Intrinsic hospital factors: overlooked cause for variations in delay to transfer for endovascular thrombectomy

BackgroundIntrinsic hospital factors leading to time delay to inter-hospital transfer for endovascular thrombectomy (EVT) have not been adequately investigated, leading to uncertainty in generalizability of hub and spoke EVT services. We investigated the contribution of intrinsic hospital factors to variations in time delay in a multicenter, retrospective study.MethodsThe setting was a hub and spoke EVT state-wide system for a population of 6.3 million and 34 spoke hospitals. We collected data on acute large vessel occlusion strokes transferred from spoke to hub for consideration of EVT between January 2016 and December 2018. The primary endpoint was the proportion of variability in delay-time in transfer cases contributed to by intrinsic hospital factors estimated through variance component analysis implemented as a mixed-effect linear regression model with hospitals as random effects.ResultsWe included 434 patients. The median age was 72 years (IQR 62–79), 44% were female, and the median baseline National Institutes of Health Stroke Scale (NIHSS) was 16 (IQR 11–20). The median onset to CT time was 100 mins (IQR 69–157) at the spoke hospitals and CT acquisition at the spoke hospital to time of transfer was 93 min (IQR 70–132). 53% of the observed variability in time from CT acquisition at the spoke hospital to transfer to the EVT center was explained by intrinsic hospital factors, as opposed to patient-related factors.ConclusionsIntrinsic hospital factors explained more than half of the observed variability in time from CT acquisition at the spoke hospital to departure for transfer. We recommend that the design of hub and spoke EVT services should account for intrinsic hospital factors to minimize hospital transfer delay.

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Abstract 1122‐000031: Reasons Thrombectomy Candidates Become Ineligible After Transfer for Treatment in a Hub‐And‐Spoke Telestroke Model

Stroke: Vascular and Interventional Neurology ◽

10.1161/svin.01.suppl_1.000031 ◽

2021 ◽

Vol 1 (S1) ◽

Author(s):

Robert W Regenhardt ◽

Amine Awad ◽

Andrew W Kraft ◽

Joseph A Rosenthal ◽

Adam A Dmytriw ◽

...

Keyword(s):

Arrival Time ◽

Functional Independence ◽

Long Term Outcomes ◽

Vessel Occlusion ◽

Hub And Spoke ◽

Hospital System ◽

Endovascular Thrombectomy ◽

Hospital Transfer ◽

Distal Occlusion

Introduction : The care of emergent large vessel occlusion (ELVO) stroke patients has been revolutionized by endovascular thrombectomy (EVT). Given its robust efficacy, it is crucial to optimize delivery to eligible patients. Within hub‐and‐spoke hospital system models, some patients first present to distant spoke hospitals and require transfer to hub hospitals for EVT. We sought to understand reasons EVT candidates become ineligible after transfer for treatment. Methods : Consecutive EVT candidates presenting to 25 spokes from 2018 to 2020 with pre‐transfer CTA‐defined ELVO and Alberta Stroke Program Early CT Score ≥6 were identified from a prospectively maintained database. Outcomes of interest included hub EVT, reasons for EVT ineligibility, and 90‐day functional independence (modified Rankin Scale, mRS ≤2). Results : 258 patients were identified with median age 70 years (IQR 60–81) and 50% female. 44% underwent EVT upon hub arrival, of which 87% achieved Thrombolysis in Cerebral Infarction 2b‐3 reperfusion. Compared to EVT‐eligible patients, ineligible patients were older (73 vs 68 years, p = 0.04), had lower NIH Stroke Scale (NIHSS, 10 vs 16, p<0.0001), longer LKW‐hub arrival time (8.4 vs 4.6 hours, p<0.0001), and received less IV alteplase (32% vs 45%, p = 0.04). The clinical reasons cited for becoming EVT ineligible upon hub arrival included large established infarct (49%), mild symptoms (33%), recanalization (6%), distal occlusion location (5%), subocclusive lesion (3%), and goals of care (3%). Becoming EVT ineligible independently reduced the odds of 90‐day functional independence (aOR = 0.26, 95%CI = 0.12,0.56; p = 0.001), even when controlling for age, NIHSS, and LKW‐hub arrival time. Conclusions : Approaches to increase EVT eligibility among ELVO transfers may improve long term outcomes. A primary reason for becoming EVT ineligible is infarct growth. Future studies should explore triaging patients directly to EVT‐capable hubs when feasible, improving inter‐hospital transfer times, supporting ischemic penumbra before EVT, and developing novel neuroprotective agents.

