Predictors of intracranial hemorrhage in acute ischemic stroke after endovascular thrombectomy

Evaluation of pure subarachnoid hemorrhage after mechanical thrombectomy in a series of 781 consecutive patients

IntroductionSubarachnoid hyperdensity is commonly seen on postoperative computed tomography scans within 24 h after mechanical thrombectomy. The impact on patients' outcomes remains uncertain. We present a real-world experience evaluating periprocedural factors associated with the development of subarachnoid hemorrhage (SAH) and its impact on outcomes of patients with acute stroke undergoing mechanical thrombectomy.MethodsA single-center, retrospective analysis was performed between January 2016 and August 2021, including all consecutive patients who underwent thrombectomy. Our study aimed to evaluate periprocedural factors associated with subarachnoid hemorrhage within 24 h of the intervention, and the potential impact on patients' outcome.ResultsOf 781 patients, 44 patients (5.63%) demonstrated pure SAH within 24 h of the intervention. Patients from the SAH group were more likely to have tandem occlusion (15.9% vs. 5.2%, p = .003), aspiration using reperfusion pump system (81.4% vs. 66.8%, p = .047), intraoperative complications (9.1% vs. 0.9%; p < .001), longer puncture-to-recanalization times (45 min vs 29 min, p = .042) and a higher median number of passes to achieve recanalization (1 vs. 3, p = .002). There was no statistically significant difference in the long-term functional outcome between the groups.ConclusionWe suggest that dual-energy computed tomography could better distinguish between blood and pure contrast stagnation. Still, SAH was not associated with an unfavorable outcome in stroke patients undergoing thrombectomy.

Subarachnoid iodine leakage on dual-energy computed tomography after mechanical thrombectomy is associated with malignant brain edema

BACKGROUND

Dual-energy computed tomography (DE-CT) can differentiate between hemorrhage and iodine contrast medium leakage following mechanical thrombectomy (MT) for acute ischemic stroke (AIS). We determined whether subarachnoid hemorrhage (SAH) and subarachnoid iodine leakage (SAIL) on DE-CT following MT were associated with malignant brain edema (MBE).

METHODS

We analyzed the medical records of 81 consecutive anterior circulation AIS patients who underwent MT. SAH or SAIL was diagnosed via DE-CT performed immediately after MT. We compared the procedural data, infarct volumes, MBE, and modified Rankin scale 0-2 at 90 days between patients with and without SAH and between patients with and without SAIL. Furthermore, we evaluated the association between patient characteristics and MBE.

RESULTS

A total of 20 (25%) patients had SAH and 51 (63%) had SAIL. No difference in diffusion-weighted imaging (DWI)-infarct volume before MT was observed between patients with and without SAH or patients with and without SAIL. However, patients with SAIL had larger DWI-infarct volumes 1 day following MT than patients without SAIL (95 mL vs 29 mL; p=0.003). MBE occurred in 12 of 81 patients (15%); more patients with SAIL had MBE than patients without SAIL (22% vs 3%; p=0.027). Severe SAIL was significantly associated with MBE (OR, 12.5; 95% CI, 1.20-131; p=0.006), whereas SAH was not associated with MBE.

CONCLUSION

This study demonstrated that SAIL on DE-CT immediately after MT was associated with infarct volume expansion and MBE.

Prediction of Symptomatic Intracranial Hemorrhage Before Mechanical Thrombectomy Using Machine Learning in Patients with Anterior Circulation Large Vessel Occlusion

BACKGROUND

Symptomatic intracranial hemorrhage (sICH) after mechanical thrombectomy (MT) is associated with worse outcomes. We sought to develop and internally validate a machine learning (ML) model to predict sICH prior to MT in patients with anterior circulation large vessel occlusion.

METHODS

Consecutive adults who underwent MT for internal carotid artery/M1/M2 occlusions at a single institution were reviewed. The data was split into 80% training and 20% hold-out test sets. 9 ML models were screened. The top performing ML model was compared to logistic regression and previously described clinical prediction models. SHapley Additive exPlanations were used to identify the most predictive features in the ML model.

RESULTS

A total of 497 patients met inclusion criteria. The top performing ML model was extreme gradient boosting. The area under the receiver operating characteristics curve for the ML model on the test set was 0.79 (95% confidence interval [CI] 0.67-0.89), which was significantly higher (P < 0.001) than the logistic regression model (0.54 [95% CI 0.33-0.76]). The ML model also performed significantly better than the TAG = TICI-ASPECTS-glucose score (0.69 [95% CI 0.55-0.85], P < 0.001), Systolic blood pressure-Time-Blood glucose-ASPECTS score (0.45 [95% CI 0.30-0.60], P < 0.001), and ChatGPT 4.0 (0.60 [95% CI 0.48-0.68], P < 0.001). Based on SHapley Additive exPlanations values the most predictive features of sICH in the ML model were lower Alberta Stroke Program Early CT score, lower collateral score, and higher presenting National Institutes of Health Stroke Scale.

