Showing papers by "Albert J Yoo published in 2021"

Association between clot composition and stroke origin in mechanical thrombectomy patients: Analysis of the Stroke Thromboembolism Registry of Imaging and Pathology

Abstract: Background We retrospectively evaluated the composition of retrieved clots from ischemic stroke patients to study the association between histological composition and stroke etiology Methods Consecutive patients enrolled in the Stroke Thromboembolism Registry of Imaging and Pathology (STRIP) were included in this study. All patients underwent mechanical thrombectomy and retrieved clots were sent to a central core lab for processing. Histological analysis was performed using martius scarlet blue (MSB) staining, and quantification for red blood cells (RBCs), white blood cells (WBCs), fibrin and platelets was performed using Orbit Image Software. A Wilcoxon test was used for continuous variables and χ2 test for categorical variables. Results 1350 patients were included in this study. The overall rate of Thrombolysis In Cerebral Infarction (TICI) 2c/3 was 68%. 501 patients received tissue plasminogen activator (tPA) (37%). 267 patients (20%) had a large artery atherosclerosis (LAA) source, 662 (49%) a cardioembolic (CE) source, 301 (22%) were cryptogenic, and the remainder had other identifiable sources including hypercoagulable state or dissection. LAA thrombi had a higher mean RBC density (46±23% vs 42±22%, p=0.01) and a lower platelet density (24±18% vs 27±18%, p=0.03) than CE thrombi. Clots from dissection patients had the highest mean RBC density (50±24%) while clots from patients with a hypercoagulable state had the lowest mean RBC density (26±21%). Conclusions Our study found statistically significant but clinically insignificant differences between clots of CE and LAA etiologies. Future studies should emphasize molecular, proteomic and immunohistochemical characteristics to determine links between clot composition and etiology.

Select wisely: the ethical challenge of defining large core with perfusion in the early time window.

Abstract: The pivotal stroke trials published in 2015 provided indisputable evidence of the benefit of thrombectomy in early window (0–6 hours) patients with anterior circulation emergent large vessel occlusion (ELVO) and small infarcts on non-contrast CT (NCCT), measured by ASPECTS 6–10.1–5 Since then, endovascular treatment of this population has been standard guideline-based care.6 Efforts, similar to the late window trials,7 8 are now directed at further expanding thrombectomy indications. Five trials are underway investigating the role of thrombectomy in patients with ELVO with ASPECTS <6, the 'large core' population for whom formal level I evidence is lacking (TENSION (NCT03094715); IN EXTREMIS-LASTE (NCT03811769); TESLA (NCT03805308); SELECT 2 (NCT03876457); and RESCUE-Japan LIMIT (NCT03702413)). Of these studies, all define large core using ASPECTS alone, except for one (SELECT 2). This study defines large core using ASPECTS or CT perfusion (CTP), and in doing so includes patients with poor NCCT ASPECTS (score <6) and also those with NCCT ASPECTS 6–10 with CTP-estimated ischemic core volumes ≥50 mL. Because the pivotal trials show unequivocally that patients with ASPECTS 6–10 and ELVO benefit from endovascular treatment in the 0–6-hour time window, we believe that this subgroup in SELECT 2 withholds proven class I treatment from eligible patients, raising concern for patient harm. As its name implies, CTP provides a measure of cerebral perfusion or, in the case of stroke, the strength of the collateral circulation.9 Even if one accepts the proposition that CTP can provide an accurate measure of cerebral blood flow (CBF),10 basic physiologic experiments and clinical studies have demonstrated that the progression from reversible ischemia to infarction is dependent on both CBF and the duration of ischemia.11–13 Taken together, the idea that one can accurately identify the region of irreversible injury (the core) from a threshold applied to a single snapshot …

Predictors of poor outcome despite successful endovascular treatment for ischemic stroke: results from the MR CLEAN Registry

Abstract: Background Approximately one-third of patients with ischemic stroke treated with endovascular treatment do not recover to functional independence despite rapid and successful recanalization. We aimed to quantify the importance of predictors of poor functional outcome despite successful reperfusion. Methods We analyzed patients from the MR CLEAN Registry between March 2014 and November 2017 with successful reperfusion (extended Thrombolysis In Cerebral Infarction ≥2B). First, predictors were selected based on expert opinion and were clustered according to acquisition over time (ie, baseline patient factors, imaging factors, treatment factors, and postprocedural factors). Second, several models were constructed to predict 90-day functional outcome (modified Rankin Scale (mRS)). The relative importance of individual predictors in the most extensive model was expressed by the proportion of unique added χ2 to the model of that individual predictor. Results Of 3180 patients, 1913 (60%) had successful reperfusion. Of these 1913 patients, 1046 (55%) were functionally dependent at 90 days (mRS >2). The most important predictors for mRS were baseline patient factors (ie, pre-stroke mRS, added χ2 0.16; National Institutes of Health Stroke Scale score at baseline, added χ2 0.12; age, added χ2 0.10), and postprocedural factors (ie, symptomatic intracranial hemorrhage (sICH), added χ2 0.12; pneumonia, added χ2 0.09). The probability of functional independence for a typical stroke patient with sICH was 54% (95% CI 36% to 72%) lower compared with no sICH, and 21% (95% CI 4% to 38%) for pneumonia compared with no pneumonia. Conclusion Baseline patient factors and postprocedural adverse events are important predictors of poor functional outcome in successfully reperfused patients with ischemic stroke. This implies that prevention of postprocedural adverse events has the greatest potential to further improve outcomes in these patients.

