Endovascular Treatment for Acute Ischemic Stroke With or Without General Anesthesia: A Matched Comparison

BACKGROUND

Endovascular treatment in large artery occlusion stroke reduces disability. However, the impact of anesthesia type on clinical outcomes remains uncertain.

METHODS

We compared consecutive patients in the Swiss Stroke Registry with anterior circulation stroke receiving endovascular treatment with or without general anesthesia (GA). The primary outcome was disability on the modified Rankin Scale after 3 months, analyzed with ordered logistic regression. Secondary outcomes included dependency or death (modified Rankin Scale score ≥3), National Institutes of Health Stroke Scale after 24 hours, symptomatic intracranial hemorrhage with ≥4 points worsening on National Institutes of Health Stroke Scale within 7 days, and mortality. Coarsened exact matching and propensity score matching were performed to adjust for indication bias.

RESULTS

One thousand two hundred eighty-four patients (GA: n=851, non-GA: n=433) from 8 Stroke Centers were included. Patients treated with GA had higher modified Rankin Scale scores after 3 months than patients treated without GA, in the unmatched (odds ratio [OR], 1.75 [1.42-2.16]; P<0.001), the coarsened exact matching (n=332-524, using multiple imputations of missing values; OR, 1.60 [1.08-2.36]; P=0.020), and the propensity score matching analysis (n=568; OR, 1.61 [1.20-2.15]; P=0.001). In the coarsened exact matching analysis, there were no significant differences in National Institutes of Health Stroke Scale after 1 day (estimated coefficient 2.61 [0.59-4.64]), symptomatic intracranial hemorrhage (OR, 1.06 [0.30-3.75]), dependency or death (OR, 1.42 [0.91-2.23]), or mortality (OR, 1.65 [0.94-2.89]). In the propensity score matching analysis, National Institutes of Health Stroke Scale after 24 hours (estimated coefficient, 3.40 [1.76-5.04]), dependency or death (OR, 1.49 [1.07-2.07]), and mortality (OR, 1.65 [1.11-2.45]) were higher in the GA group, whereas symptomatic intracranial hemorrhage did not differ significantly (OR, 1.77 [0.73-4.29]).

CONCLUSIONS

This large study showed worse functional outcome after endovascular treatment of anterior circulation stroke with GA than without GA in a real-world setting. This finding appears to be independent of known differences in patient characteristics between groups.

Direct Oral Anticoagulants Versus Warfarin in the Treatment of Cerebral Venous Thrombosis (ACTION-CVT): A Multicenter International Study

BACKGROUND

A small randomized controlled trial suggested that dabigatran may be as effective as warfarin in the treatment of cerebral venous thrombosis (CVT). We aimed to compare direct oral anticoagulants (DOACs) to warfarin in a real-world CVT cohort.

METHODS

This multicenter international retrospective study (United States, Europe, New Zealand) included consecutive patients with CVT treated with oral anticoagulation from January 2015 to December 2020. We abstracted demographics and CVT risk factors, hypercoagulable labs, baseline imaging data, and clinical and radiological outcomes from medical records. We used adjusted inverse probability of treatment weighted Cox-regression models to compare recurrent cerebral or systemic venous thrombosis, death, and major hemorrhage in patients treated with warfarin versus DOACs. We performed adjusted inverse probability of treatment weighted logistic regression to compare recanalization rates on follow-up imaging across the 2 treatments groups.

RESULTS

Among 1025 CVT patients across 27 centers, 845 patients met our inclusion criteria. Mean age was 44.8 years, 64.7% were women; 33.0% received DOAC only, 51.8% received warfarin only, and 15.1% received both treatments at different times. During a median follow-up of 345 (interquartile range, 140-720) days, there were 5.68 recurrent venous thrombosis, 3.77 major hemorrhages, and 1.84 deaths per 100 patient-years. Among 525 patients who met recanalization analysis inclusion criteria, 36.6% had complete, 48.2% had partial, and 15.2% had no recanalization. When compared with warfarin, DOAC treatment was associated with similar risk of recurrent venous thrombosis (aHR, 0.94 [95% CI, 0.51-1.73]; P=0.84), death (aHR, 0.78 [95% CI, 0.22-2.76]; P=0.70), and rate of partial/complete recanalization (aOR, 0.92 [95% CI, 0.48-1.73]; P=0.79), but a lower risk of major hemorrhage (aHR, 0.35 [95% CI, 0.15-0.82]; P=0.02).

CONCLUSIONS

In patients with CVT, treatment with DOACs was associated with similar clinical and radiographic outcomes and favorable safety profile when compared with warfarin treatment. Our findings need confirmation by large prospective or randomized studies.

Abstract TP161: Embolization Of Intracranial Aneurysms Using WAVE Extra Soft Coils, A Part Of The Penumbra SMART COIL System: An Interim Analysis Of The SURF Study

Introduction: Initial clinical evidence has shown that coiling with the SMART COIL System (Penumbra, Inc.) is a safe and durable treatment option for intracranial aneurysms. The SURF study is a post-market, prospective, multicenter, single-arm, observational study to assess the utility of the WAVE Extra Soft Coil (WAVE) as fill and finishing coil to support adequate occlusion of intracranial aneurysms.

Methods: Enrollment began November 5, 2019; this analysis includes data as of July 20, 2021. Patients undergoing embolization of intracranial aneurysms with WAVE as the final finishing coil and Penumbra SMART COIL System accounting for at least 75% of the total number of coils implanted were enrolled consecutively at 34 centers globally. Post-procedure Raymond Roy Occlusion Classification (RROC) was assessed by a core lab. The estimated enrollment will be 800 patients.

Results: This analysis includes 346 patients, mean age 60.1 (SD 13.03), 73.1% female. Of the target aneurysms, 39.8% (135/339) were ruptured, and 80.5% (269/334) were saccular, and 11.5% (39/338) were previously treated. Post-procedure, 89.2% (206/231, 95% CI 85.2%, 93.2%) of aneurysms were RROC I or II. Device-related SAEs occurred in 1.5% (5/346, 95% CI 0.2%, 2.7%) of patients up to 7 days or discharge. The rate of major ipsilateral stroke was 0.6% (2/346), and the intra-procedural rupture rate was 0.6% (2/346).

