 95% CI 1.57–11.08, p = 0.004), and door to groin puncture time (1.02, 95% CI 1.00–1.05, p = 0.005) were associated with increased probability of futile recanalization. Multivariable regression analysis showed that use of intravenous thrombolysis (0.44, 95% CI 0.09–0.88, p = 0.039) was associated with reduced probability of futile recanalization.ConclusionOur study seems to suggest that mechanical thrombectomy with intravenous thrombolysis is associated with reduced probability of futile recanalization in a multi-center cohort of patients aged 90 years or older.

Impact of Direct Transport to Thrombectomy-Capable Center vs. Nearby/Distant Local Stroke Centers on Stroke Outcome in Patients Undergoing Thrombectomy: A Real-Life Study.

Our aim was to compare the stroke outcomes of a direct transfer (DT) to a thrombectomy-capable center vs. initial care at two local stroke centers: a nearby hospital (NH, 36 km) and a distant hospital (DH, 113 km). Patients who underwent a mechanical thrombectomy were analyzed (February 2017-October 2021), and the outcome was considered favorable if the modified Rankin scale (mRS) score was ≤ 2 at three months. A total of 300 patients were included, 55 of which were transferred from the NH and 58 from the DH. There was a difference in the median (IQR) transfer time of 39 min between the hospitals (149 min for the NH vs. 188 min for the DH, p = 0.003). After adjusting for confounding variables, a secondary transfer from the DH, compared to a DT, was associated with a lower functional independence: mRS score ≤ 2 (OR = 0.37, 95% CI = 0.14-0.97, p = 0.043), without significant differences in the mortality between the groups. These differences were not observed in patients from the NH. Conclusions: A secondary transfer from a distant hospital was associated with a poorer functional outcome at 3 months. This unfavorable outcome was not observed among patients transferred from a nearby hospital. These findings highlight the importance of categorizing the suitability of one transfer model over another based on the proximity of hospitals to the thrombectomy center, but also in accordance with organizational and geographic characteristics that vary within each health region.

Stroke interhospital nursing transport to thrombectomy capable center

Stroke interhospital nursing transport to thrombectomy capable center

Abstract WMP50: Disparities of Interhospital Transfer for Mechanical Thrombectomy in Acute Stroke in US

Introduction: A large proportion of mechanical thrombectomies (MT) in acute stroke include patients transferred from an outside hospital to thrombectomy capable centers. However, patient characteristics associated with the odds of transfer is unknown. We explored the US national claims database to explore predictors of interfacility transfer in MT hospitalizations using a nationally representative sample. Methods: National Inpatient Sample database was retrospectively explored from 2016 to 2020 for stroke hospitalizations with EVT. The primary outcome was transfer status from the presenting emergency department of MT-capable hospital. Multivariable logistic regression models with multiple robustness checks were performed to determine patient characteristics with the odds of transfer. Results: This study included 100,865 patients with MT, of whom 32,685 patients (32.4%) were transferred (median [IQR] age, 71 [60-81] years; 16775 women [51.2%]; 23090 White individuals [74.9%]; 3715 Black individuals [12.1%]; 1875 Hispanic individuals [6.1%]; 895 Asian individuals [2.9%]). White race, higher baseline NIHSS, hospital size and status (urban teaching vs rural), and hospital location were independent predictors of interfacility transfer for MT. Conclusion: Nearly one in 3 MTs in the US is performed in patients presenting following transfer from another acute care hospital. Analysis of population level data utilizing the National Inpatient Sample database shows disparities in the transfer of patients with minority backgrounds (Black, Hispanic, Asian) for MT. Urban teaching centers, larger hospitals, higher baseline NIHSS, and hospital location (northeast and midwest) were more likely to receive Interhospital MT transfers regardless of race.

