Emergency Endovascular Therapy Research Articles

Effect of abnormal distribution of abdominal adiposity and skeletal muscle on the outcomes of endovascular treatment for emergent large vessel occlusion

BackgroundThe aim of this study was to investigate the relationships between imaging indicators of obesity, as measured by computed tomography (CT), and clinical outcomes at 90 days and 1 year...

Factors associated with unfavorable outcome of anterior circulation ischemic stroke following emergency endovascular therapy after complete recanalization

Objective: Endovascular thrombectomy (EVT) improves long-term patients outcomes and decreases mortality among ischemic stroke patients. However, not all patients can benefit from EVT recanalization. The present study aims to evaluate the predictors of unfavorable outcomes associated with emergency endovascular therapy despite complete recanalization. Methods: We investigated 74 eligible patients receiving EVT from January 2019 to January 2022 at a comprehensive stroke center. Demographics, clinical, radiological and treatment characteristics, safety, and functional outcomes were collected. Modified Rankin scale (mRS) score ≤ 2 at 90 days was defined as a good functional outcome. Results: A total of 111 patients were initially eligible for the study, of which 37 were excluded, resulting in 74 patients in the final study. The mean age was 69.08±12.12 years old, 67.57% patients were male, 44.59% patients with atrial fibrillation, 64.86% with hypertension, 21.62% patients with diabetes mellitus, 16.22% patients with coronary artery diseases, 6.76% with parenchymal hematoma. Median pre-EVT NIHSS (IQR) was 15.5 (12.0, 19.25). Median door-to-recanalization time (DRT) (IQR) was 208.0 (160.0,278.5) minutes and median last known norma to puncture time (LKNPT) (IQR), was 362.0 (280, 452.5) minutes. Individuals with a poorer outcome were older [73.56±9.29 vs. 65.28±13.02 years old, P=0.002], had a higher prevalence of atrial fibrillation (AF) [58.82 vs. 13%, P=0.023] and a higher National Institute of Health Stroke Scale (NIHSS) [median 16 (IQR 12.0-22.3) vs median 15 (IQR 10.0-18.0), P=0.143]. Female sex, hypertension, diabetes mellitus, coronary artery disease, and a slightly longer door-to-recanalization time were more prevalent in the unfavorable prognosis group; however, statistical analysis did not show any significant differences. Logistics binary regression model showed that older age [OR: 0.1.160 (1.011 to 1.112, P=0.031)] and AF [OR: 3.190 (1.111 to 9.164, P=0.031)] were associated with an unfavorable outcome. Conclusion: Older age, and atrial fibrillation were factors associated with the unfavorable outcome despite complete recanalization after emergency EVT of ischemic stroke.

The impact of artificial intelligence on large vessel occlusion stroke detection and management: A systematic review meta-analysis

IntroductionStroke remains the second leading cause of death worldwide, with many survivors facing significant disabilities. In acute stroke care, the timeless adage 'Time is brain' underscores the vital need for quick action. Innovative Artificial Intelligence (AI) technology potentially enables swift detection and management of acute ischemic strokes, revolutionizing acute stroke care towards enhanced automation. MethodsThe study is registered with Prospero under CRD42024496716 and adheres to the Problem, Intervention, Comparison, and Outcomes framework (PICO). The analysis used Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We searched Embase, PubMed, DBLP, Google Scholar, IEEE Xplore, Cochrane database, IEEE, Web of Science, ArXiv, MedRxiv, and Semantic Scholar. The articles included were published between 2019 and 2023. Out of 1528 articles identified, thirty-seven met the inclusion criteria. ResultsWe compared AI-augmented Large Vessel Occlusion (LVO) detection and non-AI LVO detection in various patient processing times related to emergent endovascular therapy in acute ischemic strokes. Triage Time, Door-to-Intervention Notification Time (INR), and Door-to -Arterial Puncture Time revealed an odds ratio (OR) of 0.39 (95 % CI: 0.29–0.54, p < 0.001), 0.30 (95 % CI: 0.21–0.42, p < 0.001), and 0.50 (95 % CI: 0detection 0.30–0.82, p = 0.007), respectively -- all of which had negligible heterogeneity (I^2 = 0). CT-to-Puncture-Time and Door-to-CTA-Time yielded an OR of 0.57 (95 % CI: 0.31–1.04, p = 0.065) and 0.77 (95 % CI: 0.37–1.60, p = 0.489), respectively -- both of which had negligible heterogeneity (I^2 = 0). The Last Known Well (LWK) to Time of Arrival resulted in an OR of 1.15 (95 % CI: 0.83–1.59, p = 0.409, I^2 = 0). AI stroke detection sensitivity OR of 0.91 (95 % CI: 0.88–0.95, p < 0.001) should be interpreted with potential heterogeneity in mind (I^2 = 69.3). National Institute of Health score (NIHSS) mean of 16.20 (95 % CI: 14.96–17.45, p = 0.001, I^2 = 0). Patient Transfer-Times between primary and comprehensive stroke centers generated an OR of 0.98 (95 % CI: 0.73–1.32, p = 893, I^2 = 0). Similarly, Door-in-Door-Out Time (DIDO) had an OR of 1.19 (95 % CI: 0.21–6.88, p = 0.848) and low heterogeneity (I^2 = 5.1). The results indicated significant differences across several parameters between the AI augmentation and non-AI groups. ConclusionOur findings highlight how AI augments healthcare providers' ability to detect and manage strokes swiftly and accurately within acute care settings. As these technologies progress, healthcare organizations mature, and AI becomes more integrated into healthcare systems, longitudinal studies are critical in evaluating its impact on workflow efficiency, cost-effectiveness, and clinical outcomes.

