Asymptomatic vs. symptomatic atrial fibrillation: Clinical outcomes in heart failure patients

The 2024 ESC guidelines on atrial fibrillation: essential updates for everyday clinical practice

Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia, and it is associated with substantial morbidity, mortality, and economic burden. Effective management of AF remains a critical focus in contemporary medicine, given its complex and multifaceted nature. In the present paper, we provide the essential updates for everyday clinical practice from the 2024 European Society of Cardiology (ESC) guidelines for AF management. We highlight seven key areas encompassing the adoption of the CHA₂DS₂-VA score for thromboembolic risk stratification, changes in bleeding risk assessment, expanded indications for catheter ablation, promotion of the multidisciplinary AF-CARE pathway for patient management, new recommendations for left atrial appendage closure, updates on clinical decision-making for atrial high-rate episodes, and considerations on the future role of artificial intelligence in advancing predictive analytics. We also compare the new recommendations proposed by the ESC 2024 AF guidelines with the ESC 2021 edition and the 2023 guidelines published by the American College of Cardiology/American Heart Association (ACC/AHA), reflecting regional perspectives and advancements in the field. By presenting these practical updates and their implications for routine practice, this paper aims to guide clinicians in adopting the latest evidence-based approaches to optimize AF patients' care.

Continuing evaluation of atrial fibrillation detection after cryptogenic stroke: 2-year findings from a multicentre study with Confirm Rx ICM

BACKGROUND

The detection of atrial fibrillation (AF) after a cryptogenic stroke (CS) carries important therapeutic implications. In this study, we aimed to accurately assess the incidence of AF among CS subjects by using an insertable cardiac monitor (ICM).

METHODS

A prospective, single-arm, multicentre registry was conducted to identify AF in 155 CS subjects using the Confirm Rx ICM (Abbott, California, USA) across 20 global sites. Inclusion criteria comprised participants aged 40 years or older who had experienced CS within a 90-day window. At each follow-up visit, expert electrophysiologists reviewed and adjudicated ICM detected AF episodes. The primary endpoint was the cumulative incidence of true device-detected AF (lasting more than 30 s) at 6 months, evaluated with Kaplan-Meier methods.

RESULTS

AF incidence was 21.3% (95% CI 15.3% to 29.1%) at 6 months, increasing to 48.8% (95% CI 34.7% to 64.9%) at 24 months. Subjects with AF detection experienced an average of 50.9 true AF episodes per subject per year. The median time from implantation to AF detection (>30 s) was 72 days (IQR 7-261). Among subjects with 30 s AF detection, anticoagulation therapy was initiated in 65.2% (30/46) of subjects. Oral anticoagulation medication was prescribed in 8.3% (9/109) of subjects without AF. Recurrent ischaemic stroke or transient ischaemic attack occurred in 5 subjects (3.2%, 5/155).

CONCLUSION

These results show that ICM-driven long-term continuous AF monitoring is associated with high diagnostic yield in CS subjects.

TRIAL REGISTRATION NUMBER

NCT03505801.

Economic Evaluations in Electrophysiology in the Last 15 Years: A Systematic Review of the Literature

Background

Electrophysiology (EP) procedures, including cardiac implantable electronic devices (CIEDs) and ablations, are widely used to manage arrhythmias and heart failure. These interventions, though effective, require substantial resources, prompting the need for systematic economic evaluations to inform healthcare decision-making.

Methods

A systematic review of studies from 2007 to 2024 was conducted in two phases. Phase one assessed trends in economic evaluations of EP procedures, analyzing 129 studies across regions and timeframes. Phase two focused on cost-effectiveness analyses of implantable cardioverter defibrillators (ICDs), cardiac resynchronization therapy defibrillators (CRT-Ds), and atrial fibrillation (AF) ablation, examining outcomes like quality-adjusted life years (QALYs) and incremental cost-effectiveness ratios (ICERs), while identifying factors influencing economic results.

Results

EP procedures generally demonstrated favorable cost-effectiveness, particularly in high-income regions. Studies on ICDs and CRT-Ds consistently supported their economic value for patients with arrhythmias or heart failure, while AF ablation showed potential for long-term benefits, particularly when compared to medical therapies. However, results varied by region, reflecting differences in healthcare systems, costs, and patient populations.