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Abstract WP280: A Potential Scoring System to Predict Infarct Progression During Inter Facility Transfer of Patients for Endovascular Thrombectomy Evaluation

Stroke ◽

10.1161/str.51.suppl_1.wp280 ◽

2020 ◽

Vol 51 (Suppl_1) ◽

Author(s):

Sujan Teegala Reddy ◽

Elliott Friedman ◽

Tzu-Ching Wu ◽

Xu Zhang ◽

Jing Zhang ◽

...

Keyword(s):

Systems Of Care ◽

Youden Index ◽

Coefficient Estimates ◽

Anterior Circulation ◽

Eligibility Criteria ◽

Vessel Occlusion ◽

Hub And Spoke ◽

Endovascular Thrombectomy ◽

Stroke Systems Of Care ◽

Current Guidelines

Introduction: Current guidelines recommend CT ASPECTS≥6 as eligibility criteria for endovascular thrombectomy (EVT), a proven therapy for anterior circulation large vessel occlusion (ACLVO). Infarct progression during inter-facility transfer can render many patients ineligible for EVT. We developed a score utilizing clinical and imaging variables to predict infarct progression. Methods: Patients with ACLVO transferred from a referring hospital (RH) to our EVT capable center between August 2015 and December 2018 were reviewed. Significant predictors (p<0.10) of infarct progression, defined as CT ASPECTS of ≥6 at RH to <6 at hub, were identified using a logistic regression model. Regression coefficient estimates were used to score selected variables. The optimal cut-point was selected based on evaluated Youden index. Results: A total of 132 patients were analyzed. Score ranged from 0 to theoretical limit 18 (table 1): CTA collateral score (2/3/4=0, 0/1=3), Clot location (not ICA/M2=0, M2=2, ICA/M1=3), NIHSS (0-14=0, ≥15=5), use of antiplatelet by history (Yes=0, No=3), CT ASPECTS at RH (10=0, 6-9=2). Patients with score of ≥10.0 were more likely to have infarct progression (OR=22.15, 95% CI 4.99 - 98.35, p<0.001). Conclusions: Our score utilizing clinical and imaging variables provides information on which patients with ACLVO may undergo infarct progression during inter-facility transfer. We plan to externally validate our findings in another hub and spoke network. This score may potentially aid decisions to develop stroke systems of care to triage patients with ACLVO within hub and spoke networks.

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Thrombectomy for acute ischemic stroke in nonagenarians compared with octogenarians

Journal of NeuroInterventional Surgery ◽

10.1136/neurintsurg-2019-015147 ◽

2019 ◽

Vol 12 (3) ◽

pp. 266-270 ◽

Cited By ~ 7

Author(s):

Eric S Sussman ◽

Blake Martin ◽

Michael Mlynash ◽

Michael P Marks ◽

David Marcellus ◽

...

Keyword(s):

