Epidemiology of Atrial Fibrillation: The Australian and Asia-Pacific Perspective

Effects of Longitudinal Changes in Anemia Status on Clinical Outcomes in Patients With Non-Valvular Atrial Fibrillation - Analysis From the Hokuriku-Plus AF Registry

BACKGROUND

Anemia, a common comorbidity in older patients with heart failure (HF) and atrial fibrillation (AF), is associated with an increased risk of adverse events. This study evaluated the prognostic effects of longitudinal changes in anemia status on clinical outcomes in patients with AF.

METHODS AND RESULTS

We prospectively evaluated data of 1,388 patients with AF from the Hokuriku-Plus AF Registry (1,010 men; mean [±SD] age 72.3±9.7 years) and recorded the incidence of death, HF, thromboembolism, and major bleeding. Of these patients, the 1,233 for whom hemoglobin levels were available at baseline and at the 1-year follow-up were further evaluated. Patients were categorized into 3 groups based on longitudinal changes in 1-year anemia status: Group 1, AF without anemia; Group 2, AF with improved anemia; and Group 3, AF with sustained or new-onset anemia. Over the 1-5 years of follow up, the incidences of death, HF, thromboembolism, and major bleeding were significantly higher among patients with than without anemia. In addition, the incidence of death or HF was significantly higher in Group 3 than in Groups 1 and 2. Multivariate analysis revealed no anemia or improvement in anemia in 1 year as an independent predictor for a favorable prognosis for cardiovascular death and HF.

CONCLUSIONS

Recovery from anemia may be associated with a favorable clinical course of AF.

Meta-analysis of Pulsed Field Ablation Versus Thermal Ablation for Pulmonary Vein Isolation in AF: A Broad Overview Focusing on Efficacy, Safety and Outcomes

The recently established non-thermal, single-shot pulsed field ablation (PFA) is a potential tool for achieving rapid pulmonary vein isolation (PVI) to cause cell death by electroporation, yet data regarding this state-of-the-art technology remain sparse. In this meta-analysis, we included 3,857 patients from 20 studies. There was no significant difference in AF recurrence between the PFA and control groups. Subgroup analysis showed that additional ablation beyond PVI has a similar rate of AF recurrence to PVI alone (10% versus 13%, respectively). PVI durability was achieved in 83% (mean), 95% CI [65-99%] of the PFA group and in 79% (mean), 95% CI [60-98%] of the control group, with no significant difference in the rate of PVI durability between the two groups. The PFA group had considerably reduced procedure duration, but not fluoroscopy time. No statistically significant differences in periprocedural complications were observed. PFA is associated with shorter procedural time than thermal ablation. Cardiac complications were uncommon and mainly reversible in both the PFA and control groups.

Predicting Adverse Outcomes Following Catheter Ablation Treatment for Atrial Flutter/Fibrillation

BACKGROUND & AIM

To develop prognostic survival models for predicting adverse outcomes after catheter ablation treatment for non-valvular atrial fibrillation (AF) and/or atrial flutter (AFL).

METHODS

We used a linked dataset including hospital administrative data, prescription medicine claims, emergency department presentations, and death registrations of patients in New South Wales, Australia. The cohort included patients who received catheter ablation for AF and/or AFL. Traditional and deep survival models were trained to predict major bleeding events and a composite of heart failure, stroke, cardiac arrest, and death.

RESULTS

Out of a total of 3,285 patients in the cohort, 177 (5.3%) experienced the composite outcome-heart failure, stroke, cardiac arrest, death-and 167 (5.1%) experienced major bleeding events after catheter ablation treatment. Models predicting the composite outcome had high-risk discrimination accuracy, with the best model having a concordance index >0.79 at the evaluated time horizons. Models for predicting major bleeding events had poor risk discrimination performance, with all models having a concordance index <0.66. The most impactful features for the models predicting higher risk were comorbidities indicative of poor health, older age, and therapies commonly used in sicker patients to treat heart failure and AF and AFL.

DISCUSSION

Diagnosis and medication history did not contain sufficient information for precise risk prediction of experiencing major bleeding events. Predicting the composite outcome yielded promising results, but future research is needed to validate the usefulness of these models in clinical practice.

CONCLUSIONS

Machine learning models for predicting the composite outcome have the potential to enable clinicians to identify and manage high-risk patients following catheter ablation for AF and AFL proactively.

Long-term Patient and Health Service Outcomes of Ablation and Antiarrhythmic Drugs in Atrial Fibrillation: A Comparative Systematic Review

Atrial fibrillation (AF) is a prevalent problem worldwide and a common cause of hospitalization, poor quality of life, and increased mortality. Although several treatments are used, the use of ablation and antiarrhythmic drug therapy has increased in the past decade. However, debate continues on the most suitable option for heart rhythm control in patients. Previous studies have largely focused on short-term outcome effects of these treatments. This systematic review aims to determine the effect of ablation compared to antiarrhythmic drugs for AF on long-term patient and health service outcomes of mortality, hospitalization, and quality of life. Three databases were systematically searched-studies were included if they reported long-term outcomes of more than 12 months comparing the 2 treatments. Title and abstract screening and subsequent full-text screening was done by 2 reviewers. Data were extracted from the final studies identified. The details of the search were recorded according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses report. A total of 2224 records were identified. After removing duplicates and screening the titles and abstracts, 68 records required full-text screening. Finally, 12 papers were included in the analysis. Eight studies reported mortality indicating ablation was superior, 2 studies reported hospitalization with opposing outcomes, and 5 quality of life studies indicating ablation was a better treatment. In studies assessing long-term outcomes, beyond 12 months, following ablation or rhythm control drugs for AF, most found a lower risk of death and greater improvement in quality of life in the ablation group.

Castelino R, Inglis SC, Davidson PM, Ferguson C. Direct oral anticoagulant use in hospitalized patients with atrial fibrillation across body mass index categories: design and rationale for a retrospective cohort study

Background

Atrial fibrillation (AF) and obesity are common conditions globally; yet, there remains suboptimal pharmacological management contributing to high rates of hospitalization in patients with AF. The altered pathophysiology of both obese and underweight individuals may influence the pharmacology of medications, including those used to manage AF. This, in turn, increases the risk of adverse events and impacts patient risk for stroke and rehospitalization. Despite the well-established complications of obesity, research investigating the relationship between obesity and AF is scant.

Objectives

The primary aim of this study is to describe cardiovascular-related hospitalization in AF patients according to BMI categories. A secondary aim is to describe anticoagulant and antiarrhythmic prescribing practice patterns in patients with AF, according to the BMI category.

Design

A retrospective, exploratory descriptive observational cohort study, using routinely collected electronic medical record data from five public hospitals within a single health district, with a population dominantly that is culturally and linguistically diverse, and has a low socioeconomic status.

Methods and analysis

Data extraction will include a 24-month period (January 2017 to December 2018) with a 12-month follow-up. All adult (⩾18 years) patients at discharge diagnosed with AF, prescribed any oral anticoagulant and/or oral rate/rhythm control agent, will be eligible for inclusion.

Ethics and dissemination

Ethics approval from the health district and the University of Wollongong has been granted. Findings will seek to demonstrate associations between management strategies and patient outcomes, as well as describe patterns of acute care management from prescribers. These data will be used to inform and generate hypotheses for large-scale studies examining the impact of body weight on anticoagulation prescribing at national and global scales.

Factors influencing blood pressure control in patients with atrial fibrillation and hypertension in Australian primary care

OBJECTIVE

This study explored factors that may influence blood pressure (BP) control in patients with atrial fibrillation (AF) with hypertension.

METHODS

Cross-sectional retrospective analysis of the MedicineInsight database which includes de-identified electronic health records from general practices (GPs) across Australia. BP control was assessed in patients with diagnosed AF and hypertension (controlled BP defined as <140/90 mm Hg). We explored BP control, factors influencing BP control and likelihood of receiving guideline-recommended treatment.

RESULTS

34 815 patients with AF and hypertension were included; mean age was 76.9 (10.2 SD) years and 46.2% were female. 38.0% had uncontrolled BP. Women (OR 0.72; 95% CI 0.68, 0.76; p<0.001) and adults ≥75 years (OR 0.78; 95% CI 0.70, 0.86; p<0.001) were less likely to have controlled BP. Greater continuity of care (CoC; that is, visits with the same clinician) and having frequent GP visits were associated with higher odds of controlled BP (model 1: CoC, OR 1.29; 95% CI 1.20, 1.40, p<0.001; GP visits, OR 1.71; 95% CI 1.58, 1.85, p<0.001) and a greater likelihood of being prescribed ≥2 types of BP-lowering medicines (model 2: CoC, OR 1.12; 95% CI 1.03, 1.23; p=0.011; GP visits, OR 1.80; 95% CI 1.63, 1.98; p<0.001).

