Aetiology, secondary prevention strategies and outcomes of ischaemic stroke despite oral anticoagulant therapy in patients with atrial fibrillation

Recurrent Ischemic Stroke in Patients With Atrial Fibrillation While Receiving Oral Anticoagulants

Importance

Patients with atrial fibrillation (AF) can have an ischemic stroke (IS) despite oral anticoagulant (OAC) treatment. Knowledge regarding the association between OAC discontinuation and the subsequent risk of recurrent IS in patients with AF is limited.

Objectives

To determine the risk of recurrent IS in patients with AF receiving OAC and to evaluate the association between OAC discontinuation and the risk of recurrent IS.

Design, Setting, and Participants

This is a nationwide cohort study of patients aged 50 years or older in Denmark who had AF and an IS (entry IS) and were initiating or restarting subsequent OAC treatment after being discharged between January 2014 and December 2021. Patients were followed up for recurrent IS until June 2022. Within this study cohort, a nested case-control analysis was performed in which patients with recurrent IS were matched to patients receiving OAC who had not yet experienced a stroke. Data were analyzed from May 25, 2023, to April 18, 2024.

Exposure

Use of OAC at the time of recurrent IS or the equivalent date in matched controls based on redeemed prescriptions.

Main Outcomes and Measures

The primary outcome was recurrent IS. Crude and adjusted cumulative incidences of recurrent IS and all-cause mortality were calculated in cohort analyses, and adjusted odds ratios (aORs) were determined for recurrent IS associated with OAC discontinuation in nested case-control analyses.

Results

The study cohort included 8119 patients (4392 [54.1%] male; mean [SD] age, 78.4 [9.6] years; median (IQR) CHA2DS2-VASc score, 4.0 [3.0-5.0]). Over a mean (SD) follow-up of 2.9 (2.2) years, 663 patients had a recurrent IS, of whom 533 (80.4%) were receiving OAC at the time of their recurrent IS. The crude cumulative incidence of recurrent IS at 1 year was 4.3% (95% CI, 5.9%-7.1%), and the crude cumulative incidence of all-cause mortality was 15.4% (95% CI, 14.7%-16.2%). Adjusted analysis showed similar results. Patients who discontinued OACs had a higher risk of recurrent IS (89 cases [13.4%], 180 controls [6.8%]; aOR, 2.13; 95% CI, 1.57-2.89) compared with patients still receiving OAC.

Conclusions and Relevance

The risks of recurrent IS and mortality were high in patients with AF despite secondary prevention with OAC, and OAC discontinuation doubled the risk of recurrent IS compared with patients who continued OAC. This finding highlights the importance of OAC continuation and the need for improved secondary stroke prevention in patients with AF.

Left atrial appendage closure in patients with atrial fibrillation and acute ischaemic stroke despite anticoagulation

BACKGROUND

The occurrence of acute ischaemic stroke (AIS) while using oral anticoagulants (OAC) is an increasingly recognised problem among nonvalvular atrial fibrillation (NVAF) patients. We aimed to elucidate the potential role of left atrial appendage closure (LAAC) for stroke prevention in patients with AIS despite OAC use (AIS-despite-OAC).

METHODS

We retrospectively collected baseline and follow-up data from consecutive NVAF patients who had AIS-despite-OAC and subsequently underwent endovascular LAAC, between January 2015 and October 2021. The primary outcome measure was the occurrence of AIS after LAAC, and the safety outcome was symptomatic intracerebral haemorrhage (ICH).

RESULTS

29 patients had LAAC specifically because of AIS-despite-OAC. The mean age at the time of the procedure was 73.4±8.7, 13 were female (44.82%). The mean CHA2DS2-VASc score was 5.96±1.32, with an expected AIS risk of 8.44 per 100 patient-years. 14 patients (48%) had two or more past AIS-despite-OAC. After LAAC, 27 patients (93.10%) were discharged on OAC which was discontinued in 17 (58.62%) after transoesophageal echocardiogram at 6 weeks. Over a mean of 1.75±1.0 years follow-up after LAAC, one patient had an AIS (incidence rate (IR) 1.97 per 100 patient-years). One patient with severe cerebral microangiopathy had a small ICH while on direct OAC and antiplatelet 647 days after LAAC.

CONCLUSIONS

LAAC in AIS-despite-OAC patients demonstrated a low annual AIS recurrence rate in our cohort (1.97%) compared with the expected IR based on their CHA2DS2-VASc scores (8.44%) and to recent large series of AIS-despite-OAC patients treated with OAC/aspirin only (5.3%-8.9%). These hypothesis-generating findings support randomised trials of LAAC in AIS-despite-OAC patients.

Left Atrial Appendage Occlusion in Patients With Anticoagulation Failure vs Anticoagulation Contraindication

BACKGROUND

Left atrial appendage occlusion (LAAO) provides mechanical cardioembolic protection for atrial fibrillation (AF) patients who cannot use oral anticoagulation therapy (OAT). Patients with a thrombotic event despite OAT are at high risk for recurrence and may also benefit from LAAO.

OBJECTIVES

This study sought to investigate the efficacy of LAAO in AF patients with a thrombotic event on OAT compared to: 1) LAAO in AF patients with a contraindication for OAT; and 2) historical data.

METHODS

The international LAAO after stroke despite oral anticoagulation (STR-OAC LAAO) collaboration included patients who underwent LAAO because of thrombotic events on OAT. This cohort underwent propensity score matching and was compared to the EWOLUTION (Evaluating Real-Life Clinical Outcomes in Atrial Fibrillation Patients Receiving the WATCHMAN Left Atrial Appendage Closure Technology) registry, which represents patients who underwent LAAO because of OAT contraindications. The primary outcome was ischemic stroke. Event rates were compared between cohorts and with historical data without OAT, yielding relative risk reductions based on risk scores.

RESULTS

Analysis of 438 matched pairs revealed no significant difference in the ischemic stroke rate between the STR-OAC LAAO and EWOLUTION cohorts (2.5% vs 1.9%; HR: 1.37; 95% CI: 0.72-2.61). STR-OAC LAAO patients exhibited a higher thromboembolic risk (HR: 1.71; 95% CI: 1.04-2.83) but lower bleeding risk (HR: 0.39; 95% CI: 0.18-0.88) compared to EWOLUTION patients. The mortality rate was slightly higher in EWOLUTION (4.3% vs 6.9%; log-rank P = 0.028). Relative risk reductions for ischemic stroke were 70% and 78% in STR-OAC LAAO and EWOLUTION, respectively, compared to historical data without OAT.

CONCLUSIONS

LAAO in patients with a thrombotic event on OAT demonstrated comparable stroke rates to the OAT contraindicated population in EWOLUTION. The thromboembolic event rate was higher and the bleeding rate lower, reflecting the intrinsically different risk profile of both populations. Until randomized trials are available, LAAO may be considered in patients with an ischemic event on OAT.

