Signal intensity and volume of carotid intraplaque hemorrhage on magnetic resonance imaging and the risk of ipsilateral cerebrovascular events: The Plaque At RISK (PARISK) study.

BACKGROUND: The Plaque At RISK (PARISK) study demonstrated that patients with a carotid plaque with intraplaque hemorrhage (IPH) have an increased risk of recurrent ipsilateral ischemic cerebrovascular events. It was previously reported that symptomatic carotid plaques with IPH showed higher IPH signal intensity ratios (SIR) and larger IPH volumes than asymptomatic plaques. We explored whether IPH SIR and IPH volume are associated with future ipsilateral ischemic cerebrovascular events beyond the presence of IPH. METHODS: Transient ischemic attack and ischemic stroke patients with mild-to-moderate carotid stenosis and an ipsilateral IPH-positive carotid plaque (n = 89) from the PARISK study were included. The clinical endpoint was a new ipsilateral ischemic cerebrovascular event during 5 years of follow-up, while the imaging-based endpoint was a new ipsilateral brain infarct on brain magnetic resonance imaging (MRI) after 2 years (n = 69). Trained observers delineated IPH, a hyperintense region compared to surrounding muscle tissue on hyper T1-weighted magnetic resonance images. The IPH SIR was the maximal signal intensity in the IPH region divided by the mean signal intensity of adjacent muscle tissue. The associations between IPH SIR or volume and the clinical and imaging-based endpoint were investigated using Cox proportional hazard models and logistic regression, respectively. RESULTS: During 5.1 (interquartile range: 3.1-5.6) years of follow-up, 21 ipsilateral cerebrovascular ischemic events were identified. Twelve new ipsilateral brain infarcts were identified on the 2-year neuro MRI. There was no association for IPH SIR or IPH volume with the clinical endpoint (hazard ratio (HR): 0.89 [95% confidence interval: 0.67-1.10] and HR: 0.91 [0.69-1.19] per 100-µL increase, respectively) nor with the imaging-based endpoint (odds ratio (OR): 1.04 [0.75-1.45] and OR: 1.21 [0.87-1.68] per 100-µL increase, respectively). CONCLUSION: IPH SIR and IPH volume were not associated with future ipsilateral ischemic cerebrovascular events. Therefore, quantitative assessment of IPH of SIR and volume does not seem to provide additional value beyond the presence of IPH for stroke risk assessment. TRIAL REGISTRATION: The PARISK study was registered on ClinicalTrials.gov with ID NCT01208025 on September 21, 2010 (https://clinicaltrials.gov/study/NCT01208025).

Long-term colchicine for the prevention of vascular recurrent events in non-cardioembolic stroke (CONVINCE): a randomised controlled trial.

BACKGROUND: Anti-inflammatory therapy with long-term colchicine prevented vascular recurrence in coronary disease. Unlike coronary disease, which is typically caused by atherosclerosis, ischaemic stroke is caused by diverse mechanisms including atherosclerosis and small vessel disease or is frequently due to an unknown cause. We aimed to investigate the hypothesis that long-term colchicine would reduce recurrent events after ischaemic stroke. METHODS: We did a randomised, parallel-group, open-label, blinded endpoint assessed trial comparing long-term colchicine (0·5 mg orally per day) plus guideline-based usual care with usual care only. Hospital-based patients with non-severe, non-cardioembolic ischaemic stroke or high-risk transient ischaemic attack were eligible. The primary endpoint was a composite of first fatal or non-fatal recurrent ischaemic stroke, myocardial infarction, cardiac arrest, or hospitalisation (defined as an admission to an inpatient unit or a visit to an emergency department that resulted in at least a 24 h stay [or a change in calendar date if the hospital admission or discharge times were not available]) for unstable angina. The p value for significance was 0·048 to adjust for two prespecified interim analyses conducted by the data monitoring committee, for which the steering committee and trial investigators remained blinded. The trial was registered at ClinicalTrials.gov (NCT02898610) and is completed. FINDINGS: 3154 patients were randomly assigned between Dec 19, 2016, and Nov 21, 2022, with the last follow-up on Jan 31, 2024. The trial finished before the anticipated number of outcomes was accrued (367 outcomes planned) due to budget constraints attributable to the COVID-19 pandemic. Ten patients withdrew consent for analysis of their data, leaving 3144 patients in the intention-to-treat analysis: 1569 (colchicine and usual care) and 1575 (usual care alone). A primary endpoint occurred in 338 patients, 153 (9·8%) of 1569 patients allocated to colchicine and usual care and 185 (11·7%) of 1575 patients allocated to usual care alone (incidence rates 3·32 vs 3·92 per 100 person-years, hazard ratio 0·84; 95% CI 0·68-1·05, p=0·12). Although no between-group difference in C-reactive protein (CRP) was observed at baseline, patients treated with colchicine had lower CRP at 28 days and at 1, 2, and 3 years (p<0·05 for all timepoints). The rates of serious adverse events were similar in both groups. INTERPRETATION: Although no statistically significant benefit was observed on the primary intention-to-treat analysis, the findings provide new evidence supporting the rationale for anti-inflammatory therapy in further randomised trials. FUNDING: Health Research Board Ireland, Deutsche Forschungsgemeinschaft (German Research Foundation), and Fonds Wetenschappelijk Onderzoek Vlaanderen (Research Foundation Flanders), Belgium.

