CT Perfusion collateral index in assessment of collaterals in acute ischemic stroke with delayed presentation: Comparison to single phase CTA.

BACKGROUND & PURPOSE: Perfusion collateral index (PCI) has been recently defined as a promising measure of collateral status. We sought to compare collateral status assessed via CT-PCI in comparison to single-phase CTA and their relationship to outcome measures including final infarction volume, final recanalization status and functional outcome in ELVO patients. METHODS: ELVO patients with anterior circulation large vessel occlusion who had baseline CTA and CT perfusion and underwent endovascular treatment were included. Collateral status was assessed on CTA. PCI from CT perfusion was calculated in each patient and an optimal threshold to separate good vs insufficient collaterals was identified using DSA as reference. The collateral status determined by CTA and PCI were assessed against 3 measured outcomes: 1) final infarction volume; 2) final recanalization status defined by TICI scores; 3) functional outcome measured by 90-day mRS. RESULTS: A total of 53 patients met inclusion criteria. Excellent recanalization defined by TICI ≥2C was achieved in 36 (68%) patients and 23 patients (43%) had good functional outcome (mRS ≤2). While having good collaterals on both CTA and CTP-PCI was associated with significantly (p<0.05) smaller final infarction volume, only good collaterals status determined by CTP-PCI was associated with achieving excellent recanalization (p = 0.001) and good functional outcome (p = 0.003). CONCLUSION: CTP-based PCI outperforms CTA collateral scores in determination of excellent recanalization and good functional outcome and may be a promising imaging marker of collateral status in patients with delayed presentation of AIS.

National Trends in Utilization and Outcome of Endovascular Thrombectomy for Acute Ischemic Stroke in Elderly.

OBJECTIVE: Octogenarians were excluded and/or underrepresented in the major endovascular thrombectomy (EVT) randomized controlled trials, but continue to make up a growing proportion of stroke patients. To evaluate real-world trends in utilization and outcome of EVT in patients ≥80 years in a large nationally representative database. METHODS: Using the Nationwide Inpatient Sample (2014-2016), we identified patients admitted to United States hospitals with acute ischemic stroke (AIS) who also underwent EVT. The primary endpoint was good outcome (discharge to home/acute rehabilitation center). Poor outcome (discharge to skilled nursing facility or hospice and in-hospital mortality), intracerebral hemorrhage and in-hospital mortality were secondary outcome measures. RESULTS: In 376,956 patients with AIS, 6,230(1.54%) underwent EVT. 1,547(24.83%) were ≥80. The rate of EVT in AIS patients ≥80 more than doubled from 0.83%(n = 317) in 2014 to 1.83%(n = 695) in 2016. The rate of good outcome in patients ≥80 was 9%, significantly lower than younger patients (26%, p<0.001). In-hospital mortality was 19% in patients ≥80 compared to 13% in the younger cohort (p < 0.001). There was no difference in the rate of hemorrhagic transformation between octogenarians and younger patients (18.52% vs 17.01%, p=0.19). In patients ≥80 years of age, decreasing baseline comorbidity burden independently predicted good outcome (OR 0.258, 95% CI [0.674- 0.935]). CONCLUSIONS: A two-fold increase in the utilization of EVT in patients ≥80 years of age was seen from 2014 to 2016. While the comparative rate of good outcome is significantly lower in this age group, elderly patients with fewer comorbidities demonstrated better outcomes after EVT.

Mobile Interventional Stroke Team Model Improves Early Outcomes in Large Vessel Occlusion Stroke: The NYC MIST Trial.

