Timing of anticoagulation therapy in patients with acute ischaemic stroke and atrial fibrillation

Early vs Late Anticoagulation in Minor, Moderate, and Major Ischemic Stroke With Atrial Fibrillation: Post Hoc Analysis of the ELAN Randomized Clinical Trial

Importance

Whether infarct size modifies the treatment effect of early vs late direct oral anticoagulant (DOAC) initiation in people with ischemic stroke and atrial fibrillation is unknown.

Objective

To assess whether infarct size modifies the safety and efficacy of early vs late DOAC initiation.

Design, Setting, and Participants

Post hoc analysis of participants from the multinational (>100 sites in 15 countries) randomized clinical Early Versus Later Anticoagulation for Stroke With Atrial Fibrillation (ELAN) trial who had (1) acute ischemic stroke, (2) atrial fibrillation, and (3) brain imaging available before randomization. The ELAN trial was conducted between October 2017 and December 2022. Data were analyzed from October to December 2023 for this post hoc analysis.

Intervention

Early vs late DOAC initiation after ischemic stroke. Early DOAC initiation was within 48 hours for minor or moderate stroke or on days 6 to 7 for major stroke; late DOAC initiation was on days 3 to 4 for minor stroke, days 6 to 7 for moderate stroke, and days 12 to 14 for major stroke.

Main Outcomes and Measures

The primary outcome was a composite of recurrent ischemic stroke, symptomatic intracranial hemorrhage, extracranial bleeding, systemic embolism, or vascular death within 30 days. The outcome was assessed according to infarct size (minor, moderate, or major) using odds ratios and risk differences between treatment arms. Interrater reliability for infarct size between the core laboratory and local raters was assessed, and whether this modified the estimated treatment effects was also examined.

Results

A total of 1962 of the original 2013 participants (909 [46.3%] female; median [IQR] age, 77 [70-84] years) were included. The primary outcome occurred in 10 of 371 participants (2.7%) with early DOAC initiation vs 11 of 364 (3.0%) with late DOAC initiation among those with minor stroke (odds ratio [OR], 0.89; 95% CI, 0.38-2.10); in 11 of 388 (2.8%) with early DOAC initiation vs 14 of 392 (3.6%) with late DOAC initiation among those with moderate stroke (OR, 0.80; 95% CI, 0.35-1.74); and in 8 of 219 (3.7%) with early DOAC initiation vs 16 of 228 (7.0%) with late DOAC initiation among those with major stroke (OR, 0.52; 95% CI, 0.21-1.18). The 95% CI for the estimated risk difference of the primary outcome in early anticoagulation was -2.78% to 2.12% for minor stroke, -3.23% to 1.76% for moderate stroke, and -7.49% to 0.81% for major stroke. There was no significant treatment interaction for the primary outcome. For infarct size, interrater reliability was moderate (κ = 0.675; 95% CI, 0.647-0.702) for local vs core laboratory raters and strong (κ = 0.875; 95% CI, 0.855-0.894) between core laboratory raters.

Conclusions and Relevance

The treatment effect of early DOAC initiation did not differ in people with minor, moderate, or major stroke assessed by brain imaging. Early treatment was not associated with a higher rate of adverse events, especially symptomatic intracranial hemorrhage, for any infarct size, including major stroke.

Trial Registration

ClinicalTrials.gov Identifier: NCT03148457.

Early versus Late initiation of direct oral Anticoagulants in post-ischaemic stroke patients with atrial fibrillatioN (ELAN): Protocol for an international, multicentre, randomised-controlled, two-arm, open, assessor-blinded trial

RATIONALE

Direct oral anticoagulants (DOAC) are highly effective in preventing ischaemic strokes in people with atrial fibrillation (AF). However, it is unclear how soon they should be started after acute ischaemic stroke (AIS). Early initiation may reduce early risk of recurrence but might increase the risk of haemorrhagic complications.

AIM

To estimate the safety and efficacy of early initiation of DOACs compared to late guideline-based initiation in people with AIS related to AF.

METHODS AND DESIGN

An international, multicentre, randomised (1:1) controlled, two-arm, open, assessor-blinded trial is being conducted. Early treatment is defined as DOAC initiation within 48 h of a minor or moderate stroke, or at day 6-7 following major stroke. Late treatment is defined as DOAC initiation after day 3-4 following minor stroke, after day 6-7 following moderate stroke and after day 12-14 following major stroke. Severity of stroke is defined according to imaging assessment of infarct size.