Conclusions

The review highlights the overall cost-effectiveness of EP procedures in many settings but underscores the need for tailored economic evaluations in low- and middle-income countries. Simplified methodologies and greater attention to regional contexts are recommended to guide resource allocation and policy development globally.

Major clinical outcomes in symptomatic vs. asymptomatic atrial fibrillation: a meta-analysis

BACKGROUND AND AIMS

Current guidelines suggest that asymptomatic atrial fibrillation (AF) is independently associated with increased risks of stroke and mortality compared with symptomatic AF. Considering that recent investigations have provided conflicting results, the present study aimed to evaluate the association between symptom status and clinical outcomes in patients with AF.

METHODS

Medline, Cochrane Library, and Scopus were searched until 25 March 2024. Triple-independent study selection, data extraction and quality assessment were performed. Evidence was pooled using random-effects meta-analyses.

RESULTS

Thirty-six studies (217 850 participants) were included. Based on the frequentist analysis, symptomatic individuals had no significant difference in the risk of all-cause mortality [hazard ratio (HR) .97, 95% confidence interval (CI) .80-1.17], cardiovascular mortality (HR 1.04, 95% CI .72-1.49), thromboembolism (HR 1.06, 95% CI .87-1.28), stroke (HR 1.06, 95% CI .84-1.34), hospitalization (HR 1.34, 95% CI .89-2.02), and myocardial infarction (HR .98, 95% CI .70-1.36), compared to the asymptomatic group. Symptomatic patients had a 33% increased risk of new-onset heart failure (HR 1.33, 95% CI 1.19-1.49) and a 30% lower risk of progression to permanent AF (HR .70, 95% CI .54-.89). The Bayesian analysis yielded comparable results, yet the association between symptom status and new-onset heart failure was not significant (HR 1.27, 95% credible interval .76-1.93; Bayes factor = 1.2). Symptomatic patients had higher odds of receiving antiarrhythmic drugs (odds ratio [OR] 1.64, 95% CI 1.33-2.03) and ablation therapy (OR 1.47, 95% CI 1.06-2.05) compared to asymptomatic cases.

CONCLUSIONS

The risk of major clinical outcomes did not differ between individuals with and without AF-related symptoms. Asymptomatic patients had a greater hazard of progression to permanent AF.

Atrial fibrillation burden in clinical practice, research, and technology development: a clinical consensus statement of the European Society of Cardiology Council on Stroke and the European Heart Rhythm Association

Atrial fibrillation (AF) is one of the most common cardiac diseases and a complicating comorbidity for multiple associated diseases. Many clinical decisions regarding AF are currently based on the binary recognition of AF being present or absent with the categorical appraisal of AF as continued or intermittent. Assessment of AF in clinical trials is largely limited to the time to (first) detection of an AF episode. Substantial evidence shows, however, that the quantitative characteristic of intermittent AF has a relevant impact on symptoms, onset, and progression of AF and AF-related outcomes, including mortality. Atrial fibrillation burden is increasingly recognized as a suitable quantitative measure of intermittent AF that provides an estimate of risk attributable to AF, the efficacy of antiarrhythmic treatment, and the need for oral anticoagulation. However, the diversity of assessment methods and the lack of a consistent definition of AF burden prevent a wider clinical applicability and validation of actionable thresholds of AF burden. To facilitate progress in this field, the AF burden Consensus Group, an international and multidisciplinary collaboration, proposes a unified definition of AF burden. Based on current evidence and using a modified Delphi technique, consensus statements were attained on the four main areas describing AF burden: Defining the characteristics of AF burden, the recording principles, the clinical relevance in major clinical conditions, and implementation as an outcome in the clinic and in clinical trials. According to this consensus, AF burden is defined as the proportion of time spent in AF expressed as a percentage of the recording time, undertaken during a specified monitoring duration. A pivotal requirement for validity and comparability of AF burden assessment is a continuous or near-continuous duration of monitoring that needs to be reported together with the AF burden assessment. This proposed unified definition of AF burden applies independent of comorbidities and outcomes. However, the disease-specific actionable thresholds of AF burden need to be defined according to the targeted clinical outcomes in specific populations. The duration of the longest episode of uninterrupted AF expressed as a time duration should also be reported when appropriate. A unified definition of AF burden will allow for comparability of clinical study data to expand evidence and to establish actionable thresholds of AF burden in various clinical conditions. This proposed definition of AF burden will support risk evaluation and clinical treatment decisions in AF-related disease. It will further promote the development of clinical trials studying the clinical relevance of intermittent AF. A unified approach on AF burden will finally inform the technology development of heart rhythm monitoring towards validated technology to meet clinical needs.