BACKGROUND AND PURPOSE: Triage of patients with emergent large vessel occlusion stroke to primary stroke centers followed by transfer to comprehensive stroke centers leads to increased time to endovascular therapy. A Mobile Interventional Stroke Team (MIST) provides an alternative model by transferring a MIST to a Thrombectomy Capable Stroke Center (TSC) to perform endovascular therapy. Our aim is to determine whether the MIST model is more time-efficient and leads to improved clinical outcomes compared with standard drip-and-ship (DS) and mothership models. METHODS: This is a prospective observational cohort study with 3-month follow-up between June 2016 and December 2018 at a multicenter health system, consisting of one comprehensive stroke center, 4 TSCs, and several primary stroke centers. A total of 228 of 373 patients received endovascular therapy via 1 of 4 models: mothership with patient presentation to a comprehensive stroke center, DS with patient transfer from primary stroke center or TSC to comprehensive stroke center, MIST with patient presentation to TSC and MIST transfer, or a combination of DS with patient transfer from primary stroke center to TSC and MIST. The prespecified primary end point was initial door-to-recanalization time and secondary end points measured additional time intervals and clinical outcomes at discharge and 3 months. RESULTS: MIST had a faster mean initial door-to-recanalization time than DS by 83 minutes (P<0.01). MIST and mothership had similar median door-to-recanalization times of 192 minutes and 179 minutes, respectively (P=0.83). A greater proportion had a complete recovery (National Institutes of Health Stroke Scale of 0 or 1) at discharge in MIST compared with DS (37.9% versus 16.7%; P<0.01). MIST had 52.8% of patients with modified Rankin Scale of ≤2 at 3 months compared with 38.9% in DS (P=0.10). CONCLUSIONS: MIST led to significantly faster initial door-to-recanalization times compared with DS, which was comparable to mothership. This decrease in time has translated into improved short-term outcomes and a trend towards improved long-term outcomes. Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT03048292.

Major Causes for Not Performing Endovascular Therapy Following Inter-Hospital Transfer in a Complex Urban Setting.

INTRODUCTION: Endovascular therapy (EVT) has emerged as the standard of care for emergent large vessel occlusion (ELVO) acute ischemic stroke. An increasing number of patients with suspected ELVO are being transferred to stroke centers with interventional capacity. Not all such inter-hospital transfers result in EVT. AIM: To identify the major causes for not performing EVT following transfer. METHODS: An analysis of 222 consecutive patients with suspected ELVO transferred for potential EVT between January 2015 and -December 2017 within a New York City health system was performed. About 36% (80/222) were deemed EVT ineligible and compared to an EVT cohort. RESULTS: Major causes for not performing EVT were established infarct (34%), no or recanalized ELVO (31%), and mild or clinically improved symptoms (21%). In the established infarct subgroup, 28% (7/27) arrived at a stroke center with interventional capacity within 5 h of last known well, compared to 61% (83/142) in the EVT cohort (p = 0.003). In the no or recanalized ELVO subgroup, 40% (10/25) received computed tomographic angiography at the primary stroke center (PSC), compared to 73% (104/142) in the EVT cohort (p = 0.001). Among patients treated with intravenous thrombolysis, 6% (6/104) improved from a NIHSS of ≥6 to <6 following transfer. CONCLUSIONS: Established infarct, no or recanalized ELVO, and mild or clinically improved symptoms were the major causes for not performing EVT for patients transferred for ELVO management. These may be addressed by decreasing stroke onset to treatment times and timely ELVO detection at the PSC and/or pre-hospital triage.

Acute Stroke Trial Enrollment through a Telemedicine Network: A 12-Year Experience.

BACKGROUND: A major barrier to acute stroke trial enrollment is timely access to participating centers. Establishing referral relationships via telemedicine may broaden trial access. We sought to understand the utilization of telemedicine in trial enrollment at a large academic center. METHODS: This is a single center, retrospective review of subjects consecutively enrolled into cerebrovascular trials requiring urgent consent between January 2005 and December 2016. Subjects were classified to either direct presentation to hub hospital, or transfer from spoke hospitals. We used Pearson linear correlation and a simple linear regression model to describe the relationship between annual trial enrollment rate and the number of spoke sites capable of audio-video evaluation (AVR) as a proxy for the size of the telemedicine network. We correlated the annual increase in enrollment with that of each group using parametric and nonparametric analysis. RESULTS: Sixteen trials met our criteria, enrolling 299 subjects: 117 in the hub group and 182 in the spoke group. There was a direct relationship between the number of AVR-capable sites and annual trial enrollment rate (P = <.05). Annual increase in spoke enrollment was higher compared to hub enrollment (15.55 ± 11.30 versus 0.68 ± 1.03, P <.0005) and better correlated with total increase in enrollments (0.98 versus 0.94, P <.0001). CONCLUSIONS: Telemedicine networks are a major resource for trial enrollment. Expanding the use of remote enrollment could expedite the completion of acute cerebrovascular trials.

Mobile Interventional Stroke Teams Lead to Faster Treatment Times for Thrombectomy in Large Vessel Occlusion.

