Risk of stroke and intracranial hemorrhage in 9727 Chinese with atrial fibrillation in Hong Kong

Selection of Non-vitamin K Antagonist Oral Anticoagulant for Stroke Prevention in Atrial Fibrillation Based on Patient Profile: Perspectives from Vietnamese Experts. Part 1

In Asia, especially Vietnam, AF is a common arrhythmia and is linked to a higher risk of stroke and systemic embolism. Anticoagulation therapy for stroke prevention in AF patients can result in bleeding complications. To effectively manage AF, adopting appropriate anticoagulation and addressing modifiable risk factors are crucial. Vietnamese clinicians are particularly interested in non-vitamin K antagonist oral anticoagulants (NOACs), a recent development in AF treatment. However, the lack of head-to-head trials comparing NOACs makes selecting a specific NOAC challenging. This review aims to provide a comprehensive overview of the available clinical evidence on NOACs for stroke prevention in AF to assist clinicians in making informed decisions and improving treatment outcomes in patients with AF. The first part of this review will present the current landscape of AF in Vietnam, focusing on AF prevalence and highlighting gaps in clinical practice. Furthermore, this part extensively discusses the anticoagulation strategy for both primary and secondary stroke prevention in AF.

Global and regional burden of ischemic stroke associated with atrial fibrillation, 2009-2019

The extent of the preventable burden of ischaemic stroke associated with atrial fibrillation (AF) remains uncertain to date. To address this knowledge gap, we utilised the comparative risk assessment methodology to estimate the burden of ischaemic stroke associated with AF at both global and regional levels. The population attributable fraction for ischaemic stroke and AF was obtained from published literature, while data on the prevalence, incidence, deaths, and disability-adjusted life years (DALY) associated with ischaemic stroke were sourced from the Global Burden of Disease study database. Our analysis revealed that in 2019, globally, there were an estimated 0.7 (95% uncertainty interval [UI] of 0.55 to 0.83) million incident cases, 6.9 (5.81 to 8.12) million prevalence cases, 0.3 0.25 to 0.34) million deaths and 5.7 (4.91 to 6.57) million DALY resulting from ischaemic stroke associated with AF. The age-standardised death and DALY rates declined between 2009 and 2019 in all regions to varying degrees. Conversely, the age-standardised incidence and prevalence rates reduced only in high-income countries, Central Europe, Eastern Europe and Central Asia and Latin America and Caribbean regions. It is likely that our findings under-estimated the true burden of ischaemic stroke associated with AF due to limitations such as the use of a fixed population attributable fraction and poor quality of data. Nevertheless, we believe that our estimates provide valuable insights and highlight the urgent need for optimised management of AF through the implementation of efficacious interventions. Such efforts can help reduce the occurrence of preventable ischaemic strokes.

Female "Paradox" in Atrial Fibrillation-Role of Left Truncation Due to Competing Risks

Female sex in patients with atrial fibrillation (AF) is a controversial and paradoxical risk factor for stroke-controversial because it increases the risk of stroke only among older women of some ethnicities and paradoxical because it appears to contradict male predominance in cardiovascular diseases. However, the underlying mechanism remains unclear. We conducted simulations to examine the hypothesis that this sex difference is generated non-causally through left truncation due to competing risks (CR) such as coronary artery diseases, which occur more frequently among men than among women and share common unobserved causes with stroke. We modeled the hazards of stroke and CR with correlated heterogeneous risk. We assumed that some people died of CR before AF diagnosis and calculated the hazard ratio of female sex in the left-truncated AF population. In this situation, female sex became a risk factor for stroke in the absence of causal roles. The hazard ratio was attenuated in young populations without left truncation and in populations with low CR and high stroke incidence, which is consistent with real-world observations. This study demonstrated that spurious risk factors can be identified through left truncation due to correlated CR. Female sex in patients with AF may be a paradoxical risk factor for stroke.

Oral Anticoagulation in Patients With Advanced Chronic Kidney Disease and Atrial Fibrillation: Beyond Anticoagulation

The optimal approach to prevent stroke and systemic embolism in patients with advanced chronic kidney disease (CKD) and atrial fibrillation remains unresolved. We conducted a narrative review to explore areas of uncertainty and opportunities for future research. First, the relationship between atrial fibrillation and stroke is more complex in patients with advanced CKD than in the general population. The currently employed risk stratification tools do not adequately discriminate between patients deriving a net benefit and those suffering a net harm from oral anticoagulation. Anticoagulation initiation should probably be more restrictive than is currently advocated by official guidelines. Recent evidence reveals that the superior benefit-risk profile of non-vitamin K antagonist oral anticoagulants (NOACs) vs vitamin K antagonists (VKAs) observed in the general population and in moderate CKD can be extended to advanced CKD. The NOACs yield better protection against stroke, cause less major bleeding, are associated with less acute kidney injury and a slower decline of CKD, and are associated with a lower incidence of cardiovascular events than VKAs. The VKAs may be harmful in CKD patients, in particular in patients with a high bleeding risk and labile international normalized ratio. The better safety and efficacy of NOACs as opposed to VKAs may be particularly evident in advanced CKD as a result of better on-target anticoagulation with NOACs, harmful off-target vascular effects of VKAs, and beneficial off-target vascular effects of NOACs. The intrinsic vasculoprotective effects of NOACs are supported by animal experimental evidence as well as by findings of large clinical trials and may result in use of NOACs beyond their anticoagulant properties.

Racial and Ethnic Disparities in Stroke Prevention for Atrial Fibrillation

Racial and ethnic disparities in health care are well documented, although often underappreciated. In the setting of atrial fibrillation, stroke risk and severity may be higher in underrepresented ethnic populations. Additionally, the risk of bleeding is not uniform, and pharmacogenetics play an important role in anticoagulant therapy. In this narrative review, we discuss the complex issues surrounding stroke prevention in underrepresented ethnic groups with atrial fibrillation.

Gender Differences in Atrial Fibrillation: From the Thromboembolic Risk to the Anticoagulant Treatment Response

Atrial fibrillation (AF) is the most common cardiac arrhythmia associated with an increased thromboembolic risk. The impact of the female sex as an independent risk factor for thromboembolic events in AF is still debated. Background and Objectives: The aim of this review is to evaluate the gender-related differences in cardioembolic risk and response to anticoagulants among AF patients. Materials and Methods: The PubMed database is used to review the reports about gender differences and thromboembolic risk in atrial fibrillation. Results: Non-vitamin K oral anticoagulants (NOACs) represent the gold standard for thromboembolic risk prevention in patients with non-valvular atrial fibrillation (NVAF). Despite a similar rate of stroke and systemic embolism (SE) among men and women in NOACs or vitamin K antagonists (VKAs) treatment, the use of NOACs in AF women is associated with a lower risk of intracranial bleeding, major bleeding, and all-cause mortality than in men. Conclusions: The female sex can be defined as a stroke risk modifier rather than a stroke risk factor since it mainly increases the thromboembolic risk in the presence of other risk factors. Further studies about the efficacy and safety profile of NOACs according to sex are needed to support clinicians in performing the most appropriate and tailored anticoagulant therapy, either in male or female AF patients.

Safety and Tolerability of Tecarfarin (ATI-5923) in Healthy Chinese Volunteers: Multiple Oral Dose-Escalation Phase I Trial

BACKGROUND

Tecarfarin (ATI-5923), a structural analog of warfarin, was designed to provide more uniform and stable anticoagulation.

OBJECTIVE

We aimed to evaluate the safety, tolerability, pharmacokinetic and pharmacodynamic profile of tecarfarin when administered in multiple ascending doses (MADs) to healthy Chinese volunteers.

METHODS

Forty healthy Chinese volunteers were enrolled into four sequential cohorts (10, 20, 30, and 40 mg), with 10 subjects in each cohort. Participants in the MAD study for each sequential cohort were dose-titrated to achieve the target international normalized ratio (INR 1.7-2.0) for 14 days. Safety and tolerability were assessed throughout the study.