Abstract TP193: Impact of Number of Passes on Outcomes of Mechanical Thrombectomy in Stroke Patients With Low ASPECTS

Introduction: Real-world data showed that less than half of the acute ischemic stroke (AIS) patients with large vessel occlusion (LVO) presenting with low Alberta Stroke Program Early Computed Tomography Score (ASPECTS) (2-5) achieved favorable outcomes at 90 days after mechanical thrombectomy (MT). In this study, we aim to investigate the relationship between the number of MT passes at which successful recanalization is obtained and outcomes in LVO-related AIS patients with low ASPECTS. Methods: This retrospective cohort study was performed on the data from 31 thrombectomy-capable centers between 2013 to 2022. Successful recanalization was defined as modified Thrombolysis in Cerebral Ischemia Score≥ 2b. The primary outcome was a 90-day modified Rankin Scale (mRS) of 0-3. Secondary outcomes were symptomatic intracranial hemorrhage and intracranial hemorrhage within 24 hours and mortality at 90 days. Outcomes were compared among patients with unsuccessful recanalization, and successful recanalization at first, second, third, and more than four passes. Results: A total of 297 patients with a median age of 70 [IQR 59-78] years were included and 140 (47.1%) were female. In 239 (80.4%) patients, successful recanalization was achieved: 88 patients (29.6 %) with 1 pass, 59 patients (19.9 %) with 2 passes, 35 patients(11.8%) with 3 passes, and 57 patients (19.2%) with more than 4 passes. Compared to unsuccessful recanalization, successful recanalization at first pass (adjusted OR 5.25, 95% CI 1.78 - 17.1), second passes (adjusted OR 5.20, 95% CI 1.68 - 17.6), and passes 4 (adjusted OR 4.90, 95% CI 1.68 - 17.6) was related to 90-day mRS 0-3. Recanalization status and MT attempt number were not related to secondary outcomes except for 90-day mortality. Compared to unsuccessful recanalization, successful recanalization at second and third passes were inversely related to 90-day mortality (adjusted OR 0.37, 95% CI 0.14 - 0.93; adjusted OR 0.33, 95% CI 0.11 - 0.95, respectively). Conclusion: The present results indicated that successful recanalization was related to 90-day good outcome regardless of the number of MT passes but the odds of achieving favorable outcome declines with each pass.

Comparison of Mothership Versus Drip‐and‐Ship Models for Endovascular Treatment of Basilar Artery Occlusion in the London Metropolitan Area

Background To date it is uncertain whether the drip‐and‐ship (DS) model (transport to the nearest primary stroke centers) or the mothership (MS) model (direct transportation to the comprehensive stroke center) is the best prehospital stroke system of care to deliver endovascular thrombectomy in patients with basilar artery occlusion. In the present analysis, we aim to investigate the impact of MS versus DS model in patients with basilar artery occlusion treated with endovascular thrombectomy in the London metropolitan area. Methods This is a multicenter observational, investigator‐initiated, retrospective study comparing outcomes (functional independence, defined as modified Rankin scale scores of 0 through 2, the rate of successful reperfusion, and the rate of complications postprocedure) in DS versus MS stroke patients with basilar artery occlusion admitted in 5 thrombectomy capable centers in London (United Kingdom). Results Of 113 patients, 38 (33.6%) patients were MS and 75 (66.4%) were DS. Between the 2 groups we did not observe statistically significant differences for most of the clinical characteristics. There was a significant difference regarding the rate of functional independence at 3 months between the MS and DS groups, respectively 47.4% versus 36% ( P = 0.047). Rates of complications postprocedure and successful recanalization did not differ between the 2 groups. Multivariable regression analysis demonstrated that MS model was an independent predictor of functional independence at 90 days (odds ratio [OR] 1.17; [95% CI, 1.11–1.26]; P = 0.003 and independent negative predictor of postoperative complications (OR, 0.39; [95% CI, 0.16–0.98]; P = 0.045). Conclusion Our study showed that MS model was a predictor of functional independence at 3 months and reduced risk of postoperative complications post‐endovascular thrombectomy in patients with basilar artery occlusion in a metropolitan area.

Performance of RAPID noncontrast CT stroke platform in large vessel occlusion and intracranial hemorrhage detection.