Conclusions: We report interim outcomes from the SURF study. This post-market registry evaluates the safety and performance of the Penumbra SMART COIL System, including WAVE as fill and finishing coil, in the treatment of intracranial aneurysms.

Abstract 128: Evaluation Of Flat Panel Detector Whole Brain Perfusion Imaging In Acute Stroke Patients: Comparison With Computer Tomography Perfusion Imaging

Introduction: In acute ischemic stroke, perfusion imaging facilitates detection of the occluded vessels, influences decision-making regarding therapy options, and is recommended especially in delayed time windows. In contrast to conventional CT perfusion (CTP), flat panel detector CT perfusion (FD-CTP) can be acquired directly in the angio suite. To evaluate FD-CTP imaging, we assessed clinically important qualitative and quantitative perfusion parameters in correlation to prior acquired conventional CTP using the new RAPID for Angio software.

Methods: We included patients with ICA-, M1, or M2-occlusions from 6 centers. All patients underwent mechanical thrombectomy (MT) with pre-interventional conventional CTP and FD-CTP imaging. Quantitative performance was determined by comparing volumes of infarct core, penumbral tissue, and mismatch volume. Eligibility for MT according to the perfusion imaging criteria of DEFUSE 3 was determined for each case for conventional CTP and FD-CTP imaging. A blinded reader identified the occlusion site based on visual inspection of the FD-CTP maps.

Results: We included 77 patients and FD-CTP was technical adequate in 49 patients (63.6%). The final analysis included 20 patients (further reasons for exclusion were n=20 technical inadequate conventional CTP, n=2 reperfusion between scans, n=2 exceeding the time limit between scans, n=2 posterior occlusion and n=3 MRI-perfusion). Conventional rCBF <30% and FD-CTP rCBF <45% showed good correlation (R 2 = 0.84). Conventional CTP Tmax >6s/FD-CTP Tmax >6s and CTP Mismatch/FD-CTP Mismatch showed more variability (R 2 = 0.57, and R 2 = 0.33 respectively). Based on FD-CTP, 16/20 (80%) patients met the inclusion criteria for MT according to the DEFUSE 3 perfusion criteria in contrast to 18/20 (90%) patients based on conventional CTP. A blinded reader correctly determined the specific vessel occlusions in 34/38 cases (89.5%).

Conclusion: In our multicenter study, time-resolved whole-brain FD-CTP was technically feasible and qualitative and quantitative perfusion results correlated overall well with conventional CTP. This potentially enables a direct to the angio approach to be established and may increase the chances of good clinical outcome.

Cerebrovascular Collateral Integrity in Pediatric Large Vessel Occlusion: Analysis of the Save ChildS Study

BACKGROUND AND OBJECTIVES

Robust cerebrovascular collaterals in adult patients with large vessel occlusion stroke have been associated with longer treatment windows, better recanalization rates, and improved outcomes, but the role of collaterals in pediatric stroke is not known. The primary aim was to determine whether favorable collaterals correlated with better radiographic and clinical outcomes in children with ischemic stroke who underwent thrombectomy.

METHODS

This study analyzed a subset of children enrolled in SaveChildS, a retrospective, multicenter, observational cohort study of 73 pediatric patients with stroke who underwent thrombectomy between 2000 and 2018 at 27 US and European centers. Included patients had baseline angiographic imaging and follow-up modified Rankin Scale scores available for review. Posterior circulation occlusions were excluded. Cerebrovascular collaterals were graded on acute neuroimaging by 2 blinded neuroradiologists according to the Tan collateral score, in which favorable collaterals are defined as >50% filling and unfavorable collaterals as <50% filling distal to the occluded vessel. Collateral status was correlated with clinical and neuroimaging characteristics and outcomes. Between-group comparisons were performed with the Wilcoxon rank-sum test for continuous variables or Fisher exact test for binary variables.

RESULTS

Thirty-three children (mean age 10.9 [SD ±4.9]) years were included; 14 (42.4%) had favorable collaterals. Median final stroke volume as a percent of total brain volume (TBV) was significantly lower in patients with favorable collaterals (1.35% [interquartile range (IQR) 1.14%-3.76%] vs 7.86% [IQR 1.54%-11.07%], p = 0.049). Collateral status did not correlate with clinical outcome, infarct growth, or final Alberta Stroke Program Early CT Score (ASPECTS) in our cohort. Patients with favorable collaterals had higher baseline ASPECTS (7 [IQR 6-8] vs 5.5 [4-6], p = 0.006), smaller baseline ischemic volume (1.57% TBV [IQR 1.09%-2.29%] vs 3.42% TBV [IQR 1.26%-5.33%], p = 0.035), and slower early infarct growth rate (2.4 mL/h [IQR 1.5-5.1 mL/h] vs 10.4 mL/h [IQR 3.0-30.7 mL/h], p = 0.028).

DISCUSSION

Favorable collaterals were associated with smaller final stroke burden and slower early infarct growth rate but not with better clinical outcome in our study. Prospective studies are needed to determine the impact of collaterals in childhood stroke.

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that in children with ischemic stroke undergoing thrombectomy, favorable collaterals were associated with improved radiographic outcomes but not with better clinical outcomes.

Outcomes after reperfusion therapies in patients with ACA stroke: A multicenter cohort study from the EVATRISP collaboration

BACKGROUND

Patients with stroke secondary to occlusions of the anterior cerebral artery (ACA) often have poor outcomes. The optimal acute therapeutic intervention for these patients remains unknown.

METHODS

Patients with isolated ACA-stroke were identified from 10 centers participating in the EndoVascular treatment And ThRombolysis in Ischemic Stroke Patients (EVATRISP) prospective registry. Patients treated with endovascular thrombectomy (EVT) were compared to those treated with intravenous thrombolysis (IVT). Odds ratios with 95% confidence intervals (OR; 95%CI) were calculated using multivariate regression analysis.