RESULTS

The pharmacokinetic and pharmacodynamic profile of tecarfarin was investigated in a healthy Chinese population. Dose titration of tecarfarin was necessary to keep the INR in the target range in all subjects in the 20, 30 and 40 mg cohorts and a few subjects (n = 3) in the 10 mg cohort. Tecarfarin was well tolerated without serious adverse events. Only one treatment-related adverse event (hematochezia) resulted in early withdrawal from the MAD 40 mg cohort.

CONCLUSION

Tecarfarin was well-tolerated by Chinese volunteers. Dose titration was needed for tecarfarin doses larger than 20 mg to keep the INR in the target range.

REGISTRATION

ClinicalTrials.gov identifier: NCT04627116.

Psychometric Validation of the Chinese Version of the Atrial Fibrillation Knowledge Scale in Chinese Patients With Atrial Fibrillation

BACKGROUND

Assessment of patients' knowledge on atrial fibrillation (AF) and its management is important for evaluating their learning needs. However, a validated and comprehensive instrument to be used among Chinese patients is yet to be developed.

OBJECTIVES

The aim of this study was to develop and validate the Chinese version of the Atrial Fibrillation Knowledge Scale (AFKS-C) in Chinese patients.

METHODS

The 11-item AFKS was translated, and then content and face validations were conducted by an expert panel and patients with AF. A sample of 255 patients with AF was recruited from a university-affiliated hospital to evaluate its psychometric properties. The internal consistency and test-retest reliability were evaluated using the Kuder-Richardson formula 20 and κ statistics. Item analysis determined the item difficulty index and item discrimination coefficients. Factorial and discriminant validity were evaluated using exploratory factor analysis and the known-groups method.

RESULTS

The content validity index of the AFKS-C was 0.94, and the Kuder-Richardson formula 20 value was 0.60. The difficulty indices of the items ranged from 0.36 to 0.89, and the point-biserial coefficients of the items ranged from 0.122 to 0.255, indicating sufficient discriminatory ability. The test-retest reliability was acceptable, because the κ values ranged from 0.234 to 0.710. The principal axis factoring analysis indicated a 3-factor structure that explained 50.4% of the total variance. The AFKS-C also demonstrated satisfactory discriminant validity, having yielded significantly different scores between patients with newly diagnosed and established AF.

CONCLUSION

The AFKS-C has acceptable psychometric properties and can be used to measure the knowledge of patients and evaluate the effects of patient education programs.

Stroke Prevention in Atrial Fibrillation

PURPOSE OF REVIEW

Atrial fibrillation is associated with a significant increase in stroke and systemic embolism. This review explores the areas of stroke prevention.

RECENT FINDINGS

In the last decade, NOAC has overtaken warfarin as the anticoagulant of choice for stroke prevention in AF. For patients unable to take anticoagulation, LAA closure has proven to be a valid option. The use of digital devices has led to widespread consumer-directed AF screening. It remains to be determined if all device detect AF pose the same amount of risk as recent studies have shown that short and infrequent episodes of AF may not benefit from anticoagulation. Stroke prevention is paramount in the management of AF. In this review we describe the risk factors contributing to stroke, recent advances in antithrombotic therapies, and the increasing role of digital health in guiding AF detection and stroke prevention.

Protocol for Home-Based Solution for Remote Atrial Fibrillation Screening to Prevent Recurrence Stroke (HUA-TUO AF Trial): a randomised controlled trial

INTRODUCTION

Current international guidelines recommend ECG monitoring after an ischaemic stroke to detect atrial fibrillation (AF) in order to prevent stroke recurrence. However, optimal strategies to detect AF and the downstream management to prevent stroke recurrence remain to be established. The objective of the study was to explore the use of long-term home-based ECG monitoring for AF detection and stroke prevention in patients with a history of stroke.

METHODS AND ANALYSIS

This prospective, randomised, open-label trial with blinded endpoint adjudication aimed to evaluate the efficacy of long-term home-based ECG monitoring for AF detection and stroke prevention in a 24-month period. Patients aged >18 years with a history of ischaemic stroke will be stratified according to the time from the index ischaemic stroke: <1, 1-3 and >3 years and then randomised in 1:1 to (1) home-based AF screening and (2) control. The home-based AF screening system comprises (1) a handheld single-lead ECG recorder (Comfit Healthcare Devices, Hong Kong SAR, China) and (2) a patient-facing smartphone application specially designed for the study. Patients randomised to the home-based AF group will record a 30 s single-lead ECG using a specially designed handheld ECG device every morning or when symptomatic. All remotely obtained data will be automatically transmitted in real-time through the study smartphone application to a secured cloud hosting and analysed using an artificial intelligence-based diagnostic system. When a diagnosis of AF is made with the system, the patients will be called back for a formal cardiology consultation within 1 week. The primary endpoint is the time to first detection of AF at 24 months of follow-up. Secondary endpoints include recurrent stroke or transient ischaemic attack, initiation of long-term anticoagulation therapy, hospitalisation for heart failure, cardiovascular death and all-cause death.

ETHICS AND DISSEMINATION

The study protocol has been approved by the institutional review board of The University of Hong Kong, and Hong Kong West Cluster, Hospital Authority, Hong Kong SAR, China. Results will be published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT04523649.

Long-Term Cost-Effectiveness Comparison of Catheter Ablation and Antiarrhythmic Drugs in Atrial Fibrillation Treatment Using Discrete Event Simulation

OBJECTIVES

To evaluate the lifetime cost-effectiveness of 3 widely used atrial fibrillation (AF) treatments from the perspectives of Chinese healthcare system: antiarrhythmic drugs (AADs), ThermoCool SmartTouch guided by ablation index (STAI), and second-generation cryoballoon (CB2).

METHODS

A discrete event simulation (DES) model was implemented to compare the lifetime cost-effectiveness of AADs, STAI, and CB2. AF disease progression was explicitly modeled based on the Atrial Fibrillation Progression Trial clinical study results. The base-case analysis assumed that patients with paroxysmal AF (PAF) entered the model at the age of 55 years and had a CHA2DS2-VASc (Congestive heart failure, Hypertension, Age ( > 65 = 1 point, > 75 = 2 points), Diabetes, previous Stroke/transient ischemic attack (2 points)-Vascular disease (peripheral arterial disease, previous myocardial infarction, aortic atheroma), Age 65 to 74 years, and Sex category) score of 2 for males and 3 for females. Model parameter uncertainties were incorporated throughout the DES simulation with full probabilistic model parameterization.

RESULTS

The lifetime cost-effectiveness evaluations showed that patients treated with AADs gained an average of 4.98 quality-adjusted life-years (QALYs) and 9.63 life-years (LYs) at an average cost of US dollar (USD) 15 374. Patients treated with CB2 gained 5.92 QALYs and 10.74 LYs at an average cost of USD 26 811. The STAI group gained an average of 6.55 QALYs and 11.57 LYs at an average cost of USD 24 722. The incremental cost-effectiveness ratios was USD 5927 and USD 12 167 per QALY for STAI versus AADs and CB2 versus AADs, respectively. Assuming the willingness-to-pay threshold for China is USD 30 390 per QALY, both ablation treatments will be cost-effective compared with AADs for patients with PAF.

CONCLUSIONS

The DES model demonstrated that catheter ablations are more cost-effective than AADs for patients with PAF under the healthcare system in China. Among catheter ablation technologies, STAI provides better outcomes at lower costs.

