Prevention of atrial fibrillation onset by beta-blocker treatment in heart failure: a meta-analysis

Implications of Atrial Fibrillation for Guideline-Directed Therapy in Patients With Heart Failure: JACC State-of-the-Art Review

Atrial fibrillation (AF) and heart failure (HF) are common cardiovascular conditions that frequently coexist. Among patients with HF, more than one-half also have AF. Both are associated with significant morbidity and mortality. Moreover, the prevalence of each is increasing globally, and this trend is expected to continue owing to an aging population and increased life expectancy. Diagnosis of AF in a patient with HF is associated with greater symptom burden, more frequent hospitalizations, and a worse prognosis. Guideline-directed medical therapy (GDMT) for HF can affect the incidence of AF. Once present, AF can influence the efficacy of some components of GDMT for HF. In this review, we discuss the effect of GDMT for HF across the spectrum of ejection fraction on prevention of AF as well as the benefit of GDMT in patients with vs without AF.

Risk factors modification in atrial fibrillation: a brief review

INTRODUCTION

Atrial fibrillation (AF) is a supraventricular arrhythmia characterized by fibrillatory waves in the atria with an irregular ventricular rhythm. It is the most common arrhythmia treated in clinical practice. AF is associated with approximately five-fold increase in risk of cerebrovascular accident (stroke) and two-fold increase in cognitive dysfunction and all-cause mortality.

AREAS COVERED

Multiple risk factors have been identified for development of AF including age, hypertension, diabetes, and obesity. Primary and secondary prevention strategies aimed at reducing the incidence of AF can have a dramatic clinical and economic impact. Multiple studies have shown that lifestyle interventions can reduce predisposing factors, reverse the pathophysiology behind AF, and decrease disease burden. In this brief review we aim at exploring the current state of knowledge regarding risk factor modifications that decrease incidence and prevalence of AF.

EXPERT OPINION

This is an evolving field of research and further studies to elucidate the magnitude of effect of these interventions as well as the pathophysiological mechanisms driving these effects are underway.

Triggers of Atrial Fibrillation in the Geriatric Medical Intensive Care Unit: An Observational Study

Background

Atrial fibrillation (AF) is a common arrhythmia in the non-cardiac intensive care unit (ICU). However, data concerning AF incidence and predictors in such populations are scarce and controversial. The study aimed to investigate the contributing factors of new-onset AF in elderly patients within the medical intensive care setting.

Methods

Patients admitted to ICU during a 6-month period were prospectively studied. Patients admitted for short period postoperative monitoring and patients with chronic or paroxysmal AF were excluded. The conditions involved as AF risk factors or "triggers" from demographic data, history, and echocardiography were recorded. Acute Physiology and Chronic Health Evaluation II score was calculated. Electrolytes including some trace elements (zinc, copper, and magnesium) were analyzed.

Results

The study included 142 patients (49% females). Mean age was 69.5 ± 7.3 years. AF was observed in 12%. Diagnosis of pneumonia (P < 0.001), low copper (P < 0.0001) and low zinc levels (P < 0.0001) was significantly associated with the occurrence of AF. By multivariate analysis, they remained statistically significant (odds ratio, 7.0; 95% confidence interval, 2.0 - 24.6; P < 0.01).

Conclusions

A significant fraction of ICU elderly patients manifests AF. The relevant factors contributing to AF incidence in the elderly are pneumonia and low zinc and low copper.

Autonomic Nervous System and Cardiac Metabolism: Links Between Autonomic and Metabolic Remodeling in Atrial Fibrillation

Simultaneous activation of the sympathetic and parasympathetic nervous systems is crucial for the initiation of paroxysmal atrial fibrillation (AF). However, unbalanced activation of the sympathetic system is characteristic of autonomic remodeling in long-standing persistent AF. Moreover, the adrenergic activation-induced metabolic derangements provide a milieu for acute AF and promote the transition from the paroxysmal to the persistent phase of AF. On the other hand, cholinergic activation ameliorates the maladaptive metabolic remodeling in the face of metabolic challenges. Selective inhibition of the sympathetic system and restoration of the balance of the cholinergic system by neuromodulation is emerging as a novel nonpharmacologic strategy for managing AF. This review explores the link between cardiac autonomic and metabolic remodeling and the potential roles of different autonomic modulation strategies on atrial metabolic aberrations in AF.

Beta blockers for the treatment of arrhythmias: Bisoprolol - a systematic review

OBJECTIVES

Beta blockers have long been successfully used for the treatment of both supraventricular and ventricular arrhythmias. However, differences exist between their chemical structure, pharmacokinetic and pharmacodynamic properties (absorption, bioavailability, metabolism, hydrophilic or lipophilic character, selective or non-selective nature, the presence or absence of intrinsic sympathomimetic activity), which may confer different antiarrhythmic properties to different beta blockers. The aim of this study was to analyze the current existing evidence for bisoprolol for the treatment of both supraventricular and ventricular arrhythmias.

MATERIAL AND METHODS

Using the keywords "bisoprolol" and "arrhythmias" or "atrial fibrillation" or "ventricular tachycardia" or "premature ventricular complexes" or "ventricular fibrillation", the Medline database was searched for articles in English or French until April 2020 assessing the role of bisoprolol in the treatment of arrhythmias. Data was then analyzed according to the type of arrhythmia treated and the quality of evidence using the GRADE approach.

RESULTS

A total of 325 studies were identified, of which 28 were considered relevant to the current topic. Among these studies, 19 assessed the role of bisoprolol for the treatment of supraventricular arrhythmias, 8 its role in treating ventricular arrhythmias and 1 its role in supraventricular and ventricular arrhythmias. The quality of evidence varied from low (7 studies) to high (5 studies).

CONCLUSION

Current evidence exists supporting the use of bisoprolol for the treatment of supraventricular arrhythmias, especially for rate control during atrial fibrillation. Evidence also exists for its efficacy in the treatment of ventricular arrhythmias, both in primary and in secondary prevention.