RESULTS

Included were 92 patients with ACA-stroke. Of the 92 ACA patients, 55 (60%) were treated with IVT only and 37 (40%) with EVT (±bridging IVT). ACA patients treated with EVT had more often wake-up stroke (24% vs. 6%, p = 0.044) and proximal ACA occlusions (43% vs. 24%, p = 0.047) and tended to have higher stroke severity on admission [NIHSS: 10.0 vs 7.0, p = 0.054). However, odds for favorable outcome, mortality or symptomatic intracranial hemorrhage did not differ significantly between both groups. Exploration of the effect of clot location inside the ACA showed that in patients with A1 or A2/A3 ACA occlusions the chances of favorable outcome were not influenced by treatment allocation to IVT or EVT.

DISCUSSION

Treatment with either IVT or EVT could be safe with similar effect in patients with ACA-strokes and these effects may be independent of clot location within the occluded ACA.

Outcomes of Mechanical Thrombectomy for Patients With Stroke Presenting With Low Alberta Stroke Program Early Computed Tomography Score in the Early and Extended Window

IMPORTANCE

Limited data are available about the outcomes of mechanical thrombectomy (MT) for real-world patients with stroke presenting with a large core infarct.

OBJECTIVE

To investigate the safety and effectiveness of MT for patients with large vessel occlusion and an Alberta Stroke Program Early Computed Tomography Score (ASPECTS) of 2 to 5.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study used data from the Stroke Thrombectomy and Aneurysm Registry (STAR), which combines the prospectively maintained databases of 28 thrombectomy-capable stroke centers in the US, Europe, and Asia. The study included 2345 patients presenting with an occlusion in the internal carotid artery or M1 segment of the middle cerebral artery from January 1, 2016, to December 31, 2020. Patients were followed up for 90 days after intervention. The ASPECTS is a 10-point scoring system based on the extent of early ischemic changes on the baseline noncontrasted computed tomography scan, with a score of 10 indicating normal and a score of 0 indicating ischemic changes in all of the regions included in the score.

EXPOSURE

All patients underwent MT in one of the included centers.

MAIN OUTCOMES AND MEASURES

A multivariable regression model was used to assess factors associated with a favorable 90-day outcome (modified Rankin Scale score of 0-2), including interaction terms between an ASPECTS of 2 to 5 and receiving MT in the extended window (6-24 hours from symptom onset).

RESULTS

A total of 2345 patients who underwent MT were included (1175 women [50.1%]; median age, 72 years [IQR, 60-80 years]; 2132 patients [90.9%] had an ASPECTS of ≥6, and 213 patients [9.1%] had an ASPECTS of 2-5). At 90 days, 47 of the 213 patients (22.1%) with an ASPECTS of 2 to 5 had a modified Rankin Scale score of 0 to 2 (25.6% [45 of 176] of patients who underwent successful recanalization [modified Thrombolysis in Cerebral Ischemia score ≥2B] vs 5.4% [2 of 37] of patients who underwent unsuccessful recanalization; P = .007). Having a low ASPECTS (odds ratio, 0.60; 95% CI, 0.38-0.85; P = .002) and presenting in the extended window (odds ratio, 0.69; 95% CI, 0.55-0.88; P = .001) were associated with worse 90-day outcome after controlling for potential confounders, without significant interaction between these 2 factors (P = .64).

CONCLUSIONS AND RELEVANCE

In this cohort study, more than 1 in 5 patients presenting with an ASPECTS of 2 to 5 achieved 90-day functional independence after MT. A favorable outcome was nearly 5 times more likely for patients with low ASPECTS who had successful recanalization. The association of a low ASPECTS with 90-day outcomes did not differ for patients presenting in the early vs extended MT window.

CT Hypoperfusion-Hypodensity Mismatch to Identify Patients With Acute Ischemic Stroke Within 4.5 Hours of Symptom Onset

BACKGROUND AND OBJECTIVES

To test the hypothesis that CT hypoperfusion-hypodensity mismatch identifies patients with ischemic stroke within 4.5 hours of symptom onset.

METHODS

We therefore performed the Retrospective Multicenter Hypoperfusion-Hypodensity Mismatch for The identification of Patients With Stroke Within 4.5 Hours study of patients with acute ischemic stroke and known time of symptom onset. The predictive values of hypoperfusion-hypodensity mismatch for the identification of patients with symptom onset within 4.5 hours were the main outcome measure.

RESULTS

Of 666 patients, 548 (82.3%) had multimodal CT within 4.5 hours and 118 (17.7%) beyond 4.5 hours. Hypoperfusion-hypodensity mismatch was visible in 516 (94.2%) patients with symptom onset within and in 30 (25.4%) patients beyond 4.5 hours. CT hypoperfusion-hypodensity mismatch identified patients within 4.5 hours of stroke onset with 94.2% (95% confidence interval [CI] 91.9%-95.8%) sensitivity, 74.6% (95% CI 66.0%-81.6%) specificity, 94.5% (95% CI 92.3%-96.1%) positive predictive value, and 73.3% (95% CI 64.8%-80.4%) negative predictive value. Interobserver agreement for hypoperfusion-hypodensity mismatch was substantial (κ = 0.61, 95% CI 0.53-0.69).

DISCUSSION

Patients with acute ischemic stroke with absence of a hypodensity on native CT (NCCT) within the hypoperfused core lesion on perfusion CT (hypoperfusion-hypodensity mismatch) are likely to be within the time window of thrombolysis. Applying this method may guide the decision to use thrombolysis in patients with unknown time of stroke onset.

TRIAL REGISTRATION INFORMATION

ClinicalTrials.gov Identifier: NCT04277728.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that CT hypoperfusion-hypodensity mismatch identifies patients with stroke within 4.5 hours of onset.

Blood Pressure After Endovascular Thrombectomy and Outcomes in Patients With Acute Ischemic Stroke: An Individual Patient Data Meta-analysis

OBJECTIVE

To explore the association between blood pressure (BP) levels after endovascular thrombectomy (EVT) and the clinical outcomes of acute ischemic stroke (AIS) patients with large vessel occlusion (LVO).