Validation of the CHA2DS2-VA Score (Excluding Female Sex) in Nonvalvular Atrial Fibrillation Patients: A Nationwide Population-Based Study

Sex (i.e., female sex) confers one point for the CHA2DS2-VASc score. For this reason, females with atrial fibrillation (AF) always have a CHA2DS2-VASc score of at least 1. To compare the CHA2DS2-VA (excluding female sex) and CHA2DS2-VASc scores in Korean AF patients using the Korean National Health Insurance Service database, we analyzed the risk of ischemic stroke in nonvalvular AF patients between 2013 and 2017. The predictive values of the CHA2DS2-VA and CHA2DS2-VASc scores for ischemic stroke were evaluated using the C-statistic and net reclassification improvement (NRI). The primary outcome was the occurrence of ischemic stroke. A total of 185,637 patients with AF (49.7% women) were included in this study. The mean ages were 66.5 years for females and 64.9 years for males. The incidence of ischemic stroke in male patients was similar to females (3.63%/year vs. 3.72%/year, p = 0.273, respectively). In addition, no sex difference was apparent for stroke risk in AF patients stratified by risk factor component and age group. In the C-statistic analysis, the predictive ability of the CHA2DS2-VA score for ischemic stroke was similar to the CHA2DS2-VASc score. Additionally, CHA2DS2-VA performed better for predicting ischemic stroke in AF patients with risk scores of ≥2 (AUC 0.701 vs. 0.689, z = 4.596, p < 0.001) or those aged ≥75 years (AUC 0.715 vs. 0.701, z = 4.957, p < 0.001). In Korean AF patients, female sex is not a specific risk factor that contributes to the development of ischemic stroke. The CHA2DS2-VA score, which excludes female sex, may be a more suitable risk score for guiding anticoagulation decisions in Korean AF patients.

Novel model-based point scoring system for predicting stroke risk in atrial fibrillation patients: Results from a nationwide cohort study with validation

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This study used rigorous statistical method to construct the novel AF-CA-Stroke score and demonstrated that the novel stroke risk stratification tool had significantly higher discrimination abilities than conventional scores.

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This study exhibited that the status of various age stratifications and receiving AF ablation shall be considered in managing AF treatment.

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Based on the AF-CA-Stroke score, around 80–85% patients may take benefits form AF ablation procedures with lower stroke risks, and they may not be necessary to receive oral anticoagulants after receiving successful AF ablations.

Background

The stroke risk scoring system for atrial fibrillation (AF) patients can vary considerably based on patients’ status while receiving ablation. This study aimed to demonstrate a novel scoring system for stroke risk stratification based on the status of catheter ablation.

Methods

First, 787 patients with AF undergoing ablation were matched according to age, sex, and underlying diseases with the same number of patients not undergoing ablation using the propensity-score (PS)-matched cohort. Multivariate Cox model-derived coefficients were used to construct a simple point-based clinical model using the PS-matched cohort. Thereafter, the novel model (AF-CA-Stroke score) was validated in a nationwide AF cohort.

Results

The AF-CA-Stroke score was calculated based on age (point = 5), ablation status (point = 4), prior history of stroke (point = 4), chronic kidney disease (point = 2), diabetes mellitus (point = 1), and congestive heart failure (point = 1). Risk function to predict the 1-, 5-, 10-year absolute stroke risks was reported. The estimated area under the receive operating characteristic curve of the AF-CA-Stroke score in the PS-matched cohort was 0.845 (95% confidence interval: 0.824–0.865) to predict long-term stroke. A validation study showed that discrimination abilities in the AF-CA-Stroke scores were significantly higher than those in the CHADS₂/CHA₂DS_2-VASc scores. The best cut-off value of the AF-CA-Stroke score to predict future strokes was ≥ 5.

Conclusions

This novel model-based point scoring system effectively identifies stroke risk using clinical factors and AF ablation status of patients with AF. Various age stratifications and AF ablation should be considered in AF management.

Utility of the CHA2DS2-VASc score for predicting ischaemic stroke in patients with or without atrial fibrillation: a systematic review and meta-analysis

AIMS

Anticoagulants are the mainstay treatment for stroke prevention in patients with non-valvular atrial fibrillation (NVAF), and the CHA2DS2-VASc score is widely used to guide anticoagulation therapy in this cohort. However, utility of CHA2DS2-VASc in NVAF patients is debated, primarily because it is a vascular scoring system, which does not incorporate atrial fibrillation related parameters. Therefore, we conducted a meta-analysis to estimate the discrimination ability of CHA2DS2-VASc in predicting ischaemic stroke overall, and in subgroups of patients with or without NVAF.

METHODS AND RESULTS

PubMed and Embase databases were searched till June 2020 for published articles that assessed the discrimination ability of CHA2DS2-VASc, as measured by C-statistics, during mid-term (2-5 years) and long-term (>5 years) follow-up. Summary estimates were reported as random effects C-statistics with 95% confidence intervals (CIs). Seventeen articles were included in the analysis. Nine studies (n = 453 747 patients) reported the discrimination ability of CHA2DS2-VASc in NVAF patients, and 10 studies (n = 138 262 patients) in patients without NVAF. During mid-term follow-up, CHA2DS2-VASc predicted stroke with modest discrimination in the overall cohort [0.67 (0.65-0.69)], with similar discrimination ability in patients with NVAF [0.65 (0.63-0.68)] and in those without NVAF [0.69 (0.68-0.71)] (P-interaction = 0.08). Similarly, at long-term follow-up, CHA2DS2-VASc had modest discrimination [0.66 (0.63-0.69)], which was consistent among patients with NVAF [0.63 (0.54-0.71)] and those without NVAF [0.67 (0.64-0.70)] (P-interaction = 0.39).

CONCLUSION

This meta-analysis suggests that the discrimination power of the CHA2DS2-VASc score in predicting ischaemic stroke is modest, and is similar in the presence or absence of NVAF. More accurate stroke prediction models are thus needed for the NVAF population.

Type of atrial fibrillation and outcomes in patients without oral anticoagulants

BACKGROUND

The effect of type of atrial fibrillation (AF) on adverse outcomes in Chinese patients without oral anticoagulants (OAC) was controversial.

HYPOTHESIS

The type of AF associated with adverse outcomes in Chinese patients without OAC.

METHODS

A total of 1358 AF patients without OAC from a multicenter, prospective, observational study was included for analysis. Univariable and multivariable Cox regression models were utilized. Net reclassification improvement analysis was performed for the assessment of risk prediction models.

RESULTS

There were 896(66%) patients enrolled with non-paroxysmal AF (NPAF) and 462(34%) with paroxysmal AF (PAF). The median age was 70.9 ± 12.6 years, and 682 patients (50.2%) were female. During 1 year of follow-up, 215(16.4%) patients died, and 107 (8.1%) patients experienced thromboembolic events. Compared with the PAF group, NPAF group had a notably higher incidence of all-cause mortality (20.2% vs. 9.4%, p < .001), thromboembolism (10.5% vs. 3.8%, p < .001). After multivariable adjustment, NPAF was a strong predictor of thromboembolism (HR 2.594, 95%CI 1.534-4.386; p < .001), all-cause death (HR 1.648, 95%CI 1.153-2.355; p = .006). Net reclassification improvement analysis indicated that the addition of NPAF to the CHA₂ DS₂ -VASc score allowed an improvement of 0.37 in risk prediction for thromboembolic events (95% CI 0.21-0.53; p < .001).

CONCLUSIONS

In Chinese AF patients who were not on OAC, NPAF was an independent predictor of thromboembolism and mortality. The addition of NPAF to the CHA₂ DS₂ -VASc score allowed an improvement in the accuracy of the prediction of thromboembolic events.

Atrial fibrillation in low- and middle-income countries: a narrative review

Preventing premature non-communicable disease mortality necessitates a thorough review of one of the most important risk factors for stroke, which is atrial fibrillation (AF). The latter and AF-related stroke are still considered to be problems of high-income countries and are frequently overlooked in low- and middle-income countries (LMICs). In this narrative review, we provide an overview of studies that evaluated at least one of the following determinants of AF burden in LMICs: current epidemiology and trends, stroke prevention, health outcomes, and economic burden. Studies focusing on samples close to the general population (including community- and primary care-based samples) indicate sex-specific prevalence rates up to 7.4% in LMICs. Although AF prevalence is still higher in high-income countries than LMICs, the gap in AF burden between these two groups has been reducing in the past three decades. Oral anticoagulant (OAC) therapy for stroke prevention is underused in LMICs, and there are little data on OAC therapy in relation to stroke risk scores, such as CHA2DS2-VASc. Available data also points to higher morbidity and mortality for patient with AF in LMICs than their counterparts in high-income countries. Data on the consequent economic burden in LMICs is scarce, but it is reasonable to consider it will follow the same trend as that observed for health outcomes. Raising the visibility of AF as a public health problem in LMICs is necessary as a first step to providing adequate care for patients with this condition.