Management of Atrial Fibrillation in Patients 75 Years and Older: JACC State-of-the-Art Review

The prevalence of atrial fibrillation (AF) is increasing as the population ages. AF treatment-related complications also increase markedly in older adults (defined as ≥75 years of age for this review). The older AF population has a high risk of stroke, bleeding, and death. Syncope and fall-related injuries are the most common reasons for nonprescription of oral anticoagulation (OAC), and are more common in older adults when OACs are used with antiarrhythmic drugs. Digoxin may be useful for rate control, but associations with increased mortality limit its use. Beyond rate and rhythm control considerations, stroke prophylaxis is critical to AF management, and the benefits of direct OACs, compared with warfarin, extend to older adults. Invasive procedures such as AF catheter ablation, pacemaker implantation/atrioventricular junction ablation, and left atrial appendage occlusion may be useful in appropriately selected cases. However, older adults have generally been under-represented in clinical trials.

Atrial Fibrillation and Hypertension: "Quo Vadis"

Hypertension is one of the most well-established risk factors for atrial fibrillation. Long-standing untreated hypertension leads to structural remodeling and electrophysiologic alterations causing an atrial myopathy that forms a vulnerable substrate for the development and maintenance of atrial fibrillation. Hypertension-induced hemodynamic, inflammatory, hormonal, and autonomic changes all appear to be important contributing factors. Furthermore, hypertension is also associated with several atrial fibrillation-related comorbidities. As such, hypertension may represent an important target for therapy in atrial fibrillation. Clinicians should be aware of pitfalls of the blood pressure measurement in atrial fibrillation. While the auscultatory method is preferred, the use of automated devices appears to be an acceptable method in the ambulatory setting. There are pathophysiologic bases and emerging clinical evidence suggesting the benefit of renin-angiotensin system inhibition in risk reduction of atrial fibrillation development particularly in patients with left ventricular hypertrophy or left ventricular dysfunction. A better understanding of hypertension's pathophysiologic link to atrial fibrillation may lead to the development of novel therapies for the primary prevention of atrial fibrillation. Finally, future studies are needed to address optimal blood pressure goal to minimize the risk of atrial fibrillation-related complications.

Guide de Pratique Clinique. Prise en charge de l’hypertension artérielle chez l’adulte en Tunisie

Ce document a été réalisé dans le cadre d'une collaboration entre l'Instance Nationale de l’Évaluation et de l'Accréditation en Santé (INEAS), la Société Tunisienne de Cardiologie et de Chirurgie Cardiovasculaire (STCCCV) et la Caisse Nationale d’Assurance Maladie (CNAM).

The Modifiable Risk Factors of Uncontrolled Hypertension in Stroke: A Systematic Review and Meta-Analysis

OBJECTIVE

This review aimed at figuring out the risk factors of uncontrolled hypertension in stroke.

METHOD

This study systematically analyzed the hypertension risk factors available in the ProQuest, EBSCO, and PubMed databases published between 2010 and December 2019. The risk factors' pooled odds ratio (POR) included in this research was calculated using both fixed and random-effect models. The meta-data analysis was processed using the Review Manager 5.3 (Rev Man 5.3).

RESULT

Of 1868 articles, seven studies were included in this review searched using specific keywords. Based on the analysis results, there were 7 risk factors of uncontrolled hypertension in stroke: medication nonadherence (POR = 2.23 [95% CI 1.71-2.89], p = 0.342; I 2 = 6.7%), use of antihypertensive drugs (POR = 1.13 [95% CI 1.19-1.59, p = 0.001; I 2 = 90.9%), stage of hypertension (POR = 1.14 [95% CI 1.02-1.27], p = <0.001; I 2 = 97.1%), diabetes mellitus (POR = 0.71 [95% CI 0.52-0.99], p = <0.001; I 2 = 96.5%), atrial fibrillation (POR = 1.74 [95% CI 1.48-2.04)], p = <0.001; I 2 = 93.1%), triglycerides (POR = 1.47 [95% CI 1.23-1.75], p = 0.879; I 2 = 0%), and age (POR = 1.03 [95% CI 0.89-1.18], p = <0.001; I 2 = 97.5%]. There were no bias publications among studies. Medication nonadherence and triglycerides had homogeneous variations, while the others had heterogeneous variations.

CONCLUSION

Medication nonadherence, triglycerides, stage of hypertension, atrial fibrillation, and use of antihypertensive drugs significantly affect the uncontrolled hypertension in stroke.

Autonomic Dysfunction and Neurohormonal Disorders in Atrial Fibrillation

Atrial fibrillation (AF) is the most commonly diagnosed arrhythmia and eludes an efficacious cure despite an increasing prevalence and a significant association with morbidity and mortality. In addition to an array of clinical sequelae, the origins and propagation of AF are multifactorial. In recent years, the contribution from the autonomic nervous system has been an area of particular interest. This review highlights the relevant physiology of autonomic and neurohormonal contributions to AF origin and maintenance, the current state of the literature on targeted therapies, and the path forward for clinical interventions.

The role of β-adrenergic system remodeling in human heart failure: A mechanistic investigation

β-adrenergic receptor antagonists (β-blockers) are extensively used to improve cardiac performance in heart failure (HF), but the electrical improvements with these clinical treatments are not fully understood. The aim of this study was to analyze the electrophysiological effects of β-adrenergic system remodeling in heart failure with reduced ejection fraction and the underlying mechanisms. We used a combined mathematical model that integrated β-adrenergic signaling with electrophysiology and calcium cycling in human ventricular myocytes. HF remodeling, both in the electrophysiological and signaling systems, was introduced to quantitatively analyze changes in electrophysiological properties due to the stimulation of β-adrenergic receptors in failing myocytes. We found that the inotropic effect of β-adrenergic stimulation was reduced in HF due to the altered Ca²⁺ dynamics resulting from the combination of structural, electrophysiological and signaling remodeling. Isolated cells showed proarrhythmic risk after sympathetic stimulation because early afterdepolarizations appeared, and the vulnerability was greater in failing myocytes. When analyzing coupled cells, β-adrenergic stimulation reduced transmural repolarization gradients between endocardium and epicardium in normal tissue, but was less effective at reducing these gradients after HF remodeling. The comparison of the selective activation of β-adrenergic isoforms revealed that the response to β₂-adrenergic receptors stimulation was blunted in HF while β₁-adrenergic receptors downstream effectors regulated most of the changes observed after sympathetic stimulation. In conclusion, this study was able to reproduce an altered β-adrenergic activity on failing myocytes and to explain the mechanisms involved. The derived predictions could help in the treatment of HF and guide in the design of future experiments.