SAMPLE SIZE

ELAN will randomise 2000 participants 1:1 to early versus late initiation of DOACs. This assumes a risk difference of 0.5% favouring the early arm, allowing an upper limit of the 95% confidence interval up to 1.5% based on the Miettinen & Nurminen formula.

OUTCOMES

The primary outcome is a composite of symptomatic intracranial haemorrhage, major extracranial bleeding, recurrent ischaemic stroke, systemic embolism or vascular death at 30 ± 3 days after randomisation. Secondary outcomes include the individual components of the primary outcome at 30 ± 3 and 90 ± 7 days and functional status at 90 ± 7 days.

DISCUSSION

ELAN will estimate whether there is a clinically important difference in safety and efficacy outcomes following early anticoagulation with a DOAC compared to late guideline-based treatment in neuroimaging-selected people with an AIS due to AF.

Successful use of therapeutic anticoagulation therapy in two patients with moderate stroke from the second day of onset: A case report and literature review

Introduction and importance

Hemorrhagic transformation of ischemic stroke is one of the most traumatic consequences of ischemic stroke. Therefore, deciding the optimal time for anticoagulant application and its effect on clinical outcome, recurrence and risk for hemorrhagic transformation are still in quarry. The European Heart Rhythm Association recommends the usage of anticoagulants after 3–4 days after a mild stroke, 6 days after moderate stroke and 12 days after a severe stroke.

Case presentation

In our case report, we present two patients who started full therapeutic anticoagulation of low molecular weight heparin from the first day after moderate ischemic stroke, warfarin was added later guided by INR and discharged on oral anticoagulants for associated AF. They improved clinically with improved motor function for both upper and lower limbs, sensation and gaze without any complication followed by serial CT.

Clinical discussion and conclusion

As a result of this case report, clinical improvement has not been associated with hemorrhagic sequelae of anticoagulant administration on the first day. At this point, we recommend conducting a trial to study the effect of early application of anticoagulants from the first day on clinical outcome, recurrence, and hemorrhagic transfusion of stroke.

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The hemorrhagic transformation of ischemic stroke is one of the most traumatic outcomes.

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Therefore, determining the optimal time to apply anticoagulants.

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And their impact on clinical outcome, recurrence, and hemorrhagic transformation remains challenging.

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According to this case report, there are no hemorrhagic sequelae associated with the first day of anticoagulant therapy.

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Anticoagulation recommendations should therefore be supported or rejected based on more research.

Antithrombotic dilemmas in stroke medicine: new data, unsolved challenges

Antithrombotic therapy is a key element of secondary prevention in patients who have had an ischaemic stroke or transient ischaemic attack. However, its use in clinical practice is not always straightforward. This review provides an update on certain difficult scenarios in antithrombotic management, with a focus on recent clinical trials and large observational studies. We discuss the approach to patients with an indication for antithrombotic treatment who also have clinical or radiological evidence of previous intracranial bleeding, patients with indications for both anticoagulant and antiplatelet treatment, and patients in whom antithrombotic treatment fails to prevent stroke. We also review the timing of anticoagulation initiation after cardioembolic stroke, and the use of antithrombotics in patients with asymptomatic cerebrovascular disease. Despite a wealth of new evidence, numerous uncertainties remain and we highlight ongoing trials addressing these.

Hypertension and Arrhythmias: A Clinical Overview of the Pathophysiology-Driven Management of Cardiac Arrhythmias in Hypertensive Patients

Because of demographic aging, the prevalence of arterial hypertension (HTN) and cardiac arrhythmias, namely atrial fibrillation (AF), is progressively increasing. Not only are these clinical entities strongly connected, but, acting with a synergistic effect, their association may cause a worse clinical outcome in patients already at risk of ischemic and/or haemorrhagic stroke and, consequently, disability and death. Despite the well-known association between HTN and AF, several pathogenetic mechanisms underlying the higher risk of AF in hypertensive patients are still incompletely known. Although several trials reported the overall clinical benefit of renin–angiotensin–aldosterone inhibitors in reducing incident AF in HTN, the role of this class of drugs is greatly reduced when AF diagnosis is already established, thus hinting at the urgent need for primary prevention measures to reduce AF occurrence in these patients. Through a thorough review of the available literature in the field, we investigated the basic mechanisms through which HTN is believed to promote AF, summarising the evidence supporting a pathophysiology-driven approach to prevent this arrhythmia in hypertensive patients, including those suffering from primary aldosteronism, a non-negligible and under-recognised cause of secondary HTN. Finally, in the hazy scenario of AF screening in hypertensive patients, we reviewed which patients should be screened, by which modality, and who should be offered oral anticoagulation for stroke prevention.

