Prognosis associated with asymptomatic intracranial hemorrhage after acute ischemic stroke: a systematic review and meta-analysis

Endovascular Stroke Thrombectomy for Patients With Large Ischemic Core: A Review

Importance

Recently, 6 randomized clinical trials-RESCUE-Japan-LIMIT (Recovery by Endovascular Salvage for Cerebral Ultra-Acute Embolism-Japan Large Ischemic Core Trial), ANGEL-ASPECT (Trial of Endovascular Therapy for Acute Ischemic Stroke With Large Infarct), SELECT2 (Trial of Endovascular Thrombectomy for Large Ischemic Strokes), TESLA (Thrombectomy for Emergent Salvage of Large Anterior Circulation Ischemic Stroke), TENSION (Endovascular Thrombectomy for Acute Ischemic Stroke With Established Large Infarct), and LASTE (Large Stroke Therapy Evaluation)-have concluded their investigations on the efficacy and safety of endovascular thrombectomy (EVT) for the treatment of patients with ischemic stroke, anterior-circulation large vessel occlusions, and large areas of ischemic changes defined as an Alberta Stroke Program Early Computed Tomography Score (ASPECTS) of 5 or less. Overall, the results appeared to be positive, with 5 of the 6 trials meeting their primary efficacy end point, and 1 trial that was a near miss. However, questions remain regarding how these trial results should be interpreted and incorporated into routine clinical practice.

Observations

In this narrative review and analysis of published trials, important nuances of the available clinical data were identified, and important areas of lingering uncertainty were highlighted, including the efficacy and safety of EVT for patients with a low ASPECTS score in late treatment windows and those with large core volumes. Also emphasized was the possibly important role of advanced neuroimaging modalities such as perfusion and magnetic resonance imaging when making EVT treatment decisions for select patients with low ASPECTS scores.

Conclusions and Relevance

Recent trial data provide strong evidence that EVT is safe and effective for patients with anterior, large vessel-occlusion stroke and low ASPECTS scores who present within 6 hours from stroke onset. However, patient outcomes often remain poor despite EVT treatment. The efficacy and safety of EVT for patients with low ASPECTS scores who present beyond 6 hours of stroke onset remain uncertain, and the current trial data seem too scarce to justify forgoing advanced stroke imaging during this extended time window. Furthermore, the efficacy and safety of EVT for patients with large core volumes (100 mL or greater) or M2 occlusions (ie, occlusions of the second segment of the middle cerebral artery) remain uncertain. Future research to better identify patients likely to meaningfully respond to EVT is needed to further optimize the stroke triage process and health care resource utilization.

Acute ischemic stroke with or without asymptomatic intracranial hemorrhage after endovascular treatment: a propensity-score matching study

BACKGROUND

The long-term follow-up of asymptomatic intracranial hemorrhage (aICH) in patients with acute ischemic stroke after endovascular treatment (EVT) remains controversial.ObjectiveTo evaluate the potential effect of aICH in a real-world practice setting using a matched prospective database.

METHODS

This observational cohort study enrolled patients between January 2015 and December 2022 in a prospective database. Eligible patients with occlusions in the anterior circulation were given endovascular treatment and achieved successful reperfusion. The primary outcome was functional independence (modified Rankin Scale (mRS) score 0-2). Propensity score (PS)-weighted multivariable logistic regression analyses were adjusted and were repeated in subsequent 1:1 PS-matched cohorts.

RESULTS

732 patients, 516 without any ICH and 216 with aICH, were included. 418 and 348 patients were identified after matching in the aICH substudy and hemorrhagic infarction type aICH substudy, respectively. In the postmatched population, patients with aICH had worse functional outcomes (mRS score 0-2) at 90 days than patients without any ICH (37.8% vs 55.5%: P<0.001). Worse functional outcomes were seen in patients with aICH who were older (OR=5.59 (95% CI 2.91 to 10.74)), had higher baseline National Institutes of Health Stroke Scale score (OR=6.80 (95% CI 3.72 to 12.43)), lower baseline Alberta Stroke Program Early CT Score (OR=2.08 (95% CI 1.23 to 3.51)), and who received general anesthesia (OR=3.37 (95% CI 1.92 to 5.90)).

CONCLUSIONS

This matched-control study largely confirmed that asymptomatic ICH after EVT is associated with worse functional outcomes, and the harmful effect is more significant in older patients and those with severe baseline clinical and radiological features.