Rescue Strategy for Hemorrhagic Complication During Mechanical Thrombectomy and the Clinical Outcome.

Hemorrhagic complications occasionally occur during mechanical thrombectomy and may lead to catastrophic outcomes. Therefore, remedial strategies require careful investigation. Herein, we aimed to evaluate a cohort of patients who experienced hemorrhage during endovascular procedures, the rescue methods used, and outcomes observed. This prospective study included patients who had hemorrhagic complications observed on digital subtraction angiography (DSA) during mechanical thrombectomy, between October 2017 and October 2022, at a high-volume stroke center. Functional outcomes were assessed using the modified Rankin scale (mRS) score at a 90-day follow-up. The primary outcomes were favorable outcomes (mRS score: 0-2 points) and mortality rates. The secondary outcomes were rescue therapy success rates, according to extravasation observed on the final DSA, recanalization status, and causes of hemorrhage. From October 2017 to October 2022, 1537 patients with stroke received emergency endovascular therapy, and 1147 patients completed a 90-day follow-up. Hemorrhage was observed in 33 (2.1%) patients in the process of endovascular interventions. Eighteen (54.5%) cases of hemorrhage were caused by microwire or microcatheter perforation. Mechanical stretching of the vessel during stent retriever withdrawal resulted in 8 (24.2%) cases of hemorrhage. Nine (27.3%) instances of hemorrhage stopped after the reversal of heparin administration and introduction of blood pressure control measures. Further endovascular rescue treatment was performed in 11 patients. Intracranial inflation of the balloon for tamponade stopped 10 hemorrhages, and 1 patient underwent additional coil embolization. Fifteen (45.5%) patients died within 90 days after the procedure. Three (9.1%) patients recovered functional independence (mRS score: 0-2 points) within 90 days. Hemorrhage during mechanical thrombectomy is a rare but severe complication of acute ischemic stroke with high mortality and disability rates. Intracranial inflation of a balloon for tamponade can effectively stop extravasation. This paper described haemorrhagic events characterised by contrast extravasation in the procedure of mechanical thrombectomy due to various causes. Although this complication is rare, patients showed a high mortality and disability rate. There are limited reports available. We found self-limiting haemorrhage had a rather benign prognosis and balloon tamponade could effectively stop the extravasation and might reduce the death rate within 90d. The methods we adopted could be applied in the clinical practice and help neuro-interventionist cope with this complication more promptly and effectively.

Factors Affecting Interfacility Transport Intervals in Stroke Patients Transferred for Endovascular Therapy

Objective To describe interfacility transfer (IFT) intervals, transfer vehicle type, and levels of care in patients with large vessel occlusion (LVO) strokes transferred for emergent endovascular therapy (EVT). Methods We included all patients transferred by a single IFT agency in the state of Indiana from July 1, 2018 to December 1, 2020 to a comprehensive stroke center in Indianapolis for emergent EVT. Data were collected from the transfer center electronic medical records and matched to IFT and receiving hospital data. Results Two hundred eighty-eight patients were included, of which 150 (52.0%) received EVT. The median call-to-needle interval (from call to the transfer center to EVT needle puncture) was 155.5 minutes (IQR 135.8-195.3). The median resource activation interval (call to the transfer center to IFT deployment) was 16 minutes (IQR 10-27 minutes); the median IFT response interval (call to IFT to arrival of the transferring unit) was 34 minutes (IQR 25-43 minutes); the median pre-transfer interval (call to the transfer center until departure from the sending hospital) was 60.4 minutes (IQR 47.1-72.6); and the median sending hospital interval at bedside was 25 minutes (IQR 20-30 minutes). Most patients (197, 68.4%) were sent via critical care rotor. Only 61 (21.2%) required interventions other than tissue plasminogen administration, such as titration of actively transfusing medications (e.g., nicardipine, propofol) (37 of 61, 59.7%), or intubation or ventilator management (25 of 61, 40.3%). Patients sent via critical care rotor had longer sending hospital intervals (26 minutes, IQR 22-32, vs 19 minutes, IQR 16-25; p < 0.001) but shorter transfer intervals than those sent via critical care ground. Conclusions At longer distances, rotor transport saved significant time specifically in the total IFT interval of patients with LVO strokes. Emphasizing processes to reduce the resource activation interval and the sending hospital interval may help reduce the overall time-to-EVT.