Subclinical atrial fibrillation/atrial high-rate episodes: what significance and decision-making?

Subclinical atrial fibrillation (AF) and atrial high-rate episodes (AHREs) are often detected incidentally through cardiac implantable electronic devices or wearables, especially in asymptomatic patients. These episodes pose a clinical challenge as they are associated with an increased risk of stroke, albeit at a lower rate compared with clinical AF. This review discusses the evolving understanding of AHRE, highlighting the uncertainties regarding optimal management, particularly the use of oral anticoagulants. Two key trials, ARTESiA and NOAH-AFNET 6, investigated anticoagulation in patients with device-detected AHRE. ARTESiA found that apixaban significantly reduced stroke or systemic embolism, but with an increased risk of major bleeding. In contrast, NOAH-AFNET 6, which tested edoxaban, did not demonstrate a significant benefit in reducing cardiovascular events but also observed higher bleeding rates. A meta-analysis of these trials confirmed the efficacy of oral anticoagulants in lowering ischaemic stroke risk, though with an elevated bleeding risk. Given these findings, clinical decision-making in patients with AHRE must be individualized, taking into account stroke risk, bleeding risk, and patient preferences. Shared decision-making is crucial to balance the benefits and risks of anticoagulation, especially in the context of progression to clinical AF and its associated stroke risk. Moreover, it is essential to educate patients about the risk of bleeding complications and emphasize the importance of close monitoring. Future research may further clarify optimal anticoagulation strategies and better define high-risk subgroups that would most benefit from therapy.

Relationship between predictive factors and atrial high-rate episodes in heart failure with reduced ejection fraction patients with cardiac implantable electronic devices

OBJECTIVE

Atrial high-rate episodes (AHRE) are atrial tachyarrhythmia episodes detected by implanted cardiac devices, characterised by an atrial rate exceeding 180-190 beats per minute. Recent studies have linked AHRE to the development of atrial fibrillation (AF) and increased stroke risk, especially when episodes last longer than 5-6 min. This study aimed to evaluate the relationship between predictive factors and the occurrence of AHRE in heart failure with reduced ejection fraction (HFrEF) patients with cardiac implantable electronic devices (CIEDs).

METHODS

This single-centre, retrospective study included a cohort of 155 consecutive HFrEF patients with CIEDs, but without a diagnosis of AF, enrolled between January 2023 and December 2023. Patients were stratified based on the presence of AHRE detected during device interrogation.

RESULTS

The average age of the patients was 54 ± 14 years, and 83.2% of the study population were male. Patients with AHRE had a reduced left ventricular ejection fraction (LVEF) (p = 0.026) and an increased left atrial diameter (p < 0.001) compared to the group without AHRE. Patients with AHRE had elevated levels of creatinine, uric acid, and TSH compared to those without AHRE (p = 0.006, p = 0.021, p = 0.009, respectively). In the univariable logistic regression analysis, LVEF (HR = 0.690, 95% CI = 0.610-0.913, p = 0.013), left atrial diameter (HR = 8.215, 95% CI = 1.557-43.34, p < 0.001), creatinine (HR = 7.369, 95% CI = 1.749-31.05, p = 0.006), uric acid (HR = 1.073, 95% CI = 1.062-1.196, p = 0.020), total cholesterol (HR = 0.989, 95% CI = 0.979-0.999, p = 0.031), and C-reactive protein levels (HR = 1.146, 95% CI = 1.002-1.131, p = 0.047) were identified as independent predictors of AHRE. In multivariable logistic regression analysis, left ventricular ejection fraction (HR = 0.890, 95% CI = 0.795-0.998, p = 0.046), left atrial diameter (HR = 8.215, 95% CI = 1.557-43.34, p < 0.001), and uric acid concentration (HR = 1.650, 95% CI = 1.063-2.561, p = 0.025) were identified as predictors of atrial high-rate events.