Safety and efficacy of active blood-pressure reduction to the recommended thresholds for intravenous thrombolysis in patients with acute ischaemic stroke in the Netherlands (TRUTH): a prospective, observational, cluster-based, parallel-group study.

BACKGROUND: Intravenous thrombolysis is contraindicated in patients with ischaemic stroke with blood pressure higher than 185/110 mm Hg. Prevailing guidelines recommend to actively lower blood pressure with intravenous antihypertensive agents to allow for thrombolysis; however, there is no robust evidence for this strategy. Because rapid declines in blood pressure can also adversely affect clinical outcomes, several Dutch stroke centres use a conservative strategy that does not involve the reduction of blood pressure. We aimed to compare the clinical outcomes of both strategies. METHODS: Thrombolysis and Uncontrolled Hypertension (TRUTH) was a prospective, observational, cluster-based, parallel-group study conducted across 37 stroke centres in the Netherlands. Participating centres had to strictly adhere to an active blood-pressure-lowering strategy or to a non-lowering strategy. Eligible participants were adults (≥18 years) with ischaemic stroke who had blood pressure higher than 185/110 mm Hg but were otherwise eligible for intravenous thrombolysis. The primary outcome was functional status at 90 days, measured using the modified Rankin Scale and assessed through telephone interviews by trained research nurses. Secondary outcomes were symptomatic intracranial haemorrhage, the proportion of patients treated with intravenous thrombolysis, and door-to-needle time. All ordinal logistic regression analyses were adjusted for age, sex, stroke severity, endovascular thrombectomy, and baseline imbalances as fixed-effect variables and centre as a random-effect variable to account for the clustered design. Analyses were done according to the intention-to-treat principle, whereby all patients were analysed according to the treatment strategy of the participating centre at which they were treated. FINDINGS: Recruitment began on Jan 1, 2015, and was prematurely halted because of a declining inclusion rate and insufficient funding on Jan 5, 2022. Between these dates, we recruited 853 patients from 27 centres that followed an active blood-pressure-lowering strategy and 199 patients from ten centres that followed a non-lowering strategy. Baseline characteristics of participants from the two groups were similar. The 90-day mRS score was missing for 15 patients. The adjusted odds ratio (aOR) for a shift towards a worse 90-day functional outcome was 1·27 (95% CI 0·96-1·68) for active blood-pressure reduction compared with no active blood-pressure reduction. 798 (94%) of 853 patients in the active blood-pressure-lowering group were treated with intravenous thrombolysis, with a median door-to-needle time of 35 min (IQR 25-52), compared with 104 (52%) of 199 patients treated in the non-lowering group with a median time of 47 min (29-78). 42 (5%) of 852 patients in the active blood-pressure-lowering group had a symptomatic intracranial haemorrhage compared with six (3%) of 199 of those in the non-lowering group (aOR 1·28 [95% CI 0·62-2·62]). INTERPRETATION: Insufficient evidence was available to establish a difference between an active blood-pressure-lowering strategy-in which antihypertensive agents were administered to reduce blood pressure below 185/110 mm Hg-and a non-lowering strategy for the functional outcomes of patients with ischaemic stroke, despite higher intravenous thrombolysis rates and shorter door-to-needle times among those in the active blood-pressure-lowering group. Randomised controlled trials are needed to inform the use of an active blood-pressure-lowering strategy. FUNDING: Fonds NutsOhra.

Trigger factors in patients with a patent foramen ovale-associated stroke: A case-crossover study.

BACKGROUND: Patent foramen ovale (PFO) is a congenital anatomical variant which is associated with strokes in young adults. Contrary to vascular risk factors and atherosclerosis, a PFO is present from birth. However, it is completely unknown how an anatomical structure that is already present at birth in a large proportion of the population can convert into a PFO that causes stroke in a few. Recent studies reported a significant association between certain trigger factors and ischemic stroke in young adults. This study aims to investigate these triggers in PFO-associated stroke. METHODS: The ODYSSEY study, a multicenter prospective cohort study between 2013 and 2021, included patients aged 18-49 years experiencing their first-ever ischemic event. Participants completed a questionnaire about exposure to potential trigger factors. A case-crossover design was used to assess the relative risks (RR) with 95% confidence intervals (95% CI). The primary outcome was the RR of potential trigger factors for PFO-associated stroke. RESULTS: Overall, 1043 patients completed the questionnaire and had an ischemic stroke, of which 124 patients had a PFO-associated stroke (median age 42.1 years, 45.2% men). For patients with PFO-associated stroke, the RR was 26.0 (95% CI 8.0-128.2) for fever, 24.2 (95% CI 8.5-68.7) for flu-like disease, and 3.31 (95% CI 2.2-5.1) for vigorous exercise. CONCLUSION: In conclusion, flu-like disease, fever, and vigorous exercise may convert an asymptomatic PFO into a stroke-causing PFO in young adults. DATA ACCESS STATEMENT: The raw and anonymized data used in this study can be made available to other researchers on request. Written proposals can be addressed to the corresponding author and will be assessed by the ODYSSEY investigators for appropriateness of use, and a data sharing agreement in accordance with Dutch regulations will be put in place before data are shared.

Short-Term and Long-Term Risk of Recurrent Vascular Event by Cause After Ischemic Stroke in Young Adults.