METHODS

A study was eligible if it enrolled AIS patients older than 18 years, with an LVO treated with either successful or unsuccessful EVT, and provided either individual or mean 24-hour systolic BP values after the end of the EVT procedure. Individual patient data from all studies were analyzed using a generalized linear mixed-effects model.

RESULTS

A total of 5874 patients (mean age: 69±14 years, 50% women, median NIHSS on admission: 16) from 7 published studies were included. Increasing mean systolic BP levels per 10 mm Hg during the first 24 hours after the end of the EVT were associated with a lower odds of functional improvement (unadjusted common OR=0.82, 95%CI:0.80-0.85; adjusted common OR=0.88, 95%CI:0.84-0.93) and modified Ranking Scale score≤2 (unadjusted OR=0.82, 95%CI:0.79-0.85; adjusted OR=0.87, 95%CI:0.82-0.93), and a higher odds of all-cause mortality (unadjusted OR=1.18, 95%CI:1.13-1.24; adjusted OR=1.15, 95%CI:1.06-1.23) at 3 months. Higher 24-hour mean systolic BP levels were also associated with an increased likelihood of early neurological deterioration (unadjusted OR=1.14, 95%CI:1.07-1.21; adjusted OR=1.14, 95%CI:1.03-1.24) and a higher odds of symptomatic intracranial hemorrhage (unadjusted OR=1.20, 95%CI:1.09-1.29; adjusted OR=1.20, 95%CI:1.03-1.38) after EVT.

CONCLUSION

Increased mean systolic BP levels in the first 24 hours after EVT are independently associated with a higher odds of symptomatic intracranial hemorrhage, early neurological deterioration, three-month mortality, and worse three-month functional outcomes.

Distribution of Diagnoses and Clinical and Imaging Characteristics in 1,322 Consecutive Suspected Stroke Patients

Background: Endovascular thrombectomy (EVT) has become the standard of care for large-vessel occlusion strokes, but several barriers for implementing an optimal organization of stroke management remain. Major issues include the lack of reliable data on the percentage of stroke patients potentially eligible for EVT especially in times of expanding indications for EVT. Our aim was therefore to study the frequencies of possible EVT-eligible patients such as patients with medium-vessel occlusions, patients with low Alberta Stroke Program Early Computed Tomography Scores (ASPECTS), patients presenting in an extended time window after onset of symptoms, and patients with mild symptoms at presentation (National Institutes of Health Stroke Scale, NIHSS ≤ 5). We also give detailed imaging and clinical information about the patients presenting with intracranial hemorrhage and other ischemic stroke mimics stratified by symptoms at presentation.

Methods: Cohort study of all consecutive patients with suspected acute stroke presenting to a tertiary care center in Germany between September 1, 2016, and August 31, 2017. Baseline and follow-up clinical and imaging characteristics were collected from patients' medical charts.

Results: Of 1,322 patients with a suspected acute stroke, 592 (44.8%) had ischemic strokes, 221 (16.7%) had hemorrhagic strokes, 190 (10.9%) had transient ischemic attacks (TIAs), and 319 (24.1%) were classified as stroke mimics. Stroke severity was mild (NIHSS ≤ 5) in 866 (65.5%) patients; 15.7% of the patients with an occlusion of the anterior circulation had an ASPECTS ≤ 5, 17.4% of the patients with an ischemic stroke had distal vessel occlusions, and 49% of the patients presented later than 6 h after onset of symptoms.

Conclusion: Our results help to plan resources in thrombectomy-capable centers in times of expanding indications for EVT where resources will have to be adjusted to patients with low-NIHSS, low-ASPECTS, and distal occlusions, and patients presenting in the extended time window, which may altogether account for an additional 20% of all ischemic stroke patients.

A Prospective Multicenter Registry on Feasibility, Safety, and Outcome of Endovascular Recanalization in Childhood Stroke (Save ChildS Pro)

Rationale: Early evidence for the benefit of mechanical thrombectomy (MT) in pediatric patients with intracranial large vessel occlusion has been shown in previous retrospective cohorts. Higher-level evidence is needed to overcome the limitations of these studies such as the lack of a control group and the retrospective design. Randomized trials will very likely not be feasible, and several open questions remain, for example, the impact of arteriopathic etiologies or a possible lower age limit for MT. Save ChildS Pro therefore aims to demonstrate the safety and effectiveness of MT in pediatric patients compared to the best medical management and intravenous thrombolysis.

Design: Save ChildS Pro is designed as a worldwide multicenter prospective registry comparing the safety and effectiveness of MT to the best medical care alone in the treatment of pediatric arterial ischemic stroke (AIS). It will include pediatric patients (<18 years) with symptomatic acute intracranial arterial occlusion who underwent either MT or best medical treatment including intravenous thrombolysis.

Outcomes: The primary endpoint of Save ChildS Pro is the modified Rankin Scale score at 90 days post-stroke. Secondary endpoints will comprise the decrease of the Pediatric National Institutes of Health Stroke Scale score from admission to discharge and rate of complications.

Discussion: Save ChildS Pro aims to provide high-level evidence for MT for pediatric patients with AIS, thereby improving functional outcome and quality of life and reducing the individual, societal, and economic burden of death and disability resulting from pediatric stroke.

Clinical Trial Registration: Save ChildS Pro is registered at the German Clinical Trials Registry (DRKS; identifier: DRKS00018960).

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

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 STAR (Stroke Thrombectomy and Aneurysm Registry) database, a multi-institutional database of patients who underwent mechanical thrombectomy for acute large vessel occlusion stroke to determine the relationship between mechanical thrombectomy outcomes and race.

Methods

Patients who underwent mechanical thrombectomy between January 2017 and May 2020 were analyzed. Data included baseline characteristics, vascular risk factors, complications, and long-term outcomes. Functional outcomes were assessed with respect to Hispanic status delineated as non-Hispanic White (NHW), non-Hispanic Black (NHB), or Hispanic patients. Multivariate analysis was performed to identify variables associated with unfavorable outcome or modified Rankin Scale ≥3 at 90 days.