CONCLUSIONS

An ML model accurately predicted sICH prior to MT. It performed better than a standard statistical model and previously described clinical prediction models.

Comparison of HEmorrhage on CT versus MRI After ThrombEctomy: The HECATE study

Background

The characterization of hemorrhage following acute stroke intervention has largely been CT-based. We sought to compare MRI- and CT-based scoring of hemorrhage after acute endovascular therapy (EVT) applying the Heidelberg Bleeding Classification (HBC) to assess inter-modal agreement and quantify inter-rater agreement.

Methods

Consecutive acute stroke patients were included in this retrospective study if they: i) had MRI and CT ≤12 hours of each other OR ii) had CT bracketed by MRI pre- and post-CT [i.e. MRI-CT-MRI] ≤7 days post-EVT. The concordance of the HBC ratings by consensus panel were compared between CT and T2*GRE MRI.

Results

For the 87 EVT-treated patients included, median age was 68 years [60-74], admit NIHSS 18 [13-23], 47% were treated with IV/IA thrombolytics, and 93% were successfully recanalized (mTICI 2b/3). Hemorrhage was detected on at least one modality in 60% (52/87) of patients. We found a 68% (59/87, 95% CI [57-77%]) agreement overall between CT and MRI for hemorrhage classification post-EVT. MRI had the best inter-rater agreement for HBC 0 (no hemorrhage) with excellent concordance (κ=0.882), compared to CT (κ=0.683). T2*GRE MRI tended to have increased sensitivity to scattered petechial hemorrhage (HBC 1a) as compared to CT with 17% (2/12) inter-modal agreement. The inter-rater agreement of HBC class 2 (i.e. PH-2) was substantial for MRI (κ=0.781) and excellent in CT (κ=0.951), with 67% (8 /12) inter-modal agreement. SAH was detected in 24% (21/87) of patients on CT and/or MRI with 29% (6/21) inter-modal agreement.

Conclusions

With the exception of SAH and minor petechial hemorrhagic transformation, we found that MRI and CT are overall interchangeable for detecting and classifying hemorrhage after endovascular therapy, reassuring findings for both clinical-decision making and research application. Given the complexity of hemorrhage subtypes post-EVT, work to further refine a post-EVT hemorrhage classification scale with clinical correlation would be beneficial.

Ten-year trends, disparities, and clinical impact of stroke thrombectomy and thrombolysis: A single center experience 2012-2021

OBJECTIVES

As indications for acute ischemic stroke treatment expand, it is unclear whether disparities in treatment utilization and outcome still exist. The main objective of this study was to investigate disparities in acute ischemic stroke treatment and determine impact on outcome.

MATERIALS AND METHODS

Retrospective observational cohort study of consecutive ischemic stroke admissions to a comprehensive stroke center from 2012-2021 was performed. Primary exposure was intravenous thrombolysis and/or endovascular thrombectomy. Primary end points were discharge modified Rankin Scale, home disposition, and expired/hospice. Multivariable logistic regression analyses were conducted to elucidate disparities in treatment utilization and determine impact on outcome.

RESULTS

Of 517,615 inpatient visits, there were 7,540 (1.46 %) ischemic stroke admissions, increasing from 1.14 % to 1.79 % from 2012-2021. Intravenous thrombolysis significantly decreased from 14.4 % to 9.8 % while endovascular thrombectomy significantly increased from 0.8 % to 10.5 %. Both intravenous thrombolysis and endovascular thrombectomy increased odds of discharge home and modified Rankin Scale 0-2, and thrombectomy decreased odds of expired/hospice. After adjusting for covariates, decreased odds of thrombectomy was associated with Medicaid insurance (Odds Ratio [95 % Confidence Interval] 0.55 [0.32-0.93]), age 80+ (0.49 [0.35-0.69]), prior stroke (0.49 [0.31-0.77]), and diabetes mellitus (0.55 [0.39-0.79]), while low median household income (<$80,000/year) increased odds of no acute treatment (1.34 [1.16-1.56]). No sex or racial disparities were observed. Medicaid and low-income were not associated with worse clinical outcomes.

CONCLUSIONS

Less endovascular thrombectomy occurred in Medicaid, older, prior stroke, and diabetic patients, while low-income was associated with no treatment. The observed socioeconomic disparities did not impact discharge outcome.

A clinical and computed tomography-based nomogram to predict the outcome in patients with anterior circulation large vessel occlusion after endovascular mechanical thrombectomy

PURPOSE

To explore the positive predictors of the clinical outcome in acute ischemic stroke (AIS) patients with anterior circulation large vessel occlusion (ACLVO) after endovascular mechanical thrombectomy (EMT) at a 90-day follow-up, and to establish a nomogram model to predict the clinical outcome.

