Impact of thrombocytopenia on hemorrhagic complications after endovascular therapy for acute large vessel occlusion: Sub-analysis of RESCUE-Japan registry 2

BACKGROUND

Endovascular treatment (EVT) for patients with large vessel occlusion (LVO) and concurrent thrombocytopenia raises concerns about hemorrhagic complications. We examined the association between thrombocytopenia and clinical outcomes after EVT.

METHODS

This is a sub-analysis of the RESCUE-Japan Registry 2, a nationwide registry that enrolled 2420 consecutive acute LVO patients. We evaluated the clinical outcomes in patients who underwent EVT according to their platelet count on admission (Moderate/Severe, < 100 × 10⁹ /L; Mild, 100 to ≤150 × 10⁹/L; Normal, ≥ 150 × 10⁹/L). The outcomes included any and symptomatic intracranial hemorrhage (ICH) after EVT, and modified Rankin Scale (mRS) at 90 days.

RESULTS

Of 1268 patients who underwent EVT, the Moderate/Severe and Mild groups consisted of 41 (3.2%), and 193 (15.2%) patients. Any ICH occurred in 37%, 35%, and 24% of Moderate/Severe, Mild, and Normal group patients, respectively, and the adjusted ORs (95% CIs) were 1.50 (0.71-3.18) for Moderate/Severe and 1.87 (1.28-2.73) for Mild, compared to the Normal group (p for trend = 0.004). Symptomatic ICH increased with the severity of thrombocytopenia (9.8% vs 3.6% vs 2.1%), and adjusted ORs were 4.43 (1.16-17.0) in Moderate/Severe and 1.85 (0.71-4.86) in Mild (p for trend = 0.10). Mortality was significantly associated with the severity of thrombocytopenia (p for trend = 0.005), and adjusted ORs were 3.26 (1.29-8.26) in the Moderate/Severe and 2.76 (1.58-4.84) in the Mild groups.

CONCLUSIONS

Thrombocytopenia in LVO patients was not rare and associated with the incidence and manifestation of ICH after EVT.

Prediction of blood pressure variability during thrombectomy using supervised machine learning and outcomes of patients with ischemic stroke from large vessel occlusion

Mechanical thrombectomy (MT) is the standard of care for patients with acute ischemic stroke from large vessel occlusion (AIS-LVO). The association of blood pressure variability (BPV) during MT and outcomes are unknown. We leveraged a supervised machine learning algorithm to predict patient characteristics that are associated with BPV indices. We performed a retrospective review of our comprehensive stroke center's registry of all adult patients undergoing MT between 01/01/2016 and 12/31/2019. The primary outcome was poor functional independence, defined as 90-day modified Rankin Scale (mRS) ≥ 3. We used probit analysis and multivariate logistic regressions to evaluate the association of patients' clinical factors and outcomes. We applied a machine learning algorithm (random forest, RF) to determine predictive factors for the different BPV indices during MT. Evaluation was performed with root-mean-square error (RMSE) and normalized-RMSE (nRMSE) metrics. We analyzed 375 patients with mean age (± standard deviation [SD]) of 65 (15) years. There were 234 (62%) patients with mRS ≥ 3. Univariate probit analysis demonstrated that BPV during MT was associated with poor functional independence. Multivariable logistic regression showed that age, admission National Institutes of Health Stroke Scale (NIHSS), mechanical ventilation, and thrombolysis in cerebral infarction (TICI) score (OR 0.42, 95% CI 0.17-0.98, P = 0.044) were significantly associated with outcome. RF analysis identified that the interval from last-known-well time-to-groin puncture, age, and mechanical ventilation were among important factors significantly associated with BPV. BPV during MT was associated with functional outcome in univariate probit analysis but not in multivariable regression analysis, however, NIHSS and TICI score were. RF algorithm identified risk factors influencing patients' BPV during MT. While awaiting further studies' results, clinicians should still monitor and avoid high BPV during thrombectomy while triaging AIS-LVO candidates quickly to MT.

Association between intravenous tirofiban and intracranial hemorrhage in acute large vessel occlusion stroke: insight from the RESCUE BT randomized placebo-controlled trial

BACKGROUND

The aim of this study is to investigate the association between intravenous tirofiban and symptomatic intracranial hemorrhage (SICH) in patients with acute ischemic stroke (AIS) secondary to large vessel occlusion (LVO) receiving endovascular thrombectomy (EVT) within 24 h of time last known well (LKW).

METHODS

Patients with AIS-LVO who were randomly assigned to receive intravenous tirofiban or placebo before EVT within 24 h of time LKW and had follow-up brain non-contrast computed tomography within 24 h after stopping tirofiban treatment were derived from "RESCUE BT": a multicenter, randomized, placebo-controlled, double-blind trial. All eligible patients were divided into SICH and NO-SICH groups. Subgroup analyses were performed to explore for heterogeneity.

