What Is a Meaningful Difference When Using Infarct Volume as the Primary Outcome?: Results From the HERMES Database.

BACKGROUND: Ischemic stroke lesion volume at follow-up is an important surrogate outcome for acute stroke trials. We aimed to assess which differences in 48-hour lesion volume translate into meaningful clinical differences. METHODS: We used pooled data from 7 trials investigating the efficacy of endovascular treatment for anterior circulation large vessel occlusion in acute ischemic stroke. We assessed 48-hour lesion volume follow-up computed tomography or magnetic resonance imaging. The primary outcome was a good functional outcome, defined as modified Rankin Scale (mRS) scores of 0 to 2. We performed multivariable logistic regression to predict the probability of achieving mRS scores of 0 to 2 and determined the differences in 48-hour lesion volume that correspond to a change of 1%, 5%, and 10% in the adjusted probability of achieving mRS scores of 0 to 2. RESULTS: In total, 1665/1766 (94.2%) patients (median age, 68 [interquartile range, 57-76] years, 781 [46.9%] female) had information on follow-up ischemic lesion volume. Computed tomography was used for follow-up imaging in 83% of patients. The median 48-hour lesion volume was 41 (interquartile range, 14-120) mL. We observed a linear relationship between 48-hour lesion volume and mRS scores of 0 to 2 for adjusted probabilities between 65% and 20%/volumes <80 mL, although the curve sloped off for lower mRS scores of 0-2 probabilities/higher volumes. The median differences in 48-hour lesion volume associated with a 1%, 5%, and 10% increase in the probability of mRS scores of 0 to 2 for volumes <80 mL were 2 (interquartile range, 2-3), 10 (9-11), and 20 (18-23) mL, respectively. We found comparable associations when assessing computed tomography and magnetic resonance imaging separately. CONCLUSIONS: A difference of 2, 10, and 20 mL in 48-hour lesion volume, respectively, is associated with a 1%, 5%, and 10% absolute increase in the probability of achieving good functional outcome. These results can inform the design of future stroke trials that use 48-hour lesion volume as the primary outcome.

Intravenous Thrombolysis Before Endovascular Treatment in Posterior Circulation Occlusions: A MR CLEAN Registry Study.

BACKGROUND: The effectiveness of intravenous thrombolysis (IVT) before endovascular treatment (EVT) has been investigated in randomized trials and meta-analyses. These studies mainly concerned anterior circulation occlusions. We aimed to investigate clinical, technical, and safety outcomes of IVT before EVT in posterior circulation occlusions in a nationwide registry. METHODS: Patients were included from the MR CLEAN Registry (Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands), a nationwide, prospective, multicenter registry of patients with acute ischemic stroke due to a large intracranial vessel occlusion receiving EVT between 2014 and 2019. All patients with a posterior circulation occlusion were included. Primary outcome was a shift toward better functional outcome on the modified Rankin Scale at 90 days. Secondary outcomes were favorable functional outcome (modified Rankin Scale scores, 0-3), occurrence of symptomatic intracranial hemorrhages, successful reperfusion (extended Thrombolysis in Cerebral Ischemia ≥2B), first-attempt successful reperfusion, and mortality at 90 days. Regression analyses with adjustments based on univariable analyses and literature were applied. RESULTS: A total of 248 patients were included, who received either IVT (n=125) or no IVT (n=123) before EVT. Results show no differences in a shift on the modified Rankin Scale (adjusted common odds ratio, 1.04 [95% CI, 0.61-1.76]). Although symptomatic intracranial hemorrhages occurred more often in the IVT group (4.8% versus 2.4%), regression analysis did not show a significant difference (adjusted odds ratio, 1.65 [95% CI, 0.33-8.35]). Successful reperfusion, favorable functional outcome, first-attempt successful reperfusion, and mortality did not differ between patients treated with and without IVT. CONCLUSIONS: We found no significant differences in clinical, technical, and safety outcomes between patients with a large vessel occlusion in the posterior circulation treated with or without IVT before EVT. Our results are in line with the literature on the anterior circulation.

Endovascular Thrombectomy Alone for Large Vessel Occlusion: A Cost-Effectiveness Evaluation Based on Meta-Analyses.

BACKGROUND: The benefit of intravenous thrombolysis with alteplase before endovascular thrombectomy (EVT) for acute ischemic stroke due to large vessel occlusion remains debated. In this study, we analyzed the cost-effectiveness of EVT alone versus intravenous alteplase before EVT in patients directly admitted to EVT-capable stroke centers from the Dutch health care payer perspective. METHODS: A decision analysis was performed using a Markov model with 15-year simulated follow-up to estimate total costs, quality-adjusted life years, and an incremental cost-effectiveness ratio of intravenous alteplase before EVT compared with EVT alone. A hypothetical cohort of 10 000 patients with large vessel occlusion aged 70 years was run in Monte Carlo simulation. Functional outcome of each treatment was derived from pooled results of 6 randomized controlled trials (RCTs). Uncertainty was assessed by probabilistic analyses, scenario analyses, and 1-way sensitivity analyses. RESULTS: Using functional outcomes obtained from 6 RCTs (intention-to-treat population), intravenous alteplase before EVT resulted in 0.05 quality-adjusted life years gained at an additional $2817 compared with EVT alone, resulting in the incremental cost-effectiveness ratio of $62 287. Probabilistic analyses showed that intravenous alteplase before EVT had a probability of 45% and 54%, respectively, of being cost-effective at the $52 500 and $84 000 thresholds. Restricting functional outcomes from our post hoc modified as-treated analysis of 6 RCTs (scenario 1), European RCTs (scenario 2), or a Dutch RCT (scenario 3), intravenous alteplase before EVT was cost-effective in 64%, 81%, and 50% of simulations at the $52 500 threshold, and 79%, 91%, and 67% of simulations at the $84 000 threshold. CONCLUSIONS: Intravenous alteplase before EVT was not cost-effective in patients with large vessel occlusion in the Netherlands at the $52 500 threshold but possibly cost-effective at the $84 000 threshold. Variable functional outcomes at 3 months based on different trial populations affected the cost-effectiveness of intravenous alteplase before EVT.