Importance: Cause of ischemic stroke in young people is highly variable; however, the risk of recurrence is often presented with all subtypes of stroke grouped together in classification systems such as the Trial of ORG (danaparoid sodium [Orgaran]) 10172 in Acute Stroke Treatment (TOAST) criteria, which limits the ability to individually inform young patients with stroke about their risk of recurrence. Objective: To determine the short-term and long-term risk of recurrent vascular events after ischemic stroke at a young age by stroke cause and to identify factors associated with recurrence. Design, Setting, and Participants: This cohort study used data from the Observational Dutch Young Symptomatic Stroke Study, a prospective, multicenter, hospital-based cohort study, conducted at 17 hospitals in the Netherlands between 2013 and 2021. Eligible participants included 30-day survivors of an initial, neuroimaging-proven ischemic stroke (aged 18-49 years). Data analysis was conducted from June to July 2023. Exposure: Diagnosis of a first-ever, ischemic stroke via neuroimaging. Main Outcome and Measures: The primary outcome was short-term (within 6 months) and long-term (within 5 years) recurrence risk of any vascular event, defined as fatal or nonfatal recurrent ischemic stroke, transient ischemic attack, myocardial infarction, and revascularization procedure. Predefined characteristics were chosen to identify factors associated with risk of recurrence (cause of stroke, age, sex, stroke severity, and cardiovascular health factors). Results: A total of 1216 patients (median [IQR] age, 44.2 [38.4-47.7] years; 632 male [52.0%]; 584 female [48.0%]) were included, with a median (IQR) follow-up of 4.3 (2.6-6.0) years. The 6-month risk of any recurrent ischemic event was 6.7% (95% CI, 5.3%-8.1%), and the 5-year risk was 12.2% (95% CI, 10.2%-14.2%)The short-term risk was highest for patients with cervical artery dissections (13.2%; 95% CI, 7.6%-18.7%). Other factors associated with a recurrent short-term event were atherothrombotic stroke, rare causes of stroke, and hypertension. The long-term cumulative risk was highest for patients with atherothrombotic stroke (22.7%; 95% CI, 10.6%-34.7%) and lowest for patients with cryptogenic stroke (5.8%; 95% CI, 3.0%-8.5%). Cardioembolic stroke was associated with a recurrent long-term event, as were diabetes and alcohol abuse. Conclusions and Relevance: The findings of this cohort study of 1216 patients with an ischemic stroke at a young age suggest that the risk of recurrent vascular events was high and varied by cause of stroke both for short-term and long-term follow-up, including causes that remained concealed when combined into 1 category in the routinely used TOAST criteria. This knowledge will allow for more personalized counseling of young patients with stroke.

Sex differences in clot, vessel and tissue characteristics in patients with a large vessel occlusion treated with endovascular thrombectomy.

INTRODUCTION: To improve our understanding of the relatively poor outcome after endovascular treatment (EVT) in women we assessed possible sex differences in baseline neuroimaging characteristics of acute ischemic stroke patients with large anterior vessel occlusion (LVO). PATIENTS AND METHODS: We included all consecutive patients from the MR CLEAN Registry who underwent EVT between 2014 and 2017. On baseline non-contrast CT and CT angiography, we assessed clot location and clot burden score (CBS), vessel characteristics (presence of atherosclerosis, tortuosity, size, and collateral status), and tissue characteristics with the Alberta Stroke Program Early Computed Tomography Score (ASPECTS). Radiological outcome was assessed with the extended thrombolysis in cerebral infarction score (eTICI) and functional outcome with the modified Rankin Scale score (mRS) at 90 days. Sex-differences were assessed with multivariable regression analyses with adjustments for possible confounders. RESULTS: 3180 patients were included (median age 72 years, 48% women). Clots in women were less often located in the intracranial internal carotid artery (ICA) (25%vs 28%, odds ratio (OR) 0.85;95% confidence interval: 0.73-1.00). CBS was similar between sexes (median 6, IQR 4-8). Intracranial (aOR 0.73;95% CI:0.62-0.87) and extracranial (aOR 0.64;95% CI:0.43-0.95) atherosclerosis was less prevalent in women. Vessel tortuosity was more frequent in women in the cervical ICA (aOR 1.89;95% CI:1.39-2.57) and women more often had severe elongation of the aortic arch (aOR 1.38;95% CI:1.00-1.91). ICA radius was smaller in women (2.3vs 2.5 mm, mean difference 0.22;95% CI:0.09-0.35) while M1 radius was essentially equal (1.6vs 1.7 mm, mean difference 0.09;95% CI:-0.02-0.21). Women had better collateral status (⩾50% filling in 62%vs 53% in men, aOR 1.48;95% CI:1.29-1.70). Finally, ASPECT scores were equal between women and men (median 9 in both sexes, IQR 8-10vs 9-10). Reperfusion rates were similar between women and men (acOR 0.94;95% CI:0.83-1.07). However, women less often reached functional independence than men (34%vs 46%, aOR 0.68;95% CI:0.53-0.86). DISCUSSION AND CONCLUSION: On baseline imaging of this Dutch Registry, men and women with LVO mainly differ in vessel characteristics such as atherosclerotic burden, extracranial vessel tortuosity, and collateral status. These sex differences do not result in different reperfusion rates and are, therefore, not likely to explain the worse functional outcome in women after EVT.

