Should oral anticoagulants still be prescribed to patients with atrial fibrillation with a single stroke risk factor but at high bleeding risk? A nationwide cohort study

Association between antithrombotic drug regimen changes and clinical outcomes after stroke in atrial fibrillation

BACKGROUND

The impact of post-stroke antithrombotic regimen in atrial fibrillation is uncertain.

OBJECTIVE

This study aimed to describe antithrombotic therapy prescribing patterns after ischemic stroke and the impact on outcomes.

METHODS

A total of 23,165 patients with atrial fibrillation experiencing ischemic stroke were identified. Subsequent post-stroke events included recurrent ischemic stroke, intracranial hemorrhage, major bleeding, mortality, and composite outcomes.

RESULTS

Of those who were nonanticoagulated before a stroke, 33.5% remained nonanticoagulated and 39.2% were prescribed only antiplatelet agents (APs) after a stroke. Compared with non-vitamin K antagonist oral anticoagulants (NOACs) after stroke, there was a significant increase in ischemic stroke and mortality in nonanticoagulated patients (adjusted hazard ratio [aHR], 2.09 and 3.92) and AP users (aHR, 1.32 and 1.28). Post-stroke warfarin was associated with a significantly increased risk of major bleeding compared with NOACs (aHR, 1.23). Of 769 patients receiving NOACs before stroke and continuing NOACs after stroke, those switching to a different NOAC were associated with significantly higher risk of ischemic stroke (aHR, 2.07) and composite outcomes (aHR, 1.36-1.85) with no difference in intracranial hemorrhage, major bleeding, or mortality compared with those receiving the same NOAC after stroke. Of patients receiving NOACs before stroke, the risks of clinical events were similar between patients taking NOACs alone and those taking NOAC plus AP after stroke.

CONCLUSION

NOAC alone after stroke was associated with a better clinical outcome compared with nonanticoagulation, AP, or warfarin. Of patients already taking NOACs before stroke, the addition of AP did not confer additional benefits compared with NOACs alone. A change of NOAC types after stroke was associated with a 2-fold higher risk of ischemic stroke and composite outcomes.

Chinese guidelines for the diagnosis and management of atrial fibrillation

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, significantly impacting patients' quality of life and increasing the risk of death, stroke, heart failure, and dementia. Over the past two decades, there have been significant breakthroughs in AF risk prediction and screening, stroke prevention, rhythm control, catheter ablation, and integrated management. During this period, the scale, quality, and experience of AF management in China have greatly improved, providing a solid foundation for the development of the guidelines for the diagnosis and management of AF. To further promote standardized AF management, and apply new technologies and concepts to clinical practice timely and fully, the Chinese Society of Cardiology of Chinese Medical Association and the Heart Rhythm Committee of Chinese Society of Biomedical Engineering jointly developed the Chinese Guidelines for the Diagnosis and Management of Atrial Fibrillation. The guidelines comprehensively elaborated on various aspects of AF management and proposed the CHA2DS2‑VASc‑60 stroke risk score based on the characteristics of the Asian AF population. The guidelines also reevaluated the clinical application of AF screening, emphasized the significance of early rhythm control, and highlighted the central role of catheter ablation in rhythm control.

Chinese Guidelines for the Diagnosis and Management of Atrial Fibrillation

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, significantly impacting patients' quality of life and increasing the risk of death, stroke, heart failure, and dementia. Over the past two decades, there have been significant breakthroughs in AF risk prediction and screening, stroke prevention, rhythm control, catheter ablation, and integrated management. During this period, the scale, quality, and experience of AF management in China have greatly improved, providing a solid foundation for the development of guidelines for the diagnosis and management of AF. To further promote standardized AF management, and apply new technologies and concepts to clinical practice in a timely and comprehensive manner, the Chinese Society of Cardiology of the Chinese Medical Association and the Heart Rhythm Committee of the Chinese Society of Biomedical Engineering have jointly developed the Chinese Guidelines for the Diagnosis and Management of Atrial Fibrillation. The guidelines have comprehensively elaborated on various aspects of AF management and proposed the CHA2DS2-VASc-60 stroke risk score based on the characteristics of AF in the Asian population. The guidelines have also reevaluated the clinical application of AF screening, emphasized the significance of early rhythm control, and highlighted the central role of catheter ablation in rhythm control.