Results

Records of 2115 patients from the registry were analyzed. Median age of Hispanic patients undergoing mechanical thrombectomy was 60 years (72–84), compared with 63 years (54–74) for NHB, and 71 years (60–80) for NHW patients (P<0.001). Hispanic patients had a higher incidence of diabetes (41%; P<0.001) and hypertension (82%; P<0.001) compared with NHW and NHB patients. Median procedure time was shorter in Hispanics (36 minutes) compared to NHB (39 minutes) and NHW (44 minutes) patients (P<0.001). In multivariate analysis, Hispanic patients were less likely to have favorable outcome (odds ratio, 0.502 [95% CI, 0.263–0.959]), controlling for other significant predictors (age, admission National Institutes Health Stroke Scale, onset to groin time, number of attempts, procedure time).

Conclusions

Hispanic patients are less likely to have favorable outcome at 90 days following mechanical thrombectomy compared to NHW or NHB patients. Further prospective studies are required to validate our findings.

EndoVAscular treatment and ThRombolysis for Ischemic Stroke Patients (EVA-TRISP) registry: basis and methodology of a pan-European prospective ischaemic stroke revascularisation treatment registry

PURPOSE

The Thrombolysis in Ischemic Stroke Patients (TRISP) collaboration was a concerted effort initiated in 2010 with the purpose to address relevant research questions about the effectiveness and safety of intravenous thrombolysis (IVT). The collaboration also aims to prospectively collect data on patients undergoing endovascular treatment (EVT) and hence the name of the collaboration was changed from TRISP to EVA-TRISP. The methodology of the former TRISP registry for patients treated with IVT has already been published. This paper focuses on describing the EVT part of the registry.

PARTICIPANTS

All centres committed to collecting predefined variables on consecutive patients prospectively. We aim for accuracy and completeness of the data and to adapt local databases to investigate novel research questions. Herein, we introduce the methodology of a recently constructed academic investigator-initiated open collaboration EVT registry built as an extension of an existing IVT registry in patients with acute ischaemic stroke (AIS).

FINDINGS TO DATE

Currently, the EVA-TRISP network includes 20 stroke centres with considerable expertise in EVT and maintenance of high-quality hospital-based registries. Following several successful randomised controlled trials (RCTs), many important clinical questions remain unanswered in the (EVT) field and some of them will unlikely be investigated in future RCTs. Prospective registries with high-quality data on EVT-treated patients may help answering some of these unanswered issues, especially on safety and efficacy of EVT in specific patient subgroups.

FUTURE PLANS

This collaborative effort aims at addressing clinically important questions on safety and efficacy of EVT in conditions not covered by RCTs. The TRISP registry generated substantial novel data supporting stroke physicians in their daily decision making considering IVT candidate patients. While providing observational data on EVT in daily clinical practice, our future findings may likewise be hypothesis generating for future research as well as for quality improvement (on EVT). The collaboration welcomes participation of further centres willing to fulfill the commitment and the outlined requirements.

[Stroke Unit- / Stroke Center Care]

Stroke Unit- / Stroke Center Care Abstract. About 16'000 people in Switzerland suffer from stroke, each year. In Switzerland, 23 Stroke units and Stroke centers are available to provide individual care for the vast majority of stroke patients. Comprehensive, interdisciplinary therapeutic strategies are standardized and include prevention and therapy of acute complications, expedited diagnostic workup, and early rehabilitation. Stroke units not only reduce mortality and permanent disability in stroke patients, but-alongside advanced recanalization therapies-represent the cornerstone of modern stroke care. The following article gives a detailed overview of core tasks and the current standards of treatment in stroke unit care.

Utility of Intravenous Alteplase Prior to Endovascular Stroke Treatment: A Systematic Review and Meta-analysis of RCTs

OBJECTIVE

To provide a critical appraisal on the evidence from randomized controlled clinical trials (RCTs) on the utility of direct endovascular treatment (dEVT) compared to the combination of endovascular treatment preceded by IV thrombolysis (bridging therapy [BT]) for patients with acute large vessel occlusion (LVO).

METHODS

Eligible RCTs were identified by searching Medline and Scopus. We calculated the corresponding odds ratios (ORs) and 95% confidence intervals (CIs) and pooled estimates using random-effects models. The primary outcome was the probability of modified Rankin scale (mRS) score of 0 to 2 at 3 months.

RESULTS

We included 3 studies comprising 1,092 patients. No difference between the dEVT and BT groups was detected for the outcomes of mRS score of 0 to 2 (OR 1.08, 95% CI 0.85-1.38; adjusted OR 1.11, 95% CI 0.76-1.63), mRS score of 0 to 1 (OR 1.10, 95% CI 0.84-1.43; adjusted OR 1.16, 95% CI 0.84-1.61), and functional improvement at 3 months (common OR 1.08, 95% CI 0.88-1.34; adjusted common OR 1.09, 95% CI 0.86-1.37). Patients receiving dEVT had significantly lower likelihood of successful recanalization before the endovascular procedure compared to those receiving BT (OR 0.37, 95% CI 0.18-0.77). Patients receiving dEVT had lower intracranial bleeding rates compared to those receiving BT (OR 0.67, 95% CI 0.49-0.92) but without a significant difference in the probability of symptomatic intracranial hemorrhage. No differences in all-cause mortality, serious adverse events, or procedural complications between the 2 groups were uncovered.

CONCLUSIONS

We detected no differences in functional outcomes of IV thrombolysis-eligible patients with an acute LVO receiving dEVT compared to BT. Because uncertainty for most endpoints remains large and the available data are not able to exclude the possibility of overall benefit or harm, further RCTs are needed.

Decline in subarachnoid haemorrhage volumes associated with the first wave of the COVID-19 pandemic

Background

During the COVID-19 pandemic, decreased volumes of stroke admissions and mechanical thrombectomy were reported. The study’s objective was to examine whether subarachnoid haemorrhage (SAH) hospitalisations and ruptured aneurysm coiling interventions demonstrated similar declines.