Ischemic Stroke ◽

Acute Ischemic Stroke ◽

Functional Independence ◽

Inclusion Criteria ◽

Related Factors ◽

Vessel Occlusion ◽

Endovascular Thrombectomy ◽

Improved Outcomes ◽

Symptomatic Intracranial Hemorrhage ◽

The Difference

IntroductionMultiple randomized trials have shown that endovascular thrombectomy (EVT) leads to improved outcomes in acute ischemic stroke (AIS) due to large vessel occlusion (LVO). Elderly patients were poorly represented in these trials, and the efficacy of EVT in nonagenarian patients remains uncertain.MethodsWe performed a retrospective cohort study at a single center. Inclusion criteria were: age 80–99, LVO, core infarct <70 mL, and salvageable penumbra. Patients were stratified into octogenarian (80–89) and nonagenarian (90–99) cohorts. The primary outcome was the ordinal score on the modified Rankin Scale (mRS) at 90 days. Secondary outcomes included dichotomized functional outcome (mRS ≤2 vs mRS ≥3), successful revascularization, symptomatic intracranial hemorrhage (ICH), and mortality.Results108 patients met the inclusion criteria, including 79 octogenarians (73%) and 29 nonagenarians (27%). Nonagenarians were more likely to be female (86% vs 58%; p<0.01); there were no other differences between groups in terms of demographics, medical comorbidities, or treatment characteristics. Successful revascularization (TICI 2b–3) was achieved in 79% in both cohorts. Median mRS at 90 days was 5 in octogenarians and 6 in nonagenarians (p=0.09). Functional independence (mRS ≤2) at 90 days was achieved in 12.5% and 19.7% of nonagenarians and octogenarians, respectively (p=0.54). Symptomatic ICH occurred in 21.4% and 6.4% (p=0.03), and 90-day mortality rate was 63% and 40.9% (p=0.07) in nonagenarians and octogenarians, respectively.ConclusionsNonagenarians may be at higher risk of symptomatic ICH than octogenarians, despite similar stroke- and treatment-related factors. While there was a trend towards higher mortality and worse functional outcomes in nonagenarians, the difference was not statistically significant in this relatively small retrospective study.

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'Drip-and-ship' intravenous thrombolysis and outcomes for large vessel occlusion thrombectomy candidates in a hub-and-spoke telestroke model

Journal of NeuroInterventional Surgery ◽

10.1136/neurintsurg-2021-017819 ◽

2021 ◽

pp. neurintsurg-2021-017819

Author(s):

Robert W Regenhardt ◽

Joseph A Rosenthal ◽

Amine Awad ◽

Juan Carlos Martinez-Gutierrez ◽

Neal M Nolan ◽

...

Keyword(s):

Intravenous Thrombolysis ◽

Functional Independence ◽

Large Vessel ◽

Large Vessel Occlusion ◽

Vessel Occlusion ◽

Hub And Spoke ◽

Endovascular Thrombectomy ◽

Increased Risk ◽

Intravenous Alteplase ◽

Model Versus

BackgroundRandomized trials have not demonstrated benefit from intravenous thrombolysis among patients undergoing endovascular thrombectomy (EVT). However, these trials included primarily patients presenting directly to an EVT capable hub center. We sought to study outcomes for EVT candidates who presented to spoke hospitals and were subsequently transferred for EVT consideration, comparing those administered alteplase at spokes (i.e., ‘drip-and-ship’ model) versus those not.MethodsConsecutive EVT candidates presenting to 25 spokes from 2018 to 2020 with pre-transfer CT angiography defined emergent large vessel occlusion and Alberta Stroke Program CT score ≥6 were identified from a prospectively maintained Telestroke database. Outcomes of interest included adequate reperfusion (Thrombolysis in Cerebral Infarction (TICI) 2b–3), intracerebral hemorrhage (ICH), discharge functional independence (modified Rankin Scale (mRS) ≤2), and 90 day functional independence.ResultsAmong 258 patients, median age was 70 years (IQR 60–81), median National Institutes of Health Stroke Scale (NIHSS) score was 13 (6-19), and 50% were women. Ninety-eight (38%) were treated with alteplase at spokes and 113 (44%) underwent EVT at the hub. Spoke alteplase use independently increased the odds of discharge mRS ≤2 (adjusted OR 2.43, 95% CI 1.08 to 5.46, p=0.03) and 90 day mRS ≤2 (adjusted OR 3.45, 95% CI 1.65 to 7.22, p=0.001), even when controlling for last known well, NIHSS, and EVT; it was not associated with an increased risk of ICH (OR 1.04, 95% CI 0.39 to 2.78, p=0.94), and there was a trend toward association with greater TICI 2b–3 (OR 3.59, 95% CI 0.94 to 13.70, p=0.06).ConclusionsIntravenous alteplase at spoke hospitals may improve discharge and 90 day mRS and should not be withheld from EVT eligible patients who first present at alteplase capable spoke hospitals that do not perform EVT. Additional studies are warranted to confirm and further explore these benefits.