RESULTS

Of 945 patients included in this cohort, there were 76 (8.0%) in the SICH group and 869 (92.0%) in the NO-SICH group. The incidence of SICH was not higher in patients receiving intravenous tirofiban compared with placebo (adjusted risk ratio (RR), 1.51; 95% confidence interval (CI), 0.97-2.36; P = 0.07). Subgroup analyses showed that age greater than 67-year-old (adjusted RR, 2.18; 95% CI 1.18-4.00), NIHSS greater than 16 (adjusted RR, 1.88; 95% CI 1.06-3.34), and cardioembolism (adjusted RR, 3.73; 95% CI 1.66-8.35) were associated with increased SICH risk.

CONCLUSIONS

In patients with acute large vessel occlusion stroke, intravenous tirofiban before EVT within 24 h of time from last known well is not associated with increased risk of SICH. Patients who are older, have more severe neurological deficits, or with cardioembolism are at higher risk of SICH with intravenous tirofiban.

TRIAL REGISTRATION NUMBER

URL: http://www.chictr.org.cn ; Unique identifier: ChiCTR-INR-17014167.

SELF-SUPERVISED LEARNING WITH RADIOLOGY REPORTS, A COMPARATIVE ANALYSIS OF STRATEGIES FOR LARGE VESSEL OCCLUSION AND BRAIN CTA IMAGES

Scarcity of labels for medical images is a significant barrier for training representation learning approaches based on deep neural networks. This limitation is also present when using imaging data collected during routine clinical care stored in picture archiving communication systems (PACS), as these data rarely have attached the high-quality labels required for medical image computing tasks. However, medical images extracted from PACS are commonly coupled with descriptive radiology reports that contain significant information and could be leveraged to pre-train imaging models, which could serve as starting points for further task-specific fine-tuning. In this work, we perform a head-to-head comparison of three different self-supervised strategies to pre-train the same imaging model on 3D brain computed tomography angiogram (CTA) images, with large vessel occlusion (LVO) detection as the downstream task. These strategies evaluate two natural language processing (NLP) approaches, one to extract 100 explicit radiology concepts (Rad-SpatialNet) and the other to create general-purpose radiology reports embeddings (DistilBERT). In addition, we experiment with learning radiology concepts directly or by using a recent self-supervised learning approach (CLIP) that learns by ranking the distance between language and image vector embeddings. The LVO detection task was selected because it requires 3D imaging data, is clinically important, and requires the algorithm to learn outputs not explicitly stated in the radiology report. Pre-training was performed on an unlabeled dataset containing 1,542 3D CTA - reports pairs. The downstream task was tested on a labeled dataset of 402 subjects for LVO. We find that the pre-training performed with CLIP-based strategies improve the performance of the imaging model to detect LVO compared to a model trained only on the labeled data. The best performance was achieved by pre-training using the explicit radiology concepts and CLIP strategy.

Mechanical thrombectomy for acute large vessel occlusion stroke beyond 24 h

BACKGROUND

Multiple trials have shown that mechanical thrombectomy (MT) is superior to medical therapy. However, no robust evidence is available regarding MT beyond 24 h. In this study, we aimed to determine the safety and efficacy of endovascular stroke therapy in this late window.

METHODS

We conducted a retrospective study of prospectively collected data of patients who met extended window trial criteria, but underwent MT beyond 24 h. Safety and efficacy outcomes included symptomatic intracerebral hemorrhage (sICH), procedural complications, number of passes, successful recanalization (mTICI 2b - 3), delta (Δ) NIHSS (baseline-discharge), and favorable outcomes (mRS 0-2 at 90 days).

RESULTS

A total of 39 patients were included with a median age of 69 years (IQR 61.5, 73.5); 54% were females. Hypertension was present in 76% of patients; 23% were smokers. Half of the patients had M1 occlusion (48.7%). Median preprocedural NIHSS was 11 (IQR 7.0, 19.5). Successful revascularization was achieved in 87%; median number of passes was 2 (IQR 1.0, 3.0). Median ΔNIHSS was 3.0 (IQR -1.5, 8.0). Favorable outcome was achieved in 49% (95% CI: 34%-64%), and 95% were free of complications. A total of 3 patients (7.7%) had sICH. In an exploratory analysis, posterior circulation occlusion was associated with higher mRS at 90 days (OR: 14.7, p = 0.016). Favorable discharge facility was associated with lower mRS at 90 days (OR: 0.11, p = 0.004).

CONCLUSIONS

Our study showed comparable clinical outcomes of MT beyond 24 h compared to MT trials within 24 h in patients with favorable imaging profile, especially in anterior circulation occlusions.

Efficacy and Safety of the Soft Torqueable Catheter Optimized For Intracranial Access in the Endovascular Treatment of Acute Ischemic Stroke: A Meta-Analysis

OBJECTIVE

Acute ischemic stroke (AIS) is a severe, life-threatening type of stroke with poor prognosis and high recurrence rate, mainly attributed to large vessel occlusion (LVO). Improved understanding of the safety and effectiveness of the Soft Torqueable Catheter Optimized For Intracranial Access (SOFIA) for LVO-AIS might guide practitioners. Therefore, we conducted this study focusing on neurological outcomes, procedure-related complications, and recanalization rates.