CONCLUSION

LVEF, left atrial diameter, and uric acid level were found to be independent predictors of AHRE in patients with HFrEF. Identifying AHRE is crucial for risk stratification and guiding therapeutic decisions to improve patient outcome.

Assessment of Coronary Artery Disease in Non-Valvular Atrial Fibrillation: Is This Light at the End of the Tunnel?

Non-valvular atrial fibrillation (NVAF) is the most common sustained arrhythmia worldwide, and is associated with significant morbidity and mortality. Increasing life expectancy, coupled with a surge in comorbidity burden, has resulted in a sharp increase in NVAF prevalence over the last three decades. Coronary artery disease (CAD) is an important and clinically relevant risk factor of AF. Concomitant CAD has significant implications for AF management and is a major determinant of the overall outcomes. Shared risk factors, a common pathophysiological basis, and heightened thrombogenesis culminating in cardiovascular adverse events, highlight the close association between the two. The clinical course of AF is worse when associated with CAD, resulting in poor heart rate control, increased propensity to develop stroke and myocardial infarction, increased likelihood of acute presentation with hemodynamic collapse and pulmonary edema, increased bleeding tendencies, and poor response to ablation therapies. Emerging research highlighting the significant role of underlying CAD as an independent predictor of thromboembolic risk has paved the way for the adoption of CAD beyond prior myocardial infarction into the symbol "V" of the CHA2DS2-VASc score. In our opinion, elderly patients aged >65 years with AF, with a history of one or more cardiovascular comorbidities, or evidence of atherosclerosis in other vascular beds should warrant a closer look and a dedicated effort to look for associated CAD. This would allow for a more holistic and comprehensive approach to patients with AF and ultimately help reduce the disease burden and improve the overall outcomes.

Role of epicardial adipose tissue in cardiac remodeling

Epicardial adipose tissue, or epicardial fat, is a type of visceral fat located between the heart and the pericardium. Due to its anatomical proximity to the heart, EAT plays a significant role in both cardiac physiology and pathologies, including cardiac remodeling and cardiovascular diseases (CVD). However, our understanding of how EAT pathology is influenced by risk factors such as obesity and type 2 diabetes mellitus and how altered EAT can drive cardiac remodeling and CVD, remains limited. Herein, we aimed to summarize and discuss the latest findings on EAT and its role in cardiac remodeling, highlighting the outcomes of clinical and observational studies, provide mechanistic insights, and finally introduce emerging therapeutic agents and nutritional guidelines aimed at preventing these conditions.

Clinical decisions for appropriate management of patients with atrial fibrillation

The management of patients with atrial fibrillation (AF) requires intricate clinical decision-making to optimize outcomes. In everyday clinical practice, physicians undergo difficult choices to better manage patients with AF. They need to balance thromboembolic and bleeding risk to focus on patients' symptoms and to manage a variety of multiple comorbidities. In this review, we aimed to explore the multifaceted dimensions of clinical decision-making in AF patients, encompassing the definition and diagnosis of clinical AF, stroke risk stratification, oral anticoagulant therapy selection, consideration of bleeding risk, and the ongoing debate between rhythm and rate control strategies. We will also focus on possible grey zones for the management of AF patients. In navigating this intricate landscape, clinicians must reconcile the dynamic interplay of patient-specific factors, evolving guidelines, and emerging therapies. The review underscores the need for personalized, evidence-based clinical decision-making to tailor interventions for optimal outcomes according to specific AF patient profiles.

