Non-contrast CT radiomics-clinical machine learning model for futile recanalization after endovascular treatment in anterior circulation acute ischemic stroke.

OBJECTIVE: To establish a machine learning model based on radiomics and clinical features derived from non-contrast CT to predict futile recanalization (FR) in patients with anterior circulation acute ischemic stroke (AIS) undergoing endovascular treatment. METHODS: A retrospective analysis was conducted on 174 patients who underwent endovascular treatment for acute anterior circulation ischemic stroke between January 2020 and December 2023. FR was defined as successful recanalization but poor prognosis at 90 days (modified Rankin Scale, mRS 4-6). Radiomic features were extracted from non-contrast CT and selected using the least absolute shrinkage and selection operator (LASSO) regression method. Logistic regression (LR) model was used to build models based on radiomic and clinical features. A radiomics-clinical nomogram model was developed, and the predictive performance of the models was evaluated using area under the curve (AUC), accuracy, sensitivity, and specificity. RESULTS: A total of 174 patients were included. 2016 radiomic features were extracted from non-contrast CT, and 9 features were selected to build the radiomics model. Univariate and stepwise multivariate analyses identified admission NIHSS score, hemorrhagic transformation, NLR, and admission blood glucose as independent factors for building the clinical model. The AUC of the radiomics-clinical nomogram model in the training and testing cohorts were 0.860 (95%CI 0.801-0.919) and 0.775 (95%CI 0.605-0.945), respectively. CONCLUSION: The radiomics-clinical nomogram model based on non-contrast CT demonstrated satisfactory performance in predicting futile recanalization in patients with anterior circulation acute ischemic stroke.

Predictors of futile recanalization after endovascular treatment of acute ischemic stroke.

OBJECTIVE: Endovascular therapy (EVT) is the most successful treatment for patients with acute ischemic stroke (AIS) due to large vessel occlusion (LVO) in the anterior circulation. However, futile recanalization (FR) seriously affects the prognosis of these patients. The aim of this study was to investigate predictors of FR after EVT in patients with AIS. METHOD: Patients diagnosed with AIS due to anterior circulation LVO and receiving EVT between June 2020 and October 2022 were prospectively enrolled. FR after EVT was defined as a poor 90-day prognosis (modified Rankin Scale [mRS] score ≥ 3) despite achieving successful reperfusion (modified Thrombolysis in Cerebral Infarction [mTICI] classification of 2b-3). All included patients were categorized into control group (mRS score < 3) and FR group (mRS score ≥ 3). Demographic characteristics, comorbidities (hypertension, diabetes, atrial fibrillation, smoking, etc.), stroke-specific data (NIHSS score, ASPECT score and site of occlusion), procedure data (treatment type [direct thrombectomy vs. bridging thrombectomy], degree of vascular recanalization [mTICI], procedure duration time and onset-recanalization time), laboratory indicators (lymphocytes count, neutrophils count, monocytes count, C-reactive protein, neutrophil-to-lymphocyte ratio [NLR], monocyte-to-high-density lipoprotein ratio [MHR], lymphocyte-to-monocyte ratio [LMR], lymphocyte-to-C-reactive protein ratio [LCR], lymphocyte-to-high-density lipoprotein ratio[LHR], total cholesterol and triglycerides.) were compared between the two groups. Multivariate logistic regression analysis was performed to explore independent predictors of FR after EVT. RESULTS: A total of 196 patients were included in this study, among which 57 patients were included in the control group and 139 patients were included in the FR group. Age, proportion of patients with hypertension and diabetes mellitus, median NIHSS score, CRP level, procedure duration time, neutrophil count and NLR were higher in the FR group than in the control group. Lymphocyte count, LMR, and LCR were lower in the FR group than in the control group. There were no significant differences in platelet count, monocytes count, total cholesterol, triglycerides, HDL, LDL, gender, smoking, atrial fibrillation, percentage of occluded sites, onset-recanalization time, ASPECT score and type of treatment between the two groups. Multivariate logistic regression analysis demonstrated that NLR was independently associated with FR after EVT (OR = 1.37, 95%CI = 1.005-1.86, P = 0.046). CONCLUSION: This study demonstrated that high NLR was associated with a risk of FR in patients with AIS due to anterior circulation LVO. These findings may help clinicians determine which patients with AIS are at higher risk of FR after EVT. Our study can provide a theoretical basis for interventions in the aforementioned population.

Introducing the Futile Recanalization Prediction Score (FRPS): A Novel Approach to Predict and Mitigate Ineffective Recanalization after Endovascular Treatment of Acute Ischemic Stroke.