METHODS

We collected data in January 2022 from PubMed, Cochrane, Web of Science, and Embase. The study considered that assessed the effects of the SOFIA catheter in treatment of LVO-AIS. We extracted data narratively and expressed the results with the proportions and 95% confidence intervals (CI).

RESULTS

We included 17 studies reporting on 2106 patients treated with the SOFIA catheter. The successful recanalization rate was 77% (95% CI, 71%-83%) with the SOFIA catheter alone and the application of a rescue stent-retriever was observed in 28% (95% CI, 23%-33%) of cases, resulting in an overall successful recanalization rate of 90% (95% CI, 87%-92%). A pooled estimate of 45% (95% CI, 39%-51%) was observed for functional independence at 90 days, 15% (95% CI, 11%-20%) for mortality at 90 days, and 5% (95% CI, 3%-8%) for symptomatic intracranial hemorrhage.

CONCLUSIONS

This meta-analysis revealed that aspiration thrombectomy with the SOFIA catheter is a safer and effective treatment modality for LVO-AIS.

Outcomes following thrombectomy for acute large vessel occlusion beyond 24 hours or with unknown time of onset

BACKGROUND

Endovascular thrombectomy (EVT) is recommended in medically eligible patients with large vessel occlusions (LVO) within 24 hours of symptom onset. While there is evidence that EVT ≥24h after last known well (LKW) is associated with favorable outcomes in patients who meet DAWN/DEFUSE-3 criteria, it is unknown if more liberal criteria can be applied.

METHODS

A single center, prospective observational cohort of consecutive adult stroke patients was queried for symptomatic occlusions of the internal carotid (ICA) or proximal middle cerebral (M1) arteries (October 2019-January 2022), with a National Institutes of Health Stroke Scale (NIHSS) ≥6, pre-stroke modified Rankin Scale (mRS) 0-2, and Alberta Stroke Program Early Computed Tomography Scale score 3-10. These inclusion criteria were extrapolated from recently published data indicating a benefit with EVT with more liberal patient selection. Patients who underwent EVT ≥24h after LKW were compared against those treated medically. The primary outcome was a good functional outcome (90-day mRS 0-2), which was evaluated using multivariable logistic regression.

RESULTS

Of the 27 included patients, the median age was 65y (IQR 49-76) with a median NIHSS of 15 (IQR 8-26), and 17 (63.0%) underwent EVT (median LKW-to-puncture 35.5h (IQR 26.9-65.8h). The primary outcome was no different with EVT in unadjusted regression (OR 1.17, 95%CI 0.17-8.09), and there remained no association across all multivariable models tested. Age, pre-stroke disability, and M1 occlusions were non-significantly associated with the primary outcome (p>0.05). There was a non-significant trend indicating a favorable shift in 90-day mRS with EVT (proportional OR 2.04, 95%CI 0.44-9.48).

CONCLUSIONS

Using more liberal inclusion criteria for EVT in the ultra-extended window, there was no statistically significant difference in the rate of good functional outcome with EVT. Larger studies are called upon to evaluate outcomes when more liberal criteria are used to assess thrombectomy eligibility.

Effect of Comorbidity Burden and Polypharmacy on Poor Functional Outcome in Acute Ischemic Stroke

PURPOSE

Comorbidities and polypharmacy are risk factors for worse outcome in stroke. However, comorbidities and polypharmacy are mostly studied separately with various approaches to assess them. We aimed to analyze the impact of comorbidity burden and polypharmacy on functional outcome in acute ischemic stroke (AIS) patients undergoing mechanical thrombectomy (MT).

METHODS

Acute ischemic stroke patients with large vessel occlusion (LVO) treated with MT from a prospective observational study were analyzed. Relevant comorbidity burden was defined as a Charlson Comorbidity Index (CCI) score ≥ 2, polypharmacy as the intake of ≥ 5 medications at time of stroke onset. Favorable outcome was a score of 0-2 on the modified Rankin scale at 90 days after stroke. The effect of comorbidity burden and polypharmacy on favorable outcome was studied via multivariable regression analysis.

RESULTS

Of 903 patients enrolled, 703 AIS patients (mean age 73.4 years, 54.9% female) with anterior circulation LVO were included. A CCI ≥ 2 was present in 226 (32.1%) patients, polypharmacy in 315 (44.8%) patients. Favorable outcome was less frequently achieved in patients with a CCI ≥ 2 (47, 20.8% vs. 172, 36.1%, p < 0.001), and in patients with polypharmacy (69, 21.9% vs. 150, 38.7%, p < 0.001). In multivariable regression analysis including clinical covariates, a CCI ≥ 2 was associated with lower odds of favorable outcome (odds ratio, OR 0.52, 95% confidence interval, 95% CI 0.33-0.82, p = 0.005), while polypharmacy was not (OR 0.81, 95% CI 0.52-1.27, p = 0.362).

CONCLUSION

Relevant comorbidity burden and polypharmacy are common in AIS patients with LVO, with comorbidity burden being a risk factor for poor outcome.

Evaluation of computed tomography perfusion and angiogram use in stroke evaluation for thrombectomy at a community emergency department setting

PURPOSE

Evaluate concordance of provider practices with clinical guidelines for thrombectomy screening in an emergency department (ED) via computed tomography perfusion and angiogram (CT-P/A).