MATERIALS AND METHODS

AIS patients with ACLVO detected by multimodal Computed Tomography imaging who underwent EMT were collected. Patients were divided into the favorable and the unfavorable groups according to the 90-day modified Rankin Scale (mRS) score. Univariate and multivariate analyses were performed to investigate predictors of the favorable outcome (mRS of 0-2). A nomogram model for predicting the clinical outcome after EMT was drawn, and the receiver operating characteristic (ROC) curve was used to evaluate its predictive value.

RESULTS

Totally 105 patients including 65 patients in the favorable group and 40 in the unfavorable group were enrolled. Multivariate logistic regression analysis showed that admission National Institute of Health Stroke scale (NIHSS) score [0.858 (95% CI 0.778-0.947)], ACLVO at M2 [20.023 (95% CI 2.204-181.907)] and infarct core (IC) volume [0.943 (95% CI 0.917-0.969)] was positively correlated with favorable outcome. The accuracy of the nomogram model in predicting the outcome was 0.923 (95% CI 0.870-0.976), with a cutoff value of 119.6 points. The area under the ROC curve was 0.848 (95% CI 0.780-0.917; sensitivity, 79.7%; specificity, 90.0%).

CONCLUSION

A low Admission NIHSS score, ACLVO at M2, and a small IC volume were positive predictors for favorable outcome. The nomogram model may well predict the outcome in AIS patients with ACLVO after EMT.

Predictors of acute post-thrombectomy intracranial hemorrhage expansion in anterior circulation infarcts

BACKGROUND

Post-mechanical thrombectomy (MT) intracranial hemorrhage (ICH) is a major source of morbidity in treated acute ischemic stroke patients with large vessel occlusion. ICH expansion may further contribute to morbidity. We sought to identify factors associated with ICH expansion on imaging evaluation post-MT.

METHODS

We performed a retrospective cohort study of patients undergoing MT at a single comprehensive stroke center. Per protocol, patients underwent dual-energy head CT (DEHCT) post-MT followed by a 24-h interval non-contrast enhanced MRI. ICH expansion was defined as any increase in blood volume between the two studies if identified on the DEHCT. Univariate and multivariable analyses were performed to identify risk factors for ICH expansion.

RESULTS

ICH was identified on DEHCT in 13% of patients (n = 35/262), with 20% (7/35) demonstrating expansion on interval MRI. The average increase in blood volume was 11.4 ml (SD 6.9). Univariate analysis identified anticoagulant usage (57% vs 14%, p = 0.03), petechial hemorrhage inside the infarct margins or intraparenchymal hematoma on DEHCT (ECASS-II HI2/PH1/PH2) (71% vs 14%, p < 0.01), basal ganglia hemorrhage (71% vs 21%, p = 0.02), and basal ganglia infarction (86% vs 32%, p = 0.03) as factors associated with ICH expansion. Multivariate regression demonstrated that anticoagulant usage (OR 20.3, 95% C.I. 2.43-446, p < 0.05) and ECASS II scores of HI2/PH1/PH2 (OR 11.7, 95% C.I. 1.24-264, p < 0.05) were significantly predictive of ICH expansion.

CONCLUSION

Expansion of post-MT ICH on 24-h interval MRI relative to immediate post-thrombectomy DEHCT is significantly associated with baseline anticoagulant usage and petechial hemorrhage inside the infarct margins or presence of intraparenchymal hematoma (ECASS-II HI2/PH1/PH2).

First-pass effect in posterior acute ischemic stroke undergoing endovascular thrombectomy: A systematic review and meta-analysis

OBJECTIVES

First-pass effect (FPE) has been shown to be a predictor of favorable clinical outcomes following endovascular thrombectomy (EVT) for acute ischemic stroke (AIS) in the anterior circulation. Literature regarding FPE for posterior circulation AIS is sparse; we conducted a systematic review and meta-analysis to explore FPE in posterior circulation stroke undergoing EVT.

MATERIALS AND METHODS

We conducted a systematic review of the English literature in PubMed, Embase, Scopus, and Web of Science. FPE was defined as thrombolysis in cerebral infarction (TICI) 2c-3 and modified FPE (mFPE) was defined as TICI 2b-3 in one pass. Definitions of non-FPE and non-mFPE varied among studies. The primary outcome of interest was modified Rankin Scale (mRS) 0-2. Secondary outcomes of interest were mRS 0-3, symptomatic intracranial hemorrhage (sICH), and mortality. We calculated odds ratios (OR) and corresponding 95% confidence intervals (CI). Heterogeneity was assessed with Q statistic and I2 test.