Methods

We conducted a cross-sectional, retrospective, observational study across 6 continents, 37 countries and 140 comprehensive stroke centres. Patients with the diagnosis of SAH, aneurysmal SAH, ruptured aneurysm coiling interventions and COVID-19 were identified by prospective aneurysm databases or by International Classification of Diseases, 10th Revision, codes. The 3-month cumulative volume, monthly volumes for SAH hospitalisations and ruptured aneurysm coiling procedures were compared for the period before (1 year and immediately before) and during the pandemic, defined as 1 March–31 May 2020. The prior 1-year control period (1 March–31 May 2019) was obtained to account for seasonal variation.

Findings

There was a significant decline in SAH hospitalisations, with 2044 admissions in the 3 months immediately before and 1585 admissions during the pandemic, representing a relative decline of 22.5% (95% CI −24.3% to −20.7%, p<0.0001). Embolisation of ruptured aneurysms declined with 1170–1035 procedures, respectively, representing an 11.5% (95%CI −13.5% to −9.8%, p=0.002) relative drop. Subgroup analysis was noted for aneurysmal SAH hospitalisation decline from 834 to 626 hospitalisations, a 24.9% relative decline (95% CI −28.0% to −22.1%, p<0.0001). A relative increase in ruptured aneurysm coiling was noted in low coiling volume hospitals of 41.1% (95% CI 32.3% to 50.6%, p=0.008) despite a decrease in SAH admissions in this tertile.

Interpretation

There was a relative decrease in the volume of SAH hospitalisations, aneurysmal SAH hospitalisations and ruptured aneurysm embolisations during the COVID-19 pandemic. These findings in SAH are consistent with a decrease in other emergencies, such as stroke and myocardial infarction.

Expanding indications for endovascular thrombectomy-how to leave no patient behind

Endovascular thrombectomy (EVT) has become standard of care for large vessel occlusion strokes but current guidelines exclude a large proportion of patients from this highly effective treatment. This review therefore focuses on expanding indications for EVT in several borderline indications such as patients in the extended time window, patients with extensive signs of infarction on admission imaging, elderly patients and patients with pre-existing deficits. It also discusses the current knowledge on intravenous thrombolysis as an adjunct to EVT and EVT as primary therapy for distal vessel occlusions, for tandem occlusions, for basilar artery occlusions and in pediatric patients. We provide clear recommendations based on current guidelines and further literature.

Correlation between different instrumentation variants and the degree of destabilization in treating cervical spondylotic spinal canal stenosis by unilateral hemilaminectomy with bilateral decompression: a biomechanical investigation

PURPOSE

Unilateral hemilaminectomy with bilateral decompression (BDZ) was proposed as an alternative decompressive procedure in cervical spondylotic myelopathy (CSM). Despite promising clinical results, the destabilizing effect is yet unknown. We therefore performed a biomechanical study to investigate whether lateral mass screw fixation should follow BDZ.

METHODS

Six human C2-C7 cervical specimens were tested under various conditions: native, unilateral hemilaminectomy with bilateral decompression without/with fixation (BDZ/BDF), unilateral hemilaminectomy with bilateral decompression and unilateral foraminotomy without/with fixation (UFZ/UFF), unilateral hemilaminectomy with bilateral decompression and bilateral foraminotomy without/with fixation (BFZ/BFF), and laminectomy without/with fixation (LAZ/LAF). Instrumention was applied from C3-C6. For each condition, the three-dimensional kinematics of the cervical specimen were measured in three main loading directions with an ultrasonic motion analysis system. ANOVA was used to determine differences between the specific segment conditions to assess the parameter's range of motion (ROM) and neutral zone (NZ).

RESULTS

For flexion-extension, lateral bending and axial rotation, ROM of BDZ, UFZ, BFZ and LAZ remained at the level of the native condition (p > 0.74), whereas fixation reduced ROM significantly (p < 0.01). Between BDF, UFF, BFF and LAF, no significant differences in reduction in ROM were seen (p > 0.49). Results for NZ were equivalent to ROM in flexion-extension and lateral bending. For axial rotation, NZ remained almost constant on the native level for all tested conditions.

CONCLUSION

Bilateral decompression via a hemilaminectomy, even if combined with foraminotomy, could be a less invasive treatment option for multilevel CSM in patients with lordotic cervical alignment and absence of segmental instability.

Abstract P504: Outcomes and Predictors of Successful First Pass in MCA Occlusions Using ADAPT Thrombectomy Technique - Insights From STAR

Introduction: Successful first pass (SFP) has been identified as a key benchmark of the success of mechanical thrombectomy (MT). However, studies that evaluate the predictors and outcomes of SFP using ADAPT (A Direct Aspiration first Pass Technique) are limied by the small number of patients or single center design.

Methods: We used data from the prospectively collected data from 28 stroke centers that are included in the Stroke Thrombectomy and Aneurysm Registry (STAR). Patients with middle cerebral artery (MCA) occlusions at the level of M1 or M2 segments were included. SFP was defined by achieving modified Thrombolysis in Cerebral Infarction (mTICI) score≥2b with a single aspiration attempt. A multivariable logistic regression analysis was used to assess the predictors of SFP and evaluate the relationship between SFP and favorable 90-day outcome (90-day modified Rankin scale ≤2).

Results: Out of 6123 patients included in STAR, 1002 (16.4%) underwent MT of M1 or M2 occlusion using ADAPT technique. SFP was achieved in 390 (38.9%) patients. SFP patients were older (72 vs. 69, P=0.007), had higher Alberta Stroke Program Early CT Score (ASPECTS) on presentation (9 vs. 8, P=0.018) (Table 1). On multivariable analysis, neither age (aOR 1.006, 95% CI 0.996-1.016, P=0.252) nor ASPECTS (aOR 1.055, 95% CI 0.976-1.141, P=0.179) were independent predictor of SFP. Importantly, SFP was independently associated with favorable 90-day outcome (aOR 2.769, 95% CI 1.988-3.858, P<0.001) after controlling for age, sex, ASPECTS, history of atrial fibrillation, NIHSS on presentation, onset to groin time and IV-tPA.