Health economic impact of first-pass success among patients with acute ischemic stroke treated with mechanical thrombectomy: a United States and European perspective

Abstract: Background First-pass effect (FPE), restoring complete or near complete reperfusion (modified Thrombolysis in Cerebral Infarction (mTICI) 2c-3) in a single pass, is an independent predictor for good functional outcomes in the endovascular treatment of acute ischemic stroke. The economic implications of achieving FPE have not been assessed. Objective To assess the economic impact of achieving complete or near complete reperfusion after the first pass. Methods Post hoc analyses were conducted using ARISE II study data. The target population consisted of patients in whom mTICI 2c–3 was achieved, stratified into two groups: (1) mTICI 2c–3 achieved after the first pass (FPE group) or (2) after multiple passes (non-FPE group). Baseline characteristics, clinical outcomes, and healthcare resource use were compared between groups. Costs from peer-reviewed literature were applied to assess cost consequences from the perspectives of the United States (USA), France, Germany, Italy, Spain, Sweden, and United Kingdom (UK). Results Among patients who achieved mTICI 2c–3 (n=172), FPE was achieved in 53% (n=91). A higher proportion of patients in the FPE group reached good functional outcomes (90-day modified Rankin Scale score 0–2 80.46% vs 61.04%, p Conclusions FPE resulted in improved clinical outcomes, translating into lower healthcare resource use and lower estimated costs.

Histological evaluation of acute ischemic stroke thrombi may indicate the occurrence of vessel wall injury during mechanical thrombectomy.

Abstract: Background Several animal studies have demonstrated that mechanical thrombectomy (MT) for acute ischemic stroke (AIS) may cause vessel wall injury (VWI). However, the histological changes in human cerebral arteries following MT are difficult to determine. Objective To investigate the occurrence of VWI during MT by histological and immunohistochemical evaluation of AIS clots. Methods As part of the multicenter STRIP registry, 277 clots from 237 patients were analyzed using Martius Scarlett Blue stain and immunohistochemistry for CD34 (endothelial cells) and smooth muscle actin (smooth muscle cells). Results MT devices used were aspiration catheters (100 cases), stentriever (101 cases), and both (36 cases). VWI was found in 33/277 clots (12%). There was no significant correlation between VWI and MT device. The degree of damage varied from grade I (mild intimal damage, 24 clots), to grade II (relevant intimal and subintimal damage, 3 clots), and III (severe injury, 6 clots). VWI clots contained significantly more erythrocytes (p=0.006*) and less platelets/other (p=0.005*) than non-VWI clots suggesting soft thrombus material. Thrombolysis correlated with a lower rate of VWI (p=0.04*). VWI cases showed a significantly higher number of passes (2 [1–4] vs 1 [1–3], p=0.028*) and poorer recanalization outcome (p=0.01*) than cases without VWI. Conclusions Histological markers of VWI were present in 12% of AIS thrombi, suggesting that VWI might be related to MT. VWI was associated with soft thrombus consistency, higher number of passes and poorer revascularization outcome. There was no significant correlation between VWI and MT device.

Benchmarking the Extent and Speed of Reperfusion: First Pass TICI 2c-3 Is a Preferred Endovascular Reperfusion Endpoint.