RABENOSYN separation-of-function mutations uncouple endosomal recycling from lysosomal degradation, causing a distinct Mendelian disorder.

Rabenosyn (RBSN) is a conserved endosomal protein necessary for regulating internalized cargo. Here, we present clinical, genetic, cellular and biochemical evidence that two distinct RBSN missense variants are responsible for a novel Mendelian disorder consisting of progressive muscle weakness, facial dysmorphisms, ophthalmoplegia and intellectual disability. Using exome sequencing, we identified recessively acting germline alleles p.Arg180Gly and p.Gly183Arg, which are both situated in the FYVE domain of RBSN. We find that these variants abrogate binding to its cognate substrate phosphatidylinositol 3-phosphate (PI3P) and thus prevent its translocation to early endosomes. Although the endosomal recycling pathway was unaltered, mutant p.Gly183Arg patient fibroblasts show accumulation of cargo tagged for lysosomal degradation. Our results suggest that these variants are separation-of-function alleles, which cause a delay in endosomal maturation without affecting cargo recycling. We conclude that distinct germline mutations in RBSN cause non-overlapping phenotypes with specific and discrete endolysosomal cellular defects.

Value of intravenous thrombolysis in endovascular treatment for large-vessel anterior circulation stroke: individual participant data meta-analysis of six randomised trials.

BACKGROUND: Intravenous thrombolysis is recommended before endovascular treatment, but its value has been questioned in patients who are admitted directly to centres capable of endovascular treatment. Existing randomised controlled trials have indicated non-inferiority of endovascular treatment alone or have been statistically inconclusive. We formed the Improving Reperfusion Strategies in Acute Ischaemic Stroke collaboration to assess non-inferiority of endovascular treatment alone versus intravenous thrombolysis plus endovascular treatment. METHODS: We conducted a systematic review and individual participant data meta-analysis to establish non-inferiority of endovascular treatment alone versus intravenous thrombolysis plus endovascular treatment. We searched PubMed and MEDLINE with the terms "stroke", "endovascular treatment", "intravenous thrombolysis", and synonyms for articles published from database inception to March 9, 2023. We included randomised controlled trials on the topic of interest, without language restrictions. Authors of the identified trials agreed to take part, and individual participant data were provided by the principal investigators of the respective trials and collated centrally by the collaborators. Our primary outcome was the 90-day modified Rankin Scale (mRS) score. Non-inferiority of endovascular treatment alone was assessed using a lower boundary of 0·82 for the 95% CI around the adjusted common odds ratio (acOR) for shift towards improved outcome (analogous to 5% absolute difference in functional independence) with ordinal regression. We used mixed-effects models for all analyses. This study is registered with PROSPERO, CRD42023411986. FINDINGS: We identified 1081 studies, and six studies (n=2313; 1153 participants randomly assigned to receive endovascular treatment alone and 1160 randomly assigned to receive intravenous thrombolysis and endovascular treatment) were eligible for analysis. The risk of bias of the included studies was low to moderate. Variability between studies was small, and mainly related to the choice and dose of the thrombolytic drug and country of execution. The median mRS score at 90 days was 3 (IQR 1-5) for participants who received endovascular treatment alone and 2 (1-4) for participants who received intravenous thrombolysis plus endovascular treatment (acOR 0·89, 95% CI 0·76-1·04). Any intracranial haemorrhage (0·82, 0·68-0·99) occurred less frequently with endovascular treatment alone than with intravenous thrombolysis plus endovascular treatment. Symptomatic intracranial haemorrhage and mortality rates did not differ significantly. INTERPRETATION: We did not establish non-inferiority of endovascular treatment alone compared with intravenous thrombolysis plus endovascular treatment in patients presenting directly at endovascular treatment centres. Further research could focus on cost-effectiveness analysis and on individualised decisions when patient characteristics, medication shortages, or delays are expected to offset a potential benefit of administering intravenous thrombolysis before endovascular treatment. FUNDING: Stryker and Amsterdam University Medical Centers, University of Amsterdam.

Endovascular Therapy for Stroke Due to Basilar-Artery Occlusion.