Relationship between electronically monitored adherence to direct oral anticoagulants and ischemic or hemorrhagic events after an initial ischemic stroke-A case control study

BACKGROUND

Patients with atrial fibrillation (AF) have a high risk for recurrent clinical events after an ischemic stroke. Direct oral anticoagulants (DOAC) are prescribed for secondary prevention. Adherence to DOAC is crucial mainly because of their short elimination half-life. Non-adherence to DOAC can negatively impact patients' outcomes. The relationship between (non-)adherence and recurrent clinical events is unknown in AF patients after initial stroke. We investigated adherence to DOAC in stroke survivors with AF who were included in the MAAESTRO study at the University Hospital Basel, Switzerland, between 2008 and 2022.

METHODS

This study is a secondary analysis of data from MAAESTRO with a matched nested case-control design and 1:2 ratio. DOAC intake was measured with a small electronic device (Time4MedTM). We defined two arbitrary intervals of 17 days and 95 days as the longest time spans with electronic monitoring data per patient to maximize the number of participants with adequate amount of observation time available for analysis. Taking and timing adherence were calculated retrospectively i.e., prior to the recurrent event for cases. Trendline analysis of adherence over 95 days was calculated. Linear regression analysis was performed after adjusting for the co-variables age and daily pill burden. Sensitivity analysis was performed with controls for intervals in the reverse direction (prospectively).

RESULTS

We analyzed 11 cases and 22 matched controls (mean age: 75.9 ± 9.2 years vs. 73.1 ± 8.4 years; n.s.) with similar stroke characteristics (NIHSS, mRS, MoCA) and 36.4% women in each group. Mean adherence values were high and similar between cases and controls (95 days taking: 87.0 ± 18.9% (cases) vs. 90.8 ± 9.8% (controls), n.s.; similar values for timing adherence). Six hemorrhagic and five ischemic events had occurred. Compared to controls, a significantly higher 95 days taking adherence was observed for hemorrhagic events (96.0 ± 5.0% (cases) vs. 88.1 ± 11.5% (controls); p<0.01) and a significantly lower 95 days taking adherence was observed for ischemic events (75.7 ± 24.8% (cases) vs. 94.2 ± 6.2% (controls), p = 0.024). Values for timing adherence were similar. A non-significant downward linear trend of adherence was observed over 95 days independently of the clinical events. The sensitivity analysis showed that the direction of the interval had negligible impact on the 95 days adherence.

CONCLUSION

Because recurrent ischemic events after an AF-related stroke were associated with low adherence to DOAC <76%, adherence enhancing interventions seem crucial in anticoagulated AF-patients. However, AF-patients with high adherence might benefit from a regular re-assessment of the bleeding risk as hemorrhagic complications were associated with adherence to DOAC >96%.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03344146.

Secondary stroke prevention in people with atrial fibrillation: treatments and trials

Atrial fibrillation is one of the most common cardiac arrhythmias and is a major cause of ischaemic stroke. Recent findings indicate the importance of atrial fibrillation burden (device-detected, subclinical, or paroxysmal and persistent or permanent) and whether atrial fibrillation was known before stroke onset or diagnosed after stroke for the risk of recurrence. Secondary prevention in patients with atrial fibrillation and stroke aims to reduce the risk of recurrent ischaemic stroke. Findings from randomised controlled trials assessing the optimal timing to introduce direct oral anticoagulant therapy after a stroke show that early start (ie, within 48 h for minor to moderate strokes and within 4-5 days for large strokes) seems safe and could reduce the risk of early recurrence. Other promising developments regarding early rhythm control, left atrial appendage occlusion, and novel factor XI inhibitor oral anticoagulants suggest that these therapies have the potential to further reduce the risk of stroke. Secondary prevention strategies in patients with atrial fibrillation who have a stroke despite oral anticoagulation therapy is an unmet medical need. Research advances suggest a heterogeneous spectrum of causes, and ongoing trials are investigating new approaches for secondary prevention in this vulnerable patient group. In patients with atrial fibrillation and a history of intracerebral haemorrhage, the latest data from randomised controlled trials on stroke prevention shows that oral anticoagulation reduces the risk of ischaemic stroke but more data are needed to define the safety profile.

Practical guide on left atrial appendage closure for the non-implanting physician: an international consensus paper

A significant proportion of patients who suffer from atrial fibrillation (AF) and are in need of thromboembolic protection are not treated with oral anticoagulation or discontinue this treatment shortly after its initiation. This undertreatment has not improved sufficiently despite the availability of direct oral anticoagulants which are associated with less major bleeding than vitamin K antagonists. Multiple reasons account for this, including bleeding events or ischaemic strokes whilst on anticoagulation, a serious risk of bleeding events, poor treatment compliance despite best educational attempts, or aversion to drug therapy. An alternative interventional therapy, which is not associated with long-term bleeding and is as effective as vitamin K anticoagulation, was introduced over 20 years ago. Because of significant improvements in procedural safety over the years, left atrial appendage closure, predominantly achieved using a catheter-based, device implantation approach, is increasingly favoured for the prevention of thromboembolic events in patients who cannot achieve effective anticoagulation. This management strategy is well known to the interventional cardiologist/electrophysiologist but is not more widely appreciated within cardiology or internal medicine. This article introduces the devices and briefly explains the implantation technique. The indications and device follow-up are more comprehensively described. Almost all physicians who care for adult patients will have many with AF. This practical guide, written within guideline/guidance boundaries, is aimed at those non-implanting physicians who may need to refer patients for consideration of this new therapy, which is becoming increasingly popular.

Acute Ischaemic Stroke in Patients Treated with Direct Oral Anticoagulants: Potential Causes, Clinical Characteristics, and Short-Term Outcomes

Introduction

Direct oral anticoagulants (DOAC) are the first-line treatment for primary and secondary acute ischaemic stroke (AIS) prevention in patients with nonvalvular atrial fibrillation (NVAF), but a significant percentage of patients develop AIS despite being treated with DOAC. As the number of DOAC-treated patients is growing, so is the number of patients with AIS on DOAC. The aim of the study was to assess the incidence of AIS with prestroke DOAC treatment among patients hospitalised in the University Hospital in Kraków, to analyse the clinical characteristics of AIS occurring in patients on DOAC, and to identify potential causes of treatment ineffectiveness in this group.

Materials and Methods

In the study, we included all patients hospitalised in the Department of Neurology of the University Hospital in Kraków within one year (July 2022 to June 2023) with the diagnosis of AIS. The group was divided into two subgroups of patients with and without prestroke DOAC treatment. Based on medical files, we retrospectively analysed the profile of cardiovascular risk factors, stroke severity (assessed with National Institutes of Health Stroke Scale, NIHSS), use of causative stroke treatment and short-term outcomes (defined as NIHSS score, modified Rankin scale (mRS) score at discharge, in-hospital mortality, and secondary intracerebral haemorrhage among patients treated with mechanical thrombectomy, MT). Within the DOAC-treated subgroup, we looked for potential causes of AIS occurring despite DOAC treatment (valvular AF, poor adherence to treatment, underdosing, other prothrombotic conditions, aetiology of stroke other than thromboembolic, and drug-drug interactions).