Immediate Carotid Artery Stenting or Deferred Treatment in Patients With Tandem Carotid Lesions Treated Endovascularly for Acute Ischaemic Stroke.

Fifteen to 20% of patients with an acute ischaemic stroke have a tandem lesion defined by the combination of an intracranial large vessel thrombo-embolic occlusion and a high grade stenosis or occlusion of the ipsilateral internal carotid artery. These patients tend to have worse outcomes than patients with isolated intracranial occlusions, with higher rates of disability and death. The introduction of endovascular thrombectomy to treat the intracranial lesion clearly improved the outcome compared with treatment with intravenous thrombolysis alone. However, the best treatment strategy for managing the extracranial carotid artery lesion in patients with tandem lesions remains unknown. Current guidelines recommend carotid endarterectomy for patients with transient ischaemic attack or non-disabling stroke and moderate or severe stenosis of the internal carotid artery, within two weeks of the initial event, to prevent major stroke recurrence and death. Alternatively, the symptomatic carotid artery could be treated by endovascular placement of a stent during endovascular thrombectomy (EVT). This would negate the need for a second procedure, immediately reduce the risk of stroke recurrence, increase patient satisfaction, and could be cost effective. However, the administration of dual antiplatelet therapy could potentially increase the risk of symptomatic intracranial haemorrhage in patients with acute ischaemic stroke. Randomised controlled trials evaluating the efficacy and safety of immediate carotid artery stenting during EVT in acute stroke patients with tandem lesions are currently ongoing and will impact the current guidelines regarding the treatment of patients with acute ischaemic stroke due to these tandem lesions.

Sex differences in outcomes after endovascular treatment in posterior circulation stroke: results from the MR CLEAN Registry.

BACKGROUND: Women with anterior circulation large vessel occlusion (LVO) have been reported to have worse outcomes after endovascular treatment (EVT) than men. Whether these disparities also exist in LVO of the posterior circulation is yet uncertain. We assessed sex differences in clinical, technical, and safety outcomes of EVT in posterior circulation LVO. METHODS: We used data of patients with posterior circulation LVO included in the Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands (MR CLEAN) Registry (2014-2018). Primary outcome was the modified Rankin Scale (mRS) score at 90 days assessed with multivariable ordinal regression analysis. Secondary outcomes included favorable functional outcome (mRS ≤3), functional independence (mRS ≤2), death within 90 days, National Institutes of Health Stroke Scale (NIHSS) score 24-48 hours postintervention, complications, successful reperfusion (extended Thrombolysis in Cerebral Ischemia 2B-3), and procedure duration analyzed with multivariable logistic and linear regression analyses. RESULTS: We included 264 patients (42% women). Compared with men, women were older (median age 68 vs 63 years), more often had prestroke disability (mRS ≥1: 37% vs 30%), and received intravenous thrombolytics less often (45% vs 56%). Clinical outcomes were similar between sexes (adjusted (common) OR (aOR) 0.82, 95% CI 0.51 to 1.34; favorable functional outcome 50% vs 43%, aOR 1.31, 95% CI 0.77 to 2.25; death 32% vs 29%, aOR 0.98, 95% CI 0.52 to 1.84). In addition, NIHSS score after 24-48 hours (median 7 vs 9), successful reperfusion (77% vs 73%), and complications did not differ between men and women. CONCLUSIONS: Outcomes in women treated with EVT for posterior circulation LVO were similar compared with men despite less favorable baseline characteristics in women. Therefore men and women may benefit equally from EVT.

Recent advances and controversial issues in the optimal management of asymptomatic carotid stenosis.

OBJECTIVE: The optimal management of patients with asymptomatic carotid stenosis (AsxCS) is enduringly controversial. We updated our 2021 Expert Review and Position Statement, focusing on recent advances in the diagnosis and management of patients with AsxCS. METHODS: A systematic review of the literature was performed up to August 1, 2023, using PubMed/PubMed Central, EMBASE and Scopus. The following keywords were used in various combinations: "asymptomatic carotid stenosis," "carotid endarterectomy" (CEA), "carotid artery stenting" (CAS), and "transcarotid artery revascularization" (TCAR). Areas covered included (i) improvements in best medical treatment (BMT) for patients with AsxCS and declining stroke risk, (ii) technological advances in surgical/endovascular skills/techniques and outcomes, (iii) risk factors, clinical/imaging characteristics and risk prediction models for the identification of high-risk AsxCS patient subgroups, and (iv) the association between cognitive dysfunction and AsxCS. RESULTS: BMT is essential for all patients with AsxCS, regardless of whether they will eventually be offered CEA, CAS, or TCAR. Specific patient subgroups at high risk for stroke despite BMT should be considered for a carotid revascularization procedure. These patients include those with severe (≥80%) AsxCS, transcranial Doppler-detected microemboli, plaque echolucency on Duplex ultrasound examination, silent infarcts on brain computed tomography or magnetic resonance angiography scans, decreased cerebrovascular reserve, increased size of juxtaluminal hypoechoic area, AsxCS progression, carotid plaque ulceration, and intraplaque hemorrhage. Treatment of patients with AsxCS should be individualized, taking into consideration individual patient preferences and needs, clinical and imaging characteristics, and cultural, ethnic, and social factors. Solid evidence supporting or refuting an association between AsxCS and cognitive dysfunction is lacking. CONCLUSIONS: The optimal management of patients with AsxCS should include BMT for all individuals and a prophylactic carotid revascularization procedure (CEA, CAS, or TCAR) for some asymptomatic patient subgroups, additionally taking into consideration individual patient needs and preference, clinical and imaging characteristics, social and cultural factors, and the available stroke risk prediction models. Future studies should investigate the association between AsxCS with cognitive function and the role of carotid revascularization procedures in the progression or reversal of cognitive dysfunction.