Antithrombotic therapy and the risk of new-onset dementia in elderly patients with atrial fibrillation

BACKGROUND

Atrial fibrillation (AF) is associated with an increased risk of dementia. Little is known about the relationship of antithrombotic therapy and the risk of dementia in patients with AF without clinical stroke.

METHOD

This was an observational study based on a hospital AF registry. Patients aged 65-85 years at the time of AF diagnosis were identified via the computerised database of the clinical management system. Patients with prior stroke or known cognitive dysfunction were excluded. The primary outcome was newly diagnosed dementia during the follow-up period.

RESULTS

3284 patients (mean age 76.4±5.3 years, 51.6% male) were included for analysis. The mean CHA₂DS₂-VASc score was 3.94±1.44. 18.5% patients were prescribed warfarin, 39.8% were prescribed aspirin and 41.7% were prescribed no antithrombotic therapy. After a mean follow-up of 3.6 years, 71 patients (2.2%) developed dementia, giving rise to an incidence of 0.61%/year. The incidence of dementia were 1.04%/year, 0.69%/year and 0.14%/year for patients on no therapy, aspirin and warfarin, respectively. Both univariate and multivariate analyses showed that age ≥75 years, female gender and high CHA₂DS₂-VASc score were associated with significantly higher risk of dementia; warfarin use was associated with significantly lower risk of dementia (HR: 0.14%, 95% CI 0.05 to 0.36, p<0.001). Patients on warfarin with time in therapeutic range (TTR) ≥65% had a non-significant trend towards a lower risk of dementia compared with those with TTR <65%.

CONCLUSION

In elderly AF patients, warfarin therapy was associated with a significantly lower risk of new-onset dementia compared those with no therapy or aspirin.

Detection rate and treatment gap for atrial fibrillation identified through screening in community health centers in China (AF-CATCH): A prospective multicenter study

BACKGROUND

Atrial fibrillation (AF) is underdiagnosed and especially undertreated in China. We aimed to investigate the prevalence of unknown and untreated AF in community residents (≥65 years old) and to determine whether an education intervention could improve oral anticoagulant (OAC) prescription.

METHODS AND FINDINGS

We performed a single-time point screening for AF with a handheld single-lead electrocardiography (ECG) in Chinese residents (≥65 years old) in 5 community health centers in Shanghai from April to September 2017. Disease education and advice on referral to specialist clinics for OAC treatment were provided to all patients with actionable AF (newly detected or undertreated known AF) at the time of screening, and education was reinforced at 1 month. Follow-up occurred at 12 months. In total, 4,531 participants were screened (response rate 94.7%, mean age 71.6 ± 6.3 years, 44% male). Overall AF prevalence was 4.0% (known AF 3.5% [n = 161], new AF 0.5% [n = 22]). The 183 patients with AF were older (p < 0.001), taller (p = 0.02), and more likely to be male (p = 0.01), and they had a higher prevalence of cardiovascular disease than those without AF (p < 0.001). In total, 85% (155/183) of patients were recommended for OAC treatment by the established guidelines (CHA2DS2-VASc ≥ 2 for men; ≥ 3 for women). OAC prescription rate for known AF was 20% (28/138), and actionable AF constituted 2.8% of all those screened. At the 12-month follow-up in 103 patients (81% complete), despite disease education and advice on specialist referral, only 17 attended specialist clinics, and 4 were prescribed OAC. Of those not attending specialist clinics, 71 chose instead to attend community health centers or secondary hospital clinics, with none prescribed OAC, and 15 had no review. Of the 17 patients with new AF and a class 1 recommendation for OAC, only 3 attended a specialist clinic, and none were prescribed OAC. Of the 28 AF patients taking OAC at baseline, OAC was no longer taken in 4. Ischemic stroke (n = 2) or death (n = 3) occurred in 5/126 (4%), with none receiving OAC. As screening was performed at a single time point, some paroxysmal AF cases may have been missed; thus, the rate of new AF may be underestimated.

CONCLUSIONS

We demonstrated a noticeable gap in AF detection and treatment in community-based elderly Chinese: actionable AF constituted a high proportion of those screened. Disease education and advice on specialist referral are insufficient to close the gap. Before more frequent or intensive screening for unknown AF could be recommended in China, greater efforts must be made to increase appropriate OAC therapy in known AF to prevent AF-related stroke.

A Long-Term Cost-Effectiveness Analysis Comparing Radiofrequency Catheter Ablation with Antiarrhythmic Drugs in Treatment of Chinese Patients with Atrial Fibrillation

INTRODUCTION

Radiofrequency catheter ablation (RFCA) is widely used to treat atrial fibrillation (AF) in China.

OBJECTIVE

We aimed to determine the long-term cost effectiveness of RFCA versus antiarrhythmic drugs (AADs) in treating AF from the perspective of third-party payers.

METHODS

The model was structured as a 12-month decision tree leading to a Markov model that simulated the follow-up treatment outcomes and costs with time horizons of 8, 15, and 20 years. Comparators were standard-of-care AADs. Clinical parameters captured normal sinus rhythm, AF, stroke, post-stroke, intracranial hemorrhage (ICH), gastrointestinal bleeding, post-ICH, and death. The risk of operative death, procedural complications, and adverse drug toxicity were also considered. The model output was quality-adjusted life-years (QALYs) and incremental cost per QALY gained.

RESULTS

RFCA incurred more costs than the AADs but resulted in more QALYs gained than did AADs. The incremental cost per QALY gained with RFCA versus AADs was ¥66,764, ¥36,280, and ¥29,359 at 8, 15, and 20 years, respectively. The sensitivity analyses showed that the results were most sensitive to the changes in RFCA cost and CHADS₂ score (clinical prediction rule for assessing the risk of stroke in patients with non-rheumatic AF).

CONCLUSION

Compared with AADs, RFCA significantly improves clinical outcomes and QALYs among patients with paroxysmal or persistent AF. From the Chinese payer's perspective, RFCA is a cost-effective therapy over long-term horizons.

Age Threshold for Ischemic Stroke Risk in Atrial Fibrillation

Background and Purpose- Although older age is one of the most important risk factor for stroke in atrial fibrillation (AF), the appropriate age threshold (eg, CHA₂DS₂-VASc score [congestive heart failure, hypertension, age ≥75 years (doubled), diabetes mellitus, prior stroke or transient ischemic attack (doubled), vascular disease, age 65-74 years, female], 1 point for age 65-74 years, 2 points for age ≥75 years) for increased risk is controversial because actual age thresholds may differ between countries and ethnic groups. We investigated the age threshold for ischemic stroke risk among Asian AF patients. Methods- Using National Health Insurance Service database, including 426 650 oral anticoagulant-naive nonvalvular AF patients from 2005 to 2015, with ≤2 nongender-related CHA₂DS₂-VASc risk scores (CHA₂DS₂-VASc score 0-2 in males, 1-3 in females), we assessed the risk of ischemic stroke in AF patients according to the age. Results- Patients who fulfill the age risk criterion (age, 65-74 years) without other risk factors showed a significantly higher risk of stroke (4.76 per 100 person-years [100PY]; adjusted hazard ratio, 2.25; 95% confidence interval [CI], 2.17-2.36) compared with patients with 1 risk score other than age (1.87/100PY). Patients aged 55 to 59 years with no risk factors showed similar risk of stroke (1.94/100PY; adjusted hazard ratio, 0.95; 95% confidence interval, 0.90-1.00) than patients with 1 risk score (2.06/100PY). Patients aged 65 to 69 years and no other risk factors had similar stroke risk (4.08/100PY; adjusted hazard ratio, 0.93; 95% confidence interval, 0.90-0.97) than patients with 2 nongender-related risk scores (4.42/100PY). Conclusions- Older age is the most important predictor of ischemic stroke in AF, particularly for patients with low to intermediate risk of stroke. These nationwide data suggest lowering the current age threshold (age, ≥65 years) in the CHA₂DS₂-VASc score to age ≥55 years might be appropriate among Asian patients with AF.