CONCLUSIONS

Uncontrolled BP was more likely in women and adults ≥75 years. Patients who had frequent GP visits with the same clinician were more likely to have BP controlled and receive guideline-recommended antihypertensive treatment. This suggests that targeting these primary care factors could potentially improve BP control and subsequently reduce stroke risk in patients with AF.

The validity and reliability of Indonesian version of atrial fibrillation effect on quality of life (AFEQT) questionnaire for atrial fibrillation patients

BACKGROUND

More than 60% of patients with atrial fibrillation (AF) have a significant health-related quality of life (HRQoL) impairment. HRQoL, a patient-reported outcome (PRO), has become an important endpoint to assess treatment success in AF patients. The Atrial Fibrillation Effect on Quality of Life (AFEQT) questionnaire is an AF-specific HRQoL tool shown to be feasible, reliable, and valid, with translations in various languages. Since this questionnaire has never been translated or validated in Indonesian, we aimed to determine the validity and reliability of the Indonesian version of the AFEQT questionnaire for AF patients.

RESULTS

This cross-sectional, observational study was conducted in the Integrated Cardiovascular Service Polyclinic, Cipto Mangunkusumo Hospital, Indonesia, from December 2021 to March 2022. A total of 30 participants were recruited for cross-cultural adaptation process, which consisted of translation and adaptation process, and a total of 102 participants were consecutively recruited to participate in the validation process, which consisted of validity test (construct validity) and reliability tests (internal consistency and test-retest). The retest was conducted within a 1-2-week interval after the baseline assessment, by analyzing the intraclass correlation coefficient (ICC). The construct validity was determined by multitrait scaling analysis, and the convergent and divergent validity was compared to SF-36 domains. Multitrait scaling analysis revealed that all items in the Indonesian version of the AFEQT questionnaire had a strong negative correlation towards their respective domains (r -0.639--0.960). For convergent and divergent validity, AFEQT domains had weak to strong positive correlations to all SF-36 domains (r 0.338-0.693). This questionnaire also had acceptable internal consistency (Cronbach's α for overall score: 0.947; Domains: Symptoms: 0.818, Daily Activities: 0.943, Treatment Concern: 0.894, and Treatment Satisfaction: 0.865), as well as moderate-to-good test-retest reliability (0.521-0.828).

CONCLUSIONS

The Indonesian version of the AFEQT questionnaire has good validity and reliability for assessing quality of life of atrial fibrillation patients in Indonesia.

Patterns of oral anticoagulant use and outcomes in Asian patients with atrial fibrillation: a post-hoc analysis from the GLORIA-AF Registry

Background

Previous studies suggested potential ethnic differences in the management and outcomes of atrial fibrillation (AF). We aim to analyse oral anticoagulant (OAC) prescription, discontinuation, and risk of adverse outcomes in Asian patients with AF, using data from a global prospective cohort study.

Methods

From the GLORIA-AF Registry Phase II-III (November 2011-December 2014 for Phase II, and January 2014-December 2016 for Phase III), we analysed patients according to their self-reported ethnicity (Asian vs. non-Asian), as well as according to Asian subgroups (Chinese, Japanese, Korean and other Asian). Logistic regression was used to analyse OAC prescription, while the risk of OAC discontinuation and adverse outcomes were analysed through Cox-regression model. Our primary outcome was the composite of all-cause death and major adverse cardiovascular events (MACE). The original studies were registered with ClinicalTrials.gov, NCT01468701, NCT01671007, and NCT01937377.

Findings

34,421 patients were included (70.0 ± 10.5 years, 45.1% females, 6900 (20.0%) Asian: 3829 (55.5%) Chinese, 814 (11.8%) Japanese, 1964 (28.5%) Korean and 293 (4.2%) other Asian). Most of the Asian patients were recruited in Asia (n = 6701, 97.1%), while non-Asian patients were mainly recruited in Europe (n = 15,449, 56.1%) and North America (n = 8378, 30.4%). Compared to non-Asian individuals, prescription of OAC and non-vitamin K antagonist oral anticoagulant (NOAC) was lower in Asian patients (Odds Ratio [OR] and 95% Confidence Intervals (CI): 0.23 [0.22-0.25] and 0.66 [0.61-0.71], respectively), but higher in the Japanese subgroup. Asian ethnicity was also associated with higher risk of OAC discontinuation (Hazard Ratio [HR] and [95% CI]: 1.79 [1.67-1.92]), and lower risk of the primary composite outcome (HR [95% CI]: 0.86 [0.76-0.96]). Among the exploratory secondary outcomes, Asian ethnicity was associated with higher risks of thromboembolism and intracranial haemorrhage, and lower risk of major bleeding.

Interpretation

Our results showed that Asian patients with AF showed suboptimal thromboembolic risk management and a specific risk profile of adverse outcomes; these differences may also reflect differences in country-specific factors. Ensuring integrated and appropriate treatment of these patients is crucial to improve their prognosis.

Funding

The GLORIA-AF Registry was funded by Boehringer Ingelheim GmbH.

Atrial fibrillation and stroke prevention: 25 years of research at EP Europace journal

Stroke prevention in patients with atrial fibrillation (AF) is one pillar of the management of this common arrhythmia. Substantial advances in the epidemiology and associated pathophysiology underlying AF-related stroke and thrombo-embolism are evident. Furthermore, the introduction of the non-vitamin K antagonist oral anticoagulants (also called direct oral anticoagulants) has clearly changed our approach to stroke prevention in AF, such that the default should be to offer oral anticoagulation for stroke prevention, unless the patient is at low risk. A strategy of early rhythm control is also beneficial in reducing strokes in selected patients with recent onset AF, when compared to rate control. Cardiovascular risk factor management, with optimization of comorbidities and attention to lifestyle factors, and the patient's psychological morbidity are also essential. Finally, in selected patients with absolute contraindications to long-term oral anticoagulation, left atrial appendage occlusion or exclusion may be considered. The aim of this state-of-the-art review article is to provide an overview of the current status of AF-related stroke and prevention strategies. A holistic or integrated care approach to AF management is recommended to minimize the risk of stroke in patients with AF, based on the evidence-based Atrial fibrillation Better Care (ABC) pathway, as follows: A: Avoid stroke with Anticoagulation; B: Better patient-centred, symptom-directed decisions on rate or rhythm control; C: Cardiovascular risk factor and comorbidity optimization, including lifestyle changes.

Practices, beliefs, and attitudes of clinicians in prescribing direct oral anticoagulants for obese adults with atrial fibrillation: a qualitative study

BACKGROUND

Atrial fibrillation (AF) and obesity affect over 60 and 650 million people, respectively.

AIM

This study aimed to explore clinician practices, beliefs, and attitudes towards the use of direct oral anticoagulants (DOACs) in obese adults (BMI ≥ 30 kg/m2) with AF.

METHOD

Semi-structured interviews via video conference were conducted with multidisciplinary clinicians from across Australia, with expertise in DOAC use in adults with AF. Clinicians were invited to participate using purposive and snowball sampling techniques. Data were analysed in NVIVO using thematic analysis.

RESULTS

Fifteen clinicians including cardiologists (n = 5), hospital and academic pharmacists (n = 5), general practitioners (n = 2), a haematologist, a neurologist and a clinical pharmacologist participated. Interviews were on average 31 ± 9 min. Key themes identified were: Health system factors in decision-making Disparities between rural and metropolitan geographic areas, availability of health services, and time limitations for in-patient decision-making, were described; Condition-related factors in decision-making Clinicians questioned the significance of obesity as part of decision-making due to the practical limitations of dose modification, and the rarity of the extremely obese cohort; Decision-making in the context of uncertainty Clinicians reported limited availability, reliability and awareness of primary evidence including limited guidance from clinical guidelines for DOAC use in obesity.

CONCLUSION

This study highlights the complexity of decision-making for clinicians, due to the limited availability, reliability and awareness of evidence, the intrinsic complexity of the obese cohort and limited guidance from clinical guidelines. This highlights the urgent need for contemporary research to improve the quality of evidence to guide informed shared decision-making.