Objective: This study aims to develop and validate the Futile Recanalization Prediction Score (FRPS), a novel tool designed to predict the severity risk of FR and aid in pre- and post-EVT risk assessments. Methods: The FRPS was developed using a rigorous process involving the selection of predictor variables based on clinical relevance and potential impact. Initial equations were derived from previous meta-analyses and refined using various statistical techniques. We employed machine learning algorithms, specifically random forest regression, to capture nonlinear relationships and enhance model performance. Cross-validation with five folds was used to assess generalizability and model fit. Results: The final FRPS model included variables such as age, sex, atrial fibrillation (AF), hypertension (HTN), diabetes mellitus (DM), hyperlipidemia, cognitive impairment, pre-stroke modified Rankin Scale (mRS), systolic blood pressure (SBP), onset-to-puncture time, sICH, and NIHSS score. The random forest model achieved a mean R-squared value of approximately 0.992. Severity ranges for FRPS scores were defined as mild (FRPS < 66), moderate (FRPS 66-80), and severe (FRPS > 80). Conclusions: The FRPS provides valuable insights for treatment planning and patient management by predicting the severity risk of FR. This tool may improve the identification of candidates most likely to benefit from EVT and enhance prognostic accuracy post-EVT. Further clinical validation in diverse settings is warranted to assess its effectiveness and reliability.

Predictors of futile recanalization in nonagenarians treated with mechanical thrombectomy: a multi-center observational study.

BACKGROUND: There is a lack of data regarding patients aged 90 years or older undergoing mechanical thrombectomy and their predictors of futile recanalization. AIMS: We sought to evaluate the predictors of futile recanalization in patients ≥ 90 years with large vessel occlusion undergoing mechanical thrombectomy. METHODS: This multi-center observational retrospective study included patients ≥ 90 years consecutively treated with mechanical thrombectomy in four thrombectomy capable centers between January 1st, 2016 and 30th March 2023. Futile recanalization was defined as large vessel occlusion patients experiencing a 90-day poor outcome (mRS 3-6) despite successful recanalization (mTICI ≥ 2b) after mechanical thrombectomy. RESULTS: Our cohort included 139 patients ≥ 90 years with acute ischemic stroke due to anterior circulation large vessel occlusion treated with mechanical thrombectomy. One hundred seventeen of one hundred thirty-nine patients ≥ 90 years who achieved successful recanalization were included in the analysis (seventy-six female (64.9%)), of whom thirty-one (26.49%) experienced effective recanalization and eighty-six (73.51%) experienced futile recanalization. Patients with futile recanalization had higher NIHSS on admission (p < 0.001); they were less frequently treated with intravenous thrombolysis (p = 0.048), had more often general anesthesia (p = 0.011), and longer door to groin puncture delay (p = 0.002). Univariable regression analysis showed that use of intravenous thrombolysis (0.29, 95% CI 0.02-0.79, p = 0.034) and site of occlusion distal vs proximal (0.34, 95% CI 0.11-0.97, p = 0.044) were associated with reduced probability of futile recanalization while NIHSS on admission (1.29, 95% CI 1.16-1.45, p < 0.001), NIHSS at 24 h (1.15, 95% CI 1.07-1.25, p = 0.002), type of anesthesia used (4.18, 95% CI 1.57-11.08, p = 0.004), and door to groin puncture time (1.02, 95% CI 1.00-1.05, p = 0.005) were associated with increased probability of futile recanalization. Multivariable regression analysis showed that use of intravenous thrombolysis (0.44, 95% CI 0.09-0.88, p = 0.039) was associated with reduced probability of futile recanalization. CONCLUSION: Our study seems to suggest that mechanical thrombectomy with intravenous thrombolysis is associated with reduced probability of futile recanalization in a multi-center cohort of patients aged 90 years or older.

CBF Profile in Computed Tomography Perfusion-Based AutoMIStar Software Predicts Futile Recanalization After Basilar Artery Thrombectomy.