Cognitive trajectory in the first year after first-ever ischaemic stroke in young adults: the ODYSSEY study.

BACKGROUND: Limited data exists on cognitive recovery in young stroke patients. We aimed to investigate the longitudinal course of cognitive performance during the first year after stroke at young age and identify predictors for cognitive recovery. METHODS: We conducted a multicentre prospective cohort study between 2013 and 2021, enrolling patients aged 18-49 years with first-ever ischaemic stroke. Cognitive assessments were performed within 6 months and after 1 year following the index event, covering seven cognitive domains. Composite Z-scores using normative data determined cognitive impairment (Z-score<-1.5). A Reliable Change Index (RCI) assessed cognitive recovery (RCI>1.96) or decline (RCI<-1.96). RESULTS: 393 patients (median age 44.3 years, IQR 38.4-47.2) completed cognitive assessments with a median time interval of 403 days (IQR 364-474) between assessments. Based on RCI, a similar proportion of patients showed improvement and decline in each cognitive domain, while the majority exhibited no cognitive change. Among cognitively impaired patients at baseline, improvements were observed in processing speed (23.1%), visuoconstruction (40.1%) and executive functioning (20.0%). Younger age was associated with better cognitive recovery in visuoconstruction, and larger lesion volume was related to cognitive recovery in processing speed. No other predictors for cognitive recovery were identified. CONCLUSIONS: Cognitive impairment remains prevalent in young stroke even 1 year after the event. Most patients showed no cognitive change, however, recovery may have occurred in the early weeks after stroke, which was not assessed in our study. Among initially cognitively impaired patients, cognitive recovery is observed in processing speed, visuoconstruction and executive functioning. It is still not possible to predict cognitive recovery in individual patients.

The association between antiplatelet therapy and changes in intraplaque hemorrhage in patients with mild to moderate symptomatic carotid stenosis: a longitudinal MRI study.

INTRODUCTION: Carotid atherosclerotic intraplaque hemorrhage (IPH) predicts stroke. Patients with a history of stroke are treated with antiplatelet agents to prevent secondary cardiovascular events. A positive association between previous antiplatelet use and IPH was reported in a cross-sectional analysis. We investigated changes in IPH over two years in patients who recently started versus those with continued antiplatelet use. METHODS: In the Plaque at Risk (PARISK) study, symptomatic patients with <70% ipsilateral carotid stenosis underwent carotid plaque MRI at baseline and after two years to determine IPH presence and volume. Participants were categorized into new users (starting antiplatelet therapy following the index event) and continued users (previous use of antiplatelet therapy before the index event). The association between previous antiplatelet therapy and the presence of IPH at baseline MRI was investigated using multivariable logistic regression analysis. IPH volume change over a period of two years, defined as the difference in volume between follow-up and baseline, was investigated in each group with a Wilcoxon signed-rank test. The IPH volume change was categorized as progression, regression, or no change. Using multivariable logistic regression, we investigated the association between new antiplatelet use and 1) newly developed ipsilateral or contralateral IPH and 2) IPH volume progression. RESULTS: A total of 108 patients underwent carotid MRI at baseline and follow-up. At baseline, previous antiplatelet therapy was associated with any IPH (OR=5.6, 95% CI: 1.3-23.1; p=0.02). Ipsilateral IPH volume did not change significantly during the two years in patients who continued receiving antiplatelet agents (86.4 mm3 [18.2-235.9] vs. 59.3 mm3 [11.4-260.3]; p=0.6) nor in the new antiplatelet users (n=31) (61.5 mm3 [0.0-166.9] vs. 27.7 mm3 [9.5-106.4]; p=0.4). Similar results of a nonsignificant change in contralateral IPH volume during those two years were observed in both groups (p>0.05). No significant associations were found between new antiplatelet use and newly developed IPH at two years (odds ratio (OR)=1.0, 95% CI:0.1-7.4) or the progression of IPH (ipsilateral: OR=2.4, 95% CI:0.3-19.1; contralateral: OR=0.3, 95% CI:0.01-8.5). CONCLUSION: Although the baseline association between IPH and previous antiplatelet therapy was confirmed in this larger cohort, the new onset of antiplatelet therapy after TIA/stroke was not associated with newly developed IPH or progression of IPH volume over the subsequent two years.

Application of mask images of contrast-enhanced MR angiography to detect carotid intraplaque hemorrhage in patients with moderate to severe symptomatic and asymptomatic carotid stenosis.