The optimal antithrombotic strategy for post-stroke patients with atrial fibrillation and extracranial artery stenosis-a nationwide cohort study

BACKGROUND

In post-stroke atrial fibrillation (AF) patients who have indications for both oral anticoagulant (OAC) and antiplatelet agent (AP), e.g., those with carotid artery stenosis, there is debate over the best antithrombotic strategy. We aimed to compare the risks of ischemic stroke, composite of ischemic stroke/major bleeding and composite of ischemic stroke/intracranial hemorrhage (ICH) between different antithrombotic strategies.

METHODS

This study included post-stroke AF patients with and without extracranial artery stenosis (ECAS) (n = 6390 and 28,093, respectively) identified from the Taiwan National Health Insurance Research Database. Risks of clinical outcomes and net clinical benefit (NCB) with different antithrombotic strategies were compared to AP alone.

RESULTS

The risk of recurrent ischemic stroke was higher for patients with ECAS than those without (12.72%/yr versus 10.60/yr; adjusted hazard ratio [aHR] 1.104, 95% confidence interval [CI] 1.052-1.158, p < 0.001). For patients with ECAS, when compared to AP only, non-vitamin K antagonist oral anticoagulant (NOAC) monotherapy was associated with lower risks for ischaemic stroke (aHR 0.551, 95% CI 0.454-0.669), the composite of ischaemic stroke/major bleeding (aHR 0.626, 95% CI 0.529-0.741) and the composite of ischaemic stroke/ICH (aHR 0.577, 95% CI 0.478-0.697), with non-significant difference for major bleeding and ICH. When compared to AP only, warfarin monotherapy was associated with higher risks of major bleeding (aHR 1.521, 95% CI 1.231-1.880), ICH (aHR 2.045, 95% CI 1.329-3.148), and the composite of ischaemic stroke and major bleeding. With combination of AP plus warfarin, there was an increase in ischaemic stroke, major bleeding, and the composite outcomes, when compared to AP only. NOAC monotherapy was the only approach associated with a positive NCB, while all other options (warfarin, combination of AP-OAC) were associated with negative NCB.

CONCLUSIONS

For post-stroke AF patients with ECAS, NOAC monotherapy was associated with lower risks of adverse outcomes and a positive NCB. Combination of AP with NOAC or warfarin did not offer any benefit, but more bleeding especially with AP-warfarin combination therapy.

Risk of Incident Atrial Fibrillation and Subsequent Use of Oral Anticoagulants in Patients with Dementia

BACKGROUND

 Dementia and atrial fibrillation (AF) have many shared risk factors. Besides, patients with dementia are under-represented in randomized trials, and even if AF is present, oral anticoagulants (OACs) are not prescribed frequently. This study aimed to report the incidence of newly diagnosed AF in dementia patients, and the impacts of use of vitamin K antagonist (VKA; e.g., warfarin) and non-VKA OAC (NOACs) on stroke and bleeding outcomes.

METHODS

 Our study utilized the Taiwan National Health Insurance Research Database. A total of 554,074 patients with dementia were compared with 554,074 age- and sex-matched patients without dementia regarding the risk of incident AF. Among patients with dementia who experienced incident AF, the risks of clinical events of patients treated with warfarin or NOACs were compared with those without OACs (reference group).