Background: Futile recanalization (FR) remains a significant challenge in patients with acute basilar artery occlusion (BAO) following successful endovascular treatment (EVT). This study aimed to investigate the predictive value of computed tomography perfusion (CTP)-based software (AutoMIStar; Apollo) for FR among BAO patients undergoing EVT. Methods: We analyzed a prospectively maintained database to identify consecutive BAO patients who achieved successful recanalization (modified Thrombolysis in Cerebral Infarction grade ≥ 2b) after EVT between January 2020 and September 2022. Clinical characteristics and imaging parameters from non-contrast CT, CT angiography, and CTP-AutoMIStar were collected for analysis. FR was defined as an unfavorable outcome (modified Rankin Scale score > 3) at 90 days despite successful recanalization. Multivariable stepwise logistic regression analysis was performed to identify independent predictors of FR. Results: Of the 54 patients included in this study, 24 (44.4%) experienced FR. In the univariate analysis, admission National Institutes of Health Stroke Scale score, posterior circulation Acute Stroke Prognosis Early CT Score, Basilar Artery on Computed Tomography Angiography (BATMAN) score, hypoperfusion intensity ratio, and perfusion deficit volume in delay time (DT) > 4 s, DT > 6 s, DT > 8 s, and all cerebral blood flow (CBF) thresholds were associated with FR (all P < 0.05). In the multivariate analysis, perfusion deficit volume in CBF < 35% (adjusted odds ratio [aOR] = 1.105, 95% confidence interval [CI]: 1.004-1.215; P = 0.040) and BATMAN score (aOR = 0.662, 95% CI: 0.455-0.964; P = 0.031) remained independent predictors of FR. Conclusion: Perfusion deficit volume in CBF < 35% on CTP-AutoMIStar imaging maps and BATMAN score are independent predictors of FR after EVT in BAO patients. There is a significant positive correlation between perfusion deficit volume in CBF < 35% and the occurrence of FR.

A novel nomogram to predict futile recanalization in patients with acute ischemic stroke undergoing mechanical thrombectomy.

Background and objective: Futile recanalization (FR) is defined as patients with acute ischemic stroke (AIS) due to large vessel occlusion who still exhibits functional dependence although undergoing successful mechanical thrombectomy (MT). We aimed to develop and validate a simple nomogram for predicting the probability of FR after MT treatment in AIS patients. Methods: Clinical data of AIS patients in the Jrecan clinical trial in China from March 2018 to June 2019 were collected as the derivation set (n = 162). Meanwhile, clinical data of AIS patients who underwent MT in Baotou Central Hospital and Ningbo No.2 Hospital from 2019 to 2021 were collected as the validation set (n = 170). Multivariate logistic regression analysis was performed for all variables that had p < 0.2 in the univariate analysis in the derivation set. The independent risk factors of FR were further screened out and a nomogram was constructed. The performance of the nomogram was analyzed in the derivation and validation set using C-index, calibration plots, and decision curves. Results: No significant difference in FR rate was detected between the derivation set and the validation set [88/162 (54.32%) and 82/170 (48.23%), p = 0.267]. Multivariate logistic regression analysis showed that age ≥ 65 years old (OR = 2.096, 95%CI 1.024-4.289, p = 0.043), systolic blood pressure (SBP) ≥ 180 mmHg (OR = 5.624, 95%CI 1.141-27.717, p = 0.034), onset to recanalization time (OTR) ≥ 453 min (OR = 2.759, 95%CI 1.323-5.754, p = 0.007), 24 h intracerebral hemorrhage (ICH; OR = 4.029, 95%CI 1.844 ~ 8.803, p < 0.001) were independent risk factors for FR. The C-index of the nomogram of the derivation set and the verification set were 0.739 (95%CI 0.662~0.816) and 0.703 (95%CI 0.621~0.785), respectively. Conclusion: The nomogram composed of age, SBP, OTR, and 24 h ICH can effectively predict the probability of FR after MT in AIS patients.

Long term for patients with futile endovascular reperfusion after stroke.

AIMS: With the progress of thrombectomy technology, the vascular recanalization rate of patients with stroke has been continuously improved, but the proportion of futile recanalization (FR) is still quite a few. The long-term prognosis and survival of patients with FR and its influencing factors remain unclear. METHODS: Consecutive patients who received endovascular treatment (EVT) for ischemic stroke were enrolled between 2013 and 2021 from a single-center prospectively registry study. We evaluated the long-term outcome of these patients by Kaplan-Meier survival analysis, and the multivariable logistic regression curve was performed to analyze influencing factors. RESULTS: Among 458 patients with FR, 56.4% of patients survived at 1 year, and 50.4% at 2 years. In the multivariate regression analysis, age, premorbid modified Rankin Scale (mRS), National Institutes of Health Stroke Scale (NIHSS), posterior circulation infarct, general anesthesia, symptomatic intracerebral hemorrhage (sICH), and decompressive craniectomy were found to be related to unfavorable outcomes in long-term. Age, premorbid mRS, NIHSS, general anesthesia, and sICH were predictors of long-term mortality. CONCLUSIONS: Futile recanalization accounts for a large proportion of stroke patients after thrombectomy. This study on the long-term prognosis of such patients is beneficial to the formulation of treatment plans and the prediction of therapeutic effects.

Systemic Immune-Inflammation Response is Associated with Futile Recanalization After Endovascular Treatment.