BACKGROUND AND PURPOSE: Endovascular recanalization treatment for acute ischemic stroke is a complex, time-sensitive intervention. Trip-and-treat is an interhospital service delivery model that has not previously been evaluated in the literature and consists of a shared mobile interventional stroke team that travels to primary stroke centers to provide on-site interventional capability. We compared treatment times between the trip-and-treat model and the traditional drip-and-ship model. METHODS: We performed a retrospective analysis on 86 consecutive eligible patients with acute ischemic stroke secondary to large vessel occlusion who received endovascular treatment at 4 hospitals in Manhattan. Patients were divided into 2 cohorts: trip-and-treat (n=39) and drip-and-ship (n=47). The primary outcome was initial door-to-puncture time, defined as the time between arrival at any hospital and arterial puncture. We also recorded and analyzed the times of last known well, IV-tPA (intravenous tissue-type plasminogen activator) administration, transfer, and reperfusion. RESULTS: Mean initial door-to-puncture time was 143 minutes for trip-and-treat and 222 minutes for drip-and-ship (P<0.0001). Although there was a trend in longer puncture-to-recanalization times for trip-and-treat (P=0.0887), initial door-to-recanalization was nonetheless 79 minutes faster for trip-and-treat (P<0.0001). There was a trend in improved admission-to-discharge change in National Institutes of Health Stroke Scale for trip-and-treat compared with drip-and-ship (P=0.0704). CONCLUSIONS: Compared with drip-and-ship, the trip-and-treat model demonstrated shorter treatment times for endovascular therapy in our series. The trip-and-treat model offers a valid alternative to current interhospital stroke transfers in urban environments.

Novel and emerging technologies for endovascular thrombectomy.

Endovascular thrombectomy device improvements in recent years have served a pivotal role in improving the success and safety of the thrombectomy procedure. As the intervention gains widespread use, developers have focused on maximizing the reperfusion rates and reducing procedural complications associated with these devices. This has led to a boom in device development. This review will cover novel and emerging technologies developed for endovascular thrombectomy.

Time from image acquisition to endovascular team notification: a new target for enhancing acute stroke workflow.

OBJECTIVE: To quantify the time between initial image acquisition (CT angiography (CTA)) and notification of the neuroendovascular surgery (NES) team, a potentially high yield time window to target for optimization of endovascular thrombectomy (ET) treatment times. METHODS: We reviewed our multihospital database for all patients with a stroke with emergent large vessel occlusion treated with ET between January 1, 2017 and August 5, 2020. We dichotomized patients into rapid (≤20 min) and delayed (>20 min) notification times and analyzed treatment characteristics and outcomes. RESULTS: Of 367 patients with ELVO undergoing ET for whom notification data were available, the median time from CTA to NES team notification was 24 min (IQR 12-47). The median total treatment time was 180 min (IQR 129-252). The median times from CTA to NES team notification for rapid (n=163) and delayed (n=204) cohorts were 11 (IQR 6-15) and 43 (IQR 30-80) min, respectively (p<0.001). The median overall times to reperfusion were 134 min (IQR 103-179) and 213 min (IQR 172-291), respectively (p<0.001). The delayed patients had a significantly lower National Institutes of Health Stroke Scale (NIHSS) score on presentation (15 (IQR 9-20) vs 16 (IQR 11-22), p=0.03), were younger (70 (IQR 60-79) vs 77 (IQR 64-85), p<0.001), and more often presented with posterior circulation occlusion (16.7% vs 7.4%, p<0.01). The group with rapid notification time had a statistically larger median improvement in NIHSS score from admission to discharge (6 (IQR 0.5-14) vs 5 (IQR 0.5-10), p=0.04). CONCLUSIONS: Time delays from initial CTA acquisition to NES team notification can prevent expedient treatment with ET. Process improvements and automated stroke detection on imaging with automated notification of the NES team may ultimately improve time to reperfusion.

Middle Meningeal Artery Embolization for Chronic Subdural Hematoma Using N-Butyl Cyanoacrylate With D5W Push Technique.