RESULTS

 The risk of incident AF was greater for patients with dementia compared with those without (adjusted hazard ratio [aHR]: 1.054; 95% confidence interval [CI]: 1.040-1.068 for all types of dementia, aHR: 1.035; 95% CI: 1.020-1.051 for presenile/senile dementia, and aHR: 1.125; 95% CI: 1.091-1.159 for vascular dementia). Among patients with dementia and experienced incident AF, warfarin use was associated with a higher risk of ischemic stroke (aHR: 1.290; 95% CI: 1.156-1.440), intracranial hemorrhage (ICH; aHR: 1.678; 95% CI: 1.346-2.090), and major bleeding (aHR: 1.192; 95% CI: 1.073-1.323) compared with non-OACs. NOAC use was associated with a lower risk of ischemic stroke (aHR: 0.421; 95% CI: 0.352-0.503) and composite risk of ischemic stroke or major bleeding (aHR: 0.544; 95% CI: 0.487-0.608) compared with non-OACs. These results were consistent among the patients after the propensity matching.

CONCLUSION

 In this large nationwide cohort, the risk of newly diagnosed AF was higher in patients with dementia (all dementia, presenile/senile dementia, and vascular dementia) compared with those without dementia. For patients with dementia who experienced incident AF, NOAC use was associated with a better clinical outcome compared with non-OAC. Patients with dementia require a holistic approach to their care and management, including the use of NOACs to reduce the risks of clinical events.

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.

Atrial fibrillation: mechanism and clinical management

ABSTRACT

Atrial fibrillation (AF), the most common sustained arrhythmia, is associated with a range of symptoms, including palpitations, cognitive impairment, systemic embolism, and increased mortality. It places a significant burden on healthcare systems worldwide. Despite decades of research, the precise mechanisms underlying AF remain elusive. Current understanding suggests that factors like stretch-induced fibrosis, epicardial adipose tissue (EAT), chronic inflammation, autonomic nervous system (ANS) imbalances, and genetic mutations all play significant roles in its development. In recent years, the advent of wearable devices has revolutionized AF diagnosis, enabling timely detection and monitoring. However, balancing early diagnosis with efficient resource utilization presents new challenges for healthcare providers. AF management primarily focuses on stroke prevention and symptom alleviation. Patients at high risk of thromboembolism require anticoagulation therapy, and emerging pipeline drugs, particularly factor XI inhibitors, hold promise for achieving effective anticoagulation with reduced bleeding risks. The scope of indications for catheter ablation in AF has expanded significantly. Pulsed field ablation, as a novel energy source, shows potential for improving success rates while ensuring safety. This review integrates existing knowledge and ongoing research on AF pathophysiology and clinical management, with emphasis on diagnostic devices, next-generation anticoagulants, drugs targeting underlying mechanisms, and interventional therapies. It offers a comprehensive mosaic of AF, providing insights into its complexities.

Non-vitamin K antagonist oral anticoagulants in atrial fibrillation patients without previous oral anticoagulants or stable under warfarin: a nationwide cohort study

AIMS

Investigations on non-VKA oral anticoagulants (NOACs) for atrial fibrillation (AF) patients without taking any oral anticoagulants (OACs) or staying well on warfarin were limited. We aimed to investigate the associations between stroke prevention strategies and clinical outcomes among AF patients who were previously well without taking any OACs or stayed well on warfarin for years.

METHODS AND RESULTS

The retrospective analysis included a total of 54 803 AF patients who did not experience an ischaemic stroke or intra-cranial haemorrhage (ICH) for years after AF was diagnosed. Among these patients, 32 917 patients who did not receive OACs were defined as the 'original non-OAC cohort' (group 1), and 8007 patients who continuously received warfarin were defined as the 'original warfarin cohort' (group 2). In group 1, compared to non-OAC, warfarin showed no significant difference in ischaemic stroke (aHR 0.979, 95%CI 0.863-1.110, P = 0.137) while those initiated NOACs were associated with lower risk (aHR 0.867, 95%CI 0.786-0.956, P = 0.043). When compared to warfarin, the composite of 'ischaemic stroke or ICH' and 'ischaemic stroke or major bleeding' was significantly lower in the NOAC initiator with an aHR of 0.927 (95%CI 0.865-0.994; P = 0.042) and 0.912 (95%CI 0.837-0.994; P < 0.001), respectively. In group 2, when compared to warfarin, those shifted to NOACs were associated with a lower risk of ischaemic stroke (aHR 0.886, 95%CI 0.790-0.993, P = 0.002) and major bleeding (aHR 0.849, 95%CI 0.756-0.953, P < 0.001).

