Endovascular thrombectomy for acute ischaemic stroke with established large infarct: multicentre, open-label, randomised trial

BACKGROUND

Recent evidence suggests a beneficial effect of endovascular thrombectomy in acute ischaemic stroke with large infarct; however, previous trials have relied on multimodal brain imaging, whereas non-contrast CT is mostly used in clinical practice.

METHODS

In a prospective multicentre, open-label, randomised trial, patients with acute ischaemic stroke due to large vessel occlusion in the anterior circulation and a large established infarct indicated by an Alberta Stroke Program Early Computed Tomographic Score (ASPECTS) of 3-5 were randomly assigned using a central, web-based system (using a 1:1 ratio) to receive either endovascular thrombectomy with medical treatment or medical treatment (ie, standard of care) alone up to 12 h from stroke onset. The study was conducted in 40 hospitals in Europe and one site in Canada. The primary outcome was functional outcome across the entire range of the modified Rankin Scale at 90 days, assessed by investigators masked to treatment assignment. The primary analysis was done in the intention-to-treat population. Safety endpoints included mortality and rates of symptomatic intracranial haemorrhage and were analysed in the safety population, which included all patients based on the treatment they received. This trial is registered with ClinicalTrials.gov, NCT03094715.

FINDINGS

From July 17, 2018, to Feb 21, 2023, 253 patients were randomly assigned, with 125 patients assigned to endovascular thrombectomy and 128 to medical treatment alone. The trial was stopped early for efficacy after the first pre-planned interim analysis. At 90 days, endovascular thrombectomy was associated with a shift in the distribution of scores on the modified Rankin Scale towards better outcome (adjusted common OR 2·58 [95% CI 1·60-4·15]; p=0·0001) and with lower mortality (hazard ratio 0·67 [95% CI 0·46-0·98]; p=0·038). Symptomatic intracranial haemorrhage occurred in seven (6%) patients with thrombectomy and in six (5%) with medical treatment alone.

INTERPRETATION

Endovascular thrombectomy was associated with improved functional outcome and lower mortality in patients with acute ischaemic stroke from large vessel occlusion with established large infarct in a setting using non-contrast CT as the predominant imaging modality for patient selection.

FUNDING

EU Horizon 2020.

Delayed Functional Independence After Neurothrombectomy (DEFIANT) score: analysis of the Trevo Retriever Registry

BACKGROUND

Chronological heterogeneity in neurological improvement after endovascular thrombectomy (EVT) for large vessel occlusion (LVO) stroke is commonly observed in clinical practice. Understanding the temporal progression of functional independence after EVT, especially delayed functional independence in patients who do not improve early, is essential for prognostication and rehabilitation. We aim to determine the incidence of early functional independence (EFI) and delayed functional independence (DFI), identify associated predictors after EVT, and develop the Delayed Functional Independence After Neurothrombectomy (DEFIANT) score.

METHODS

Demographic, clinical, radiological, treatment, and procedural information were analyzed from the Trevo Registry (patients undergoing EVT due to anterior LVO using the Trevo stent retriever). Incidence and predictors of EFI (modified Rankin Scale (mRS) score 0-2 at discharge) and DFI (mRS score 0-2 at 90 days in non-EFI patients) were analyzed.

RESULTS

A total of 1623 patients met study criteria. EFI was observed in 45% (730) of patients. Among surviving non-EFI patients (884), DFI was observed in 35% (308). Younger age (p=0.003), lower discharge National Institutes of Health Stroke Scale (NIHSS) score (p<0.0001), and absence of any hemorrhage (p=0.021) were independent predictors of DFI. After age 60, the probability of DFI declines significantly with 5 year age increments (approximately 7% decline for every 5 years; p(DFI)= 1.3559-0.0699, p for slope=0.001). The DEFIANT score is available online (https://bit.ly/3KZRVq5).

CONCLUSION

Approximately 45% of patients experience EFI. About one-third of non-early improvers experience DFI. Younger age, lower discharge NIHSS score, and absence of any hemorrhage were independent predictors of DFI among non-early improvers.

Transjugular Intrahepatic Portosystemic Shunt in Liver Transplant Recipients: Outcomes in Six Adult Patients

OBJECTIVES

Transjugular intrahepatic portosystemic shunt (TIPS) is regularly used in treatment of clinically significant portal hypertension. Liver transplant recipients are, however, rarely indicated for the procedure. The study retrospectively examines the results of TIPS placement in 6 patients after OLT.

METHODS

4 males and 2 females (aged 36 to 62 years), treated with TIPS between 2007 a 2018, were included in the study. 5 patients had previously undergone liver transplantation for liver graft cirrhosis, 1 patient for Budd-Chiari syndrome. The piggyback caval reconstruction technique was selected in 4/6 cases. PH developed after OLT due to the recurrence of underlying liver condition and sinusoidal obstruction syndrome in half of the cases, respectively. Indications for TIPS were refractory ascites in 4 cases and variceal bleeding in 2 cases.

RESULTS

Standard TIPS technique was used and technical success was achieved in all cases with a procedure-related complication in 1 patient. One patient died shortly after TIPS placement. The remaining patients all reported regression of clinically significant PH. Late complications appeared in 2 patients. Liver retransplantation after TIPS creation was performed in 1 case. Median TIPS patency was 55 months. 2/6 patient continue to thrive with a patent shunt.

CONCLUSIONS

Transjugular intrahepatic portosystemic shunt in OLT recipients is technically feasible. Favorable clinical outcomes were reported particularly in patients treated for sinusoidal obstruction syndrome who were indicated to TIPS for refractory ascites.

Clinical effectiveness of endovascular stroke treatment in the early and extended time windows

BACKGROUND

The clinical efficacy of mechanical thrombectomy has been unequivocally demonstrated in multiple randomized clinical trials. However, these studies were performed in carefully selected centers and utilized strict inclusion criteria.

AIM

We aimed to assess the clinical effectiveness of mechanical thrombectomy in a prospective registry.

METHODS

A total of 2008 patients from 76 sites across 12 countries were enrolled in a prospective open-label mechanical thrombectomy registry. Patients were categorized into the corresponding cohorts of the SWIFT-Prime, DAWN, and DEFUSE 3 trials according to the basic demographic and clinical criteria without considering specific parenchymal imaging findings. Baseline and outcome variables were compared across the corresponding groups.

RESULTS

As compared to the treated patients in the actual trials, registry-derived patients tended to be younger and had lower baseline ASPECTS. In addition, time to treatment was earlier and the use of intravenous tissue plasminogen activator (IV-tPA) and general anesthesia were higher in DAWN- and DEFUSE-3 registry derived patients versus their corresponding trials. Reperfusion rates were higher in the registry patients. The rates of 90-day good outcome (mRS0-2) in registry-derived patients were comparable to those of the patients treated in the corresponding randomized clinical trials (SWIFT-Prime, 64.5% vs. 60.2%; DAWN, 50.4% vs. 48.6%; Beyond-DAWN: 52.4% vs. 48.6%; DEFUSE 3, 52% vs. 44.6%, respectively; all P > 0.05). Registry-derived patients had significant less disability than the corresponding randomized clinical trial controls (ordinal modified Rankin Scale (mRS) shift odds ratio (OR), P < 0.05 for all).

CONCLUSION

Our study provides favorable generalizability data for the safety and efficacy of thrombectomy in the "real-world" setting and supports that patients may be safely treated outside the constraints of randomized clinical trials.

Influence of time to endovascular stroke treatment on outcomes in the early versus extended window paradigms

BACKGROUND

The effect of time from stroke onset to thrombectomy in the extended time window remains poorly characterized.

AIM

We aimed to analyze the relationship between time to treatment and clinical outcomes in the early versus extended time windows.

METHODS

Proximal anterior circulation occlusion patients from a multicentric prospective registry were categorized into early (≤6 h) or extended (>6-24 h) treatment window. Patients with baseline National Institutes of Health Stroke Scale (NIHSS) ≥ 10 and intracranial internal carotid artery or middle cerebral artery-M1-segment occlusion and pre-morbid modified Rankin scale (mRS) 0-1 ("DAWN-like" cohort) served as the population for the primary analysis. The relationship between time to treatment and 90-day mRS, analyzed in ordinal (mRS shift) and dichotomized (good outcome, mRS 0-2) fashion, was compared within and across the extended and early windows.

RESULTS

A total of 1603 out of 2008 patients qualified. Despite longer time to treatment (9[7-13.9] vs. 3.4[2.5-4.3] h, p < 0.001), extended-window patients (n = 257) had similar rates of symptomatic intracranial hemorrhage (sICH; 0.8% vs. 1.7%, p = 0.293) and 90-day-mortality (10.5% vs. 9.6%, p = 0.714) with only slightly lower rates of 90-day good outcomes (50.4% vs. 57.6%, p = 0.047) versus early-window patients (n = 709). Time to treatment was associated with 90-day disability in both ordinal (adjusted odd ratio (aOR), ≥ 1-point mRS shift: 0.75; 95%CI [0.66-0.86], p < 0.001) and dichotomized (aOR, mRS 0-2: 0.73; 95%CI [0.62-0.86], p < 0.001) analyses in the early- but not in the extended-window (aOR, mRS shift: 0.96; 95%CI [0.90-1.02], p = 0.15; aOR, mRS0-2: 0.97; 95%CI [0.90-1.04], p = 0.41). Early-window patients had significantly lower 90-day functional disability (aOR, mRS shift: 1.533; 95%CI [1.138-2.065], p = 0.005) and a trend towards higher rates of good outcomes (aOR, mRS 0-2: 1.391; 95%CI [0.972-1.990], p = 0.071).

CONCLUSIONS

The impact of time to thrombectomy on outcomes appears to be time dependent with a steep influence in the early followed by a less significant plateau in the extended window. However, every effort should be made to shorten treatment times regardless of ischemia duration.

Mechanical thrombectomy performed in thrombosed fusiform aneurysm after surgery for craniopharyngioma in adult: Case report

INTRODUCTION

Fusiform dilatation of the internal carotid artery (ICA) is reported as a possible complication of craniopharyngioma resection in childhood. Here, the authors describe such a complication in an adult patient who presented with acute symptomatic thrombosis 7 months after surgery.