Novel score for predicting early emergency endovascular therapy in trauma care using logistic LASSO regression.

AimTo support decision‐making for early interventional radiology, this study aimed to derive and validate a novel and simple scoring system for predicting the necessity of interventional radiology therapies in trauma patients.MethodsThis retrospective study used data derived from the medical records of patients with severe traumatic injuries treated at a tertiary‐level emergency institution. The score was derived from 168 patients treated between April 2015 and October 2016 and validated using data from 68 patients treated between November 2016 and July 2017. Logistic “least absolute shrinkage and selection operator (LASSO)” regression was used to select predictors. In order to compose the score, odds ratios derived from the logistic model were simplified to integer score coefficients. The score was evaluated using the area under the receiver operating characteristic curve. The best cut‐off point for the score was determined using Youden’s index, and sensitivity and specificity were calculated.ResultsThe derived score comprised three predictors (systolic blood pressure, positive findings in abdominal ultrasound assessment, and pelvic fracture) and ranged from 0 to 30. On validation, the area under the receiver operating characteristic curve for the score was 0.86 (95% confidence interval, 0.64–1.00). The sensitivity and specificity were 80% and 89%, respectively, with a cut‐off point of 3.ConclusionThis simple score, requiring variables obtainable immediately after hospital arrival, could aid in facilitating early interventional radiology team activation.

Abstract 1122‐000210: Cangrelor to Prevent Intraluminal Thrombosis in Endovascular Therapy for Acute Stroke: Single Center Case Series

Introduction : Intraluminal thrombosis after endovascular therapy (EVT) is a peri‐procedural complication that carries a high burden of morbidity and mortality. The use of anti‐thrombotic therapies during EVT remains an evolving field. Recent surveys suggest the glycoprotein IIb/IIIa inhibitor, tirofiban, is often used during EVT. However, the increased intracranial hemorrhage risk and the medication’s long half‐life pose significant challenges to management. Cangrelor, an intravenous and reversible P2Y12 inhibitor, was first approved by FDA in 2015 for use in patients with coronary artery disease undergoing percutaneous intervention. Its rapid onset and offset are beneficial as an anti‐thrombotic during EVT. Our case series aim to characterize the safety and efficacy of cangrelor use in our institution and contribute towards its growing body of data. Methods : Chart review was conducted for patients that required endovascular therapy for acute stroke and received intravenous cangrelor at our center between January 2019 to December 2020. We included patients that underwent both extracranial and intracranial stent placement, as well as patients who suffered from intraluminal thromboses intra‐procedurally. Variables of interest included lesion pathophysiology, peri‐procedural complications including intraluminal re‐occlusion and intracranial hemorrhage, TICI score post‐procedurally, vessel patency and MRS on post‐hospitalization followup. Results : Nine patients received intravenous cangrelor during endovascular therapy. Mean age was 50 (range 41–67 years old), 3/9 patients were male. Seven patients (77.8%) had ischemic stroke, of whom five exhibited tandem intracranial occlusions and three required intraprocedural stent deployment. 3/7 patients received IV TPA prior to EVT. Interestingly, one patient had a previously placed Precise stent for acute internal carotid thrombus, briefly placed on eptifibatide (180mcg/kg), suffered from stent re‐occlusion on POD1 and required repeat thrombectomy with cangrelor intra‐procedurally; stent patency was maintained for the rest of her hospital course. One patient received balloon angioplasty of supraclinoid internal carotid artery. The remaining two patients required cangrelor for visualized intraluminal platelet aggregates during the EVT. Two patients presented with aneurysmal subarachnoid hemorrhage, one treated with flow diversion stent and the other requiring stenting for prolapsed aneurysm coiling. Dosing of cangrelor bolus and infusion varied. Six patients were bolused with 15 mcg/kg, while three patients received 7.5 mcg/kg. Infusion rates range from 0.5 to 4 mcg/kg/minute with all nine patients reaching therapeutic range P2Y12 levels on post‐procedural testing. Cangrelor infusion was transitioned to oral antiplatelet on post‐operative day 4 on average. In all nine patients, vessel and stent patency was maintained intra‐procedurally with cangrelor. Subsequent vascular imaging during hospitalization demonstrated no intraluminal thrombosis. One patient experienced intracranial hemorrhage, however they received intraprocedural eptifibatide (180mcg/kg) and cangrelor infusion (15 mcg/kg bolus, 2 mcg/kg/min) for their extensive clot burden and triple stent placement. Five patients attended three‐month post‐hospitalization followups. Their median MRS was 2 and all followup vessel imaging demonstrated patent vessels. Conclusions : Our case series demonstrate the promising efficacy of cangrelor in patients undergoing emergent endovascular therapy to prevent intraluminal thrombosis. Further studies with larger sample sizes can elucidate the optimal dose of cangrelor, length of treatment before oral transition, and compare its efficacy to eptifibatide.