CONCLUSIONS

The NOACs should be considered for AF patients who were previously well without taking OACs and those who were free of ischaemic stroke and ICH under warfarin for years.

Stroke Prevention in Atrial Fibrillation: A Scientific Statement of JACC: Asia (Part 1)

Atrial fibrillation is the most common sustained cardiac arrhythmia and is associated with substantial increases in the risk of stroke and systemic thromboembolism. With the successful introduction of the first non-vitamin K antagonist direct oral anticoagulant (NOAC) in 2009, the role of vitamin K antagonists has been replaced in most clinical settings except in a few conditions when NOACs are contraindicated. Data for the use of NOACs in different clinical scenarios have been accumulating in the recent decade, and a more sophisticated strategy for atrial fibrillation patients is now warranted. JACC: Asia recently appointed a working group to summarize the most updated information regarding stroke prevention in AF. This statement aimed to provide possible treatment option in daily practice. Local availability, cost, and patient comorbidities should also be considered. Final decisions may still need to be individualized and based on clinicians' discretion. This is the part 1 of the whole statement.

Risk of Ischemic Bowel Disease in Patients With Atrial Fibrillation Receiving Warfarin or Non-vitamin K Antagonist Oral Anticoagulants

Background

Although atrial fibrillation (AF) is a risk factor for ischemic bowel disease, data regarding the incidence of ischemic bowel disease in patients with anticoagulated AF were limited.

Methods

The present study used the Taiwan NHIRD and included newly diagnosed patients with AF aged ≥ 20 years without ischemic bowel disease from 2012 to 2018. A total of 69,549 patients taking warfarin or non-vitamin K antagonist oral anticoagulants (NOACs) constituted the final study group. We aimed to study the incidence of ischemic bowel disease in patients with AF receiving warfarin or NOACs. Secondary endpoints were also analyzed, including ischemic stroke, systemic embolism, myocardial infarction, mortality, intracranial hemorrhage (ICH), major bleeding, and composite adverse events (ischemic bowel disease or ICH or major bleeding).

Results

There were 43,787 patients taking NOACs and 25,762 patients taking warfarin. The overall incidence rate of ischemic bowel disease was 0.036% per year and increased with the CHA2DS2-VASc scores [0.013% for patients with a CHA2DS2-VASc score of 0 (men) or 1 (women), 0.022% for those with a CHA2DS2-VASc score of 1 (men) or 2 (women), and 0.039% for those with a CHA2DS2-VASc score ≥ 2 (men) or ≥ 3 (women)]. The risk of ischemic bowel disease was similar between NOAC and warfarin groups (0.036%/year vs. 0.037%/year; adjusted hazard ratio 0.802, p = 0.430), whereas the NOAC group had a significantly lower risk of secondary endpoints compared to the warfarin group.

Conclusion

We reported the incidence of ischemic bowel disease in patients with anticoagulated AF from a nationwide cohort database and observed a positive correlation between the increase of CHA2DS2-VASc scores and the incidence rate. Moreover, NOAC was as effective as warfarin for the risk of ischemic bowel disease.

Modified Taiwan Atrial Fibrillation Score for the Prediction of Incident Atrial Fibrillation

Background

We have proposed the Taiwan AF score consisting of age, male sex, hypertension, heart failure, coronary artery disease, end-stage renal disease, and alcoholism to predict incident atrial fibrillation (AF) in Asian population. We hypothesized that the modified Taiwan AF score (mTaiwan AF score) excluding alcoholism remained useful for predicting new onset AF.