METHODS

A retrospective observational study was conducted for patients 18 years or older who received a CT-P/A of the head and neck in a US Midwestern ED between September 2019 through June 2021. Healthcare system records reviewed for patient information, CT-P/A findings, and treatment decisions.

RESULTS

During study period, 68,403 patients presented to the ED with 718 (1.1%) receiving a CT-P/A. Of these patients, 105 (14.6%) were transferred to a regional facility for potential thrombectomy, with 74 (70.5%) receiving procedure, 28 (26.7%) not receiving procedure, and 3 (2.9%) with insufficient follow-up information. Of patients receiving CT-P/A, 23 met DAWN criteria for thrombectomy, with 21 (91.3%) transferred for potential thrombectomy and 20 (95.2%) receiving the procedure; in comparison, 81 patients (11.7%) did not meet all DAWN criteria and were transferred for potential thrombectomy, with 52 (64.2%) receiving procedure. Lastly, 55 patients met DEFUSE-3 criteria for thrombectomy with 49 (89.1%) being transferred for potential thrombectomy and 45 (91.8%) receiving procedure. In comparison, 53 patients who did not meet all DEFUSE-3 criteria were transferred for potential thrombectomy, with 27 (50.9%) receiving procedure.

CONCLUSIONS

This study helps to understand CT-P/A usage, especially in patients that fall outside of treatment criteria in the current thrombectomy literature. Results may have value to institutions interested in using CT-P/A as a diagnostic tool as well as institutions already incorporating it in stroke assessments.

Collateral-Core Ratio as a Novel Predictor of Clinical Outcomes in Acute Ischemic Stroke

The interaction effect between collateral circulation and ischemic core size on stroke outcomes has been highlighted in acute ischemic stroke (AIS). However, biomarkers that assess the magnitude of this interaction are still lacking. We aimed to present a new imaging marker, the collateral-core ratio (CCR), to quantify the interaction effect between these factors and evaluate its ability to predict functional outcomes using machine learning (ML) in AIS. Patients with AIS caused by anterior circulation large vessel occlusion (LVO) were recruited from a prospective multicenter study. CCR was calculated as collateral perfusion volume/ischemic core volume. Functional outcomes were assessed using the modified Rankin Scale (mRS) at 90 days. An ML model was built and tested with a tenfold cross-validation using nine clinical and four imaging variables with mRS score 3-6 as unfavorable outcomes. Among 129 patients, CCR was identified as the most important variable. The prediction model incorporating clinical factors, ischemic core volume, collateral perfusion volume, and CCR showed better discriminatory power in predicting unfavorable outcomes than the model without CCR (mean C index 0.853 ± 0.108 versus 0.793 ± 0.133, P = 0.70; mean net reclassification index 52.7% ± 32.7%, P < 0.05). When patients were divided into two groups based on their CCR value with a threshold of 0.73, unfavorable outcomes were significantly more prevalent in patients with CCR ≤ 0.73 than in those with CCR > 0.73. CCR is a robust predictor of functional outcomes, as identified by ML, in patients with acute LVO. The prediction model that incorporated CCR improved the model's ability to identify unfavorable outcomes. ClinicalTrials.gov Identifier: NCT02580097.

Acute Neurological Complications of Coronavirus Disease

The coronavirus disease (COVID-19) pandemic has impacted many lives globally. Neurologic manifestations have been observed among individuals at various stages and severity of the disease, the most common being stroke. Prompt identification of these neurologic diagnoses can affect patient management and prognosis. This article discusses the acute neuroradiological features typical of COVID-19, including cerebrovascular disease, intracerebral hemorrhage, leukoencephalopathy, and sensory neuropathies.

Emergency Angioplasty or Stenting for Stroke Patients with Intracranial Atherosclerotic Large Vessel Occlusion

AIM

Mechanical thrombectomy (MT) has become the gold standard for the treatment of large vessel occlusion (LVO) in acute ischemic stroke. However, it remains controversial whether emergency angioplasty or stenting in patients with intracranial atherosclerotic stenosis (ICAS) should be adopted. Thus, we performed a retrospective analysis of clinical data to determine whether emergency angioplasty or stenting is necessary.

METHODS

We retrospectively analyzed data from patients undergoing MT with ICAS-related LVO of the acute anterior circulation between 2017 and 2019. Eligible patients were divided into two treatment groups: those who received rescue angioplasty or stenting [Patients treated with rescue angioplasty or stenting (PTAS) group] and those who received thrombectomy alone (non-PTAS group). The primary outcomes were good prognosis at 90 days (mRS: 0-2). Mortality, symptomatic intracranial hemorrhage, and reocclusion rate were evaluated as secondary outcomes.