Chronic dantrolene treatment attenuates cardiac dysfunction and reduces atrial fibrillation inducibility in a rat myocardial infarction heart failure model

Background

Cardiac ryanodine receptor 2 (RyR2) dysfunction and elevated diastolic Ca²⁺ leak have been linked to arrhythmogenesis not only in inherited arrhythmia syndromes but also in acquired forms of heart disease including heart failure (HF) and atrial fibrillation (AF). Thus, stabilizing RyR2 may exert therapeutic effects in these conditions.

Objective

The purpose of this study was to investigate the effects of stabilizing RyR2 with chronic dantrolene treatment on HF development and AF inducibility in a myocardial infarction (MI)-induced HF model in rats.

Methods

MI was induced in adult Sprague-Dawley rats by ligation of the left anterior descending coronary artery. Two weeks after MI surgery, rats with large MI (≥40%) were randomly assigned to MI-vehicle (n = 14) or MI-dantrolene (10 mg/kg/d; n = 13) groups. Sham-surgery rats (n = 7) served as controls.

Results

Compared to the MI-vehicle group, 4-week dantrolene treatment significantly improved cardiac function, with increased left ventricular (LV) fractional shortening (19.48% ± 3.61% vs 15.43% ± 2.65%; P <.01), and decreased LV end-diastolic pressure (12.58 ± 8.52 mm Hg vs 21.91 ± 7.25 mm Hg; P <.01), left atrial diameter (4.97 ± 0.75 mm vs 6.09 ± 1.53 mm; P <.05), and fibrosis content (6.42% ± 0.78% vs 9.76% ± 2.25%; P <.001). Dantrolene significantly decreased AF inducibility (69% in MI-vehicle vs 23% in MI-dantrolene; P <.05). Dantrolene treatment was associated with reduced RyR2 phosphorylation and favorably altered gene expression involving ion channels, sympathetic signaling, oxidative stress, and inflammatory markers.

Conclusion

Chronic dantrolene treatment attenuated LV dysfunction and reduced AF inducibility, which was associated with decreased RyR2 phosphorylation and normalization of many adverse changes in gene expression. Thus, stabilizing RyR2 with chronic dantrolene treatment is a promising novel strategy for decreasing AF in HF.

Novel beta-blocker pretreatment prevents alcohol-induced atrial fibrillation in a rat model

Background

A case report published in 2019 described a patient who presented with difficult-to-manage atrial fibrillation (AF) that consistently was associated with alcohol consumption. After the patient did not respond to drug therapy, a novel beta-blocker (BB) pretreatment regimen initiated immediately before alcohol consumption successfully prevented AF occurrence.

Objective

The purpose of this study was to test the hypothesis that a novel prophylactic BB therapy given before alcohol consumption could prevent AF in a rat model.

Methods

An alcohol-induced AF model was developed in adult Sprague-Dawley rats of both sexes by administering alcohol (2 g/kg intraperitoneal [IP]) once every other day for a total of 4 times. Three groups were enrolled: alcohol (EtOH; n = 10); alcohol plus BB (metoprolol 50 mg/kg IP) pretreatment (EtOH+BB; n = 10); and control (n = 9). Cardiac function (assessed by echocardiography and left ventricular hemodynamics) and in vivo atrial electrophysiology and AF inducibility tests were performed 24 hours after the last injection.

Results

All but 1 rat completed the study. Alcohol exposure did not significantly impact cardiac function and the atrial effective refractory period. However, alcohol exposure significantly increased AF inducibility [median (first and third quartile [Q1–Q3]) 0% (0%–0%) in control vs 60% (25%–100%) in the EtOH group; P <.05] and AF duration [0 second (0–0 second) in control vs 0.81 second (0.24–3.67 seconds) in the EtOH group; P <.05]. Compared to the EtOH group, the EtOH+BB group had significantly reduced AF inducibility [0% (0%–22.5%); P <.05] and duration [0 second (0–0.2 second); P <.05].

Conclusion

Metoprolol pretreatment before alcohol administration significantly decreased AF induction in rats. These findings suggest that BB pretreatment is a promising prophylaxis regimen for alcohol-induced AF.

Lifestyle and Risk Factor Modification for Reduction of Atrial Fibrillation: A Scientific Statement From the American Heart Association

Atrial fibrillation (AF), the most common sustained cardiac arrhythmia, is associated with substantial morbidity, mortality, and healthcare use. Great strides have been made in stroke prevention and rhythm control strategies, yet reducing the incidence of AF has been slowed by the increasing incidence and prevalence of AF risk factors, including obesity, physical inactivity, sleep apnea, diabetes mellitus, hypertension, and other modifiable lifestyle-related factors. Fortunately, many of these AF drivers are potentially reversible, and emerging evidence supports that addressing these modifiable risks may be effective for primary and secondary AF prevention. A structured, protocol-driven multidisciplinary approach to integrate lifestyle and risk factor management as an integral part of AF management may help in the prevention and treatment of AF. However, this aspect of AF management is currently underrecognized, underused, and understudied. The purpose of this American Heart Association scientific statement is to review the association of modifiable risk factors with AF and the effects of risk factor intervention. Implementation strategies, care pathways, and educational links for achieving impactful weight reduction, increased physical activity, and risk factor modification are included. Implications for clinical practice, gaps in knowledge, and future directions for the research community are highlighted.

Pharmacological management of atrial fibrillation in patients with heart failure with reduced ejection fraction: review of current knowledge and future directions

Introduction: Both heart failure with reduced ejection fraction (HFrEF) and atrial fibrillation (AF) independently cause significant morbidity and mortality. The two conditions commonly coexist and AF in the setting of HFrEF is associated with worse mortality, hospitalizations, and quality of life compared to HFrEF without AF. Despite the large burden of these conditions, there is no clear optimal management strategy for when they occur together.Areas covered: This review focuses on the pharmacological management of AF in HFrEF. Studies were identified through PubMed search of relevant keywords. The authors review key clinical trials that have influenced management strategies and guidelines. The authors focus on the classes of drugs used to treat AF for both rate and rhythm control strategies including beta-blockers, digoxin, amiodarone, and dofetilide. Additionally, the authors discuss select non-antiarrhythmic medications that affect AF in HFrEF. The authors highlight the strengths and weakness of the data supporting the use of these medications and suggest future directions.Expert opinion: The pharmacological treatment of AF in HFrEF will need further refinement alongside the emerging role of catheter ablation. Novel HF medications and antiarrhythmics offer new tools to prevent the development of AF, as well as for rate and rhythm control strategies.