Abstract: Background and Purpose: End-of-procedure substantial reperfusion [modified Treatment in Cerebral Ischemia (mTICI) 2b-3], the leading endpoint for thrombectomy studies, has several limitations including a ceiling effect, with recent achieved rates of ~90%. We aimed to identify a more optimal definition of angiographic success along two dimensions: (1) the extent of tissue reperfusion, and (2) the speed of revascularization. Methods: Core-lab adjudicated TICI scores for the first three passes of EmboTrap and the final all-procedures result were analyzed in the ARISE II multicenter study. The clinical impact of extent of reperfusion and speed of reperfusion (first-pass vs. later-pass) were evaluated. Clinical outcomes included 90-day functional independence [modified Rankin Scale (mRS) 0-2], 90-day freedom-from-disability (mRS 0-1), and dramatic early improvement [24-h National Institutes of Health Stroke Scale (NIHSS) improvement ≥ 8 points]. Results: Among 161 ARISE II subjects with ICA or MCA M1 occlusions, reperfusion results at procedure end showed substantial reperfusion in 149 (92.5%), excellent reperfusion in 121 (75.2%), and complete reperfusion in 79 (49.1%). Reperfusion rates on first pass were substantial in 81 (50.3%), excellent reperfusion in 62 (38.5%), and complete reperfusion in 44 (27.3%). First-pass excellent reperfusion (first-pass TICI 2c-3) had the greatest nominal predictive value for 90-day mRS 0-2 (sensitivity 58.5%, specificity 68.6%). There was a progressive worsening of outcomes with each additional pass required to achieve TICI 2c-3. Conclusions: First-pass excellent reperfusion (TICI 2c-3), reflecting rapid achievement of extensive reperfusion, is the technical revascularization endpoint that best predicted functional independence in this international multicenter trial and is an attractive candidate for a lead angiographic endpoint for future trials. Clinical Trial Registration: http://www.clinicaltrials.gov, identifier NCT02488915.

Cyclical aspiration using a novel mechanical thrombectomy device is associated with a high TICI 3 first pass effect in large-vessel strokes.

Abstract: Background and purpose Complete reperfusion (TICI 3) after the first thrombectomy attempt or first pass effect (FPE) is associated with best clinical outcomes in large-vessel occlusion (LVO) acute ischemic stroke. While endovascular therapy techniques have improved substantially, FPE remains low (24-30%), and new methods to improve reperfusion efficiency are needed. Methods In a prospective observational cohort study, 40 consecutive patients underwent cyclical aspiration thrombectomy using CLEARTM Aspiration System (Insera Therapeutics Inc., Dallas, TX). Primary outcome included FPE with complete/near-complete reperfusion (TICI 2c/3 FPE). Secondary outcomes included early neurological improvement measured by the National Institute of Health Stroke Scale (NIHSS), safety outcomes, and functional outcomes using modified Rankin Scale (mRS). Outcomes were compared against published historical controls. Results Among 38 patients who met criteria for LVO, median age was 75 (range 31-96). FPE was high (TICI 3: 26/38 [68%], TICI 2c/3: 29/38 [76%]). Among anterior circulation strokes, core lab-adjudicated FPE remained high (TICI 3: 17/29 [59%], TICI 2c/3: 20/29 [69%]), with excellent final successful revascularization results (Final TICI 3: 24/29 [83%], Final TICI 2c/3: 27/29 [93%]). FPE in the CLEAR-1 cohort was significantly higher compared to FPE using existing devices (meta-analysis) from historical controls (TICI 2c/3: 76% vs. 28%, p = 0.0001). High rates of early neurological improvement were observed (delta NIHSS≥4: 35/38 [92.1%]; delta NIHSS≥10: 27/38 [71%]). Similarly, high rates of good functional outcomes (mRS 0-2: 32/38 [84%]) and low mortality (2/38 [5%]) were observed. Conclusion Cyclical aspiration using the CLEARTM Aspiration System is safe, effective, and achieved a high TICI 3 FPE for large-vessel strokes.

The Role of Edema in Subacute Lesion Progression After Treatment of Acute Ischemic Stroke.

Abstract: Background: Ischemic lesions commonly continue to progress even days after treatment, and this lesion growth is associated with unfavorable functional outcome in acute ischemic stroke patients. The aim of this study is to elucidate the role of edema in subacute lesion progression and its influence on unfavorable functional outcome by quantifying net water uptake. Methods: We included all 187 patients from the MR CLEAN trial who had high quality follow-up non-contrast CT at 24 h and 1 week. Using a CT densitometry-based method to calculate the net water uptake, we differentiated total ischemic lesion volume (TILV) into edema volume (EV) and edema-corrected infarct volume (ecIV). We calculated these volumes at 24 h and 1 week after stroke and determined their progression in the subacute period. We assessed the effect of 24-h lesion characteristics on EV and ecIV progression. We evaluated the influence of edema and edema-corrected infarct progression on favorable functional outcome after 90 days (modified Rankin Scale: 0-2) after correcting for potential confounders. Lastly, we compared these volumes between subgroups of patients with and without successful recanalization using the Mann-Whitney U-test. Results: Median TILV increased from 37 (IQR: 18-81) ml to 68 (IQR: 30-130) ml between 24 h and 1 week after stroke, while the net water uptake increased from 22 (IQR: 16-26)% to 27 (IQR: 22-32)%. The TILV progression of 20 (8.8-40) ml was mostly caused by ecIV with a median increase of 12 (2.4-21) ml vs. 6.5 (2.7-15) ml of EV progression. Larger TILV, EV, and ecIV volumes at 24 h were all associated with more edema and lesion progression. Edema progression was associated with unfavorable functional outcome [aOR: 0.53 (0.28-0.94) per 10 ml; p-value: 0.05], while edema-corrected infarct progression showed a similar, non-significant association [aOR: 0.80 (0.62-0.99); p-value: 0.06]. Lastly, edema progression was larger in patients without successful recanalization, whereas ecIV progression was comparable between the subgroups. Conclusion: EV increases in evolving ischemic lesions in the period between 1 day and 1 week after acute ischemic stroke. This progression is larger in patients without successful recanalization and is associated with unfavorable functional outcome. However, the extent of edema cannot explain the total expansion of ischemic lesions since edema-corrected infarct progression is larger than the edema progression.