PURPOSE: Carotid intraplaque hemorrhage (IPH) on MRI predicts stroke. Magnetization-prepared rapid acquisition gradient (MP-RAGE) is widely used to detect IPH. CE-MRA is used routinely to assess stenosis. Initial studies indicated that IPH can be identified on mask images of CE-MRA, while Time-of-Flight (TOF) images were reported to have high specificity but lower sensitivity. We investigated the diagnostic accuracy of detecting IPH on mask images of CE-MRA and TOF. METHODS: Thirty-six patients with ≥ 50% stenosis enrolled in the ongoing 2nd European Carotid Surgery Trial underwent carotid MRI. A 5-point quality score was used. Inter-observer agreement between two independent readers was determined. The sensitivity and specificity of IPH detection on mask MRA and TOF were calculated with MP-RAGE as a reference standard. RESULTS: Of the 36 patients included in the current analysis, 66/72 carotid arteries could be scored. The inter-observer agreements for identifying IPH on MP-RAGE, mask, and TOF were outstanding (κ: 0.93, 0.96, and 0.85). The image quality of mask (1.42 ± 0.66) and TOF (2.42 ± 0.66) was significantly lower than MP-RAGE (3.47 ± 0.61). When T1w images were used to delineate the outer carotid wall, very high specificities (>95%) of IPH detection on mask and TOF images were found, while the sensitivity was high for mask images (>81%) and poor for TOF (50-60%). Without these images, the specificity was still high (>97%), while the sensitivity reduced to 62-71%. CONCLUSION: Despite the lower image quality, routinely acquired mask images from CE-MRA, but not TOF, can be used as an alternative to MP-RAGE images to visualize IPH.

Nested star-shaped objects segmentation using diameter annotations.

Most current deep learning based approaches for image segmentation require annotations of large datasets, which limits their application in clinical practice. We observe a mismatch between the voxelwise ground-truth that is required to optimize an objective at a voxel level and the commonly used, less time-consuming clinical annotations seeking to characterize the most important information about the patient (diameters, counts, etc.). In this study, we propose to bridge this gap for the case of multiple nested star-shaped objects (e.g., a blood vessel lumen and its outer wall) by optimizing a deep learning model based on diameter annotations. This is achieved by extracting in a differentiable manner the boundary points of the objects at training time, and by using this extraction during the backpropagation. We evaluate the proposed approach on segmentation of the carotid artery lumen and wall from multisequence MR images, thus reducing the annotation burden to only four annotated landmarks required to measure the diameters in the direction of the vessel's maximum narrowing. Our experiments show that training based on diameter annotations produces state-of-the-art weakly supervised segmentations and performs reasonably compared to full supervision. We made our code publicly available at https://gitlab.com/radiology/aim/carotid-artery-image-analysis/nested-star-shaped-objects.

Handling missing values in the analysis of between-hospital differences in ordinal and dichotomous outcomes: a simulation study.

Missing data are frequently encountered in registries that are used to compare performance across hospitals. The most appropriate method for handling missing data when analysing differences in outcomes between hospitals with a generalised linear mixed model is unclear. We aimed to compare methods for handling missing data when comparing hospitals on ordinal and dichotomous outcomes. We performed a simulation study using data from the Multicentre Randomised Controlled Trial of Endovascular Treatment for Acute Ischaemic Stroke in the Netherlands (MR CLEAN) Registry, a prospective cohort study in 17 hospitals performing endovascular therapy for ischaemic stroke in the Netherlands. The investigated methods for handling missing data, both case-mix adjustment variables and outcomes, were complete case analysis, single imputation, multiple imputation, single imputation with deletion of imputed outcomes and multiple imputation with deletion of imputed outcomes. Data were generated as missing completely at random (MCAR), missing at random and missing not at random (MNAR) in three scenarios: (1) 10% missing data in case-mix and outcome; (2) 40% missing data in case-mix and outcome; and (3) 40% missing data in case-mix and outcome with varying degree of missing data among hospitals. Bias and reliability of the methods were compared on the mean squared error (MSE, a summary measure combining bias and reliability) relative to the hospital effect estimates from the complete reference data set. For both the ordinal outcome (ie, the modified Rankin Scale) and a common dichotomised version thereof, all methods of handling missing data were biased, likely due to shrinkage of the random effects. The MSE of all methods was on average lowest under MCAR and with fewer missing data, and highest with more missing data and under MNAR. The 'multiple imputation, then deletion' method had the lowest MSE for both outcomes under all simulated patterns of missing data. Thus, when estimating hospital effects on ordinal and dichotomous outcomes in the presence of missing data, the least biased and most reliable method to handle these missing data is 'multiple imputation, then deletion'.

Admission blood pressure and clinical outcomes in patients with acute ischaemic stroke treated with intravenous alteplase and endovascular treatment versus endovascular treatment alone: A MR CLEAN-NO IV substudy.