Results

In the study, we included 768 AIS patients. 109 (14.2%) had a history of prestroke DOAC treatment. A potential cause of DOAC treatment failure was identified in the majority of them (n = 63, 57.8%). Patients with prestroke DOAC treatment had worse functional condition before stroke and higher stroke severity on admission but similar short-term outcomes and similar short-term effects of treatment with MT. DOAC (+) and DOAC (-) patients had different profiles of cardiovascular risk factors and different factors associated with short-term outcome. Conclusions and Clinical Implications. A potential cause of AIS occurring in DOAC-treated patients can be identified in most cases and in many of them prevented.

Changing or Retaining Direct Oral Anticoagulant After Ischemic Stroke Despite Direct Oral Anticoagulant Treatment

BACKGROUND

The optimal antithrombotic strategies for patients with atrial fibrillation who experience ischemic stroke (IS) despite direct oral anticoagulant (DOAC) therapy remain inconclusive. This study compared outcomes for patients with DOAC treatment failure who changed or retained their prestroke DOAC.

METHODS AND RESULTS

This retrospective cohort study analyzed data from the National Health Insurance Research Database from 2012 to 2020. Patients with atrial fibrillation who experienced IS during DOAC therapy were assigned to either (1) the DOAC-change group: changing prestroke DOAC or (2) the DOAC-retain group: retaining prestroke DOAC. The primary outcome was a composite of recurrent IS and transient ischemic attack. The secondary outcomes included intracranial hemorrhage, major bleeding, systemic thromboembolism, and all-cause death. Propensity score-based inverse probability of treatment weighting was applied to balance the baseline characteristics between the DOAC-change and DOAC-retain groups. The Cox proportional hazards model compared the risk of outcomes between the 2 groups. In total, 1979 patients were enrolled (609 DOAC-change patients and 1370 DOAC-retain patients). The incidence rates of recurrent IS or transient ischemic attack were 7.20 and 6.56 per 100 person-years in the DOAC-change and DOAC-retain groups, respectively (hazard ratio [HR], 1.07 [95% CI, 0.87-1.30]). A nonsignificantly higher incidence rate of intracranial hemorrhage was observed in the DOAC-change group compared with the DOAC-retain group (0.75 versus 0.53 per 100-person-years; HR, 1.49 [95% CI, 0.78-2.83]). The systemic thromboembolism, major bleeding, and death rates were comparable between the DOAC-change and DOAC-retain groups.

CONCLUSIONS

Changing prestroke DOAC does not reduce the risk of recurrent cerebral ischemia in patients with atrial fibrillation who develop IS during DOAC therapy. However, future studies should continue to observe the potential trends of increased intracranial hemorrhage risk.

Atrial fibrillation: stroke prevention

Stroke prevention is central to the management of patients with atrial fibrillation (AF) which has moved towards a more holistic or integrative care approach. The published evidence suggests that management of AF patients following such a holistic approach based on the Atrial fibrillation Better Care (ABC) pathway is associated with a lower risk of stroke and adverse events. Risk assessment, re-assessment and use of direct oral anticoagulants (DOACs) are important for stroke prevention in AF. The stroke and bleeding risks of AF patients are not static and should be re-assessed regularly. Bleeding risk assessment is to address and mitigate modifiable bleeding risk factors, and to identify high bleeding risk patients for early review and follow-up. Well-controlled comorbidities and healthy lifestyles also play an important role to achieve a better clinical outcome. Digital health solutions are increasingly relevant in the diagnosis and management of patients with AF, with the potential to improve stroke prevention. In this review, we provide an update on stroke prevention in AF, including importance of holistic management, risk assessment/re-assessment, and stroke prevention for special AF populations. Evidence-based and structured management of AF patients would reduce the risk of stroke and other adverse events.

Characteristics of Ischemic Stroke Despite Oral Anticoagulant Use For Atrial Fibrillation

Oral anticoagulation (OAC) prevents stroke in atrial fibrillation, yet a residual stroke risk remains. In this single-center retrospective analysis of acute ischemic stroke patients despite OAC, suboptimal OAC treatment is common (30%: inappropriate dosing (17%); patient non-adherence (13%)). Other causes of stroke included OAC interruption (14.5%), a competing stroke mechanism (11.0%), and undetermined breakthrough stroke in 44.5%. Overall, easily modifiable causes of ischemic stroke despite OAC are common. Accordingly, strategies to improve treatment compliance, including appropriate dosing along with guideline-based risk factor and periprocedural OAC management, should be emphasized to improve secondary stroke prevention in this patient population.

Development and Validation of a New Nomogram Model for Predicting Acute Ischemic Stroke in Elderly Patients with Non-Valvular Atrial Fibrillation: A Single-Center Cross-Sectional Study

Background and Aims

Non-valvular atrial fibrillation (NVAF) patients face a 3-5 times greater risk of acute ischemic stroke (AIS) compared to those without NVAF. This study aims to establish a novel clinical prediction model for AIS in elderly patients with NVAF by incorporating relevant biomarker indicators.

Methods

A total of 301 individuals diagnosed with NVAF were selected for this investigation at the Third Affiliated Hospital of Anhui Medical University. Based on the presence of AIS, patients were categorized into two groups: the Stroke Cohort and the Non-Stroke Cohort. Predictor screening was performed using the least absolute shrinkage and selection operation (LASSO) regression algorithm. The binary logistic regression equation was applied to fit the model, followed by internal validation using the bootstrap resampling method (1000 times). Receiver operating characteristic (ROC) curve, calibration degree curve plots, and clinical decision curve analysis (DCA) were generated, respectively. Finally, a nomogram was constructed to present the prediction model.

Results

The final results of this study revealed that neutrophil-to-lymphocyte ratio (NLR), red cell distribution width (RDW), lipoprotein(a) (Lp(a)), systolic pressure, history of stroke, hyperlipidemia were independent risk factors for AIS in elderly patients with NVAF (P<0.05). And the high-density lipoprotein cholesterol (HDL-C) was an independent protective factor (P<0.05). By incorporating these indicators, a nomogram prediction model for predicting AIS in elderly patients with NVAF was constructed. Comparative analysis between the nomogram predictive model and CHA2DS2-VASc score revealed that the AUC of the nomogram predictive model surpassed that of the CHA2DS2-VASc score (AUC: 0.881vs 0.850).

Conclusion

NLR, RDW, Lp(a), SP, history of stroke, hyperlipidemia, and HDL-C emerge as independent prognostic factors for acute ischemic stroke in elderly patients with non-valvular atrial fibrillation. The predictive utility of the nomogram model may potentially surpass that of the CHA2DS2-VASc scoring system.