Atrial fibrillation: primary prevention, secondary prevention, and prevention of thromboembolic complications: part 1

Atrial fibrillation (AF), is the most common sustained cardiac arrhythmia. It was once thought to be benign as long as the ventricular rate was controlled, however, AF is associated with significant cardiac morbidity and mortality. Increasing life expectancy driven by improved health care and decreased fertility rates has, in most of the world, resulted in the population aged ≥65 years growing more rapidly than the overall population. As the population ages, projections suggest that the burden of AF may increase more than 60% by 2050. Although considerable progress has been made in the treatment and management of AF, primary prevention, secondary prevention, and prevention of thromboembolic complications remain a work in progress. This narrative review was facilitated by a MEDLINE search to identify peer-reviewed clinical trials, randomized controlled trials, meta-analyses, and other clinically relevant studies. The search was limited to English-language reports published between 1950 and 2021. Atrial fibrillation was searched via the terms primary prevention, hyperthyroidism, Wolff-Parkinson-White syndrome, catheter ablation, surgical ablation, hybrid ablation, stroke prevention, anticoagulation, left atrial occlusion and atrial excision. Google and Google scholar as well as bibliographies of identified articles were reviewed for additional references. In these two manuscripts, we discuss the current strategies available to prevent AF, then compare noninvasive and invasive treatment strategies to diminish AF recurrence. In addition, we examine the pharmacological, percutaneous device and surgical approaches to prevent stroke as well as other types of thromboembolic events.

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.

Prevalence of atrial fibrillation in a regional Victoria setting, findings from the crossroads studies (2001-2003 and 2016-2018)

OBJECTIVE

To estimate the prevalence of atrial fibrillation (AF) in regional Victoria at two time points (2001-2003 and 2016-2018), and to assess the use of electrocardiogram rhythm strips in a rural, community-based study for AF investigation.

DESIGN

Repeated cross-sectional design involving survey of residents of randomly selected households and a clinic. Predictors of AF were assessed using Firth penalised logistic regression, as appropriate for rare events.

SETTING

Goulburn Valley, Victoria.

PARTICIPANTS

Household residents aged ≥16 years. Non-pregnant participants aged 18+ were eligible for the clinic.

MAIN OUTCOME MEASURES

Atrial fibrillation by 12 lead electrocardiogram (earlier study) or electrocardiogram rhythm strip (AliveCor® device) (recent study).

RESULTS

The age standardised prevalence of AF was similar between the two studies (1.6% in the 2001-2003 study and 1.8% in the 2016-2018 study, 95% confidence interval of difference -0.010, 0.014, p = 0.375). The prevalence in participants aged ≥65 years was 3.4% (1.0% new cases) in the recent study. Predictors of AF in the earlier study were male sex, older age and previous stroke, while in the recent study they were previous stroke and self-reported diabetes. AliveCor® traces were successfully classified by the in-built algorithm (91%) vs physician (100%).

CONCLUSION

The prevalence of AF among community-based participants in regional Victoria was similar to predominantly metropolitan-based studies, and was unchanged over time despite increased rates of risk factors. Electrocardiogram rhythm strip investigation was successfully utilised, and particularly benefited from physician overview.

Evaluation of the Paradoxical Association Between Lipid Levels and Incident Atrial Fibrillation According to Statin Usage: A Nationwide Cohort Study

Objective

Higher levels of total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) are associated with a lower risk of atrial fibrillation (AF). Statin use might exert confounding effects on the paradoxical associations; however, the relationships that distinguish statin users from non-users have not been thoroughly evaluated.

Methods

From the Korean National Health Insurance Database, we included 9,778,014 adults who underwent a health examination in 2009. The levels of TC and LDL-C at the health examination were categorized into quartile values of the total study population. We grouped the study population into statin users and non-users and investigated the associations between TC, LDL-C, and the risk of incident AF.

Results

Of the total population, 867,336 (8.9%) were taking statins. During a mean follow-up of 8.2 years, inverse associations of TC - AF and LDL-C - AF were observed; higher levels of TC and LDL-C were associated with the lower risk of AF in the total population. Overall, statin users showed higher AF incidence rate than non-users, but the inverse associations of TC - AF and LDL-C - AF were consistently observed irrespective of statin usage; adjusted hazard ratio with 95% confidence interval was 0.81 (0.79-0.84) for statin users and 0.81 (0.80-0.83) for non-users in the highest TC quartile, and 0.84 (0.82-0.87) for statin users and 0.85 (0.84-0.86) for non-users in the highest LDL-C quartile (all p<0.001).

Conclusion

The paradoxical relationship between lipid levels (TC and LDL-C) and the risk of AF remains consistent in both statin users and non-users.

Global disparities in arrhythmia care: Mind the gap

Delivery of comprehensive arrhythmia care requires the simultaneous presence of many resources. These include complex hospital infrastructure, expensive implantable equipment, and expert personnel. In many low- and middle-income countries (LMICs), at least 1 of these components is often missing, resulting in a gap between the demand for arrhythmia care and the capacity to supply care. In addition to this treatment gap, there exists a training gap, as many clinicians in LMICs have limited access to formal training in cardiac electrophysiology. Given the progressive increase in the burden of cardiovascular diseases in LMICs, these patient care and clinical training gaps will widen unless further actions are taken to build capacity. Several strategies for building arrhythmia care capacity in LMICs have been described. Medical missions can provide donations of both equipment and clinical expertise but are only intermittently present and therefore are not optimized to provide the longitudinal support needed to create self-sustaining infrastructure. Use of donated or reprocessed equipment (eg, cardiac implantable electronic devices) can reduce procedural costs but does not address the need for infrastructure, including diagnostics and expert personnel. Collaborative efforts involving multiple stakeholders (eg, professional organizations, government agencies, hospitals, and educational institutions) have the potential to provide longitudinal support of both patient care and clinician education in LMICs.

Prognosis and treatment of atrial fibrillation in Asian cities: 1-year review of the Asia-Pacific Heart Rhythm Society Atrial Fibrillation Registry

AIMS

The aim of this study is to describe the implementation of the current guidance for stroke prevention and treatment option in atrial fibrillation (AF) and to evaluate mortality and morbidity in relation to therapeutic decisions, including persistence with treatment at 1 year in Asia-Pacific regions.

METHODS AND RESULTS

We recruited 4664 patients consecutive in- and outpatients with AF who presented to cardiologists in five countries under the Asia-Pacific Heart Rhythm Society (APHRS) in whom 1-year follow-up was completed for 4003 (65.5% male; mean age 68.5 years). Oral anticoagulant (OAC) use remained high, 77% at follow-up, including 17% prescribed a vitamin K antagonist (VKA) and 60% a non-VKA oral anticoagulant (NOAC). At 1-year follow-up, 93% and 88% remained on a VKA or NOAC, respectively. With good adherence to OAC therapy, 1-year mortality was only 2.7%. Most deaths were non-cardiovascular (72.3%) and the 1-year incidence of stroke/transient ischaemic events (TIA) was low (<1%). Hospital readmissions were common for non-cardiovascular cases and atrial tachyarrhythmias. On multivariate analysis, independent baseline predictors of mortality and/or stroke/TIA/peripheral embolism were age, previous heart failure for >12 months, and malignancy. Independent predictors of mortality were age, chronic obstructive pulmonary disease, malignancy, and diuretic use. AF as a primary presentation was predictive of lower mortality and/or stroke/TIA/peripheral embolism as well as mortality.

CONCLUSION

In this 1-year analysis of the APHRS-AF registry, overall OAC use and persistence were high and were associated with low 1-year cardiovascular mortality and morbidity, but mortality and morbidity related to non-cardiovascular causes were high in AF patients, particularly from malignancy and pneumonia.

Sex and ethnicity modified high 1-year mortality in patients in Singapore with newly diagnosed atrial fibrillation

INTRODUCTION

We investigated sex and ethnic differences in the incidence, clinical characteristics and 1-year mortality of patients with newly diagnosed AF in a multi-ethnic population.

METHOD

This retrospective cohort study of patients diagnosed with AF from 2008 to 2015 was based on medical claims, casemix and subvention data submitted to the Ministry of Health. Patients with AF were matched with controls without AF for age (3-year bands), sex and ethnicity, and categorised as middle-aged (45-64 years) or elderly (≥65 years) among major ethnic groups in Singapore (Chinese, Malay and Indian).

RESULTS

Among 40,602 adults with AF (elderly 74%), Malays had the highest age-standardised incidence rate of AF, followed by Chinese and Indians; and the rate was higher in men. Despite having the worst cardiovascular risk profile, Indians had the lowest prevalence and incidence of AF. The 1-year mortality rate after newly diagnosed AF was 22-26 deaths per 100 people. Newly diagnosed AF was independently associated with increased 1-year all-cause mortality among middle-aged (adjusted odds ratio [AOR] 9.08, 95% confidence interval [CI] 7.36-11.20) and elderly adults (AOR 3.60, 95% CI 3.40-3.80) compared with those without AF. Sex differences in mortality among patients with AF were limited to elderly adults (men: AOR 1.17, 95% CI 1.11-1.24), while Indians were associated with a 30% increased odds of mortality compared with Chinese regardless of age (middle-aged: AOR 1.27, 95% CI 1.09-1.548 elderly: AOR 1.33, 95% CI 1.22-1.45).