RESULTS

Seven studies with 417 patients in the mFPE group, 942 in the non-mFPE group, 545 in the FPE group, and 1023 in the non-FPE group were included. Overall, FPE was associated with greater rates of 90-day mRS 0-2 (OR= 2.78, 95% CI= 2.11-3.65; P-value< 0.001) and mRS 0-3 (OR= 2.67, 95% CI= 1.98-3.60; P-value< 0.001); however, there was significant heterogeneity among studies for both mRS 0-2 (I2= 69%; P-value< 0.001) and mRS 0-3 (I2= 69%; P-value< 0.001). FPE and non-FPE were associated with similar rates of sICH (OR= 0.65, 95% CI= 0.40-1.07; P-value= 0.09), and no heterogeneity was observed (I2= 0%; P-value= 0.95). FPE was associated with lower rates of mortality (OR= 0.44, 95% CI= 0.33-0.58; P-value< 0.001), although heterogeneity was observed (I2= 58%; P-value= 0.01).

CONCLUSIONS

FPE is associated with favorable clinical outcomes in patients undergoing EVT for posterior circulation AIS. Future studies should work to further quantify the impact of FPE on outcomes in the posterior circulation.

The clinical utility of dual-energy CT in post-thrombectomy care: Part 1, predictors and outcomes of subarachnoid and intraparenchymal hemorrhage

OBJECTIVES

Dual-energy CT allows differentiation between blood and iodinated contrast. We aimed to determine predictors of subarachnoid and intraparenchymal hemorrhage on dual-energy CT performed immediately post-thrombectomy and the impact of these hemorrhages on 90-day outcomes.

MATERIALS AND METHODS

A retrospective analysis was performed on patients who underwent thrombectomy for anterior circulation large-vessel occlusion and subsequent dual-energy CT at a comprehensive stroke center from 2018-2021. The presence of contrast, subarachnoid hemorrhage, or intraparenchymal hemorrhage immediately post-thrombectomy was assessed by dual-energy CT. Univariable and multivariable analyses were performed to identify predictors of post-thrombectomy hemorrhages and 90-day outcomes. Patients with unknown 90-day mRS were excluded.

RESULTS

Of 196 patients, subarachnoid hemorrhage was seen in 17, and intraparenchymal hemorrhage in 23 on dual-energy CT performed immediately post-thrombectomy. On multivariable analysis, subarachnoid hemorrhage was predicted by stent retriever use in the M2 segment of MCA (OR,4.64;p=0.017;95%CI,1.49-14.35) and the number of thrombectomy passes (OR,1.79;p=0.019;95%CI,1.09-2.94;per an additional pass), while intraparenchymal hemorrhage was predicted by preprocedural non-contrast CT-based ASPECTS (OR,8.66;p=0.049;95%CI,0.92-81.55;per 1 score decrease) and preprocedural systolic blood pressure (OR,5.10;p=0.037;95%CI,1.04-24.93;per 10 mmHg increase). After adjusting for potential confounders, intraparenchymal hemorrhage was associated with worse functional outcomes (OR,0.25;p=0.021;95%CI,0.07-0.82) and mortality (OR,4.30;p=0.023,95%CI,1.20-15.36), while subarachnoid hemorrhage was associated with neither.

CONCLUSIONS

Intraparenchymal hemorrhage immediately post-thrombectomy was associated with worse functional outcomes and mortality and can be predicted by low ASPECTS and elevated preprocedural systolic blood pressure. Future studies focusing on management strategies for patients presenting with low ASPECTS or elevated blood pressure to prevent post-thrombectomy intraparenchymal hemorrhage are warranted.

Prediction of hemorrhagic transformation via pre-treatment CT radiomics in acute ischemic stroke patients receiving endovascular therapy

OBJECTIVE

This study aimed to extract radiomics features (RFs) from pre-treatment CT scans in patients with acute ischemic stroke (AIS), and to establish a radiomics model to predict hemorrhagic transformation (HT) after endovascular therapy (EVT).

METHODS

A total of 105 patients who were diagnosed with AIS [with occlusion of the M1 segment of the middle cerebral artery (MCA) and/or internal carotid artery] and received EVT were enrolled. They were randomly divided into the development cohort (n = 73) and the validation cohort (n = 32). The clinicoradiological data of all patients, including pre-treatment cranial CT without contrast enhancement, CT perfusion, and CT angiography, were obtained. The MCA territory on pre-treatment CT images was segmented to extract RFs associated with HT after EVT. Then, a CT radiomics model based on the selected RFs was constructed to predict HT after EVT.

RESULTS

The sensitivity, specificity, and area under the curve of the CT radiomics model for predicting HT after EVT based on pre-treatment CT RFs was 0.806, 0.649, and 0.781 (95% confidence interval (CI): 0.675-0.886), respectively, in the development cohort. The sensitivity, specificity, and area under the curve in the validation cohort was 0.625, 0.875, and 0.797 (95% CI: 0.642-0.951), respectively.