Comparison of continuous 24-h and 14-day monitoring for detection of otherwise unknown atrial fibrillation: a registry to identify Japanese concealed atrial fibrillation (REAL-AF)-based study

Early detection of atrial fibrillation (AF) is desirable for preventing strokes. Not only does AF often go undetected in patients being followed up for various disease conditions, but the optimal detection method also remains to be elucidated. In a prospective observational study of 24-h Holter monitoring versus 14-day external loop recording performed for detection of previously undiagnosed AF in 868 Japanese outpatients (aged 75 ± 6 years), with a CHA2DS2-vasc score ≥ 1, but no prior AF episodes, AF was detected during the initial monitoring period in 16 (1.8%) patients, in 7 (1.1% [7/645]) by 24-h monitoring and 9 (4.0% [9/223]) by 14-day monitoring (P = 0.005), and overall in 32 (3.7%) during the 1-year study period. Absence of a beta-blocker therapy and the serum N-terminal pro-brain natriuretic peptide level were independent predictors of a new detection of AF. Oral anticoagulation (OAC) therapy was given to 22 (69%) of the 32 patients in whom AF was detected, and no difference in the incidence of subsequent major adverse events was found between the patients managed with and without oral OAC therapy. Previously unknown AF was documented at a prevalence of 3.7% per year among Japanese with a notable CHA₂DS₂-VASc score, and 14-day external loop monitoring was significantly more effective for detection of the disorder. A large-scale prospective AF screening study conducted to clarify the type or types of patients who would benefit from "early" OAC therapy for primary stroke prevention is warranted.

Antiarrhythmic mechanisms of beta blocker therapy

Sympathetic activity plays an important role in modulation of cardiac rhythm. Indeed, while exerting positive tropic effects in response to physiologic and pathologic stressors, β-adrenergic stimulation influences cardiac electrophysiology and can lead to disturbances of the heart rhythm and potentially lethal arrhythmias, particularly in pathological settings. For this reason, β-blockers are widely utilized clinically as antiarrhythmics. In this review, the molecular mechanisms of β-adrenergic action in the heart, the cellular and tissue level cardiac responses to β-adrenergic stimulation, and the clinical use of β-blockers as antiarrhythmic agents are reviewed. We emphasize the complex interaction between cardiomyocyte signaling, contraction, and electrophysiology occurring over multiple time- and spatial-scales during pathophysiological responses to β-adrenergic stimulation. An integrated understanding of this complex system is essential for optimizing therapies aimed at preventing arrhythmias.

Bucindolol for the Maintenance of Sinus Rhythm in a Genotype-Defined HF Population: The GENETIC-AF Trial

OBJECTIVES

The purpose of this study was to compare the effectiveness of bucindolol with that of metoprolol succinate for the maintenance of sinus rhythm in a genetically defined heart failure (HF) population with atrial fibrillation (AF).

BACKGROUND

Bucindolol is a beta-blocker whose unique pharmacologic properties provide greater benefit in HF patients with reduced ejection fraction (HFrEF) who have the beta₁-adrenergic receptor (ADRB1) Arg389Arg genotype.

METHODS

A total of 267 HFrEF patients with a left ventricular ejection fraction (LVEF) <0.50, symptomatic AF, and the ADRB1 Arg389Arg genotype were randomized 1:1 to receive bucindolol or metoprolol therapy and were up-titrated to target doses. The primary endpoint of AF or atrial flutter (AFL) or all-cause mortality (ACM) was evaluated by electrocardiogram (ECG) during a 24-week period.

RESULTS

The hazard ratio (HR) for the primary endpoint was 1.01 (95% confidence interval [CI]: 0.71 to 1.42), but trends for bucindolol benefit were observed in several subgroups. Precision therapeutic phenotyping revealed that a differential response to bucindolol was associated with the interval of time from the initial diagnoses of AF and HF to randomization and with the onset of AF relative to that of the initial HF diagnosis. In a cohort whose first AF and HF diagnoses were <12 years prior to randomization, in which AF onset did not precede HF by more than 2 years (n = 196), the HR was 0.54 (95% CI: 0.33 to 0.87; p = 0.011).

CONCLUSIONS

Pharmacogenetically guided bucindolol therapy did not reduce the recurrence of AF/AFL or ACM compared to that of metoprolol therapy in HFrEF patients, but populations were identified who merited further investigation in future phase 3 trials.

Mechanisms of Improved Mortality Following Ablation: Does Ablation Restore Beta-Blocker Benefit in Atrial Fibrillation/Heart Failure?

Observational trials have shown that atrial fibrillation ablation favorably impacts long-term outcomes in systolic heart failure. These outcomes have been confirmed by randomized prospective trials highlighting the favorable impact of ablation on left ventricular function and remodeling, risk of heart failure hospitalization, and mortality. Ablation along with established heart failure medications is new and supported conceptually by the value of restoring sinus rhythm, avoiding long-term antiarrhythmic drugs, and minimizing drug-drug interactions. Observational data suggest a potential long-term benefit of beta-blockers with ablation that becomes augmented as follow-up is extended from 1 to 5 years.

Evaluation of the protective effects of β-blockers in the management of acute exacerbations of chronic obstructive pulmonary disease

WHAT IS KNOWN AND OBJECTIVE

The purpose of this study was to evaluate the association between early β-blocker continuation and major inpatient events in patients hospitalized for an acute exacerbation of chronic obstructive pulmonary disease (AECOPD).

METHODS

This single centre, retrospective, investigational review board approved cohort study evaluated patients admitted for a primary diagnosis of AECOPD. Patients were evaluated based on early continuation of a β-blocker whether a β-blocker was initiated within 24 hours of admission and continued for at least 72 hours. Patients with AECOPD who did not receive β-blockers were assigned to the control group. Major inpatient events were a composite outcome composed of arrhythmias, myocardial infarction (MI) and death. Safety data were collected on the incidences of bradycardia, bronchospasms and hypotension.