BACKGROUND: The effectiveness of endovascular therapy in patients with stroke caused by basilar-artery occlusion has not been well studied. METHODS: We randomly assigned patients within 6 hours after the estimated time of onset of a stroke due to basilar-artery occlusion, in a 1:1 ratio, to receive endovascular therapy or standard medical care. The primary outcome was a favorable functional outcome, defined as a score of 0 to 3 on the modified Rankin scale (range, 0 to 6, with 0 indicating no disability, 3 indicating moderate disability, and 6 indicating death) at 90 days. The primary safety outcomes were symptomatic intracranial hemorrhage within 3 days after the initiation of treatment and mortality at 90 days. RESULTS: A total of 300 patients were enrolled (154 in the endovascular therapy group and 146 in the medical care group). Intravenous thrombolysis was used in 78.6% of the patients in the endovascular group and in 79.5% of those in the medical group. Endovascular treatment was initiated at a median of 4.4 hours after stroke onset. A favorable functional outcome occurred in 68 of 154 patients (44.2%) in the endovascular group and 55 of 146 patients (37.7%) in the medical care group (risk ratio, 1.18; 95% confidence interval [CI], 0.92 to 1.50). Symptomatic intracranial hemorrhage occurred in 4.5% of the patients after endovascular therapy and in 0.7% of those after medical therapy (risk ratio, 6.9; 95% CI, 0.9 to 53.0); mortality at 90 days was 38.3% and 43.2%, respectively (risk ratio, 0.87; 95% CI, 0.68 to 1.12). CONCLUSIONS: Among patients with stroke from basilar-artery occlusion, endovascular therapy and medical therapy did not differ significantly with respect to a favorable functional outcome, but, as reflected by the wide confidence interval for the primary outcome, the results of this trial may not exclude a substantial benefit of endovascular therapy. Larger trials are needed to determine the efficacy and safety of endovascular therapy for basilar-artery occlusion. (Funded by the Dutch Heart Foundation and others; BASICS ClinicalTrials.gov number, NCT01717755; Netherlands Trial Register number, NL2500.).

Costs and health effects of CT perfusion-based selection for endovascular thrombectomy within 6 hours of stroke onset: a model-based health economic evaluation.

BACKGROUND: Although CT perfusion (CTP) is often incorporated in acute stroke workflows, it remains largely unclear what the associated costs and health implications are in the long run of CTP-based patient selection for endovascular treatment (EVT) in patients presenting within 6 hours after symptom onset with a large vessel occlusion. METHODS: Patients with a large vessel occlusion were included from a Dutch nationwide cohort (n=703) if CTP imaging was performed before EVT within 6 hours after stroke onset. Simulated cost and health effects during 5 and 10 years follow-up were compared between CTP based patient selection for EVT and providing EVT to all patients. Outcome measures were the net monetary benefit at a willingness-to-pay of €80 000 per quality-adjusted life year, incremental cost-effectiveness ratio), difference in costs from a healthcare payer perspective (ΔCosts) and quality-adjusted life years (ΔQALY) per 1000 patients for 1000 model iterations as outcomes. RESULTS: Compared with treating all patients, CTP-based selection for EVT at the optimised ischaemic core volume (ICV≥110 mL) or core-penumbra mismatch ratio (MMR≤1.4) thresholds resulted in losses of health (median ΔQALYs for ICV≥110 mL: -3.3 (IQR: -5.9 to -1.1), for MMR≤1.4: 0.0 (IQR: -1.3 to 0.0)) with median ΔCosts for ICV≥110 mL of -€348 966 (IQR: -€712 406 to -€51 158) and for MMR≤1.4 of €266 513 (IQR: €229 403 to €380 110)) per 1000 patients. Sensitivity analyses did not yield any scenarios for CTP-based selection of patients for EVT that were cost-effective for improving health, including patients aged ≥80 years CONCLUSION: In EVT-eligible patients presenting within 6 hours after symptom onset, excluding patients based on CTP parameters was not cost-effective and could potentially harm patients.

Standardizing the estimation of ischemic regions can harmonize CT perfusion stroke imaging.

OBJECTIVES: We aimed to evaluate the real-world variation in CT perfusion (CTP) imaging protocols among stroke centers and to explore the potential for standardizing vendor software to harmonize CTP images. METHODS: Stroke centers participating in a nationwide multicenter healthcare evaluation were requested to share their CTP scan and processing protocol. The impact of these protocols on CTP imaging was assessed by analyzing data from an anthropomorphic phantom with center-specific vendor software with default settings from one of three vendors (A-C): IntelliSpace Portal, syngoVIA, and Vitrea. Additionally, standardized infarct maps were obtained using a logistic model. RESULTS: Eighteen scan protocols were studied, all varying in acquisition settings. Of these protocols, seven, eight, and three were analyzed with center-specific vendor software A, B, and C respectively. The perfusion maps were visually dissimilar between the vendor software but were relatively unaffected by the acquisition settings. The median error [interquartile range] of the infarct core volumes (mL) estimated by the vendor software was - 2.5 [6.5] (A)/ - 18.2 [1.2] (B)/ - 8.0 [1.4] (C) when compared to the ground truth of the phantom (where a positive error indicates overestimation). Taken together, the median error [interquartile range] of the infarct core volumes (mL) was - 8.2 [14.6] before standardization and - 3.1 [2.5] after standardization. CONCLUSIONS: CTP imaging protocols varied substantially across different stroke centers, with the perfusion software being the primary source of differences in CTP images. Standardizing the estimation of ischemic regions harmonized these CTP images to a degree. CLINICAL RELEVANCE STATEMENT: The center that a stroke patient is admitted to can influence the patient's diagnosis extensively. Standardizing vendor software for CT perfusion imaging can improve the consistency and accuracy of results, enabling a more reliable diagnosis and treatment decision. KEY POINTS: • CT perfusion imaging is widely used for stroke evaluation, but variation in the acquisition and processing protocols between centers could cause varying patient diagnoses. • Variation in CT perfusion imaging mainly arises from differences in vendor software rather than acquisition settings, but these differences can be reconciled by standardizing the estimation of ischemic regions. • Standardizing the estimation of ischemic regions can improve CT perfusion imaging for stroke evaluation by facilitating reliable evaluations independent of the admission center.