MATERIALS AND METHODS

A 45-year-old woman presented with left hemispheric stroke due to a thrombotic supraclinoid occlusion of the terminal ICA (so called "T" occlusion). Successful revascularisation was achieved with mechanical thrombectomy. Beside recanalization of the M1 middle cerebral artery segment and ICA, an irregular filling of the fusiform aneurysm of the communicating segment of the left ICA was observed. The patient recovered after mechanical thrombectomy with no clinical sequelae. Due to the persistent filling of the aneurysm sac, a flow diverter stent was deployed across the diseased vessel segment two weeks later. The patient underwent resection of the craniopharyngioma from ipsilateral pterional craniotomy 7 months ago. Five years later the patient works full time as a nurse with no regrowth of the craniopharyngioma and no aneurysm reperfusion.

RESULTS

This case, together with four other previously reported cases, documents that fusiform aneurysm as a complication of the craniopharygioma resection is not restricted to the childhood population but may also rarely occur in adults. As the patient suffered from acute symptomatic thrombosis which required treatment under the protocol for acute large vessel occlusions, we decided to treat the aneurysm with the flow diverter stent.

Abstract P467: Clinical Effectiveness of Endovascular Stroke Treatment in the Early and Extended Time Windows

Background and Purpose: The clinical efficacy of mechanical thrombectomy (MT) has been unequivocally demonstrated in multiple randomized clinical trials (RCTs). However, these studies were performed in carefully selected centers and utilized strict inclusion criteria. We aim to assess the clinical effectiveness of MT by comparing the specific RCT populations with corresponding patient cohorts derived from a prospective registry.

Methods: A total of 2008 patients from 76 sites across 12 countries were enrolled in a prospective open-label MT registry. Patients were categorized into the corresponding cohorts of the SWIFT-Prime, DAWN, and DEFUSE 3 trials based on the age, baseline NIHSS, occlusion site, IV tPA use, pre-morbid mRS and time to treatment criteria used in the RCTs without considering specific parenchymal imaging findings. Baseline and outcome variables were compared across the corresponding groups.

Results: As compared to the treated patients in the actual trials, registry-derived patients tended to be younger and had lower baseline ASPECTS. In addition, time to treatment was earlier and the use of IV tPA and general anesthesia were higher in DAWN- and DEFUSE 3-registry derived patients versus their corresponding trials. Reperfusion rates were higher in the registry patients. The rates of 90-day good outcome (mRS 0-2) in registry-derived patients were comparable to those of the patients treated in the corresponding RCTs (SWIFT-Prime, 64.5% vs 60.2%; DAWN, 50.4% vs 48.6%; Beyond-DAWN: 52.4% vs 48.6%; DEFUSE 3, 52% vs 44.6%, respectively; all P>0.05). Registry-derived patients had significant less disability than the corresponding RCT controls (ordinal mRS shift OR, P <0.05 for all).

Conclusion: Our study provides favorable generalizability data for the safety and efficacy of thrombectomy in the “real-world” setting and supports that patients may be safely treated outside the constraints of RCTs and strict guidelines.

First pass effect in patients with large vessel occlusion strokes undergoing neurothrombectomy: insights from the Trevo Retriever Registry

BACKGROUND

First pass effect (FPE), defined as near-total/total reperfusion of the territory (modified Thrombolysis in Cerebral Infarction (mTICI) 2c/3) of the occluded artery after a single thrombectomy attempt (single pass), has been associated with superior safety and efficacy outcomes than in patients not experiencing FPE.

OBJECTIVE

To characterize the clinical features, incidence, and predictors of FPE in the anterior and posterior circulation among patients enrolled in the Trevo Registry.

METHODS

Data were analyzed from the Trevo Retriever Registry. Univariate and multivariable analyses were used to assess the relationship of patient (demographics, clinical, occlusion location, collateral grade, Alberta Stroke Program Early CT Score (ASPECTS)) and device/technique characteristics with FPE (mTICI 2c/3 after single pass).

RESULTS

FPE was achieved in 27.8% (378/1358) of patients undergoing anterior large vessel occlusion (LVO) thrombectomy. Multivariable regression analysis identified American Society of Interventional and Therapeutic Neuroradiology (ASITN) levels 2-4, higher ASPECTS, and presence of atrial fibrillation as independent predictors of FPE in anterior LVO thrombectomy. Rates of modified Rankin Scale (mRS) score 0-2 at 90 days were higher (63.9% vs 53.5%, p<0.0006), and 90-day mortality (11.4% vs 12.8%, p=0.49) was comparable in the FPE group and non-FPE group. Rate of FPE was 23.8% (19/80) among basilar artery occlusion strokes, and outcomes were similar between FPE and non-FPE groups (mRS score 0-2, 47.4% vs 52.5%, p=0.70; mortality 26.3% vs 18.0%, p=0.43). Notably, there were no difference in outcomes in FPE versus non-FPE mTICI 2c/3 patients.

CONCLUSION

Twenty-eight percent of patients undergoing anterior LVO thrombectomy and 24% of patients undergoing basilar artery occlusion thrombectomy experience FPE. Independent predictors of FPE in anterior circulation LVO thrombectomy include higher ASITN levels, higher ASPECTS, and the presence of atrial fibrillation.

Stroke Imaging Selection Modality and Endovascular Therapy Outcomes in the Early and Extended Time Windows

BACKGROUND AND PURPOSE

Advanced imaging has been increasingly used for patient selection in endovascular stroke therapy. The impact of imaging selection modality on endovascular stroke therapy clinical outcomes in extended time window remains to be defined. We aimed to study this relationship and compare it to that noted in early-treated patients.

METHODS

Patients from a prospective multicentric registry (n=2008) with occlusions involving the intracranial internal carotid or the M1- or M2-segments of the middle cerebral arteries, premorbid modified Rankin Scale score 0 to 2 and time to treatment 0 to 24 hours were categorized according to treatment times within the early (0-6 hour) or extended (6-24 hour) window as well as imaging modality with noncontrast computed tomography (NCCT)±CT angiography (CTA) or NCCT±CTA and CT perfusion (CTP). The association between imaging modality and 90-day modified Rankin Scale, analyzed in ordinal (modified Rankin Scale shift) and dichotomized (functional independence, modified Rankin Scale score 0-2) manner, was evaluated and compared within and across the extended and early windows.

RESULTS

In the early window, 332 patients were selected with NCCT±CTA alone while 373 also underwent CTP. After adjusting for identifiable confounders, there were no significant differences in terms of 90-day functional disability (ordinal shift: adjusted odd ratio [aOR], 0.936 [95% CI, 0.709-1.238], P=0.644) or independence (aOR, 1.178 [95% CI, 0.833-1.666], P=0.355) across the CTP and NCCT±CTA groups. In the extended window, 67 patients were selected with NCCT±CTA alone while 180 also underwent CTP. No significant differences in 90-day functional disability (aOR, 0.983 [95% CI, 0.81-1.662], P=0.949) or independence (aOR, 0.640 [95% CI, 0.318-1.289], P=0.212) were seen across the CTP and NCCT±CTA groups. There was no interaction between the treatment time window (0-6 versus 6-24 hours) and CT selection modality (CTP versus NCCT±CTA) in terms of functional disability at 90 days (P=0.45).

CONCLUSIONS

CTP acquisition was not associated with better outcomes in patients treated in the early or extended time windows. While confirmatory data is needed, our data suggests that extended window endovascular stroke therapy may remain beneficial even in the absence of advanced imaging.

Aneurysm of pancreaticoduodenal arcade caused by medial arcuate ligament syndrome - case report and review of literature

INTRODUCTION

Visceral artery aneurysms are rare vascular pathologies. They are usually incidental findings during the examination for other reasons. The most common clinical symptoms are nonspecific abdominal pain and bleeding caused by their rupture, with a severe clinical presentation. Aneurysms of pancreaticoduodenal arcade are more common in patients with well-developed collateral circulation due to the coeliac trunk stenosis or occlusion.

CASE REPORT

In this case report the authors present a rare case of a patient with incidental finding of pancreaticoduodenal arcade aneurysm in the setting of severe stenosis of coeliac trunk origin caused by medial arcuate ligament compression. The diameter of the aneurysm was 40 mm and endovascular treatment was not possible because of unfavorable anatomical setting. The patient was successfully treated with resection of the aneurysm and the division of medial arcuate ligament during one surgery.

CONCLUSION

There is no correlation between the diameter and the risk of rupture of the pancreaticoduodenal arcade aneurysm. Because of high morbidity and mortality of their rupture, most authors recommend active treatment of these aneurysms. The necessity to treat truncus coeliacus stenosis or occlusion remains a controversial issue.

Computed Tomography (CT)-Navigated Translumbar Hemodialysis Catheters: A 10-Year Single-Center Experience

BACKGROUND In dialysis patients with exhausted usual central venous access sites, the translumbar hemodialysis catheter (TLC) provides a viable option for dialysis access. The technical success of catheter insertion, associated complications, and long-term patency of TLC were evaluated in this study. MATERIAL AND METHODS This retrospective study included 37 patients with occluded central thoracic veins in whom 39 TLC implantation procedures were performed and 196 patients with internal jugular vein hemodialysis catheters (JVC). TLC implantation was performed as a hybrid procedure with computed tomography (CT)-navigated translumbar inferior vena cava cannulation and subsequent fluoroscopy-guided hemodialysis catheter placement. RESULTS The rates of technical success of the implantations and minor periprocedural complications were 97.4% and 10.3% in the TLC group and 98.6% and 4.2% in the JVC group, respectively. The median follow-up in the TLC and JVC groups was 673 days and 310 days, respectively. The primary-assisted patency at the 1-year and 3-year follow-up was 88.7% and 72.0% in the TLC group and 81.6% and 67.0% in the JVC group, respectively, with no statistically significant difference between the 2 groups. The incidence rate of infection-related and patency-related complications calculated for 1000 catheter-days was 0.15 and 0.11 in the TLC group and 0.33 and 0.25 in the JVC group, respectively. CONCLUSIONS The CT-guided implantation of the TLC is a useful option to create dialysis access with a low complication rate and satisfactory long-term patency in patients without usual venous access.