INTRODUCTION: High systolic blood pressure (SBP) is associated with poor functional outcome. We analysed whether the association of SBP with outcomes after endovascular treatment (EVT) is modified by prior intravenous thrombolysis (IVT). PATIENTS AND METHODS: This was a post-hoc analysis of MR CLEAN-NO IV, a randomised trial of IVT with alteplase followed by EVT versus EVT alone, within 4.5 h from stroke onset. SBP was recorded on hospital admission. The primary outcome was 90-day modified Rankin Scale (mRS) score and secondary outcomes included symptomatic intracranial haemorrhage (sICH) and successful reperfusion (eTICI 2b-3), analysed with (ordinal) logistic regression. Estimates were calculated per 10 mmHg change in SBP. We assessed whether IVT modified the associations of SBP with these outcomes using multiplicative interaction terms. RESULTS: Of 539 randomised patients, 266 received IVT. The association of SBP with mRS score was J-shaped, with an inflection point at 150 mmHg. Using 150 mmHg as a reference point, SBPs higher than 150 mmHg were associated with poor functional outcome (acOR: 1.23, 95% CI: 1.09-1.38), but lower SBPs were not (acOR: 1.14, 95% CI: 0.99-1.30). Higher SBP was not associated with the risk of sICH (aOR: 1.09, 95% CI: 0.93-1.27) nor with the probability of successful reperfusion (aOR: 1.00, 95% CI: 0.91-1.10). Our main result was that we found no effect modification by IVT (p-values for interaction, mRS = 0.94; sICH = 0.26; successful reperfusion = 0.58). DISCUSSION AND CONCLUSION: There was no effect modification of IVT with SBP for any of the clinical outcomes. Therefore, the level of SBP (if ⩽185/110 mmHg) should not guide IVT decisions in patients otherwise eligible for both IVT and EVT within the 4.5-h time window. TRIAL REGISTRATION: ISRCTN80619088, https://www.isrctn.com/ISRCTN80619088.

Safety and effectiveness of IV Thrombolysis in retinal artery occlusion: A multicenter retrospective cohort study.

BACKGROUND: Retinal artery occlusion (RAO) may lead to irreversible blindness. For acute RAO, intravenous thrombolysis (IVT) can be considered as treatment. However, due to the rarity of RAO, data about IVT safety and effectiveness is limited. METHODS: From the multicenter database ThRombolysis for Ischemic Stroke Patients (TRISP), we retrospectively analyzed visual acuity (VA) at baseline and within 3 months in IVT and non-IVT treated RAO patients. Primary outcome was difference of VA between baseline and follow up (∆VA). Secondary outcomes were rates of visual recovery (defined as improvement of VA ⩾ 0.3 logMAR), and safety (symptomatic intracranial hemorrhage (sICH) according to ECASS II criteria, asymptomatic intracranial hemorrhage (ICH) and major extracranial bleeding). Statistical analysis was performed using parametric tests and a linear regression model adjusted for age, sex and baseline VA. RESULTS: We screened 200 patients with acute RAO and included 47 IVT and 34 non-IVT patients with complete information about recovery of vision. Visual Acuity at follow up significantly improved compared to baseline in IVT patients (∆VA 0.5 ± 0.8, p < 0.001) and non-IVT patients (∆VA 0.40 ± 1.1, p < 0.05). No significant differences in ∆VA and visual recovery rate were found between groups at follow up. Two asymptomatic ICH (4%) and one (2%) major extracranial bleeding (intraocular bleeding) occurred in the IVT group, while no bleeding events were reported in the non-IVT group. CONCLUSION: Our study provides real-life data from the largest cohort of IVT treated RAO patients published so far. While there is no evidence for superiority of IVT compared to conservative treatment, bleeding rates were low. A randomized controlled trial and standardized outcome assessments in RAO patients are justified to assess the net benefit of IVT in RAO.

Recanalization Therapies for Large Vessel Occlusion Due to Cervical Artery Dissection: A Cohort Study of the EVA-TRISP Collaboration.

BACKGROUND AND PURPOSE: This study aimed to investigate the effect of endovascular treatment (EVT, with or without intravenous thrombolysis [IVT]) versus IVT alone on outcomes in patients with acute ischemic stroke (AIS) and intracranial large vessel occlusion (LVO) attributable to cervical artery dissection (CeAD). METHODS: This multinational cohort study was conducted based on prospectively collected data from the EVA-TRISP (EndoVAscular treatment and ThRombolysis for Ischemic Stroke Patients) collaboration. Consecutive patients (2015-2019) with AIS-LVO attributable to CeAD treated with EVT and/or IVT were included. Primary outcome measures were (1) favorable 3-month outcome (modified Rankin Scale score 0-2) and (2) complete recanalization (thrombolysis in cerebral infarction scale 2b/3). Odds ratios with 95% confidence intervals (OR [95% CI]) from logistic regression models were calculated (unadjusted, adjusted). Secondary analyses were performed in the patients with LVO in the anterior circulation (LVOant) including propensity score matching. RESULTS: Among 290 patients, 222 (76.6%) had EVT and 68 (23.4%) IVT alone. EVT-treated patients had more severe strokes (National Institutes of Health Stroke Scale score, median [interquartile range]: 14 [10-19] vs. 4 [2-7], P<0.001). The frequency of favorable 3-month outcome did not differ significantly between both groups (EVT: 64.0% vs. IVT: 86.8%; ORadjusted 0.56 [0.24-1.32]). EVT was associated with higher rates of recanalization (80.5% vs. 40.7%; ORadjusted 8.85 [4.28-18.29]) compared to IVT. All secondary analyses showed higher recanalization rates in the EVT-group, which however never translated into better functional outcome rates compared to the IVT-group. CONCLUSION: We observed no signal of superiority of EVT over IVT regarding functional outcome in CeAD-patients with AIS and LVO despite higher rates of complete recanalization with EVT. Whether pathophysiological CeAD-characteristics or their younger age might explain this observation deserves further research.

Intravenous Thrombolysis 4.5-9 Hours After Stroke Onset: A Cohort Study from the TRISP Collaboration.