RESULTS AND DISCUSSION

Of the 96 patients admitted for AECOPD, fifty-five patients were included in the early β-blocker group and forty-one patients in the control group. Early β-blocker utilization was associated with a significantly lower rate of major inpatient events compared with the control group (40% vs 80.5%; P < 0.001). Arrhythmias were significantly less common in the early β-blocker group (30.9% vs 65.9%; P = 0.001); however, there were no significant differences in the rates of MI (9.1% vs 14.6%; P = 0.54), death (0 vs 0) or safety outcomes between groups.

WHAT IS NEW AND CONCLUSION

β-blocker therapy could result in a paradigm shift in managing chronic obstructive pulmonary disease patients from a true cardiopulmonary approach. This retrospective cohort study demonstrated early β-blocker continuation in patients admitted for an AECOPD was associated with less major inpatient events, primarily arrhythmias.

2018 ESC/ESH Guidelines for the management of arterial hypertension: The Task Force for the management of arterial hypertension of the European Society of Cardiology and the European Society of Hypertension: The Task Force for the management of arterial hypertension of the European Society of Cardiology and the European Society of Hypertension

: Document reviewers: Guy De Backer (ESC Review Co-ordinator) (Belgium), Anthony M. Heagerty (ESH Review Co-ordinator) (UK), Stefan Agewall (Norway), Murielle Bochud (Switzerland), Claudio Borghi (Italy), Pierre Boutouyrie (France), Jana Brguljan (Slovenia), Héctor Bueno (Spain), Enrico G. Caiani (Italy), Bo Carlberg (Sweden), Neil Chapman (UK), Renata Cifkova (Czech Republic), John G. F. Cleland (UK), Jean-Philippe Collet (France), Ioan Mircea Coman (Romania), Peter W. de Leeuw (The Netherlands), Victoria Delgado (The Netherlands), Paul Dendale (Belgium), Hans-Christoph Diener (Germany), Maria Dorobantu (Romania), Robert Fagard (Belgium), Csaba Farsang (Hungary), Marc Ferrini (France), Ian M. Graham (Ireland), Guido Grassi (Italy), Hermann Haller (Germany), F. D. Richard Hobbs (UK), Bojan Jelakovic (Croatia), Catriona Jennings (UK), Hugo A. Katus (Germany), Abraham A. Kroon (The Netherlands), Christophe Leclercq (France), Dragan Lovic (Serbia), Empar Lurbe (Spain), Athanasios J. Manolis (Greece), Theresa A. McDonagh (UK), Franz Messerli (Switzerland), Maria Lorenza Muiesan (Italy), Uwe Nixdorff (Germany), Michael Hecht Olsen (Denmark), Gianfranco Parati (Italy), Joep Perk (Sweden), Massimo Francesco Piepoli (Italy), Jorge Polonia (Portugal), Piotr Ponikowski (Poland), Dimitrios J. Richter (Greece), Stefano F. Rimoldi (Switzerland), Marco Roffi (Switzerland), Naveed Sattar (UK), Petar M. Seferovic (Serbia), Iain A. Simpson (UK), Miguel Sousa-Uva (Portugal), Alice V. Stanton (Ireland), Philippe van de Borne (Belgium), Panos Vardas (Greece), Massimo Volpe (Italy), Sven Wassmann (Germany), Stephan Windecker (Switzerland), Jose Luis Zamorano (Spain).The disclosure forms of all experts involved in the development of these Guidelines are available on the ESC website www.escardio.org/guidelines.

Failing Hearts Are More Vulnerable to Sympathetic, but Not Vagal Stimulation-Induced, Atrial Fibrillation-Ameliorated with Dantrolene Treatment

BACKGROUND

Both vagal (VS) and sympathetic (SS) stimulations can increase atrial fibrillation (AF) inducibility, with VS being known as more arrhythmogenic in normal hearts. Heart failure (HF) results in autonomic dysfunction (characterized by sympathetic activation and vagal withdrawal) and is associated with an increased AF incidence. This study investigated whether failing hearts, compared with normal control hearts, respond differently to autonomic stimulation-induced AF arrhythmogenesis and the effect of dantrolene on SS-enhanced AF in HF.

METHODS AND RESULTS

A rat myocardial infarction (MI) HF model was used. In experiment 1, AF inducibility was compared in 9 MI-HF rats versus 10 sham-control animals at baseline, during VS, and during SS with isoproterenol infusion. In experiment 2, dantrolene treatment (n = 8) was compared with placebo-control (n = 9) on SS-induced AF inducibility in HF. Compared with the sham-control, baseline AF inducibility was higher in the MI-HF group. AF inducibility was augmented in both groups by autonomic stimulation. However, under VS the increased magnitude was less in the MI-HF group (49% ± 11% vs 80% ± 10%; P = .029), but under SS was significantly more (53% ± 8% vs 6% ± 7%; P < .001), compared with sham-control. Dantrolene significantly attenuated SS-enhanced AF in HF (69% ± 6% vs 29% ± 9%; P = .006).

CONCLUSIONS

Failing hearts are less sensitive to VS, but more vulnerable to SS-induced AF compared with normal-control hearts. Dantrolene can significantly attenuate SS-enhanced AF in HF, indicating that cardiac ryanodine receptor dysfunction may play a critical role in SS-enhanced AF in HF, and stabilizing leaky ryanodine receptor with the use of dantrolene may be a new treatment option in this condition.

A genotype-directed comparative effectiveness trial of Bucindolol and metoprolol succinate for prevention of symptomatic atrial fibrillation/atrial flutter in patients with heart failure: Rationale and design of the GENETIC-AF trial

BACKGROUND

Few therapies are available for the safe and effective treatment of atrial fibrillation (AF) in patients with heart failure. Bucindolol is a non-selective beta-blocker with mild vasodilator activity previously found to have accentuated antiarrhythmic effects and increased efficacy for preventing heart failure events in patients homozygous for the major allele of the ADRB1 Arg389Gly polymorphism (ADRB1 Arg389Arg genotype). The safety and efficacy of bucindolol for the prevention of AF or atrial flutter (AFL) in these patients has not been proven in randomized trials.