Conclusion: In this cohort of patients with M1 or M2 occlsuion undergoing MT using ADAPT technique, patients who had SFP were older and had better ASPECTS. However, both age and ASPECTS were not independently associated with SFP. Also, patients who had SFP were almost 3 times more likely to achieve favorable 90-day outcome.

Abstract P6: Impact of Ethnicity on the Outcomes of Mechanical Thrombectomy- Insights From Star

Introduction: Previous studies have reported that Hispanic stroke patients have limited access to mechanical thrombectomy (MT) compared to other ethnic groups. This has resulted in worse stroke outcomes in this group. However, limited data is available about the outcomes of MT in Hispanic patients.

Methods: We used data from the Stroke Thrombectomy and Aneurysm Registry (STAR) that combined the prospectively maintained databases of 28 thrombectomy-capable stroke centers in the US, Europe, and Asia. Consecutive patients who underwent MT were included in these analyses and patients were divided into 2 groups (Hispanics vs. non-Hispanics). Baseline features, time from symptom onset, thrombolysis receipt, final thrombolysis in cerebral infarction (TICI) score, symptomatic hemorrhage, and 90-day functional outcomes (measured by modified Rankin scale-mRS) were compared between Hispanic and non-Hispanics patients. A generalized linear model with logit link was used to assess the relationship between ethnicity and favorable outcomes at 90-day (mRS 0-2) controlling for confounders.

Results: We included 2015 patients in these analyses. Of those, 285 (14.1%) were Hispanic. As shown in table 1, Hispanic patients were older (72 vs. 70, p=0.007), more likely to have diabetes (41.1% vs. 26.5%, p<0.001), and more likely to have hypertension (81.8% vs. 73.7%, p=0.004). Importantly, Hispanics had a shorter procedure duration with a similar rate of successful recanalization (TICI≥2B). On multivariable analysis, Hispanic ethnicity was associated with a lower probability of favorable 90-day outcome (aOR 0.659, 95% CI 0.494-0.879, P=0.005) after controlling for age, stroke risk factors and location of occlusion.

Conclusion: Hispanic patients receiving MT have higher rate of stroke risk factors including diabetes and hypertension. Moreover, Hispanic ethnicity was independently associated with lower probability of favorable 90-day outcome.

Abstract P793: Extracellular Vesicles Enhance Blood-Brain Barrier Integrity by Nf-κB Dependent Regulation of Abcb1 in Stroke Mice

Extracellular vesicles (EVs) derived from neural progenitor cells (NPCs) enhance post-stroke neurological recovery, albeit the underlying mechanisms remain elusive. Since previous research described an enhanced post-stroke integrity of the blood-brain barrier (BBB) upon systemic transplantation of NPCs, we wondered if NPC-derived EVs affect BBB stability and which cellular mechanisms might be involved in the process. Using an in vitro co-culture model of brain endothelial cells (ECs) and astrocytes, cells were treated with EVs or PBS and exposed to oxygen-glucose-deprivation (OGD) injury. The readout parameters focused on the expression of ABCB1, an ATP-binding cassette (ABC) transporter expressed on ECs contributing to BBB integrity. Further in vitro analysis examined the pro-inflammatory NF-κB pathway, the permeability and the transcellular electrical resistance (TER) of cultured ECs. In vitro data was finally confirmed using a rodent stroke model. Cultured ECs displayed increased ABCB1 levels when exposed to OGD, which was reversed by treatment with EVs. The latter was due to an EV-induced inhibition of the NF-κB pathway. Using a BBB co-culture model of ECs and astrocytes exposed to OGD, EVs stabilized the BBB and ABCB1 levels without affecting TER. Likewise, EVs yielded reduced Evans blue extravasation, decreased ABCB1 expression as well as an inhibition of the NF-κB pathway and downstream matrix metalloprotease-9 activity in stroke mice. The EV-induced inhibition of the NF-κB pathway resulted in a post-stroke modulation of immune responses. Our findings suggest that EVs enhance post-stroke BBB integrity via ABCB1 and MMP-9 regulation, attenuating inflammatory cell recruitment by inhibition of the NF-κB pathway.

Abstract P20: Bridging Therapy Increases Hemorrhagic Complications Without Improving Functional Outcomes in Atrial Fibrillation Associated Stroke

* on behalf of the Stroke Thrombectomy and Aneurysm Registry (STAR) Collaborators

Introduction: Intravenous thrombolysis complications are enriched in AF associated stroke, as these patients have worse functional outcomes, less effective recanalization, and increased rates of hemorrhagic complications. These data suggest that AF patients may be at particularly high risk for complications of bridging therapy for large vessel occlusions treated with mechanical thrombectomy (MT). Here we determine whether clinical outcomes differ in AF associated stroke treated with MT and bridging therapy.

Methods: We performed a retrospective cohort study of the Stroke and Aneurysm Registry (STAR) from January 2015 to December 2018 and identified 4,169 patients who underwent MT for an anterior circulation stroke, 1,517 (36.4 %) of which had comorbid AF. Prospectively defined baseline characteristics and clinical outcomes were compared.

Results: Hemorrhagic complications after MT were similar in patients with or without AF. In patients without AF, bridging therapy improved 90-day outcomes (aOR 1.32, 1.02-1.74, p<0.05) without increasing hemorrhagic complications. In patients with AF, bridging therapy independently predicted hemorrhagic complications in AF patients (aOR 2.08, 1.06-4.06, p<0.033) without improving functional outcomes.

Conclusions: Bridging therapy in AF patients undergoing thrombectomy independently increased the odds of intracranial hemorrhage and did not improve functional outcomes. AF patients may represent a high-risk subgroup for thrombolytic complications. Randomized trials are warranted to determine whether patients with AF associated stroke may benefit by deferring bridging therapy at thrombectomy-capable centers.