Deep learning-based white matter lesion volume on CT is associated with outcome after acute ischemic stroke.

BACKGROUND: Intravenous thrombolysis (IVT) before endovascular treatment (EVT) for acute ischemic stroke might induce intracerebral hemorrhages which could negatively affect patient outcomes. Measuring white matter lesions size using deep learning (DL-WML) might help safely guide IVT administration. We aimed to develop, validate, and evaluate a DL-WML volume on CT compared to the Fazekas scale (WML-Faz) as a risk factor and IVT effect modifier in patients receiving EVT directly after IVT. METHODS: We developed a deep-learning model for WML segmentation on CT and validated with internal and external test sets. In a post hoc analysis of the MR CLEAN No-IV trial, we associated DL-WML volume and WML-Faz with symptomatic-intracerebral hemorrhage (sICH) and 90-day functional outcome according to the modified Rankin Scale (mRS). We used multiplicative interaction terms between WML measures and IVT administration to evaluate IVT treatment effect modification. Regression models were used to report unadjusted and adjusted common odds ratios (cOR/acOR). RESULTS: In total, 516 patients from the MR CLEAN No-IV trial (male/female, 291/225; age median, 71 [IQR, 62-79]) were analyzed. Both DL-WML volume and WML-Faz are associated with sICH (DL-WML volume acOR, 1.78 [95%CI, 1.17; 2.70]; WML-Faz acOR, 1.53 95%CI [1.02; 2.31]) and mRS (DL-WML volume acOR, 0.70 [95%CI, 0.55; 0.87], WML-Faz acOR, 0.73 [95%CI 0.60; 0.88]). Only in the unadjusted IVT effect modification analysis WML-Faz was associated with more sICH if IVT was given (p = 0.046). Neither WML measure was associated with worse mRS if IVT was given. CONCLUSION: DL-WML volume and WML-Faz had a similar relationship with functional outcome and sICH. Although more sICH might occur in patients with more severe WML-Faz receiving IVT, no worse functional outcome was observed. CLINICAL RELEVANCE STATEMENT: White matter lesion severity on baseline CT in acute ischemic stroke patients has a similar predictive value if measured with deep learning or the Fazekas scale. Safe administration of intravenous thrombolysis using white matter lesion severity should be further studied. KEY POINTS: White matter damage is a predisposing risk factor for intracranial hemorrhage in patients with acute ischemic stroke but remains difficult to measure on CT. White matter lesion volume on CT measured with deep learning had a similar association with symptomatic intracerebral hemorrhages and worse functional outcome as the Fazekas scale. A patient-level meta-analysis is required to study the benefit of white matter lesion severity-based selection for intravenous thrombolysis before endovascular treatment.

Cost-effectiveness of CT perfusion for the detection of large vessel occlusion acute ischemic stroke followed by endovascular treatment: a model-based health economic evaluation study.

OBJECTIVES: CT perfusion (CTP) has been suggested to increase the rate of large vessel occlusion (LVO) detection in patients suspected of acute ischemic stroke (AIS) if used in addition to a standard diagnostic imaging regime of CT angiography (CTA) and non-contrast CT (NCCT). The aim of this study was to estimate the costs and health effects of additional CTP for endovascular treatment (EVT)-eligible occlusion detection using model-based analyses. METHODS: In this Dutch, nationwide retrospective cohort study with model-based health economic evaluation, data from 701 EVT-treated patients with available CTP results were included (January 2018-March 2022; trialregister.nl:NL7974). We compared a cohort undergoing NCCT, CTA, and CTP (NCCT + CTA + CTP) with a generated counterfactual where NCCT and CTA (NCCT + CTA) was used for LVO detection. The NCCT + CTA strategy was simulated using diagnostic accuracy values and EVT effects from the literature. A Markov model was used to simulate 10-year follow-up. We adopted a healthcare payer perspective for costs in euros and health gains in quality-adjusted life years (QALYs). The primary outcome was the net monetary benefit (NMB) at a willingness to pay of €80,000; secondary outcomes were the difference between LVO detection strategies in QALYs (ΔQALY) and costs (ΔCosts) per LVO patient. RESULTS: We included 701 patients (median age: 72, IQR: [62-81]) years). Per LVO patient, CTP-based occlusion detection resulted in cost savings (ΔCosts median: € - 2671, IQR: [€ - 4721; € - 731]), a health gain (ΔQALY median: 0.073, IQR: [0.044; 0.104]), and a positive NMB (median: €8436, IQR: [5565; 11,876]) per LVO patient. CONCLUSION: CTP-based screening of suspected stroke patients for an endovascular treatment eligible large vessel occlusion was cost-effective. CLINICAL RELEVANCE STATEMENT: Although CTP-based patient selection for endovascular treatment has been recently suggested to result in worse patient outcomes after ischemic stroke, an alternative CTP-based screening for endovascular treatable occlusions is cost-effective. KEY POINTS: • Using CT perfusion to detect an endovascular treatment-eligible occlusions resulted in a health gain and cost savings during 10 years of follow-up. • Depending on the screening costs related to the number of patients needed to image with CT perfusion, cost savings could be considerable (median: € - 3857, IQR: [€ - 5907; € - 1916] per patient). • As the gain in quality adjusted life years was most affected by the sensitivity of CT perfusion-based occlusion detection, additional studies for the diagnostic accuracy of CT perfusion for occlusion detection are required.