Rationale, Design and Methods of the Prospective Record of the Use of Dabigatran in Patients with Acute Stroke or TIA (PRODAST) Study

Background

The optimal timing of anticoagulation following acute ischaemic stroke or TIA in patients with atrial fibrillation (AF) is a frequent challenge. Early initiation of anticoagulation can reduce the risk for recurrent ischaemic events, but may lead to an increased risk for intracerebral haemorrhage.

Aim

The Prospective Record of the Use of Dabigatran in Patients with Acute Stroke or TIA (PRODAST) study was initiated to investigate outcome events under antithrombotic therapy after ischaemic stroke or TIA in patients with AF. The main objective is to compare the three-month rates of major haemorrhagic events between early (≤ 7 days) versus late (> 7 days) administration of dabigatran or treatment with vitamin-K antagonists started at any time. Occurrences of ischaemic and major haemorrhagic events will be evaluated to determine the optimal time point for initiation or resumption of anticoagulation.

Design and Methods

PRODAST is a prospective, multicenter, observational, non-interventional post-authorization safety study. 10,000 patients with recent (≤ 1 week from index event) ischaemic stroke or TIA and non-valvular AF were recruited at 86 German sites starting in July 2015. The observational plan includes a baseline visit, documentation of data during hospitalization and a telephone-based, central follow-up at three months after the index event. The primary endpoint is the major bleeding rate within three months. Secondary endpoints include rates of recurrent ischaemic or haemorrhagic stroke, TIA, systemic embolism, myocardial infarction and death.

Summary

PRODAST will provide important real-world data on safety and efficacy of antithrombotic therapy after acute stroke and TIA in patients with AF.

Optimal timing of anticoagulation after acute ischemic stroke with atrial fibrillation (OPTIMAS): Protocol for a randomized controlled trial

RATIONALE

Atrial fibrillation causes one-fifth of ischemic strokes, with a high risk of early recurrence. Although long-term anticoagulation is highly effective for stroke prevention in atrial fibrillation, initiation after stroke is usually delayed by concerns over intracranial hemorrhage risk. Direct oral anticoagulants offer a significantly lower risk of intracranial hemorrhage than other anticoagulants, potentially allowing earlier anticoagulation and prevention of recurrence, but the safety and efficacy of this approach has not been established.

AIM

Optimal timing of anticoagulation after acute ischemic stroke with atrial fibrillation (OPTIMAS) will investigate whether early treatment with a direct oral anticoagulant, within four days of stroke onset, is as effective or better than delayed initiation, 7 to 14 days from onset, in atrial fibrillation patients with acute ischemic stroke.

METHODS AND DESIGN

OPTIMAS is a multicenter randomized controlled trial with blinded outcome adjudication. Participants with acute ischemic stroke and atrial fibrillation eligible for anticoagulation with a direct oral anticoagulant are randomized 1:1 to early or delayed initiation. As of December 2021, 88 centers in the United Kingdom have opened.

STUDY OUTCOMES

The primary outcome is a composite of recurrent stroke (ischemic stroke or symptomatic intracranial hemorrhage) and systemic arterial embolism within 90 days. Secondary outcomes include major bleeding, functional status, anticoagulant adherence, quality of life, health and social care resource use, and length of hospital stay.

SAMPLE SIZE TARGET

A total of 3478 participants assuming event rates of 11.5% in the control arm and 8% in the intervention arm, 90% power and 5% alpha. We will follow a non-inferiority gatekeeper analysis approach with a non-inferiority margin of 2 percentage points.

DISCUSSION

OPTIMAS aims to provide high-quality evidence on the safety and efficacy of early direct oral anticoagulant initiation after atrial fibrillation-associated ischemic stroke.Trial registrations: ISRCTN: 17896007; ClinicalTrials.gov: NCT03759938.