OBJECTIVE: To investigate the safety and effectiveness of intravenous thrombolysis (IVT) >4.5-9 hours after stroke onset, and the relevance of advanced neuroimaging for patient selection. METHODS: Prospective multicenter cohort study from the ThRombolysis in Ischemic Stroke Patients (TRISP) collaboration. Outcomes were symptomatic intracranial hemorrhage, poor 3-month functional outcome (modified Rankin scale 3-6) and mortality. We compared: (i) IVT >4.5-9 hours versus 0-4.5 hours after stroke onset and (ii) within the >4.5-9 hours group baseline advanced neuroimaging (computed tomography perfusion, magnetic resonance perfusion or magnetic resonance diffusion-weighted imaging fluid-attenuated inversion recovery) versus non-advanced neuroimaging. RESULTS: Of 15,827 patients, 663 (4.2%) received IVT >4.5-9 hours and 15,164 (95.8%) within 4.5 hours after stroke onset. The main baseline characteristics were evenly distributed between both groups. Time of stroke onset was known in 74.9% of patients treated between >4.5 and 9 hours. Using propensity score weighted binary logistic regression analysis (onset-to-treatment time >4.5-9 hours vs onset-to-treatment time 0-4.5 hours), the probability of symptomatic intracranial hemorrhage (ORadjusted 0.80, 95% CI 0.53-1.17), poor functional outcome (ORadjusted 1.01, 95% CI 0.83-1.22), and mortality (ORadjusted 0.80, 95% CI 0.61-1.04) did not differ significantly between both groups. In patients treated between >4.5 and 9 hours, the use of advanced neuroimaging was associated with a 50% lower mortality compared with non-advanced imaging only (9.9% vs 19.7%; ORadjusted 0.51, 95% CI 0.33-0.79). INTERPRETATION: This study showed no evidence in difference of symptomatic intracranial hemorrhage, poor outcome, and mortality in selected stroke patients treated with IVT between >4.5 and 9 hours after stroke onset compared with those treated within 4.5 hours. Advanced neuroimaging for patient selection was associated with lower mortality. ANN NEUROL 2023;94:309-320.

Subacute cognitive impairment after first-ever transient ischemic attack or ischemic stroke in young adults: The ODYSSEY study.

Introduction: We aimed to investigate the prevalence of cognitive impairment in the subacute phase after transient ischemic attack (TIA) and ischemic stroke (IS), factors associated with a vascular cognitive disorder, and the prevalence of subjective cognitive complaints and their relation with objective cognitive performance. Patients and methods: In this multicenter prospective cohort study, we recruited patients with first-ever TIA and IS, aged 18-49 years, between 2013 and 2021 for cognitive assessment up to 6 months after index event. We calculated composite Z-scores for seven cognitive domains. We defined cognitive impairment as a composite Z-score < -1.5. We defined major vascular cognitive disorder as a Z-score < -2.0 in one or more cognitive domains. Results: Fifty three TIA and 545 IS patients completed cognitive assessment with mean time to assessment of 89.7 (SD 40.7) days. The median NIHSS at admission was 3 (interquartile range, 1-5). Cognitive impairment was common in five domains (up to 37%), with similar proportion in TIA and IS patients. Patients with major vascular cognitive disorder had a lower education level, higher NIHSS scores and more frequent lesions in the left frontotemporal lobe than without vascular cognitive disorder (p < 0.05 FDR-corrected). Subjective memory and executive cognitive complaints were present in about two-thirds of the patients, but were weakly associated with objective cognitive performance (ß: -0.32 and -0.21, respectively). Discussion and conclusion: In the subacute phase after TIA or stroke in young adults, cognitive impairment and subjective cognitive complaints are prevalent, but they are weakly associated with each other.

Higher Leukocyte Count Is Associated with Lower Presence of Carotid Lipid-Rich Necrotic Core: A Sub-Study in the Plaque at RISK (PARISK) Study.

BACKGROUND: Increasing evidence suggests that inflammation inside the vessel wall has a prominent role in atherosclerosis. In carotid atherosclerosis in particular, vulnerable plaque characteristics are strongly linked to an increased stroke risk. An association between leukocytes and plaque characteristics has not been investigated before and could help with gaining knowledge on the role of inflammation in plaque vulnerability, which could contribute to a new target for intervention. In this study, we investigated the association of the leukocyte count with carotid vulnerable plaque characteristics. METHODS: All patients from the Plaque At RISK (PARISK) study whom had complete data on their leukocyte count and CTA- and MRI-based plaque characteristics were included. Univariable logistic regression was used to detect associations of the leukocyte count with the separate plaque characteristics (intra-plaque haemorrhage (IPH), lipid-rich-necrotic core (LRNC), thin or ruptured fibrous cap (TRFC), plaque ulceration and plaque calcifications). Subsequently, other known risk factors for stroke were included as covariates in a multivariable logistic regression model. RESULTS: 161 patients were eligible for inclusion in this study. Forty-six (28.6%) of these patients were female with a mean age of 70 [IQR 64-74]. An association was found between a higher leukocyte count and lower prevalence of LRNC (OR 0.818 (95% CI 0.687-0.975)) while adjusting for covariates. No associations were found between the leucocyte count and the presence of IPH, TRFC, plaque ulceration or calcifications. CONCLUSIONS: The leukocyte count is inversely associated with the presence of LRNC in the atherosclerotic carotid plaque in patients with a recently symptomatic carotid stenosis. The exact role of leukocytes and inflammation in plaque vulnerability deserves further attention.