Per pass analysis of thrombus composition retrieved by mechanical thrombectomy

Abstract: Background and aimMechanical thrombectomy (MT) for large vessel occlusion often requires multiple passes to retrieve the entire thrombus load. In this multi-institutional study we sought to examine...

Endovascular Treatment of Acute Ischemic Stroke With the Penumbra System in Routine Practice: COMPLETE Registry Results.

Abstract: Background and Purpose: The purpose of the COMPLETE (International Acute Ischemic Stroke Registry With the Penumbra System Aspiration Including the 3D Revascularization Device) registry was to eval...

qTICI: Quantitative assessment of brain tissue reperfusion on digital subtraction angiograms of acute ischemic stroke patients:

Abstract: Background: The Thrombolysis in Cerebral Infarction (TICI) scale is an important outcome measure to evaluate the quality of endovascular stroke therapy. The TICI scale is ordinal and observer-dependent, which may result in suboptimal prediction of patient outcome and inconsistent reperfusion grading. Aims: We present a semi-automated quantitative reperfusion measure (quantified TICI (qTICI)) using image processing techniques based on the TICI methodology. Methods: We included patients with an intracranial proximal large vessel occlusion with complete, good quality runs of anteroposterior and lateral digital subtraction angiography from the MR CLEAN Registry. For each vessel occlusion, we identified the target downstream territory and automatically segmented the reperfused area in the target downstream territory on final digital subtraction angiography. qTICI was defined as the percentage of reperfused area in target downstream territory. The value of qTICI and extended TICI (eTICI) in predicting favorable functional outcome (modified Rankin Scale 0–2) was compared using area under receiver operating characteristics curve and binary logistic regression analysis unadjusted and adjusted for known prognostic factors. Results: In total, 408 patients with M1 or internal carotid artery occlusion were included. The median qTICI was 78 (interquartile range 58–88) and 215 patients (53%) had an eTICI of 2C or higher. qTICI was comparable to eTICI in predicting favorable outcome with area under receiver operating characteristics curve of 0.63 vs. 0.62 (P = 0.8) and 0.87 vs. 0.86 (P = 0.87), for the unadjusted and adjusted analysis, respectively. In the adjusted regression analyses, both qTICI and eTICI were independently associated with functional outcome. Conclusion: qTICI provides a quantitative measure of reperfusion with similar prognostic value for functional outcome to eTICI score.

Posttreatment Ischemic Lesion Evolution Is Associated With Reduced Favorable Functional Outcome in Patients With Stroke.

Abstract: Background and Purpose: Ischemic lesion volume can increase even 24 hours after onset of an acute ischemic stroke. In this study, we investigated the association of lesion evolution with functional...

The SMART Registry: Long-Term Results on the Utility of the Penumbra SMART COIL System for Treatment of Intracranial Aneurysms and Other Malformations.