BACKGROUND: Frequent incidence of futile recanalization decreases the benefit of endovascular treatment (EVT) in acute ischemic stroke. We hypothesized that the inflammation and immune response after ischemic are associated with futile recanalization. We aimed to investigate the correlation of admission systemic immune-inflammation index (SII) with futile recanalization post EVT. METHODS: Patients with successful recanalization (modified Thrombolysis in Cerebral Ischemia angiographic score 2b-3) and maintained artery recanalized after 24 h of EVT were chosen from a prospective nationwide registry study. Futile recanalization was defined as a poor functional outcome (modified Rankin Scale score 3-6) at 90 days, irrespective of a successful recanalization. At admission, SII was calculated as (platelet count × neutrophil count)/lymphocyte count/100. Logistic regression analysis helped to test the relationship of SII with futile recanalization. RESULTS: Among the 1,002 patients included, futile recanalization occurred in 508 (50.70%). No matter whether tested as quartiles or continuous variables, SII was significantly associated with futile recanalization (P < 0.05), and for every one standard deviation increase of SII, the risk of futile recanalization elevated by 22.3% (odds ratio 1.223, 95% confidence interval 1.053-1.444, P = 0.0093). Moreover, no significant interactions could be observed between SII or SII quartiles and age, baseline National Institutes of Health Stroke Scale scores, onset-to-recanalization time, and modified Thrombolysis in Cerebral Ischemia angiographic scores (all P for interaction > 0.05). CONCLUSIONS: Early SII elevation was associated with an increased risk of futile recanalization among patients with EVT. Our results indicated that therapeutic drug targeting hyperreactive immune-inflammation response might be helpful for reducing the incidence of futile recanalization.

Systemic biomarker associated with poor outcome after futile reperfusion.

BACKGROUND: Successful recanalization does not lead to complete tissue reperfusion in a considerable percentage of ischemic stroke patients. This study aimed to identify biomarkers associated with futile recanalization. Leukoaraiosis predicts poor outcomes of this phenomenon. Soluble tumour necrosis factor-like weak inducer of apoptosis (sTWEAK), which is associated with leukoaraiosis degrees, could be a potential biomarker. METHODS: This study includes two cohorts of ischemic stroke patients in a multicentre retrospective observational study. Effective reperfusion, defined as a reduction of ≥8 points in the National Institutes of Health Stroke Scale (NIHSS) within the first 24 h, was used as a clinical marker of effective reperfusion. RESULTS: In the first cohort study, female sex, age, and high NIHSS at admission (44.7% vs. 81.1%, 71.3 ± 13.7 vs. 81.1 ± 6.7; 16 [13, 21] vs. 23 [17, 28] respectively; p < .0001) were confirmed as predictors of futile recanalization. ROC curve analysis showed that leukocyte levels (sensitivity of 99%, specificity of 55%) and sTWEAK level (sensitivity of 92%, specificity of 88%) can discriminate between poor and good outcomes. Both biomarkers simultaneously are higher associated with outcome after effective reperfusion (OR: 2.17; CI 95% 1.63-4.19; p < .0001) than individually (leukocytes OR: 1.38; CI 95% 1.00-1.64, p = .042; sTWEAK OR: 1.00; C I95% 1.00-1.01, p = .019). These results were validated using a second cohort, where leukocytes and sTWEAK showed a sensitivity of 100% and specificity of 66.7% and 75% respectively. CONCLUSIONS: Leukocyte and sTWEAK could be biomarkers of reperfusion failure and subsequent poor outcomes. Further studies will be necessary to explore its role in reperfusion processes.

Predictive role of neutrophil-to-platelet ratio in futile recanalization of patients after endovascular therapy.

Aim: To explore the association between the neutrophil-to-platelet ratio (NPR) and futile recanalization (FR) in patients with acute ischemic stroke due to large vascular occlusions after endovascular therapy (EVT). Methods: FR after EVT was defined as a poor 90-day prognosis (modified Rankin scale [mRS] score ≥3) despite successful reperfusion (modified thrombolysis in cerebral infarction grade 2b-3). Patients were divided into high NPR (>35; n = 115) and low NPR (≤35; n = 81) groups. Results: The FR rate was significantly higher in the high NPR group than low NPR group (81.74 vs 55.56%; p = 0.000). NPR was independently associated with FR (odds ratio: 2.107; 95% CI: 1.017-4.364; p = 0.045). Conclusion: High NPR was associated with the risk of FR in patients with acute ischemic stroke due to large vascular occlusions.

Predicting Futile Recanalization in Acute Ischemic Stroke Patients Undergoing Endovascular Thrombectomy: The Role of White Blood Cell Count to Mean Platelet Volume Ratio.