Overview of Acute Ischemic Stroke Evaluation and Management

Stroke is a major contributor to death and disability worldwide. Prior to modern therapy, post-stroke mortality was approximately 10% in the acute period, with nearly one-half of the patients developing moderate-to-severe disability. The most fundamental aspect of acute stroke management is "time is brain". In acute ischemic stroke, the primary therapeutic goal of reperfusion therapy, including intravenous recombinant tissue plasminogen activator (IV TPA) and/or endovascular thrombectomy, is the rapid restoration of cerebral blood flow to the salvageable ischemic brain tissue at risk for cerebral infarction. Several landmark endovascular thrombectomy trials were found to be of benefit in select patients with acute stroke caused by occlusion of the proximal anterior circulation, which has led to a paradigm shift in the management of acute ischemic strokes. In this modern era of acute stroke care, more patients will survive with varying degrees of disability post-stroke. A comprehensive stroke rehabilitation program is critical to optimize post-stroke outcomes. Understanding the natural history of stroke recovery, and adapting a multidisciplinary approach, will lead to improved chances for successful rehabilitation. In this article, we provide an overview on the evaluation and the current advances in the management of acute ischemic stroke, starting in the prehospital setting and in the emergency department, followed by post-acute stroke hospital management and rehabilitation.

Diastolic blood pressure achieved at target systolic blood pressure (120-140 mm Hg) and dabigatran-related bleeding in patients with nonvalvular atrial fibrillation: A real-world study

Objective:

Elevated systolic blood pressure (SBP) can significantly increase the bleeding risk in patients with atrial fibrillation (AF). However, it is unclear whether elevated diastolic blood pressure (DBP), in the presence of well-controlled SBP is also associated with bleeding. Therefore, we aimed to examine the specific relationship between DBP and bleeding in patients with AF treated with anticoagulants and had well-controlled SBP.

Methods:

We analyzed data from 542 of 929 patients with nonvalvular AF (NVAF) treated with dabigatran from the Monitor System for the Safety of Dabigatran Treatment study (MISSION-AF) who had a SBP of 120–140 mm Hg at the time of enrollment. The association between DBP and bleeding was analyzed using multivariate logistic regression and smooth curve fitting (penalized spline method). Threshold saturation effect analysis was used to show the nonlinear relationship between DBP and bleeding.

Results:

After 3 months of follow-up, 49 bleeding events occurred. Compared with participants with DBP <80 mm Hg, those with DBP ≥80 mm Hg had a 118% higher bleeding risk [hazard ratio (HR): 2.18; 95% confidence interval (CI): 1.19, 3.98; p<0.05]. The smooth curve showed a nonlinear relationship between DBP and bleeding risk, and the inflection point of DBP was 80 mm Hg. When DBP was ≥80 mm Hg, the bleeding risk increased by 59% (HR: 1.59; 95% CI: 1.16, 2.19; p<0.05) for every 5 mm Hg increase in DBP.

Conclusion:

Upon achieving an optimal SBP (120–140 mm Hg), a higher DBP might be associated with a higher bleeding risk in patients with NVAF treated with dabigatran.

Extent of white matter lesion is associated with early hemorrhagic transformation in acute ischemic stroke related to atrial fibrillation

BACKGROUND

Hemorrhagic transformation (HT) after stroke, related to atrial fibrillation (AF), is a frequent complication, and it can be associated with a delay in the (re-)initiation of oral anticoagulation therapy. We investigated the effect of the presence and severity of white matter disease (WMD) on early HT after stroke related to AF.

METHODS

A consecutive series of patients with recent (<4 weeks) ischemic stroke and AF, treated at the Hyper Acute Stroke Unit of the Imperial College London between 2010 and 2017, were enrolled. Patients with brain MRI performed 24-72 h from stroke onset and not yet started on anticoagulant treatment were included. WMD was graded using the Fazekas score.

RESULTS

Among the 441 patients eligible for the analysis, 91 (20.6%) had any HT. Patients with and without HT showed similar clinical characteristics. Patients with HT had a larger diffusion-weighted imaging (DWI) infarct volume compared to patients without HT (p < .001) and significant difference in the distribution of the Fazekas score (p = .001). On multivariable analysis, HT was independently associated with increasing DWI infarct volume (odd ratio (OR), 1.03; 95% confidence interval (CI), 1.01-1.05; p < .001), higher Fazekas scores (OR, 1.94; 95% CI, 1.47-2.57; p < .001) and history of previous intracranial hemorrhage (OR, 4.80; 95% CI, 1.11-20.80; p = .036).

CONCLUSIONS

Presence and severity of WMD is associated with increased risk of development of early HT in patients with stroke and AF. Further evidence is needed to provide reliable radiological predictors of the risk of HT in cardioembolic stroke.