Abstract: Introduction: Penumbra SMART COIL® (SMART) System is a novel generation embolic coil with varying stiffness. The study purpose was to report real-world usage of the SMART System in patients with intracranial aneurysms (ICA) and non-aneurysm vascular lesions. Materials and Methods: The SMART Registry is a post-market, prospective, multicenter registry requiring ≥75% Penumbra Coils, including SMART, PC400, and/or POD coils. The primary efficacy endpoint was retreatment rate at 1-year and the primary safety endpoint was the procedural device-related serious adverse event rate. Results: Between June 2016 and August 2018, 995 patients (mean age 59.6 years, 72.1% female) were enrolled at 68 sites in the U.S. and Canada. Target lesions were intracranial aneurysms in 91.0% of patients; 63.5% were wide-neck and 31.8% were ruptured. Adjunctive devices were used in 55.2% of patients. Mean packing density was 32.3%. Procedural device-related serious adverse events occurred in 2.6% of patients. The rate of immediate post-procedure adequate occlusion was 97.1% in aneurysms and the rate of complete occlusion was 85.2% in non-aneurysms. At 1-year, the retreatment rate was 6.8%, Raymond Roy Occlusion Classification (RROC) I or II was 90.0% for aneurysms, and Modified Rankin Scale (mRS) 0-2 was achieved in 83.1% of all patients. Predictors of 1-year for RROC III or retreatment (incomplete occlusion) were rupture status (P < 0.0001), balloon-assisted coiling (P = 0.0354), aneurysm size (P = 0.0071), and RROC III immediate post-procedure (P = 0.0086) in a model that also included bifurcation aneurysm (P = 0.7788). Predictors of aneurysm retreatment at 1-year was rupture status (P < 0.0001). Conclusions: Lesions treated with SMART System coils achieved low long-term retreatment rates. Clinical Trial Registration: https://www.clinicaltrials.gov/, identifier NCT02729740.

Prevalence, Predictors, and Outcomes of Prolonged Mechanical Ventilation After Endovascular Stroke Therapy.

Abstract: To investigate the rates, predictors, and outcomes of prolonged mechanical ventilation (≥ 96 h) following endovascular treatment (EVT) of ischemic stroke. Hospitalizations with acute ischemic stroke and EVT were identified using validated codes in the National Inpatient Sample (2010–2015). The primary outcome was prolonged mechanical ventilation defined as ventilation ≥ 96 consecutive hours. We compared hospitalizations involving prolonged ventilation following EVT with those that did not involve prolonged ventilation. Propensity score matching was used to adjust for differences between groups. Clinical predictors of prolonged ventilation were assessed using multivariable conditional logistic regression analyses. Among the 34,184 hospitalizations with EVT, 5087 (14.9%) required prolonged mechanical ventilation. There was a decline in overall intubation and prolonged ventilation during the study period. On multivariable analysis, history of heart failure [OR 1.28 (95% CI 1.05–1.57)] and diabetes [OR 1.22 (95% CI 1–1.50)] was independent predictors of prolonged ventilation following EVT. In a sensitivity analysis of anterior circulation stroke only, heart failure [OR 1.3 (95% CI 1.10–1.61)], diabetes [OR 1.25 (95% CI 1.01–1.57)], and chronic lung disease [OR 1.31 (95% CI 1.03–1.66)] were independent predictors of prolonged ventilation. The weighted proportions of in-hospital mortality, post-procedural shock, acute renal failure, and intracerebral hemorrhage were higher in the prolonged ventilation group. Among a nationally representative sample of hospitalizations, nearly one-in-six patients had prolonged mechanical ventilation after EVT. Heart failure and diabetes were significantly associated with prolonged mechanical ventilation following EVT. Prolonged ventilation was associated with significant increase in in-hospital mortality and morbidity.

Is a picture-perfect thrombectomy necessary in acute ischemic stroke?

Abstract: Background The benefit of complete reperfusion (modified Thrombolysis in Cerebral Infarction (mTICI) 3) over near-complete reperfusion (≥90%, mTICI 2c) remains unclear. The goal of this study is to compare clinical outcomes between mechanical thrombectomy (MT)-treated stroke patients with mTICI 2c versus 3. Methods This is a retrospective study from the Stroke Thrombectomy and Aneurysm Registry (STAR) comprising 33 centers. Adults with anterior circulation arterial vessel occlusion who underwent MT yielding mTICI 2c or mTICI 3 reperfusion were included. Patients were categorized based on reperfusion grade achieved. Primary outcome was modified Rankin Scale (mRS) 0–2 at 90 days. Secondary outcomes were mRS scores at discharge and 90 days, National Institutes of Health Stroke Scale score at discharge, procedure-related complications, and symptomatic intracerebral hemorrhage. Results The unmatched mTICI 2c and mTICI 3 cohorts comprised 519 and 1923 patients, respectively. There was no difference in primary (42.4% vs 45.1%; p=0.264) or secondary outcomes between the unmatched cohorts. Reperfusion status (mTICI 2c vs 3) was also not predictive of the primary outcome in non-imputed and imputed multivariable models. The matched cohorts each comprised 191 patients. Primary (39.8% vs 47.6%; p=0.122) and secondary outcomes were also similar between the matched cohorts, except the 90-day mRS which was lower in the matched mTICI 3 cohort (p=0.049). There were increased odds of the primary outcome with mTICI 3 in patients with baseline mRS ≥2 (36% vs 7.7%; p=0.011; pinteraction=0.014) and a history of stroke (42.3% vs 15.4%; p=0.027; pinteraction=0.041). Conclusions Complete and near-complete reperfusion after MT appear to confer comparable outcomes in patients with acute stroke.