Impact of COVID-19 on Acute Stroke Presentation in a Designated COVID-19 Hospital.

Objectives: Thousands of designated COVID-19 hospitals have been set up in China to fight the ongoing COVID-19 pandemic. Anecdotal reports indicate a falling rate of acute stroke diagnoses in these hospitals during the COVID-19 period. We conducted an exploratory single-center analysis to estimate the change in acute stroke presentation at the designated COVID-19 hospitals.Methods: This retrospective observational study included all patients admitted to Yongchuan Hospital Affiliated to Chongqing Medical University with acute stroke between January 24 and March 10, 2020. Patient demographics, characteristics of the stroke, treatment details, and clinical outcomes were compared with those of patients admitted in the corresponding period in the year before (2019, “the pre-COVID-19 period”). Subgroup analysis was performed in the ischemic and hemorrhagic stroke groups.Results: A total of 110 patients presented with acute stroke symptoms during the COVID-19 pandemic, compared with 173 patients in the pre-COVID-19 period. A higher proportion of stroke patients presented to the hospital via emergency medical services during the pandemic (48.2 vs. 31.8%, p = 0.006). There was a lower proportion of ischemic stroke patients (50.9 vs. 65.3%, p = 0.016) than in the preceding year. There were significantly fewer patients with 90-day modified Rankin Scale score ≥3 in the COVID-19 period compared with the pre-COVID-19 period (17.3 vs. 30.6%, p = 0.012). Among patients with ischemic stroke, the mean time from patient arrival to vessel puncture for emergency endovascular therapy in the COVID-19 period was shorter than that in the pre-COVID-19 period (109.18 ± 71.39 vs. 270.50 ± 161.51 min, p = 0.002). Among patients with hemorrhagic stroke, the rate of emergency surgical operation in the COVID-19 period was higher than that in the pre-COVID-19 period (48.1 vs. 30.0%, p = 0.047). The mean time from patient arrival to emergency surgical operation (15.31 ± 22.89 vs. 51.72 ± 40.47 min, p = 0.002) was shorter in the COVID-19 period than in the pre-COVID-19 period.Conclusions: Although fewer acute stroke patients sought medical care in this designated COVID-19 hospital during the COVID-19 pandemic, this type of hospital was more efficient for timely treatment of acute stroke. Recognizing how acute strokes presented in designated COVID-19 hospitals will contribute to appropriate adjustments in strategy for dealing with acute stroke during COVID-19 and future pandemics.

Detecting Large Vessel Occlusion at Multiphase CT Angiography by Using a Deep Convolutional Neural Network