Noncontrast CT (NCCT) is used to evaluate for intracerebral hemorrhage (ICH) and ischemia in acute ischemic stroke (AIS). Large vessel occlusions (LVOs) are a major cause of AIS, but challenging to detect on NCCT. The purpose of this study is to evaluate an AI software called RAPID NCCT Stroke (RAPID, iSchemaView, Menlo Park, CA) for ICH and LVO detection compared to expert readers. In this IRB approved retrospective, multicenter study, stand-alone performance of the software was assessed based on the consensus of 3 neuroradiologists and sensitivity and specificity were determined. The platform's performance was then compared to interpretation by readers comprised of eight general radiologists (GR) and three neuroradiologists (NR) in detecting ICH and hyperdense vessel sign (HVS) indicating LVO. A total of 244 cases were included. Of the 244, 115 were LVOs and 26 were ICHs. One hundred three cases did not have LVO nor ICH. Stand-alone performance of the software demonstrated sensitivities and specificities of 96.2 and 99.5% for ICH and 63.5 and 95.1% for LVO detection. Compared to all 11 readers and eight GR readers only respectively, the software demonstrated superiority, achieving significantly higher sensitivities (63.5% versus 43.6%, p < 0.0001 and 63.5% versus 40.9%, p = 0.001). The RAPID NCCT Stroke platform demonstrates superior performance to radiologists for detecting LVO from a NCCT. Use of this software platform could lead to earlier LVO detection and expedited transfer of these patients to a thrombectomy capable center.

Differential thrombectomy utilization across hospital classifications in the United States

ObjectivesTo determine hospital-level factors associated with thrombectomy uptake. Materials and methodsThe Nationwide Emergency Department Sample was retrospectively queried to determine the total number of thrombectomies performed based on different hospital characteristics. Joint point analysis was used to determine which years were associated with significant increases in the number of high-volume thrombectomy centers (ostensibly defined as >50 thrombectomies/year), thrombectomy-capable centers (>15 thrombectomies/year), and total number of thrombectomies performed. Multivariable logistic regression was used to determine hospital factors associated with having an increased odds of performing thrombectomies, and of being classified as a high-volume thrombectomy or a thrombectomy-capable center. ResultsBetween 2007-2020 there was a stepwise increase in the number of thrombectomy-capable and high-volume thrombectomy centers in the United States. In 2020, there were a total of 15,705 thrombectomies performed, with 89 high-volume thrombectomy centers, and 359 thrombectomy-capable centers. The number of thrombectomy-capable centers significantly increased after 2011. After 2013 and 2016 there was a significant change in the growth rate of high-volume thrombectomy centers. There was also a significant increase in the total number of thrombectomies performed after 2016. Hospital characteristics that were associated with an increased likelihood of being classified as thrombectomy-capable or high-volume included trauma level 1 and 2 hospitals. ConclusionsBetween 2007 and 2020, there was a marked growth in thrombectomy utilization for acute ischemic stroke. This growth outpaced new diagnoses of ischemic stroke, and was driven largely by certain hospital types, with the greatest rises following seminal publications of positive randomized thrombectomy trials.

Influence of vascular imaging acquisition at local stroke centers on workflows in the drip-n-ship model: a RACECAT post hoc analysis

BackgroundThe influence of vascular imaging acquisition on workflows at local stroke centers (LSCs) not capable of performing thrombectomy in patients with a suspected large vessel occlusion (LVO) stroke remains uncertain....

Mission thrombectomy 2020 (MT2020+) surveys of Caribbean stroke services: A call for action in our region

Stroke is the leading cause of death and adult-onset disability in the Caribbean region. Despite the tremendous advances in acute stroke care in the past 25 years, treatment in the Caribbean lags stroke standards of care. Mission Thrombectomy 2020+ (MT2020+) is a metrics based global campaign focused on increasing access to organized stroke care and mechanical thrombectomy.We conducted two consecutive online surveys across the MT2020+ Caribbean Region assessing access to thrombolytics, mechanical thrombectomy and stroke centers. The first survey - Mechanical Thrombectomy Access-Caribbean sub-study, allowed a comparison between global services and those in the MT2020+ Caribbean region. This survey provided a snapshot of the current state of stroke centers worldwide and confirmed lower available stroke resources in the MT2020+ Caribbean Region which has one certified stroke center, and 9 mechanical thrombectomy capable centers. The second survey - MT2020+ Caribbean Region infrastructure survey - was designed to determine the availability of stroke resources that are key components of stroke care in participating hospitals. Key infrastructural components such as 24/7 computerized tomographic scanners, access to thrombolytic therapy and access to mechanical thrombectomy capable centers were scarce. There were low volumes of mechanical thrombectomy performed in the Caribbean compared to other countries around the world.Limited resources and inadequate stroke infrastructure remains a major challenge in the Caribbean. We advocate for governmental support and investment, public and private partnerships and legislation to increase access and availability to acute stroke treatments to allow for equal access to care for all Caribbean citizens.