Early Versus Late Initiation of Direct Oral Anticoagulants After Ischemic Stroke in People With Atrial Fibrillation and Hemorrhagic Transformation: Prespecified Subanalysis of the Randomized Controlled ELAN Trial

BACKGROUND

Whether hemorrhagic transformation (HT) modifies the treatment effect of early compared with late initiation of direct oral anticoagulation in people with ischemic stroke and atrial fibrillation is unknown.

METHODS

This is a post hoc analysis of the ELAN trial (Early Versus Late Initiation of Direct Oral Anticoagulants in Post-Ischaemic Stroke Patients With Atrial Fibrillation). The primary outcome was a composite of recurrent ischemic stroke, symptomatic intracranial hemorrhage, major extracranial bleeding, systemic embolism, or vascular death within 30 days. Secondary outcomes were the individual components, 30- and 90-day functional outcome. We estimated outcomes based on HT, subclassified as hemorrhagic infarction (HI) or parenchymal hemorrhage (PH) on prerandomization imaging (core laboratory rating) using adjusted risk differences between treatment arms.

RESULTS

Overall, 247 of 1970 participants (12.5%) had HT (114 HI 1, 77 HI 2, 34 PH 1, 22 PH 2). For the primary outcome, the estimated adjusted risk difference (early versus late) was -2.2% (95% CI, -7.8% to 3.5%) in people with HT (HI: -4.7% [95% CI, -10.8% to 1.4%]; PH: 6.1% [95% CI, -8.5% to 20.6%]) and -0.9% (95% CI, -2.6% to 0.8%) in people without HT. Numbers of symptomatic intracranial hemorrhage were identical in people with and without HT. With early treatment, the estimated adjusted risk difference for poor 90-day functional outcome (modified Rankin Scale score, 3-6) was 11.5% (95% CI, -0.8% to 23.8%) in participants with HT (HI: 7.4% [95% CI, -6.4% to 21.2%]; PH: 25.1% [95% CI, 0.2% to 50.0%]) and -2.6% (95% CI, -7.1% to 1.8%) in people without HT.

CONCLUSIONS

We found no evidence of major treatment effect heterogeneity or safety concerns with early compared with late direct oral anticoagulation initiation in people with and without HT. However, early direct oral anticoagulation initiation may worsen functional outcomes in people with PH.

REGISTRATION

URL: http://www.clinicaltrials.gov; Unique identifier: NCT03148457.

Influencing factors of futile recanalization after endovascular intervention in patients with acute basilar artery occlusion

OBJECTIVES

To explore the influence factors for futile recanalization following endovascular treatment (EVT) in patients with acute basilar artery occlusion (BAO).

METHODS

Clinical data of patients with acute BAO, who underwent endovascular treatment within 24 h of onset from January 2017 to November 2022, were retrospectively analyzed. The futile recanalization was defined as modified thrombolysis in cerebral infarction (mTICI) grade ≥2b or 3 after successful reperfusion, but the modified Rankin Scale score >2 at 3 months after EVT. Binary logistic regression model was used to analyze the influencing factors of futile recanalization.

RESULTS

A total of 471 patients with a median age of 68 (57, 74) years were included and 68.9% were males, among whom 298 (63.27%) experienced futile recanalization. Multivariate analysis revealed that concomitant atrial fibrillation (OR=0.456, 95%CI: 0.282-0.737, P<0.01), bridging thrombolysis (OR=0.640, 95%CI: 0.416-0.985, P<0.05), achieving mTICI grade 3 (OR=0.554, 95%CI: 0.334-0.918, P<0.05), arterial occlusive lesion (AOL) grade 3 (OR=0.521, 95%CI: 0.326-0.834, P<0.01), and early postoperative statin therapy (OR=0.509, 95%CI: 0.273-0.948, P<0.05) were protective factors for futile recanalization after EVT in acute BAO patients. High baseline National Institutes of Health Stroke Scale (NIHSS) score (OR=1.068, 95%CI: 1.049-1.087, P<0.01), coexisting hypertension (OR=1.571, 95%CI: 1.017-2.427, P<0.05), multiple retrieval attempts (OR=1.237, 95%CI: 1.029-1.488, P<0.05) and postoperative hemorrhagic transformation (OR=8.497, 95%CI: 2.879-25.076, P<0.01) were risk factors. For trial of ORG 10172 in acute stroke treatment (TOAST) classification, cardiogenic embolism (OR=0.321, 95%CI: 0.193-0.534, P<0.01) and other types (OR=0.499, 95%CI: 0.260-0.961, P<0.05) were related to lower incidence of futile recanalization.