Periprocedural safety of saccular aneurysm embolization with the Penumbra SMART Coil System: a SMART registry subset analysis.

Abstract: Background Using data from the SMART registry, we report on periprocedural safety of the Penumbra SMART Coil System for endovascular coil embolization of saccular intracranial aneurysms. Methods The SMART registry was a prospective, multi-center registry of site standard of care endovascular coiling procedures performed using at least 75% Penumbra SMART Coil, PC400, and/or POD coils. This subset analysis reports on the periprocedural safety outcomes of the saccular intracranial aneurysm cohort. Predictors of rupture/re-rupture or perforation (RRP), thromboembolic complications, and device- or procedure-related adverse events (AEs) were determined in univariate and multivariate analysis. Results Between June 2016 and August 2018, 851 saccular aneurysm patients (31.0%, 264/851 ruptured) were enrolled across 66 North American centers. Clinically significant (ie, a serious adverse event) RRP occurred in 2.0% (17/851) of cases – 1.9% (5/264) for the ruptured cohort and 2.0% (12/587) for the un-ruptured cohort. Clinically significant thromboembolic events occurred in 3.1% (26/851) of cases – 5.3% (14/264) for the ruptured cohort and 2.0% (12/587) for the un-ruptured cohort. Multivariate predictors of periprocedural RRP were increased packing density and adjunctive treatment with a balloon. For periprocedural thromboembolic events, multivariate predictors were bifurcation location and ruptured status. For device- or procedure-related AEs, multivariate predictors were bifurcation location and adjunctive treatment with stent or balloon. Conclusion The low rates of thromboembolic complications and RRP events demonstrate the adequate safety profile of the SMART Coil System to treat cerebral aneurysms in routine clinical practice. Trial registration number NCT02729740.

P-006 Update on the reperfusion with cooling in cerebral acute ischemia II (RECCLAIM II) trial

Abstract: Introduction Endovascular therapy for large vessel occlusion has become the standard of care for appropriate patients treated under 24 hours from onset. Despite being superior to standard medical management, roughly 50% of patients still do not achieve independent neurological functioning. Therapeutic hypothermia (TH) impacts multiple pathways to provide neuroprotection in stroke by lower metabolic demand. Prior trials with TH may have failed due to inconsistent reperfusion therapies at that time. The RECCLAIM II study was designed to test if the addition of TH to endovascular reperfusion is feasible and safe. We intend to provide an update on the progress and status of the study as enrollment continues. Methods Prospective, multi-center, randomized-controlled study with a target enrollment of 120 patients to assess the safety and feasibility to achieve rapid hypothermia to under 34 degrees C with the ZOLL Intravascular Proteus system prior to achieving reperfusion. Cooling will be maintained for 6 hours with rewarming to 36.5-37 degrees C over the next 3-6 hours. CT studies will be assessed for hemorrhagic complications 24 hours post-procedure and 90-day blinded outcomes will be obtained on each patient. Up to ten centers will enroll up to 120 patients for the study. Each center will perform 4 Roll-in cases prior to entering the randomization phase. The primary feasibility endpoint is that the majority of patients will achieve a temperature of 34 degrees C within one hour of arterial puncture without significant delays to reperfusion when comparing the control and treatment arms. The secondary endpoints include rates of hemorrhage and clinical outcomes in both arms. Results A total of 30 patients have been enrolled to date. Times for each procedure, ability to achieve rapid hypothermia, 90 day blinded Modified Rankin, and core lab adjudicated hemorrhagic complication rates will be evaluated. The DMC will review significant adverse events and mortalities. Workflow time metrics will be assessed for both arms to assess for how quickly TH can be commenced in conjunction with thrombectomy. These results will serve as the basis for powering a phase III study to assess the efficacy of TH in conjunction with reperfusion therapy compared to reperfusion therapy alone. Conclusion There is limited evidence demonstrating the clinical benefit or impact of neuroprotection in conjunction with endovascular reperfusion therapy for acute ischemic stroke. Combining intravascular therapeutic hypothermia with endovascular reperfusion therapy may provide an opportunity to enhance clinical outcomes in patients with large vessel occlusion. Disclosures R. Gupta: 1; C; Stryker Neurovascular PI ASSIST Registry, Zoll PI RECCLAIM II (No compensation), Cerenovous Steering Committee MEMBRANE study, Medtronic Steering Committee ELEVATE Study, Penumbra CEC MIND Trial, Vesalio PI CLEAR Study, Rapid Medical PI Tiger Study. S. Zaidi: None. M. Jumaa: None. N. Badjatia: None. A. Yoo: 1; C; Medtronic, Cerenovous, Penumbra, Stryker, Genentech. 2; C; Cerenovous, Genentech. 6; C; Insera Therapeutics.