Ischaemic stroke in a patient with non-valvular atrial fibrillation (NVAF) despite non-vitamin K oral anticoagulant (NOAC) therapy

Primary stroke prevention in non-valvular atrial fibrillation (NVAF) is primarily with non-vitamin K oral anticoagulant (NOAC) therapy. However, 20-36% of ischaemic strokes seem to occur in patients with atrial fibrillation while already on anticoagulation. We present a case of an ischaemic stroke in an elderly female in her 70s with medical history significant for hypertension and NVAF. She had a CHA2DS2-VASc score of 3 and was on apixaban for thromboprophylaxis. She presented with neurological deficits consistent with a left middle cerebral artery stroke, confirmed via head imaging; the most likely stroke aetiology was determined to be cardioembolic in the setting of NVAF. She was treated with continuation of her apixaban at the same dosage She displayed improved function, although with residual expressive aphasia at her 2-month neurology follow-up. Cardioembolic ischaemic stroke in NVAF despite current NOAC therapy does not have current management guidelines.

Stroke Prevention in Atrial Fibrillation: Our Current Failures and Required Research

Nonvalvular atrial fibrillation is a common rhythm disorder of middle-aged to older adults that can cause ischemic strokes and systemic embolism. Lifelong use of oral anticoagulants reduces the risk of these ischemic events but increases the risk of major and clinically relevant hemorrhages. These medications also require strict compliance for efficacy, and they have nontrivial failure rates in higher-risk patients. Left atrial appendage closure is a nonpharmacological method to prevent ischemic strokes in atrial fibrillation without the need for lifelong anticoagulant use, but this procedure has the potential for complications and residual embolic events. This workshop of the Roundtable of Academia and Industry for Stroke Prevention discussed future research needed to further decrease the ischemic and hemorrhagic risks among patients with atrial fibrillation. A direct thrombin inhibitor, factor Xa inhibitors, and left atrial appendage closure are FDA-approved approaches whereas factor XIa inhibitors are currently being studied in phase 3 randomized controlled trials for stroke prevention. The benefits, risks, and shortcomings of these treatments and future research required in different high-risk patient populations are reviewed in this consensus statement.

The Impact of Atherosclerotic Burden on Vascular Outcomes in Patients with Stroke and Atrial Fibrillation: The ATHENA study

Introduction: Patients with ischemic stroke (IS) and atrial fibrillation (AF) face a higher risk of recurrent vascular events. This study evaluates the impact of atherosclerotic vascular disease burden across different vascular territories on the risk of vascular events in patients with recent ischemic stroke and AF within 90 days. Patients and Methods: We included patients with IS and AF from the International RAF network in a prospective 90-day follow-up. Atherosclerotic vascular disease was identified by at least one of the following: Symptomatic ischemic heart disease, symptomatic peripheral artery disease, internal carotid stenosis ≥50%, or the presence of plaques in the aorta. The primary outcome was a composite of stroke, transient ischemic attack, systemic embolism, cerebral bleeding, and major extracranial bleeding within 90 days postacute stroke. Patients were categorized into 5 groups based on the number of affected atherosclerotic vascular territories, with those with no atherosclerotic vascular disease as the reference. Kaplan-Meier curves were generated and compared using the log-rank test to determine the predictive value of the number of diseased territories for the risk of events. Data analysis was performed with SPSS/PC Win Package 25.0. Results: Of the 2148 patients (mean age 77.59; 53.86% female), 744 (34.60%) had atherosclerosis. Multivariable analysis revealed that involvement of 3 (hazard ratio [HR] 2.80, 95% confidence interval [CI]: 1.20-6.53) or 4 (HR 6.81, 95% CI: 1.02-36.24) vascular territories was significantly associated with the risk of combined events. Conclusions: In patients with recent ischemic stroke and AF, atherosclerosis across multiple territories correlates with a higher risk of future vascular events.

Oral anticoagulants status after acute ischemic stroke and prognosis in patients with atrial fibrillation

OBJECTIVES

To investigate the oral anticoagulants (OACs) use after acute ischemic stroke (AIS) and prognosis of patients with atrial fibrillation (AF).

METHODS

This was a real-world follow-up research of AIS patients with AF admitted to 5 hospitals in northwestern China. We visited these individuals every 6 months to check the type, dosage of OACs, and to record IS recurrence, bleeding, and death events and modified Rankin Scale (mRS) scores until December 2022. When one of the following occurring first was endpoint: IS recurrence, death or study end. Patients were divided into continuous anticoagulation group and non-continuous anticoagulation group based on whether they continued to take OACs from the moment they were discharged until the endpoint. We further analyzed the association between anticoagulation persistence and outcomes.

RESULTS

Among all 250 patients with OACs indication, 147 patients (58.8 %) received OACs at discharge. Only 37.9 % of patients (39/103) started OACs after discharge. Of the 147 patients treated with OACs, 21.8 % (32/147) discontinued anticoagulation after discharge. 239 of the 250 patients had completed the median 40-month follow-up with 91 patients in continuous anticoagulation group and 148 patients in non-continuous anticoagulation group. In the multivariate COX regression, non-continuous anticoagulation was an independent risk factor for poor prognosis (mRS>2) in AIS patients with AF (1.452[1.011, 2.086], p = 0.043).

CONCLUSIONS

This study revealed an upward trend in the use rate of OACs, but low OACs rates that meet guideline-based criteria and low anticoagulation persistence in AF patients after AIS in the northwestern China. Discontinuous anticoagulation was associated with an increased risk of poor prognosis in these patients.

Direct Oral Anticoagulants in Special Patient Populations

Anticoagulants are a cornerstone of treatment in atrial fibrillation. Nowadays, direct oral anticoagulants (DOACs) are extensively used for this condition in developed countries. However, DOAC treatment may be inappropriate in certain patient populations, such as: patients with chronic kidney disease in whom DOAC concentrations may be dangerously elevated; frail elderly patients with an increased risk of falls; patients with significant drug-drug interactions (DDI) affecting either DOAC concentration or effect; patients at the extremes of body mass in whom an "abnormal" volume of distribution may result in inappropriate drug concentrations; patients with recurrent stroke reflecting an unusually high thromboembolic tendency; and, lastly, patients who experience major hemorrhage on an anticoagulant and in whom continued anticoagulation is deemed necessary. Herein we provide a fictional case-based approach to review the recommendations for the use of DOACs in these special patient populations.

Comparing Efficacy and Safety Between Patients With Atrial Fibrillation Taking Direct Oral Anticoagulants or Warfarin After Direct Oral Anticoagulant Failure

BACKGROUND

An increased risk of recurrent stroke is noted in patients with atrial fibrillation despite direct oral anticoagulant (DOAC) use. We investigated the efficacy and safety of treatment with each of 4 different DOACs or warfarin after DOAC failure.

