Reperfusion Grade Research Articles

Effects of reperfusion grade and reperfusion strategy on the clinical outcome: Insights from ESCAPE-NA1 trial.

We evaluated the association of reperfusion quality and different patterns of achieved reperfusion with clinical and radiological outcomes in the ESCAPE NA1 trial. Data are from the ESCAPE-NA1 trial. Good clinical outcome [90-day modified Rankin Scale (mRS) 0-2], excellent outcome (90-day mRS0-1), isolated subarachnoid hemorrhage, symptomatic hemorrhage (sICH) on follow-up imaging, and death were compared across different levels of reperfusion defined by expanded Treatment in Cerebral Infarction (eTICI) Scale. Comparisons were also made between patients with (a) first-pass eTICI 2c3 reperfusion vs multiple-pass eTICI 2c3; (b) final eTICI 2b reperfusion vs eTICI 2b converted-to-eTICI 2c3; (c) sudden reperfusion vs gradual reperfusion if >1 pass was required. Multivariable logistic regression was used to test associations of reperfusion grade and clinical outcomes. Of 1037 included patients, final eTICI 0-1 was achieved in 46 (4.4%), eTICI 2a in 76 (7.3%), eTICI 2b in 424 (40.9%), eTICI 2c in 284 (27.4%), and eTICI 3 in 207 (20%) patients. The odds for good and excellent clinical outcome gradually increased with improved reperfusion grades (adjOR ranging from 5.7-29.3 and 4.3-17.6) and decreased for sICH and death. No differences in outcomes between first-pass versus multiple-pass eTICI 2c3, eTICI 2b converted-to-eTICI 2c3 versus unchanged eTICI 2b and between sudden versus gradual eTICI 2c3 reperfusion were observed. Better reperfusion degrees significantly improved clinical outcomes and reduced mortality, independent of the number of passes and whether eTICI 2c3 was achieved suddenly or gradually.

Assessment of automated TICI scoring during endovascular treatment in patients with an ischemic stroke

BackgroundThe extended Thrombolysis in Cerebral Infarction (eTICI) score is used in digital subtraction angiography (DSA) to quantify reperfusion grade in patients with an ischemic stroke who undergo endovascular thrombectomy (EVT)....

After early mTICI 2b, stop or continue? Insights from the PERSIST Registry.

A higher reperfusion grade after endovascular thrombectomy (EVT) is associated with a good prognosis. However, the effect of the number of retrievals has not yet been investigated in vertebrobasilar occlusion (VBAO). Therefore, the aim of this study was to investigate whether to continue retrieval after early modified thrombolysis in cerebral infarction (mTICI) 2b to achieve a better reperfusion grade. We retrospectively analyzed the data of patients who underwent EVT caused by VBAO in a multicenter registry dataset. Patients who underwent successful reperfusion were included (mTICI 2b/3). Regression models were used to analyze the correlation of different reperfusion grades stratified by the number of retrieval attempts with clinical prognosis and hemorrhage transition. We included 432 patients: 34.5% (n = 149) had a final mTICI score of 2b and 65.5% (n = 283) had a final mTICI score of 3. Patients who obtained a mTICI of 3 after the first pass had significantly increased odds of having a good prognosis. As the number of passes increases, the chances of obtaining a good prognosis decreases. After three or more passes, the odds of achieving functional independence and favorable outcomes were comparable to those of the first mTICI 2b, regardless of the 90-day (OR 1.132 95% CI 0.367-3.487 p = 0.829; OR 1.070 95% CI 0.375-3.047 p = 0.900) or 1-year follow-up (OR 1.217 95% CI 0.407-3.637 p = 0.725; OR 1.068 95% CI 0.359-3.173 p = 0.906). Within two retrieval attempts, mTICI 3 was better than the first retrieval to mTICI 2b. After early mTICI 2b, each retrieval should be undertaken with caution to pursue a higher reperfusion grade.

Stent-retriever characteristics and strategies associated with recanalization in thrombectomy for acute ischemic stroke

IntroductionPredictive factors for successful reperfusion in mechanical thrombectomy for acute ischemic stroke, and especially technical factors, remain controversial. We investigated various techniques for better angiographic outcomes. MethodsIn this retrospective study, acute ischemic stroke patients with large vessel occlusion treated with mechanical thrombectomy with combined technique were included. Scoring of the reperfusion grade for each attempt was conducted, and each attempt was divided into two groups based on successful reperfusion, which was defined using the presence or absence of modified thrombolysis in cerebral infarction 2b–3. The following characteristics were evaluated: the choice of stent-retriever, its length, occlusion site, thrombus position relative to deployed stent-retriever, methods of thrombectomy, and successful advancement of the distal access catheter to the proximal end of the thrombus. ResultsAmong 251 patients who underwent mechanical thrombectomy, 154 patients (255 attempts: mTICI 0–2a group, n = 119; mTICI 2b-3 group, n = 136) were included in the analysis. The thrombus position relative to the deployed stent-retriever was likely associated with successful reperfusion, although it was not statistically significant (proximal two-thirds 56.8 %; distal one-third 44.3 %, p = 0.09). Successful advancement of the distal access catheter was related to successful reperfusion both in univariate analysis (success 57.9 %; fail 35.8 %, p < 0.01) and in multivariate regression analysis (odds ratio 2.45; 95 % confidence interval: 1.30–4.61, p < 0.01). ConclusionsSuccessful advancement of the distal access catheter to the proximal end of thrombus might be a key component for successful reperfusion in mechanical thrombectomy.