Deep learning for efficient reconstruction of highly accelerated 3D FLAIR MRI in neurological deficits.

OBJECTIVE: To compare compressed sensing (CS) and the Cascades of Independently Recurrent Inference Machines (CIRIM) with respect to image quality and reconstruction times when 12-fold accelerated scans of patients with neurological deficits are reconstructed. MATERIALS AND METHODS: Twelve-fold accelerated 3D T2-FLAIR images were obtained from a cohort of 62 patients with neurological deficits on 3 T MRI. Images were reconstructed offline via CS and the CIRIM. Image quality was assessed in a blinded and randomized manner by two experienced interventional neuroradiologists and one experienced pediatric neuroradiologist on imaging artifacts, perceived spatial resolution (sharpness), anatomic conspicuity, diagnostic confidence, and contrast. The methods were also compared in terms of self-referenced quality metrics, image resolution, patient groups and reconstruction time. In ten scans, the contrast ratio (CR) was determined between lesions and white matter. The effect of acceleration factor was assessed in a publicly available fully sampled dataset, since ground truth data are not available in prospectively accelerated clinical scans. Specifically, 451 FLAIR scans, including scans with white matter lesions, were adopted from the FastMRI database to evaluate structural similarity (SSIM) and the CR of lesions and white matter on ranging acceleration factors from four-fold up to 12-fold. RESULTS: Interventional neuroradiologists significantly preferred the CIRIM for imaging artifacts, anatomic conspicuity, and contrast. One rater significantly preferred the CIRIM in terms of sharpness and diagnostic confidence. The pediatric neuroradiologist preferred CS for imaging artifacts and sharpness. Compared to CS, the CIRIM reconstructions significantly improved in terms of imaging artifacts and anatomic conspicuity (p < 0.01) for higher resolution scans while yielding a 28% higher SNR (p = 0.001) and a 5.8% lower CR (p = 0.04). There were no differences between patient groups. Additionally, CIRIM was five times faster than CS was. An increasing acceleration factor did not lead to changes in CR (p = 0.92), but led to lower SSIM (p = 0.002). DISCUSSION: Patients with neurological deficits can undergo MRI at a range of moderate to high acceleration. DL reconstruction outperforms CS in terms of image resolution, efficient denoising with a modest reduction in contrast and reduced reconstruction times.

Symptomatic Intracranial Hemorrhage After Endovascular Stroke Treatment: External Validation of Prediction Models.

BACKGROUND: Symptomatic intracranial hemorrhage (sICH) is a severe complication of reperfusion therapy for ischemic stroke. Multiple models have been developed to predict sICH or intracranial hemorrhage (ICH) after reperfusion therapy. We provide an overview of published models and validate their ability to predict sICH in patients treated with endovascular treatment in daily clinical practice. METHODS: We conducted a systematic search to identify models either developed or validated to predict sICH or ICH after reperfusion therapy (intravenous thrombolysis and/or endovascular treatment) for ischemic stroke. Models were externally validated in the MR CLEAN Registry (n=3180; Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands). The primary outcome was sICH according to the Heidelberg Bleeding Classification. Model performance was evaluated with discrimination (c-statistic, ideally 1; a c-statistic below 0.7 is considered poor in discrimination) and calibration (slope, ideally 1, and intercept, ideally 0). RESULTS: We included 39 studies describing 40 models. The most frequently used predictors were baseline National Institutes of Health Stroke Scale (NIHSS; n=35), age (n=22), and glucose level (n=22). In the MR CLEAN Registry, sICH occurred in 188/3180 (5.9%) patients. Discrimination ranged from 0.51 (SPAN-100 [Stroke Prognostication Using Age and National Institutes of Health Stroke Scale]) to 0.61 (SITS-SICH [Safe Implementation of Treatments in Stroke Symptomatic Intracerebral Hemorrhage] and STARTING-SICH [STARTING Symptomatic Intracerebral Hemorrhage]). Best calibrated models were IST-3 (intercept, -0.15 [95% CI, -0.01 to -0.31]; slope, 0.80 [95% CI, 0.50-1.09]), SITS-SICH (intercept, 0.15 [95% CI, -0.01 to 0.30]; slope, 0.62 [95% CI, 0.38-0.87]), and STARTING-SICH (intercept, -0.03 [95% CI, -0.19 to 0.12]; slope, 0.56 [95% CI, 0.35-0.76]). CONCLUSIONS: The investigated models to predict sICH or ICH discriminate poorly between patients with a low and high risk of sICH after endovascular treatment in daily clinical practice and are, therefore, not clinically useful for this patient population.