Background Large vessel occlusion (LVO) stroke is one of the most time-sensitive diagnoses in medicine and requires emergent endovascular therapy to reduce morbidity and mortality. Leveraging recent advances in deep learning may facilitate rapid detection and reduce time to treatment. Purpose To develop a convolutional neural network to detect LVOs at multiphase CT angiography. Materials and Methods This multicenter retrospective study evaluated 540 adults with CT angiography examinations for suspected acute ischemic stroke from February 2017 to June 2018. Examinations positive for LVO (n = 270) were confirmed by catheter angiography and LVO-negative examinations (n = 270) were confirmed through review of clinical and radiology reports. Preprocessing of the CT angiography examinations included vasculature segmentation and the creation of maximum intensity projection images to emphasize the contrast agent-enhanced vasculature. Seven experiments were performed by using combinations of the three phases (arterial, phase 1; peak venous, phase 2; and late venous, phase 3) of the CT angiography. Model performance was evaluated on the held-out test set. Metrics included area under the receiver operating characteristic curve (AUC), sensitivity, and specificity. Results The test set included 62 patients (mean age, 69.5 years; 48% women). Single-phase CT angiography achieved an AUC of 0.74 (95% confidence interval [CI]: 0.63, 0.85) with sensitivity of 77% (24 of 31; 95% CI: 59%, 89%) and specificity of 71% (22 of 31; 95% CI: 53%, 84%). Phases 1, 2, and 3 together achieved an AUC of 0.89 (95% CI: 0.81, 0.96), sensitivity of 100% (31 of 31; 95% CI: 99%, 100%), and specificity of 77% (24 of 31; 95% CI: 59%, 89%), a statistically significant improvement relative to single-phase CT angiography (P = .01). Likewise, phases 1 and 3 and phases 2 and 3 also demonstrated improved fit relative to single phase (P = .03). Conclusion This deep learning model was able to detect the presence of large vessel occlusion and its diagnostic performance was enhanced by using delayed phases at multiphase CT angiography examinations. © RSNA, 2020 Online supplemental material is available for this article. See also the editorial by Ospel and Goyal in this issue.

Postcontrast CT to Estimate Arteriosclerotic Stenosis at the Site of Occlusion before Emergency Endovascular Treatment for Vertebral-Basilar Artery Occlusion.

Thrombectomy may be an effective therapy for vertebrobasilar artery (VBA) occlusion in addition to carotid or middle cerebral artery occlusion. Underlying arterial stenosis can be a cause of failure in thrombectomy; however, it is difficult to identify candidates with VBA occlusion before thrombectomy. The purpose of our study was to investigate whether postcontrast computed tomography (pcCT) is useful for identifying candidates with VBA occlusion for thrombectomy. In this retrospective study, we included patients who 1) were admitted to our institution between January 1, 2013, and July 1, 2019; 2) underwent pcCT; and 3) underwent emergency endovascular therapy for VBA occlusion. We defined no opacification of the top of the basilar artery (BA) in reconstructed coronal images of pcCT scans as distal BA occlusion and opacification of the top of the BA as distal BA open. We assessed the presence of underlying arterial stenosis at the site of occlusion according to angiographic findings during endovascular procedures. We also evaluated the relationship between the distal BA findings and the presence of underlying arterial stenosis. Thirty-two patients met our inclusion criteria and were analyzed. Among 19 patients with distal BA occlusion, none (0%) had ischemic stroke with underlying arterial stenosis. Among 13 patients with distal BA open, 4 (31%) were diagnosed with ischemic stroke without underlying arterial stenosis and 9 (69%) with underlying arterial stenosis (p <0.001). Distal basilar-artery findings in reconstructed coronal postcontrast CT images were useful for identifying candidates with VBA occlusion for thrombectomy.

Eptifibatide use following emergent carotid stenting in acute anterior circulation ischemic stroke with tandem occlusion

BackgroundEarly revascularization of the extracranial internal carotid artery in acute anterior circulation ischemic stroke (ACIS) is feasible and may improve clinical outcome. When a stent is deployed, antithrombotic agents should be administered peri-procedurally to ensure stent patency. Our institution implemented a protocol for the use of eptifibatide as a means of maintaining stent patency in the treatment of ACIS associated with cervical internal carotid artery occlusion. MethodsOur internal database was queried for patients who received emergent endovascular therapy (ET) for ACIS with stent placement and eptifibatide administration between July 2016 and 2019. ResultsTwenty nine patients met the study criteria. The etiology was large artery atherosclerosis in 26 cases. Two patients had a dissection (7%), and one had a carotid occlusion related to a recent carotid endarterectomy. Mean NIHSS was 14. Sixteen patients received IVrtPA. Extracranial-intracranial tandem occlusion (TO) was present in 21 of cases. All patients received an eptifibatide bolus followed by an infusion for approximately 24 hours post stent deployment. Head CT was obtained prior to initiation of oral dual antiplatelet therapy with aspirin and clopidogrel. Successful recanalization was achieved in all patients with no evidence of downstream embolization. Symptomatic intracerebral hemorrhage occurred in one patient. Stent occlusion occurred in two patients, only one of which was symptomatic. Favorable clinical outcome with mRS ≤ 2 at 3 months was achieved in seventeen patients. ConclusionsThe use of eptifibatide post procedure was associated with low risk of symptomatic intracranial hemorrhage, including in patients treated with rtPA.

Acute ischaemic stroke: a systematic review of the cost-effectiveness of emergency endovascular therapy using mechanical thrombectomy.