CONCLUSION

CT radiomics analysis is a valuable tool for predicting HT in AIS patients receiving EVT. It may guide the selection of patients in practice and improve procedural safety and effectiveness.

ADVANCES IN KNOWLEDGE

Identification of the importance of pre-treatment CT radiomics in the prediction of HT in AIS patients after EVT.

Predictors of outcome after endovascular treatment for tandem occlusions: a single center retrospective analysis

BACKGROUND

The endovascular treatment procedure in tandem occlusions (TO) is complex compared to single occlusion (SO) and optimal management remains uncertain. The aim of this study was to identify clinical and procedural factors that may be associated to efficacy and safety in the management of TO and compare functional outcome in TO and SO stroke patients.

METHODS

This is a retrospective single center study of medium (MeVO) and large vessel occlusion (LVO) of the anterior circulation. Clinical, imaging, and interventional data were analyzed to identify predictive factors for symptomatic intracranial hemorrhage (sICH) and functional outcome after endovascular treatment (EVT) in TO. Functional outcome in TO and SO patients was compared.

RESULTS

Of 662 anterior circulation stroke patients with MeVO and LVO stroke, 90 (14%) had TO. Stenting was performed in 73 (81%) of TO patients. Stent thromboses occurred in 8 (11%) patients. Successful reperfusion with modified thrombolysis in cerebral infarction (mTICI) ≥ 2b was achieved in 82 (91%). SICH occurred in seven (8%). The strongest predictors for sICH were diabetes mellitus and number of stent retriever passes. Good functional clinical outcome (mRS ≤ 2) at 90-day follow up was similar in TO and SO patients (58% vs 59% respectively). General anesthesia (GA) was associated with good functional outcome whereas hemorrhage in the infarcted tissue, lower mTICI score and history of smoking were associated with poor outcome.

CONCLUSIONS

The risk of sICH was increased in patients with diabetes mellitus and those with extra stent-retriever attempts. Functional clinical outcomes in patients with TO were comparable to patients with SO.

Association of Cortical Superficial Siderosis with Post-Stroke Epilepsy

OBJECTIVE

To assess whether post-stroke epilepsy (PSE) is associated with neuroimaging findings of hemosiderin in a case-control study, and whether the addition of hemosiderin markers improves the risk stratification models of PSE.

METHODS

We performed a post-hoc analysis of the PROgnosis of POST-Stroke Epilepsy study enrolling PSE patients at National Cerebral and Cardiovascular Center, Osaka, Japan, from November 2014 to September 2019. PSE was diagnosed when one unprovoked seizure was experienced >7 days after the index stroke, as proposed by the International League Against Epilepsy. As controls, consecutive acute stroke patients with no history or absence of any late seizure or continuing antiseizure medications at least 3 months after stroke were retrospectively enrolled during the same study period. We examined cortical microbleeds and cortical superficial siderosis (cSS) using gradient-echo T2*-weighted images. A logistic regression model with ridge penalties was tuned using 10-fold cross-validation. We added the item of cSS to the existing models (SeLECT and CAVE) for predicting PSE and evaluated performance of new models.

RESULTS

The study included 180 patients with PSE (67 women; median age 74 years) and 1,183 controls (440 women; median age 74 years). The cSS frequency was higher in PSE than control groups (48.9% vs 5.7%, p < 0.0001). Compared with the existing models, the new models with cSS (SeLECT-S and CAVE-S) demonstrated significantly better predictive performance of PSE (net reclassification improvement 0.63 [p = 0.004] for SeLECT-S and 0.88 [p = 0.001] for CAVE-S at the testing data).

INTERPRETATION

Cortical superficial siderosis was associated with PSE, stratifying stroke survivors at high risk of PSE. ANN NEUROL 2023;93:357-370.

What You Always Wanted to Know about Endovascular Therapy in Acute Ischemic Stroke but Never Dared to Ask: A Comprehensive Review

In 2015, mechanical thrombectomy (MT) in combination with intravenous thrombolysis was demonstrated to be superior to best medical treatment alone in patients with anterior circulation stroke. This finding resulted in an unprecedented boost in endovascular stroke therapy, and MT became widely available. MT was initially approved for patients presenting with large vessel occlusion in the anterior circulation (intracranial internal carotid artery or proximal middle cerebral artery) within a 6-hour time window. Eventually, it was shown to be beneficial in a broader group of patients, including those without known symptom-onset, wake-up stroke, or patients with posterior circulation stroke. Technical developments and the implementation of novel thrombectomy devices further facilitated endovascular recanalization for acute ischemic stroke. However, some aspects remain controversial. Is MT suitable for medium or very distal vessel occlusions? Should emergency stenting be performed for symptomatic stenosis or recurrent occlusion? How should patients with large vessel occlusion without disabling symptoms be treated? Do certain patients benefit from MT without intravenous thrombolysis? In the era of personalized decision-making, some of these questions require an individualized approach based on comorbidities, imaging criteria, and the severity or duration of symptoms. Despite its successful development in the past decade, endovascular stroke therapy will remain a challenging and fascinating field in the years to come. This review aims to provide an overview of patient selection, and the indications for and execution of MT in patients with acute ischemic stroke.