CONCLUSIONS

The incidence of futile recanalization after EVT in patients with acute BAO is high. Bridging venous thrombolysis before operation and an early postoperative statin therapy may reduce the incidence of futile recanalization.

Parabiosis Discriminates the Circulating, Endothelial, and Parenchymal Contributions of Endogenous Tissue-Type Plasminogen Activator to Stroke

BACKGROUND

Intravenous injection of alteplase, a recombinant tPA (tissue-type plasminogen activator) as a thrombolytic agent has revolutionized ischemic stroke management. However, tPA is a more complex enzyme than expected, being for instance able to promote thrombolysis, but at the same time, also able to influence neuronal survival and to affect the integrity of the blood-brain barrier. Accordingly, the respective impact of endogenous tPA expressed/present in the brain parenchyma versus in the circulation during stroke remains debated.

METHODS

To address this issue, we used mice with constitutive deletion of tPA (tPANull [tPA-deficient mice]) or conditional deletion of endothelial tPA (VECad [vascular endothelial-Cadherin-Cre-recombinase]-Cre∆tPA). We also developed parabioses between tPANull and wild-type mice (tPAWT), anticipating that a tPAWT donor would restore levels of tPA to normal ones, in the circulation but not in the brain parenchyma of a tPANull recipient. Stroke outcomes were investigated by magnetic resonance imaging in a thrombo-embolic or a thrombotic stroke model, induced by local thrombin injection or FeCl3 application on the endothelium, respectively.

RESULTS

First, our data show that endothelial tPA, released into the circulation after stroke onset, plays an overall beneficial role following thrombo-embolic stroke. Accordingly, after 24 hours, tPANull/tPANull parabionts displayed less spontaneous recanalization and reperfusion and larger infarcts compared with tPAWT/tPAWT littermates. However, when associated to tPAWT littermates, tPANull mice had similar perfusion deficits, but less severe brain infarcts. In the thrombotic stroke model, homo- and hetero-typic parabionts did not differ in the extent of brain damages and did not differentially recanalize and reperfuse.

CONCLUSIONS

Together, our data reveal that during thromboembolic stroke, endogenous circulating tPA from endothelial cells sustains a spontaneous recanalization and reperfusion of the tissue, thus, limiting the extension of ischemic lesions. In this context, the impact of endogenous parenchymal tPA is limited.

Asymptomatic Intracerebral Hemorrhage Following Endovascular Stroke Therapy Is Not Benign: A Systematic Review and Meta-Analysis

BACKGROUND

Asymptomatic intracerebral hemorrhage (aICH) occurs in approximately 35% of patients with acute ischemic stroke after endovascular thrombectomy. Unlike symptomatic ICH, studies evaluating the effect of aICH on outcomes have been inconclusive. We performed a systematic review and meta-analysis to evaluate the long-term effects of postendovascular thrombectomy aICH.

METHODS AND RESULTS

The meta-analysis protocol was submitted to the International Prospective Register of Systematic Reviews a priori. PubMed, Scopus, and Web of Science were searched from inception through September 2023, yielding 312 studies. Two authors independently reviewed all abstracts. Included studies contained adult patients with ischemic stroke undergoing endovascular thrombectomy with follow-up imaging assessment of ICH reporting comparative outcomes according to aICH versus no ICH. After screening, 60 papers were fully reviewed, and 10 studies fulfilled inclusion criteria (n=5723 patients total, 1932 with aICH). Meta-analysis was performed using Cochrane RevMan v5.4. Effects were estimated by a random-effects model to estimate summary odds ratio (OR) of the effect of aICH versus no ICH on primary outcomes of 90-day modified Rankin Scale 3 to 6 and mortality. The presence of aICH was associated with a higher odds of 90-day mRS 3 to 6 (OR, 2.17 [95% CI, 1.81-2.60], P<0.0001, I2 46% Q 19.15) and mortality (OR, 1.72 [95% CI, 1.17-2.53], P:0.005, I2 79% Q 27.59) compared with no ICH. This difference was maintained following subgroup analysis according to hemorrhage classification and recanalization status.

CONCLUSIONS

The presence of aICH is associated with worse 90-day functional outcomes and higher mortality. Further studies to evaluate the factors predicting aICH and treatments aimed at reducing its occurrence are warranted.