BACKGROUND: Approximately half of AIS patients have an unfavorable outcome even after complete reperfusion. White blood cell (WBC) count to mean platelet volume (MPV) ratio (WMR) may be a promising predictive factor for futile recanalization. This study aimed to determine the predictive value of WMR in identifying individuals at higher risk of futile recanalization. METHODS: In this retrospective cohort study, 296 patients who achieved complete reperfusion after endovascular treatment (EVT) were included in the analysis. WBC count and MPV were collected at admission. Multivariable logistic regression was used to examine the independent association of the WMR with functional outcomes at three months. Net reclassification improvement (NRI) and integrated discrimination improvement (IDI) analyses were used to compare the accuracy of WMR for predicting futile recanalization. RESULTS: The adjusted odds ratios for the fourth quartile of WMR were 3.142 (95% CI 1.405- 7.027, P = 0.005) for unfavorable outcomes at 3 months in comparison with the first quartile. The inclusion of WMR in the traditional model enabled a more accurate prediction of unfavorable outcomes (NRI 0.250, P = 0.031; IDI 0.022, P = 0.017). CONCLUSION: Elevated WMR at admission was independently associated with futile recanalization among AIS patients who received EVT and might be useful in identifying futile recanalization.

Lymphocyte to Monocyte Ratio is Independently Associated with Futile Recanalization in Acute Ischemic Stroke After Endovascular Therapy.

Background and Purpose: Acute ischemic stroke (AIS) caused by large artery occlusion (LAO) poses considerable risks in terms of mortality and disability. Endovascular treatment (EVT) has emerged as a primary intervention for this condition. However, the occurrence of futile recanalization (FR) following EVT remains common, necessitating the identification of predictive markers for treatment outcomes. Although the lymphocyte to monocyte ratio (LMR) has been linked to various diseases, its association with FR after EVT in AIS patients has not been investigated. Methods: An analysis was conducted on patients with AIS who underwent EVT within 24 hours of symptom onset. The success of reperfusion was evaluated using the modified Thrombolysis in Cerebral Infarction (mTICI) scale, with patients achieving an mTICI score of ≥2b being included in the study. Various clinical, radiological, and laboratory variables, including lymphocyte-to-monocyte ratio (LMR), neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR), were collected. Logistic regression analysis was used to determine factors associated with FR, and receiver operating characteristic (ROC) analysis was performed to assess the predictive value of LMR. Results: Among the cohort of 101 patients, it was observed that 52.4% experienced FR. Upon admission, lower levels of lymphocyte-to-monocyte ratio (LMR) were found to be associated with older age, higher baseline NIHSS scores, lower ASPECTS, and poorer mRS scores at 90 days. Both univariate and multivariate logistic regression analyses indicated that low LMR independently predicted FR, with an adjusted odds ratio of 0.64 (95% CI = 0.412-0.984, p = 0.042). ROC analysis further demonstrated that LMR had an area under the curve (AUC) of 0.789 for predicting FR. Conclusion: This study establishes the potential value of the lymphocyte-to-monocyte ratio (LMR) as a prognostic marker for predicting FR in patients with AIS undergoing EVT. Decreased LMR levels are associated with unfavorable clinical outcomes.

Predictors of futile recanalization after endovascular treatment in acute ischemic stroke: a multi-center study.

Background and objectives: Endovascular thrombectomy (EVT) improves long-term outcomes and decreases mortality in ischemic stroke patients. However, a significant proportion of patients do not benefit from EVT recanalization, a phenomenon known as futile recanalization or reperfusion without functional independence (RFI). In this study, we aim to identify the major stroke risk factors and patient characteristics associated with RFI. Methods: This is a retrospective cohort study of 297 consecutive patients with ischemic stroke who received EVT at three academic stroke centers in China from March 2019 to March 2022. Patient age, sex, modified Rankin Scale (mRS), National Institute of Health Stroke Scale (NIHSS), Alberta stroke program early CT score (ASPECTS), time to treatment, risk factors and comorbidities associated with cerebrovascular diseases were collected, and potential associations with futile recanalization were assessed. RFI was successful reperfusion defined as modified thrombolysis in cerebral infarction (mTICI) ≥ 2b without functional independence at 90 days (mRS ≥ 3). Results: Of the 297 initial patients assessed, 231 were included in the final analyses after the application of the inclusion and exclusion criteria. Patients were divided by those who had RFI (n = 124) versus no RFI (n = 107). Older age (OR 1.041, 95% CI 1.004 to 1.073; p = 0.010), chronic kidney disease (OR 4.399, 0.904-21.412; p = 0.067), and higher 24-h NIHSS (OR 1.284, 1.201-1.373; p < 0.001) were independent predictors of RFI. Conversely, an mTICI score of 3 was associated with a reduced likelihood of RFI (OR 0.402, 0.178-0.909; p = 0.029). Conclusion: In conclusion, increased age, higher 24-h NIHSS and lack of an mTICI score of 3 were independently associated with RFI and have potential prognostic values in predicting patients that are less likely to respond to EVT recanalization therapy.

