Martin M. Brown

Randomized trials in stroke often focus on outcomes beyond a single clinical event. Trials of stroke prevention commonly use composite outcomes that include multiple components (eg, death, stroke, or myocardial infarction). A major limitation is that all events count equally but may differ markedly in terms of clinical severity. Trials in acute stroke often use ordinal outcomes or scale scores. Limitations include the requirement for statistical assumptions and the difficulty of handling the competing risk of death. We introduce the win ratio as an alternative method. It works by placing components of a composite into a hierarchy, whereby clinically more important outcomes take priority over less important ones. We illustrate how it works using data from 2 major stroke trials: the ICSS (International Carotid Stenting Study, a trial in stroke prevention) and the MR CLEAN (Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands). Potential benefits of the win ratio approach include the possibility to (1) emphasize the clinically most important outcomes, (2) combine components of different outcome types into a composite (eg, a mixture of time-to-event, continuous, and categorical), and (3) naturally handle the competing risk of death in analyses of quantitative outcomes. The win ratio will be used in the upcoming analysis of the ECST-2 (Second European Carotid Surgery Trial), which has a hierarchical primary outcome of (1) time to perioperative death, fatal stroke, or fatal myocardial infarction (most important); (2) time to nonfatal stroke; (3) time to nonfatal myocardial infarction (excluding silent infarcts); and (4) new silent cerebral infarct on brain imaging (least important). The win ratio provides a useful clinically relevant method for analyzing trial outcomes. It has some advantages over conventional methods, and we recommend its wider application in future stroke trials.

Background: Carotid endarterectomy is currently recommended for patients with recently symptomatic carotid stenosis ≥50%, based on randomised trials conducted 30 years ago. Several factors such as carotid plaque ulceration, age and associated comorbidities might influence the risk-benefit ratio of carotid revascularisation. A model developed in previous trials that calculates the future risk of stroke based on these features can be used to stratify patients into low, intermediate or high risk. Since the original trials, medical treatment has improved significantly. Our hypothesis is that patients with carotid stenosis ≥50% associated with a low to intermediate risk of stroke will not benefit from additional carotid revascularisation when treated with optimised medical therapy. We also hypothesise that prediction of future risk of stroke in individual patients with carotid stenosis can be improved using the results of magnetic resonance imaging (MRI) of the carotid plaque. Methods: Patients are randomised between immediate revascularisation plus OMT versus OMT alone. Suitable patients are those with asymptomatic or symptomatic carotid stenosis ≥50% with an estimated 5-year risk of stroke of <20%, as calculated using the Carotid Artery Risk score. MRI of the brain at baseline and during follow-up will be used as a blinded measure to assess the incidence of silent infarction and haemorrhage, while carotid plaque MRI at baseline will be used to investigate the hypotheses that plaque characteristics determine future stroke risk and help identify a subgroup of patients that will benefit from revascularisation. An initial analysis will be conducted after recruitment of 320 patients with baseline MRI and a minimum of 2 years of follow-up, to provide data to inform the design and sample size for a continuation or re-launch of the study. The primary outcome measure of this initial analysis is the combined 2-year rate of any clinically manifest stroke, new cerebral infarct on MRI, myocardial infarction or periprocedural death. Discussion: ECST-2 will provide new data on the efficacy of modern optimal medical therapy alone versus added carotid revascularisation in patients with carotid stenosis at low to intermediate risk of future stroke selected by individualised risk assessment. We anticipate that the results of baseline brain and carotid plaque MRI will provide data to improve the prediction of the risk of stroke and the effect of treatment in patients with carotid stenosis. Trial registration: ISRCTN registry ISRCTN97744893. Registered on 05 July 2012

Objective: To investigate the safety and effectiveness of direct oral anticoagulants (DOAC) versus vitamin K antagonists (VKA) after recent stroke in patients with atrial fibrillation (AF) aged ≥85 years.Methods: Individual patient data analysis from seven prospective stroke cohorts. We compared DOAC versus VKA treatment among patients with AF and recent stroke (≥85y = 0.65, 95%‐CI [0.52, 0.81]) and < 85 years (HR _{= 0.79, 95%‐CI [0.66, 0.95]) in simple (pinteraction = 0.129), adjusted (pinteraction = 0.094) or weighted (pinteraction = 0.512) models. Analyses on recurrent stroke, ICH and death separately were consistent with the primary analysis, as were sensitivity analyses using age dichotomized at 90 years and as a continuous variable. DOAC had a similar net clinical benefit in patients aged ≥85 (+1.73 to +2.66) and < 85 years (+1.90 to +3.36 events/100 patient‐years for ICH‐weights 1.5 to 3.1).Interpretation: The favorable profile of DOAC over VKA in patients with AF and recent stroke was maintained in the oldest old. ANN NEUROL 2022;91:78–88}

SUMMARY: Current guidelines for primary and secondary prevention of stroke in patients with carotid atherosclerosis are based on the quantification of the degree of stenosis and symptom status. Recent publications have demonstrated that plaque morphology and composition, independent of the degree of stenosis, are important in the risk stratification of carotid atherosclerotic disease. This finding raises the question as to whether current guidelines are adequate or if they should be updated with new evidence, including imaging for plaque phenotyping, risk stratification, and clinical decision-making in addition to the degree of stenosis. To further this discussion, this roadmap consensus article defines the limits of luminal imaging and highlights the current evidence supporting the role of plaque imaging. Furthermore, we identify gaps in current knowledge and suggest steps to generate high-quality evidence, to add relevant information to guidelines currently based on the quantification of stenosis.