A nurse-coordinated integrated care model to support decision-making and self-care in patients with atrial fibrillation: A study protocol

AIM

This study aims to evaluate the effects of a nurse-coordinated, empowerment-based integrated care model on self-care behaviours and psychosocial outcomes in patients with atrial fibrillation and to explore how this intervention affects patients' self-care behaviours and quality of life.

DESIGN

This mixed-methods study comprises a randomized controlled trial and an exploratory qualitative study.

METHODS

A total of 392 community-dwelling patients aged ≥65 years with a confirmed diagnosis of atrial fibrillation, a high stroke risk and no oral anticoagulants treatment will be recruited from the medical outpatient clinics of a university-affiliated hospital. The patients will be randomly allocated to intervention or control groups, which will receive treatment via the nurse-coordinated integrated care model or standard care, respectively. We hypothesize that compared with patients receiving standard care, atrial fibrillation patients exposed to the nurse-coordinated care model will be more likely to achieve compatible patient and physician decisions regarding the use of oral anticoagulants, better changes in medication adherence, anxiety, depression and health-related quality of life after the intervention. A subsample of 30 participants in the intervention group will also participate in a qualitative interview to provide their views and perceptions about the intervention. The ethical approval has obtained on 5 July 2018. This study is supported by a grant from the Research Grants Council of the Hong Kong Special Administrative Region on 29 June 2018.

DISCUSSION

This study will uniquely adopt an empowerment-based approach to equip patients as active agents in atrial fibrillation management through a nurse-coordinated integrated care model that comprehensively addresses their needs.

IMPACT

Patients with atrial fibrillation are currently receiving inadequate guideline-recommended care. This study will address this important evidence-practice gap by optimizing oral anticoagulant prescription and therapeutic effects and promotes effective patient self-care, so as to achieve worldwide reductions in atrial fibrillation-related morbidity, mortality, and healthcare burdens.

CLINICAL TRIAL REGISTRATION

This study has been registered at ClinicalTrials.gov (NCT03924739).

TIMI risk score for secondary prevention of recurrent cardiovascular events in a real-world cohort of post-non-ST-elevation myocardial infarction patients

Background

Patients who survive non-ST-elevation myocardial infarction (NSTEMI) are at heightened risk of recurrent cardiovascular events. Data on long-term secondary atherothrombotic risk stratification are limited.

Objectives

To stratify post-NSTEMI patients for risk of recurrent cardiovascular events to maximise benefit from aggressive secondary prevention strategies using the TIMI Risk Score for Secondary Prevention (TRS 2°P) score in a real-world cohort of NSTEMI patients.

Methods and results

This was a single-centre observational study of 891 post-NSTEMI patients (73.7 ± 12.7 years; male: 54.2%). The TRS 2°P is a nine-point risk stratification tool to predict cardiovascular events in patients with established cardiovascular disease. The primary outcome was a composite endpoint of cardiovascular death, non-fatal MI and non-fatal ischaemic stroke. After a median follow-up of 31 months (IQR: 11.4 – 60.2), 281 patients (31.5%) had developed a primary outcome (13.3%/year) including 196 cardiovascular deaths, 94 non-fatal MIs and 22 non-fatal strokes. The TRS 2°P score was strongly associated with the primary outcome. The annual incidence of primary composite endpoint for patients with TRS 2°P score =0 was 1.6%, and increased progressively to 47.4% for those with a TRS 2°P score ≥6 (HR: 20.18, 95% CI: 4.85 to 84.05, p<0.001). Similar associations were also observed between the TRS 2°P score and cardiovascular death and MI (fatal and non-fatal), but not non-fatal ischaemic stroke.

Conclusion

The TRS 2°P score stratified post-NSTEMI patients for risk of future cardiovascular events and potentially help guide the selection of more aggressive secondary prevention therapy.

Modelling projections for the risks related with atrial fibrillation in East Asia: a focus on ischaemic stroke and death

Aims

In the Far East, there has generally been low uptake of oral anticoagulants (OACs) using vitamin K antagonists (VKA, e.g. warfarin) for stroke prevention in atrial fibrillation (AF), but OAC use has been increasing more recently, with the introduction of the non-vitamin K antagonist oral anticoagulants (NOACs). To explore the risks of ischaemic stroke (IS) and death related to AF in East Asia using modelling projections.

Methods and results

We performed a modelling analysis of possible trends of IS and death rates in AF patients from the time period of only VKA use to current increasing trends of NOAC use projecting until 2050 in East Asia. Data from published articles on the prevalence of AF, IS, and death were used to model estimated event rates. In 2030, the estimated AF population in East Asia will be 608 100, with the use of NOACs leading to a reduction of 82 259 ISs and 16 917 deaths. There was an estimated annual risk reduction of 5484 ISs and 1128 deaths from 2016 to 2030, respectively. The AF population is estimated to reach 861 900 in 2050, with a reduction of 206 315 ISs and 139 353 deaths.

Conclusion

This modelling analysis suggests that the transition from VKA to NOACs may greatly help in reducing the burden of IS and death caused by AF in the East Asian region.

Discover high-risk factor combinations using Bayesian network from cohort data of National Stoke Screening in China

BACKGROUND

In recent years, the increasing incidence and prevalence of stroke has brought a heavy economic burden on families and society in China. The Ministry of Health of the Peoples' Republic of China initiated the national stroke screening and intervention program in 2011 for stroke prevention and control. In the screening, only those who have been classified to "potential high-risk" group in preliminary screening need further examination and physician confirmation to determine the risk level of stroke in rescreening. However, at the beginning of the program, the "potential high-risk" classification method in the preliminary screening are determined by experts based on their experience. The primary aim of this study is to study the causality of stroke and risk factors in middle-aged population using the cohort data, and to explore whether the stroke screening and intervention program should include more precise "potential high-risk" evaluation criteria for this age group in preliminary screening.

METHOD

We use the cohort data of screening between 2013 and 2017 in this study. After data cleaning, the cohort consists of 48,007 people aged from 40 to 59 who are free of stroke at baseline. We use Bayesian networks to develop models.

RESULT

The results show that the stroke incidence in middle-aged population with certain two risk factors is higher than some of that with three factors, which is in keeping with our previous study results. We can take the ratio of the stroke incidence with combinations of risk factors and incidence without any of the risk factors as a variable threshold. By adjusting the threshold, we can get precise stroke preliminary screening criteria to achieve a balance between economy and efficiency.

CONCLUSION

We find that the criteria used in preliminary screening are not reasonable enough. There is a need for national stroke screening and intervention program to further include some more important risk factors or combinations of two risk factors as classification criteria in the preliminary screening. The results of the study can directly guide stroke screening program in China to make the screening more accurate and efficient.

Risk factors of thromboembolism in nonvalvular atrial fibrillation patients with low CHA2DS2-VASc score

The risk of thromboembolism in patients with CHA2DS2-VASc score of 0 to 1 was low, and the anticoagulant therapy was not recommended. Although the CHA2DS2-VASc score was low, there were still many patients suffered from thrombotic events and stroke. We aim to investigate the risk factors of thrombotic events in nonvalvular atrial fibrillation (NVAF) patients with low CHA2DS2-VASc score.We retrospectively enrolled 595 consecutive NVAF patients with low CHA2DS2-VASc score (male: CHA2DS2-VASc = 0, female: CHA2DS2-VASc = 1). The general clinical data, blood biochemical data, and echocardiography results of the 595 patients were collected. Multivariate logistic regression models were used to evaluate risk factors of thrombosis. Receiver operating characteristic curve was used to identify the optimal cut-off value of the independent risk factors. A P value of <.05 (2-sided) was considered to be statistically significant.In multivariate analysis, lipoprotein (a) (Lp(a)) plasma level and left atrium diameter (LAD) were positively related to thromboembolism in NVAF patients with CHA2DS2-VASc score of 0 to 1 after adjustment for age, gender, and other variables (odds ratio [OR] = 1.02, 95% confidence interval [CI]: 1.01-1.03; OR = 1.13, 95% CI: 1.06-1.18). Lp(a) exerted a significant predictive value with area under the curve (AUC) of 0.62 (95% CI: 0.55-0.68, P < .01). The optimal cut-off value for Lp(a) predicting thrombotic events was 27.2 mg/dL (sensitivity 45.7%, specificity 73.4%). LAD showed a significant predictive value with AUC of 0.71 (95% CI: 0.64-0.78, P < .01). The optimal cut-off point for LAD predicting thrombotic events was 43.5 mm (sensitivity 47.1%, specificity 85.8%).High Lp(a) plasma level and left atrial dilatation might be independent risk factors of thrombotic events for NVAF patients with low CHA2DS2-VASc score.