Intravenous Thrombolysis Before Thrombectomy Improves Functional Outcome After Stroke Independent of Reperfusion Grade.

We studied the association of bridging intravenous thrombolysis (IVT) before thrombectomy for anterior circulation large-vessel occlusion and functional outcome and scrutinized its dependence on grade of reperfusion and distal thrombus migration. We included consecutive patients withanterior circulation large-vessel occlusion from our prospective registry of thrombectomy-eligible patients treated from January 1, 2017 to January 1, 2023 at a tertiary stroke center in Germany in this retrospective cohort study. To evaluate the association of bridging IVT and functional outcome quantified via modified Rankin Scale score at 90 days we used multivariable logistic and lasso regression including interaction terms with grade of reperfusion quantified via modified Thrombolysis in Cerebral Infarction (mTICI) scale and distal thrombus migration adjusted for demographic and cardiovascular risk profiles, clinical and imaging stroke characteristics, onset-to-recanalization time and distal thrombus migration. We performed sensitivity analysis using propensity score matching. In our study population of 1000 thrombectomy-eligible patients (513 women; median age, 77 years [interquartile range, 67-84]), IVT emerged as a predictor of favorable functional outcome (modified Rankin Scale score, 0-2) independent of modified mTICI score(adjusted odds ratio, 0.49 [95% CI, 0.32-0.75]; P=0.001). In those who underwent thrombectomy (n=812), the association of IVT and favorable functional outcome was reproduced (adjusted odds ratio, 0.49 [95% CI, 0.31-0.74]; P=0.001) and was further confirmed on propensity score analysis, where IVT led to a 0.35-point decrease in 90-day modified Rankin Scale score (ß=-0.35 [95 CI%, -0.68 to 0.01]; P=0.04). The additive benefit of IVT remained independent of modified mTICI score (ß=-1.79 [95% CI, -3.43 to -0.15]; P=0.03) and distal thrombus migration (ß=-0.41 [95% CI, -0.69 to -0.13]; P=0.004) on interaction analysis. Consequently, IVT showed an additive association with functional outcome in the subpopulation of patients undergoing thrombectomy who achieved successful reperfusion (mTICI ≥2b; ß=-0.46 [95% CI, -0.74 to -0.17]; P=0.002) and remained beneficial in those with unsuccessful reperfusion (mTICI ≤2a; ß=-0.47 [95% CI, -0.96 to 0.01]; P=0.05). In thrombectomy-eligible patients with anterior circulation large-vessel occlusion, IVT improves functional outcome independent of grade of reperfusion and distal thrombus migration.

Postprocedural delirium following mechanical thrombectomy for acute ischemic stroke: a retrospective study

IntroductionNational representative estimates on in-hospital delirium after acute ischemic stroke are not well established and there is limited data on the impact of delirium on clinical outcomes following mechanical thrombectomy. We evaluated risk factors for delirium and the impact on outcomes following mechanical thrombectomy for acute ischemic stroke.MethodsThis is a retrospective study of patients who underwent mechanical thrombectomy for acute ischemic stroke at a single tertiary comprehensive stroke center between April 2011 and December 2019. Delirium was assessed using the Confusion Assessment Method for the Intensive Care Unit. Patient characteristics, comorbidities, laboratory data, elapsed times, tissue plasminogen activator use, duration of the procedure, type of anesthesia, National Institute of Health stroke scores (NIHSS), sedation scores, reperfusion grades, complications, length of hospital stay, discharge disposition, and 90-day mortality were evaluated.ResultsFive hundred and two patients were evaluated, and post-procedural delirium was identified in 24/467 (5.1%) patients. Thirty-five patients could not be assessed for delirium due to excessive sedation. The incidence of delirium in white vs. non-white patients &amp;lt;65 years was 5/137 (3.6%) compared to 0/91 (0%), and 7/176 (4.0%) compared to 12/63 (19%) in patients ≥65 years, P = 0.006. Bias reduction multi-variable analysis identified low postprocedural hemoglobin level odds ratio of 0.76 (95% CI 0.61–0.92, P = 0.006), greater age (odds ratio 1.04, 95% CI 1.01–1.009, P = 0.024), and non-white race odds ratio of 2.52 (95% CI 1.06–6.38, P = 0.030) as factors associated with delirium [Brier score = 0.045, C-index = 0.800, and Akaike Information Criterion (AIC) = 174]. General anesthesia was not associated with an increased delirium risk. NIHSS at 24 and 48 h and discharge, length of stay, and 90-day mortality were not different between delirium and no-delirium groups. Delirium patients had a reduced odds ratio of 0.13 (05% CI 0.01–1.00, P = 0.02) for home discharge.DiscussionDelirium following mechanical thrombectomy for acute ischemic stroke primarily affected older patients and was associated with reduced odds of home discharge following hospitalization. Changes in NIHSS during hospitalization and 90-day mortality were not adversely affected by the presence of delirium. General anesthesia was not associated with an increased delirium risk following mechanical thrombectomy.