Endovascular therapy in the distal neurovascular territory: results of a large prospective registry

BACKGROUND

There is a paucity of data regarding mechanical thrombectomy (MT) in distal arterial occlusions (DAO). We aim to evaluate the safety and efficacy of MT in patients with DAO and compare their outcomes with proximal arterial occlusion (PAO) strokes.

METHODS

The Trevo Registry was a prospective open-label MT registry including 2008 patients from 76 sites across 12 countries. Patients were categorized into: PAO: intracranial ICA, and MCA-M1; and DAO: MCA-M2, MCA-M3, ACA, and PCA. Baseline and outcome variables were compared across the PAO vs DAO patients with pre-morbid mRS 0-2.

RESULTS

Among 407 DAOs including 350 (86.0%) M2, 25 (6.1%) M3, 10 (2.5%) ACA, and 22 (5.4%) PCA occlusions, there were 376 DAO with pre-morbid mRS 0-2 which were compared with 1268 PAO patients. The median baseline NIHSS score was lower in DAO (13 [8-18] vs 16 [12-20], P<0.001). There were no differences in terms of age, sex, IV-tPA use, co-morbidities, or time to treatment across DAO vs PAO. The rates of post-procedure reperfusion, symptomatic intracranial hemorrhage (sICH), and 90-mortality were comparable between both groups. DAO showed significantly higher rates of 90-day mRS 0-2 (68.3% vs 56.5%, P<0.001). After adjustment for potential confounders, the level of arterial occlusion was not associated with the chances of excellent outcome (DAO for 90-day mRS 0-1: OR; 1.18, 95% CI [0.90 to 1.54], P=0.225), successful reperfusion or SICH. However, DAO patients were more likely to be functionally independent (mRS 0-2: OR; 1.45, 95% CI [1,09 to 1.92], P=0.01) or dead (OR; 1.54, 95% CI [1.06 to 2.27], P=0.02) at 90 days.

CONCLUSION

Endovascular therapy in DAO appears to result in a comparable safety and technical success profile as in PAO. The potential benefits of DAO thrombectomy should be investigated in future randomized trials.

Cardiovascular care of patients with stroke and high risk of stroke: The need for interdisciplinary action: A consensus report from the European Society of Cardiology Cardiovascular Round Table

Comprehensive stroke care is an interdisciplinary challenge. Close collaboration of cardiologists and stroke physicians is critical to ensure optimum utilisation of short- and long-term care and preventive measures in patients with stroke. Risk factor management is an important strategy that requires cardiologic involvement for primary and secondary stroke prevention. Treatment of stroke generally is led by stroke physicians, yet cardiologists need to be integrated care providers in stroke units to address all cardiovascular aspects of acute stroke care, including arrhythmia management, blood pressure control, elevated levels of cardiac troponins, valvular disease/endocarditis, and the general management of cardiovascular comorbidities. Despite substantial progress in stroke research and clinical care has been achieved, relevant gaps in clinical evidence remain and cause uncertainties in best practice for treatment and prevention of stroke. The Cardiovascular Round Table of the European Society of Cardiology together with the European Society of Cardiology Council on Stroke in cooperation with the European Stroke Organisation and partners from related scientific societies, regulatory authorities and industry conveyed a two-day workshop to discuss current and emerging concepts and apparent gaps in stroke care, including risk factor management, acute diagnostics, treatments and complications, and operational/logistic issues for health care systems and integrated networks. Joint initiatives of cardiologists and stroke physicians are needed in research and clinical care to target unresolved interdisciplinary problems and to promote the best possible outcomes for patients with stroke.

Should posterior cerebral artery occlusions be recanalized? Insights from the Trevo Registry

BACKGROUND AND PURPOSE

The purpose of this study was to evaluate the safety and effectiveness of mechanical thrombectomy (MT) in patients with acute ischaemic stroke related to isolated and primary posterior cerebral artery (PCA) occlusions amongst the patients enrolled in the multicentre post-market Trevo Registry.

METHOD

Amongst the 2008 patients enrolled in the Trevo Registry with acute ischaemic stroke due to large vessel occlusion treated by MT, 22 patients (1.1%) [10 females (45.5%), mean age 66.2 ± 14.3 years (range 28-91)] had a PCA occlusion [17 P1 (77.3%) and five P2 occlusions (22.7%)]. Recanalization after the first Trevo (Stryker, Fremont, CA, USA) pass and at the end of the procedure was rated using the modified Thrombolysis in Cerebral Infarction (mTICI) score. Procedure-related complications (i.e. groin puncture complication, perforation, symptomatic haemorrhage, embolus in a new territory) were also recorded. The modified Rankin Scale at 90 days was assessed.

RESULTS

Median National Institutes of Health Stroke Scale at admission was 14 (interquartile range 8-16). Stroke aetiology was cardio-embolic in 68.2% of cases. Half of the patients (11/22) received intravenous tissue plasminogen activator. 54.5% of the patients were treated under general anaesthesia. Reperfusion (i.e. mTICI 2b or 3) after first pass was obtained in 65% of cases. Final mTICI 2b-3 reperfusion was obtained in all cases. Only one (4.5%) procedure-related complication was recorded (puncture site) that resolved after surgery. At 90-day follow-up, modified Rankin Scale 0-2 was obtained in 59% of the patients and 9.1% died within the first 3 months after MT.

CONCLUSION

Mechanical thrombectomy for PCA occlusions seems to be safe (<5% procedure-related complications) and effective. Larger repository datasets are needed.

Trevo 2000: Results of a Large Real-World Registry for Stent Retriever for Acute Ischemic Stroke

Background Recent randomized controlled trials show benefit of thrombectomy for large vessel occlusion in stroke. Real-world data aid in assessing reproducibility of outcomes outside of clinical trials. The Trevo Retriever Registry is a multicenter, international, prospective study designed to assess outcomes in a large cohort of patients. Methods and Results The Trevo Registry is a prospective database of patients with large vessel occlusion treated with the Trevo device as the first device. The primary end point is revascularization based on modified Thrombolysis in Cerebral Infarction score and secondary end points include 90-day modified Rankin Scale, 90-day mortality, neurological deterioration at 24 hours, and device/procedure related adverse events. Year 2008 patients were enrolled at 76 centers in 12 countries. Median admission National Institutes of Health Stroke Scale was 16 (interquartile range, 11-20). Occlusion sites were internal carotid artery (17.8%), middle cerebral artery (73.5%), posterior circulation (7.1%), and distal vascular locations (1.6%). A modified Thrombolysis in Cerebral Infarction 2b or 3 was achieved in 92.8% (95% CI, 91.6, 93.9) of procedures, with 55.3% (95% CI, 53.1, 57.5) of patients achieving modified Rankin Scale ≤2 at 3 months. Patients meeting revised 2015 American Heart Association criteria for thrombectomy had a 59.7% (95% CI , 56.0; 63.4) modified Rankin Scale 0 to 2 at 3 months, whereas 51.4% treated outside of American Heart Association criteria had modified Rankin Scale 0 to 2. 51.4% (95% CI , 49.6, 55.4). Symptomatic intracranial hemorrhage rate was 1.7% (95% CI , 1.2, 2.4). Conclusions The Trevo Retriever Registry represents real-world data with stent retriever. The registry demonstrates similar reperfusion rates and outcomes in the community compared with rigorous centrally adjudicated clinical trials. Future subgroup analysis of this cohort will assist in identifying areas of future research. Clinical Trial Registration URL : https://www.clinicaltrials.gov . Unique identifier: NCT 02040259.

Abstract WP37: Real-World Applicability of Thrombectomy in Anterior Circulation Large Vessel Occlusion Strokes Treated in the Extended Window: Analysis of the Prospective Trevo Registry

Background: Two recent trials showed a strong benefit of thrombectomy in the extended window. However, these studies were performed in selected centers and utilized strict inclusion criteria. We aim to evaluate the outcomes of thrombectomy in a large prospective cohort treated outside the rigid clinical trial setting.

Methods: Trevo Registry patients with ICA, MCA-M1 or M2 occlusions and pre-morbid mRS0-2 were categorized according to time-from-last-seen-well (TLSW) to puncture as early (0-6hours) vs. late (6-24hours). Uni- and multivariate analyzes were performed to identify good outcome (90-day mRS0-2) predictors. Subgroup analyses were performed for the basic DAWN (age >=18, NIHSS >=10, ICA or M1 occlusion, pre-morbid mRS 0-1) and DEFUSE 3 (age 18-90, NIHSS >=6, ICA or MCA-M1 occlusion, mRS 0-2) trial criteria.

Results: As compared to the late (n=430), early patients (n=1173) were older (70 vs 68, p=0.011) and had higher IV tPA use (69 vs 25%, p<0.001), lower smoking frequency (33 vs 40%, p=0.011), larger baseline infarcts (21.2 vs 15.6 cc, p=0.045), less frequent ICA occlusions (18 vs 24%, p=0.015), and a trend towards higher admission NIHSS (16 vs 15, p=0.09). Despite significantly longer TLSW to puncture (3.5 vs 9.6 h, p<0.001), late patients had similar rates of mTICI2b-3 (92 vs 94%, p=0.20), good outcomes (60 vs 56%, p=0.128), symptomatic ICH (1.5 vs.1.4%, p=0.84), and 90-day-mortality (10.9 vs.11.4%, p=0.79). Age (OR 0.96, 95%CI [0.96-0.97]), admission-NIHSS (0.91 [0.89-0.93]), baseline mRS (0.49 [0.40-0.60]), ASPECTS >= 6 (1.37 [1.07-1.75]), DM (0.58 [0.44-0.77]), and time to treatment (0.98 [0.97-1.00]) were independent predictors of good outcomes. Imaging modality did not predict outcomes. Similar findings were observed in the early versus late DAWN-like (n=709 vs 257) and DEFUSE 3-like (n=855 vs 273) cohorts. There was great similarity between the outcomes of the Trevo Registry subsets vs their analogous RCTs: early DAWN-like vs SWIFT Prime (90-day mRS 0-2: 57.5 vs 60%; 90-day mRS 6: 11.% vs 9%), Late DAWN-like vs DAWN (50.2 vs 48.6%; 10.6 vs 18%), and Late DEFUSE 3-like vs DEFUSE 3 (52 vs 45%; 10.3 vs 14%).