METHODS/DESIGN

The Genotype-Directed Comparative Effectiveness Trial of Bucindolol and Metoprolol Succinate for Prevention of Symptomatic Atrial Fibrillation/Atrial Flutter in Patients with Heart Failure (GENETIC-AF) trial is a multicenter, randomized, double-blinded "seamless" phase 2B/3 trial of bucindolol hydrochloride versus metoprolol succinate, for the prevention of symptomatic AF/AFL in patients with reduced ejection fraction heart failure (HFrEF). Patients with pre-existing HFrEF and recent history of symptomatic AF are eligible for enrollment and genotype screening, and if they are ADRB1 Arg389Arg, eligible for randomization. A total of approximately 200 patients will comprise the phase 2B component and if pre-trial assumptions are met, 620 patients will be randomized at approximately 135 sites to form the Phase 3 population. The primary endpoint is the time to recurrence of symptomatic AF/AFL or mortality over a 24-week follow-up period, and the trial will continue until 330 primary endpoints have occurred.

CONCLUSIONS

GENETIC-AF is the first randomized trial of pharmacogenetic guided rhythm control, and will test the safety and efficacy of bucindolol compared with metoprolol succinate for the prevention of recurrent symptomatic AF/AFL in patients with HFrEF and an ADRB1 Arg389Arg genotype. (ClinicalTrials.govNCT01970501).

The Real Role of β-Blockers in Daily Cardiovascular Therapy

The role of β-adrenoceptor antagonists (β-blockers) in cardiovascular therapy has been subject to diverse trends and changes over the decades. With the advent of a wide variety of excellent drugs for the treatment of antihypertension, β-blockers have been relegated from the first-line treatment of essential hypertension. However, they remain the drugs of first choice in recommendations from the respective medical societies for heart failure, coronary artery disease, and atrial fibrillation as well as in hypertension complicated with heart failure, angina pectoris, or prior myocardial infarction. When indicated, cardioselective β-blockers should be prescribed in patients with diabetes mellitus or chronic obstructive pulmonary disease. We review the available evidence for the use of β-blockers in clinical conditions in which recommendations can be made for everyday practice.

Supraventricular premature beats and risk of new-onset atrial fibrillation in coronary artery disease

INTRODUCTION

The significance of premature atrial contraction (PAC) count and supraventricular runs (SVR) for the risk of development of new-onset atrial fibrillation (AF) in patients with coronary artery disease (CAD) is not well established.

METHODS

The Innovation to Reduce Cardiovascular Complications of Diabetes at the Intersection (ARTEMIS) study cohort consisted of 1,946 patients with CAD who underwent clinical and echocardiographic examinations, 24-hour ambulatory ECG monitoring, and laboratory tests. After excluding patients who were not in sinus rhythm at baseline or were lost from the follow-up, the present study included 1,710 patients. SVR was defined as at least four PACs in a row with a duration <30 seconds.

RESULTS

During a follow-up for an average 5.6 ± 1.5 years, new-onset AF was identified in 143 (8.4%) patients. In the univariate analysis, both SVR and PAC count were associated with the development of new-onset AF. When SVR and PAC count were adjusted with the established AF risk markers of the modified CHARGE-AF model in the Cox multivariate regression analysis, both parameters remained significant predictors of the occurrence of new-onset AF (HR = 2.529, 95 % CI = 1.763-3.628, P ˂ 0.001 and HR = 8.139 for ≥1,409 PACs [the fourth quartile] vs. ≤507 PACs [the first quartile], 95 % CI = 3.967-16.696, P ˂ 0.001, respectively). Together these parameters improved the C-index of the established AF risk model from 0.649 to 0.718, P < 0.001.

CONCLUSION

Including SVR and PAC count to the established AF risk model improves the discrimination accuracy in predicting AF in patients with CAD.

Efficacy of Intravenous Administration of Landiolol in Patients With Acute Heart Failure and Supraventricular Tachyarrhythmia

BACKGROUND

Patients with acute heart failure (HF) complicated by supraventricular tachyarrhythmia (SVT) often receive continuous intravenous infusion of landiolol or diltiazem for rate control. It is unclear whether the interval from initiation of infusion to commencement of oral beta-blocker (BB) therapy differs for these two drugs.

METHODS

From January 2013 to July 2015, 94 consecutive patients were hospitalized for acute HF complicated by SVT. After 35 patients were excluded, the remaining 59 were divided into groups treated with diltiazem or landiolol. We investigated the blood pressure, heart rate, New York Heart Association classification, brain natriuretic peptide, chest X-ray film, echocardiographic findings (ejection fraction (EF)), time until commencement of oral BB therapy, and hospital stay.

RESULTS

There were no significant between-group differences of heart rate, blood pressure, or the severity of HF. The time until commencing oral BB therapy was significantly shorter in the landiolol group compared with the diltiazem group (median: 2 vs. 4 days, P = 0.002), but there was no significant difference in hospital stay. This interval was significantly shorter in patients with a reduced EF in the landiolol group (median: 2 days) compared with those with a reduced EF in the diltiazem group (median: 5 days, P = 0.008), and patients with a preserved EF in the landiolol group tended to have a shorter interval (median: 2 days) than those with a preserved EF in the diltiazem group (median: 4 days, P = 0.092).

CONCLUSIONS

Switching to oral BBs was accomplished earlier with landiolol than with diltiazem.

β1-Adrenergic receptor Arg389Gly polymorphism affects the antiarrhythmic efficacy of flecainide in patients with coadministration of β-blockers

OBJECTIVE

β1-Adrenergic receptor (β1-AR) stimulation modulates the antiarrhythmic activities of sodium channel blockers. The β1-AR Gly389 variant shows a marked decrease in agonist-stimulated cyclic AMP production compared with that of the wild-type Arg389 in vitro. We investigated whether the Arg389Gly polymorphism affects the efficacy of flecainide, a typical sodium channel blocker, in patients with or without coadministration of β-blockers.

METHODS

The effects of the β1-AR Arg389Gly polymorphism on the antiarrhythmic efficacy of flecainide were compared between with and without coadministered β-blockers in 159 patients with supraventricular tachyarrhythmia. The antiarrhythmic efficacy of flecainide was assessed for at least 2 months by evaluating symptomatology, 12-lead ECGs, and Holter monitoring results.

RESULTS

Genetic differences in the antiarrhythmic efficacy of flecainide were observed in patients with coadministration of β-blockers. Tachyarrhythmia was well controlled in 60% of Arg389-homozygotes, 30% of Gly389-heterozygotes, and 0% of Gly389-homozygotes (P=0.001). In contrast, no difference in the antiarrhythmic efficacy was observed among the three genotypes in the patients without coadministration of β-blockers (64, 70, and 60%, respectively). Heart rate in tachyarrhythmia in patients treated with flecainide was significantly higher in Gly389 carriers than in Arg389-homozygotes (P=0.013).