BACKGROUND: Middle meningeal artery (MMA) embolization has been recognized as a promising treatment for patients with subdural hematoma (SDH). OBJECTIVE: To present the technical feasibility and efficacy of n-butyl cyanoacrylate (n-BCA) embolization in the largest consecutive cohort to date. METHODS: We retrospectively reviewed our consecutive cases of recurrent SDH treated with MMA embolization using diluted n-BCA with the "sugar rush" technique. In brief, a 2.1-Fr microcatheter was used to selectively catheterize the frontal and posterior branches of the MMA. 5% dextrose in water (D5W) was injected through an intermediate catheter while injecting n-BCA through the microcatheter. Complete obliteration of MMA and lack of SDH recurrence in a 3-6 months follow-up computed tomography scan were defined as efficacy outcomes. Cranial nerve palsy, vision loss, transient neurological deficit, and stroke were defined as safety outcomes. RESULTS: A total of 61 patients were identified with a mean (±standard deviation) age of 62.5 ± 9 years. In 6 patients (10%), coil embolization of the origin of the frontal or posterior branch was performed because super-selective catheterization of the branch was unsuccessful because of tortuous anatomy. Complete obliteration of frontal and posterior branches was achieved in 100% of the cases. Recurrent SDH was seen in 3 patients (5%). No incidence of cranial nerve palsy, vision loss, or stroke occurred. One patient suffered a transient neurological deficit. CONCLUSION: MMA embolization using diluted n-BCA with concomitant D5W injection is associated with a high degree of distal penetration and complete branch occlusion and minimal risk of cranial nerve palsy or other thromboembolic complications.

Bilateral middle cerebral artery occlusions treated with simultaneous bilateral thrombectomy: an approach to multivessel occlusions.

The scarcely described phenomenon of acute ischaemic stroke due to bilateral large vessel occlusions and limited reports of its treatment raises the question about the best method for revascularisation. We present a simultaneous bilateral thrombectomy method on a patient with acute bilateral middle cerebral artery occlusions. This technique resulted in successful vessel recanalisation within 35 min without haemorrhagic complications-deeming the method both safe and effective. Patient outcome was unfavourable, complicated by the patient's history of heart failure and other cardiac-related problems. Patient is residing at a skilled nursing facility with maximal assistance.

Artery of Percheron occlusion with first-pass recanalisation of the first segment of posterior cerebral artery.

This is an elderly patient who was found unconscious at home. CT of the head without contrast was unremarkable, while CT angiography of the head and neck revealed a subocclusive thrombus on the precommunicating (P1) segment of the left posterior cerebral artery (PCA). MRI brain revealed bilateral regions of diffusion restriction in the paramedian thalami and bilateral medial mesencephalon. Initial angiography confirmed the presence of a subocclusive thrombus in the P1 segment of the left PCA. Thrombectomy was performed achieving recanalisation of the left PCA and reperfusion of bilateral thalami via a visualised artery of Percheron. Postoperatively, the patient was kept on a daily dose of 325 mg of aspirin. The patient did not improve neurologically. A follow-up MRI brain showed diffusion restriction in the left occipital lobe and petechial haemorrhages in the bilateral thalami. The family eventually opted for palliative measures, and the patient expired on day 14 of admission due to acute respiratory failure from palliative extubating.

Stroke Code From EMS to Thrombectomy: An Interdisciplinary In Situ Simulation for Prompt Management of Acute Ischemic Stroke.

INTRODUCTION: Treatment of acute ischemic stroke is challenging because it requires prompt management, interdisciplinary collaboration, and adherence to specific guidelines. This resource addresses these challenges by providing in situ simulated practice with stroke codes by practicing clinicians at unannounced times. METHODS: An emergency department team was presented with a 55-year-old simulated patient with speech difficulty and right-sided weakness. The team had to assess her efficiently and appropriately, including activating the stroke team via the hospital paging system. The stroke team responded to collaboratively coordinate evaluation, obtain appropriate imaging, administer thrombolytic therapy, and recognize the need for thrombectomy. Learners moved through the actual steps in the real clinical environment, using real hospital equipment. Upon simulation completion, debriefing was utilized to review the case and team performance. Latent safety threats were recorded, if present. Participants completed an evaluation to gauge the simulation's effectiveness. RESULTS: Six simulations involving 40 total participants were conducted and debriefed across New York City Health + Hospitals. One hundred percent of teams correctly identified the presenting condition and assessed eligibility for thrombolytic and endovascular therapy. Evaluations indicated that 100% of learners found the simulation to be an effective clinical, teamwork, and communication teaching tool. Debriefing captured several latent safety threats, which were rectified by collaboration with hospital leadership. DISCUSSION: Impromptu, in situ simulation helps develop interdisciplinary teamwork and clinical knowledge and is useful for reviewing crucial times and processes required for best-practice patient care. It is particularly useful when timely management is essential, as with acute ischemic stroke.