Conclusions: Our study provides favorable data for the generalizability of the safety and efficacy of thrombectomy in the “real-world” setting.

Abstract WP111: Who Needs Neuroprotection With Endovascular Stroke Therapy? Findings From the Trevo Retriever Registry

Background: Combined neuroprotection with endovascular therapy may improve clinical outcomes of only a subset of individuals treated for acute ischemic stroke. The risk/benefit profile of adjunctive treatment may not warrant neuroprotection with successful reperfusion, yet many other individuals have poor outcomes despite revascularization. We hypothesized that optimal candidates for adjunctive neuroprotection may be defined by analyses of subjects with poor clinical outcome despite successful reperfusion in the Trevo Retriever Registry.

Methods: The Trevo Retriever Registry dataset was analyzed to define the subset of cases with poor clinical outcome (day 90 mRS 4-6) after successful reperfusion (eTICI 2b50, 2b67, 2c, 3). Multivariate analyses were used to identify predictors of poor outcome using these distinct definitions of successful reperfusion. The influence of covariates, including TLSW, baseline clinical and imaging variables (e.g. ASPECTS, ASITN collateral grade), on defining such optimal neuroprotective candidates was delineated.

Results: Successful reperfusion adjudicated by core lab, defined as eTICI ≥ 2b50 included 1,162 subjects, with eTICI ≥ 2b67 in 920, eTICI ≥ 2c in 652 and eTICI 3 in 209. Poor outcome (day 90 mRS 4-6) occurred in 316/1162 (27%) with eTICI ≥ 2b50, 243/920 (26%) with eTICI ≥ 2b67, 172/652 (26%) with eTICI ≥ 2c and 61/209 (29%) with eTICI 3. Across all subsets, multivariate analyses to predict poor outcome after successful reperfusion identified increased age (per year, OR 1.04-1.05, all p=<0.02) as a factor, adjusting for withdrawal of care. Expectedly, greater baseline NIHSS severity predicted greater day 90 disability (OR 1.07-1.08, all p<0.001). TLSW was a predictor only with eTICI ≥ 2b50 (per hour, OR 1.02, p=0.039). History of diabetes was a factor only with eTICI ≥ 2b50 and eTICI ≥ 2b67 (OR 2.05-2.19, p<0.001). Worse collateral grade (ASITN 0-1) was the most potent predictor (OR 2.27-2.71 versus ASITN 2, p=0.027-0.052; OR 3.85-4.35 versus ASITN 3-4, all p=0.003).

Conclusions: Neuroprotection combined with endovascular therapy may optimally target stroke patients with worse collaterals, diabetes or increased age. Trial design for neuroprotection with revascularization in AIS should leverage these data.

Abstract WMP4: Fast versus Slow Progressors in Real-World Data From the Trevo Retriever Registry: Collaterals Dominate Time to Reperfusion in Clinical Outcome After Thrombectomy

Background: Time to reperfusion (TTR) is commonly cited in clinical outcome after endovascular treatment of acute ischemic stroke, yet collaterals may set the pace of ischemia. Real-world data on fast and slow progressors also remain scarce. We analyzed the impact of TTR on clinical outcome in real-world data using core lab adjudicated angiography, interventional steps and corresponding reperfusion.

Methods: 16 key time intervals were calculated from workflow (time of symptom onset, door, picture, puncture) and core lab metrics (clot visualization, first deployment, first reperfusion, final angiography) in real-world data from the Trevo Retriever Registry. These 16 variations of TTR were analyzed overall and by collateral status (ASITN 0-1 versus 2 versus 3-4) to determine the relationship with 90-day clinical outcomes.

Results: Real-world data on endovascular therapy from 1,441 subjects in the Trevo Retriever Registry were analyzed to relate TTR with clinical outcomes. Overall metrics for TTR are shown in Table 1. TTR was not linked with collateral status. Using a multivariate model incorporating known predictors, there was no influence of TTR using any of the 16 definitions on clinical outcome. Better collateral status on DSA prior to revascularization showed a potent relationship with 90-day mRS (p<0.001) and better probability of functional independence (aOR 1.4, 95% CI 1.2, 1.7) per grade of collateral flow.

Conclusions: Collaterals transform time to reperfusion, linking fast and slow progressors with subsequent clinical outcomes. TTR may be standardized based on these 16 key epochs in endovascular stroke therapy to document workflow metrics. Time is relative, even when measured with detailed, standardized metrics.

Are you suffering from a large arterial occlusion? Please raise your arm!

Background and purpose

Triage tools to identify candidates for thrombectomy are of utmost importance in acute stroke. No prognostic tool has yet gained any widespread use. We compared the predictive value of various models based on National Institutes of Health Stroke Scale (NIHSS) subitems, ranging from simple to more complex models, for predicting large artery occlusion (LAO) in anterior circulation stroke.

Methods

Patients registered in the SITS international Stroke Register with available NIHSS and radiological arterial occlusion data were analysed. We compared 2042 patients harbouring an LAO with 2881 patients having no/distal occlusions. Using binary logistic regression, we developed models ranging from simple 1 NIHSS-subitem to full NIHSS-subitems models. Sensitivities and specificities of the models for predicting LAO were examined.

Results

The model with highest predictive value included all NIHSS subitems for predicting LAO (area under the curve (AUC) 0.77), yielding a sensitivity and specificity of 69% and 76%, respectively. The second most predictive model (AUC 0.76) included 4-NIHSS-subitems (level of consciousness commands, gaze, facial and arm motor function) yielding a sensitivity and specificity of 67% and 75%, respectively. The simplest model included only deficits in arm motor-function (AUC 0.72) for predicting LAO, yielding a sensitivity and specificity of 67% and 72%, respectively.

Conclusions

Although increasingly more complex models yield a higher discriminative performance for predicting LAO, differences between models are not large. Assessing grade of arm dysfunction along with an established stroke-diagnosis model may serve as a surrogate measure of arterial occlusion-status, thereby assisting in triage decisions.

A randomized controlled trial to test efficacy and safety of thrombectomy in stroke with extended lesion and extended time window

RATIONALE

The benefit of thrombectomy in patients with intracranial large vessel occlusion of the anterior circulation has been shown in selected patients in previous randomized controlled trials, but patients with extended ischemic lesions were excluded in the majority of these trials. TENSION aims to demonstrate efficacy and safety of thrombectomy in patients with extended lesions in an extended time window (up to 12 h from onset or from last seen well).

DESIGN

TENSION is an investigator-initiated, randomized controlled, open label, blinded endpoint, European, two-arm, postmarket study to compare the safety and effectiveness of thrombectomy as compared to best medical care alone in stroke patients with extended stroke lesions defined by an Alberta Stroke Program Early Computed Tomography Scan score of 3-5 and in an extended time window. In an adaptive design study, up to 665 patients will be randomized.

OUTCOMES

Primary efficacy endpoint will be clinical outcome defined by the modified Rankin Scale at 90-day poststroke. The main safety endpoint will be death and dependency (modified Rankin Scale 4-6) at 90 days. Additional effect measures include adverse events, health-related quality of life, poststroke depression, and costs utility assessment.

DISCUSSION

TENSION may make effective treatment available for patients with severe stroke in an extended time window, thereby improving functional outcome and quality of life of thousands of stroke patients and reducing the individual, societal, and economic burden of death and disability resulting from severe stroke. TENSION is registered at ClinicalTrials.gov (ClinicalTrials.gov Identifier NCT03094715).

Correction to: Multidisciplinary approach in the treatment of spinal dural arteriovenous fistula-results of endovascular and surgical treatment

The author J. Adamkov was incorrectly captured in the original article and is now corrected in this article.

Endovascular Treatment of Symptomatic Thoracic Aneurysm Due to Periaortic Lymphoma

An aggressive periaortic lymphoma could very rarely invade the aortic wall. We present a unique case of a patient with symptomatic thoracic aneurysm and imminent rupture due to the periaortic lymphoma, in which endovascular treatment using stent graft was applied. After stabilization of the aorta and histological confirmation of aggressive B-cell lymphoma by computed tomography-guided biopsy, the antilymphoma therapy was initiated. Despite the full treatment, the patient died 12 months later.

Abstract 109: Trevo 2000: Results of the Largest Real-World Registry for Stent Retriever for Acute Ischemic Stroke

Objective: The Trevo Registry was designed to assess real world outcomes of the Trevo Retriever in patients experiencing ischemic stroke. It is the largest prospective study for acute stroke intervention, with 2010 patients enrolled and 90 day outcomes in 1873 patients. The primary endpoint is revascularization status based on post-procedure TICI score and secondary endpoints include 90-day mRS, 90-day mortality, neurological deterioration at 24 hours and device/procedure related adverse events.

Methods: The study was a prospective, open-label, consecutive enrollment, multi-center, international registry of patients who underwent mechanical thrombectomy for acute stroke using the Trevo stent retriever as the initial device.

Results: The median NIHSS at admission was 16 (IQR 11-20). Most patients (70.8%) were treated at <= 6 hours from last known normal with a median procedure time of 50 minutes (32-77). The occlusion site was M1 or M2 in 73.9%. General anesthesia was employed in 43.5% of procedures. TICI 2b or 3 revascularization was 92.8% with an average of 1.7 passes with the device. Median NIHSS at 24 hours and discharge was 6 and 4 respectively. Fifty-five percent (55.2%) of patients had mRS ≤2 at 3 months and the overall mortality rate was 13.8%. Patients treated after 8 hours of symptom onset had a 95% revascularization rate and 51.2% mRS ≤2 at 3 months. The symptomatic ICH rate was 1.6%. Patients who met the revised AHA criteria for thrombectomy were found to have 59.5% mRS 0-2 at 90 days.