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Abstract WP278: Air versus Ground Transportation During Inter-Hospital Transfer of Patients for Endovascular Thrombectomy Evaluation

Stroke ◽

10.1161/str.51.suppl_1.wp278 ◽

2020 ◽

Vol 51 (Suppl_1) ◽

Author(s):

Sujan Teegala Reddy ◽

Tzu-Ching Wu ◽

Xu Zhang ◽

Farhaan Vahidy ◽

Christy Ankrom ◽

...

Keyword(s):

Air Transport ◽

Large Vessel Occlusion ◽

Vessel Occlusion ◽

Endovascular Thrombectomy ◽

Hospital Transfer ◽

The Difference ◽

Ground Distance ◽

Mode Of Transport ◽

Positive Results ◽

Iv Tpa

Introduction: Mode of transport utilized during inter-hospital transfers can influence delays in patients with suspected large vessel occlusion (LVO). We hypothesized that air transport is advantageous over ground in this patient population. Method: Suspected LVO patients transferred to our hub from 13 spoke hospitals within our tele-stroke network at UT-Houston, from September 2015 to April 2018 were retrospectively analyzed. Patients were dichotomized into air vs. ground transport. Travel time was calculated as time from transfer center activation to arrival at hub. For each spoke, average air miles/hour and ground miles/hour indices were calculated for comparison. Air transport was considered advantageous if the difference in indices was positive. Results were stratified by time of the day [diurnal (6a-6p) vs. nocturnal (6p-6a)]. Results: In a total of 339 patients, 290 (86%) used air transport, while 49 (14%) used ground. Baseline age, gender, race, use of IV-tPA, mRS in the 2 groups were similar, except air group had higher NIHSS [median 15 vs. 12, p = 0.048]. Overall, mean ground indices were smaller compared to air indices (21.35 ± 10.76 vs. 25.77 ± 14.33, p = 0.006). The advantage of air transport was maintained when stratified by time of the day but more notable during nocturnal hours [air 25.12 ± 14.93 vs. ground 19.85 ± 10.14, p = 0.021)] compared to diurnal hours [(air 28.82 ± 13.68 vs. ground 25.00 ± 10.80, p = 0.17)]. Difference between air and ground indices (y axis) was positively correlated with ground distance (x axis) (Pearson rho = 0.80, 95% CI 0.42 to 0.93, p<0.001) indicating efficiency of air transport becomes more profound as distance increases (Figure 1). Ground transport was faster for distances <20 miles. Conclusion: Irrespective of time of the day, air transport is faster mode of transporting patients during inter hospital transfers and should be utilized particularly for spokes situated farther away (over 20 miles) from hub and during nocturnal hours.

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Early detection of large‐vessel occlusion stroke after cardiac surgery using CT angiography leading to early recanalization with endovascular thrombectomy

Clinical Case Reports ◽

10.1002/ccr3.4246 ◽

2021 ◽

Vol 9 (5) ◽

Author(s):

Kiyoshi Takemoto ◽

Masaaki Sakuraya ◽

Michitaka Nakamura ◽

Hidetsugu Maekawa ◽

Kazuo Yamanaka ◽

...

Keyword(s):

Cardiac Surgery ◽

Early Detection ◽

Ct Angiography ◽

Large Vessel ◽

Large Vessel Occlusion ◽

Vessel Occlusion ◽

Endovascular Thrombectomy

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Endovascular thrombectomy time metrics in the era of COVID-19: observations from the Society of Vascular and Interventional Neurology Multicenter Collaboration

Journal of NeuroInterventional Surgery ◽

10.1136/neurintsurg-2020-017205 ◽

2021 ◽

pp. neurintsurg-2020-017205

Author(s):

Alexandra L Czap ◽

Alicia M Zha ◽

Jacob Sebaugh ◽

Ameer E Hassan ◽

Julie G Shulman ◽

...