[Secondary stroke prevention after TIA or ischemic stroke]

Stroke is one of the main causes of mortality and permanent disability. Secondary prevention of stroke recurrence therefore has a high priority. Secondary prevention of ischemic stroke includes optimization of the lifestyle and diet, treatment of risk factors, such as hypertension, diabetes mellitus and hyperlipidemia, prophylaxis of recurrence with antiplatelet treatment in patients with high vascular risk and anticoagulation in atrial fibrillation. In addition, secondary prevention includes carotid surgery or stenting in selected symptomatic patients and closure of a patent foramen ovale after cryptogenic stroke.

Primary and Secondary Prevention of Ischemic Stroke and Cerebral Hemorrhage: JACC Focus Seminar

Stroke is a leading cause of permanent disability. Therefore, primary prevention of first stroke and secondary prevention of recurrent stroke are a high priority. Primary prevention of ischemic stroke includes lifestyle modification and diet, treatment of risk factors including hypertension, diabetes mellitus and lipid disorders, antiplatelet therapy for high vascular risk patients, and anticoagulation in atrial fibrillation. Secondary prevention of ischemic stroke includes additional carotid surgery or stenting in selected symptomatic patients, closure of patent foramen ovale after cryptogenic stroke, treatment of insulin resistance, and best medical treatment of intracranial stenosis. The most important preventive strategies in the primary and secondary prevention of cerebral hemorrhage include the treatment of hypertension, reduction in alcohol intake, and occlusion of the left atrial appendage in patients with atrial fibrillation and permanent contraindications for oral anticoagulation.

Acute ischemic stroke management: concepts and controversies.A narrative review

INTRODUCTION

Amongst the 25.7 million survivors and 6.5 million deaths from stroke between 1990 and 2013, ischemic strokes accounted for approximately 70% and 50% of the cases, respectively. With patients still suffering from complications and stroke recurrence, more questions have been raised as to how we can better improve patient management.

AREAS COVERED

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement and Newcastle-Ottawa Scale (NOS) were adopted to ensure a comprehensive inclusion of quality literature from various sources. PubMed and Embase were searched for evidence on thrombolysis, mechanical thrombectomy, artificial intelligence (AI), antiplatelet therapy, anticoagulation and hypertension management.

EXPERT OPINION

The directions of future research in these areas are dependent on the current level of validation. Endovascular therapy and applications of AI are relatively new compared to the other areas discussed in this review. As such, future studies need to focus on validating their efficacy. As for thrombolysis, antiplatelet and anticoagulation therapy, their efficacy has been well-established and future research efforts should be directed toward adjusting its use according to patient-specific factors, starting with factors with the most clinical relevance and prevalence.

Early initiation of direct anticoagulation after stroke in patients with atrial fibrillation

BACKGROUND AND PURPOSE

The safety of early initiation of anticoagulant therapy in patients with ischaemic stroke related to atrial fibrillation (AF) is unknown. We investigated the safety of early initiation of direct oral anticoagulants (DOACs), vitamin K antagonists (VKAs) or no anticoagulation.

METHODS

This observational, retrospective, single-centre study included consecutive patients with recent (<4 weeks) ischaemic stroke and AF. The primary outcome was the rate of major (intracranial and extracranial) bleeding in patients on different treatment schemes, i.e. DOACs, VKAs and not anticoagulated. We also investigated the rate of ischaemic cerebrovascular events and mortality.

RESULTS

We included 959 consecutive patients with AF and ischaemic stroke followed up for an average of 16.1 days after the index event. A total of 559 out of 959 patients (58.3%) were anticoagulated with either VKAs (n = 259) or DOACs (n = 300). Anticoagulation was started after a mean of 7 ± 9.4 days in the DOAC group and 11.9 ± 19.7 days in the VKA group. Early initiation of any anticoagulant was not associated with an increased risk of any major bleeding [odds ratio (OR), 0.49; 95% confidence intervals (CI), 0.21-1.16] and in particular of intracranial bleeding (OR, 0.47; 95% CI, 0.17-1.29; P = 0.143) compared with no anticoagulation. In contrast to VKAs (OR, 0.78; 95% CI, 0.28-2.13), treatment with DOACs (OR, 0.32; 95% CI, 0.10-0.96) reduced the rate of major bleeding compared with no anticoagulation. Early recurrences of ischaemic stroke did not differ significantly among the three groups.