Abstract WMP5: Intravenous Thrombolysis Before Thrombectomy Improves Functional Outcome After Stroke Independent of Reperfusion Grade

Background: We studied the effect of intravenous thrombolysis (IVT) before thrombectomy for anterior circulation large vessel occlusion (acLVO) on functional outcome and scrutinized its dependence on grade of reperfusion and distal thrombus migration. Methods: We included consecutive acLVO patients from our prospective registry of thrombectomy-eligible patients treated from 01/01/2017 to 01/01/2023 at a tertiary stroke center in Germany into a retrospective cohort study. We evaluated the effects of IVT on functional outcome quantified via modified Rankin scale (mRS) at 90 days applying multivariable logistic and lasso regression including interaction terms with grade of reperfusion quantified via modified Thrombolysis in Cerebral Infarction (mTICI) scale and distal thrombus migration adjusted for demographic and cardiovascular risk profiles, clinical and imaging stroke characteristics and onset-to-recanalization time. We performed sensitivity analysis using propensity score matching. Results: In our study population of 1000 thrombectomy-eligible patients (513 females, median age 77 [67-84, interquartile range]) IVT emerged as predictor of favorable functional outcome (mRS 0-2) independent of mTICI (adjusted OR 0.49; 95% CI [0.32;0.75]; p=0.001). In those who underwent thrombectomy (n=812) the association of IVT and favorable functional outcome was reproduced (adjusted OR 0.49; 95% CI [0.31;0.74]; p=0.001) and was further confirmed on propensity score analysis where IVT led to a 0.35-point decrease in 90-day mRS score [ß=-0.35; 95CI% [-0.68;-0.01]; p=0.04]. The additive benefit of IVT remained independent of mTICI (ß=-1.79; 95% CI [-3.43;-0.15]; p=0.03) and distal thrombus migration (ß=-0.41; 95% CI [-0.69;-0.13]; p=0.004) on interaction analysis. Consequently, IVT showed an additive effect on functional outcome in the subpopulation of thrombectomy patients who achieved successful reperfusion (TICI≥2b; ß=-0.46; 95% CI [-0.74;-0.17]; p=0.002) and remained beneficial in those with unsuccessful reperfusion (TICI≤2a; ß=-0.47; 95% CI [-0.96;-0.01]; p=0.05). Conclusions: In thrombectomy-eligible acLVO patients IVT improves functional outcome independent of grade of reperfusion and distal thrombus migration.

Abstract WP204: Impact of Reperfusion Grade and First Pass Effect in Large vs Small Core Patients Undergoing Mechanical Thrombectomy

Introduction: While patients with small core stroke (SCS) and large core stroke(LCS) benefit from Mechanical Thrombectomy(MT), the impact of reperfusion (Thrombolysis in Cerebral Infarction (eTICI) grade and the first pass effect (FPE)) on clinical outcomes remains poorly understood. We aim to study the interplay between these factors in LCS and SCS patients. Methodology: Retrospective analysis of a comprehensive stroke center prospective database for patients with MCA-M1 or ICA-T occlusions who underwent MT between November 2010-March 2023. Logistic regression models assessed ASPECTS and eTICI score relationships and their impact on outcomes, adjusted for age, NIHSS, tPA, hypertension, general anesthesia and clot location. Results: Of 1548 included patients (mean age 65±16 years, 50.0% males)Table 1, 9.1%(141/1548) were categorized as a LCS (ASPECTS 0-5: 3.5% ASPECTS 0-2 and 96.0% 3-5) while 90.9%(1407/1548) as a SMC (53.0% ASPECTS 6-8 and 47.0% ASPECTS 9-10)(Table1). Lower rates of FPE were achieved in the LCS cohort (26%) compared to the SCS cohort (36%). First pass effect had comparable relative impact on independence rates on LCS and SCS (Figure1A; p&gt;0.05). Final reperfusion rates were comparable LCS and SCS cohorts; In LCS, 5%, 11%, 26%, and 49% achieved eTICI grades 0-2a, 2b50, 2b67, and 2c-3, while in SCS, the percentages were 5.3%, 11%, 18%, and 66%. The relative benefit of final eTICI2c-3 vs 2b50 was comparable between LCS and SCS (p&gt;0.05;Figure1B) Conclusion: The magnitude of benefit of achieving FPE as well as final full reperfusion (eTICI2c-3 vs eTICI2b) is comparable in large and smaller core strokes.