Conclusions: The Trevo Retriever Registry represents the first real world data with stent retriever use in the era of clinical trials showing the overwhelming benefit of stent retrievers to treat acute ischemic stroke. Due to the fact that this data represents real world use of the Trevo Retriever, (e.g. subjects pre-stroke mRS >1 (29%) and those treated 6-24 hours after stroke symptoms (29%), this data cannot be compared to the results from recent trials with restricted eligibility criteria. Future subgroup analysis of this large cohort will help to identify areas of future research to enhance outcomes further with this treatment modality.

Abstract 63: Collaterals in Thrombectomy for MCA Occlusion: Mapping the Collaterome in the Trevo Retriever Registry

Background: The delay and dispersion of collateral circulation to the MCA territory is readily available prior to endovascular thrombectomy for acute ischemic stroke (AIS). Factors associated with collateral grade have never been established in such an extensive population, reflecting diverse subjects from around the world. Largescale data from the Trevo Retriever Registry enables mapping of the MCA collaterome for the first time.

Methods: The Imaging and Angiography Core Lab of the Trevo Retriever Registry independently conducted prospective evaluation of angiography in more than 1,500 subjects. Collaterals were systematically scored using ASITN grade prior to thrombectomy. Descriptive statistics detailed the distribution of collateral grades and analyses with demographic, imaging and clinical variables to explore key associations with routinely acquired registry data.

Results: 890 subjects (68.5 ± 15.1 years; 54.6% women; baseline NIHSS median 15 (10-19)) with AIS due to MCA occlusion had angiography of collateral circulation centrally adjudicated. Proximal M1 MCA occlusion was noted in 671/890 (75.4%). Collateral grade prior to thrombectomy included grade 4 or most robust collaterals in 38/890 (4.3%), 3 in 294/890 (33.0%), 2 in 467/890 (52.5%), 1 in 80/890 (9%) and 0 or none in 11/890 (1.2%). Baseline collaterals at angiography and pre-procedure ASPECTS were closely correlated (r=0.439, p<0.001) with more modest correlation between collateral grade and CTP/DWI (rrCBF<30% or ADC<620) infarct core (r=-0.31, n=391; p<0.001) or CTP/PWI (Tmax>6s) hypoperfusion at-risk (r=-0.10, n=391; p=0.043) volumes. First pass mTICI≥2b occurred in 553/858 (64.5%) with final mTICI≥2b in 824/890 (92.6%). Collateral grade prior to thrombectomy (each 1-point increment, after adjustment for other predictors) was strongly associated (OR 1.38 95%CI (1.12-1.7), p=0.002) with good clinical outcomes (mRS 0-2) at 90 days.

Conclusions: Largescale mapping of collaterals prior to MCA thrombectomy reveals marked variation in the extent and functional impact of the collaterome. The preponderance of partial perfusion in the downstream ischemic territory prompts the need to investigate and leverage the protective nature of the collaterome in AIS.

Abstract WP8: Global Real World Evidence of Balloon Guided Stent Retriever Thrombectomy

Background and Aims: Balloon Guide Catheter (BGC) use during thrombectomy treatment in Stroke patients has been reported to have positive effects on revascularization, procedural characteristics, and clinical outcomes. We evaluate the use of BGC in an open-label large prospective TREVO Retriever Registry of real world patients to determine predictors of good ‘clinical’ outcomes.

Method: Consecutive Trevo Registry patients that had Balloon Guide Catheter (BGC) used during their thrombectomy procedure were identified; a subset of patients who fulfilled the criteria (ICA and/or MCA-M1/M2 occlusion with pre-morbid mRS 0-1, TLSW ≤6 hrs) within the cohort were also identified. Multivariate analysis was performed to identify the predictors of good outcomes in BGC thrombectomy patients.

Results: A total of 1031 BGC treated Trevo Registry patients (overall enrolled, n=2010) qualified for analysis, of which 605 patients fulfilling the subset criteria were identified. The mean age of BGC/stent retriever patients was 67.5 with a median (IQR) baseline NIHSS of 15(11-19). Occlusion location of the BCG group was ICA -20.4%, M1- 57.1%, M2/M3-20.3%, and Posterior 1.8%.

In the overall BGC cohort, the median (IQR) time to treatment was (4.2 (3.0,6.5)- hrs.) with conscious/local sedation used in 63.4% and general anesthesia used in 37.3% of cases. The median number of passes with Trevo stent retriever was 1 and revascularization (mTICI ≥ b) was achieved in 92.8% of cases. The sICH rate was low at 1.9% (20/1031) with a low rate of vessel perforation (0.2%). At 90 days post stroke, 56.0% of patients achieved functional independence (mRS 0-2) with 63.7% of the subset of “guidline “ BGC patients achieving functional independence at 90 days. Multivariate logistic regression showed age (aOR 0.97 [0.96, 0.99] P <0.001), Diabetes (aOR 0.67, [0.18,0.98] P =0.03), conscious sedation vs general anesthesia ( aOR 1.7 [1.2,2.3], P= 0.002, number of passes (aOR 0.76 [0.66-0.88],P <0.001), pre stroke mRS (aOR 0.54 [0.45-0.65], P <0.0010 and NIHSS (aOR 0.93 [0.91-0.95], P <0.001) as predictors of functional independence .

Conclusion: Data from Trevo Registry demonstrate the use of BGC in thrombectomy procedure is safe, and leads to a reduction of disability in ischemic stroke patients.

Abstract 112: Identifying Patients Who May Benefit From Thrombectomy in the Late Time Window: Predictors of Good Outcome Beyond Advanced Imaging

Background: The DAWN trial showed EVT effectiveness in the late time window (6-24 hrs), however, DAWN patients were carefully selected based on advanced perfusion imaging, CTP and MRI. Similar to the early window (0-6 hrs), simple imaging (CT) and other clinical variables may select patients for thrombectomy beyond 6 hours. We evaluated a largescale, real world practice for predictors that could identify patients who may benefit from EVT in the late time window.

Methods: Patients with LVO in the anterior circulation (M1, M2, ICA) from a prospective, single arm, multicenter, international registry (Trevo Retriever Registry) treated in the late window LSN to groin puncture (GP) (6-24 hrs) were included. Univariate and multivariate analyses assessed factors independently correlating with good outcome (90 day mRS 0-2). Furthermore, patients outcomes were compared based on their baseline imaging selection CT vs CTP and MRI.

Results: 549 patients were treated beyond 6 hours. The average age was 67, median/IQR ASPECTS 8(6-9), median/IQR NIHSS was 15 (9-20), median/IQR time LSN to GP (hr) was 9.7 (7.3-13.6) and IV-tPA rate were 22.8%. CT was the only imaging selection method in 15.9%, while additional advanced imaging was utilized in the remaining patients; CTP (70%), and MRI(14.1%). Good outcomes were observed in 51.4% of late window patients. Age (aOR 0.96, 95% CI 0.94-0.98, p<0.001), stroke severity by NIHSS (aOR 0.9, 95% CI 0.86-0.95, p<0.001) and ASPECTS (for each point increment in ASPECTS aOR 1.24, 95% CI 1.05-1.47, p=0.012) were independent pre-intervention predictors of good outcome in the late window. The addition of advanced imaging beyond CT, including CTP or MRI, did not confer higher correlation with good outcome (aOR 1.45, 95% CI 0.77-2.73, p=0.25). Good outcome was achieved in 56% of CT selected patients as compared to 53% patients selected by CTP or MRI.

Conclusion: Simple imaging and clinical variables can identify patients that could benefit from thrombectomy in the late window. Importantly, ASPECTS reliably predicted good outcome beyond 6 hours without adjunctive benefit from adding advanced perfusion imaging, a finding that may simplify patients selection to facilitate and generalize the intervention in the late window to wide, real world practice.

Abstract TP29: Endovascular Therapy for Distal Occlusions in the Early and Late Window: an Extension in Location and Time

Background: Endovascular therapy (EVT) effectiveness is established in ischemic strokes with large vessel occlusion (LVO) in the terminal ICA and M1, which was extended up to 24 hrs by recent DAWN trial results. However this benefit is not as well established in more distal (M2) occlusions, especially late presenters (beyond 6 hrs). We evaluated thrombectomy outcomes in M2 occlusions as compared to ICA/M1 across early and late time windows.

Methods: In a prospective, multicenter, single arm, international registry (Trevo Retriever Registry), anterior circulation LVOs were stratified on clot location into M2 vs ICA/M1 and dichotimized into early vs late (0-6 vs 6-24 hrs). 90 day mRS (0-1 excellent, 0-2 good) were the primary outcomes; sICH and dissection were the secondary (safety) outcomes. Multivariate analyses identified pre-procedure variables independently correlating with good outcome in M2s.

Results: 1581 patients were identified (1265 ICA/M1, 316 M2). The M2 and ICA/M1 groups were similar (age in both 68.4), IV-tPA (69.1 vs 69.7%, p=0.8) and same median/IQR ASPECTS 8 (7-9). M2 patients had lower NIHSS (13 vs 16, p<0.001). Higher good and excellent outcomes were observed in M2s (65.8% and 51.3%) compared to ICA/M1 (57.9% and 42.8%) (p=0.01). Similar outcomes were maintained beyond 6 hrs (64.8% good, 45.9% excellent in M2s vs 53.8% and 38.4% in ICA/M1) (p=0.08). Fig 1 shows the probabilities of good outcome in M2 vs ICA/M1 in relation to time, illustrating no association with time (p=0.4). Similar safety profiles were seen: sICH (0% M2 vs 0.7% ICA/M1, p=1.0) and dissections (0.3% M2 vs 0.4% ICA/M1, p=0.22). Age (aOR 0.96, 0.94-0.98 95% CI, p<0.001) and NIHSS (aOR 0.94, 0.9-0.98 95% CI, p<0.001) correlated with good outcome in M2, while IV-tPA did not have adjunctive benefit (aOR 0.72, 0.42-1.24 95% CI, p=0.24).