Independent Significance of Visual Assessment of Perfusion CT Maps in Anterior Circulation Stroke Patients Treated with Mechanical Thrombectomy

BACKGROUND

In the absence of an automated software analysis, the role of computed tomography perfusion (CTP) in a real time clinical practice is not well established. We evaluated the clinical significance of a widely accessible and simple visual grading scale of CTP in the anterior circulation of acute ischemic stroke (AIS) patients treated with mechanical thrombectomy (MT).

METHODS

The single center consecutive CT investigations of AIS patients treated with MT in the anterior circulation have been evaluated retrospectively. ASPECT score and collateral circulation evaluation based on the Maas score were determined. Time to peak parametric maps, derived from CTP, were graded into four categories, from least to most favorable. The primary endpoint was functional outcome evaluated as modified Rankin Scale (mRS) ≤ 2 at 90 days after MT.

RESULTS

We included 318 patients in the analysis; 142 (45%) patients had mRS ≤ 2 after 90 days, mortality rate was 24%. Higher CTP and Maas score were significantly correlated with better clinical outcome (Pearson χ² 25.0 and 37.7, respectively; p < 0.01). Collateral circulation and CTP grades were strongly interrelated (Pearson χ² 78.6; p < 0.01). The CTP grade demonstrated statistically significant independent correlation with the clinical outcome irrespective of the collateral circulation grade, ASPECT score and age (OR 2.5; p = 0.011). The correlation was more pronounced in patients with normal collateral circulation (OR 3.27; p = 0.029).

CONCLUSION

We demonstrated that both visually graded CTP and collateral circulation grade strongly correlated with the clinical outcome of MT in the anterior circulation of AIS patients. Importantly, CTP correlated with the clinical outcome independent of the collateral circulation.

Safety and efficacy of endovascular thrombectomy in acute ischemic stroke treated with anticoagulants: a systematic review and meta-analysis

Background

Endovascular thrombectomy (EVT) is an effective therapy in acute ischemic stroke (AIS) with large vessel occlusion, especially for those who are unsuitable for intravenous thrombolysis. However, the safety and efficacy of EVT in AIS patients who receiving oral anticoagulants (OACs) is unclear, especially for the risk of symptomatic intracranial hemorrhage (sICH). 

Methods

Database of PubMed, Embase, and Cochrane Library were searched from Jan 1, 2000, through the final search date of Jun 2, 2021. Eligible studies for enrollment required outcomes reported for events of sICH, mortality, functional status, and successful reperfusion. Meta-analysis was conducted to compare the outcomes difference after EVT between AIS patients with or without OACs use. The primary safety outcome was sICH after EVT, and the primary efficacy outcome was functional status at 3 months. 

Results

One thousand nine hundred forty studies were screened for eligibility and 15 of them were included in the meta-analysis. Compared the OACs group to control arm, vitamin K antagonists (VKAs) was associated with higher risk of sICH (OR 1.49, 95% CI 1.10–2.02) and mortality (OR 1.67, 95% CI 1.35–2.06). Poor functional outcomes were noted both in the VKAs and direct oral anticoagulants (DOACs) groups (OR 0.62, 95% CI 0.54–0.71 and OR 0.61, 95% CI 0.53–0.71, respectively). No differences in successful reperfusion were observed.

Conclusions

Comparing with DOACs, VKAs use was associated with a higher risk of sICH and mortality after EVT. Patients who did not receive OACs exhibited more favorable outcomes. The successful reperfusion did not differ between groups. However, results for mortality and functional outcomes have to be interpreted with caution since they are based on non-randomized data and unadjusted proportions.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12959-022-00394-y.

Determinants of Symptomatic Intracranial Hemorrhage After Endovascular Stroke Treatment: A Retrospective Cohort Study

Symptomatic intracranial hemorrhage (sICH) is a serious complication after endovascular treatment for ischemic stroke. We aimed to identify determinants of its occurrence and location.