RESULTS

A total of 184 patients with severe stenosis after MT were enrolled, including 64 patients receiving rescue angioplasty or stenting and 120 patients without rescue angioplasty or stenting. Compared with the non-PTAS group, a better functional outcome (mRS0-2) (51.6% vs. 35.0%, adjusted odds ratio: 2.11, 95% confidence interval [CI]: 1.22-4.29; P=0.02), lower 7-day National Institutes of Health Stroke Scale [6 (3-12.75) vs. 10 (4-16); P=0.04], lower 24-h neurological deterioration rate (7.8% vs. 21.7%, P=0.02), and lower 24-h reocclusion rate were observed in the PTAS group (6.3% vs. 17.5%, P=0.03). There were no significant differences in mortality or incidence of symptomatic intracerebral hemorrhage.

CONCLUSION

Emergency angioplasty or stenting could be a safe and feasible therapeutic option with better outcomes for stroke patients with ICAS-related LVO.

Dissection-related tandem occlusion may be different from atherothrombotic tandem occlusion

OBJECTIVES

The optimal endovascular treatment for tandem occlusion in anterior circulation ischaemic stroke remains unknown. The aim of this study was to examine how the aetiology of carotid pathology, dissection versus atherothrombosis, affects clinical outcomes.

MATERIALS AND METHODS

Data was obtained from prospectively collected registries from two stroke centres between April 2016 and December 2020. Tandem cases with complete cervical internal carotid artery (ICA) occlusion or near-total occlusion (≥90% stenosis) were included. Patients were divided into two groups based on carotid pathology: dissection versus atherothrombosis.

RESULTS

A total of 134 patients were included: 36 were dissection and 98 were atherothrombosis. The dissection group had better clinical outcomes compared to the atherothrombosis group, although after adjusting for age and stroke risk factors differences were non-significant. In the non-stented cohort, the dissection patients achieved a better outcome (modified Rankin scale 0-2) than atherothrombotic patients (57% vs. 34%, p=0.04) at 90-days.

CONCLUSION

Dissection-related tandem occlusions appear to have different clinical features from atherothrombotic tandem occlusions which suggests different management strategies are needed.

Procedural and Clinical Outcome Analysis of Monoplane versus Biplane Angiography Suites in Stroke Thrombectomies

BACKGROUND

Thrombectomy is now the standard of care in the treatment of acute ischemic stroke caused by emergent large vessel occlusion. Therefore thrombectomy services have expanded from Comprehensive Stroke Centers to Thrombectomy-Capable Stroke Centers. Stroke interventions at these sites are performed in both biplane and monoplane angiography suites. It has been hypothesized that differences in these systems may affect time to successful reperfusion, with a potentially significant effect on neurologic outcomes. With an increase in TSCs, this study aims to evaluate the safety and efficacy of monoplane thrombectomy versus biplane thrombectomy.

METHODS

Patients who presented with isolated proximal middle cerebral artery M1 occlusions and underwent endovascular thrombectomy from March 2015 to August 2018 at 5 different centers within a single health system were included. Thrombectomy was performed by the same group of experienced neurointerventionalists. The primary endpoint was functional outcome as measured by the modified Rankin scale at 90 days. Secondary endpoints included recanalization grade as measured by the Thrombolysis in Cerebral Infarction score, time to final reperfusion, and incidence of hemorrhagic conversion.

RESULTS

A total of 197 patients were included in this study. Of them, 80.7% underwent thrombectomy on biplane systems. Time to final reperfusion was 10.2 minutes longer in the monoplane group but was not statistically significant (P = 0.252). There was no significant difference in the rates of favorable reperfusion (P = 0.755), hemorrhagic conversion (P = 0.580), or functional outcome at 90 days (favorable modified Rankin Scale 0-2, P = 0.210; favorable modified Rankin Scale 0-3, P = 0.697).

CONCLUSION

Despite perceived advantages of biplane systems in reducing procedural time, our study demonstrates no significant differences between systems. These data support the safety and efficacy of performing thrombectomy on monoplane systems and may also carry implications for reducing patient transfer times and potentially increasing thrombectomy access to areas of the world where biplane suites may not be available. The next step would be a prospective randomized trial comparing both systems in different settings.

Crossed Cerebellar Diaschisis Worsens the Clinical Presentation in Acute Large Vessel Occlusion

INTRODUCTION

Initial NIHSS in anterior large vessel occlusion (LVO) correlates partially with the hypoperfusion volume. We aimed at assessing the contribution of crossed cerebellar diaschisis (CCD) from the hypoperfused territory on LVO initial clinical deficit.

METHODS

CCD was retrospectively identified by brain CT perfusion imaging (CTP) in patients with anterior LVO treated by mechanical thrombectomy from January 2017 to July 2021. CCD was defined by CTP parameter alteration in the contralateral cerebellar hemisphere to the LVO. NIHSS, clinical/perfusion variables, and CCD were included in regression models to assess their interrelationships.

RESULTS

206 patients were included. CCD was present in 90 patients (69%). NIHSS scores were higher on admission and at stroke discharge among patients with CCD (17.90 ± 6.1 vs. 11.4 ± 8.4, p < 0.001; 9.6 ± 7.7 vs. 6.6 ± 7.9, p = 0.049; respectively). Patients with a CCD had higher stroke volumes (118.2 ± 60.3 vs. 69.3 ± 59.7, p < 0.001) and lower rate of known atrial fibrillation (22% vs. 41%, p = 0.021). On multivariable logistic regression, CCD independently worsened the initial NIHSS (OR 4.85 [2.37-7.33]; p < 0.001).