Abstract TP76: Lost To Follow Up As A Missed Opportunity In ICH Survivors

Introduction: Improving rates of in-hospital survival in intracerebral hemorrhage (ICH) have led to opportunities to implement secondary prevention and recovery measures. Lost to follow up is not well characterized in this disabled population. The objective of this analysis was to describe the frequency of lost to follow up for ICH survivors from an urban comprehensive stroke center and thrombectomy capable center. Methods: We included n=409 ICH patients from December 2016 to February 2022. With chart review, we collected data regarding the admission, discharge and follow-up. Our primary outcome measure was a modified Rankin scale (mRS) score of 0 - 3 during their last recorded follow-up. Pearson correlation analyses were performed using R statistical software to determine if there was a significant correlation between the number of follow-ups a patient received and their final recorded mRS score. Results: Of 409 ICH patients, 80 died within the first month of their index hospitalization or had incomplete records that prevented further analysis. Of the 329 patients, 181 were minorities (83 blacks, 49 asian and 49 hispanics) and 90 were white. About 85% (279/329) had insurance. Only 162 received 3 or more follow-ups post-index hospitalization, with 47 patients never receiving any follow-ups after their initial discharge. Of those that received follow up, the average number of follow ups was 2.57, with an average time of 366.17 days between discharge and the last recorded follow-up. Among the 282 patients that received at least one follow-up, there was a significant negative correlation between the number of follow-ups a patient received and their final recorded mRS score (p = 0.0000339, r = -0.246). There was no significant differences related to age, race or insurance status for those who followed up versus those who were lost to follow up. Conclusions: In a large urban health system, 14% ICH survivors were lost to follow-up. ICH survivors with good functional outcomes received more follow-up. There is a need to improve systems of care to prevent ICH patients from getting lost to follow-up and improving long term outcomes.

Abstract WP25: Up-front Vascular Imaging At A Primary Stroke Center: Impact On Door In Door Out Time For Patients With Acute Ischemic Stroke And Large Vessel Occlusion

Background: AHA/ASA guidelines recommend obtaining early vessel imaging with CT angiography (CTA) or MR angiography (MRA) only in a select group of acute ischemic stroke (AIS) patients suspected to have large vessel occlusion (LVO). There is limited data on the utility of early cerebrovascular imaging in all suspected AIS patients presenting within 24 hours and its impact on door in-door out (DIDO) time. Methods: In January 2020, our Primary Stroke Center implemented a protocol to obtain upfront head and neck CTA simultaneously with a non contrast head CT for all suspected ischemic stroke patients screening positive for BE-FAST stroke symptoms within 24 hours from last known normal time. We retrospectively reviewed patients before (January 1-December 31, 2019) and after protocol implementation (January 1, 2020-June 30, 2022) to assess time metrics for patients receiving IV thrombolysis and/or transfer for thrombectomy. Results: A total of 86 AIS patients were evaluated during the study period. Time metrics before and after protocol implementation for thrombectomy eligible patients are shown in the figure. Compared to 2019, up-front CTA was associated with significant reductions in Door-to-CTA start (median 37 vs 14 minutes, p=0.05), Door-to-CTA interpretation (median 83 vs 52 minutes, p=0.02) and DIDO times (median 150 vs 106 minutes, p=0.02) in the final 12 months of the study period. There was no significant difference in door-to-needle time before and after protocol implementation (median 48 vs 43 minutes, p=0.40). Conclusion: In conclusion, up-front cerebrovascular imaging with CTA in suspected AIS patients presenting within 24 hours resulted in shorter DIDO times without delaying door-to-needle times. Primary Stroke Centers should consider this approach to detect LVO early and accelerate patient transport to thrombectomy capable centers.