Abstract WP212: Site vs. Core Lab Adjudicated eTICI Scores Compared During Off and Normal Hours - Insights From the ASSIST Registry

Introduction: The ASSIST registry is a prospective, global registry whose primary aim was to identify which endovascular technique yields the highest rate of first pass TICI 2C reperfusion. Data from this registry was analyzed for this secondary analysis to assess if site adjudicated eTICI scores differ from the core lab during off hours [7 PM to 6:59 AM plus weekends (7 PM Friday - 6:59 AM Monday)] compared to normal hours (7 AM - 6:59 PM on weekdays). An additional objective is to assess if outcomes are worse with regards to core-lab adjudicated reperfusion grades and mRS 0-2 in procedures performed during off hours. Methods: Details from the ASSIST registry have been previously presented. Descriptive statistics for outcomes and percent agreement between core-lab and site-reported eTICI were calculated. Regression models were performed for first pass treatment of target occlusion resulting in ≥ 2c by core-lab, mRS 0-2 at 90 days, and whether first pass eTICI agreed for both core-lab and site-reported. Results: A total of 1318 patients were included in the analysis with 652 patients presenting during normal hours and 666 patients presenting during off hours. Overall, agreement between core-lab and site-reported eTICI at first pass occurred in 86.7% and 78.5% for final eTICI ≥2c. Agreement occurred for first pass eTICI ≥2c 87.2% during normal hours and 86.1% during off hours. Agreement occurred less often on final pass eTICI ≥2c during both normal and off hours (77.7% and 79.3%, respectively). Good functional outcomes based on 90-day mRS 0-2 occurred in 55.5% in patients presenting during normal hours and 53.8% in patients presenting during off hours. Off-hour vs. normal hour procedures was not significantly associated with first pass efficacy, mRS 0-2 at 90 days, or whether first pass eTICI agreed for both core-lab and site-reported in adjusted regression analyses. Conclusions: There was a higher level of agreement between core-lab and site-reported first pass eTICI scores during all hours while agreement occurred less often for final reperfusion. These results suggest a high level of correlation with site adjudicated and core lab adjudicated successful reperfusion grading. ClinicalTrials.gov ID: NCT03845491

Competitive leptomeningeal flow impact on thrombectomy reperfusion grade rating

BackgroundCompetitive leptomeningeal flow (CLF) can be observed immediately after mechanical thrombectomy (MT) reperfusion with retrograde contrast clearing of the distal leptomeningeal branches from non-contrast opacified flow through different vascular territories....

Abstract WP141: Leptomeningeal Competitive Flow Impact on Thrombectomy Reperfusion Grade Rating

Background: The extent of reperfusion following thrombectomy (MT) for large vessel occlusion strokes is predictive of outcomes. There is still inter-rater variability in the reperfusion scoring. We noticed that some patients present with retrograde contrast clearing of the distal branches from non-contrast-opacified flow originated from different territories. We aim to evaluate the frequency of this phenomenon (“competitive flow” (CF)), to evaluate if it has an association with the degree of leptomeningeal collaterals, and its impact on eTICI score. Methods: This is a retrospective-analysis of our MT database spanning 11/2020-12/2021. We included consecutive cases of intracranial internal carotid (i-ICA) and middle cerebral artery (MCA) M1 occlusions. CF was defined by the observation of retrograde clearing of distal MCA branches that were previously opacified by antegrade reperfusion. The clearance of the distal branches is presumed to occur due to CF via non-contrast-opacified PCA or ACA flow. The washout was considered CF if it cleared abruptly with or without forward reconstitution of antegrade opacification. Results: We included a 125 patients. Median age was 64years, 51%were males. Baseline median NIHSS was 17 and ASPECTS 9. Median last-known-well-time to puncture was 7 hours, 30.4% received tPA. Final eTICI2c-3 was achieved in 81.6%. CF was present in 32(25.6%)patients. Baseline characteristics were similar between both groups. The CF arm had better leptomeningeal single-phase-CTA-collaterals(p=0.01) and smaller CTP malignant hypoperfusion volume(p=0.06) VS non-CF. The inter-rater-agreement for eTICI score was moderate when CF was present and excellent in its absence (Krippendorf’s alpha=0.65 and 0.81,respectively). There was poor agreement (K-value=0.3) for the presence versus absence of CF between both operators. Reviewer 1 (2-year-post-training) had correctly identified 46% of patients with consensus CF vs 90% to Reviewer 2 (9-year-post-training) after the consensus read. Conclusion: CF was observed in 32% of patients. CF was found to be associated with better collateral flow, and to impact the reported procedural eTICI rating.