CONCLUSION

CCD is found in 69% of LVO on admission CTP, correlates with stroke volumes, and independently worsens initial NIHSS.

Successful endovascular thrombectomy 8 days after onset of acute ischemic stroke: A case report

Endovascular thrombectomy (EVT) is the recommended option for acute ischemic stroke (AIS) patients with large vessel occlusion (LVO) that within 6 h onset of stroke. The EVT treatment time window has been extended to 24 h in carefully selected patients by DAWN trial. Recent evidences indicated that some patients presented beyond 24 h still potentially benefit from EVT treatment. Herein, we describe one case of successful delayed EVT in a 50-year-old male AIS patient with an 8-day history of left middle cerebral artery occlusion. Before surgery, CT perfusion demonstrated a marked left hypoperfusion with penumbra volume of 127 mL and ischemic core volume of 10 mL. EVT was performed with complete recanalization and significant improvement in his neurological deficits at 90-days post-surgery follow-up. In future, more randomized clinical trials are warranted to further confirm the safety, efficacy, as well as the applicable population of delayed EVT.

Advances in Futile Reperfusion following Endovascular Treatment in Acute Ischemic Stroke due to Large Vessel Occlusion

BACKGROUND

Futile reperfusion (FR) is becoming an urgent issue for acute ischemic stroke patients who underwent endovascular treatment (EVT). Although the recanalization rate has improved after EVT, it is far from translating to increased tissue reperfusion and functional independence.

SUMMARY

Many underlying mechanisms including the "no-reflow" phenomenon, poor collateral flow, venous dysfunction, and inflammation were proposed, but the pathophysiology of FR is still unclear. Clinically, reliable predictors are still yet to be identified, and ongoing trials on shortening the time delay and cytoprotection may provide novel ideas for interventions of FR.

KEY MESSAGES

This review will summarize the latest advances in FR and hopefully shed light on potential interventions.

Delayed neurological improvement after endovascular treatment for acute large vessel occlusion: data from ANGEL-ACT registry

BACKGROUND

A subgroup of patients with acute large vessel occlusion (ALVO) may experience delayed neurological improvement (DNI) after endovascular treatment (EVT). Our study aimed to investigate the incidence and independent predictors of DNI in patients with ALVO after EVT.

METHODS

We selected subjects from ANGEL-ACT Registry. The definition of DNI is patients with ALVO who did not experience early neurological improvement (ENI) despite complete recanalization after EVT. These patients achieved a 90-day favorable outcome assessed by a modified Rankin Scale (mRS) score. We defined ENI as a ≥ 4-point decrease in the National Institutes of Health Stroke Scale (NIHSS) between baseline and 24 h or NIHSS of 0 or 1 at 24 h, with complete recanalization after EVT. We performed logistic regression analyses to determine the independent predictors of DNI.

RESULTS

Among the 1056 enrolled patients, 406 (38.4%) did not experience ENI. 106 (26.1%) patients without ENI achieved DNI. On Multivariate analysis, lower admission NIHSS score (odds ratio [OR] = 1.17,95% confidence interval [CI]: 1.11-1.23, P < 0.001), underlying ICAD (OR = 2.03, 95% CI: 1.07-3.85, P = 0.029) and absence of general anesthesia (OR = 2.13, 95% CI: 1.24-3.64, P = 0.006) were independent predictors of DNI.

CONCLUSION

DNI occurred in 26.1% of patients with ALVO who did not experience ENI after EVT. Our study identified several independent predictors of DNI that should be highly considered in daily clinical practice to improve ALVO management.

Cerebral blood flow quantification with multi-delay arterial spin labeling in ischemic stroke and the association with early neurological outcome

Restoring blood flow to brain tissue at risk of infarction is essential for tissue survival and clinical outcome. We used cerebral blood flow (CBF) quantified with multiple post-labeling delay (PLD) pseudocontinuous arterial spin labeling (ASL) MRI after ischemic stroke and assessed the association between CBF and early neurological outcome. We acquired ASL with 7 PLDs at 3.0 T in large vessel occlusion stroke patients at 24 h. We quantified CBF relative to the contralateral hemisphere (rCBF) and defined hyperperfusion as a ≥30% increase and hypoperfusion as a ≥40% decrease in rCBF. We included 44 patients (median age: 70 years, median NIHSS: 13, 40 treated with endovascular thrombectomy) of whom 37 were recanalized. Hyperperfusion in ischemic core occurred in recanalized but not in non-recanalized patients (65.8% vs 0%, p = 0.006). Hypoperfusion occurred only in the latter group (0% vs 85.7%, p < 0.001). In recanalized patients, hyperperfusion was also seen in salvaged penumbra (38.9%). Higher rCBF in ischemic core (aβ, -2.75 [95% CI: -4.11 to -1.40]) and salvaged penumbra (aβ, -5.62 [95% CI: -9.57 to -1.68]) was associated with lower NIHSS scores at 24 h. In conclusion, hyperperfusion frequently occurs in infarcted and salvaged brain tissue following successful recanalization and early neurological outcome is positively associated with the level of reperfusion.