Medical Management vs Mechanical Thrombectomy for Mild Strokes: An International Multicenter Study and Systematic Review and Meta-analysis.

Importance: The benefit of mechanical thrombectomy (MT) in patients with stroke presenting with mild deficits (National Institutes of Health Stroke Scale [NIHSS] score <6) owing to emergency large-vessel occlusion (ELVO) remains uncertain. Objective: To assess the outcomes of patients with mild-deficits ELVO (mELVO) treated with MT vs best medical management (bMM). Data Sources: We retrospectively pooled patients with mELVO during a 5-year period from 16 centers. A meta-analysis of studies reporting efficacy and safety outcomes with MT or bMM among patients with mELVO was also conducted. Data were analyzed between 2013 and 2017. Study Selection: We identified studies that enrolled patients with stroke (within 24 hours of symptom onset) with mELVO treated with MT or bMM. Main Outcomes and Measures: Efficacy outcomes included 3-month favorable functional outcome and 3-month functional independence that were defined as modified Rankin Scale scores of 0 to 1 and 0 to 2, respectively. Safety outcomes included 3-month mortality and symptomatic and asymptomatic intracranial hemorrhage (ICH). Results: We evaluated a total of 251 patients with mELVO who were treated with MT (n = 138; 65 women; mean age, 65.2 years; median NIHSS score, 4; interquartile range [IQR], 3-5) or bMM (n = 113; 51 women; mean age, 64.8; median NIHSS score, 3; interquartile range [IQR], 2-4). The rate of asymptomatic ICH was lower in bMM (4.6% vs 17.5%; P = .002), while the rate of 3-month FI (after imputation of missing follow-up evaluations) was lower in MT (77.4% vs 88.5%; P = .02). The 2 groups did not differ in any other efficacy or safety outcomes. In multivariable analyses, MT was associated with higher odds of asymptomatic ICH (odds ratio [OR], 11.07; 95% CI, 1.31-93.53; P = .03). In the meta-analysis of 4 studies (843 patients), MT was associated with higher odds of symptomatic ICH in unadjusted analyses (OR, 5.52; 95% CI, 1.91-15.49; P = .002; I2 = 0%). This association did not retain its significance in adjusted analyses including 2 studies (OR, 2.06; 95% CI, 0.49-8.63; P = .32; I2 = 0%). The meta-analysis did not document any other independent associations between treatment groups and safety or efficacy outcomes. Conclusions and Relevance: Our multicenter study coupled with the meta-analysis suggests similar outcomes of MT and bMM in patients with stroke with mELVO, but no conclusions about treatment effect can be made. The clinical equipoise can further be resolved by a randomized clinical trial.

Current advances in emergency department care of acute ischemic stroke: part 2: endovascular therapy

This review discusses the current evidence for endovascular therapy in the treatment of acute ischemic stroke and explores the indications for its use. Imaging studies and procedural techniques for endovascular therapy are also discussed.

Variant ascending pharyngeal artery maintaining flow in a subocclusive internal carotid artery.

Ectopic branches of the external carotid artery are rare but have critical diagnostic and therapeutic implications. We present a case involving a 70-year-old man who presented with recurrent left hemispheric strokes in the setting of a subocclusive left internal carotid stenosis. A left ascending pharyngeal artery with variant origin from the internal carotid artery helped maintain flow distal to the area of stenosis and allowed for safe and successful internal carotid artery stenting. Identification of this variant and recognition of the anastomotic network involving this connection were crucial to determine the safety of stenting. The patient had no further recurrent events and had sustained improvement on his 90-day follow-up.

Emerging Technologies in Optimizing Pre-Intervention Workflow for Acute Stroke.

Over the last several years, thrombectomy for large vessel occlusions (LVOs) has emerged as a standard of care for acute stroke patients. Furthermore, the time to reperfusion has been identified as a predictor of overall patient outcomes, and much effort has been made to identify potential areas to target in enhancing preintervention workflow. As medical technology and stroke devices improve, nearly all time points can be affected, from field stroke triage to automated imaging interpretation to mass mobile stroke code communications. In this article, we review the preintervention stroke workflow with specific regard to emerging technologies in improving time to reperfusion and overall patient outcomes.

Mechanical thrombectomy in pediatric stroke: systematic review, individual patient data meta-analysis, and case series.