Postoperative blood glucose increase is associated with futile recanalization in patients with successful thrombectomy: a retrospective study.

BACKGROUND: Timely recognition of futile recanalization might enable a prompt response and an improved outcome in post-thrombectomy patients. This study aims to evaluate whether postoperative blood glucose increase (BGI) could act as an indicator of futile recanalization in patients receiving a successful thrombectomy. METHODS: This is a single-center, retrospective analysis of patients with anterior circulation large-vessel occlusion and successful thrombectomy between February 2019 and June 2022. BGI was defined as a higher level of blood glucose at the first postoperative morning than at admission. Futile recanalization was defined as patients with a modified Rankin Scale score of 3-6 at 90 days after onset. Multivariable binary logistic regression was used to assess the association of BGI with futile recanalization. RESULTS: A total of 276 patients were enrolled, amongst which 120 patients (43.5%) had BGI. Futile recanalization was more prevalent among patients with BGI compared to those without (70.0 vs. 49.4%, P = 0.001). After adjusting for potential confounders, BGI was associated with a higher likelihood of futile recanalization (adjusted OR: 2.97, 95%CI: 1.50-5.86, P = 0.002). This association was consistently observed regardless of diabetes history, occlusion site, time from symptom onset to groin puncture, or reperfusion status. CONCLUSION: Our findings support BGI serving as an indicator of futile recanalization in patients with anterior circulation large-vessel occlusion and successful thrombectomy.

Postoperative fibrinogen-to-albumin ratio acting as an indicator of futile recanalization in patients with successful thrombectomy.

BACKGROUND: Timely recognition of futile recanalization might enable a prompter response and thus improve outcomes in patients receiving successful thrombectomy. This study aims to evaluate whether postoperative fibrinogen-to-albumin ratio (FAR) could act as an indicator of futile recanalization. METHODS: This is a single-center, retrospective analysis of patients with acute anterior circulation large-vessel occlusion and successful thrombectomy between May 2019 and June 2022. FAR was defined as postoperative blood levels of fibrinogen divided by those of albumin, and dichotomized into high and low levels based on the Youden index. Futile recanalization was defined as patients achieving a successful recanalization with a modified Rankin Scale score of 3-6 at 90 days. Multivariable logistic regression was used to assess the association of FAR with futile recanalization. RESULTS: A total of 255 patients were enrolled, amongst which 87 patients (34.1%) had high postoperative FAR. Futile recanalization was more prevalent among patients with high FAR compared to those with low FAR (74.7% vs. 53.0%, p = .001). After adjusting for potential confounders, high postoperative FAR was found to independently correspond with the occurrence of futile recanalization (adjusted OR 2.40, 95%CI 1.18-4.87, p = .015). This association was consistently observed regardless of prior antithrombotic therapy, treatment of intravenous thrombolysis, occlusion site, time from symptom onset to groin puncture, and reperfusion status. CONCLUSION: Our findings support high postoperative FAR serving as an indicator of futile recanalization in patients with anterior circulation large-vessel occlusion and successful thrombectomy.

Proteomic analysis of jugular venous blood in acute large vessel occlusion stroke with futile recanalization.

Futile recanalization (FR) after endovascular treatment (EVT) remains a significant challenge for acute ischemic stroke (AIS) with large vessel occlusion (LVO). The pathogenesis of FR has not been well elucidated. We prospectively enrolled anterior circulation LVO-AIS patients who achieved successful recanalization after EVT. The jugular venous blood ipsilateral to stroke was collected before and immediately after recanalization. Plasma proteomic analysis based on liquid chromatography-mass spectrometry was performed using data-independent acquisition method. Differentially expressed proteins (DEPs) among patients with or without FR in the whole or propensity score matching (PSM) cohorts were screened according to the absolute value of fold change ≥1.5 and P value <0.05. We identified 104 and 34 DEPs between patients with or without FR in the whole cohort and PSM cohort, respectively. Bioinformatic analysis indicated that the identified proteins were primarily related to specific biological processes including immune response, complement activation, oxidative stress, lipid metabolism, protein ubiquitylation as well as autophagy, suggesting that these may be mechanisms in FR pathogenesis. Collectively, we discovered proteins that may be potential research targets for FR. The combination of proteomic and bioinformatic analysis could provide a better understanding of the pathogenesis of FR in a comprehensive manner.