Predictors of Symptomatic Hemorrhage After Endovascular Treatment for Anterior Circulation Occlusions: Turkish Endovascular Stroke Registry

We evaluated the predictive factors of symptomatic intracranial hemorrhage (SICH) in endovascular treatment of stroke. We included 975 ischemic stroke patients with anterior circulation occlusion. Patients that had hemorrhage and an increase of ≥4 points in their National Institutes of Health Stroke Scale (NIHSS) after the treatment were considered as SICH. The mean age of patients was 65.2±13.1 years and 469 (48.1%) were women. The median NIHSS was 16 (13-18) and Alberta Stroke Program Early CT 9 (8-10). In 420 patients (43.1%), modified Rankin Scale was favorable (0-2) and mortality was observed in 234 (24%) patients at the end of the third month. Patients with high diastolic blood pressure (P<.05) had significantly higher SICH. SICH was significantly higher in those with high NIHSS scores (P<.001), high blood glucose (P<.001), and leukocyte count at admission (P<.05). Diabetes mellitus (DM) (OR 1.90; P<.001), NIHSS (OR 1.07; P<.05), adjuvant intra-arterial thrombolytic therapy (IA-rtPA) (OR, 1.60; P<.05), and puncture-recanalization time (OR 1.01; P<.05) were independent factors of SICH. Higher baseline NIHSS score, longer procedure time, multiple thrombectomy maneuvers, administration of IA-rtPA, and the history of DM are independent predictors of SICH in anterior circulation occlusion.

Inflammatory Biomarkers and Intracranial Hemorrhage after Endovascular Thrombectomy

BACKGROUND

Intracranial hemorrhage after endovascular thrombectomy is associated with poorer prognosis compared with those who do not develop the complication. Our study aims to determine predictors of post-EVT hemorrhage - more specifically, inflammatory biomarkers present in baseline serology.

METHODS

We performed a retrospective review of consecutive patients treated with EVT for acute large vessel ischemic stroke. The primary outcome of the study is the presence of ICH on the post-EVT scan. We used four definitions: the SITS-MOST criteria, the NINDS criteria, asymptomatic hemorrhage, and overall hemorrhage. We identified nonredundant predictors of outcome using backward elimination based on Akaike Information Criteria. We then assessed prediction accuracy using area under the receiver operating curve. Then we implemented variable importance ranking from logistic regression models using the drop in Naegelkerke R2 with the exclusion of each predictor.

RESULTS

Our study demonstrates a 6.3% SITS (16/252) and 10.0% NINDS (25/252) sICH rate, as well as a 19.4% asymptomatic (49/252) and 29.4% (74/252) overall hemorrhage rate. Serologic markers that demonstrated association with post-EVT hemorrhage were: low lymphocyte count (SITS), high neutrophil count (NINDS, overall hemorrhage), low platelet to lymphocyte ratio (NINDS), and low total WBC (NINDS, asymptomatic hemorrhage).

CONCLUSION

Higher neutrophil counts, low WBC counts, low lymphocyte counts, and low platelet to lymphoycyte ratio were baseline serology biomarkers that were associated with post-EVT hemorrhage. Our findings, particularly the association of diabetes mellitus and high neutrophil, support experimental data on the role of thromboinflammation in hemorrhagic transformation of large vessel occlusions.

Subarachnoid Hemorrhage in Mechanical Thrombectomy for Acute Ischemic Stroke: Analysis of the STRATIS Registry, Systematic Review, and Meta-Analysis

Background: The indications for mechanical thrombectomy in acute ischemic stroke continue to broaden, leading neurointerventionalists to treat vessel occlusions at increasingly distal locations farther in time from stroke onset. Accessing these smaller vessels raises the concern of iatrogenic subarachnoid hemorrhage (SAH) owing to increasing complexity in device navigation and retrieval. This study aims to determine the prevalence of SAH following mechanical thrombectomy, associated predictors, and resulting functional outcomes using a multicenter registry and compare this with a systematic review and meta-analysis of the literature. Methods: Data from STRATIS (The Systematic Evaluation of Patients Treated with Neurothrombectomy Devices for Acute Ischemic Stroke) registry were analyzed dichotomized by the presence or absence of SAH after thrombectomy. Only patients with 24-h post-procedural neuroimaging were included (n = 841). Multivariable logistic regression was performed to identify significant predictors of SAH. A systematic review and random-effects meta-analysis was also conducted in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) protocol. Results: The prevalence of post-thrombectomy SAH was 5.23% in STRATIS with 15.9% (1.84% overall) experiencing neurological decline. Distal location of vessel occlusion (OR 3.41 [95% CI: 1.75-6.63], p < 0.001) and more than 3 device passes (OR 1.34 [95% CI: 1.09-1.64], p = 0.01) were associated with a higher probability of SAH in contrast to a reduction with administration of intravenous tissue plasminogen activator (tPA) (OR 0.48 [95% CI: 0.26-0.89], p = 0.02). There was a trend toward a higher discharge NIHSS (8.3 ± 8.7 vs. 5.3 ± 6.6, p = 0.07) with a significantly reduced proportion achieving functional independence at 90 days (modified Rankin Score 0-2: 32.5% vs. 57.8%, p = 0.002) in SAH patients. Pooled analysis of 10,126 patients from 6 randomized controlled trials and 64 observational studies demonstrated a prevalence of 5.85% [95% CI: 4.51-7.34%, I ²: 85.2%]. Only location of vessel occlusion was significant for increased odds of SAH at distal sites (OR 2.89 [95% CI: 1.14, 7.35]). Conclusions: Iatrogenic SAH related to mechanical thrombectomy is more common with treatment of distally-situated occlusions and multiple device passes. While low in overall prevalence, its effect is not benign with fewer patients reaching post-procedural functional independence, particularly if symptomatic.