Prognostic Value of Thrombus Volume and Interaction With First-Line Endovascular Treatment Device Choice.

BACKGROUND: A larger thrombus in patients with acute ischemic stroke might result in more complex endovascular treatment procedures, resulting in poorer patient outcomes. Current evidence on thrombus volume and length related to procedural and functional outcomes remains contradicting. This study aimed to assess the prognostic value of thrombus volume and thrombus length and whether this relationship differs between first-line stent retrievers and aspiration devices for endovascular treatment. METHODS: In this multicenter retrospective cohort study, 670 of 3279 patients from the MR CLEAN Registry (Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands) for endovascularly treated large vessel occlusions were included. Thrombus volume (0.1 mL) and length (0.1 mm) based on manual segmentations and measurements were related to reperfusion grade (expanded Treatment in Cerebral Infarction score) after endovascular treatment, the number of retrieval attempts, symptomatic intracranial hemorrhage, and a shift for functional outcome at 90 days measured with the reverted ordinal modified Rankin Scale (odds ratio >1 implies a favorable outcome). Univariable and multivariable linear and logistic regression were used to report common odds ratios (cORs)/adjusted cOR and regression coefficients (B/aB) with 95% CIs. Furthermore, a multiplicative interaction term was used to analyze the relationship between first-line device choice, stent retrievers versus aspiration device, thrombus volume, and outcomes. RESULTS: Thrombus volume was associated with functional outcome (adjusted cOR, 0.83 [95% CI, 0.71-0.97]) and number of retrieval attempts (aB, 0.16 [95% CI, 0.16-0.28]) but not with the other outcome measures. Thrombus length was only associated with functional independence (adjusted cOR, 0.45 [95% CI, 0.24-0.85]). Patients with more voluminous thrombi had worse functional outcomes if endovascular treatment was based on first-line stent retrievers (interaction cOR, 0.67 [95% CI, 0.50-0.89]; P=0.005; adjusted cOR, 0.74 [95% CI, 0.55-1.0]; P=0.04). CONCLUSIONS: In this study, patients with a more voluminous thrombus required more endovascular thrombus retrieval attempts and had a worse functional outcome. Patients with a lengthier thrombus were less likely to achieve functional independence at 90 days. For more voluminous thrombi, first-line stent retrieval compared with first-line aspiration might be associated with worse functional outcome.

Development and validation of a prediction model for failure of the transfemoral approach of endovascular treatment for large vessel occlusion acute ischemic stroke.

INTRODUCTION: Extracranial vascular characteristics determine the accessibility of the large vessel intracranial occlusion for endovascular treatment (EVT) in acute ischemic stroke. We developed and validated a prediction model for failure of the transfemoral approach to aid clinical decision making regarding EVT. METHODS: A prediction model was developed from data of patients included in the Dutch multicenter MR CLEAN Registry (March 18th 2014 until June 15th 2016) with penalized logistic regression. Predictor variables were available prior to the EVT procedure and included age, hypertension and extracranial vascular characteristics assessed on baseline CTA. The prediction model was internally validated, temporally validated within a second MR CLEAN Registry cohort (June 15th 2016 until November 1st 2017) and updated by re-estimating the coefficients using the combined cohort. RESULTS: Failure of the transfemoral approach occurred in 7% of patients, in both cohorts (derivation cohort: n=887, median age 71 years, interquartile range [IQR] 60-80, 52% men; validation cohort: n=1111, median age 73 years, IQR 62-81, 51% men). The prediction model had a c-statistic of 0.81 (95%CI: 0.76-0.86) in the derivation cohort, 0.69 (95%CI: 0.62-0.75) at temporal validation, and 0.75 (95%CI: 0.71-0.79) in the final prediction model, with the following penalized ß-coefficients for predictors age (per decade): 0.26, hypertension: -0.16, severe aortic arch elongation: 1.45, bovine aortic arch: 0.44, elongation of the supra-aortic arteries: 0.72, cervical ICA elongation: 0.44, and high-grade stenosis of the cervical ICA: 0.78. CONCLUSION: Our prediction model showed good performance for prediction of failure to reach the intracranial occlusion by the transfemoral approach.

Association between computed tomography perfusion and the effect of intravenous alteplase prior to endovascular treatment in acute ischemic stroke.