CONCLUSION

The Gly389 polymorphism decreased the antiarrhythmic efficacy of flecainide when coadministered with β-blockers. The results indicate that the Arg389Gly polymorphism may play an important role in predicting the efficacy of flecainide in patients with coadministration of β-blockers.

Treatment of Patients With Atrial Fibrillation and Heart Failure With Reduced Ejection Fraction

Atrial fibrillation (AF) and heart failure with reduced ejection fraction (HFrEF) frequently coexist, and each complicates the course and treatment of the other. Recent population-based studies have demonstrated that the 2 conditions together increase the risk of stroke, heart failure hospitalization, and all-cause mortality, especially soon after the clinical onset of AF. Guideline-directed pharmacological therapy for HFrEF is important; however, although there are various treatment modalities for AF, there is no clear consensus on how best to treat AF with concomitant HFrEF. This in-depth review discusses the available data for the treatment of AF in the setting of HFrEF, focuses on areas where more investigation is necessary, examines the clinical implications of randomized and observational clinical trials, and presents suggestions for individualized treatment strategies for specific patient groups.

Effects of Long-Acting Loop Diuretics in Heart Failure With Reduced Ejection Fraction Patients With Cardiac Resynchronization Therapy

There have been no reports evaluating the impact of long-acting loop diuretics (LLD) on the outcome of heart failure (HF) and arrhythmia treatment in HF with reduced ejection fraction (HFrEF) patients implanted with a cardiac resynchronization therapy (CRT) device.This was a prospective, single-blind, randomized crossover study. We allocated 21 consecutive CRT implanted patients into 2 groups. The furosemide group received furosemide as a first treatment and azosemide as a second treatment. The azosemide group received this treatment in the reverse order. The first treatment was given to each group for 6 months and the second treatment continued for an additional 6 months. We combined the data of each medication regimen in each group and analyzed it at baseline, 6 months, and 1 year. The primary endpoints were the variation of fluid index and thoracic impedance measured by CRT at 6 months.The baseline characteristics were similar for both groups. The difference in the primary endpoints was not statistically significant between the 2 medication arms (fluid index: -29.6 ± 64.4 versus 16.2 ± 48.2; P = 0.22, thoracic impedance: -0.49 ± 17.8 versus 2.45 ± 12.5; P = 0.56). Likewise, the clinical outcome of HF and the CRT derived parameters in both arms were comparable.HFrEF patients taking LLD after CRT implantation might be comparable to those taking short-acting loop diuretics in the treatment of HF and HF-associated arrhythmias.

Atrial Fibrillation and Hypertension: Mechanistic, Epidemiologic, and Treatment Parallels

Atrial fibrillation (AF) is an increasingly prevalent condition and the most common sustained arrhythmia encountered in ambulatory and hospital practice. Several clinical risk factors for AF include age, sex, valvular heart disease, obesity, sleep apnea, heart failure, and hypertension (HTN). Of all the risk factors, HTN is the most commonly encountered condition in patients with incident AF. Hypertension is associated with a 1.8-fold increase in the risk of developing new-onset AF and a 1.5-fold increase in the risk of progression to permanent AF. Hypertension predisposes to cardiac structural changes that influence the development of AF such as atrial remodeling. The renin angiotensin aldosterone system has been demonstrated to be a common mechanistic link in the pathogenesis of HTN and AF. Importantly, HTN is one of the few modifiable AF risk factors, and guideline-directed management of HTN may reduce the incidence of AF.

A Review of the External Validity of Clinical Trials with Beta-Blockers in Heart Failure

BACKGROUND

Beta-blockers (BBs) are the mainstay prognostic medication for all stages of chronic heart failure (CHF). There are many classes of BBs, each of which has varying levels of evidence to support its efficacy in CHF. However, most CHF patients have one or more comorbid conditions such as diabetes, renal impairment, and/or atrial fibrillation. Patient enrollment to randomized controlled trials (RCTs) often excludes those with certain comorbidities, particularly if the symptoms are severe. Consequently, the extent to which evidence drawn from RCTs is generalizable to CHF patients has not been well described. Clinical guidelines also underrepresent this point by providing generic advice for all patients. The aim of this review is to examine the evidence to support the use of BBs in CHF patients with common comorbid conditions.

METHODS

We searched MEDLINE, PubMed, and the reference lists of reviews for RCTs, post hoc analyses, systematic reviews, and meta-analyses that report on use of BBs in CHF along with patient demographics and comorbidities.

RESULTS

In total, 38 studies from 28 RCTs were identified, which provided data on six BBs against placebo or head to head with another BB agent in ischemic and nonischemic cardiomyopathies. Several studies explored BBs in older patients. Female patients and non-Caucasian race were underrepresented in trials. End points were cardiovascular hospitalization and mortality. Comorbid diabetes, renal impairment, or atrial fibrillation was detailed; however, no reference to disease spectrum or management goals as a focus could be seen in any of the studies. In this sense, enrollment may have limited more severe grades of these comorbidities.

CONCLUSIONS

RCTs provide authoritative information for a spectrum of CHF presentations that support guidelines. RCTs may provide inadequate information for more heterogeneous CHF patient cohorts. Greater Phase IV research may be needed to fill this gap and inform guidelines for a more global patient population.

Is there an association between the prevalence of atrial fibrillation and severity and control of hypertension? The REasons for Geographic And Racial Differences in Stroke study

The association of atrial fibrillation (AF) with the severity and control of hypertension (HTN) remains unclear. We analyzed data from the national biracial cohort of REasons for Geographic And Racial Differences in Stroke study. The AF prevalence ratios were estimated and full multivariable adjustment included demographics, risk factors, medication adherence, HTN duration, and antihypertensive medication classes. Of the 30,018 study participants (8.6% with AF), 4386 had normotension (4.3% with AF), 5916 had prehypertension (4.3 with AF%), 12,294 had controlled HTN (11.2% with AF), 5587 had uncontrolled HTN (8.1% with AF), 547 had controlled apparent treatment-resistant hypertension (aTRH) (19.2% with AF), and 1288 had uncontrolled aTRH (15.5% with AF). Compared with normotension, the AF prevalence ratios for prehypertension, controlled HTN, uncontrolled HTN, controlled aTRH, and uncontrolled aTRH groups in fully adjusted model were 1.01 (95% confidence interval: 0.84, 1.21), 1.42 (1.18, 1.71), 1.37 (1.14, 1.65), 1.17 (0.86, 1.58), and 1.42 (1.10, 1.84), respectively (P < .001). The prevalence of AF was similar among persons with HTN regardless of blood pressure level and antihypertensive treatment resistance.