Keyword(s):

Care Delivery ◽

Control Period ◽

Secondary Analysis ◽

Primary Analysis ◽

Vessel Occlusion ◽

Endovascular Thrombectomy ◽

Final Multivariable Model ◽

Multivariable Regression ◽

Multi Center Study ◽

Multivariable Adjustment

BackgroundUnprecedented workflow shifts during the coronavirus disease 2019 (COVID-19) pandemic have contributed to delays in acute care delivery, but whether it adversely affected endovascular thrombectomy metrics in acute large vessel occlusion (LVO) is unknown.MethodsWe performed a retrospective review of observational data from 14 comprehensive stroke centers in nine US states with acute LVO. EVT metrics were compared between March to July 2019 against March to July 2020 (primary analysis), and between state-specific pre-peak and peak COVID-19 months (secondary analysis), with multivariable adjustment.ResultsOf the 1364 patients included in the primary analysis (51% female, median NIHSS 14 [IQR 7–21], and 74% of whom underwent EVT), there was no difference in the primary outcome of door-to-puncture (DTP) time between the 2019 control period and the COVID-19 period (median 71 vs 67 min, P=0.10). After adjustment for variables associated with faster DTP, and clustering by site, there remained a trend toward shorter DTP during the pandemic (βadj=-73.2, 95% CI −153.8–7.4, Pp=0.07). There was no difference in DTP times according to local COVID-19 peaks vs pre-peak months in unadjusted or adjusted multivariable regression (βadj=-3.85, 95% CI −36.9–29.2, P=0.80). In this final multivariable model (secondary analysis), faster DTP times were significantly associated with transfer from an outside institution (βadj=-46.44, 95% CI −62.8 to – -30.0, P<0.01) and higher NIHSS (βadj=-2.15, 95% CI −4.2to – -0.1, P=0.05).ConclusionsIn this multi-center study, there was no delay in EVT among patients treated for intracranial occlusion during the COVID-19 era compared with the pre-COVID era.

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Differences in Acute Ischemic Stroke Management and Prognosis between Multiple Large-Vessel Occlusion and Single Large-Vessel Occlusion: Subanalysis of the RESCUE-Japan Registry 2

Cerebrovascular Diseases ◽

10.1159/000514369 ◽

2021 ◽

Vol 50 (4) ◽

pp. 397-404

Author(s):

Kotaro Tatebayashi ◽

Kazutaka Uchida ◽

Hiroto Kageyama ◽

Hirotoshi Imamura ◽

Nobuyuki Ohara ◽

...

Keyword(s):