Conclusion: Excellent and good outcomes may be achieved in distal LVO isolated to M2 similar to those with proximal occlusions. A benefit that can be reached up to 24 hrs.

Abstract WP34: Endovascular Treatment in Large Core Strokes

Introduction: The recent thrombectomy trials were largely limited to patients with small strokes on presentation.

Methods: Patients derived from a large prospective multinational stent-retriever registry (Trevo Registry, n=2,010). Baseline NCCT SPECTS and CTP Core Volumes (rCBF<30%) were adjudicated by a Core Lab. Baseline and outcome variables were compared for ASPECTS 0-5 vs. 6-10 on NCCT and large age-adjusted cores (>70mL if age <=70 years; >50mL if age >70-80 years; >30mL if age >80 years) vs. not on CTP. The primary and secondary efficacy endpoint were the rates of 90-day mRS 0-2 and mTICI 2b-3, respectively. Safety endpoints included sICH and 90-day mortality.

Results: As compared with patients with higher baseline ASPECTS (n=1037), low baseline ASPECTS (0-4, n=78; 5, n=78) patients were younger, had higher stroke severity, and tend to have less comorbidities and undergo thrombectomy at later times (Table 1a). TICI-3 reperfusion was higher in the higher-ASPECTS group but other reperfusion outcomes were nearly the same. Safety outcomes were comparable. Rates of 90-day mRS 0-2 were significantly higher in the high-ASPECTS group (p<0.001); however, 41.8% of ASPECTS 0-5 patients were independent at 90 days and safety outcomes were similar (Table 1b). Analysis according to large age-adjusted core (n=86) vs not (n=431) yielded similarly encouraging results (Table 2a-b).

Conclusion: Patients with large baseline cores as measured by either NCCT or CTP may still achieve favorable outcomes with endovascular treatment. A randomized clinical trial in this patient population is warranted.

Abstract 114: Aspects versus Perfusion in the Trevo Retriever Registry: Defining the Core on the Largest Scale to Date

Background: Routine use of advanced imaging versus ASPECTS for imaging triage of endovascular thrombectomy candidates has not been evaluated on a large scale to date. Ischemic core may be defined by ASPECTS or perfusion imaging, yet these variable definitions likely reflect different pathophysiology as perfusion may fluctuate and ASPECTS lesions may be time-dependent.

Methods: The Trevo Retriever Registry was a prospective, open-label, consecutive enrollment, multicenter, international registry with more than 65 enrolling sites worldwide. The Imaging and Angiography Core Lab systematically adjudicated more than 1,500 subjects, scoring ASPECTS and separately processing perfusion imaging. Ischemic core volume on perfusion imaging was defined as rrCBF<30% (CTP) and analyzed with respect to ASPECTS.

Results: 488 subjects (68.3±14.4 years; 53.3% women; baseline NIHSS median 15 (10-19) with anterior circulation occlusions were evaluated with both ASPECTS and perfusion imaging prior to thrombectomy. Arterial occlusions included 87/487 (17.9%) ICA and 296/487 (60.8%) proximal M1 MCA, treated with thrombectomy at median 4.7 (3.3-7.9) hours from time last known well (TLKW). ASPECTS was median 8 (7-9) with ischemic core lesions of median 18 (4.9-39.2) cc. At-risk hypoperfusion (Tmax>6s) lesions were median 109.8 (62-156.9) cc. TLKW was associated with ASPECTS (r=-0.18, p<0.001) yet no time relationship was noted with either ischemic core or at-risk hypoperfusion on perfusion imaging. ASPECTS correlated modestly with perfusion imaging-derived ischemic core (r=-0.35, p<0.001) and at-risk hypoperfusion (r=-0.24, p<0.001). Post-procedure mTICI≥2b occurred in 448/488 (91.8%). Each increment in baseline ASPECTS was associated with an adjusted OR of 1.21 (95%CI (1.05-1.39), p<0.008 for good clinical outcomes (day 90 mRS 0-2), whereas the perfusion lesion volume for ischemic core and at-risk hypoperfusion did not predict outcomes.

Conclusions: Largescale, systematic evaluation of ASPECTS and perfusion imaging prior to thrombectomy reveals discrepancy in the definition of ischemic core and the prediction of clinical outcomes after revascularization. ASPECTS is time-dependent, yet reliably predicts outcomes in routine clinical practice.

Abstract 107: Real World Clinical and Radiographic Outcomes With and Without Intravenous tPA in Anterior Circulation Large Vessel Occlusion Mechanical Thrombectomy Patients Treated Within 8 Hours

Background and Aims: Intravenous tPA remains the standard of care, with MT currently indicated within 8 hours for IV tPA failures or patients with IV tPA contraindications. Whether LVO patients should receive IV tPA treatment or instead be triaged directly to MT therapy is currently unknown but greatly debated. The Trevo Registry is a real world, multi-center, international study of mechanical thrombectomy (MT) patients treated from 0-24 hours. Evaluation of the Trevo Registry clinical and procedurals outcomes of MT patients treated with or without IV tPA could provide insight into the benefit of IV tPA in MT patients. We hypothesized that in MT patients treated within 8 hours, pretreatment with intravenous tPA would lead to better clinical outcomes compared to patients who did not receive IV tPA.

Method: Consecutively enrolled patients treated within 8 hours with ICA, M1, or M2 occlusions were selected for analysis. Univariate and multivariable regressions were conducted to identify clinical and radiographic independent variables that correlate best with the dependent variable of functional outcome: mRS 0-2, with a focus on intravenous tPA treatment.

Results: A total of 1183 Trevo Registry patients (overall enrolled, n=2010) qualified for analysis, of whom 380 were not treated with IV tPA. Demographics were similar, however atrial fibrillation (46.3% vs 27.2%) and previous ischemic stroke (14.1% vs 7.5%) were higher in the no IV tPA group. The median time to treatment was similar (3.8 vs. 3.6 hrs). First pass mTICI ≥ 2B (63.6% vs 66.4%) and final revascularization (91.1% vs 92.8%) were similar between no IV tPA and IV tPA groups.Unadjusted, there were similar rates of functional outcome (90 day mRS 0-2; 60.9% vs. 62.5%). After adjustment, patients who did not receive IV-tPA had similar rates of good outcome (aOR 1.08, 95% CI [0.87-1.34]. P=0.58) as well as reduction (shift) in disability (aOR 1.08, 95% CI [0.87-1.34]. P=0.49). Safety outcomes (mortality, sICH) were similar between both groups.

Conclusion: In the Trevo Registry of MT patients treated within 8 hours, patients who did not receive IV tPA had similar endovascular and clinical outcomes as patients pretreated with IV tPA. The added benefit of IV tPA for MT patients should be further investigated.

Abstract WP31: Mechanical Thrombectomy Performs Similarly in Real-World Clinical Practise as in Randomized Trials: Nationwide Study From the Czech Republic

Background: In randomized clinical trials (RCTs) mechanical thrombectomy (MT) was proved to be a highly effective and safe treatment in acute ischemic stroke. Its efficacy and safety in routine practice needs to be documented.

Methods: Available nationwide 2016 data for the Czech Republic (CR) from SITS-TBY registry of patients with terminal internal carotid artery (ICA) and/or middle cerebral artery (MCA) occlusion were compared with data from HERMES meta-analysis. Categorical variables were compared by Pearson′s Chi-squared test, ordinal/continuous variables by Mann-Whitney test.

Results: Fourteen/15 comprehensive stroke centres reported data to SITS-TBY. From 1,053 MTs performed in the CR, 845 (80%) patients were reported to SITS-TBY. From these patients, 605 (72%) patients were involved in analyses (available outcome data in Tab.). CR and HERMES patients were comparable in: age, sex, baseline NIHSS. Occlusion locations were as follows (CR vs. HERMES): ICA 22% vs. 21% (p=0.16), M1 MCA 62% vs. 69% (p=0.004), M2 MCA 16% vs. 8% (p<0.0001). Intravenous thrombolysis was given in 76% vs. 83% patients (p=0.003). Median onset-to-reperfusion times were comparable: 232 vs. 285 min (p=0.66); median groin-to-reperfusion times were 58 vs. 63 min. Modified TICI 2b/3 was achieved in 74% (433/584) vs. 71% (390/549), p=0.24. There was no difference in percentage of PH type 2 (5.7 vs. 5.1%). Modified Rankin scale 0-2 at 3 months achieved 44% (103/235) vs. 46% (291/633) patients, p=0.57.

Conclusions: This nationwide experience on mechanical thrombectomy in acute ischemic stroke documents safety, efficacy and logistics comparable with HERMES data. Tab. Comparison on available demographic characteristics, past medical history, clinical and radiological characteristics, treatment details and outcomes in SITS-TBY versus HERMES.

Mechanical thrombectomy performs similarly in real world practice: a 2016 nationwide study from the Czech Republic

BACKGROUND

Randomized clinical trials have proven mechanical thrombectomy (MT) to be a highly effective and safe treatment in acute stroke. The purpose of this study was to compare neurothrombectomy data from the Czech Republic (CR) with data from the HERMES meta-analysis.

METHODS

Available nationwide data for the CR from 2016 from the Safe Implementation of Treatments in Stroke-Thrombectomy (SITS-TBY) registry for patients with terminal internal carotid artery (ICA) and/or middle cerebral artery (MCA) occlusions were compared with data from HERMES. CR and HERMES patients were comparable in age, sex, and baseline National Institutes of Health Stroke Scale scores.