PURPOSE: Intravenous alteplase (IVT) prior to endovascular treatment (EVT) is neither superior nor noninferior to EVT alone in acute ischemic stroke patients. We aim to assess whether the effect of IVT prior to EVT differs according to CT perfusion (CTP)-based imaging parameters. METHODS: In this retrospective post hoc analysis, we included patients from the MR CLEAN-NO IV with available CTP data. CTP data were processed using syngo.via (version VB40). We performed multivariable logistic regression to obtain the effect size estimates (adjusted common odds ratio a[c]OR) on 90-day functional outcome (modified Rankin Scale [mRS]) and functional independence (mRS 0-2) for CTP parameters with two-way multiplicative interaction terms between IVT administration and the studied parameters. RESULTS: In 227 patients, median CTP-estimated core volume was 13 (IQR 5-35) mL. The treatment effect of IVT prior to EVT on outcome was not altered by CTP-estimated ischemic core volume, penumbral volume, mismatch ratio, and presence of a target mismatch profile. None of the CTP parameters was significantly associated with functional outcome after adjusting for confounders. CONCLUSION: In directly admitted patients with limited CTP-estimated ischemic core volumes who presented within 4.5 h after symptom onset, CTP parameters did not statistically significantly alter the treatment effect of IVT prior to EVT. Further studies are needed to confirm these results in patients with larger core volumes and more unfavorable baseline perfusion profiles on CTP imaging.

Infarct volume after ischemic stroke as a mediator of the effect of endovascular thrombectomy on early postprocedural neurologic deficit.

OBJECTIVES: The beneficial effect of endovascular thrombectomy (EVT) on clinical outcome is assumed to be caused by reduced follow-up infarct volume (FIV), which could serve as an early imaging endpoint. However, the effect of EVT on the modified Rankin Scale (mRS) was poorly explained by FIV. NIHSS at 5-7 days could be a more specific measure of the effect of reperfusion therapy, as opposed to the mRS at 3 months. Therefore, we aimed to assess to what extent the effect of EVT on NIHSS is explained by FIV. MATERIALS AND METHODS: We used data from the MR CLEAN (Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands; n = 500) trial to evaluate the mediating role of FIV within 1 week in the relationship between EVT and baseline adjusted NIHSS at 5-7 days. RESULTS: Larger FIVs were associated with higher NIHSS after treatment (adjusted beta-coefficient (aß) 0.47;95%CI 0.39-0.55). EVT was associated with smaller FIVs (ß -0.35;95%CI-0.64 to -0.06) and lower NIHSS (ß -0.63;95%CI-0.90 to -0.35). After adjustment for FIV, the effect of EVT on NIHSS decreased (aß -0.47;95%CI-0.72 to -0.23), indicating that effect of EVT on neurologic deficit is partially mediated by FIV. Reduction of FIV explained 34% (95%CI;5%-93%) of the effect of EVT on the NIHSS at 5-7 days. CONCLUSIONS: Larger FIV was significantly associated with larger neurological deficits after treatment. Reduced infarct volume after EVT explains one third of treatment benefit in terms of neurological deficit. This suggests that FIV is of interest as an imaging biomarker of stroke treatment effect.

Budget impact of endovascular treatment for acute ischaemic stroke patients in the Netherlands for 2015-2021.

INTRODUCTION: Endovascular treatment (EVT) has been proven to be both effective and cost-effective for patients with acute ischaemic stroke. We investigated the budget impact of large-scale implementation of EVT for acute ischaemic stroke patients in the Netherlands for 2015-2021. METHODS: An analysis was performed from a healthcare perspective as a preplanned substudy of the Multicenter Randomized Clinical trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands (MR CLEAN). Estimated yearly costs during follow-up after stroke for patients who had or had not been treated with EVT as add-on to usual care were linked to numbers of new patients retrieved from 2 Dutch registries of EVT that started after the last inclusion in MR CLEAN (2014). Aggregated costs and costs per care sector were calculated based on prevalence using a population dynamic tool. RESULTS: From 2015, the yearly number of new acute ischaemic stroke patients receiving EVT increased almost threefold, from 812 in 2015 to 2,370 in 2021. The introduction of EVT plus usual care resulted in estimated net annual savings that increased from €â€¯2.9 million in 2015 to €â€¯58 million in 2021. CONCLUSION: Offering EVT as add-on to usual care for acute ischaemic stroke patients was increasingly cost saving from a national healthcare perspective but affected distinct healthcare sectors differently.

Cardiac output, cerebral blood flow and cognition in patients with severe aortic valve stenosis undergoing transcatheter aortic valve implantation: design and rationale of the CAPITA study.

BACKGROUND: Approximately one-third of patients with symptomatic severe aortic valve stenosis who are scheduled for transcatheter aortic valve implantation (TAVI) have some degree of cognitive impairment. TAVI may have negative cognitive effects due to periprocedural micro-emboli inducing cerebral infarction. On the contrary, TAVI may also have positive cognitive effects due to increases in cardiac output and cerebral blood flow (CBF). However, studies that systematically assess these effects are scarce. Therefore, the main aim of this study is to assess cerebral and cognitive outcomes in patients with severe aortic valve stenosis undergoing TAVI. STUDY DESIGN: In the prospective CAPITA (CArdiac OutPut, Cerebral Blood Flow and Cognition In Patients With Severe Aortic Valve Stenosis Undergoing Transcatheter Aortic Valve Implantation) study, cerebral and cognitive outcomes are assessed in patients undergoing TAVI. One day before and 3 months after TAVI, patients will undergo echocardiography (cardiac output, valve function), brain magnetic resonance imaging (CBF, structural lesions) and extensive neuropsychological assessment. To assess longer-term effects of TAVI, patients will again undergo echocardiography and neuropsychological assessment 1 year after the procedure. The co-primary outcome measures are change in CBF (in ml/100 g per min) and change in global cognitive functioning (Z-score) between baseline and 3­month follow-up. Secondary objectives include change in cardiac output, white matter hyperintensities and other structural brain lesions. (ClinicalTrials.gov identifier NCT05481008) CONCLUSION : The CAPITA study is the first study designed to systematically assess positive and negative cerebral and cognitive outcomes after TAVI. We hypothesise that TAVI improves cardiac output, CBF and cognitive functioning.