CONCLUSION

Variations in incidence, clinical profile and 1-year mortality of patients with AF in a nationwide cohort were influenced by sex and ethnicity. Newly diagnosed AF portends a worse prognosis and is a marker of high mortality within the first year.

Risk Factors of Haematoma Formation Following Cardiac Implantable Electronic Device Procedures

PURPOSE

A single-centre cohort of 2,100 adults who consecutively underwent cardiac implantable electronic device procedures were retrospectively analysed to identify and quantify risk factors of perioperative pocket haematoma formation.

RESULTS

Dual antiplatelet therapy was significantly associated with increased odds of haematoma formation (OR 11.7 for aspirin and clopidogrel, OR 11.8 for aspirin and ticagrelor and OR 104 for aspirin and prasugrel, p<0.05) on multivariate binomial logistic regression analysis. Aspirin monotherapy was also associated with increased bleeding risk (OR 3.02, p<0.01). Direct oral anticoagulants and warfarin were also each associated with increased odds of haematoma formation although to a lesser extent than dual anti platelet therapy (DAPT). Amongst oral anticoagulants, apixaban was associated with the lowest bleeding risk (OR 2.59, p=0.03) whilst dabigatran was associated with the highest (OR 3.81, p=0.04). There was a significant incremental reduction in bleeding risk by 8% per 10x10³/μL increase in platelet count.

CONCLUSION

DAPT was associated with increased odds of pocket haematoma formation following cardiovascular implantable electronic device (CIED) procedure. This likelihood was higher than with oral anticoagulation therapy. Timely medication reconciliation of P2Y₁₂ inhibitors according to guidelines is important to avoid post-procedural bleeding complications. Perioperative policies which account for the half-life of withheld anticoagulant agents may help reduce the haematoma risk.

Relationship between serum growth differentiation factor 15, fibroblast growth factor-23 and risk of atrial fibrillation: A systematic review and meta-analysis

Background and objective

Growth differentiation factor-15 (GDF-15) and fibroblast growth factor-23 (FGF-23) are considered predictors of the incidence of cardiovascular diseases. The present meta-analysis aimed to elucidate the associations between GDF-15 and FGF-23 in the risk of atrial fibrillation (AF).

Methods

An electronic search was conducted in the Cochrane Library, PubMed, and Embase databases from inception until February 27, 2021. The study protocol was registered in the PROSPERO database (CRD42020182226).

Results

In total, 15 studies that enrolled 36,017 participants were included. Both serum FGF-23 and GDF-15 were elevated in patients with AF. Analysis of categorical variables showed higher serum FGF-23 levels were associated with an increased risk of AF [relative risk (RR) = 1.28, 95% confidence interval (CI): 1.05–1.56]. In contrast, this association was not found with GDF-15 (RR = 0.91, 95% CI: 0.20–4.04). In dose-response analysis, a linear positive association was noted between serum FGF-23 levels and the risk of AF (P nonlinear = 0.9507), with a RR elevation of 7% for every 20 pg/ml increase in the serum FGF-23 levels (95% CI: 1.02–1.13). No remarkable relationship was found between serum GDF-15 levels and the risk of AF, and the overall RR for the association between a 100 ng/L increment in GDF-15 levels and AF was 1.01 (95% CI: 0.998–1.02).

Conclusion

Our study showed a positive linear correlation between serum FGF-23 levels and the risk of AF. However, no significant association was found between GDF-15 and the risk of AF. Further studies are warranted to clarify whether serum FGF-23 levels may be considered in predicting the risk of AF.

Systematic Review Registration:http:www.york.ac.uk/inst/crd, identifier CRD42020182226.

Effect of Dronedarone in the Treatment of Atrial Fibrillation in the Asian Population: Post Hoc Analysis of the ATHENA Trial

PURPOSE

Limited data are available on the impact of dronedarone treatment in Asian patients with atrial fibrillation (AF) or atrial flutter (AFL). This post hoc analysis evaluated the efficacy and safety of dronedarone compared with placebo in populations from Asian and non-Asian regions randomized in the ATHENA trial (A Placebo-Controlled, Double-blind, Parallel Arm Trial to Assess the Efficacy of Dronedarone 400 mg BID for the Prevention of CV Hospitalization or Death From Any Cause in Patients With AF/AFL).

METHODS

Time to first hospitalization for cardiovascular events or death from any cause (primary outcome) and time to first AF/AFL event recurrence (secondary outcome) were analyzed by Kaplan-Meier curves and Cox proportional hazards regression.

FINDINGS

The risk of experiencing the primary composite outcome was significantly lower in the dronedarone-treated patients in both the Asian (hazard ratio = 0.541; 95% CI, 0.320-0.914]) and non-Asian (hazard ratio = 0.768; 95% CI, 0.696-0.848) populations than in the placebo-treated patients. The median time to the first AF/AFL event recurrence was longer in the dronedarone-treated population than in the placebo-treated populations: 183 vs 92 days (P = 0.165) in the Asian population and 534 vs 196 days (P < 0.001) in the non-Asian population. Treatment-emergent adverse events in Asian (81.2% vs 78.4%) and non-Asian (71.4% vs 68.7%) populations and serious treatment-emergent adverse events in Asian (14.3% vs 15.7%) and non-Asian (20.3% vs 21.5%) patients were comparable in patients taking dronedarone compared with those taking placebo.

IMPLICATION

Efficacy and tolerability of dronedarone were consistent in the Asian population compared with the non-Asian population in the ATHENA trial. These finding may aid Asian health care professionals to select the appropriate first-line treatment for Asian patients with AF/AFL.

Elevated levels of body mass index and waist circumference, but not high variability, are associated with an increased risk of atrial fibrillation

BACKGROUND

Although obesity has been associated with risk of atrial fibrillation (AF), the associations of variability of obesity measures with AF risk are uncertain, and longitudinal studies among Chinese population are still lacking. We aimed to evaluate the impacts of obesity and variability of body mass index (BMI) and waist circumference (WC) on the risk of atrial fibrillation (AF) in a large Chinese cohort study.

METHODS

A total of 44,135 participants of the Kailuan Study who were free of cancer and cardiovascular disease and underwent three consecutive surveys from 2006 to 2010 were followed for incident AF until 2020. Average BMI and WC over time and variability were calculated. Cox proportional hazards regression models were used to assess hazard ratios (HRs) and 95% confidence intervals (CIs) for the associations of obesity and variability in BMI and WC with AF risk.

RESULTS

During a mean follow-up of 9.68 years, there were 410 cases of incident AF. In multivariable-adjusted models, compared with normal BMI/WC, individuals with general obesity and abdominal obesity had increased risk of AF, with corresponding HRs of 1.73 (95% CI: 1.31-2.30) and 1.38 (95% CI: 1.11-1.60), respectively. The short-term elevation in AF risk persisted for the obese even after adjustment for updated biologic intermediaries and weight. Variability in BMI and WC were not associated with the risk of AF. The restricted cubic spline models indicated significant linear relationships between levels of WC and BMI and risk of AF.

CONCLUSIONS

Elevated levels of BMI and WC were associated with an increased risk of AF, whereas variability in BMI and WC were not. Therefore, achieving optimal levels of BMI and WC could be valuable in AF prevention.

Mechanism of Action of Zhi Gan Cao Decoction for Atrial Fibrillation and Myocardial Fibrosis in a Mouse Model of Atrial Fibrillation: A Network Pharmacology-Based Study

Atrial fibrillation (AF), a commonly seen cardiac disease without optimal curative treatment option, is usually treated by traditional Chinese medicine in China. The Zhi-Gan-Cao decoction (ZGCD) is an alternative medicine for clinical use and has definitive effects. It remains to be defined regarding the specific components and related mechanisms of ZGCD for the treatment of AF. We determined the primary constituents and major targets of the herbs in ZGCD using the TCMSP, HERB, and BATMAN-TCM databases. The UniProt databank database amended and combined the prospective names to supply objective data and records. Every target connected to AF was generated using the GeneCards databank, Drugbank database, TTD, Disgenet database, and OMIM. After identifying possible common targets between ZGCD and AF, the interface network illustration “ZGCD component-AF-target” was created using Cytoscape. We obtained 175 constituents and 839 targets for seven herbal drug categories in the ZGCD and identified 1008 targets of AF. After merging and removing repetitions, 136 collective targets between the ZGCD and AF were removed using the Cytoscape system. These renowned targets were generated from 38 suitable components from among the 157 components. GO enhancement examination and KEGG enrichment analysis by Metascape identified the close connection between the critical target genes and 20 signaling pathways. Then, we injected isoproterenol subcutaneously into the mouse and gave gavage with roasted licorice soup. Two weeks later, mouse were processed and sampled for testing. The results of HE and Masson staining showed that ZGCD effectively alleviated the degree of myocardial fibrosis. As indicated by qRT-PCR and Western blotting, ZGCD significantly reduced COL1A1, COL1A2, COL3A1, and TGF-β1 in myocardial fibrotic tissue to reduce myocardial fibrosis and treat AF by interfering with the expression of COL1A1, COL1A2, COL3A1, and TGF-β1 in myocardial tissue. ZGCD may treat AF by lowering the degree of myocardial fibrosis.