CONCLUSIONS

Starting DOACs within a mean of 7 days after stroke appeared to be safe. Randomized controlled studies are needed to establish the added efficacy of starting anticoagulation early after stroke.

Ischemic stroke and non-valvular atrial fibrillation: When to introduce anticoagulant therapy?

About 20 to 30% of ischemic strokes are related to non-valvular atrial fibrillation. This type of situation is particularly at risk for both recurrence of the ischemic event and the hemorrhagic transformation of this stroke. The timing of the introduction or going back to the anticoagulant therapy in these patients remains a difficult issue, with a complex benefit-risk balance that needs to be assessed. Randomized controlled studies are lacking and current recommendations do not allow for clear decision making. The administration of a curative anticoagulant within 72 hours after the event is not recommended in the absence of demonstrated efficacy in preventing recurrence at this stage and because of the risk of intracerebral hemorrhage. This attitude can nevertheless be qualified by a transient accident or ischemic accident of very small size, and in the absence of any other risk factor for intra- or extra-cerebral hemorrhage. From the 4th day, after an appropriate case by case evaluation, the introduction of anticoagulant would be possible within a time which will remain at the appreciation of the medical teams. If the patient's risk of an intracerebral hemorrhage or general bleeding is transiently increased, it will be preferable to wait at least 2 weeks after the stroke. If this risk persists in the long term, the decision of the administration or not of an anticoagulant will have to be made with a multidisciplinary consultation. Vitamin K antagonists or direct oral anticoagulants may be prescribed as first-line therapy for the prevention of recurrence of ischemic stroke in a non-valvular atrial fibrillation patient. The choice will be based on the clinical and biological data of each patient. Direct oral anticoagulants have not shown superiority in the prevention of ischemic recurrence but open up new prospects for earlier treatment if their lesser risk of bleeding is confirmed after further studies.

Predicting hemorrhagic transformation and its timing from maximum cerebral lesion diameter in nonlacunar ischemic strokes

OBJECTIVES

We performed this retrospective cohort study to establish which factors are mostly indicative of the appearance of hemorrhagic transformation (HT) and of its time course in a sample of nonlacunar ischemic strokes.

MATERIALS AND METHODS

In 402 patients with nonlacunar ischemic stroke (75.0 ± 12.7 years, 192 male), clinical, laboratory, and neuroimaging variables obtained during the first 3 days of hospitalization were compared between patients with and without HT at computer tomography scan.

RESULTS

HT was documented in 129 patients (32.1%), including 36 with parenchymal hematoma (PH), after a median time of 6 days (range 1-27). Many variables were univariately associated with HT, but only 5 of them were confirmed in Cox regression (Hazard Ratio, 95% Confidence Interval): maximum cerebral lesion diameter (CLD) in cm (1.12, 1.06-1.18; p = .0001), hemoglobin in g/dl (1.16, 1.06-1.27; p = .002), blood glucose in mmol/L (1.10, 1.03-1.18; p = .007), prior anticoagulant therapy (1.82, 1.10-3.03; p = .02), and edema with mass effect (1.72, 1.08-2.75; p = .02). Thus, the most significant predictor was CLD. The overall risk of HT was minimum for CLD < 2 cm (1.5%), intermediate for CLD ≥ 2 and < 5 cm (22%), and maximum for CLD ≥ 5 cm (58%). The residual probability of having HT decreased progressively over time, and a simple formula is proposed to predict, from CLD in cm, when the probability of HT falls below 10%.

CONCLUSIONS

The main determinant of HT was CLD, a simple quantitative parameter that could prove useful, in particular, in deciding the timing of anticoagulation in cardioembolic stroke patients.

A Narrative Review of Nonvitamin K Antagonist Oral Anticoagulant Use in Secondary Stroke Prevention