Abstract WP4: Intravenous Thrombolysis And Outcomes In Patients With Large-vessel Stroke Directly Admitted Or Transferred To A Thrombectomy-capable Center

Objective: To assess whether the effect of intravenous thrombolysis in patients with large-vessel occlusion differed between patients directly admitted to thrombectomy-capable centers and patients transferred from local stroke centers without thrombectomy capabilities. Methods: We included 3206 patients with an acute ischemic large-vessel stroke with first imaging within 7 hours after onset that were directly admitted to thrombectomy-capable centers and treated with thrombectomy, or transferred from local stroke centers for thrombectomy evaluation, between 2017 and 2021 in Catalonia, Spain. Primary outcome was the degree of disability at 90 days, as evaluated by the shift analysis on the mRs score. Secondary outcomes included mortality at 90 days and the rate of parenchymal hemorrhage and successful reperfusion. Inverse-probability weighting clustered at the type of stroke center was used to estimate the effects. Results: The analysis included 2268 patients (975[49%] treated with thrombolysis) directly admitted to thrombectomy-capable centers and 938 patients (580[66%] treated with thrombolysis and 616[67%] treated with thrombectomy) transferred from local stroke centers (mean age 72±13 years, median NIHSS score 17[IQR 12-21], 1363 female[48%]). Patients treated with intravenous thrombolysis were younger, had shorter time from onset to first image acquisition, and higher rates of wake-up stroke, atrial fibrillation and anticoagulation intake. The effect of intravenous thrombolysis on the primary outcome was similar in patients directly admitted to thrombectomy-capable centers (acOR 1.50, 95% CI 1.24-1.81) and patients transferred from local stroke centers (acOR 1.44, 95% CI 1.04 to 2.01)(p interaction =0.68). Patients treated with intravenous thrombolysis had lower mortality rate, higher rate of parenchymal hematoma and similar rate of successful reperfusion, with no difference according to type of center (p interaction &gt;0.1). Conclusion: Administration of intravenous thrombolysis in patients with a large-vessel stroke with intention to thrombectomy was associated with higher odds of good functional outcome and higher rates of parenchymal hematoma, independently of the type of stroke center were it was administered.

CT after interhospital transfer in acute ischemic stroke: Imaging findings and impact of prior intravenous contrast administration.

Large vessel occlusion (LVO) stroke patients routinely undergo interhospital transfer to endovascular thrombectomy capable centers. Imaging is often repeated with residual intravenous (IV) iodine contrast at post-transfer assessment. We determined imaging findings and the impact of residual contrast on secondary imaging. Anterior circulation LVO stroke patients were selected out of a consecutive cohort. Directly admitted patients were contrast naïve, and transferred patients had previously received IV iodine contrast for stroke assessment at the referring hospital. Two independent readers rated the visibility of residual contrast on non-contrast computed tomography (CT) after transfer and assessed the hyperdense vessel sign. Multivariate linear regression analysis was used to investigate the association of the Alberta Stroke Program Early CT score (ASPECTS) with prior contrast administration, time from symptom onset (TFSO), and CTP ischemic core volume in both directly admitted and transferred patients. We included 161 patients, with 62 (39%) transferred and 99 (62%) directly admitted patients. Compared between these groups, transferred patients had a longer TFSO-to-imaging at our institution (median: 212 vs. 75 min, p < 0.001) and lower ASPECTS (median: 8 vs. 9, p < 0.001). Regression analysis presented an independent association of ASPECTS with prior contrast administration (β = -0.25, p = 0.004) but not with TFSO (β = -0.03, p = 0.65). Intergroup comparison between transferred and directly admitted patients pointed toward a stronger association between ASPECTS and CTP ischemic core volume in transferred patients (β = -0.39 vs. β = -0.58, p = 0.06). Detectability of the hyperdense vessel sign was substantially lower after transfer (66 vs. 10%, p < 0.001). Imaging alterations due to residual IV contrast are frequent in clinical practice and render the hyperdense vessel sign largely indetectable. Larger studies are needed to clarify the influence on the association between ASPECTS and ischemic core.