METHODS AND RESULTS

We retrospectively analyzed patients with atrial fibrillation with ischemic stroke despite DOAC treatment between January 2002 and December 2016. The different outcomes of patients with DOAC failure were compared, including recurrent ischemic stroke, major cardiovascular events, intracranial hemorrhage and subarachnoid hemorrhage, mortality, and net composite outcomes according to switching to different DOACs or vitamin K antagonist after index ischemic stroke. We identified 3759 patients with DOAC failure. A total of 84 patients experienced recurrent ischemic stroke after switching to different oral anticoagulants, with a total follow-up time of 14 years. Using the vitamin K antagonist group as a reference, switching to any of the 4 DOACs was associated with a 69% to 77% reduced risk of major cardiovascular events (adjusted hazard ratio [aHR], 0.25 [95% CI, 0.16-0.39] for apixaban, 0.23 [95% CI, 0.14-0.37] for dabigatran, 0.23 [95% CI, 0.09-0.60] for edoxaban, and 0.31 [95% CI, 0.21-0.45] for rivaroxaban), and a 69% to 83% reduced risk of net composite outcomes (aHR, 0.25 [95% CI, 0.18-0.35] for apixaban, 0.17 [95% CI, 0.11-0.25] for dabigatran, 0.31 [95% CI, 0.17-0.56] for edoxaban, and 0.31 [95% CI, 0.23-0.41] for rivaroxaban).

CONCLUSIONS

In Asian patients with DOAC failure, continuing DOACs after index stroke was associated with fewer undesirable outcomes than switching to a vitamin K antagonist. Alternative pharmacologic and nonpharmacologic strategies warrant investigation.

Characteristics and Mechanism of Acute Ischemic Stroke in NAVF Patients With Prior Oral Anticoagulant Therapy

OBJECTIVES

We aimed to analyze the characteristics and mechanisms of acute ischemic stroke (AIS) in patients with nonvalvular atrial fibrillation (NVAF) who received prior anticoagulant therapy.

METHODS

We retrospectively analyzed the data of patients with NVAF and AIS between January 2016 and December 2021. Patients were divided into non-anticoagulant, adequate anticoagulant, and insufficient anticoagulant groups according to their prior anticoagulant status. Patients with prior anticoagulant therapy were further divided into warfarin and direct oral anticoagulant groups.

RESULTS

A total of 749 patients (661 without anticoagulants, 33 with adequate anticoagulants, and 55 with insufficient anticoagulants) were included. Patients with adequate anticoagulant had a milder National Institute of Health Stroke Scale at presentation ( P =0.001) and discharge ( P =0.003), a higher proportion of Modified Rankin Scale (mRS) ≤2 at discharge ( P =0.011), and lower rates of massive infarction ( P =0.008) than patients without anticoagulant. Compared with the non-anticoagulant group, the proportion of intravenous thrombolysis was significantly lower in the adequate anticoagulant ( P <0.001) and insufficient anticoagulant ( P =0.009) groups. Patients in the adequate anticoagulant group had higher rates of responsible cerebral atherosclerotic stenosis ( P =0.001 and 0.006, respectively) and competing large artery atherosclerotic mechanisms ( P =0.006 and 0.009, respectively) than those in the other 2 groups. Compared with warfarin, direct oral anticoagulant was associated with higher rates of Modified Rankin Scale ≤2 at discharge ( P =0.003).

CONCLUSIONS

Adequate anticoagulant therapy may be associated with milder stroke severity and better outcomes at discharge in patients with NVAF. Competing large artery atherosclerotic mechanisms may be associated with anticoagulant failure in patients with NAVF with prior adequate anticoagulant therapy.

Biomarker, Imaging, and Clinical Factors Associated With Overt and Covert Stroke in Patients With Atrial Fibrillation

BACKGROUND

Atrial fibrillation is a major risk factor for stroke and silent brain infarcts. We studied whether a multimodal approach offers additional insights to the CHA2DS2-VASc score in predicting stroke or new brain infarcts on magnetic resonance imaging (MRI) over a 2-year follow-up.

METHODS

Swiss-AF is a prospective, multicenter cohort study of patients with known atrial fibrillation. We included patients with available brain MRI both at enrollment and 2 years later. The dates of the baseline and follow-up visits ranged from March 2014 to November 2020. The primary outcome was assessed 2 years after baseline and was defined as a composite of clinically identified stroke or any new brain infarct on the 2-year MRI. We compared a multivariable logistic regression model including prespecified clinical, biomarker, and baseline MRI variables to the CHA2DS2-VASc score.

RESULTS

We included 1232 patients, 89.8% of them taking oral anticoagulants. The primary outcome occurred in 78 patients (6.3%). The following baseline variables were included in the final multivariate model and were significantly associated with the primary outcome: white matter lesion volume in milliliters (adjusted odds ratio [aOR], 1.91 [95% CI, 1.45-2.56]), NT-proBNP (N-terminal pro-B-type natriuretic peptide; aOR, 1.75 [95% CI, 1.20-2.63]), GDF-15 (growth differentiation factor-15; aOR, 1.68 [95% CI, 1.11-2.53]), serum creatinine (aOR, 1.50 [95% CI, 1.02-2.22]), IL (interleukin)-6 (aOR, 1.37 [95% CI, 1.00-1.86]), and hFABP (heart-type fatty acid-binding protein; aOR, 0.48 [95% CI, 0.31-0.73]). Overall performance and discrimination of the new model was superior to that of the CHA2DS2-VASc score (C statistic, 0.82 [95% CI, 0.77-0.87] versus 0.64 [95% CI, 0.58-0.70]).

CONCLUSIONS

In patients with atrial fibrillation, a model incorporating white matter lesion volume on baseline MRI and selected blood markers yielded new insights on residual stroke risk despite a high proportion of patients on oral anticoagulants. This may be relevant to develop further preventive measures.

Atrial Fibrillation and Ischemic Stroke despite Oral Anticoagulation

Patients with atrial fibrillation (AF) experiencing ischemic stroke despite oral anticoagulation (OAC), i.e., breakthrough strokes, are not uncommon, and represent an important clinical subgroup in view of the consistently high risk of stroke recurrence and mortality. The understanding of the heterogenous potential mechanism underlying OAC failure is essential in order to implement specific therapeutic measures aimed at reducing the risk of recurrent ischemic stroke. However, due to the incomplete comprehension of this phenomenon and the limited available data, secondary stroke prevention in such high-risk patients represents a clinical dilemma. There are several available strategies to prevent ischemic stroke recurrence in AF patients with breakthrough stroke in the absence of competing causes unrelated to AF, and these include continuation or change in the type of OAC, addition of antiplatelet therapy, left atrial appendage closure, or any combination of the above options. However, due to the limited available data, the latest guidelines do not provide any specific recommendations about which of the above strategies may be preferred. This review describes the incidence, the clinical impact and the potential mechanisms underlying OAC failure in AF patients. Furthermore, the evidence supporting each of the above therapeutic options for secondary stroke prevention and the potential future directions will be discussed.