Methods

A total of 7,220,654 subjects aged ≥ 40 years without a past history of cardiac arrhythmia were identified from a national cohort, and 438,930 incident AF occurred during a 16-year follow-up with an incidence of 0.42 per 100 person-years. The mTaiwan AF score ranging between −2 and 14 and its predictive accuracy of incident AF was analyzed.

Results

The areas under the receiver operating characteristic curve (AUCs) of the mTaiwan AF scores in predicting AF are 0.861 for 1-year follow-up, 0.829 for 5-year follow-up, 0.795 for 10-year follow-up, and 0.751 for 16-year follow-up. The risk of incident AF increased from 0.05%/year for patients with a score of −2 to 6.98%/year for those having a score of 14. Patients were classified into three groups based on the tertile values of the mTaiwan AF scores—group 1 (score −2-3), group 2 (score 4-9) and group 3 (score 10-14). The annual risks of incident AF were 0.20, 1.33, and 3.36% for group 1, 2, and 3, respectively. Compared to patients in group 1, the hazard ratios of incident AF were 5.79 [95% confidence interval (CI) 3.75-7.75] for group 2 and 8.93 (95% CI 6.47-10.80) for group 3.

Conclusions

We demonstrated that the mTaiwan AF score based on age and clinical comorbidities could be used to predict incident AF in Asian population.

2021 Focused Update Consensus Guidelines of the Asia Pacific Heart Rhythm Society on Stroke Prevention in Atrial Fibrillation: Executive Summary

The consensus of the Asia Pacific Heart Rhythm Society (APHRS) on stroke prevention in atrial fibrillation (AF) has been published in 2017 which provided useful clinical guidance for cardiologists, neurologists, geriatricians, and general practitioners in the Asia-Pacific region. In these years, many important new data regarding stroke prevention in AF were reported. The practice guidelines subcommittee members comprehensively reviewed updated information on stroke prevention in AF, and summarized them in this 2021 focused update of the 2017 consensus guidelines of the APHRS on stroke prevention in AF. We highlighted and focused on several issues, including the importance of the AF Better Care pathway, the advantages of non-vitamin K antagonist oral anticoagulants (NOACs) for Asians, the considerations of use of NOACs for Asian AF patients with single one stroke risk factor beyond gender, the role of lifestyle factors on stroke risk, the use of oral anticoagulants during the "coronavirus disease 2019" pandemic, etc. We fully realize that there are gaps, unaddressed questions, and many areas of uncertainty and debate in the current knowledge of AF, and the physician's decision remains the most important factor in the management of AF.

2021 Focused update of the 2017 consensus guidelines of the Asia Pacific Heart Rhythm Society (APHRS) on stroke prevention in atrial fibrillation

The consensus of the Asia Pacific Heart Rhythm Society (APHRS) on stroke prevention in atrial fibrillation (AF) has been published in 2017 which provided useful clinical guidance for cardiologists, neurologists, geriatricians, and general practitioners in Asia-Pacific region. In these years, many important new data regarding stroke prevention in AF were reported. The Practice Guidelines subcommittee members comprehensively reviewed updated information on stroke prevention in AF, and summarized them in this 2021 focused update of the 2017 consensus guidelines of the APHRS on stroke prevention in AF. We highlighted and focused on several issues, including the importance of AF Better Care (ABC) pathway, the advantages of non-vitamin K antagonist oral anticoagulants (NOACs) for Asians, the considerations of use of NOACs for Asian patients with AF with single 1 stroke risk factor beyond gender, the role of lifestyle factors on stroke risk, the use of oral anticoagulants during the "coronavirus disease 2019" (COVID-19) pandemic, etc. We fully realize that there are gaps, unaddressed questions, and many areas of uncertainty and debate in the current knowledge of AF, and the physician's decision remains the most important factor in the management of AF.