Comparison of 2 Smart Watch Algorithms for Detection of Atrial Fibrillation and the Benefit of Clinician Interpretation: SMART WARS Study

BACKGROUND

Smart watches and wearable technology capable of heart rhythm assessment have increased in use in the general population. The Apple Watch Series 4 (AW4) and KardiaBand (KB) are devices capable of obtaining single-lead electrocardiographic recordings, presenting a novel opportunity for the detection of paroxysmal arrhythmias.

OBJECTIVES

The aim of this study was to assess the diagnostic utility of the AW4 and KB in an elderly outpatient population.

METHODS

Consecutive recordings were taken from patients attending cardiology outpatient clinic from the AW4 and KB concurrently with 12-lead electrocardiography. Automated diagnoses and blinded single-lead electrocardiographic tracing interpretations by 2 cardiologists were analyzed. Analysis was also conducted to assess the effect of combined device and clinician interpretation.

RESULTS

One hundred twenty-five patients were prospectively recruited (mean age 76 ± 7 years, 62% men). The accuracy of the automated rhythm assessment was higher with the KB than the AW4 (74% vs 65%). For the detection of atrial fibrillation, the sensitivity and negative predictive value of the KB were 89% and 97%, respectively, and of the AW4 were 19% and 82%, respectively. Using hybrid automated and clinician interpretation, the overall accuracy of the KB and AW4 was 91% and 87%, respectively.

CONCLUSIONS

The KB automated algorithm outperformed the AW4 in its accuracy and sensitivity for detecting atrial fibrillation in the outpatient setting. Clinician assessment of the single-lead electrocardiogram improved accuracy. These findings suggest that although these devices' tracings are of sufficient quality, automated diagnosis alone is not sufficient for making clinical decisions about atrial fibrillation diagnosis and management.

An Observational Study of Clinical and Health System Factors Associated With Catheter Ablation and Early Ablation Treatment for Atrial Fibrillation in Australia

OBJECTIVE

To investigate clinical and health system factors associated with receiving catheter ablation (CA) and earlier ablation for non-valvular atrial fibrillation (AF).

METHODS

We used hospital administrative data linked with death registrations in New South Wales, Australia for patients with a primary diagnosis of AF between 2009 and 2017. Outcome measures included receipt of CA versus not receiving CA during follow-up (using Cox regression) and receipt of early ablation (using logistic regression).

RESULTS

Cardioversion during index admission (hazard ratio [HR] 1.96; 95% CI 1.75-2.19), year of index admission (HR 1.07; 1.07; 95% CI 1.05-1.10), private patient status (HR 2.65; 95% CI 2.35-2.97), and living in more advantaged areas (HR 1.18; 95% CI 1.13-1.22) were associated with a higher likelihood of receiving CA. A history of congestive heart failure, hypertension, diabetes, and myocardial infarction were associated with a lower likelihood of receiving CA. Private patient status (odds ratio [OR] 2.04; 95% CI 1.59-2.61), cardioversion during index admission (OR 1.25; 95% CI 1.0-1.57), and history of diabetes (OR 1.6; 95% CI 1.06-2.41) were associated with receiving early ablation.

CONCLUSIONS

Beyond clinical factors, private patients are more likely to receive CA and earlier ablation than their public counterparts. Whether the earlier access to ablation procedures in private patients is leading to differences in outcomes among patients with atrial fibrillation remains to be explored.

Anemia and iron deficiency in patients with atrial fibrillation

Atrial fibrillation (AF) is the most common cardiac tachyarrhythmia and has a rising global prevalence. Given the increasing burden of AF-related symptoms and complications, new approaches to management are required. Anemia and iron deficiency are common conditions in patients with AF. Furthermore, emerging evidence suggests that the presence of anemia may be associated with worse outcome in these patients. The role of anemia and iron deficiency has been extensively explored in other cardiovascular states, such as heart failure and ischemic heart disease. In particular, the role of iron repletion amongst patients with heart failure is now an established treatment modality. However, despite the strong bidirectional inter-relationship between AF and heart failure, the implications of anemia and iron-deficiency in AF have been scarcely studied. This area is of mechanistic and clinical relevance given the potential that treatment of these conditions may improve symptoms and prognosis in the increasing number of individuals with AF. In this review, we summarise the current published literature on anemia and iron deficiency in patients with AF. We discuss AF complications such as stroke, bleeding, and heart failure, in addition to AF-related symptoms such as exercise intolerance, and the potential impact of anemia and iron deficiency on these. Finally, we summarize current research gaps on anemia, iron deficiency, and AF, and underscore potential research directions.

Arterial stiffness and atrial fibrillation: A review

Arterial stiffness has been investigated as part of the physiopathology of arterial hypertension since the 1970s. Its role in increasing the "pulsatile load" imposed over the Left Ventricle (LV) has been intensely studied recently and has helped in understanding the mechanisms of Atrial Fibrillation (AF) in hypertensive patients. This paper aims to review the main evidence on this issue and establish possible mechanisms involved in the development of AF in patients with arterial stiffness. A PubMed search was performed, and selected articles were searched for references focusing on this topic. In the long term, lower blood pressure levels allow for arterial wall remodeling, leading to a lower stiffness index. To this day, however, there are no available treatments that directly promote the lowering of arterial wall stiffness. Most classes of anti-hypertensive drugs ‒ with stronger evidence for beta-blockers and diuretics ‒ could be effective in reducing arterial stiffness. There is strong evidence demonstrating an association between arterial stiffness and AF. New studies focusing on arterial stiffness and pre-fibrillatory stages would strengthen this causality relation.

Prevalence and characteristics of atrial fibrillation in Makassar city population: A telemedicine study

OBJECTIVE

Atrial fibrillation (AF) is one of the most commonly occurring arrhythmias and a major modifiable risk factor of stroke, especially in women. The incidence of AF in Indonesia is not well-characterized yet. This is a community-based study to determine the prevalence and characteristics of AF in the Makassar city population.

METHOD

Standard ECG recording showing atrial fibrillation obtained between January 1, 2014 and September 31, 2018 from Telemedicine Study Center in Hasanuddin University Hospital were collected in form of portable document format (pdf) and were analyzed. ECG with incomplete interpretation and/or epidemiological data were excluded. ECG interpretation and analysis were performed by the first author as an electrophysiologist (MA). Epidemiological data, heart rate, P wave amplitude, QRS axis, QRS complex duration and configuration, QRS rate (ventricular response), corrected QT interval according to Bazzett's formula, presence of QRS complex abnormalities and ST-T changes were analyzed. Data analysis were performed using SPSS 20.0 for Windows.

RESULT

A total of 19.718 ECG data were obtained, taken from the Makassar Telemedicine study data center at Hasanuddin University Hospital which cover all Public Health Center and a private clinic in Makassar city. From this population, AF was found in 189 (0.96%) ECGs. 98 (51.9%) are males' and 91 (48.1%) of which are females'. AF is increasingly prevalent with increasing ages. There was a significant difference on the QRS axis between male and female with a p value of <0.001. The duration of the QRS complex between men and women was significantly different (p=0.038). QTc value was also found to be significantly different between male and female (p=0.001). AF was accompanied by PVC in 9 males and 2 females.

CONCLUSION

The prevalence of AF in the Makassar population is 0.96%, more common in men and elderly.

Racial and Ethnic Differences in the Management of Atrial Fibrillation

Atrial fibrillation (AF) is the most common clinical arrhythmia, and it results in adverse outcomes and increased healthcare costs. Racial and ethnic differences in AF management, although recognized, are poorly understood. This review summarizes racial differences in AF epidemiology, genetics, clinical presentation, and management. In addition, it highlights the underrepresentation of racial and ethnic populations in AF clinical trials, especially trials focused on stroke prevention. Specific strategies are proposed for future research and initiatives that have potential to eliminate racial and ethnic differences in the care of patients with AF. Addressing racial and ethnic disparities in healthcare access, enrollment in clinical trials, resource allocation, prevention, and management will likely narrow the gaps in the care and outcomes of racial and ethnic minorities suffering from AF.

Coordinating Healthcare with Artificial intelligence-supported Technology for Atrial Fibrillation patients (CHAT-AF): Protocol for a Randomised Controlled Trial (Preprint)

Background

Atrial fibrillation (AF) is an increasingly common chronic health condition for which integrated care that is multidisciplinary and patient-centric is recommended yet challenging to implement.