Possible Contribution of the Aspiration Catheter in Preventing Post-stent Retriever Thrombectomy Subarachnoid Hemorrhage

PURPOSE

This study aimed to identify factors related to the incidence of post-thrombectomy subarachnoid hemorrhage (PTSAH).

METHODS

This retrospective, observational cohort study enrolled consecutive patients with acute ischemic stroke (AIS) due to the internal carotid artery (IC) top or middle cerebral artery (MCA) M1 or M2 segment occlusion who underwent single-pass stent retriever (SR) treatment between January 2015 and May 2022 at two acute care hospitals.

RESULTS

Of the 54 included patients, 10 were in the PTSAH group (18.5%). The occlusion sites were IC top (31.5%), M1 segment (48.1%), and M2 segment (20.4%). Aspiration catheters (ACs) were used in 32 (59.3%) patients; however, the combined technique (AC advancement at least to the most proximal marker of SR) was actually used in 26 (48.1%) patients because a ledge effect at the ophthalmic artery origin from the IC interfered with distal navigation of the ACs. The baseline patient characteristics did not differ between the groups. M2 segment occlusion in the PTSAH and non-PTSAH groups were 40.0% and 15.9%, respectively (p = 0.19). More ACs were used in the non-PTSAH group (65.9% vs. 30.0%, p = 0.07). Significantly fewer combined techniques were performed in the PTSAH group (10.0% vs. 56.8%, p = 0.01). In multivariate analysis adjusted by variables with M2 segment occlusion and the combined technique, the combined technique (odds ratio 0.098; 95% confidence interval, 0.011-0.887; p = 0.039) was identified as a significantly associated factor for PTSAH. There was one PTSAH case (1.9%) with symptom worsening.

CONCLUSION

The combined technique significantly influenced PTSAH occurrence as a preventive factor.

Effect of blood pressure on the prognosis of acute ischemic stroke patients caused by anterior circulation large vessel occlusion without recanalization

PURPOSE

To explore the effect of blood pressure on the prognosis of acute ischemic stroke patients caused by anterior circulation large vessel occlusion without recanalization.

METHODS

Acute ischemic stroke patients caused by anterior circulation large vessel occlusion without recanalization were retrospectively collected. All patients were divided into the functional independent group and non-functional independent group, death group and non-death group based on the 90-day mRS score. Logistic regression was applied to analyze the relationship between the highest systolic blood pressure, the average systolic blood pressure, the lowest systolic blood pressure, the highest diastolic blood pressure, the average diastolic blood pressure, the lowest diastolic blood pressure in the first 24 h after admission and the functional prognosis as well as the complications after 90 days. The independent impact factors selected from regression analysis were used to investigate the blood pressure with prognostic value by receiver operating characteristic curve (ROC).

RESULTS

A total of 70 patients were recruited in this study. Among them, 39 cases (55.71%) were male and 31 cases (44.29%) were female, with a mean age of 61.83 ± 15.24 years old. 15 cases (21.43%) had a favorable 90-day outcome, and the other 55 cases (78.57%) had a higher mRS Score. After a 90-day follow-up, univariate analysis showed that hypertension and hyperlipidemia, highest systolic blood pressure, mean systolic blood pressure and NIHSS score were statistically significant in two groups with or without functional independence, while the NIHSS score at admission, systolic blood pressure at admission, average systolic blood pressure, highest systolic blood pressure and diastolic blood pressure were statistically significant in patients with death outcomes (P < 0.05). Multivariate regression analysis suggested that the highest systolic blood pressure was statistically significant (P < 0.05), the further ROC curve results showed the cut-off value of the highest systolic blood pressure was 180.5 mmHg, with a sensitivity of 82.35% and a specificity of 81.13%. The highest Youden's index was 0.6348.

CONCLUSION

For acute ischemic stroke patients caused by anterior circulation large vessel occlusion without recanalization, the appropriate reduction of blood pressure within 24 h after admission may have a positive effect on the clinical prognosis. The 90-day mortality of acute ischemic stroke patients without revascularization was independently related to the highest systolic blood pressure. The risk of death was increased when the highest systolic blood pressure was greater than 180.5 mmHg.

Impact of Patency of the Carotid Terminus and Middle Cerebral Artery on Early Clinical Outcomes in Patients with Acute Internal Carotid Artery Occlusion and Mild Symptoms

INTRODUCTION

Both collateral flow via the internal carotid artery (ICA) terminus (ICT) and initial mild symptoms might be associated with favorable outcomes in patients with acute ICA occlusion (ICAO). This study aimed to address the association between early clinical outcomes and patency of the ICT and middle cerebral artery (MCA) in patients with acute ICAO with mild symptoms.

METHODS

Of 1,214 consecutive patients with acute ischemic stroke or transient ischemic attack due to large vessel occlusion, patients with ipsilateral ICAO and initial National Institutes of Health Stroke Scale (NIHSS) score ≤5 were retrospectively enrolled. We examined the associations between clinical factors including patency of the ICT and MCA and recurrence of stroke or early neurological deterioration (REND). Significant early neurological deterioration was defined as increment in NIHSS score ≥1 during hospital stay.