Management and Prognosis of Acute Stroke in Atrial Fibrillation

Atrial fibrillation (AF) is an important risk factor for ischemic stroke (IS). Oral anticoagulation (OAC) significantly reduces the risk of IS in AF but also increases the risk of systemic bleeding, including intracerebral hemorrhage (ICH). AF-related strokes are associated with greater disability and mortality compared to non-AF strokes. The management of patients with AF-related strokes is challenging, and it involves weighing individual risks and benefits in the acute treatment and preventive strategies of these patients. This review summarizes the current knowledge of the acute management of ischemic and hemorrhagic stroke in patients with AF, and the prognosis and potential implications for management both in the acute and long-term setting.

Ischaemic stroke despite antiplatelet therapy: Causes and outcomes

BACKGROUND

Ischaemic stroke may occur despite antiplatelet therapy (APT). We aimed to investigate frequency, potential causes and outcomes in patients with ischaemic stroke despite APT.

METHODS

In this cohort study, we enrolled patients with imaging-confirmed ischaemic stroke from the Swiss Stroke Registry (01/2014-07/2022). We determined the frequency of prior APT, assessed stroke aetiology (modified TOAST classification) and determined the association of prior APT with unfavourable functional outcome (modified Rankin Scale score 3-6) and recurrent ischaemic stroke at 3 months using regression models.

RESULTS

Among 53,352 patients, 27,484 (51.5%) had no prior antithrombotic treatment, 17,760 (33.3%) were on APT, 7039 (13.2%) on anticoagulation and 1069 (2.0%) were on APT + anticoagulation. In patients with a history of ischaemic stroke/TIA (n = 11,948; 22.4%), 2401 (20.1%) had no prior antithrombotic therapy, 6594 (55.2%) were on APT, 2489 (20.8%) on anticoagulation and 464 (3.9%) on APT + anticoagulation. Amongst patients with ischaemic stroke despite APT, aetiology was large artery atherosclerosis in 19.8% (n = 3416), cardiac embolism in 23.6% (n = 4059), small vessel disease in 11.7% (n = 2011), other causes in 7.4% (n = 1267), more than one cause in 6.3% (n = 1078) and unknown cause in 31.3% (n = 5388). Prior APT was not independently associated with unfavourable outcome (aOR = 1.06; 95% CI: 0.98-1.14; p = 0.135) or death (aOR = 1.10; 95% CI: 0.99-1.21; p = 0.059) at 3-months but with increased odds of recurrent stroke (6.0% vs 4.3%; aOR 1.26; 95% CI: 1.11-1.44; p < 0.001).

CONCLUSIONS

One-third of ischaemic strokes occurred despite APT and 20% of patients with a history of ischaemic stroke had no antithrombotic therapy when having stroke recurrence. Aetiology of breakthrough strokes despite APT is heterogeneous and these patients are at increased risk of recurrent stroke.

The impact of competing stroke etiologies in patients with atrial fibrillation

BACKGROUND

Data on the impact of competing stroke etiologies in stroke patients with atrial fibrillation (AF) are scarce.

METHODS

We used prospectively obtained data from an observational registry (Novel-Oral-Anticoagulants-in-Ischemic-Stroke-Patients-(NOACISP)-LONGTERM) of consecutive AF-stroke patients treated with oral anticoagulants. We compared the frequency of (i) the composite outcome of recurrent ischemic stroke (IS), intracerebral hemorrhage (ICH) or all-cause death as well as (ii) recurrent IS alone among AF-stroke patients with versus without competing stroke etiologies according to the TOAST classification. We performed cox proportional hazards regression modeling adjusted for potential confounders. Furthermore, the etiology of recurrent IS was assessed.

RESULTS

Among 907 patients (median age 81, 45.6% female), 184 patients (20.3%) had competing etiologies, while 723 (79.7%) had cardioembolism as the only plausible etiology. During 1587 patient-years of follow-up, patients with additional large-artery atherosclerosis had higher rates of the composite outcome (adjusted HR [95% CI] 1.64 [1.11, 2.40], p = 0.017) and recurrent IS (aHR 2.96 [1.65, 5.35 ], p < 0.001), compared to patients with cardioembolism as the only plausible etiology. Overall 71 patients had recurrent IS (7.8%) of whom 26.7% had a different etiology than the index IS with large-artery-atherosclerosis (19.7%) being the most common non-cardioembolic cause.

CONCLUSION

In stroke patients with AF, causes other than cardioembolism as competing etiologies were common in index or recurrent IS. Concomitant presence of large-artery-atherosclerosis seems to indicate an increased risk for recurrences suggesting that stroke preventive means might be more effective if they also address competing stroke etiologies in AF-stroke patients.

CLINICAL TRIAL REGISTRATION

NCT03826927.

Risk of recurrent stroke in patients with atrial fibrillation treated with oral anticoagulants alone or in combination with anti-platelet therapy

INTRODUCTION

Ischaemic stroke patients with atrial fibrillation (AF) are at high risk of stroke recurrence despite oral anticoagulation therapy. Patients with cardiovascular comorbidities may take both antiplatelet and oral anticoagulation therapy (OAC/AP). Our study aims to evaluate the safety and efficacy of OAC/AP therapy as secondary prevention in people with AF and ischaemic stroke.

PATIENTS AND METHODS

We performed a post-hoc analysis of pooled individual data from multicenter prospective cohort studies and compared outcomes in the OAC/AP cohort and patients on DOAC/VKA anticoagulation alone (OAC cohort). Primary outcome was a composite of ischaemic stroke, systemic embolism, intracranial bleeding, and major extracranial bleeding, while secondary outcomes were ischaemic and haemorrhagic events considered separately. A multivariable logistic regression analysis was performed to identify independent predictors for outcome events. To compare the risk of outcome events between the two cohorts, the relation between the survival function and the set of explanatory variables were calculated by Cox proportional hazard models and the results were reported as adjusted hazard ratios (HR). Finally another analysis was performed to compare the overall risk of outcome events in both OAC/AP and OAC cohorts after propensity score matching (PSM).

RESULTS

During a mean follow-up time of 7.5 ± 9.1 months (median follow-up time 3.5 months, interquartile range ±3), 2284 stroke patients were on oral anticoagulants and 215 were on combined therapy. The multivariable model demonstrated that the composite outcome is associated with age (OR: 1.03, 95% CI: 1.01-1.04 for each year increase) and concomitant antiplatelet therapy (OR: 2.2, 95% CI: 1.48-3.27), the ischaemic outcome with congestive heart failure (OR: 1.55, 95% CI: 1.02-2.36) and concomitant antiplatelet therapy (OR: 1.93, 95% CI: 1.19-3.13) and the haemorrhagic outcome with age (OR: 1.03, 95% CI: 1.01-1.06 for each year increase), alcoholism (OR: 2.15, 95% CI: 1.06-4.39) and concomitant antiplatelet therapy (OR: 2.22, 95% CI: 1.23-4.02). Cox regression demonstrated a higher rate of the composite outcome (hazard ratio of 1.93 [95% CI, 1.35-2.76]), ischaemic events (HR: 2.05 [95% CI: 1.45-2.87]) and bleeding outcomes (HR: 1.90 [95% CI, 1.06-3.40]) in OAC/AP cohort. After PSM analysis, the composite outcome remained more frequent in people treated with OAC + AP (RR: 1.70 [95% CI, 1.05-2.74]).