Asymptomatic parenchymal haemorrhage following endovascular treatment: Impact on functional outcome in patients with acute ischaemic stroke

BACKGROUND AND PURPOSE

In patients with acute ischaemic stroke (AIS), haemorrhagic transformation (HT) following endovascular treatment (EVT) is associated with poor functional outcome. However, the impact of asymptomatic HT, not linked to neurological deterioration in the acute phase, is unknown. We aimed to investigate the impact of asymptomatic PH1 (aPH1) and PH2 (aPH2) subtypes of HT on the functional outcome of patients treated with EVT.

METHODS

We conducted a retrospective study of patients with AIS who were consecutively admitted to our comprehensive stroke centre between January 2019 and December 2022, and who underwent EVT. We collected clinical, radiological, and procedural data. HTs were categorized according to the Heidelberg classification. The primary outcome was the shift on the modified Rankin Scale (mRS) at 3 months of follow-up. We performed bivariate and multivariable ordinal regression analyses to test the association between aPH1/aPH2 and the primary outcome.

RESULTS

We included 314 patients (mean age = 72.5 years [SD = 13.6], 171 [54.5%] women). We detected 54 (17.2%) patients with HT; 23 (7.3%) were classified as PH2 (11 asymptomatic) and 17 (5.4%) as PH1 (16 asymptomatic). The adjusted common odds ratio for aPH2 of worsening 1 point on the 3-month mRS was 3.32 (95% confidence interval = 1.16-9.57, p = 0.026). No association was observed for aPH1. aPH2 was also independently associated with lower odds of achieving a favourable outcome (mRS = 0-2). Neither aPH1 nor aPH2 was associated with mortality.

CONCLUSIONS

In patients with AIS treated with EVT, aPH2 is independently associated with unfavourable functional outcome.

Risk factors and predictors of intracranial hemorrhage after mechanical thrombectomy in acute ischemic stroke: insights from the Stroke Thrombectomy and Aneurysm Registry (STAR)

BACKGROUND

Reducing intracranial hemorrhage (ICH) can improve patient outcome in acute ischemic stroke (AIS) intervention. We sought to identify ICH risk factors after AIS thrombectomy.

METHODS

This is a retrospective review of the Stroke Thrombectomy and Aneurysm Registry (STAR) database. All patients who underwent AIS thrombectomy with available ICH data were included. Multivariable regression models were developed to identify predictors of ICH after thrombectomy. Subgroup analyses were performed stratified by symptom status and European Cooperative Acute Stroke Study (ECASS) grade.

RESULTS

The study cohort comprised 6860 patients. Any ICH and symptomatic ICH (sICH) occurred in 25% and 7% of patients, respectively. Hemorrhagic infarction 1 (HI1) occurred in 36%, HI2 in 24%, parenchymal hemorrhage 1 (PH1) in 22%, and PH2 in 17% of patients classified by ECASS grade. Intraprocedural complications independently predicted any ICH (OR 3.8083, P<0.0001), PH1 (OR 1.9053, P=0.0195), and PH2 (OR 2.7347, P=0.0004). Race also independently predicted any ICH (black: OR 0.5180, P=0.0017; Hispanic: OR 0.4615, P=0.0148), sICH (non-white: OR 0.4349, P=0.0107), PH1 (non-white: OR 3.1668, P<0.0001), and PH2 (non-white: OR 1.8689, P=0.0176), with white as the reference. Primary mechanical thrombectomy technique also independently predicted ICH. ADAPT (A Direct Aspiration First Pass Technique) was a negative predictor of sICH (OR 0.2501, P<0.0001), with stent retriever as the reference.

CONCLUSIONS

This study identified ICH risk factors after AIS thrombectomy using real-world data. There was a propensity towards a reduced sICH risk with direct aspiration. Procedural complications and ethnicity were predictors congruent between categories of any ICH, sICH, PH1, and PH2. Further investigation of technique and ethnicity effects on ICH and outcomes after AIS thrombectomy is warranted.

OEDL: an optimized ensemble deep learning method for the prediction of acute ischemic stroke prognoses using union features

Background

Early stroke prognosis assessments are critical for decision-making regarding therapeutic intervention. We introduced the concepts of data combination, method integration, and algorithm parallelization, aiming to build an integrated deep learning model based on a combination of clinical and radiomics features and analyze its application value in prognosis prediction.

Methods

The research steps in this study include data source and feature extraction, data processing and feature fusion, model building and optimization, model training, and so on. Using data from 441 stroke patients, clinical and radiomics features were extracted, and feature selection was performed. Clinical, radiomics, and combined features were included to construct predictive models. We applied the concept of deep integration to the joint analysis of multiple deep learning methods, used a metaheuristic algorithm to improve the parameter search efficiency, and finally, developed an acute ischemic stroke (AIS) prognosis prediction method, namely, the optimized ensemble of deep learning (OEDL) method.