Abstract 073: Thrombectomy Alone Versus Bridging Intravenous Alteplase in A US Population: Regression Discontinuity Analysis

Introduction Recent randomized controlled trials (RCT) failed to demonstrate the non‐inferiority of skipping IV tPA in patients with planned endovascular therapy (EVT). None of these studies included patients from the US due to regulatory challenges. Given that practice patterns vary relative to Asia, Australia, and Europe, we sought to address this topic using a validated alternative to RCTs, regression discontinuity (RD). Methods From the prospectively collected SVIN Registry encompassing all consecutive patients treated with EVT from 12 centers across the US, we identified patients from 12/2010 – 12/2021. RD design achieves quasi‐randomization and can determine causal effects by analyzing subjects on immediately adjacent sides of a cutoff. Here, we take advantage of the sharp drop in the likelihood of IV tPA treatment at the 4.5‐hour mark from the patients’ last known well time. Subjects immediately on either side of the cutoff have markedly different probabilities of receiving the treatment while sharing similar characteristics in other relevant aspects. Patients were excluded if they underwent EVT after inter‐hospital transfer, were inpatient at the time of acute ischemic stroke (AIS), received IV tPA outside the 4.5‐hour window, or were treated with EVT after the 10‐hour window, as these patients would not contribute to the RD analysis. The primary outcome was a good functional outcome defined as 90‐day mRS 0‐2 and was analyzed using validated RD analysis methods with local linear regressions and triangular kernel weights. Secondary endpoints included rates of symptomatic intracranial hemorrhage and substantial reperfusion. Results Among 961 patients who met inclusion criteria, all 12 EVT centers within the SVIN Registry were represented. The median age was 70 [IQR 58‐79], 48% were female, NIHSS was 17, and the most common occlusion location was M1 MCA (45%). There were no substantial differences in presentation characteristics between patients treated with IV tPA and without. We observed a significant fall (30%) in the probability of tPA around the cutoff time of 235 minutes from the last known well to hospital arrival (allowing 35 minutes for in‐hospital evaluation from the 4.5‐hour cutoff), while there were no significant differences in other relevant features including age, NIHSS, ASPECTS, and final reperfusion grade at the cutoff, validating the underlying RD assumptions (Figure A). In RD analysis, we observed no association between IV tPA treatment and functional independence at 90‐days in patients undergoing EVT (risk difference ‐0.29 (95% CI [‐2.75 to 2.15]) (Figure B), nor in the secondary outcomes of excellent outcomes (mRS 0‐1) at 90 days, mortality, symptomatic ICH or first pass reperfusion. Conclusion Here, we perform what we believe to be the strongest study to date examining the benefit of IV tPA in patients undergoing EVT for LVO AIS in a US‐based cohort, and we find no evidence of association with 90‐day functional independence, consistent with findings of RCTs performed outside the US.

Long-Term Effect of Mechanical Thrombectomy in Stroke Patients According to Advanced Imaging Characteristics.

Data on long-term effect of mechanical thrombectomy (MT) in patients with large ischemic cores (≥ 70 ml) are scarce. Our study aimed to assess the long-term outcomes in MT-patients according to baseline advanced imaging parameters. We performed asingle-centre retrospective cohort study of stroke patients receiving MT between January 1, 2010 and December 31, 2018. We assessed baseline imaging to determine core and mismatch volumes and hypoperfusion intensity ratio (with low ratio reflecting good collateral status) using RAPID automated post-processing software. Main outcomes were cross-sectional long-term mortality, functional outcome and quality of life by May 2020. Analysis were stratified by the final reperfusion status. In total 519 patients were included of whom 288 (55.5%) have deceased at follow-up (median follow-up time28months, interquartile range 1-55). Successful reperfusion was associated with lower long-term mortality in patients with ischemic core volumes ≥ 70 ml (adjusted hazard ratio (aHR) 0.20; 95% confidence interval (95% CI) 0.10-0.44) and ≥ 100 ml (aHR 0.26; 95% CI 0.08-0.87). The effect of successful reperfusion on long-term mortality was significant only in the presence of relevant mismatch (aHR 0.17; 95% CI 0.01-0.44). Increasing reperfusion grade was associated with ahigher rate of favorable outcomes (mRS 0-3) also in patients with ischemic core volume ≥ 70 ml (aOR 3.58, 95% CI 1.64-7.83). Our study demonstrated asustainable benefit of better reperfusion status in patients with large ischemic core volumes. Our results suggest that patient deselection based on large ischemic cores alone is not advisable.