Although good evidence exists regarding the clinical effectiveness of mechanical thrombectomy for people with acute ischaemic stroke, cost-effectiveness should also be considered. The aim of this study was to systematically review the evidence of cost-effectiveness of emergency endovascular therapy using mechanical thrombectomy in the management of acute ischaemic stroke. The search was carried out in PubMed, EMBASE, Cochrane Library, and a grey literature search. Studies were included if they compared the costs and consequences of mechanical thrombectomy added to usual medical care compared to usual care alone for people with acute ischaemic stroke in the anterior and/or posterior region. Study quality was assessed using two appraisal tools tailored to economic evaluations. Thirteen studies were identified including twelve cost-utility analyses and one cost-benefit analysis. Studies could be dichotomised into those that evaluated first-generation (n = 4) and second-generation (n = 9) mechanical thrombectomy devices. Six studies had low applicability, six had moderate applicability, and one had high applicability to other settings. All cost-utility studies reported incremental cost-effectiveness ratios that would be considered cost-effective under typical willingness-to-pay thresholds. If the outcomes of the trials underpinning the evidence of clinical effectiveness can be replicated, then mechanical thrombectomy is likely to be cost-effective by typical willingness-to-pay thresholds. This finding holds under the assumption that no investment is required to develop stroke centres to the standard required to provide a safe emergency endovascular service and that additional expenditure on timely patient transport is not required.

A systematic review of the clinical effectiveness of emergency endovascular therapy using mechanical thrombectomy in acute ischaemic stroke: implications for service delivery.

Twelve randomised controlled trials (RCTs) comparing mechanical thrombectomy against traditional treatment options for patients experiencing acute ischaemic stroke (AIS) have been published. To evaluate whether this technology is more effective and/or safer than traditional treatment options and to assess the potential for implementation of this technology as a treatment strategy for acute ischaemic stroke in Ireland. RCTs published up to February 2017 were included. Meta-analysis was performed for two primary (mortality at 90days, mRS at 90days) and four secondary outcomes. Cumulative meta-analysis was used to investigate the point at which a consistent treatment effect was observed for outcomes that had a statistically significant pooled effect. Mechanical thrombectomy was associated with higher likelihood of being independent (mRS, p < 0.01; Barthel index, p < 0.01) at 90days post-AIS (p < 0.001). Cumulative meta-analysis demonstrated a consistent treatment effect in favour of mechanical thrombectomy after each trial was added to the analysis. There was no evidence of a difference in mortality rates (p = 0.21) or rates of SICH (p = 0.71) between patients randomised to intervention and control arms. Although the intervention appears to be associated with higher rates of any cerebral haemorrhage (p < 0.01) and recurrent ischaemic stroke (p = 0.03), considerable uncertainty remains as to these treatment effects. The trials published most recently have acted as a 'watershed' for mechanical thrombectomy, and while there are significant caveats, the data suggests that mechanical thrombectomy needs to be factored into the planning and delivery of services for the management of patients with acute ischaemic stroke in Ireland.

Abstract WP19: Transfer Selection for Endovascular Therapy of Ischemic Stroke within A Collaborative Network: Off-site Versus On-site Neurology Service

Introduction: Selection of patients for endovascular therapy (EVT) may depend on the hospital providing first line assessment. In our collaborative stroke network, we aimed to compare clinical characteristics and outcomes in ischemic stroke patients undergoing EVT who were transferred from telestroke hospitals following teleconsultation and in those transferred from hospitals providing on-site neurology service. Methods: We analyzed prospectively collected data from consecutive ischemic stroke patients who underwent emergent EVT at our comprehensive stroke center (01/2010 to 12/2014) after acute transfer from either telestroke hospitals or non-telestroke hospitals with on-site neurology service. We compared baseline characteristics, onset-to-EVT time, symptomatic intracranial hemorrhage (sICH), favorable functional outcome (mRS 0-2) at discharge and in-hospital mortality. Results: Among 133 transferred patients who underwent emergent EVT: median age 67 years (IQR, 15); 56% men; median NIHSS score 17 (21); 52% had anterior and 48% posterior circulation stroke. Sixty-five patients (49%) were transferred from telestroke and 68 (51%) from non-telestroke hospitals. Telestroke patients were less severely affected (median NIHSS scores: 15 [7] vs. 22 [20]; p=.0005) and more likely to have anterior circulation stroke (69% vs. 35%; p&lt;.0001) compared with non-telestroke patients. No between-group differences were present with regard to demographics, vascular risk factors, intravenous tPA rate and onset-to-EVT time. In-hospital mortality was lower among telestroke compared with non-telestroke patients (11% vs. 26%; p=.026). There were no differences in sICH (5% vs. 4%; p=1.0) and favorable functional outcome (17% vs. 18%; p=1.0). Conclusions: Patients transferred from telestroke hospitals were twice as often treated for anterior circulation stroke than those from non-telestroke neurological hospitals within our stroke network. This might be explained by more conservative selection of patients potentially amenable for EVT in hospitals harboring on-site neurology service but no EVT-capability. As our data was acquired prior to evidence from the positive EVT trials, further research is warranted to elaborate these findings.