Results

Among the clinical features, 17 features passed the correlation check. Among the radiomics features, 19 features were selected. In the comparison of the prediction performance of each method, the OEDL method based on the concept of ensemble optimization had the best classification performance. In the comparison to the predictive performance of each feature, the inclusion of the combined features resulted in better classification performance than that of the clinical and radiomics features. In the comparison to the prediction performance of each balanced method, SMOTEENN, which is based on a hybrid sampling method, achieved the best classification performance than that of the unbalanced, oversampled, and undersampled methods. The OEDL method with combined features and mixed sampling achieved the best classification performance, with 97.89, 95.74, 94.75, 94.03, and 94.35% for Macro-AUC, ACC, Macro-R, Macro-P, and Macro-F1, respectively, and achieved advanced performance in comparison with that of methods in previous studies.

Conclusion

The OEDL approach proposed herein could effectively achieve improved stroke prognosis prediction performance, the effect of using combined data modeling was significantly better than that of single clinical or radiomics feature models, and the proposed method had a better intervention guidance value. Our approach is beneficial for optimizing the early clinical intervention process and providing the necessary clinical decision support for personalized treatment.

Proximal hyperdense middle cerebral artery sign is associated with increased risk of asymptomatic hemorrhagic transformation after endovascular thrombectomy: a multicenter retrospective study

OBJECTIVE

To investigate whether hyperdense middle cerebral artery sign (HMCAS) on pretreatment no-contrast CT (NCCT) is associated with hemorrhagic transformation (HT) after endovascular thrombectomy (EVT).

METHODS

Patients with acute middle cerebral artery (MCA) occlusion who received EVT in three comprehensive hospitals were retrospectively evaluated. They were divided into four groups based on the presence or absence of HMCAS and corresponding CTA findings, among whom differences were compared. Univariate and multivariate logistic regression analyses were performed to investigate the association between HMCAS and HT and its subtypes.

RESULTS

318 patients were included, among whom 149 (46.9%) had HMCAS. Patients in the proximal positive HMCAS group had higher National Institute of Health Stroke Scale scores and lower Alberta Stroke Program Early CT Scores (ASPECTS) than those in the proximal negative HMCAS group. The rate of HT was higher in the proximal positive HMCAS group than that in the proximal negative HMCAS group. In multivariate logistic regression analysis, the proximal HMCAS were independently associated with HT (adjusted OR = 2.073, 95% CI 1.211-3.551, p = 0.008) and aHT (adjusted OR = 2.271, 95% CI 1.294-3.986, p = 0.004), but not with sHT. Patients who developed HT, including aHT and sHT, had a lower rate of good outcome.

CONCLUSION

Proximal HMCAS on initial NCCT was independently associated with aHT in patients who received EVT for acute MCA occlusion. Both aHT and sHT had a detrimental effect on clinical outcome.

Geriatric Nutritional Risk Index and the Prognosis of Patients with Stroke: A Meta-Analysis

Malnutrition evidenced by low geriatric nutritional risk index (GNRI) has been suggested as a potential predictor of poor prognosis of patients with various clinical conditions. We performed a meta-analysis to systematically assess the association between GNRI and the prognosis of patients after stroke. Cohort studies were identified by search of PubMed, Embase, Cochrane's Library and Web of Science databases from inception to March 25, 2022, according to the aim of the meta-analysis. A random-effect model incorporating the potential between-study heterogeneity was used to pool the results. Eight cohort studies with 13573 patients with stroke contributed to the meta-analysis. Pooled results showed that malnutrition as evidenced by low GNRI was independently associated with a higher risk of poor functional outcome [risk ratio (RR): 1.54, 95% confidence interval (CI): 1.19 to 1.98, p<0.001; I2=69%] and an increased incidence of all-cause mortality (RR: 1.82, 95% CI: 1.35 to 2.47, p<0.001; I2=74%). Sensitivity analyses showed consistent results in patients with ischemic stroke, and in prospective cohort studies. Subgroup analyses showed that the associations were not significant for patients with GNRI-defined mild malnutrition (p=0.18 and 0.20 for functional and mortality outcomes, respectively), but significant for patients with moderate-severe malnutrition (both p<0.001). Difference in follow-up durations did not significantly affect the associations (p for subgroup difference=0.75 and 0.70, respectively). In conclusion, a low GNRI is associated with poor functional and survival outcomes in patients after stroke.