RESULTS

Thirteen of the 35 patients who were finally enrolled had REND (37%), and median modified Rankin scale (mRS) score at discharge was 1 (interquartile range, 0-4). Initial NIHSS score (4 vs. 1, p < 0.001) and rates of diabetes mellitus (61.5% vs. 13.6%, p = 0.007), intravenous thrombolysis (IVT) (30.9% vs. 0%, p = 0.014), and mechanical thrombectomy (MT) (23.1% vs. 0%, p = 0.044) were significantly higher in patients with REND rather than in those without. The rate of patent ICT and MCA was comparable between groups. Except for 1 patient who underwent MT promptly after IVT immediately after REND, 3 patients initially treated with IVT deteriorated after the procedure. One patient without patent ICT and MCA did not meet the indications for MT. In 2 other patients with patent ICT and MCA, MT was not initially performed, but was eventually performed because of REND due to thrombus migration, and both were discharged with an mRS score of 5.

CONCLUSION

The overall clinical outcomes of patients with acute ICAO with mild symptoms were not depending on the patency of the ICT and MCA, but initial treatment with IVT alone might risk unfavorable outcomes due to thrombus migration in patients with patent ICT and MCA.

Endovascular Therapy in Acute Isolated Posterior Cerebral Artery Occlusion : Systematic Review and Meta-analysis

PURPOSE

Patients with isolated posterior cerebral artery occlusion (iPCAO) represent up to 6% of all acute ischemic stroke patients. Acute revascularization therapies for these patients were not tested in randomized controlled trials. The aim of this study was to evaluate outcomes of iPCAO patients who undergo endovascular treatment (EVT).

METHODS

A systematic search of MEDLINE, Web of Science, CENTRAL, Scopus (inception-03/2022) was conducted for studies reporting 3‑month outcome, symptomatic intracranial hemorrhage (sICH) and/or successful recanalization in iPCAO patients who underwent EVT. Random effect meta-analyses for pooled proportions were calculated. Double-arm meta-analyses for comparison of outcomes of iPCAO patients treated with EVT with age-, sex- and NIHSS-matched iPCAO patients treated with best medical treatment only were performed.

RESULTS

Fifteen studies reporting a total of 461 iPCAO patients who underwent EVT were included. Excellent and favorable 3‑month outcome proportions were 36% (95% confidence interval, CI 20-51%) and 57% (95% CI 40-73%), respectively. The 3‑month mortality was 9% (95% CI 5-13), sICH occurred in 1% (95% CI 0-2%), successful recanalization was achieved in 79% (95% CI 71-86%). No significant differences in favorable and excellent 3‑month outcomes, 3‑month mortality and symptomatic intracerebral hemorrhage were found between the groups of patients who underwent EVT and the group of patients who received best medical treatment only.

CONCLUSION

These results support the feasibility and safety of EVT in iPCAO, but do not show an outcome benefit with EVT compared to best medical treatment. Randomized trials are needed to evaluate treatment benefit of EVT in these patients.

Arterial Glyceryl Trinitrate in Acute Ischemic Stroke after Thrombectomy for Neuroprotection (AGAIN): Rationale, design and protocol for a prospective randomized controlled trial

Background

Although endovascular recanalization therapy demonstrates robust clinical efficacy in acute ischemic stroke (AIS), not all victims of these cerebrovascular accidents can benefit from it and achieve a favorable prognosis after successful reperfusion. Therefore, alternative neuroprotective strategies are urgently needed for AIS patients after vessel recanalization. Nitric oxide (NO) levels are low after AIS and NO donor drugs may be neuroprotective against cerebral ischemia–reperfusion injury. Glyceryl trinitrate (GTN), often used in the clinic as a NO donor, may provide a novel neuroprotective strategy. This rationale, design, and protocol for a prospective pilot study plans to explore the preliminary safety, feasibility, and neuroprotective benefits of Arterial Glyceryl Trinitrate in Acute Ischemic Stroke after Thrombectomy for Neuroprotection (AGAIN).

Methods

AGAIN, a prospective RCT, is proposed for AIS patients after mechanical thrombectomy. Subjects will be randomly assigned in a 1:1 fashion (n = 40) to either the control group or the intervention group. Participants assigned to the intervention group will be administered 800 μg GTN in the catheter immediately after recanalization, whereas those in the control group will be administered the same volume of normal saline. All participants from either group will be given concurrent treatment with standard of care therapies in accordance with the current guidelines for stroke management. The primary outcome is safety [symptomatic intracranial hemorrhage (ICH), hypotension, neurological deterioration, ICH, fatal ICH, as well as headache, tachycardia, emesis, and seizures], whereas secondary outcomes included changes in poststroke functional outcomes, infarction volumes, and blood nitrate index detection.

Discussions

This study is a prospective randomized controlled trial to test the safety and efficacy of intra-arterial GTN in AIS patients after endovascular therapy. The results from this study will give insight for future GTN studies and new neuroprotective strategies for future AIS treatment strategies.

Trial registration number

ChiCTR2100045254. Registered on March 21, 2021.