DISCUSSION

Secondary prevention with combination of oral anticoagulant and antiplatelet therapy after ischaemic stroke was associated with worse outcomes in our cohort.

CONCLUSION

Further research is needed to improve secondary prevention by investigating the mechanisms of recurrent ischaemic stroke in patients with atrial fibrillation.

Low-to-moderate dose statins improve the functional outcome of acute ischemic stroke with conventional medication treatment

Background

Low-to-moderate dose statins (LMDSs) are more commonly used among Asian acute ischemic stroke (AIS) patients in clinical practice. However, the correlation between the LMDS use and prognosis has not been evaluated in AIS patients with conventional medication treatment alone. This study aimed to investigate the influence of LMDS on the prognosis of AIS patients and how prognosis and potential prognostic factors interact with different statin doses.

Methods

This retrospective cohort study included AIS patients who were admitted within 7 days after symptom onset and received conventional medication treatment alone from November 2019 to November 2020 in the Neurology, Department of West China Hospital, Sichuan University. From a total of 782 initial patients, a final cohort of 327 patients was included in the study. These patients were divided into three groups based on statin doses: non-statin (48 patients), LMDS (152 patients), and high-dose statin (HDS) (127 patients). The follow-up period was 3 months after the onset of stroke and the primary outcome was defined as a modified Rankin scale (mRS) score of 0 to 2 at 3 months, secondary outcomes were hemorrhagic transformation (HT) and death within 3 months. Stratified analysis was also conducted to test the robustness of the relationship between the use of different statin doses and functional outcomes in various subgroups.

Results

Compared with non-statin therapy, both LMDS therapy and HDS therapy were associated with good functional outcomes [odds ratio (OR) =3.68, 95% confidence interval (CI): 1.13-12.01, P=0.0309; OR =3.45, 95% CI: 1.06-11.26, P=0.0402, respectively] and a lower risk of HT (OR =0.30, 95% CI: 0.11-0.86, P=0.0253; OR =0.36, 95% CI: 0.13-0.99, P=0.0488, respectively). However, there was no significant difference in all-cause death within 3 months among the three groups (OR =0.84, 95% CI: 0.29-2.46, P=0.7468; OR =0.76, 95% CI: 0.26-2.22, P=0.6104). Additionally, no significant differences were observed between LMDS therapy and HDS therapy regarding good functional outcomes at 3 months (OR =0.94, 95% CI: 0.50-1.77, P=0.8411) and the occurrence of HT (OR =1.19, 95% CI: 0.47-3.02, P=0.7093). The results of the relationship between different statin doses and 3-month good functional outcome were consistent after interaction tests.

Conclusions

Our findings provide evidence for the benefit and safety of LMDS therapy in AIS patients with medication treatment alone. LMDS therapy is associated with favorable impacts on 3-month functional outcomes and a reduced risk of HT compared to non-statin therapy. There were no significant differences in achieving 3-month good functional outcome, the risk of HT or death within 3 months were observed between LMDS and HDS therapy in our study. Further studies with prospective design and larger sample sizes are necessary to validate our results.

Direct Oral Anticoagulant Failures in Atrial Fibrillation With Stroke: Retrospective Admission Analysis and Novel Classification System

Introduction

Breakthrough acute ischemic stroke (AIS) in patients with known, nonvalvular Atrial Fibrillation (AF), on Direct Oral Anticoagulants (DOAC), is an ongoing clinical conundrum. Switching anticoagulants was shown to be ineffective in preventing recurrent AIS. Systematic, patient-level chart review of so-called "DOAC failures" may offer insight into this phenomenon.

Methods

We conducted an IRB-approved, 6-year, retrospective study of AIS admissions, already prescribed DOAC for known AF. We sought plausible, alternative reasons for the AIS using a novel classification schema, CLAMP: C for Compliance concerns, L for Lacunes (small-vessel disease), A for Arteriopathy (atherosclerosis, web, or vasculitis), M for Malignancy, and P for Patent Foramen Ovale (PFO). These categories were labeled as DOAC "Pseudo-failures." Conversely, absence of CLAMP variables were labeled as DOAC "Crypto-failures" conceivably from AF itself ("atriopathy") or pharmacokinetic/pharmacogenomic dysfunction (ie, altered DOAC absorption, clearance, metabolism, or genetic polymorphisms). Forward logistic regression analysis was performed on prespecified DOAC subgroups.

Results

Of 4890 AIS admissions, 606 had AF, and 87 were previously prescribed DOAC (14.4% overall DOAC failure rate, 2.4% annualized over 6 years). Pseudo-failures comprised 77%: Compliance concerns (48.9%), Lacunes (5.7%), Arteriopathy (17.0%), Malignancy (26.1%), and PFO (2.3%). Crypto-failures comprised 23%, had lower CHADSVASc scores (AOR = .65, P = .013), and occurred more with rivaroxaban (41%) than apixaban (16%) or dabigatran (5.6%).

Conclusion

In AIS patients with known AF, DOAC Pseudo-failures, with identified alternate etiologies, are 3 times more likely than DOAC Crypto-failures. The CLAMP schema represents a novel approach to diagnostic classification and therapeutic adjustments in patients already prescribed DOAC for AF.

Atrial Fibrillation Detected before or after Stroke: Role of Anticoagulation

BACKGROUND

Atrial fibrillation (AF) known before ischemic stroke (KAF) has been postulated to be an independent category with a recurrence risk higher than that of AF detected after stroke (AFDAS). However, it is unknown whether this risk difference is confounded by pre-existing anticoagulation, which is most common in KAF and also indicates a high ischemic stroke recurrence risk.

METHODS

Individual patient data analysis from 5 prospective cohorts of anticoagulated patients following AF-associated ischemic stroke. We compared the primary (ischemic stroke recurrence) and secondary outcome (all-cause death) among patients with AFDAS versus KAF and among anticoagulation-naïve versus previously anticoagulated patients using multivariable Cox, Fine-Gray models, and goodness-of-fit statistics to investigate the relative independent prognostic importance of AF-category and pre-existing anticoagulation.