The Evolution of Mechanical Thrombectomy for Acute Stroke.

The natural history of an acute ischemic stroke from a large vessel occlusion (LVO) is poor and has long challenged stroke therapy. Recently, endovascular therapy has demonstrated superiority to medical management in appropriately selected patients. This advance has revolutionized acute care for LVO and mandates a reevaluation of the entire chain of stroke care delivery, including patient selection, intervention, and post-procedural care. Since endovascular therapy is a therapy specifically targeting LVO, its application should be restricted to those patients only. Clinical and radiologic parameters need to be considered in patient selection. Data supports that all patients over the age of 18years presenting with a National Institutes of Health Stroke Scale (NIHSS) of 6 or greater within 6 hours of symptom onset should be considered for emergent endovascular therapy. Radiologically, those with a LVO of the internal carotid artery (ICA) or middle cerebral artery (MCA) M1 portion, intermediate or good collaterals and without large established infarct should be considered endovascular candidates. Selection beyond these parameters remains an open question and is being actively evaluated. In all cases, revascularization should be attempted with a new generation device (stentriever or direct aspiration), as these techniques are most likely to deliver adequate reperfusion. Post-revascularization, patients are closely monitored in an intensive care setting followed by discharge to rehabilitation, if required, or directly home. Patients should be evaluated in delayed fashion to assess recovery (typically at 3months post-treatment). Ultimately, the poor natural history of ischemic stroke from LVO and the potential significant benefit from endovascular therapy over medical management alone necessitate a national response to ensure we identify and treat all eligible patients as rapidly and effectively as possible.

Emergent endovascular stent grafting for saccular arch aneurysm complicated by aorto-esophageal fistula

Aneurysms of aortic arch are rare but amenable to endovascular therapy. Arch aneurysm presenting with aorto-esophageal fistula and hematemesis is a feared, but relatively rare complication. The extrapolation of the safety and rapidity of emergent endovascular repair for bleeding arch aneurysms has been infrequently reported. A bovine arch anatomy confers distinct advantages for endovascular therapy often avoiding a preceding debranching surgery. However, its endovascular treatment might be complicated by the nonhealing of fistula and potential risk for mediastinitis. Here, we report a case of a bovine aortic arch cystic aneurysm complicated by bleeding aorto-esophageal fistula, which warranted an emergent endovascular therapy. The prevertebral part of LSCA was plugged to interrupt the retrograde filling and a future endoleak. A nonhealing aorto-mediastinal fistula at follow-up was successfully treated by covered esophageal stenting. This report reiterates the importance of multidisciplinary approach with multispecialty collaboration to such complex spectrum of diseases.

Usefulness of Computed Tomography Perfusion in Treatment of an Acute Stroke Patient with Unknown Time of Symptom Onset

A 43-year-old Caucasian male with history of mechanical mitral valve was found down outside a recreational park shortly after daybreak. Examination on arrival to the emergency department revealed altered mental status, right hemiplegia, forced leftward gaze, and complete aphasia. Patient was ineligible for tissue plasminogen (TPA) therapy due to unknown time of symptom onset. Computed tomography angiogram (CTA) revealed occlusion of the left middle cerebral artery (MCA) with acute thrombus (Figure 1). Computed tomography perfusion scan (CTP) revealed a large ischemic penumbra with no evidence of infarcted brain tissue (Figure 2). The patient was taken for emergent endovascular therapy with successful retrieval of left MCA thrombus. The patient had almost complete resolution of symptoms with a pre-discharge National Institute of Health Stroke Scale of 1. History prior to discharge revealed that the patient was non-compliant and had been off of his warfarin therapy for months prior to the stroke. The patient was discharged home on warfarin and statin therapy. Figure 1 Transverse (left) and coronal (right) computed tomography angiogram demonstrating abrupt cutoff of the left middle cerebral artery at the site of the thrombus (marked by arrows). Figure 2 Computer-generated perfusion map demonstrating the region of the left cerebral hemisphere (CBF) with decreased cerebral blood flow and prolonged mean transit time (MTT) (marked by arrows). Note that this region of the brain has normal cerebral blood volume ... Acute stroke patients with unknown time of symptom onset are traditionally excluded from acute interventional therapy due to increased rates of fatal intracranial hemorrhage when patients with infarcted brain are treated with TPA or endovascular therapy beyond the recommended time windows.1,2 CTP of the brain is a rapid means of distinguishing between viable and non-viable brain tissue.3 Early in the course of stroke, there is prolonged mean transit time (MTT), decreased cerebral blood flow (CBF), and equal or greater cerebral blood volume (CBV) in ischemic areas of the brain. As brain tissue infarcts, both the CBF and CBV decrease. Assessment of differences between CBF and CBV in areas of brain with prolonged MTT allows one to determine both the size of the stroke as well as the amount of salvageable brain tissue. CTP has the potential to guide acute stroke interventional therapy in patients with unknown time of symptom onset.