Biomarkers of Technical Success After Embolectomy for Acute Stroke

Abstract: Purpose of the Review Stent retrievers and large-bore aspiration catheters have doubled substantial reperfusion rates compared to first-generation devices. This has been accompanied by a 3-fold reduction in procedural time to revascularization. To measure future thrombectomy improvements, new benchmarks for technical efficacy are needed. This review summarizes the recent literature concerning biomarkers of procedural success and harm and highlights future directions. Recent Findings Expanded Treatment in Cerebral Ischemia (eTICI), which incorporates scores for greater levels of reperfusion, improves outcome prediction. Core laboratory–adjudicated studies show that outcomes following eTICI 2c (90%–99% reperfusion) are superior to eTICI 2b50 and nearly equivalent to eTICI 3. Moreover, eTICI 2c improves scale reliability. Studies also confirm the importance of rapid revascularization, whether measured as first pass effect or procedural duration under 30 minutes. Distal embolization is a complication that impedes the extent and speed of revascularization, but few studies have reported its per-pass occurrence. Distal embolization and emboli to new territory should be measured after each thrombectomy maneuver. Collaterals have been shown to be an important modifier of thrombectomy benefit. A drawback of the currently accepted collateral grading scale is that it does not discriminate among the broad spectrum of partial collateralization. Important questions that require investigation include reasons for failed revascularization, the utility of a global Treatment in Cerebral Ischemia scale, and the optimal grading system for vertebrobasilar occlusions. Summary Emerging data support a lead technical efficacy endpoint that combines the extent and speed of reperfusion. Efforts are needed to better characterize angiographic measures of treatment harm and of collateralization.

Embotrap Extraction & Clot Evaluation & Lesion Evaluation for NeuroThrombectomy (EXCELLENT) Registry design and methods.

Abstract: Background Relationships between occlusive clot histopathology, baseline characteristics, imaging findings, revascularization rates, and clinical outcomes of stroke patients with large vessel occlusion (LVO) are not well understood. This study will assess the real-world experience on the efficacy and safety of using the EmboTrap device as the first approach in LVO patients and explore the associations between clot histological characteristics, imaging and clinical findings, revascularization rates, and clinical outcomes. Methods Prospective, global, multicenter, single-arm, imaging core laboratory, and clot analysis central laboratory observational registry. Adult patients (>18 years) with LVO, treated with EmboTrap as the first attempted device, will be eligible for study participation. Results Up to 1000 subjects at 50 international sites may be enrolled. Occlusive clots will be collected from at least 500 subjects. Independent central and imaging core laboratories will perform clot analysis and image adjudication. Statistical analysis will assess the association between imaging and clinical findings, clot characteristics, subject comorbidities, revascularization, and clinical outcomes. Study endpoints are functional independence (modified Rankin Scale score ≤2 at 90 days), expanded Thrombolysis In Cerebral Infarction (eTICI) score ≥2b50 rate, first-pass effect, number of passes, embolization into new territory, symptomatic intracranial hemorrhage, and 90-day mortality. Conclusions The EXCELLENT registry will provide reproducible effectiveness and safety data of EmboTrap for its use for mechanical thrombectomy. Additionally, the study will characterize the blood clots retrieved during mechanical thrombectomy with respect to their composition and histopathological analysis and potential correlations with clinical and imaging findings. Trial registration number NCT03685578.

Serial ASPECTS in the DAWN Trial: Infarct Evolution and Clinical Impact.

Abstract: Background and purpose The impact of baseline ischemia on Alberta Stroke Program Early CT Score (ASPECTS) and evolution over 24 hours may be distinct in late thrombectomy. We analyzed predictors of serial ASPECTS and clinical outcomes in the DAWN trial (Diffusion-Weighted Imaging or CTP Assessment With Clinical Mismatch in the Triage of Wake-Up and Late Presenting Strokes Undergoing Neurointervention With Trevo). Methods The DAWN Imaging Core Laboratory independently scored ASPECTS at baseline and 24 hours. Descriptive statistics characterized ASPECTS on computed tomography/magnetic resonance imaging at baseline and 24 hours, delineating ASPECTS change over 24 hours. Results 206 subjects (mean age 70.0±13.7 years; 54.9% (n=113) female; baseline National Institutes of Health Stroke Scale median (interquartile range) 17 (13, 21) were included. Baseline ASPECTS was median (interquartile range) 8.0 (7-8), with 92/205 (44.9%) between 0 and 7 and 113/205 (55.1%) 8 and 10. 24-hour ASPECTS was median 6.0 (4-8), with ASPECTS change or infarct evolution having median -1, ranging from -8 to +2. Multivariable logistic regression showed older age (odds ratio [OR] for 10-year interval, 1.26 [95% CI, 1.02-1.55], P=0.030) and dyslipidemia (OR, 1.84 [95% CI, 1.06-3.19], P=0.031) were independently associated with higher baseline ASPECTS. Higher 24-hour ASPECTS was predicted by endovascular treatment (OR, 2.76 [95% CI, 1.58-4.81], P=0.0004), baseline glucose Conclusions DAWN subjects enrolled with small infarct cores had a broad range of baseline ASPECTS. Twenty-four-hour ASPECTS, strikingly influenced by endovascular therapy, predicted good clinical outcomes. REGISTRATION: https://www.clinicaltrials.gov; Unique identifier: NCT02142283.