RESULTS

From a total of 1053 MTs performed in the CR, 845 (80%) were reported in the SITS-TBY. From these, 604 (72%) were included in this study. Occlusion locations were as follows (CR vs HERMES): ICA 22% versus 21% (P=0.16), M1 MCA 62% versus 69% (P=0.004), and M2 MCA 16% versus 8% (P<0.0001). Intravenous thrombolysis was given to 76% versus 83% of patients, respectively (P=0.003). Median onset to reperfusion times were comparable: 232 versus 285 min, respectively (P=0.66). A modified Thrombolysis in Cerebral Infarction score of 2b/3 was achieved in 74% (433/584) versus 71% (390/549) of patients, respectively (OR 1.17, 95% CI 0.90-1.5, P=0.24). There was no statistically significant difference in the percentage of parenchymalhematoma type 2 (OR 1.12, 95% CI 0.66-1.90, P=0.68). A modified Rankin Scale score of 0-2 at 3 months was achieved in 48% (184/268) versus 46% (291/633) of patients, respectively (OR 0.92, 95% CI 0.71-1.18, P=0.48).

CONCLUSIONS

Data on efficacy, safety, and logistics of MT from the CR were similar to data from the HERMES collaboration.

Cirse Quality Assurance Document and Standards for Classification of Complications: The Cirse Classification System

Interventional radiology provides a wide variety of vascular, nonvascular, musculoskeletal, and oncologic minimally invasive techniques aimed at therapy or palliation of a broad spectrum of pathologic conditions. Outcome data for these techniques are globally evaluated by hospitals, insurance companies, and government agencies targeting in a high-quality health care policy, including reimbursement strategies. To analyze effectively the outcome of a technique, accurate reporting of complications is necessary. Throughout the literature, numerous classification systems for complications grading and classification have been reported. Until now, there has been no method for uniform reporting of complications both in terms of definition and grading. The purpose of this CIRSE guideline is to provide a classification system of complications based on combining outcome and severity of sequelae. The ultimate challenge will be the adoption of this system by practitioners in different countries and health economies within the European Union and beyond.

Observational cohort study of hepatic encephalopathy after transjugular intrahepatic portosystemic shunt (TIPS)

Introduction and Aim: Hepatic encephalopathy (HE) is a common complication of transjugular intrahepatic portosystemic shunting (TIPS). It is associated with a reduced quality of life and poor prognosis. The aim of this study was to compare two groups of patients who did and did not develop overt HE after TIPS. We looked for differences between these groups before TIPS.

MATERIALS AND METHODS

A study of 895 patients was conducted based on a retrospective analysis of clinical data. Data was analyzed using Fisher's exact test, Chi-square, Mann Whitney test, unpaired t-test and logistic regression. After the initial analyses, we have looked at a regression models for the factors associated with development of HE after TIPS.

RESULTS

257 (37.9%) patients developed HE after TIPS. Patients' age, pre-TIPS portal venous pressure, serum creatinine, aspartate transaminase, albumin, presence of diabetes mellitus and etiology of portal hypertension were statistically significantly associated with the occurrence of HE after TIPS (p < 0.01). However, only the age, pre-TIPS portal venous pressure, serum creatinine, presence of diabetes mellitus and etiology of portal hypertension contributed to the regression model. Patients age, serum creatinine, presence of diabetes mellitus and portal vein pressure formed the model describing development of HE after TIPS for a subgroup of patients with refractory ascites.

CONCLUSION

we have identified, using a substantial sample, several factors associated with the development of HE after TIPS. This could be helpful in further research.

Abstract WP5: The Transfer Score May Aid Decisions Whether to Transfer Patients with Large Vessel Occlusions for Endovascular Therapy

Background: While faster reperfusion with EVT leads to better outcomes in acute ischemic stroke due to large vessel occlusion (LVO), most LVO patients present to outside hospitals without EVT capability. Treating physicians are often unsure if EVT would confer benefit upon arrival to tertiary hospitals given inter-facility transfer delays.

Objective: We evaluated independent predictors of good outcome in transferred patients treated with EVT to devise a score that may assist treating physicians to make transfer and treatment decisions.

Methods: Transfer patients were analyzed in a multicenter international prospective cohort study of LVO patients treated with stent retriever thrombectomy (TREVO Registry) from 11/2013 to 4/2016. Independent factors correlating with good outcome after EVT were identified using univariate and multivariate analyses. We devised a score to identify patients with LVO at the referral facility who may benefit from EVT.

Results: Of 1000 patients enrolled, 226 were anterior circulation occlusions, transferred and treated within 0-8 hrs (Table 1). Age, stroke severity, glucose level, M2 occlusion and achieving onset to groin puncture ≤ 5 hr were independent factors associated with good outcome (Table 2). Other clinical variables were analyzed, as in ASPECTS, but were not significant. A 10 point score was devised (Table 3). Patients with a score of 0-4 had 4 times the odds of good outcome compared to a score of 5-9 (aOR 4.3, 95% CI 1.9-9.9; p <0.001). These results were maintained after adjustment for mTICI and IV-tPA (aOR 4.0, 95% CI 1.7-9.4; p <0.001). Fig 1 shows good outcome rates stratified by score points. ROC curves showed better score performance (AUC= 0.8) compared to THRIVE (AUC=0.74) and HIAT (AUC=0.69) certifying good predictability.

Conclusion: A simple transfer score may be an effective triage method to identify patients at remote facilities who may benefit from EVT upon transfer. Further validation is necessary to confirm these findings.

Abstract WMP2: Trevo 2000: Real-World Experience in the First 1247 Patients

Objective: The Trevo Registry is designed to assess real world outcomes of the Trevo Retriever in patients experiencing ischemic stroke. This is the largest prospective study for acute stroke intervention, with 1247 patients currently enrolled and 90 day outcomes in 1021 patients. The primary endpoint is revascularization status based on post-procedure TICI score and secondary endpoints include 90-day mRS, 90-day mortality, neurological deterioration at 24 hours and device/procedure related adverse events.

Methods: The study is a prospective, open-label, consecutive enrollment, multi-center, international registry of patients undergoing mechanical thrombectomy for acute stroke using the Trevo stent retriever as the initial device. Enrollment is expected to reach 2000 subjects at up to 100 sites.

Results: As of August 13, 2016 a total of 1247 patients were enrolled. The median NIHSS at admission was 16 (IQR 11-20). Most patients (66.2%) were treated at >/= 6 hours from last known normal with a median procedure time of 50 minutes (32-77). The occlusion site was M1 or M2 in 74.5%. General anesthesia was employed in 46.6% of procedures. TICI 2b or 3 revascularization was 92.8% with an average of 1.6 passes with the device. Median NIHSS at 24 hours and discharge was 6 and 4 respectively. Fifty-five percent of patients had mRS ≤2 at 3 months and the overall mortality rate was 15.4%. Patients treated after 8 hours of symptom onset had a 94.9% revascularization rate and 52.8% mRS ≤2 at 3 months. The symptomatic ICH rate was 1.2%. Patients who met the revised AHA criteria for thrombectomy were found to have 58.4% mRS 0-2 at 90 days.

Conclusions: The Trevo Retriever Registry represents the first real world data with stent retriever use in the era of clinical trials showing the overwhelming benefit of stent retrievers to treat acute ischemic stroke. Due to the fact that this data represents real world use of the Trevo Retriever, (e.g. subjects pre-stroke mRS >1 (16.5%) and those treated 6-24 hours after stroke symptoms (33.8%), this data cannot be compared to the results from recent trials with restricted eligibility criteria. Future subgroup analysis of this large cohort will help to identify areas of future research to enhance outcomes further with this treatment modality.

Abstract WMP9: Endovascular Thrombectomy Impact in the First Three “Golden” Hours

Background: Endovascular thrombectomy (EVT) substantially increases the likelihood of good outcome in acute ischemic strokes due to large vessel occlusion (LVO). Expediting EVT to achieve faster reperfusion is an important factor that correlates with good outcome. Ultra-early intervention in the first 3 “golden” hours from onset was not well characterized in recent trials.

Objective: We sought to assess the impact of early treatment within the first 3 hours on clinical outcomes in large, real life, world-wide practice.

Methods: We analyzed a multicenter international prospective cohort study of LVO patients treated with stent retriever thrombectomy (TREVO Registry) between11/2013 and 4/2016. We stratified patients based on treatment time, onset to groin puncture (GP), into 3 groups: 0-3, 3-6, >6 hrs. 90 day mRS was the primary outcome (0-2 good outcome). Logistic regression modeling was performed to evaluate the impact of treatment within the golden 3 hours on outcomes and to determine the independent factors associated with EVT initiation within 3 hours.

Results: In the 905 patients, GP occurred in: 23.1% 0-3 hrs, 44.3% 3-6 hrs and 32.6% >6 hrs. Table 1 shows similar baseline characteristics among the groups. Patient-level predictors of treatment within 3 hrs were age (aOR 1.1 per decade of age ≥18) and good ASPECTS (aOR 1.2 per point). No hospital-level predictors of early treatment were found. Patients treated within 3 hrs have a higher likelihood of good outcome as compared to those treated >3 hrs (aOR 2.0, 95% CI 1.4-2.9; p <0.001) after adjustment for age, NIHSS, IV tPA and mTICI ≥2b (Table 2). No differences were found in mortality and sICH. Treatment in the golden hours had the highest impact on excellent outcome rates (mRS 0-1) (Fig 1).

Conclusion: Early thrombectomy of LVO strokes, within the first three hours provides the highest impact compared with later time windows. Streamlining processes to deliver rapid intervention within 3 hours would improve clinical outcomes.

Abstract TP20: Uncertainties of Endovascular Therapy Outside the AHA Guidelines

Background: The efficacy of endovascular therapy (EVT) in randomized clinical trials (RCTs) for acute strokes due to large vessel occlusion (LVO) led to AHA guidelines recommending EVT as standard of care for selected patients. However, many conditions were under-represented in the RCTs: ASPECTS <6, age ≥80 yo, NIHSS <6, onset to treatment >6 hrs and M2/ distal/ posterior circulation occlusions.

Objective: We evaluated EVT outcomes in these populations compared to counterparts represented in the RCTs.

Methods: A large multicenter international prospective cohort study of LVO patients treated with stent retriever thrombectomy (TREVO Registry) between 11/2013 and 4/2016 was analyzed. 90 day mRS was the primary outcome (0-2 good outcome). Multivariate logistic regression modeling was employed to evaluate EVT impact in the different groups.