Comprehensive Meta-Analysis of Futile Recanalization in Acute Ischemic Stroke Patients Undergoing Endovascular Thrombectomy: Prevalence, Factors, and Clinical Outcomes.

BACKGROUND: Futile recanalization (FR) continues to raise concern despite the success of endovascular thrombectomy (EVT) in acute ischemic stroke (AIS). Understanding the prevalence of FR and identifying associated factors are crucial for refining patient prognoses and optimizing management strategies. OBJECTIVES: This study aims to comprehensively assess the pooled prevalence of FR, explore the diverse factors connected with FR, and establish the association of FR with long-term clinical outcomes among AIS patients undergoing EVT. MATERIALS AND METHODS: Incorporating studies focusing on FR following EVT in AIS patients, we conducted a random-effect meta-analysis to assess the pooled prevalence and its association with various clinical and imaging risk factors linked to FR. Summary estimates were compiled and study heterogeneity was explored. RESULTS: Our comprehensive meta-analysis, involving 11,700 AIS patients undergoing EVT, revealed a significant pooled prevalence of FR at 51%, with a range of 48% to 54% (Effect Size [ES]: 51%; 95% Confidence Interval [CI]: 48-54%; z = 47.66; p < 0.001). Numerous clinical factors demonstrated robust correlations with FR, including atrial fibrillation (Odds Ratio [OR]: 1.39, 95% CI 1.22 1.59; p < 0.001), hypertension (OR 1.65, 95% CI 1.41 1.92; p < 0.001), diabetes mellitus (OR 1.71, 95% CI 1.47 1.99; p < 0.001), previous stroke or transient ischemic attack (OR 1.298, 95% CI 1.06 1.59; p = 0.012), prior anticoagulant usage (OR 1.33, 95% CI 1.08 1.63; p = 0.007), cardioembolic strokes (OR 1.34, 95% CI 1.10 1.63; p = 0.003), and general anesthesia (OR 1.53, 95% CI 1.35 1.74; p < 0.001). Conversely, FR exhibited reduced likelihoods of smoking (OR 0.66, 95% CI 0.57 0.77; p < 0.001), good collaterals (OR 0.33, 95% CI 0.23 0.49; p < 0.001), male sex (OR 0.87, 95% CI 0.77 0.97; p = 0.016), and intravenous thrombolysis (IVT) (OR 0.75, 95% CI 0.66 0.86; p < 0.001). FR was strongly associated with increasing age (standardized mean difference [SMD] 0.49, 95% CI 0.42 0.56; p < 0.0001), baseline systolic blood pressure (SMD 0.20, 95% CI 0.13 0.27; p < 0.001), baseline National Institute of Health Stroke Severity Score (SMD 0.75, 95% CI: 0.65 0.86; p < 0.001), onset-to-treatment time (SMD 0.217, 95% CI 0.13 0.30; p < 0.001), onset-to-recanalization time (SMD 0.38, 95% CI 0.19; 0.57; p < 0.001), and baseline blood glucose (SMD 0.31, 95% CI 0.22 0.41; p < 0.001), while displaying a negative association with reduced baseline Alberta Stroke Program Early CT Score (ASPECTS) (SMD -0.37, 95% CI -0.46 -0.27; p < 0.001). Regarding clinical outcomes, FR was significantly associated with increased odds of symptomatic intracranial hemorrhages (OR 7.37, 95% CI 4.89 11.12; p < 0.001), hemorrhagic transformations (OR 2.98, 95% CI 2.37 3.75; p < 0.001), and 90-day mortality (OR 19.24, 95% CI 1.57 235.18; p = 0.021). CONCLUSIONS: The substantial prevalence of FR, standing at approximately 51%, warrants clinical consideration. These findings underscore the complexity of FR in AIS patients and highlight the importance of tailoring management strategies based on individual risk factors and clinical profiles.

Parenchymal Blood Volume Changes Immediately After Endovascular Thrombectomy Predict Futile Recanalization in Patients with Emergent Large Vessel Occlusion.