Endovascular Thrombectomy in Young Patients With Stroke: A MR CLEAN Registry Study.

BACKGROUND AND PURPOSE: Acute ischemic stroke due to large vessel occlusion is uncommon in young adults. We assessed stroke cause in young patients and compared their outcomes after endovascular thrombectomy with older patients. METHODS: We used data (March 2014 until November 2017) of patients with an anterior circulation large vessel occlusion stroke from the MR CLEAN (Multicenter Randomized Controlled Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands) Registry, a nationwide, prospective study on endovascular thrombectomy in the Netherlands. We compared young patients (18-49 years) with older patients (≥50 years). Outcomes included modified Rankin Scale score after 90 days (both shift and dichotomized analyses), expanded Thrombolysis in Cerebral Infarction score, and symptomatic intracranial hemorrhage. Analyses were adjusted for confounding. RESULTS: We included 3256 patients, 310 (10%) were 18 to 49 years old. Young patients had lower median National Institutes of Health Stroke Scale scores (14 versus 16, P<0.001) and less cardiovascular comorbidities than older patients. Stroke etiologies in young patients included carotid dissection (16%), cardio-embolism (15%), large artery atherosclerosis (10%), and embolic stroke of undetermined source (31%). Clinical outcome was better in young than older patients (acOR for modified Rankin Scale shift: 1.8 [95% CI, 1.5-2.2]; functional independence [modified Rankin Scale score 0-2] 61 versus 39% [adjusted odds ratio, 2.1 [95% CI, 1.6-2.8]); mortality 7% versus 32%, adjusted odds ratio, 0.2 [95% CI, 0.1-0.3]). Symptomatic intracranial hemorrhage occurred less frequently in young patients (3% versus 6%, adjusted odds ratio, 0.5 [95% CI, 0.2-1.00]). Successful reperfusion (expanded Thrombolysis in Cerebral Infarction Score 2b-3) did not differ between groups. Onset to reperfusion time was shorter in young patients (253 versus 255 minutes, adjusted B in minutes 12.4 [95% CI, 2.4-22.5]). CONCLUSIONS: Ten percent of patients with acute ischemic stroke undergoing endovascular thrombectomy were younger than 50. Cardioembolism and carotid dissection were common underlying causes in young patients. In one-third of cases, no cause was identified, indicating the need for more research on stroke cause in young patients. Young patients had better prognosis and lower risk of symptomatic intracranial hemorrhage than older patients.

Thrombectomy With and Without Computed Tomography Perfusion Imaging in the Early Time Window: A Pooled Analysis of Patient-Level Data.

BACKGROUND: The optimal imaging paradigm for endovascular thrombectomy (EVT) patient selection in early time window (0-6 hours) treated acute ischemic stroke patients remains uncertain. We aimed to compare post-EVT outcomes between patients who underwent prerandomization basic (noncontrast computed tomography [CT], CT angiography only) versus additional advanced imaging (computed tomography perfusion [CTP] imaging) and to determine the association of performance of prerandomization CTP imaging with clinical outcomes. METHODS: The HERMES collaboration (Highly Effective Reperfusion Evaluated in Multiple Endovascular Stroke Trials) pooled patient-level data from randomized controlled trials comparing EVT with usual care for acute ischemic stroke due to anterior circulation large vessel occlusion. Good functional outcome, defined as modified Rankin Scale score 0 to 2 at 90 days, was compared between randomized patients with and without CTP baseline imaging. Univariable and multivariable binary logistic regression analysis was performed to determine the association of baseline CTP imaging and good functional outcome. RESULTS: We analyzed 1348 patients 610 (45.3%) of whom underwent CTP prerandomization. The benefit of EVT compared with best medical management was maintained irrespective of the baseline imaging paradigm (90-day modified Rankin Scale score 0-2 in EVT versus control patients: with CTP: 46.0% (137/298) versus 28.9% (88/305), without CTP: 44.1% (162/367) versus 27.3% (100/366). Performance of CTP baseline imaging compared with baseline noncontrast CT and CT angiography only yielded similar rates of good outcome (odds ratio, 1.05 [95% CI, 0.82-1.33], adjusted odds ratio, 1.04, [95% CI, 0.80-1.35]). CONCLUSIONS: Rates of good functional outcome were similar among patients in whom CTP was or was not performed, and EVT treatment effect in the 0- to 6-hour time window was similar in patients with and without baseline CTP imaging.