Factors Associated with Poor Outcomes in Patients Undergoing Endovascular Therapy for Acute Ischemic Stroke due to Large-Vessel Occlusion in Acute Anterior Circulation: A Retrospective Study

OBJECTIVE

To investigate factors associated with poor clinical outcomes in patients with acute ischemic stroke undergoing endovascular therapy.

METHODS

A retrospective review of 265 patients with acute ischemic stroke treated in the First Hospital of Jilin University between January 1, 2016, and November 1, 2019, was performed. The primary outcome was the proportion of patients with a modified Rankin score of 0-2 at 90 days. Univariate and multivariate analyses were performed to assess potential clinical factors associated with a poor 90-day outcome.

RESULTS

The rates of successful revascularization, good prognosis, symptomatic intracranial hemorrhage, and mortality were 84.5%, 46.0%, 9.8%, and 12.8%, respectively. As per univariate analysis, age, diagnosis of atrial fibrillation, diagnosis of diabetes, high baseline glucose level, tandem occlusion, high National Institutes of Health Stroke Scale (NIHSS) score at admission, general anesthesia, number of passes, high NIHSS score on discharge, unsuccessful recanalization (modified treatment in cerebral ischemia score <2b), and development of symptomatic intracranial hemorrhage, hemorrhagic infarction, parenchymal hematoma, and subarachnoid hemorrhage were associated with poor prognosis. Tobacco use was positive in correlation with good prognosis in univariate analysis. Diabetes, tandem occlusion, high NIHSS score at admission, and general anesthesia were independent factors associated with a poor 90-day outcome in multivariate analysis.

CONCLUSIONS

Diabetes, tandem occlusion, high NIHSS score at admission, and general anesthesia were independent risk factors associated with a poor 90-day outcome and should be considered a reference by neurointerventionalists in guiding their clinical decision-making.

Intracranial Bleeding After Reperfusion Therapy in Acute Ischemic Stroke

Intracranial hemorrhage is one of the most feared complications following brain infarct. Ischemic tissues have a natural tendency to bleed. Moreover, the first recanalization trials using intravenous thrombolysis have shown an increase in mild to severe intracranial hemorrhage. Symptomatic intracerebral hemorrhage is strongly associated with poor outcomes and is an important factor in recanalization decisions. Stroke physicians have to weigh the potential benefit of recanalization therapies, first, with different risks of intracranial hemorrhage described in randomized controlled trials, and second with numerous risk markers that have been found to be associated with intracranial hemorrhage in retrospective series. These decisions have become quite complex with different intravenous thrombolytics and mechanical thrombectomy. This review aims to outline some elements of the pathophysiological mechanisms and classifications, describe most of the risk factors identified for each reperfusion therapy, and finally suggest future research directions that could help physicians dealing with these complications.

Comparision of Mechanical Thrombectomy With Contact Aspiration or Stent Retriever in Patients With Large-vessel Occlusion in Acute Ischemic Stroke

OBJECTIVES

Whether the direct aspiration approach of thrombectomy for recanalization in patients with acute ischemic stroke has a similar efficacy and safety compared to the stent-retriever still remains uncertain.

METHODS

A retrospective data analysis was performed to identify patients with large cerebral artery acute ischemic stroke treated with endovascular thrombectomy. The study was conducted between January 2018 and December 2019 in a single stroke center.

RESULTS

Twenty patients met inclusion criteria for this study with a mean age 66.64 ± 17.92 years' old. The symptom occurred on the left side were in 13, and the right side in 7. The location of occlusion was 8 in M1 of the middle cerebral artery of M2, and 6 in internal carotid artery. Nine patients were randomized to first-line treatment with contact aspiration and eleven to first-line treatment with a stent retriever. The mean time from admission time to groin puncture was 55.51 ± 31.03 minutes. The average time from groin puncture to maximal revascularizion after mechanical thrombectomy was 50.9 ± 22.5 minutes in contact aspiration group, but this time was 71.37 ± 25.45 minutes in the group of stent retriever. The overall successful revascularization rate (TICI 2b-3) was 88.9% in contact aspiration (TICI2a = 1, TICI 2b = 4 patients, TICI 3 = 4 patients), and 90.1% in stent retriever (TICI2a = 1, TICI 2b = 6 patients, TICI 3 = 4 patients).

DISCUSSION

First-line thrombectomy with contact aspiration did not result in a higher successful revascularization rate at the end of the procedure but had a short time from groin puncture to maximal revascularizion.