RESULTS

Of 4,357 patients, 1,889 (43%) had AFDAS and 2,468 (57%) had KAF, while 3,105 (71%) were anticoagulation-naïve before stroke and 1,252 (29%) were previously anticoagulated. During 6,071 patient-years of follow-up, we observed 244 recurrent strokes and 661 deaths. Only pre-existing anticoagulation (but not KAF) was independently associated with a higher hazard for stroke recurrence in both Cox and Fine-Gray models. Models incorporating pre-existing anticoagulation showed better fit than those with AF category; adding AF-category did not result in better model fit. Neither pre-existing anticoagulation nor KAF were independently associated with death.

CONCLUSION

Our findings challenge the notion that KAF and AFDAS are clinically relevant and distinct prognostic entities. Instead of attributing an independently high stroke recurrence risk to KAF, future research should focus on the causes of stroke despite anticoagulation to develop improved preventive treatments. ANN NEUROL 2023;94:43-54.

The contribution of competing mechanisms in stroke despite anticoagulation in patients with atrial fibrillation

BACKGROUND

For reasons poorly understood, strokes frequently occur in patients with atrial fibrillation (AF) despite oral anticoagulation. Better data are needed to inform randomised trials (RCTs) of new strategies to prevent recurrence in these patients. We investigate the relative contribution of competing stroke mechanisms in patients with AF who have stroke despite anticoagulation (OAC+) compared with those who are anticoagulant naïve (OAC-) at the time of their event.

PATIENTS AND METHODS

We performed a cross-sectional study leveraging data from a prospective stroke registry (2015-2022). Eligible patients had ischemic stroke and AF. Stroke classification was performed by a single stroke-specialist blinded to OAC status using TOAST criteria. The presence of atherosclerotic plaque was determined using duplex ultrasonography, computerised tomography (CT) or magnetic resonance (MR) angiography. Imaging was reviewed by a single reader. Logistic regression was used to identify independent predictors of stroke despite anticoagulation.

RESULTS

Of 596 patients included, 198 (33.2%) were in the OAC+ group. A competing cause for stroke was more frequent in patients with OAC+ versus OAC- (69/198 (34.8%)) versus 77/398 (19.3%), p < 0.001). After adjustment, both small vessel occlusion (odds ratio (OR): 2.46, 95% CI: 1.20-5.06) and arterial atheroma (⩾50% stenosis) (OR: 1.78, 95% CI: 1.07-2.94) were independently associated with stroke despite anticoagulation.

DISCUSSION AND CONCLUSION

Patients with AF-associated stroke despite OAC are much more likely than patients who are OAC-naïve to have competing stroke mechanisms. Rigorous investigation for alternative stroke causes in stroke despite OAC has a high diagnostic yield. These data should be used to guide patient selection for future RCTs in this population.

Outcomes of patients with atrial fibrillation and ischemic stroke while on oral anticoagulation

AIMS

The prognosis of patients with atrial fibrillation (AF) and ischemic stroke while taking oral anticoagulation is poorly understood. This study aimed to characterize the outcomes of patients following a stroke event while on oral anticoagulation.

METHODS AND RESULTS

Individual participant data from five pivotal randomized trials of antithrombotic therapy in AF were used to assess the outcomes of patients with a post-randomization ischemic stroke while on study medication (warfarin, standard-, or lower-dose direct oral anticoagulant regimen) during trial follow-up. The primary outcome was recurrent ischemic stroke after the first post-randomization ischemic stroke. The primary analysis included 1163 patients with a first post-randomization ischemic stroke while on study medication (median age 73 years, 39.3% female, 35.4% history of stroke before trial enrollment). During a median continued follow-up of 337 days, 74 patients had a recurrent ischemic stroke [cumulative incidence at 1 year: 7.0%, 95% confidence interval (CI) 5.2%-8.7%]. The cumulative incidence of mortality at 3 months after stroke was 12.4% (95% CI 10.5%-14.4%). Consistent results for the incidence of recurrent ischemic stroke at 1 year were obtained in an analysis accounting for the competing risk of death (6.2%, 95% CI 4.8%-7.9%) and in a landmark analysis excluding the first 2 weeks after the index stroke and only including patients without permanent study drug discontinuation since then (6.8%, 95% CI 4.6%-8.9%).

CONCLUSION

Patients with AF and ischemic stroke while on oral anticoagulation are at increased risk of recurrent ischemic stroke and death. These patients currently have an unmet medical need.

Efficacy and Safety of Anticoagulant Therapy Versus Antiplatelet Therapy in Acute Ischemic Stroke Patients with Atrial Fibrillation

The efficacy and safety of anticoagulant therapy in patients with acute ischemic stroke (AIS) and atrial fibrillation (AF) remain uncertain. This study enrolled 431 AIS and AF patients from Nanjing Drum Tower Hospital between January 2019 and December 2021 and followed for 365 days to determine the associations between anticoagulants and clinical outcomes by assessing modified Rankin Scale (mRS) score, recurrent ischemic stroke/systemic embolism (IS/SE), all-cause mortality, intracranial hemorrhage (ICH) and major bleeding. Final analysis included 400 eligible patients and divided them into antiplatelet group (n  =  191) and anticoagulant group (n  =  209). Anticoagulant therapy was associated with excellent (mRS 0-1; adjusted odds ratio (aOR), 2.63; 95% confidence interval (CI), 1.61-4.30) and favorable functional outcomes (mRS 0-2; aOR, 2.82; 95% CI, 1.69-4.70) and lower risk of all-cause mortality (adjusted hazard ratio (aHR), 0.35; 95% CI, 0.21-0.57), ICH (aHR, 0.45; 95% CI, 0.23-0.87) and major bleeding (aHR, 0.51; 95% CI, 0.28-0.94), without increasing the risk of recurrent IS/SE (aHR, 0.75; 95% CI, 0.45-1.24). In conclusion, anticoagulant therapy may be a more effective and safer option than antiplatelet therapy for AIS patients with AF.

Some good reasons to proceed with the occlusion of the auricle

Atrial fibrillation (AF) is the most common arrhythmia. The most fearful complication of AF is represented by cardio-embolic stroke and 30% of ischaemic strokes are attributable to AF. The prevention of cardio-embolic risk is therefore based on oral anticoagulant therapy (OAT). Some categories of patients do not benefit from OAT. These are patients at increased bleeding risk and with varying degrees of contraindication to long-term anticoagulant therapy. On the opposite are those patients who develop an embolic event related to AF despite a well-conducted OAT. These types of patients benefit from an interventional approach, percutaneous closure of the left auricle (LAAO), aimed at eliminating what is the primary source of AF-related thrombo-embolism, precisely the left auricle. Percutaneous closure of the left auricle has proven to be an effective and safe procedure, significantly reducing the bleeding risks of patients who, after the procedure, will no longer have to take OAT. Furthermore, it has been shown to be effective in reducing cardio-embolic risk. Uncertainty still remains as to what is the optimal antithrombotic therapy after LAAO. In any case, LAAO represents a valid alternative to OAT for those patients in whom it is contraindicated or ineffective.