Risk Factor Management for Atrial Fibrillation

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia in the general population. Many cardiovascular diseases and concomitant conditions increase the risk of the development of AF, recurrent AF, and AF-associated complications. Knowledge of these factors and their management is hence important for the optimal management of patients with AF. Recent studies have suggested that lowering the blood pressure threshold can improve the patients' outcome. Moreover, adverse events associated with a longer duration of hypertension can be prevented through strict blood pressure control. Pre-hypertension, impaired fasting glucose, abdominal obesity, weight fluctuation, and exposure to air pollution are related to the development of AF. Finally, female sex is not a risk factor of stroke, and the age threshold for stroke prevention should be lowered in Asian populations. The management of diseases related to AF should be provided continuously, whereas lifestyle factors should be monitored in an integrated manner.

2018 Korean Guideline of Atrial Fibrillation Management

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia in the general population. The Korean Heart Rhythm Society organized a Korean AF Management Guideline Committee and analyzed all available studies regarding the management of AF, including studies on Korean patients. This guideline is based on recent data of the Korean population and the recent guidelines of the European Society of Cardiology, European Association for Cardio-Thoracic Surgery, American Heart Association, and Asia Pacific Heart Rhythm Society. Expert consensus or guidelines for the optimal management of Korean patients with AF were achieved after a systematic review with intensive discussion. This article provides general principles for appropriate risk stratification and selection of anticoagulation therapy in Korean patients with AF. This guideline deals with optimal stroke prevention, screening, rate and rhythm control, risk factor management, and integrated management of AF.

Female Sex as a Risk Factor for Ischemic Stroke and Systemic Embolism in Chinese Patients With Atrial Fibrillation: A Report From the China-AF Study

Background Previous studies have provided conflicting results as to whether women are at higher risk than men for thromboembolism in the setting of atrial fibrillation ( AF ). We investigated whether women with AF were at higher risk of ischemic stroke in the China-AF (China Atrial Fibrillation Registry) Study. Methods and Results A total of 19 515 patients were prospectively enrolled between August 2011 and December 2016 in the China- AF Study. After exclusion of patients receiving anticoagulation or ablation therapy, 6239 patients (2574 women) with results from at least 6 months of follow-up were used for the analysis. Cox proportional hazards models were performed to evaluate whether female sex was an independent risk factor for thromboembolism after multivariate adjustment. The primary outcome was the time to the first occurrence of ischemic stroke or systemic embolism. After a mean follow-up of 2.81±1.46 years, 152 female patients reached the primary outcome, as compared with 172 male patients. Crude incidence rates of thromboembolism between women and men were of borderline statistical significance (2.08 versus 1.68 per 100 patient-years, P=0.058). After multivariable analysis, female sex was not independently associated with an increased thromboembolism risk (hazard ratio 1.09, 95% confidence interval 0.86-1.39). There was no significant difference in thromboembolism risk by sex stratified by age and presence or absence of risk factors ( P for interaction all >0.1). Conclusions Although crude incidence rates of thromboembolism were higher in Chinese female patients with AF compared with male patients, female sex did not emerge as an independent risk factor for thromboembolism on multivariate analysis. Clinical Trial Registration URL : http://www.chictr.org.cn/ . Unique identifier: Chi CTR - OCH -13003729.

Stroke Risk and Treatment in Patients with Atrial Fibrillation and Low CHA2DS2-VASc Scores: Findings From the ORBIT-AF I and II Registries

Background Current American College of Cardiology/American Heart Association guidelines suggest that for patients with atrial fibrillation who are at low risk for stroke (CHA2DS2VASc=1) (or women with CHA2DS2VASc=2) a variety of treatment strategies may be considered. However, in clinical practice, patterns of treatment in these "low-risk" patients are not well described. The objective of this analysis is to define thromboembolic event rates and to describe treatment patterns in patients with low-risk CHA2DS2VASc scores. Methods and Results We compared characteristics, treatment strategies, and outcomes among patients with a CHA2DS2VASc=0, CHA2DS2VASc=1, females with a CHA2DS2VASc=2, and CHA2DS2VASc ≥2 in ORBIT-AF (Outcomes Registry for Better Informed Treatment of Atrial Fibrillation) I & II. Compared with CHA2DS2VASc ≥2 patients (84.2%), those with a CHA2DS2VASc=0 (60.3%), 1 (69.9%), and females with a CHA2DS2VASc score=2 (72.4%) were significantly less often treated with oral anticoagulation ( P<0.0001). Stroke rates were low overall and ranged from 0 per 100 patient-years in those with CHA2DS2VASc=0, 0.8 (95% confidence interval [CI] [0.5-1.2]) in those with CHA2DS2VASc=1, 0.8 (95% CI [0.4-1.6]) in females with a CHA2DS2VASc score=2, and 1.7 (95% CI [1.6-1.9]) in CHA2DS2VASc ≥2. All-cause mortality (per 100 patient-years) was highest in females with a CHA2DS2VASc score=2 (1.4) (95% CI [0.8-2.3]), compared with patients with a CHA2DS2VASc=0 (0.2) (95% CI [0.1-1.0]), and CHA2DS2VASc=1 (1.0) (95% CI [0.7-1.4]), but lower than patients with a CHA2DS2VASc ≥2 (5.7) (95% CI [5.4-6.0]). Conclusion The majority of CHA2DS2VASc=0-1 patients are treated with oral anticoagulation. In addition, the absolute risks of death and stroke/transient ischemic attack were low among both male and females CHA2DS2VASc=0-1 as well as among females with a CHA2DS2VASc score=2. Clinical Trial Registration URL: http://www.clinicaltrials.gov . Unique identifier: NCT01701817.

Sex differences in stroke and major adverse clinical events in patients with atrial fibrillation: A systematic review and meta-analysis of 993,600 patients

BACKGROUND

Atrial fibrillation (AF) is the most commonly diagnosed arrhythmia, which is associated with an increased risk of stroke. Several studies have suggested that female AF patients could have a greater risk for stroke and thromboembolic events (TE).

METHODS

A systematic literature review update and meta-analysis was conducted using Pubmed. The search used the terms "atrial fibrillation", "gender", "sex", "female", "women", "stroke", "thromboembolism". Main aim of the study was to compare and male AF patients for occurrence of stroke and TE. Secondary outcomes were: major bleeding, cardiovascular (CV) death and all-cause death.

RESULTS

Forty-four studies were included in the analysis including 993,603 patients (48.9% women). After pooling the data, there was a higher risk of stroke for women vs. male AF patients (hazard ratio [HR]: 1.24; 95% confidence intervals [CIs]: 1.14-1.36). Overall, TE risk was not different between female and male patients, despite sensitivity analysis left some uncertainties. No sex differences were found for major bleeding, CV death and all-cause death. A significant relationship between increasing age and the difference in stroke risk between female and male AF patients was found (Delta HR: 1.01; 95% CI: 1.00-1.03 for each year of age increase).