The prevalence of atrial fibrillation (AF), the most common cardiac arrhythmia, increases with age, predisposing elderly patients to an increased risk of embolic stroke. With an increasingly aged population the number of people who experience a stroke every year, overall global burden of stroke, and numbers of stroke survivors and related deaths continue to increase. Anticoagulation with vitamin K antagonists (VKAs) reduces the risk of ischemic stroke in patients with AF; however, increased bleeding risk is well documented, particularly in the elderly. Consequently, VKAs have been underused in the elderly. Alternative anticoagulants may offer a safer choice, particularly in patients who have experienced previous stroke. The aim of this narrative review is to examine available evidence for the effective treatment of patients with AF and previous cerebral vascular events with non-VKA oral anticoagulants, including the most appropriate time to start or reinitiate treatment after a stroke, systemic embolism, or clinically relevant bleed. For patients with AF treated with oral anticoagulants it is important to balance increased protection against future stroke/systemic embolism and reduced risk of major bleeding events. For patients with AF who have previously experienced a cerebrovascular event, the use of oral anticoagulants alone also appears more effective than low-molecular weight heparin (LMWH) alone or LMWH followed by oral anticoagulants. Available data suggest that significant reduction in stroke, symptomatic cerebral bleeding, and major extracranial bleeding within 90 days from acute stroke can be achieved if oral anticoagulation is initiated at 4-14 days from stroke onset.

Fitting the right non-vitamin K antagonist oral anticoagulant to the right patient with non-valvular atrial fibrillation: an evidence-based choice

Atrial fibrillation (AF) is the most prevalent arrhythmia and is associated with an increased risk of ischemic stroke (IS) and systemic embolism (SE). Stroke prevention is a key element for the overall management of AF patients. The non-vitamin K antagonist oral anticoagulants (NOACs), such as dabigatran, rivaroxaban, apixaban and edoxaban, are at least as effective as warfarin in reducing IS/SE with a lower rate of major bleeding. Various analyses from the large Phase III randomized trials demonstrated different efficacy and safety of NOACs in specific subgroups of patients. The randomized trials are supplemented by effectiveness and safety data from real-world observational cohorts following the availability of these drugs for use in everyday clinical practice. Given the clinical heterogeneity of AF patients, the available data from trials and real-world studies allow us to fit the right NOAC to the particular patient's characteristics, with the aim of optimizing outcomes for the individual patient. This review article aims to provide a summary of the evidence on the performance of NOACs in AF patients with specific clinical characteristics. Evidence-based suggestions are presented to provide a simple and viable strategy for clinicians for the choice of a particular NOAC. KEY MESSAGE Given the different performance of the new-oral anticoagulants in patients with the different clinical situation, evidence-based choice of fitting the right new-oral anticoagulants to the patients is provided in this review article.

Anticoagulation Resumption After Intracerebral Hemorrhage

Purpose of review

Decision-making on resuming oral anticoagulant (OAC) after intracerebral hemorrhage (ICH) evokes significant debate among clinicians. Such patients have been excluded from randomized clinical trials. This review article provides a comprehensive summary of the evidence on anticoagulation resumption after ICH.

Recent findings

OAC resumption does not increase the risk of recurrent ICH and can also reduce the risk of all-cause mortality. OAC cessation exposes patients to a significantly higher risk of thromboembolism, which could be reduced by resumption. The optimal timing of anticoagulation resumption after ICH is still unknown. Both early (< 2 weeks) and late (> 4 weeks) resumption should be reached only after very careful assessment of risks for ICH recurrence and thromboembolism. The introduction of new oral anticoagulants and other interventions, such as left atrial appendage closure, has provided some patients with more alternatives.

Summary

Given the lack of high-quality evidence to guide clinical decision-making, clinicians must carefully balance the risks of thromboembolism and recurrent ICH in individual patients. We propose a management approach which would facilitate the decision-making process on whether anticoagulation is appropriate, as well as when and how to restart anticoagulation after ICH.

Early Recurrence and Major Bleeding in Patients With Acute Ischemic Stroke and Atrial Fibrillation Treated With Non-Vitamin-K Oral Anticoagulants (RAF-NOACs) Study

BACKGROUND

The optimal timing to administer non-vitamin K oral anticoagulants (NOACs) in patients with acute ischemic stroke and atrial fibrillation is unclear. This prospective observational multicenter study evaluated the rates of early recurrence and major bleeding (within 90 days) and their timing in patients with acute ischemic stroke and atrial fibrillation who received NOACs for secondary prevention.