Objective

The aim of Coordinating Health Care With Artificial Intelligence–Supported Technology in AF is to evaluate the feasibility and potential efficacy of a digital intervention (AF-Support) comprising preprogrammed automated telephone calls (artificial intelligence conversational technology), SMS text messages, and emails, as well as an educational website, to support patients with AF in self-managing their condition and coordinate primary and secondary care follow-up.

Methods

Coordinating Health Care With Artificial Intelligence–Supported Technology in AF is a 6-month randomized controlled trial of adult patients with AF (n=385), who will be allocated in a ratio of 4:1 to AF-Support or usual care, with postintervention semistructured interviews. The primary outcome is AF-related quality of life, and the secondary outcomes include cardiovascular risk factors, outcomes, and health care use. The 4:1 allocation design enables a detailed examination of the feasibility, uptake, and process of the implementation of AF-Support. Participants with new or ongoing AF will be recruited from hospitals and specialist-led clinics in Sydney, New South Wales, Australia. AF-Support has been co-designed with clinicians, researchers, information technologists, and patients. Automated telephone calls will occur 7 times, with the first call triggered to commence 24 to 48 hours after enrollment. Calls follow a standard flow but are customized to vary depending on patients’ responses. Calls assess AF symptoms, and participants’ responses will trigger different system responses based on prespecified protocols, including the identification of red flags requiring escalation. Randomization will be performed electronically, and allocation concealment will be ensured. Because of the nature of this trial, only outcome assessors and data analysts will be blinded. For the primary outcome, groups will be compared using an analysis of covariance adjusted for corresponding baseline values. Randomized trial data analysis will be performed according to the intention-to-treat principle, and qualitative data will be thematically analyzed.

Results

Ethics approval was granted by the Western Sydney Local Health District Human Ethics Research Committee, and recruitment started in December 2020. As of December 2021, a total of 103 patients had been recruited.

Conclusions

This study will address the gap in knowledge with respect to the role of postdischarge digital care models for supporting patients with AF.

Trial Registration

Australian New Zealand Clinical Trials Registry ACTRN12621000174886; https://www.australianclinicaltrials.gov.au/anzctr/trial/ACTRN12621000174886

International Registered Report Identifier (IRRID)

DERR1-10.2196/34470

A retrospective analysis of the investigative practices of acute limb ischaemia presenting with an unknown aetiology

BACKGROUND

Acute limb ischaemia (ALI) is a limb and life-threatening condition with significant morbidity. There are currently no consensus recommendations for the investigative practices to determine the aetiology of ALI presenting without a known aetiology. We undertook a detailed analysis of all investigations performed to identify an underlying precipitant in those with unexplained ALI and formulated a suggested diagnostic algorithm for the evaluation of unexplained ALI.

METHODS

ALI cases presenting to a tertiary referral centre over a 3-year period were reviewed, and known aetiologies, and investigations undertaken to determine the underlying aetiology of unexplained ALI were obtained.

RESULTS

Unexplained ALI was found in 27 of 222 patients (12%), of which 21 (78%) had a cause for ALI established after further investigations. Six patients had no cause identified despite extensive work-up. Most patients with unexplained ALI had a cardioembolic source identified as the underlying cause (62%), and this included atrial fibrillation, infective endocarditis, cardiac myxoma and intra-cardiac thrombus. Other causes of unexplained ALI were detected by computed tomography (CT) imaging and included newly diagnosed significant atherosclerotic disease (19%), embolism from isolated proximal large vessel thrombus (10%) and metastatic malignancy (10%). There were no cases attributed to inherited thrombophilias, myeloproliferative neoplasms or anti-phospholipid syndrome.

CONCLUSION

Among patients with unexplained ALI, the majority had a cardioembolic source highlighting the importance of comprehensive cardiac investigations. A subset of patients had alternative causes identified on CT imaging. These data support the use of a collaborative and integrative diagnostic algorithm in the evaluation of unexplained ALI.

Atrial Fibrillation Is Associated with Cognitive Impairment, All-Cause Dementia, Vascular Dementia, and Alzheimer's Disease: a Systematic Review and Meta-Analysis

BACKGROUND

Atrial fibrillation (AF) is a risk factor for cognitive impairment and dementia in patients with stroke history. However, the association between AF and cognitive impairment in broader populations is less clear.

OBJECTIVE

To systematically review and quantitatively synthesize the existing evidence regarding the association of AF with cognitive impairment of any severity and etiology and dementia.

METHODS

Medline, Scopus, and Cochrane Central were searched in order to identify studies investigating the association between AF and cognitive impairment (or dementia) cross-sectionally and longitudinally. Studies encompassing and analyzing exclusively patients with stroke history were excluded. A random-effects model meta-analysis was conducted. Potential sources of between-study heterogeneity were investigated via subgroup and meta-regression analyses. Sensitivity analyses including only studies reporting data on stroke-free patients, vascular dementia, and Alzheimer's disease were performed.

RESULTS

In total, 43 studies were included. In the pooled analysis, AF was significantly associated with dementia (adjusted OR, 1.6; 95% CI, 1.3 to 2.1; I², 31%) and the combined endpoint of cognitive impairment or dementia (pooled adjusted OR, 1.5; 95% CI, 1.4 to 1.8; I², 34%). The results were significant, even when studies including only stroke-free patients were pooled together (unadjusted OR, 2.2; 95% CI, 1.4 to 3.5; I², 96%), but the heterogeneity rates were high. AF was significantly associated with increased risk of both vascular (adjusted OR, 1.7; 95% CI, 1.2 to 2.3; I², 43%) and Alzheimer's dementia (adjusted HR, 1.4; 95% CI, 1.2 to 1.6; I², 42%).

CONCLUSION

AF increases the risk of cognitive impairment, all-cause dementia, vascular dementia, and Alzheimer's disease. Future studies should employ interventions that may delay or even prevent cognitive decline in AF patients.

Rationale and design of the IRON-AF study: a double-blind, randomised, placebo-controlled study to assess the effect of intravenous ferric carboxymaltose in patients with atrial fibrillation and iron deficiency

INTRODUCTION

Atrial fibrillation (AF) is associated with significantly impaired quality-of-life. Iron deficiency (ID) is prevalent in patients with AF. Correction of ID in other patient populations with intravenous iron supplementation has been shown to be a safe, convenient and effective way of improving exercise tolerance, fatigue and quality-of-life. The IRON-AF (Effect of Iron Repletion in Atrial Fibrillation) study is designed to assess the effect of iron repletion with intravenous ferric carboxymaltose in patients with AF and ID.

METHODS AND ANALYSIS

The IRON-AF study is a double-blind, randomised controlled trial that will recruit at least 84 patients with AF and ID. Patients will be randomised to receive infusions of either ferric carboxymaltose or placebo, given in repletion and then maintenance doses. The study will have follow-up visits at weeks 4, 8 and 12. The primary endpoint is change in peak oxygen uptake from baseline to week 12, as measured by cardiopulmonary exercise testing (CPET) on a cycle ergometer. Secondary endpoints include changes in quality-of-life and AF disease burden scores, blood parameters, other CPET parameters, transthoracic echocardiogram parameters, 6-minute walk test distance, 7-day Holter/Event monitor burden of AF, health resource utilisation and mortality.

ETHICS AND DISSEMINATION

The study protocol has been approved by the Central Adelaide Local Health Network Human Research Ethics Committee, Australia. The results of this study will be disseminated through publications in peer-reviewed journals and conference presentations.

TRIAL REGISTRATION NUMBER

Australian New Zealand Clinical Trials Registry (ACTRN12620000285954).

The change of renal functions after nonvitamin K oral anticoagulants in patients with atrial fibrillation

Oral anticoagulants decreased stroke and mortality in atrial fibrillation patients. There have been cumulative data suggesting that some oral anticoagulants may exert favorable renal outcomes.The aim of this study is to evaluate the renal outcomes in patients with atrial fibrillation who took oral anticoagulant.

METHODS

A Retrospective cohort study using hospital electronic database. Serum creatinine and GFR were collected at baseline and at 1 and 2 years.

RESULTS

Authors identified 734 patients with non-valvular AF who took oral anticoagulants. At the end of 2-year, the cumulative risk of significant GFR decline (eGFR drop > 30%) was 10.94% in warfarin group and 9.69% in NOACs group.The incidence rate of significant eGFR decline were comparable between NOACs and warfarin group which were 4.82 and 5.34 per 100-patient year respectively(HR 1.01 CI 0.62-1.66 , p- value 0.964).However, the adjusted mean eGFR change per year was significantly lower in NOAC group, especially rivaroxaban (coefficient 7.83 ,CI 4.44 11.22 , p-value < 0.001) and dabigatran (coefficient 6.22 ,CI 2.67-9.77 , p-value = 0.001) at 2 years.