Results: Of 1000 patients, 81 had NIHSS <6 and 81.5% of those achieved a good outcome (aOR 3.6, 95% CI 1.9-6.8; p< 0.001 compared with NIHSS ≥6) (Table 1). Over 80 yo, however, had low odds of independence (aOR 0.3, 95% CI 0.2-0.5; p <0.001 compared with <80 yo). Among 212 patients treated >6 hrs, 51% had a good outcome (aOR 0.78, 95% CI 0.55-1.1; p =0.17) compared to ≤6 hrs. Nearly half of patients with ASPECTS <6 (3-5) had a good outcome. Fig 1 illustrates mRS distributions stratified by the different subgroups. There were low rates of sICH for treated patients with NIHSS<6, age≥80, ASPECTS <6 or treatment >6 hrs. Fig 2 demonstrates the likelihood of good outcome by clot location. M2 and distal occlusions had the highest good outcome probabilities while proximal ICAs had the lowest (48.1%). More than half of vertebrobasilar patients achieved independence (54.8%).

Conclusion: While effectiveness cannot be determined in the absence of medically treated controls, our analyses of real world data show several groups outside AHA guidelines may benefit from EVT. In particular, further study is needed to examine EVT benefits for mild stroke and M2 occlusions.

Abstract WMP11: Joint Commission Certified Stroke Centers Treat More Severe Strokes with Faster Procedure Times Compared to Non-joint Commission Certified Stroke Centers in the Trevo Registry

Introduction: Endovascular stroke therapy has become the gold standard treatment for large vessel occlusion. The Joint Commission has certified hospitals as Comprehensive stroke centers (JCCSC) based on rigorous standards in the hopes of identifying centers of excellence. We sought to determine if JCCSC have faster door to reperfusion times compared to non-JCCSC.

Methods: The TREVO registry is a multicenter international real world registry assessing angiographic and clinical outcomes with the Trevo device being used in the first pass. We defined a CSC as certified by the Joint Commission as of July 1, 2016. Demographic information, times within the hospital, angiographic results and clinical outcomes were analyzed between the JCCSC and non-JCCSC institutions.

Results: A total of 507 patients (329 JCCSC, 178 non-JCCSC) have completed data in the Trevo registry to date. There are a higher proportion of patients with ASPECTS < 7 being treated at JCCSC vs. non-JCCSC (8.8% vs. 0.0%, p<0.02). There were no differences in outcomes, reperfusion rates or symptomatic hemorrhage rates between the two groups. Demographics were similar except patients treated at a JCCSC had a higher median NIHSS [17 vs. 15, p<0.003] compared to the non-JCCSC group. Median (IQR) door to puncture times did not differ between the two groups [85(57-132) vs. 91(59-137), p<0.96], but patients treated at a JCCSC had lower mean angiographic procedure times [59 ± 34 minutes vs. 66±44 minutes, p<0.05]. The analysis did not change when we looked at the subset of patients who were not transferred with anterior circulation strokes less than 8 hours from onset.

Conclusions: Patients treated at a JCCSC had faster procedural times, without faster door to procedure times when compared to non-JCCSC centers. Outcomes were no different, due to imbalances in stroke severity at baseline and a higher proportion of patients with ASPECTS < 7 being treated.

Abstract 37: ASPECTS and Stratified Outcomes After Endovascular Therapy in the Trevo Retriever Registry: Benefit in Low ASPECTS

Background: Most endovascular stroke therapy studies and subsequent guidelines restrict intervention based on ASPECTS. A wide range of ASPECTS scores may be encountered in practice and individual patient benefit may be realized even at low ASPECTS. We examined large-scale data on outcomes after endovascular therapy, stratified by baseline ASPECTS in the Trevo Retriever Registry.

Methods: The independent Imaging Core Lab of the Trevo Retriever Registry prospectively determines ASPECTS on baseline imaging acquired immediately prior to endovascular thrombectomy. ASPECTS scores and regional involvement were analyzed with respect to site of arterial occlusion, effect of time from symptom onset, co-morbidities and clinical outcomes, based on ASPECTS strata.

Results: Baseline ASPECTS data was reviewed by the Imaging Core Lab in 426 subjects with anterior circulation stroke enrolled in the Trevo Retriever Registry, as of July 2016. Mean age was 68.8 ± 13.7 yrs, with 20.9% > 80 years old. Baseline NIHSS was median 15.0 (10.0, 19.0). Onset to CT was median 3.8 (1.5, 9.0) hrs, with median ASPECTS of 8.0 (7.0, 9.0), ranging from 3-10. Baseline ASPECTS 0-7 occurred in 118/426 (27.7%) subjects, including 39.0% of ICA, 27.1% M1 and 16.9% M2/3 arterial occlusions at angiography. Baseline clinical variables predicting ASPECTS included age and NIHSS, whereas the ASPECTS score was mildly associated with final TICI2C reperfusion (r=0.24, p<0.001). Subsequent symptomatic ICH was 1.7% with baseline ASPECTS 0-7 versus 2.0% with ASPECTS 8-10. The distribution of mRS at 90 days based on individual ASPECTS strata from 10 to 3 revealed a trend to worse outcomes with lower ASPECTS, yet good outcomes (mRS 0-2) were 60.7% (ASPECTS 10), 55.3% (9), 60.2% (8), 54.9% (7), 55.1% (3-6).

Conclusions: Discrete ASPECTS strata may influence outcomes of endovascular therapy conducted in routine practice around the world, yet individuals with low ASPECTS may still achieve reasonable outcomes.

Abstract WP6: Real-World Data on Reperfusion: Evidence of Good Outcomes in the International Trevo Retriever Registry

Background: Endovascular thrombectomy trials established efficacy in acute ischemic stroke, yet real-world data on device effectiveness is warranted. Core lab adjudication of angiography is required to validate reperfusion, providing evidence and detailed data beyond randomized, controlled trials. We report the largest endovascular therapy registry data linking independent core lab data on reperfusion with clinical outcomes.

Methods: The Trevo Retriever Registry is a prospective, open-label, consecutive enrollment, multicenter, international registry with more than 65 enrolling sites worldwide. An independent Imaging Core Lab, blind to all other data, evaluates the angiography with a battery of various TICI scores (mTICI, oTICI, oTICI2C) to define reperfusion. Statistical analyses examined TICI reperfusion and association with clinical outcomes considering expansive data collected in the registry.

Results: 506 enrolled subjects (mean age 68.2 ± 14.2 yrs; 53% female) had core lab adjudicated angiography as of July 2016, including 21.5% > 80 years old. Baseline NIHSS was median 15.0 (9.0, 20.0) with time from onset to CT of median 4.0 (1.7, 9.7) hrs. Core lab adjudicated arterial occlusion sites were: 53% M1, 24% ICA, 16% M2, 4% Basilar and 2% other. Time to reperfusion (oTICI ≥ 2A) was median 30.0 (19.0, 42.0) min. Core lab adjudicated revascularization was mTICI ≥ 2B in 90.4% (95%CI 87.4, 92.9), oTICI ≥ 2B in 82.3% (95%CI 78.6, 85.6) and oTICI2C ≥ 2C in 45.0% (95%CI 40.5, 49.6). mRS of 0-2 at 90 days was achieved in 57.3% (95%CI 52.5, 62.1). Extensive clinical, laboratory and stroke workflow variables were considered, yet only male sex (OR 0.62 (95% CI 0.38, 0.99) was an independent predictor of successful reperfusion (oTICI ≥ 2B) while age (OR 0.96 (95% CI 0.94, 0.97), NIHSS (OR 0.91 (95% CI 0.88, 0.94) and diabetes (OR 0.54 (95% CI 0.33, 0.88) predicted mRS 0-2 at 90 days.

Conclusions: Proven reperfusion rates after endovascular stroke therapy excel in the real-world translation of thrombectomy devices around the globe, leading to good outcomes after stroke.

Abstract WP4: Transfer Patients and Patients Presenting Directly to Endovascular Capable Centers Achieve Similar Good Outcome Rates with Endovascular Therapy

Background: While endovascular therapy (EVT) is effective for large vessel occlusions (LVO), most patients present to hospitals without EVT capability and are transferred for intervention, delaying treatment.

Objective: We evaluated outcomes in LVO patients treated with thrombectomy who were transferred compared to those presenting directly to EVT facilities.

Methods: In a large multicenter international prospective cohort study of LVO patients treated with stent retriever thrombectomy (TREVO Registry), patients were stratified by initial presentation into transferred (TNS) vs direct (DIR). 90 day mRS was the primary outcome (0-1 excellent, 0-2 good outcomes); sICH and reperfusion by mTICI were secondary outcomes. Outcomes were compared in the 2 groups (0-8 hrs onset to groin puncture (GP) then in time matched 3-8 hrs subgroups for validation). Logistic regression identified independent predictors of good outcome in TNS patients.

Results: We identified 540 patients (230 TNS; 310 DIR) (Fig 1). TNS patients were younger and had longer onset to GP times (4.6 vs 3.1 hrs; p <0.001) (Table 1). DIR achieved higher excellent outcomes (50.4 vs 38.7%; p <0.001) (Table 2). There were no significant differences in good clinical outcomes (61 DIR vs 57.4% TNS, OR 0.90, 95% CI 0.63-1.27; p =0.4) (Fig 2) and no difference in the time matched 3-8 hrs subgroups (59.2% DIR vs 56.3% TNS, p =0.6). Fig 3 plots good outcome probabilities over time, showing similar confidence interval bands. Younger age (OR 0.95), lower NIHSS (OR 0.90), glucose level < 170 mg/dL (OR 2.4), distal clot location (M2) (OR 1.7), excellent reperfusion (mTICI≥2b) (OR 2) and time to GP <5 hrs (OR 1.6) were independent predictors of good outcome in TNS patients.

Conclusion: While excellent outcomes were higher in directly-presenting patients, EVT-treated transfers may achieve similar good outcomes. The association between earlier EVT after transfer and better outcomes emphasizes the need to streamline the transfer process.