CONCLUSIONS

Female patients with AF are at increased risk of stroke compared to men. A significant relationship between increasing age and stroke risk in women compared to men was found, most evident at age > 65 years. Female sex may act as a stroke risk modifier, particularly in elderly and very elderly AF subjects, conferring a significant increase in stroke risk.

Effectiveness of a nongovernmental organization-led large-scale community atrial fibrillation screening program using the smartphone electrocardiogram: An observational cohort study

BACKGROUND

Opportunistic screening for atrial fibrillation (AF) in patients older than 65 years is currently recommended.

OBJECTIVE

We aim to examine the effectiveness of a nongovernmental organization-led community-based AF screening program carried out by trained layperson volunteers.

METHODS

AF screening was performed using a smartphone electrocardiogram in 11,574 participants.

RESULTS

Among all participants, smartphone electrocardiograms were interpretable in 10,735 citizens (92.8%; 8564 female citizens [79.8%]; mean age 78.6 ± 8.1 years). Two hundred forty-four participants (2.3%; 95% confidence interval [CI] 2-2.6%; 172 female participants [70.5%]; mean age 79.5 ± 7.9 years) had AF and were advised over phone by a nurse to seek medical attention. Newly diagnosed AF was found in 74 participants (0.69%; 95% CI 0.54-0.84%) with a mean CHA₂DS₂-VASc score of 3.9 ± 1.5. Thirty-six of them (48%; 95% CI 36.6-59.4%) were asymptomatic. The number needed to screen for 1 newly diagnosed AF was 145. Telephone follow-up of participants with AF was conducted 9 months after screening. Of 72 participants with newly diagnosed AF and indicated for oral anticoagulation, 47 (65.3%; 95% CI 54.3-76.3%) sought medical attention, 17 (23.6%; 95% CI 13.8-33.4%) received oral anticoagulants, and 16 (22.2%; 95% CI 12.6-31.8%) had 100% compliance. The number needed to screen for 1 appropriately treated newly diagnosed AF was 671.

CONCLUSION

This nongovernmental organization-led community-based AF screening program is effective in identifying citizens with newly diagnosed AF. However, the effectiveness of the program in subsequently leading them to receive appropriate oral anticoagulation therapy is weakened by the lack of a more structured downstream management pathway.

Systematic Screening for Atrial Fibrillation in the Community: Evidence and Obstacles

With an ageing population globally, the burden of atrial fibrillation (AF) and its consequent complication of stroke and risk of mortality will continue to increase. Although opportunistic screening for AF by pulse check or ECG rhythm strip for people >65 years of age is currently recommended, data are now emerging that demonstrate the possible benefits of systematic community screening. Such screening is capable of identifying previously undiagnosed AF in 0.5-3.0 % of all those screened. The effectiveness of screening programmes will be markedly weakened by the lack of a structured downstream management pathway, making it a mandatory component in any AF screening programme for the general population. Different tools, especially smartphone-based devices, have made AF screening in the community more feasible. However, the sensitivities and positive predictive values of the current versions of automated diagnostic algorithms for AF have to be improved further to increase the cost-efficiency of screening programmes.

Impact of provision of time in therapeutic range value on anticoagulation management in atrial fibrillation patients on warfarin

INTRODUCTION

The importance of time in therapeutic range (TTR) in patients prescribed warfarin therapy for stroke prevention in atrial fibrillation (AF) cannot be overemphasised.

AIM

To evaluate the impact of provision of TTR results during clinic visits on anticoagulation management.

DESIGN

Single-centred, randomised controlled study.

SETTING

Fifteen arrhythmia clinics in Hong Kong.

PATIENTS

AF patients prescribed warfarin.

INTERVENTIONS

Provision of TTR or no provision of TTR.

MAIN OUTCOME MEASURES

A documented discussion between doctors and patients about switching warfarin to a non-vitamin K oral anticoagulant (NOAC).

RESULTS

Four hundred and eighty one patients with AF prescribed warfarin were randomly assigned to (1) a TTR provision group or (2) control. Their mean age was 73.6±12.0 years and 60.7% were men. The mean CHA₂DS₂-VASc score was 3.2±1.6 and the mean HASBLED score was 1.7±1.2. The mean TTR was 63.9%±29.9%. At the index clinic visit, 71 of 481 patients (14.8%) had a documented discussion about switching warfarin to a NOAC. Patients with provision of TTR results were more likely to discuss switching warfarin to a NOAC than controls (19.1% vs 10.6%, P=0.03), especially those with a TTR <65% (35.2% vs 10.6%, P<0.001). A higher proportion of patients with provision of TTR results switched to a NOAC (5.9% vs 4.1%, P=0.49).

CONCLUSIONS

The provision of TTR among patients on warfarin was associated with a discussion about switching from warfarin to a NOAC in those with TTR <65%, but did not result in actual switching to a NOAC, suggesting additional barriers.

Association between modified CHA2DS2-VASc Score with Ankle-Brachial index < 0.9

The ankle-brachial index (ABI) is a reliable diagnostic examination for peripheral arterial occlusive disease (PAOD). We previously reported CHADS₂ score was significantly correlated with PAOD. However, the association between CHA₂DS₂-VASc score and ABI < 0.9 is not evaluated in the literature. The aim of the present study was to investigate whether CHA₂DS₂-VASc score has a strong association with PAOD. We enrolled 1482 patients in this study. PAOD was defined as ABI < 0.9 in either leg. Vascular disease in CHA₂DS₂-VASc score was modified as vascular disease except PAOD. Of the 1482 subjects, the prevalence of ABI < 0.9 was 5.6%. Multivariate analysis showed that the increased age, decreased estimated glomerular filtration rate and increased modified CHA₂DS₂-VASc score (OR, 1.764; p < 0.001) were independent associated with ABI < 0.9. In addition, the percentage of ABI < 0.9 in patients with modified CHA₂DS₂-VASc score of 0, 1, and <2 were 0%, 0.9%, and 0.7%, respectively (All < 1%). Our study demonstrated modified CHA₂DS₂-VASc score was significantly associated with ABI < 0.9. Calculation of modified CHA₂DS₂-VASc score might be useful in identifying patients with PAOD and in stratifying the risk of PAOD in non-AF patients.

Implications of CHA2DS2-VASc Score in Stroke Patients with Atrial Fibrillation: An Analysis of 938 Korean Patients

BACKGROUND AND AIMS

The aim of this study was to investigate the stroke mechanisms and associated conditions influencing the decision regarding stroke thromboprophylaxis in patients with atrial fibrillation (AF) plus ischemic stroke, according to the CHA2DS2-VASc score.

METHODS

We evaluated 938 consecutive patients with a diagnosis of AF plus transient ischemic attack/ischemic stroke. Based on the CHA2DS2-VASc scores, patients were stratified as score 0 or 1 (n = 151), score 2 (n = 146), score 3 (n = 213), score 4 (n = 185), or score ≥5 (n = 243).

RESULTS

Patients with a higher CHA2DS2-VASc score were more likely to have noncardioembolic stroke mechanism (p = 0.001). Large-artery atherosclerosis causing stenosis >50% was more frequently observed in the high CHA2DS2-VASc group (p < 0.001). Coronary artery disease and the use of antiplatelet agents were more prevalent in the higher group (p < 0.001). A high CHA2DS2-VASc score was associated with a higher frequency of cerebral microbleeds and a higher Fazekas grade for leukoaraiosis (p < 0.001). The HAS-BLED score was correlated with the CHA2DS2-VASc score (γ = 0.650; p < 0.001).

CONCLUSIONS

A higher CHA2DS2-VASc score is associated with noncardioembolic mechanisms of stroke and with a higher risk of bleeding. Strategies to treat macro/microangiopathy such as use of statin for plaque stabilization, as well as oral anticoagulants with a lower bleeding risk, are needed in these patients.