E-028 The INterventional Stroke Therapy Outcomes Registry (INSTOR)

PurposeThe INterventional Stroke Therapy Outcomes Registry (INSTOR) was commissioned over a decade ago at the request of the Society of NeuroInterventional Surgery and the American Academy of Neurology Interventional Stroke...

Part Two: Against the Motion: It is not necessary to perform a randomised trial to compare open and endovascular repair of ruptured abdominal aortic aneurysms

anticipated from the literature. Irrespective of the reports of the good outcomes after endovascular repair from single expert centres or administrative databases, all these results are heavily confounded by patient selection and risks are under-reported. We need better evidence to guarantee the best outcomes for future patients with aneurysm rupture. We need to know whether an attempt at endovascular repair would be beneficial for all patients. It is only such knowledge that will drive changes in the provision of healthcare services to benefit future patients. The front cover of the Lancet issue of 26th September 2009, which published the IDEAL statements, carried this sentence: “It is incumbent on academic surgeons worldwide to transform what was once considered a comic opera into a dynamic world-class specialty”. We need to assess surgical innovations, including endovascular repair for ruptured aneurysm, rapidly in large, pragmatic RCTs.

Improved survival after introduction of an emergency endovascular therapy protocol for ruptured abdominal aortic aneurysms

The study was conducted to demonstrate improved survival (30-day mortality) after the introduction of an emergency endovascular therapy protocol for ruptured abdominal aortic aneurysms (rAAA). Numerous authors have successfully demonstrated reduced mortality in patients with rAAA using endovascular techniques. Comparison of endovascular aneurysm repair (EVAR) with open repair for rAAA may be misleading, however, because EVAR cannot be performed on all patients, and selection bias may explain the superior performance of any given surgical or endovascular strategy. We developed a model to predict mortality in patients before the introduction of EVAR (preprotocol population), applied this model to predict 30-day mortality among prospective patients (postprotocol population), and compared observed vs expected results. We assessed 126 patients with rAAA. Primary outcome was 30-day mortality. Potential confounding variables were age, sex, presurgical lowest recorded systolic blood pressure (SBP), and glomerular filtration rate (GFR). A logistic regression model incorporating significant confounders was used to evaluate changes in 30-day mortality for all patients with rAAA after introduction of the EVAR protocol. Separate logistic regressions were done to compare 30-day mortality for preprotocol vs patients receiving EVAR and preprotocol vs patients receiving postprotocol open repair. Cumulative sum (CUSUM) analysis was used to assess shifts in the performance of the rAAA program over time. Significant confounders were SBP, absence of SBP, and GFR. Logistic regression found evidence of lower mortality after the protocol was introduced, 17.9% vs 30.0% (odds ratio [OR], 0.385; 95% confidence interval [CI], 0.141 to 0.981; P = .046). Comparison of all open repairs (preprotocol and postprotocol) and EVAR demonstrated decreased risk for EVAR of 5.0% vs 28.3% (OR, 0.109; 95% CI, 0.013 to 0.906; P = .0084). Unstable patients (SBP <or=80) showed a trend towards improved survival with EVAR relative to open repair (14.3% vs 56.0%, P = .061). Comparison of preprotocol surgery with open repair after the introduction of the protocol found no evidence of a difference between mortality rates for the open procedures-30.0% (preprotocol) vs 25.0% (postprotocol; OR, 0.688; 95% CI, 0.335 to 1.415, P = .3031)-demonstrating that the improved performance observed with CUSUM analysis was related to the introduction of the EVAR protocol. Our predictive model using "weighted" CUSUM analysis (a measure of performance over time) demonstrated that a predefined strategy of management of rAAA that includes EVAR is associated with improved (P < .05) mortality. Unstable patients with rAAA may be particularly benefited by EVAR and should not be excluded from repair. Appropriate patients with rAAA who are undergoing treatment in experienced vascular centers should be offered EVAR as the treatment of choice.