METHODS AND RESULTS

Recurrence was defined as the composite of ischemic stroke, transient ischemic attack, and symptomatic systemic embolism, and major bleeding was defined as symptomatic cerebral and major extracranial bleeding. For the analysis, 1127 patients were eligible: 381 (33.8%) were treated with dabigatran, 366 (32.5%) with rivaroxaban, and 380 (33.7%) with apixaban. Patients who received dabigatran were younger and had lower admission National Institutes of Health Stroke Scale score and less commonly had a CHA₂DS₂-VASc score >4 and less reduced renal function. Thirty-two patients (2.8%) had early recurrence, and 27 (2.4%) had major bleeding. The rates of early recurrence and major bleeding were, respectively, 1.8% and 0.5% in patients receiving dabigatran, 1.6% and 2.5% in those receiving rivaroxaban, and 4.0% and 2.9% in those receiving apixaban. Patients who initiated NOACs within 2 days after acute stroke had a composite rate of recurrence and major bleeding of 12.4%; composite rates were 2.1% for those who initiated NOACs between 3 and 14 days and 9.1% for those who initiated >14 days after acute stroke.

CONCLUSIONS

In patients with acute ischemic stroke and atrial fibrillation, treatment with NOACs was associated with a combined 5% rate of ischemic embolic recurrence and severe bleeding within 90 days.

Stroke prevention in atrial fibrillation: Past, present and future

Concepts and our approaches to stroke prevention in atrial fibrillation (AF) have changed markedly over the last decade. There has been an evolution over the approach to stroke and bleeding risk assessment, as well as new treatment options. An increasing awareness of AF has led to calls to improve the detection of and population screening for AF. Stroke and bleeding risk assessment continues to evolve, and the ongoing debate on balance between simplicity and practicality, against precision medicine will continue. In this review article, we provide an overview of past, present and the (likely) future concepts and approaches to stroke prevention in AF. We propose three simple steps (the Birmingham ‘3-step’) that offers a practical management pathway to help streamline and simplify decision-making for stroke prevention in patients with AF.

Note: The review process for this paper was fully handled by Christian Weber, Editor in Chief.

Decision Algorithms for Direct Oral Anticoagulant Use in Patients With Nonvalvular Atrial Fibrillation: A Practical Guide for Neurologists

Direct oral anticoagulants (DOACs) are valid alternative options to vitamin K antagonists due to their limited interactions with drugs or food and the fact that they do not require regular coagulation monitoring. To this regard, recent practice guidelines recommend that DOACs should be considered as first-line anticoagulant therapy for stroke prevention in patients with nonvalvular atrial fibrillation (NVAF). This review (1) outlines current international guidelines for the management of DOACs to prevent stroke in patients with NVAF, (2) outlines indications for elderly patients as well as specific settings including acute coronary syndromes and intracranial hemorrhage, and (3) offers a practical guide for the use of DOACs in neurological settings.

Prediction of Early Recurrent Thromboembolic Event and Major Bleeding in Patients With Acute Stroke and Atrial Fibrillation by a Risk Stratification Schema: The ALESSA Score Study

BACKGROUND AND PURPOSES

This study was designed to derive and validate a score to predict early ischemic events and major bleedings after an acute ischemic stroke in patients with atrial fibrillation.

METHODS

The derivation cohort consisted of 854 patients with acute ischemic stroke and atrial fibrillation included in prospective series between January 2012 and March 2014. Older age (hazard ratio 1.06 for each additional year; 95% confidence interval, 1.00-1.11) and severe atrial enlargement (hazard ratio, 2.05; 95% confidence interval, 1.08-2.87) were predictors for ischemic outcome events (stroke, transient ischemic attack, and systemic embolism) at 90 days from acute stroke. Small lesions (≤1.5 cm) were inversely correlated with both major bleeding (hazard ratio, 0.39; P=0.03) and ischemic outcome events (hazard ratio, 0.55; 95% confidence interval, 0.30-1.00). We assigned to age ≥80 years 2 points and between 70 and 79 years 1 point; ischemic index lesion >1.5 cm, 1 point; severe atrial enlargement, 1 point (ALESSA score). A logistic regression with the receiver-operating characteristic graph procedure (C statistic) showed an area under the curve of 0.697 (0.632-0.763; P=0.0001) for ischemic outcome events and 0.585 (0.493-0.678; P=0.10) for major bleedings.

RESULTS

The validation cohort consisted of 994 patients included in prospective series between April 2014 and June 2016. Logistic regression with the receiver-operating characteristic graph procedure showed an area under the curve of 0.646 (0.529-0.763; P=0.009) for ischemic outcome events and 0.407 (0.275-0.540; P=0.14) for hemorrhagic outcome events.

CONCLUSIONS

In acute stroke patients with atrial fibrillation, high ALESSA scores were associated with a high risk of ischemic events but not of major bleedings.