OBJECTIVE: The role of mechanical thrombectomy in pediatric acute ischemic stroke is uncertain, despite extensive evidence of benefit in adults. The existing literature consists of several recent small single-arm cohort studies, as well as multiple prior small case series and case reports. Published reports of pediatric cases have increased markedly since 2015, after the publication of the positive trials in adults. The recent AHA/ASA Scientific Statement on this issue was informed predominantly by pre-2015 case reports and identified several knowledge gaps, including how young a child may undergo thrombectomy. A repeat systematic review and meta-analysis is warranted to help guide therapeutic decisions and address gaps in knowledge. METHODS: Using PRISMA-IPD guidelines, the authors performed a systematic review of the literature from 1999 to April 2019 and individual patient data meta-analysis, with 2 independent reviewers. An additional series of 3 cases in adolescent males from one of the authors' centers was also included. The primary outcomes were the rate of good long-term (mRS score 0-2 at final follow-up) and short-term (reduction in NIHSS score by ≥ 8 points or NIHSS score 0-1 at up to 24 hours post-thrombectomy) neurological outcomes following mechanical thrombectomy for acute ischemic stroke in patients < 18 years of age. The secondary outcome was the rate of successful angiographic recanalization (mTICI score 2b/3). RESULTS: The authors' review yielded 113 cases of mechanical thrombectomy in 110 pediatric patients. Although complete follow-up data are not available for all patients, 87 of 96 (90.6%) had good long-term neurological outcomes (mRS score 0-2), 55 of 79 (69.6%) had good short-term neurological outcomes, and 86 of 98 (87.8%) had successful angiographic recanalization (mTICI score 2b/3). Death occurred in 2 patients and symptomatic intracranial hemorrhage in 1 patient. Sixteen published thrombectomy cases were identified in children < 5 years of age. CONCLUSIONS: Mechanical thrombectomy may be considered for acute ischemic stroke due to large vessel occlusion (ICA terminus, M1, basilar artery) in patients aged 1-18 years (Level C evidence; Class IIb recommendation). The existing evidence base is likely affected by selection and publication bias. A prospective multinational registry is recommended as the next investigative step.

Endovascular thrombectomy in pediatric patients with large vessel occlusion.

BACKGROUND: Pediatric acute ischemic stroke with underlying large vessel occlusion is a rare disease with significant morbidity and mortality. There is a paucity of data about the safety and outcomes of endovascular thrombectomy in these cases, especially with modern devices. METHODS: We conducted a retrospective review of all pediatric stroke patients who underwent endovascular thrombectomy in nine US tertiary centers between 2008 and 2017. RESULTS: Nineteen patients (63.2% male) with a mean (SD) age of 10.9(6) years and weight 44.6 (30.8) kg were included. Mean (SD) NIH Stroke Scale (NIHSS) score at presentation was 13.9 (5.7). CT-based assessment was obtained in 88.2% of the patients and 58.8% of the patients had perfusion-based assessment. All procedures were performed via the transfemoral approach. The first-pass device was stentriever in 52.6% of cases and aspiration in 36.8%. Successful revascularization was achieved in 89.5% of the patients after a mean (SD) of 2.2 (1.5) passes, with a mean (SD) groin puncture to recanalization time of 48.7 (37.3) min (median 41.5). The mean (SD) reduction in NIHSS from admission to discharge was 10.2 (6.2). A good neurological outcome was achieved in 89.5% of the patients. One patient had post-revascularization seizure, but no other procedural complications or mortality occurred. CONCLUSIONS: Endovascular thrombectomy is safe and feasible in selected pediatric patients. Technical and neurological outcomes were comparable to adult literature with no safety concerns with the use of standard adult devices in patients as young as 18 months. This large series adds to the growing literature but further studies are warranted.

A review of acute ischemic stroke triage protocol evidence: a context for discussion.

Endovascular thrombectomy (EVT) is now the standard of care for eligible patients with acute ischemic stroke (AIS) secondary to emergent large vessel occlusion (ELVO). However, there remains uncertainty in how hospital systems can most efficiently route patients with suspected ELVO for EVT treatment. Given the relative geographic distribution of centers with and without endovascular capabilities, the value of prehospital triage directly to centers with the ability to provide EVT remains debated. While there are no randomized trial data available to date, there is substantial evidence in the literature that may offer guidance on the subject. In this review we examine the available data in the context of improving the existing AIS triage systems and discuss how prehospital triage directly to endovascular-capable centers may confer clinical benefits for patients with suspected ELVO.