CONCLUSIONS

Significant GFR decline was not uncommon in non-valvular AF patients who received anticoagulant. Among these, the proportion of patients who had significant eGFR decline(>30%) were comparable between NOACs and warfarin at 2 years. However, there is a significantly less mean eGFR decline per year in patients who receive NOACs, notably with dabigatran and rivaroxaban, than those who receive warfarin.The findings of this study should be interpreted in the context of patients included in this study.

Direct Oral Anticoagulants in Asian Patients with Atrial Fibrillation: Consensus Recommendations by the Asian Pacific Society of Cardiology on Strategies for Thrombotic and Bleeding Risk Management

The disease burden of AF is greater in Asia-Pacific than other areas of the world. Direct oral anticoagulants (DOACs) have emerged as effective alternatives to vitamin K antagonists (VKA) for preventing thromboembolic events in patients with AF. The Asian Pacific Society of Cardiology developed this consensus statement to guide physicians in the management of AF in Asian populations. Statements were developed by an expert consensus panel who reviewed the available data from patients in Asia-Pacific. Consensus statements were developed then put to an online vote. The resulting 17 statements provide guidance on the assessment of stroke risk of AF patients in the region, the appropriate use of DOACs in these patients, as well as the concomitant use of DOACs and antiplatelets, and the transition to DOACs from VKAs and vice versa. The periprocedural management of patients on DOAC therapy and the management of patients with bleeding while on DOACs are also discussed.

Coronary artery thromboembolism from left appendage mural thrombus- a rare complication from atrial fibrillation

A 54-year-old man with recurrent, persistent atrial fibrillation was found dead unexpectedly. He was reportedly non-compliant with his medications and was not on anti-coagulant therapy. He was found dead in his residence after complaining of abdominal discomfort a day prior to death. Postmortem examination revealed a thromboembolus occluding the left anterior descending coronary artery that originated from a mural thrombus in the left appendage, in addition to kidney infarcts. Although atrial fibrillation-related thromboembolism is often speculated to be a cause of myocardial infarction with non-obstructive coronary arteries, supporting pathological evidence is rare. This case documents radiological, macroscopic and microscopic images of this important complication from atrial fibrillation.

Left atrial, pulmonary vein, and left atrial appendage anatomy in Indigenous individuals: Implications for atrial fibrillation

Background

Indigenous Australians experience a greater burden of AF. Whether this is in-part due to differences in arrhythmogenic structures that appear to contribute to AF differences amongst other ethnicities is not known.

Methods

We studied forty individuals matched for ethnicity and other AF risk factors. Computed tomography imaging was used to characterise left atrial (LA), pulmonary vein (PV), and left atrial appendage (LAA) anatomy.

Results

There were no significant differences in LA diameters or volumes between Indigenous and non-Indigenous Australians. Similarly, we could not detect any consistent differences in PV number, morphology, diameters, or ostial characteristics according to ethnicity. LAA analyses suggested that Indigenous Australians may have a greater proportion of non chickenwing LAA type, and a tendency for eccentric, oval-shaped LAA ostia; however, there were no other differences seen with regards to LAA volume or depth. Indexed values for LA, PV and LAA anatomy corrected for body size were broadly similar.

Conclusions

In a cohort of individuals matched for AF risk factors, we could find no strong evidence of ethnic differences in LA, PV, and LAA characteristics that may explain a predisposition of Indigenous Australians for atrial arrhythmogenesis. These findings, in conjunction with our previous data showing highly prevalent cardiometabolic risk factors in Indigenous Australians with AF, suggest that it is these conditions that are more likely responsible for the AF substrate in these individuals. Continued efforts should therefore be directed towards risk factor management in an attempt to prevent and minimise the effects of AF in Indigenous Australians.

Atrial Fibrillation in Remote Indigenous and Non-Indigenous Individuals Hospitalised in Central Australia

BACKGROUND

The epidemiology of atrial fibrillation (AF) amongst Indigenous populations remains poorly characterised. We studied hospitalisations for AF in Central Australia, the most populous Indigenous region in the country.

METHODS

Patients with a diagnosis of AF admitted to Alice Springs Hospital, the only secondary health care facility and provider of cardiac care in remote Central Australia, were identified from 2006 to 2016. Age and gender-specific hospitalised AF prevalence, comorbidities, and CHA₂DS₂-VASc scores were ascertained.

RESULTS

Of 57,056 admitted patients over the study period, 1,210 (2.1%; 46% Indigenous) had a diagnosis of AF. For Indigenous and non-Indigenous individuals <45 years, hospitalised AF prevalence per 10,000 population was 105 (CI 84-131) and 50 (CI 36-68) in males (ratio=2.10), and 98 (CI 77-123) and 12 (CI 6-23) in females (ratio=7.92), respectively. For Indigenous and non-Indigenous individuals ≥65 years, hospitalised AF prevalence per 10,000 was 1,577 (CI 1,194-2,026) and 2,326 (CI 2,047-2,623) in males (ratio=0.68), and 1,713 (CI 1,395-2,069) and 1,897 (1,623-2,195) in females (ratio=0.90). Indigenous individuals had higher rates of cardiometabolic comorbidities, particularly at younger ages. CHA₂DS₂-VASc scores were greater in Indigenous individuals, particularly those <45 years (2.5±1.5 versus 0.7±1.1, p<0.001).

CONCLUSIONS

The prevalence of hospitalised AF amongst Indigenous people in remote Central Australia was significantly higher than in non-Indigenous individuals, particularly in younger age groups and females. Indigenous individuals with hospitalised AF also had a markedly greater prevalence of cardiometabolic comorbidities and elevated stroke risk. These data suggest that AF may be contributing to the gap in morbidity and mortality experienced by Indigenous Australians.

Hypertension, Prehypertension, Hypertensive Heart Disease, and Atrial Fibrillation

Hypertension (HT) confers the highest population-attributable risk among factors leading to atrial fibrillation (AF). Data also are accumulating regarding the association between pre-HT, aortic stiffness, and increased incident AF or AF recurrence. Atrial remodeling due to HT is progressive but also reversible. Although inhibition of the renin-angiotensin-aldosterone system has shown the greatest promise in improving AF outcomes, optimal blood pressure targets in individuals with HT and AF remain elusive. AF management demands an integrated care approach. HT is best treated alongside a comprehensive risk factor management program where other AF risk factors are targeted, with involvement of a multidisciplinary team.

Final-year nursing students' foundational knowledge and self-assessed confidence in interpreting cardiac arrhythmias: A cross-sectional study

BACKGROUND

Graduating nurses should possess knowledge and understanding of cardiac arrhythmia interpretation, so they can assess abnormal and life-threatening arrhythmias. However, literature around nursing students' foundational knowledge in cardiac arrhythmia interpretation remains scarce.

OBJECTIVES

To examine final-year nursing students' foundational knowledge and self-assessed confidence in interpreting cardiac arrhythmias.

DESIGN

Cross-sectional study design.

SETTINGS

Two Australian universities (one regional and the other large metropolitan).

PARTICIPANTS

Nursing students in the final year of a program of study leading to initial registration as a registered nurse.

METHODS

An online survey was adopted to examine final-year nursing students' foundational knowledge and their self-assessed confidence when interpreting cardiac rhythms.

RESULTS

A total of 114 participants completed surveys, representing a response rate of 22%. More than 70% of the participants were able to interpret asystole, sinus rhythm, and sinus bradycardia. Over 50% correctly identified ventricular tachycardia, atrial flutter, sinus tachycardia, atrial fibrillation, and ventricular fibrillation. Under 15% of the participants were able to interpret junctional rhythm, paced rhythm, and unifocal/multifocal premature ventricular contractions. Self-assessed confidence levels were generally lower than the accuracy rates of arrhythmia interpretation. Although many participants acknowledged that learning arrhythmia interpretation was difficult and challenging, most of them had positive perceptions and wanted to learn more.

CONCLUSION

Nursing curricula need to be supported and strategies need to be implemented to standardise educational electrocardiogram interpretation programs, which are critical to improving final-year nursing students' foundational knowledge and confidence in interpreting cardiac arrhythmias and enhancing patient safety.

Postoperative Atrial Fibrillation and Long-Term Risk of Stroke in Patients Undergoing Liver Transplantation

BACKGROUND AND PURPOSE

Postoperative atrial fibrillation (POAF) is the commonest cardiovascular complication following liver transplantation (LT). This study sought to assess a possible association of POAF with subsequent thromboembolic events in patients undergoing LT.

METHODS

A retrospective cohort study of consecutive adults undergoing LT between 2010 and 2018 was undertaken. Patients were classified as POAF if atrial fibrillation (AF) was documented within 30 days of LT without a prior history of AF. Cases of ischemic stroke or systemic embolism were adjudicated by a panel of 2 independent physicians.