Abstract MP33: Association Between Neurologic Outcomes and Temporal Profile of Systolic Blood Pressure Variability After Endovascular Thrombectomy

Introduction: Higher systolic blood pressure variability (BPV) after endovascular thrombectomy (EVT) has been associated with an increased risk of hemorrhagic transformation and worse functional outcomes. However, the time-varying behavior of BPV after EVT and its effects on functional outcome have not been well characterized.

Methods: We analyzed data from an international cohort of patients with acute large-vessel occlusion stroke who underwent EVT at 11 centers across North America, Europe, and Asia. Repeated time-stamped blood pressure data were recorded for the first 72 hours after thrombectomy. Parameters of BPV were calculated in 12-hour epochs using five established methodologies: standard deviation (SD), coefficient of variation (CV), average real variability (ARV), successive variation (SV), and residual SD (rSD). Patients’ overall mean BPV was then used to assign patients into tertiles for regression analysis: low BPV, intermediate BPV, and high BPV. Functional outcome was measured with the modified Rankin Scale (mRS) at 90 days.

Results: Of the 1,791 patients (age 69 ± 14, NIHSS 15 ± 6) included in our analysis, 1,085 (60.6%) had a poor 90-day outcome (mRS >3). Patients with poor outcome had significantly higher systolic BPV (p<0.05) measured as standard deviation (SBP SD) at each epoch (Figure 1B). Compared to patients with low BPV, those in the highest tertile group had significantly greater odds of a poor functional outcome after adjusting for age, sex, hypertension, NIHSS, ASPECT, tPA, time to reperfusion, and TICI score (OR 1.5; 95% CI 1.2-2; p=0.001). Patients in the highest tertile of BPV demonstrated time-dependent variability with the highest SBP SD during the first 24 hours after thrombectomy (Figure 1A).

Conclusions: Higher BPV measured by SBP SD appears to be associated with poor 90-day outcome in EVT-treated stroke patients. Early treatment strategies targeting early high BPV warrant further prospective investigation.

Abstract P479: A Tale of Two Clots: A Multicenter Study on Multiple Territory Thrombectomy

Introduction: The benefit of thrombectomy for large vessel occlusion (LVO) is well proven. There is minimal data on concurrent thrombectomy for multi-territory occlusions.

Methods: We reviewed the STAR registry from 2015-8 for patients treated with either right and left sided thrombectomy or anterior and posterior circulation thrombectomy at 15 comprehensive stroke centers.

Results: There were 4966 patients in the study period who had completed outcome data and LVO thrombectomy. 38 (0.8%) underwent endovascular thrombectomy for multi-territory occlusions. 26% had bilateral occlusions and 74% had anterior and posterior circulation occlusions. Among the 38, 50% were female, 49% were white, and 91% had a prestroke mRS<3. 95% had an ASPECT score of >6 and 55% received iv t-pa. 83% of patients had successful recanalization (TICI 2B/3) for both territories. The overall complication rate was 15%. 5% of patients had sICH or PH2. 26% of patients had a 90day mRS<2. When controlling for admission NIHSS, baseline mRS, age, comorbidities, and ASPECT in logistic regression analysis, multiple territory compared to single territory did not predict increased risk of sICH (p=0.73, 95%CI: 0.2-3.3), rate of TICI2B/3 (OR for TICI2B+: 0.93, p=0.88, CI: 0.38 - 2.3), or worse outcome (OR for good outcome: 0.6, p=.212, CI: 0.3-1.3). On linear regression analysis for attempts and procedure time, multiple territory thrombectomy required significantly higher number of attempts (Coefficient +1.8, p=0.001) without a significantly longer procedure time (Coefficient = +10, p=0.244).

Conclusion: With similar selection to single territory LVOs, good outcome can be achieved in multi-territory infarction with reasonable procedure time and no additional risk of hemorrhage or poor outcome.

Safety and Outcome of Carotid Dissection Stenting During the Treatment of Tandem Occlusions

Background and Purpose:

The efficacy of endovascular therapy in patients with acute ischemic stroke due to tandem occlusion is comparable to that for isolated intracranial occlusion in the anterior circulation. However, the optimal management of acute cervical internal carotid artery lesions is unknown, especially in the setting of carotid dissection, but emergency carotid artery stenting (CAS) is frequently considered. We investigated the safety and efficacy of emergency CAS for carotid dissection in patients with acute stroke with tandem occlusion in current clinical practice.

Methods:

We retrospectively analyzed a prospectively maintained database composed of 2 merged multicenter international observational real-world registries (Endovascular Treatment in Ischemic Stroke and Thrombectomy in Tandem Lesion). Data from endovascular therapy performed in the treatment of tandem occlusions related to acute cervical carotid dissection between January 2012 and January 2019 at 24 comprehensive stroke centers were analyzed.

Results:

The study assessed 136 patients with tandem occlusion due to dissection, including 65 (47.8%) treated with emergency CAS and 71 (52.2%) without. The overall rates of favorable outcome (90-day modified Rankin Scale score, 0–2) and successful reperfusion (modified Thrombolysis in Cerebral Infarction, 2b–3) were 58.0% (n=76 [95% CI, 49.6%–66.5%]) and 77.9% (n=106 [95% CI, 71.0%–85.0%]), respectively. In subgroup analyses, the rate of successful reperfusion (89.2% versus 67.6%; adjusted odds ratio, 2.24 [95% CI, 1.33–3.77]) was higher after CAS, whereas the 90-day favorable outcome (54.3% versus 61.4%; adjusted odds ratio, 0.84 [95% CI, 0.58–1.22]), symptomatic intracerebral hemorrhage (sICH; 10.8% versus 5.6%; adjusted odds ratio, 1.59 [95% CI, 0.79–3.17]), and 90-day mortality (8.0% versus 5.8%; adjusted odds ratio, 1.00 [95% CI, 0.48–2.09]) did not differ. In sensitivity analyses of patients with successful intracranial reperfusion, CAS was not associated with an improved clinical outcome.

Conclusions:

Emergency stenting of the dissected cervical carotid artery during endovascular therapy for tandem occlusions seems safe, whatever the quality of the intracranial reperfusion.