Blood pressure control versus atrial fibrillation management in stroke prevention

Hypertension is one of the major risk factors for atrial fibrillation which in turn is the most prevalent concomitant condition in hypertensive patients. While both these pathological conditions are independent risk factors for stroke, the association of hypertension and atrial fibrillation increases the incidence of disabling strokes. Moreover, documented or silent atrial fibrillation doubles the rate of cardiovascular death. Lowering blood pressure is strongly recommended, particularly for primary stroke prevention. However, a relatively small percentage of hypertensive patients still achieve the recommended blood pressure goals. The management of atrial fibrillation with respect to stroke prevention is changing. New oral anticoagulants represent a major advancement in long-term anticoagulation therapy in non valvular atrial fibrillation. They have several benefits over warfarin, including improved adherence to the anticoagulation therapy. This is an important issue since non-adherence to stroke prevention medications is a risk factor for first and recurrent strokes.

Effects of RAAS Blockers on Atrial Fibrillation Prophylaxis

Background:

Impact of atrial fibrillation on clinical outcomes is well recognized, and application of renin–angiotensin–aldosterone system (RAAS) blockers for the prevention of atrial fibrillation (AF) is a theoretically appealing concept. However, clinical trials have yielded inconsistent results.

Methods:

A pooled study of 26 randomized controlled trials (RCTs) assessing the efficacy of RAAS blockers on AF prophylaxis was performed.

Results:

A total of 28 reports from 26 randomized controlled trials enrolled 165 387 patients, with an overall 24% reduction in the incidence of AF (odds ratio [OR]: 0.76, 95% confidence interval [CI]: 0.68-0.85], P = .000). Forty-nine percent reduction in the incidence of AF (OR: 0.51, 95% CI: 0.30-0.85, P = .010) in systolic heart failure was observed, whereas no significant effect was observed in patients with diastolic heart failure, postmyocardial infarction, and high cardiovascular disease risk. There was a 19% (OR: 0.81, 95% CI: 0.67-1.00, P = .037) reduction in new-onset and 54% (OR: 0.46, 95% CI: 0.33-0.62, P = .000) reduction in recurrent AF in hypertensive patients with 39% (OR: 0.61, 95% CI: 0.44-0.84, P = .003) risk reduction against calcium blockers and 41% (OR: 0.59, 95% CI: 0.44-0.80, P = .001) risk reduction against β blockers. Angiotensin-receptor blocker appeared marginally superior to angiotensin-converting enzyme inhibitor in primary and secondary prevention.

Conclusion:

This study suggests that RAAS blockade effectively suppresses AF in systolic heart failure, and hypertensives derive greater benefit against new-onset and recurrent AF compared to β blockers, calcium channel blockers, and diuretics.

Clinical and Echocardiographic Factors Associated With New-Onset Atrial Fibrillation in Heart Failure - Subanalysis of the WARCEF Trial

BACKGROUND

Heart failure (HF) patients have a high incidence of new-onset AF. Given the adverse prognostic influence of AF in HF, identifying patients at high risk of developing AF is important.

METHODS AND RESULTS

The incidence and factors associated with new-onset AF were investigated in patients in sinus rhythm with reduced LVEF enrolled in the Warfarin versus Aspirin in Reduced Cardiac Ejection Fraction (WARCEF) trial. Analyses involved clinical factors alone (n=2,219), and clinical plus echocardiographic findings (n=1,125). During 3.5±1.8 years of follow-up, 212 patients (9.6% of total cohort) developed AF. In both samples, new-onset AF was associated with age, male sex, White race, and IHD. Among echocardiographic variables, only LAD predicted AF. On multivariate Cox modeling, age (HR, 1.02; 95% CI: 1.00-1.03, P=0.008), IHD (HR, 1.37; 95% CI: 1.02-1.84, P=0.036) and LAD (HR, 1.48; 95% CI: 1.15-1.91, P=0.003) remained associated with AF onset. Patients with IHD, LAD>4.5 cm and age>50 years had a 2.5-fold higher risk of AF than patients without any of these characteristics (HR, 2.52; 95% CI: 1.72-3.69, P<0.0001).

CONCLUSIONS

Age, IHD and LAD independently predict new-onset AF in HF patients in sinus rhythm, at younger age and smaller LAD than generally believed. This information may be useful to risk-stratify HF patients for AF development, allowing close monitoring and possibly early detection. (Circ J 2016; 80: 619-626).

Should β-blockers be used in patients with heart failure and atrial fibrillation?

PURPOSE

There is overwhelming evidence that β-blockers reduce cardiovascular hospitalizations and mortality in patients with heart failure and a reduced left ventricular ejection fraction provide they are in sinus rhythm. However, a recent meta-analysis of individual patient data provides compelling evidence that β-blockers are not effective in patients with heart failure and atrial fibrillation, although neither did they increase risk. The purpose of this article is to review the evidence, seek possible explanations for this observation, and make recommendations based on the limited evidence available.

METHODS

Review and critical analysis of recent publications and meta-analyses on the use of β-blockers and other heart rate-slowing medicines in heart failure.

FINDINGS

The reasons for the lack of effect of β-blockers in patients with heart failure are uncertain. There is a substantial body of evidence to suggest that patients with heart failure and atrial fibrillation who have less stringent ventricular rate control have a better outcome. The most plausible explanation for these findings, in our view, is that β-blockers exert similar benefits through similar mechanisms regardless of intrinsic heart rhythm but that the benefits of β-blockers are neutralized in patients with atrial fibrillation due to the induction of pauses that may impair cardiac function leading to worsening heart failure or cause arrhythmias resulting in death.

IMPLICATIONS

Smaller doses of β-blockers and other rate lowering agents to achieve a resting clinic heart rate in the range of 75-89beats/min might improve outcome. Preventing pauses by pacing or pulmonary vein ablation of atrial fibrillation are strategies that should be researched.