Stroke Prevention in Atrial Fibrillation: Focus on Asian Patients

Atrial fibrillation (AF) is the most common arrhythmia conferring a fivefold increased risk of stroke. Stroke prevention is the cornerstone of management of patients with AF. Asians have a generally higher incidence of AF-related risks of stroke and bleeding (particularly intracranial bleeding), compared with non-Asians. Despite the well-documented efficacy and relative safety of oral anticoagulation for stroke prevention among Asians, the suboptimal use of oral anticoagulation remains common. The current narrative review aims to provide a summary of the available evidence on stroke prevention among patients with AF focused on the Asia region, regarding stroke and bleeding risk evaluation, the performance of oral anticoagulation, and current use of thromboprophylaxis.

Regional Differences in Antithrombotic Treatment for Atrial Fibrillation: Insights from the GLORIA-AF Phase II Registry

Introduction  Although guideline-adherent antithrombotic therapy (ATT) for stroke prevention in atrial fibrillation (AF) is associated with lower mortality and thromboembolism, ATT uptake shows geographic variation worldwide. We aimed to assess thromboembolic risk and baseline ATT by geographic region and identify factors associated with prescription of ATT in a large, truly global registry of patients with recently diagnosed AF.

Methods and Results  Our analysis comprises 15,092 patients newly diagnosed with non-valvular AF at risk for stroke, enrolled in Phase II of Global Registry on Long-Term Oral Antithrombotic Treatment in Patients with Atrial Fibrillation (GLORIA-AF). Global oral anticoagulation (OAC) use was 79.9%, being highest in Europe (90.1%), followed by Africa/Middle East (87.4%) and Latin America (85.3%), North America (78.3%) and Asia (55.2%). Among OAC users, vitamin K antagonists (VKAs) have been replaced by non-VKA OACs (NOACs) as the more prevalent OAC option in all regions, with highest use in North America (66.5%) and lowest in Asia (50.2%). In Asia, OAC was 80.4% in community hospitals but only 49.8% in university hospitals and 42.6% in specialist offices, and varied from 21.0% in China to 89.7% in Japan (NOACs at 5.8% in China and 83.3% in Japan). Globally, 76.5% of low-risk patients were prescribed ATT (46.1% OAC), whereas 17.7% high-risk patients were not anticoagulated (Europe 8.8%; North America 18.9%; Asia 42.4%).

Conclusion  Substantial inter- and intra-regional differences in ATT for stroke prevention in AF are evident in this global registry. While guideline-adherent ATT can be further improved, NOACs are the main contributor to high OAC use worldwide.

Bleeding risk with dabigatran, rivaroxaban, warfarin, and antiplatelet agent in Asians with non-valvular atrial fibrillation

It is not understood if dabigatran or rivaroxaban are superior to antiplatelet agents (AA) for safety outcomes in Asians with non-valvular atrial fibrillation (NVAF). In this study we evaluated the bleeding risk of dabigatran, rivaroxaban, warfarin and AA in Asians with NVAF. This national retrospective cohort study analyzed 6,600, 3,167, 5,338 and 8,238 consecutive NVAF patients taking dabigatran, rivaroxaban, warfarin or AAs (including aspirin, clopidogrel or ticlopidine), respectively, from June 1, 2012 to December 31, 2013. Propensity-score weighting was used to balance covariates across study groups. Patients were followed until the first occurrence of any bleeding outcome or the end of the study. The CHA₂DS₂-VASc scores were 4.1±1.6, 4.1±1.6, 3.3±1.8 and 2.4±1.6 for the dabigatran, rivaroxaban, warfarin, and AA groups, respectively. There were 5,822 (88.2%) and 164 (5.2%) patients taking low dose dabigatran and rivaroxaban, respectively. Hazard ratios (95% confidence intervals) for dabigatran, rivaroxaban, or warfarin versus AA were: intracranial hemorrhage, 0.36 (0.23-0.57;PP=0.0037) and 1.34 (0.89-2.02;P=0.1664); gastrointestinal bleeding, 0.44 (0.32-0.59;PP=0.0189); and all hospitalized major bleeding, 0.41 (0.32-0.53;PP=0.0644) and 0.90 (0.70-1.16;P=0.4130) after adjustment. The risk reduction of all major bleeding for dabigatran versus AA persisted on subgroup analysis. In conclusion, we observed that dabiagtran was associated with a lower risk of all major bleeding in Asians with NVAF, whereas rivaroxaban had a similar risk of all major bleeding compared with antiplatelet agents after adjustment of comorbidities.

2017 consensus of the Asia Pacific Heart Rhythm Society on stroke prevention in atrial fibrillation

Atrial fibrillation (AF) is the most common sustained arrhythmia, causing a 2-fold increase in mortality and a 5-fold increase in stroke. The Asian population is rapidly aging, and in 2050, the estimated population with AF will reach 72 million, of whom 2.9 million may suffer from AF-associated stroke. Therefore, stroke prevention in AF is an urgent issue in Asia. Many innovative advances in the management of AF-associated stroke have emerged recently, including new scoring systems for predicting stroke and bleeding risks, the development of non-vitamin K antagonist oral anticoagulants (NOACs), knowledge of their special benefits in Asians, and new techniques. The Asia Pacific Heart Rhythm Society (APHRS) aimed to update the available information, and appointed the Practice Guideline sub-committee to write a consensus statement regarding stroke prevention in AF. The Practice Guidelines sub-committee members comprehensively reviewed updated information on stroke prevention in AF, emphasizing data on NOACs from the Asia Pacific region, and summarized them in this 2017 Consensus of the Asia Pacific Heart Rhythm Society on Stroke Prevention in AF. This consensus includes details of the updated recommendations, along with their background and rationale, focusing on data from the Asia Pacific region. We hope this consensus can be a practical tool for cardiologists, neurologists, geriatricians, and general practitioners in this region. 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.

Diagnostic performance of an automatic blood pressure measurement device, Microlife WatchBP Home A, for atrial fibrillation screening in a real-world primary care setting

OBJECTIVE

To evaluate the diagnostic performance of a UK National Institute for Health and Care Excellence-recommended automatic oscillometric blood pressure (BP) measurement device incorporated with an atrial fibrillation (AF) detection algorithm (Microlife WatchBP Home A) for real-world AF screening in a primary healthcare setting.

SETTING

Primary healthcare setting in Hong Kong.

INTERVENTIONS

This was a prospective AF screening study carried out between 1 September 2014 and 14 January 2015. The Microlife device was evaluated for AF detection and compared with a reference standard of lead-I ECG.

PRIMARY OUTCOME MEASURES

Diagnostic performance of Microlife for AF detection.

RESULTS

5969 patients (mean age: 67.2±11.0 years; 53.9% female) were recruited. The mean CHA₂DS₂-VASc ( C : congestive heart failure [1 point]; H : hypertension [1 point]; A₂ : age 65-74 years [1 point] and age ≥75 years [2 points]; D : diabetes mellitus [1 point]; S : prior stroke or transient ischemic attack [2 points]; VA : vascular disease [1 point]; and Sc : sex category [female] [1 point])score was 2.8±1.3. AF was diagnosed in 72 patients (1.21%) and confirmed by a 12-lead ECG. The Microlife device correctly identified AF in 58 patients and produced 79 false-positives. The corresponding sensitivity and specificity for AF detection were 80.6% (95% CI 69.5 to 88.9) and 98.7% (95% CI 98.3 to 98.9), respectively. Among patients with a false-positive by the Microlife device, 30.4% had sinus rhythm, 35.4% had sinus arrhythmia and 29.1% exhibited premature atrial complexes. With the low prevalence of AF in this population, the positive and negative predictive values of Microlife device for AF detection were 42.4% (95% CI 34.0 to 51.2) and 99.8% (95% CI 99.6 to 99.9), respectively. The overall diagnostic performance of Microlife device to detect AF as determined by area under the curves was 0.90 (95% CI 0.89 to 0.90).

CONCLUSIONS

In the primary care setting, Microlife WatchBP Home was an effective means to screen for AF, with a reasonable sensitivity of 80.6% and a high negative predictive value of 99.8%, in addition to its routine function of BP measurement. In a younger patient population aged <65 years with a lower prevalence of AF, Microlife WatchBP Home A demonstrated a similar diagnostic accuracy.