Development and Validation of a Postprocedural Model to Predict Outcome After Endovascular Treatment for Ischemic Stroke

Outcome prediction after endovascular treatment (EVT) for ischemic stroke is important to patients, family members, and physicians. To develop and validate a model based on preprocedural and postprocedural characteristics to predict functional outcome for individual patients after EVT. A prediction model was developed using individual patient data from 7 randomized clinical trials, performed between December 2010 and December 2014. The model was developed within the Highly Effective Reperfusion Evaluated in Multiple Endovascular Stroke Trials (HERMES) collaboration and external validation in data from the Dutch Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands (MR CLEAN) Registry of patients treated in clinical practice between March 2014 and November 2017. Participants included patients from multiple centers throughout different countries in Europe, North America, East Asia, and Oceania (derivation cohort), and multiple centers in the Netherlands (validation cohort). Included were adult patients with a history of ischemic stroke from an intracranial large vessel occlusion in the anterior circulation who underwent EVT within 12 hours of symptom onset or last seen well. Data were last analyzed in July 2022. A total of 19 variables were assessed by multivariable ordinal regression to predict functional outcome (modified Rankin Scale [mRS] score) 90 days after EVT. Variables were routinely available 1 day after EVT. Akaike information criterion (AIC) was used to optimize model fit vs model complexity. Probabilities for functional independence (mRS 0-2) and survival (mRS 0-5) were derived from the ordinal model. Model performance was expressed with discrimination (C statistic) and calibration. A total of 781 patients (median [IQR] age, 67 [57-76] years; 414 men [53%]) constituted the derivation cohort, and 3260 patients (median [IQR] age, 72 [61-80] years; 1684 men [52%]) composed the validation cohort. Nine variables were included in the model: age, baseline National Institutes of Health Stroke Scale (NIHSS) score, prestroke mRS score, history of diabetes, occlusion location, collateral score, reperfusion grade, NIHSS score at 24 hours, and symptomatic intracranial hemorrhage 24 hours after EVT. External validation in the MR CLEAN Registry showed excellent discriminative ability for functional independence (C statistic, 0.91; 95% CI, 0.90-0.92) and survival (0.89; 95% CI, 0.88-0.90). The proportion of functional independence in the MR CLEAN Registry was systematically higher than predicted by the model (41% vs 34%), whereas observed and predicted survival were similar (72% vs 75%). The model was updated and implemented for clinical use. The prognostic tool MR PREDICTS@24H can be applied 1 day after EVT to accurately predict functional outcome for individual patients at 90 days and to provide reliable outcome expectations and personalize follow-up and rehabilitation plans. It will need further validation and updating for contemporary patients.

Critical evaluation of the modified Rankin Scale for assessment of the efficacy of mechanical thrombectomy: A retrospective comparison between the modified Rankin Scale and functional independence measure.

The primary outcome measure used in mechanical thrombectomy (MT) trials is the modified Rankin Scale (mRS). However, the accuracy of mRS might be limited. On the other hand, the functional independence measure (FIM) is a widely used tool to quantify the extent to which patients require assistance during their activities of daily living. The current study aimed to reveal different clinical backgrounds that affect the efficacy of MT measured either by mRS or FIM. Patients who underwent MT at our institution from January 2019 to July 2022 were included and divided into groups based on mRS scores of 0-2 and ≥ 3. Patients were also divided into two groups based on a cut-off value of FIM of ≥ 108, as patients with FIM ≥ 108 are capable of living an independent life. The mRS score was 0-2 in 33% of the patients, while the FIM score was ≥ 108 in only 15% of the patients. In the mRS groups, there were significant differences in terms of duration of hospitalization, National Institutes of Health Stroke Scale (NIHSS) scores, achievement of thrombolysis in cerebral infarction (TICI) reperfusion grade of 2b or 3, and postoperative bleeding. Multivariate logistic regression analysis revealed that NIHSS score and achievement of TICI 2b or 3 were significant factors related to mRS 0-2 at discharge. The FIM groups differed significantly in terms of age and, duration of hospitalization, NIHSS score, although multivariate logistic regression analysis revealed that only the NIHSS score was significantly associated with an FIM score of ≥ 108. The study showed that the percentage of independent patients is significantly reduced when we evaluated the patients by the FIM. In addition, there are some differences in the clinical background that led to a good outcome between that evaluated by mRS and FIM.

The effect of intravenous thrombolysis on patients with successful thrombectomy depends on final reperfusion grade: A retrospective study.