RESULTS

Among the 461 patients included, POAF occurred in 47 (10.2%) a median of 3 days following transplantation. Independent predictors of POAF included advancing age, postoperative sepsis and left atrial enlargement. Over a median follow-up of 4.9 (interquartile range, 2.9-7.2) years, 21 cases of stroke and systemic embolism occurred. Rates of thromboembolic events were significantly higher in patients with POAF (17.0% versus 3.1%; P<0.001). After adjustment, POAF remained a strong independent predictor of thromboembolic events (hazard ratio, 8.36 [95% CI, 2.34-29.79]). Increasing CHA₂DS₂VASc score was also an independent predictor of thromboembolic events (hazard ratio, 1.58 [95% CI, 1.02-2.46]). A model using POAF and a CHA₂DS₂VASc score ≥2 alone yielded a C statistic of 0.77, with appropriate calibration for the prediction of thromboembolic events. However, POAF was not an independent predictor of long-term mortality.

CONCLUSIONS

POAF following LT is associated with an 8-fold increased risk of thromboembolic events and the use of the CHA₂DS₂VASc score may facilitate risk stratification of these patients. Prospective studies are warranted to assess whether the use of oral anticoagulants can reduce the risk of thromboembolism following LT.

Increased serum interleukin-6 level as a predictive biomarker for atrial fibrillation: A systematic review and meta-analysis

BACKGROUND

Atrial fibrillation (AF) is related to a higher risk of thromboembolic events and mortality. Some studies have demonstrated that the inflammatory biomarker interleukin-6 (IL-6) is associated with a higher risk of higher thrombosis in AF patients, but the real effect of IL-6 remains a controversy.

METHODS

We conducted a systematic review and meta-analysis to investigate the association between IL-6 and thromboembolic events, as well as bleeding events, acute coronary syndrome (ACS) events and all-cause mortality in AF.

RESULTS

A total of five studies involving 22 928 patients met our inclusion criteria for the systematic review. The higher level of IL-6 in AF patients is related to long-term thromboembolic events including stroke (RR 1.44, CI 95% 1.09-1.90, p=0.01). IL-6 meant a higher risk of long-term bleeding risk (RR 1.36, CI 95% 1.06-1.74, p=0.02), ACS risk (RR 1.81, CI 95% 1.43-2.30, p<0.001) and all-cause mortality (RR 2.35, CI 95% 2.09-2.65, p<0.001).

CONCLUSION

A higher level of IL-6 may predict a greater number of long-term thromboembolic events and bleeding events, ACS events and mortality in AF patients. Further studies such as the cut-off point of IL-6 need to be conducted in the future.

Predictors of Anticoagulation Use in Indigenous and Non-Indigenous Australians With Atrial Fibrillation

OBJECTIVE

Prior studies have demonstrated that anticoagulation underutilisation for atrial fibrillation (AF) and elevated stroke risk is common. However, there is little data on factors associated with appropriate anticoagulation, particularly in Indigenous Australians who face a disproportionate burden of AF and stroke. We thus sought to determine factors associated with anticoagulation use in Australians with AF.

DESIGN

Administrative, clinical, prescriptive and laboratory data were linked and aggregated over a 12-year period.

SETTING

Single tertiary teaching hospital.

PARTICIPANTS

19,305 (98%) and 308 (2%) consecutive non-Indigenous and Indigenous Australians with AF identified from administrative databases.

MAIN OUTCOME MEASURES

Associations of anticoagulation use according to ethnicity.

RESULTS

Significant independent predictors of anticoagulation use included hypertension (odds ratio [OR] 1.25, 95% confidence interval [CI] 1.17-1.34; p<0.001), diabetes (OR 1.14, 95% CI 1.05-1.24; p=0.002), heart failure (OR 1.54 95% CI 1.43-1.66; p<0.001) and prior stroke or transient ischaemic attack (OR 2.07, 95% CI 1.84-2.33; p<0.001). In contrast, increasing age (OR 0.99, 95% CI 0.98-0.99; p<0.001), female gender (OR 0.88, 95% CI 0.82-0.93; p<0.001), and vascular disease (OR 0.72, 95% CI 0.64-0.80; p<0.001) were significant predictors of no anticoagulation. Hypertension was associated with less anticoagulation use in Indigenous compared to non-Indigenous Australians (p=0.02).

CONCLUSIONS

Anticoagulation for AF was suboptimal in both Indigenous and non-Indigenous Australians. Older age, female gender, and comorbid vascular disease were found to be negatively associated with anticoagulation. Importantly, hypertension may also be under-recognised as a stroke risk factor in Indigenous Australians. Future efforts to encourage anticoagulation use in accordance with guideline recommendations is likely to reduce the burden of AF-related stroke in both Indigenous and non-Indigenous populations.

Oral anticoagulation and cardiovascular outcomes in patients with atrial fibrillation and chronic kidney disease in Asian Population, Data from the COOL-AF Thailand registry

BACKGROUND AND OBJECTIVES

Patients with AF and chronic kidney disease(CKD) encountered increased risks of stroke, bleeding, morbidity, and overall mortality. Oral anticoagulation in these populations definitely enhances major bleeding but the benefit of stroke reduction remained inconclusive.The aim of this study is to evaluate the effect of oral anticoagulation (OAC) on the 2-year cardiovascular outcomes in patients with AF and CKD.

METHOD

NVAF patients were consecutively enrolled from 27 hospitals located all across Thailand.Baseline demographic and clinical data were collected within 6 months from enrollment.GFR was calculated using CKD-EPI formula. CKD patients were defined as GFR less than 60 mL/min/1.73 m² according to KDOQI of the National Kidney Foundation. Clinical outcomes included ischemic stroke or transient ischemic attack (TIA) and major bleeding.

RESULTS

At 25.7 ± 10.6 months of follow up, we identified 2538 patients with complete renal follow-up data. Among these were 1594 patients with CKD (stage 3-5) and 944 patients without CKD. The rate of ischemic stroke in patients with and without CKD were 3.7% and 1.7% respectively (p = 0.004),the rate of major bleeding was 5.6 and 3.5% accordingly (p = 0.015) and, likewise, the death rate was substantially high in patients with CKD (10.0% and 6.5%, p = 0.02). The rate of ischemic stroke/TIA in patients with CKD who were and were not on OAC did not differ significantly, 3.6% and 4.2% respectively (p = 0.602). NOAC and warfarin did not differ significantly in the propensity score-matched rate of both ischemic stroke/TIA (0 and 1.2%, p = 0.554) and major bleeding (3.3% and 7.4%, p = 0.122).The net clinical benefit of NOAC over warfarin was 2.153 per 100-patient years.

CONCLUSIONS

COOL AF registry demonstrated that AF patients with CKD had increased risks of ischemic stroke/TIA, major bleeding and death. The benefit of stroke/TIA reduction was not significantly evident for either warfarin or NOAC. However, NOAC was associated with the positive net clinical benefit over no OAC.

Global variations in the prevalence, treatment, and impact of atrial fibrillation in a multi-national cohort of 153 152 middle-aged individuals

AIMS

To compare the prevalence of electrocardiogram (ECG)-documented atrial fibrillation (or flutter) (AF) across eight regions of the world, and to examine antithrombotic use and clinical outcomes.

METHODS AND RESULTS

Baseline ECGs were collected in 153 152 middle-aged participants (ages 35-70 years) to document AF in two community-based studies, spanning 20 countries. Medication use and clinical outcome data (mean follow-up of 7.4 years) were available in one cohort. Cross-sectional analyses were performed to document the prevalence of AF and medication use, and associations between AF and clinical events were examined prospectively. Mean age of participants was 52.1 years, and 57.7% were female. Age and sex-standardized prevalence of AF varied 12-fold between regions; with the highest in North America, Europe, China, and Southeast Asia (270-360 cases per 100 000 persons); and lowest in the Middle East, Africa, and South Asia (30-60 cases per 100 000 persons) (P < 0.001). Compared with low-income countries (LICs), AF prevalence was 7-fold higher in middle-income countries (MICs) and 11-fold higher in high-income countries (HICs) (P < 0.001). Differences in AF prevalence remained significant after adjusting for traditional AF risk factors. In LICs/MICs, 24% of participants with AF and a CHADS2 score ≥1 received antithrombotic therapy, compared with 85% in HICs. AF was associated with an increased risk of stroke [hazard ratio (HR) 2.29; 95% confidence interval (CI) 1.49-3.52] and death (HR 2.97; 95% CI 2.25-3.93); with similar rates in different countries grouped by income level.

CONCLUSIONS

Large variations in AF prevalence occur in different regions and countries grouped by income level, but this is only partially explained by traditional AF risk factors. Antithrombotic therapy is infrequently used in poorer countries despite the high risk of stroke associated with AF.