EP45* Beyond proximal large vessel occlusions: outcome of mechanical thrombectomy in distal vessel occlusions in the EXCELLENT registry – Interim analysis

Abstract: OO Zaidat, RG Nogueira, AH Siddiqui, AJ Yoo, RA Hanel, W Hacke, T Jovin, J Fiehler, SF De Meyer, DS Liebeskind, D Haussen, V Inoa, W Humphries, KB Woodward, PM Jabbour, O Francois, EI Levy, H Bozorgchami, J Cohen, S Boor, SR Dashti, MA Taqi, RF Budzik, CM Schirmer, MS Hussain, L Estrade, RA De Leacy, AS Puri, R Chitale, C Brekenfeld, T Andersson. Neuroscience Department, Mercy St Vincent Medical Center, Toledo, OH; Department of Neurosurgery, Emory University School of Medicine, Atlanta, GA; Department of Neurosurgery, SUNY Buffalo, Buffalo, NY; Neurointervention, Texas Stroke Institute, Plano, TX; Department of Neurosurgery, Baptist Stroke and Cerebrovascular Center, Jacksonville, FL, USA; Department of Neurology, University of Heidelberg, Heidelberg, Germany; Department of Neurology, University of Pittsburgh Medical Center, Pittsburgh, PA; Department of Neurosurgery, University Medical Center Hamburg, Hamburg, GA, USA; Laboratory for Thrombosis Research, KU Leuven Campus Kulak Kortrijk, Kortrijk, Belgium; Department of Neurology, University of California Los Angeles, Los Angeles, CA; Marcus Stroke and Neuroscience Center, Grady Memorial Hospital, Atlanta, GA; Semmes-Murphey Neurologic and Spine Clinic, Department of Neurosurgery, University of Tennessee Health Science Center, Memphis, TN; Division of Neurosurgery, Department of Surgery, University of Missouri-Columbia Medical School, Columbia, MO; Department of Radiology, Fort Sanders Regional Medical Center, Knoxville, TN; Department of Neurological Surgery, Thomas Jefferson University Hospital, Philadelphia, PA, USA; Department of Medical Imaging, AZ Groeninge, Kortrijk, Belgium; Department of Neurosurgery, University at Buffalo, State University of New York, Buffalo, NY; Department of Neurology, Oregon Health and Sciences, Portland, OR, USA; Neurosurgery Department,, Hadassah University Medical Center, Jerusalem, Israel; Institute of Neuroradiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany; Department of Neurological Surgery Norton Neuroscience Institute, Norton Healthcare, Louisville, KY; Department of Neurology and Neurosurgery, Los Robles Hospital and Medical Center, Thousand Oaks, CA; Department of Radiology, Riverside Methodist Hospital, Columbus, OH; Department of Neurosurgery, Geisinger, Danville, PA; Cerebrovascular Center, Department of Neurology, Neurological Institute, Cleveland Clinic, Cleveland, OH, USA; Department of Interventional Neuroradiology, Centre Hospitalier Universitaire de Lille, Lille, France; Department of Neurosurgery, Icahn School of Medicine at Mount Sinai, New York, NY; Department of Radiology, University of Massachusetts, Worcester, MA; Department of Neurosurgery, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Neuroradiology, University Medical Center Hamburg, Hamburg, Germany; Department of Neuroradiology, Karolinska University Hospital and Clinical Neuroscience Karolinska Institute, Stockholm, Sweden; Medical Imaging, AZ Groeninge,, Kortrijk, Belgium

Effect of Hispanic Status in Mechanical Thrombectomy Outcomes After Ischemic Stroke: Insights From STAR.

Abstract: Background and Purpose: Epidemiological studies have shown racial and ethnic minorities to have higher stroke risk and worse outcomes than non-Hispanic Whites. In this cohort study, we analyzed the...