Although intravenous thrombolysis (IVT) has not shown confirmative effects on the outcomes of patients receiving successful thrombectomy, it might influence the outcomes of a subset of these patients. This study aims to evaluate whether the effects of IVT depend on final reperfusion grade in patients with successful thrombectomy. This is a single-center, retrospective analysis of patients with an acute anterior circulation large-vessel occlusion and a successful thrombectomy between January 2020 and June 2022. Final reperfusion grade was evaluated by the modified Thrombolysis in Cerebral Infarction (mTICI) score, which was dichotomized into incomplete (mTICI 2b) and complete (mTICI 3) reperfusion. The primary outcome was functional independence (90-day modified Rankin Scale score 0-2). Safety outcomes were 24-h symptomatic intracranial hemorrhage and 90-day all-cause mortality. Multivariable logistic regression analyses were used to assess the interactions between IVT treatment and final reperfusion grade on outcomes. When comparing all 167 patients enrolled in the study, IVT did not influence the extent of functional independence (adjusted OR: 1.38; 95% CI: 0.65-2.95; p = 0.397). The effect of IVT on functional independence depended on final reperfusion grade (p = 0.016). IVT benefited patients with incomplete reperfusion (adjusted OR: 3.70; 95% CI 1.21-11.30; p = 0.022), but not those with complete reperfusion (adjusted OR: 0.48, 95% CI: 0.14-1.59; p = 0.229). IVT was not associated with 24-h symptomatic intracerebral hemorrhage (p = 0.190) or 90-day all-cause mortality (p = 0.545). The effect of IVT on functional independence depended on final reperfusion grade in patients with successful thrombectomy. IVT appeared to benefit patients with incomplete reperfusion, but not those with complete reperfusion. Because reperfusion grade cannot be determined prior to endovascular treatment, this study argues against withholding IVT in IVT-eligible patients.

Endovascular Stroke Therapy for Posterior Circulation Acute Ischemic Stroke Has Diminishing Benefit with Additional Passes

Background The relationship between pass number during endovascular stroke therapy (EST) and outcomes in anterior circulation large vessel occlusion (LVO) acute ischemic stroke (AIS) has been well studied. However, the association between EST attempts and outcomes for patients with posterior circulation LVO remains unclear. Methods From our prospectively maintained multicenter registry, we identified consecutive patients with LVO AIS who underwent EST. The number of thrombectomy passes and per‐pass reperfusion grades (thrombolysis in cerebral infarction) were recorded prospectively at the time of procedure. The primary outcome was the association of number of EST passes and functional independence (modified Rankin scale 0–2) at 90 days. Secondary outcomes included likelihood of attaining substantial reperfusion (thrombolysis in cerebral infarction 2b‐3). Results Among 894 patients with LVO AIS who underwent EST, median age was 68 [interquartile range 58–78], 49% were female, and median National Institutes of Health Stroke Scale was 16 [interquartile range 11–21]. Of this cohort, 86 (9.6%) had posterior circulation LVO, including 65 (7%) with basilar artery occlusion and 9 (1%) with vertebral artery occlusion. The diminishing benefit on successful reperfusion of additional passes was similar for anterior and posterior circulation AIS. Among patients with posterior circulation stroke, successful reperfusion with fewer passes was associated with greater likelihood of good functional outcome at 90 days (40.0% versus 4.8% modified Rankin scale 0–2 with 1–2 versus 3+ passes; P = 0.003). The likelihood of good outcome in patients with posterior circulation LVO treated with EST and successful reperfusion in 1–2 passes was comparable to patients with anterior circulation LVO (40.0% versus 40.2%, posterior versus anterior; P = 0.553). Conclusions The number of EST passes has a significant association with functional independence at 90 days for patients with posterior circulation LVO AIS. After 2 passes, there is significantly reduced benefit conferred by additional passes. Overall clinical outcomes in patients with successful reperfusion with 1–2 passes were similar in patients with posterior circulation compared with anterior circulation LVO.

Endovascular Thrombectomy with or without Intravenous Thrombolysis for Anterior Circulation Large Vessel Occlusion in the Imperial College London Thrombectomy Registry.

Background and purpose. Mechanical thrombectomy (MT) is the standard of care for eligible patients with a large vessel occlusion (LVO) acute ischemic stroke. Among patients undergoing MT there has been uncertainty regarding the role of intravenous thrombolysis (IVT) and previous trials have yielded conflicting results regarding clinical outcomes. We aim to investigate clinical, reperfusion outcomes and safety of MT with or without IVT for ischemic stroke due to anterior circulation LVO. Materials and Methods. This observational, prospective, single-centre study included consecutive patients with acute LVO ischemic stroke of the anterior circulation. The primary outcomes were the rate of in-hospital mortality, symptomatic intracranial haemorrhage and functional independence (mRS 0-2 at 90 days). Results. We enrolled a total of 577 consecutive patients: 161 (27.9%) were treated with MT alone while 416 (72.1%) underwent IVT and MT. Patients with MT who were treated with IVT had lower rates of in-hospital mortality (p = 0.037), higher TICI reperfusion grades (p = 0.007), similar rates of symptomatic intracranial haemorrhage (p = 0.317) and a higher percentage of functional independence mRS (0-2) at 90 days (p = 0.022). Bridging IVT with MT compared to MT alone was independently associated with a favorable post-intervention TICI score (>2b) (OR, 1.716; 95% CI, 1.076-2.735, p = 0.023). Conclusions. Our findings suggest that combined treatment with MT and IVT is safe and results in increased reperfusion rates as compared to MT alone.