Ischemic Stroke ◽

Acute Ischemic Stroke ◽

Patient Characteristics ◽

Large Vessel ◽

Large Vessel Occlusion ◽

Vessel Occlusion ◽

Endovascular Thrombectomy ◽

Tandem Occlusion ◽

The Mean ◽

Patient Prognosis

Introduction: The management and prognosis of acute ischemic stroke due to multiple large-vessel occlusion (LVO) (MLVO) are not well scrutinized. We therefore aimed to elucidate the differences in patient characteristics and prognosis of MLVO and single LVO (SLVO). Methods: The Recovery by Endovascular Salvage for Cerebral Ultra-Acute Embolism Japan Registry 2 (RESCUE-Japan Registry 2) enrolled 2,420 consecutive patients with acute LVO who were admitted within 24 h of onset. We compared patient prognosis between MLVO and SLVO in the favorable outcome, defined as a modified Rankin Scale (mRS) score ≤2, and in mortality at 90 days by adjusting for confounders. Additionally, we stratified MLVO patients into tandem occlusion and different territories, according to the occlusion site information and also examined their characteristics. Results: Among the 2,399 patients registered, 124 (5.2%) had MLVO. Although there was no difference between the 2 groups in terms of hypertension as a risk factor, the mean arterial pressure on admission was significantly higher in MLVO (115 vs. 107 mm Hg, p = 0.004). MLVO in different territories was more likely to be cardioembolic (42.1 vs. 10.4%, p = 0.0002), while MLVO in tandem occlusion was more likely to be atherothrombotic (39.5 vs. 81.3%, p < 0.0001). Among MLVO, tandem occlusion had a significantly longer onset-to-door time than different territories (200 vs. 95 min, p = 0.02); accordingly, the tissue plasminogen activator administration was significantly less in tandem occlusion (22.4 vs. 47.9%, p = 0.003). However, interestingly, the endovascular thrombectomy (EVT) was performed significantly more in tandem occlusion (63.2 vs. 41.7%; adjusted odds ratio [aOR], 2.3; 95% confidence interval [CI], 1.1–5.0). The type of MLVO was the only and significant factor associated with EVT performance in multivariate analysis. The favorable outcomes were obtained less in MLVO than in SLVO (28.2 vs. 37.1%; aOR, 0.48; 95% CI, 0.30–0.76). The mortality rate was not significantly different between MLVO and SLVO (8.9 vs. 11.1%, p = 0.42). Discussion/Conclusion: The prognosis of MLVO was significantly worse than that of SLVO. In different territories, we might be able to consider more aggressive EVT interventions.

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Penumbra Consumption Rates Based on Time-to-Maximum Delay and Reperfusion Status: A Post Hoc Analysis of the DEFUSE 3 Trial

Stroke ◽

10.1161/strokeaha.120.033806 ◽

2021 ◽

Author(s):

Shadi Yaghi ◽

Eytan Raz ◽

Seena Dehkharghani ◽

Howard Riina ◽

Ryan McTaggart ◽

...

Keyword(s):

Ischemic Stroke ◽

Infarct Volume ◽

Interquartile Range ◽

Large Vessel ◽

Large Vessel Occlusion ◽

Vessel Occlusion ◽

Endovascular Thrombectomy ◽

Post Hoc Analysis ◽

Consumption Rates ◽

Post Hoc

Background and Purpose: In patients with acute large vessel occlusion, the natural history of penumbral tissue based on perfusion time-to-maximum (T max ) delay is not well established in relation to late-window endovascular thrombectomy. In this study, we sought to evaluate penumbra consumption rates for T max delays in patients with large vessel occlusion evaluated between 6 and 16 hours from last known normal. Methods: This is a post hoc analysis of the DEFUSE 3 trial (The Endovascular Therapy Following Imaging Evaluation for Ischemic Stroke), which included patients with an acute ischemic stroke due to anterior circulation occlusion within 6 to 16 hours of last known normal. The primary outcome is percentage penumbra consumption, defined as (24-hour magnetic resonance imaging infarct volume–baseline core infarct volume)/(T max 6 or 10 s volume–baseline core volume). We stratified the cohort into 4 categories based on treatment modality and Thrombolysis in Cerebral Infarction (TICI score; untreated, TICI 0-2a, TICI 2b, and TICI3) and calculated penumbral consumption rates in each category. Results: We included 141 patients, among whom 68 were untreated. In the untreated versus TICI 3 patients, a median (interquartile range) of 53.7% (21.2%–87.7%) versus 5.3% (1.1%–14.6%) of penumbral tissue was consumed based on T max >6 s ( P <0.001). In the same comparison for T max >10 s, we saw a difference of 165.4% (interquartile range, 56.1%–479.8%) versus 25.7% (interquartile range, 3.2%–72.1%; P <0.001). Significant differences were not demonstrated between untreated and TICI 0-2a patients for penumbral consumption based on T max >6 s ( P =0.52) or T max >10 s ( P =0.92). Conclusions: Among extended window endovascular thrombectomy patients, T max >10-s mismatch volume may comprise large volumes of salvageable tissue, whereas nearly half the T max >6-s mismatch volume may remain viable in untreated patients at 24 hours.

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