Atrial Fibrillation and Heart Failure With Reduced Ejection Fraction: New Assessment of an Old Problem

Atrial fibrillation (AF) and heart failure (HF)-specifically, heart failure with reduced ejection fraction (HFrEF)-often coexist, and each contributes to the propagation of the other. This relationship extends from the mechanistic and physiological to clinical syndromes, quality of life, and long-term cardiovascular outcomes. The risk factors for AF and HF overlap and create a critical opportunity to prevent adverse outcomes among patients at greatest risk for either condition. Increasing recognition of the linkages between AF and HF have led to widespread interest in designing diagnostic, predictive, and interventional strategies targeting all aspects of disease, from identifying genetic predisposition to addressing social determinants of health. Advances across this spectrum culminated in updated multisociety guidelines for management of AF, which includes specific consideration of comorbid AF and HF. This review expands on these guidelines by further highlighting relevant clinical trial findings and providing additional context for the evolving recommendations for management in this important and growing population.

Systematic review and meta-analysis on the impact on outcomes of device algorithms for minimizing right ventricular pacing

AIMS

Physiological activation of the heart using algorithms to minimize right ventricular pacing (RVPm) may be an effective strategy to reduce adverse events in patients requiring anti-bradycardia therapies. This systematic review and meta-analysis aimed to evaluate current evidence on clinical outcomes for patients treated with RVPm algorithms compared to dual-chamber pacing (DDD).

METHODS AND RESULTS

We conducted a systematic search of the PubMed database. The predefined endpoints were the occurrence of persistent/permanent atrial fibrillation (PerAF), cardiovascular (CV) hospitalization, all-cause death, and adverse symptoms. We also aimed to explore the differential effects of algorithms in studies enrolling a high percentage of atrioventricular block (AVB) patients. Eight studies (7229 patients) were included in the analysis. Compared to DDD pacing, patients using RVPm algorithms showed a lower risk of PerAF [odds ratio (OR) 0.74, 95% confidence interval (CI) 0.57-0.97] and CV hospitalization (OR 0.77, 95% CI 0.61-0.97). No significant difference was found for all-cause death (OR 1.01, 95% CI 0.78-1.30) or adverse symptoms (OR 1.03, 95% CI 0.81-1.29). No significant interaction was found between the use of the RVPm strategy and studies enrolling a high percentage of AVB patients. The pooled mean RVP percentage for RVPm algorithms was 7.96% (95% CI 3.13-20.25), as compared with 45.11% (95% CI 26.64-76.38) of DDD pacing.

CONCLUSION

Algorithms for RVPm may be effective in reducing the risk of PerAF and CV hospitalization in patients requiring anti-bradycardia therapies, without an increased risk of adverse symptoms. These results are also consistent for studies enrolling a high percentage of AVB patients.

Atrial cardiomyopathy: An entity of emerging interest in the clinical setting

Since 1995, the concept of atrial cardiomyopathy (ACM) has been associated with myocardial fibrosis. Despite a consensus document in 2016, ACM's definition primarily relies on histopathological findings. The focus on diagnostic criteria for ACM is driven by the potential link to thromboembolic events even independently on atrial fibrillation (AF). The complexity of the mutual relationships between ACM and AF makes difficult any assessment of the thromboembolic risk associated to ACM per se. ACM's thrombogenicity is a multifaceted clinical phenomenon involving electrical, functional, and structural modifications. Factors such as cardiovascular risk factors (e.g., hypertension), common cardiac comorbidities (e.g., heart failure), and extracardiac conditions (e.g., neuromuscular disorders) can promote atrial derangement, triggering atrial fibrillation (AF) and increasing the risk of thromboembolic events. Several diagnostic methods are available to detect the key features of ACM, including electrical changes assessed by surface and intracavitary ECG, and structural and functional alterations evaluated through echocardiography and cardiac magnetic resonance (CMR). These methods can be complemented by electro-anatomical mapping (EAM) to enhance the accuracy of myocardial tissue characterization and assessment of atrial fibrosis. Although certain clinical conditions (e.g., atrial high-rate episodes, AHREs; embolic stroke of undetermined source, ESUS) often exhibit atrial alterations in their thromboembolic presentations, recent randomized trials have failed to demonstrate the benefits of oral anticoagulation in patients with ACM without AF. However, ACM constitutes the substrate for the development of AF, as proposed in the AF European guidelines under the 4S-AF scheme. This review emphasizes the lack of a diagnostic gold standard and the need for clinical criteria for ACM, aiming to better understand the potential therapeutic implications of atrial structural and functional derangements, even in the absence of clinical evidence of AF.