OBJECTIVE: More than one third of acute ischemic stroke (AIS) patients do not recover to functional independence even if endovascular thrombectomy (EVT) is performed rapidly and successfully. This suggests that angiographic recanalization does not necessarily lead to tissue reperfusion. Although recognition of reperfusion status after EVT is pivotal for optimal postoperative management, reperfusion imaging assessment immediately after recanalization has not been fully investigated. The present study aimed to evaluate whether reperfusion status based on parenchymal blood volume (PBV) assessment after angiographic recanalization influences infarct growth and functional outcome in patients who have undergone EVT following AIS. METHODS: Seventy-nine patients who underwent successful EVT for AIS were retrospectively analyzed. PBV maps were acquired from flat-panel detector computed tomography (CT) perfusion images before and after angiographic recanalization. Reperfusion status was assessed from PBV values and their changes in regions of interest and collateral score. RESULTS: Post-EVT PBV ratio and ΔPBV ratio, as PBV parameters indicating the degree of reperfusion, were significantly lower in the unfavorable prognosis group (P < 0.01 each). Poor reperfusion on PBV mapping was associated with significantly longer puncture-to-recanalization time, lower collateral score, and higher frequency of infarct growth. Logistic regression analysis identified low collateral score and low ΔPBV ratio as associated with poor prognosis after EVT (odds ratios, 2.48, 3.72; 95% confidence intervals, 1.06-5.81, 1.20-11.53; P = 0.04, 0.02, respectively). CONCLUSIONS: Poor reperfusion in severely hypoperfused territories on PBV mapping immediately after recanalization may predict infarct growth and unfavorable prognosis in patients who undergo EVT following AIS.

No-reflow phenomenon in acute ischemic stroke: an angiographic evaluation.

BACKGROUND: Futile recanalization (FR) is de fined as a poor 90-day outcome or lack of neurological improvement at 24 h despite successful recanalization in acute ischemic stroke (AIS) with large vessel occlusion (LVO) treated by mechanical throbectomy (MT). The No-reflow phenomenon (NRP) could be a possible cause of FR, but its evidence in AIS patients is scarce. METHODS: We retrospectively analyzed 185 digital subtraction angiographies (DSA) of AIS patients with anterior circulation LVO after endovascular treatment. To better define NRP, we designed a score called the modified capillary index score (mCIS). The score is obtained by dividing the middle cerebral artery territory in three segments. For each segment, we gave 2 points if the capillary blush was present without any delay, 1 if delayed, and 0 if absent. The primary endpoint was to use mCIS to identify NRP on post-interventional DSA and to test whether this marker may predict FR and failure of early neurological improvement (fENI). The secondary endpoint was to search for a correlation between NRP, lesion volume, and hemorrhagic transformation. We used the ROC curve to define mCIS ≤ 3 as the cut-off and marker of NRP. RESULTS: NRP was present in 35.1% of patients. NRP predicted fENI at 24 h (aOR 2.825, 95% CI 1.265-6.308, P = 0.011) and at 7 days (aOR 2.191, 95% CI 1.008-4.762, P = 0.048), but not 90-day FR. Moreover, NRP predicted hemorrhagic transformation (aOR 2.444, 95% CI 1.266-4.717, P = 0.008). CONCLUSIONS: The modified capillary index score (mCIS) seems useful in identifying NRP in AIS. In addition, mCIS was able to predict NRP that correlated with early clinical outcome and hemorrhagic transformation of the ischemic lesion. An external validation of the score is warranted.

Stress hyperglycemia as a modifiable predictor of futile recanalization in patients undergoing mechanical thrombectomy for acute ischemic stroke.

Introduction: Mechanical thrombectomy (MT) is the first line treatment in acute ischemic stroke (AIS) due to large vessel occlusion (LVO). Approximately half of patients treated with MT does not have a favorable outcome 3 months after stroke. The aim of this study was to identify predictors of futile recanalization (FR) in patients with LVO treated with MT. Methods: A retrospective analysis of consecutive patients with acute ischemic stroke due to anterior circulation LVO who underwent MT. Patients with a TICI score of 2b or 3 were included. We distinguished two groups, FR and meaningful recanalization (MR), according to patients' disability three months after stroke (FR: mRS score > 2; MR: mRS score < 2). Results: We enrolled 238 patients (FR, n = 129, 54.2%; MR, n = 109, 45.8%). Age (OR 1.05, 95% CI 1.01-1.09, p = 0.012), female sex (OR 2.43, 95% CI 1.12-5.30, p = 0.025), stress hyperglycemia, as measured by the GAR index, (OR 1.17, 95% CI 1.06-1.29, p = 0.002), NIHSS at admission (OR 1.15, 95% CI 1.07-1.25, p = 0.001) and time from symptoms onset to MT (OR 1.01, 95% CI 1.00-1.01, p = 0.020) were independent predictors of FR. The AUC for the model combining age, female sex, GAR index, NIHSS at admission and time from symptoms onset to MT was 0.81 (95% CI 0.76-0.87; p < 0.001). The optimal GAR index cut-off score to predict FR was 17.9. Discussion: FR is common after MT. We recognized older age, female sex and baseline NIHSS as non-modifiable predictors of FR. On the other hand, time from symptoms onset to MT and stress hyperglycemia were modifiable pre- and post-MT factors, respectively. Any effort should be encouraged to reduce the impact of these modifiable predictors.