Abstract WMP93: Additional Endovascular Thrombectomy Passes After An Initial TICI2b Reperfusion To Improve Final Reperfusion Grade Does Not Improve Functional Outcomes

Background: First pass complete or near complete reperfusion defined as a modified Thrombolysis in Cerebral Infarction (mTICI) 2c/3 is the target for endovascular thrombectomy (EVT). Here, we examine whether additional passes in patients who achieve a first pass mTICI 2b, in order to attain mTICI 2c/3, improve clinical outcomes. Methods: From our prospectively maintained institutional registry at 4 comprehensive stroke centers, we identified patients treated with EVT (11/2017-12/2021). Per-pass mTICI grades were recorded at the time of the procedure. The primary outcome was functional independence rates at 90 days (mRS 0-2) in first pass mTICI 2b patients compared with multiple passes mTICI 2c/3 patients. Results: A total of 857 EVT patients were identified in the study period. The median age was 68 [58-79], 49.7% were female, median NIHSS was 16 [11-21], median ASPECTS was 9 [7-10], and 64% had MCA occlusions. First pass mTICI 2c/3 (FP-mTICI 2c/3) was achieved in 342 (39.9%) cases and first pass mTICI 2b (FP-mTICI 2b) was achieved in 123 (14.4%) patients. Of the FP-mTICI 2b group, 27 (21.9%) patients received additional passes to reach complete reperfusion. Good functional outcome was observed in 159 patients (46.5%) of the FP-mTICI 2c/3 reperfusion group as compared to 27 patients (28.1%) in the FP-mTICI 2b group (p=0.002). The rate of good functional outcome was not significantly different for patients who achieved mTICI 2c/3 following additional passes after a first pass mTICI 2b (28.1 vs. 29.6%, first pass mTICI 2b vs. first pass mTICI 2b with final mTICI 2c/3, p=0.954). Adjusted for age, sex and NIHSS at presentation, patients with FP-mTICI 2c/3 had a better chance of good outcomes than patients with FP-mTICI 2b (OR 2.23, 95% CI [1.38-3.62]). In multivariable analysis adjusting for age, sex, and NIHSS at presentation, patients with FP-mTICI 2b reperfusion followed by improved reperfusion to mTICI 2c/3 did not have better outcomes than patients with FP-mTICI 2b reperfusion (OR 1.14, 95% CI [0.41-3.12]). Conclusions: Additional EVT passes to achieve mTICI 2c/3 following a first pass mTICI 2b does not lead to significant improvement in functional outcomes. This study suggests that EVT can be terminated if FP-mTICI 2b-3 is achieved.

Clinical effect of successful reperfusion in patients presenting with NIHSS < 6 and large vessel occlusion

PurposeThe purpose of this study was to evaluate the impact of reperfusion in patients with large vessel occlusion (LVO) of the anterior circulation and National Institutes of Health Stroke Scale (NIHSS)< 6. MethodsIt was a retrospective cohort study. The reperfusion grade was determined using the modified thrombolysis in cerebral infarction (TICI) score. The modified Rankin Score (mRS) ≤1 were defined as excellent and (mRS) ≤2 as favorable outcome at 3-month. Meanwhile, the all-cause mortality, intracerebral hemorrhage, and complications were recorded. Multivariate logistic regression analyses were performed to evaluate outcomes. ResultsSeventy-six patients (86.4%) achieved reperfusion (TICI2B/3). Excellent outcome was achieved in 62 (70.5%) and favorable outcome in 69 (78.4%). All-cause death occurred in 2 (2.3%). The rate of excellent outcome in patients with TICI0,1,2A was 41.7%, with TICI2B 69.2%, and with TICI3 78.0% (p < 0.05). In a multivariate logistic regression analysis related to excellent outcome, the OR(95% CI) was 5.68(1.35,23.95) for TICI3; the test for linear trend by entering categorical variables as continuous variables in the adjusted model (p for trend=0.02<0.05), defining TICI0,1,2A as reference. Subgroup analyses showed without intravenous thrombolysis (IVT) (OR, 14.29; 95% CI, 1.76–116.37) and with middle cerebral artery (MCA) occlusion (OR, 7.97; 95% CI,1.26–50.32), the excellent outcome further improved with TICI3. Findings were similar in favorable outcome. ConclusionsOur results indicated that successful reperfusion was intensely connected with better functional outcomes for patients with LVO presenting with NIHSS<6 in the anterior circulation, especially MCA occlusion and pretreatment without IVT.