Rhythm vs. rate control of atrial fibrillation meta-analysed by number needed to treat

The Increasing Role of Rhythm Control in Patients With Atrial Fibrillation: JACC State-of-the-Art Review

The considerable mortality and morbidity associated with atrial fibrillation (AF) pose a substantial burden on patients and health care services. Although the management of AF historically focused on decreasing AF recurrence, it evolved over time in favor of rate control. Recently, more emphasis has been placed on reducing adverse cardiovascular outcomes using rhythm control, generally by using safe and effective rhythm-control therapies (typically antiarrhythmic drugs and/or AF ablation). Evidence increasingly supports early rhythm control in patients with AF that has not become long-standing, but current clinical practice and guidelines do not yet fully reflect this change. Early rhythm control may effectively reduce irreversible atrial remodeling and prevent AF-related deaths, heart failure, and strokes in high-risk patients. It has the potential to halt progression and potentially save patients from years of symptomatic AF; therefore, it should be offered more widely.

Rate and Rhythm Control Treatment in the Elderly and Very Elderly Patients With Atrial Fibrillation: An Observational Cohort Study of 1497 Patients

Stroke prevention and rate or rhythm control are crucial in the management of atrial fibrillation (AF). There is recent evidence for benefit of early rhythm control, yet rate control is the first choice in elderly patients. However, the efficacy and safety of rate and rhythm control in the elderly population remains largely unexplored. Therefore, we analyzed electronic health record data and investigated prescribing patterns and mortality of both strategies in elderly patients with AF. Data from patients with AF who were aged ≥75 years, used a pharmacological rate or rhythm control strategy, and visited Cardiology Centers of the Netherlands between 2007 and 2018 were extracted. Of the 1497 patients (54% female), 316 (21%) were prescribed rhythm control and 1181 (79%) rate control. Patients aged >85 years (OR: 2.28; 95% CI: 1.51-3.44, P< 0.001) and those with permanent AF (OR: 2.71; 95% CI: 1.67-4.41, P< 0.001) were more likely to receive rate control, whereas those with paroxysmal AF were less likely to receive rate control (OR: 0.42; 95% CI: 0.32-0.56, P< 0.001). After correction for relevant confounders, the mortality risk for patients using rhythm control and patients using rate control was similar (HR: 0.89; 95% CI: 0.70-1.12, P = 0.31). A more liberal approach towards prescribing a rhythm control strategy to the elderly patients with AF may be warranted and seems safe. Our data underscore the need for prospective studies to provide definite answers on efficacy and safety of rhythm control in elderly patients with AF.

Computational models of atrial fibrillation: achievements, challenges, and perspectives for improving clinical care

Despite significant advances in its detection, understanding and management, atrial fibrillation (AF) remains a highly prevalent cardiac arrhythmia with a major impact on morbidity and mortality of millions of patients. AF results from complex, dynamic interactions between risk factors and comorbidities that induce diverse atrial remodelling processes. Atrial remodelling increases AF vulnerability and persistence, while promoting disease progression. The variability in presentation and wide range of mechanisms involved in initiation, maintenance and progression of AF, as well as its associated adverse outcomes, make the early identification of causal factors modifiable with therapeutic interventions challenging, likely contributing to suboptimal efficacy of current AF management. Computational modelling facilitates the multilevel integration of multiple datasets and offers new opportunities for mechanistic understanding, risk prediction and personalized therapy. Mathematical simulations of cardiac electrophysiology have been around for 60 years and are being increasingly used to improve our understanding of AF mechanisms and guide AF therapy. This narrative review focuses on the emerging and future applications of computational modelling in AF management. We summarize clinical challenges that may benefit from computational modelling, provide an overview of the different in silico approaches that are available together with their notable achievements, and discuss the major limitations that hinder the routine clinical application of these approaches. Finally, future perspectives are addressed. With the rapid progress in electronic technologies including computing, clinical applications of computational modelling are advancing rapidly. We expect that their application will progressively increase in prominence, especially if their added value can be demonstrated in clinical trials.

Treatment timing and the effects of rhythm control strategy in patients with atrial fibrillation: nationwide cohort study

OBJECTIVE

To investigate whether the results of a rhythm control strategy differ according to the duration between diagnosis of atrial fibrillation and treatment initiation.

DESIGN

Longitudinal observational cohort study.

SETTING

Population based cohort from the Korean National Health Insurance Service database.

PARTICIPANTS

22 635 adults with atrial fibrillation and cardiovascular conditions, newly treated with rhythm control (antiarrhythmic drugs or ablation) or rate control strategies between 28 July 2011 and 31 December 2015.

MAIN OUTCOME MEASURE

A composite outcome of death from cardiovascular causes, ischaemic stroke, admission to hospital for heart failure, or acute myocardial infarction.

RESULTS

Of the study population, 12 200 (53.9%) were male, the median age was 70, and the median follow-up duration was 2.1 years. Among patients with early treatment for atrial fibrillation (initiated within one year since diagnosis), compared with rate control, rhythm control was associated with a lower risk of the primary composite outcome (weighted incidence rate per 100 person years 7.42 in rhythm control v 9.25 in rate control; hazard ratio 0.81, 95% confidence interval 0.71 to 0.93; P=0.002). No difference in the risk of the primary composite outcome was found between rhythm and rate control (weighted incidence rate per 100 person years 8.67 in rhythm control v 8.99 in rate control; 0.97, 0.78 to 1.20; P=0.76) in patients with late treatment for atrial fibrillation (initiated after one year since diagnosis). No significant differences in safety outcomes were found between the rhythm and rate control strategies across different treatment timings. Earlier initiation of treatment was linearly associated with more favourable cardiovascular outcomes for rhythm control compared with rate control.

CONCLUSIONS

Early initiation of rhythm control treatment was associated with a lower risk of adverse cardiovascular outcomes than rate control treatment in patients with recently diagnosed atrial fibrillation. This association was not found in patients who had had atrial fibrillation for more than one year.

The effects of rhythm control strategies versus rate control strategies for atrial fibrillation and atrial flutter: A systematic review with meta-analysis and Trial Sequential Analysis

Background

Atrial fibrillation and atrial flutter may be managed by either a rhythm control strategy or a rate control strategy but the evidence on the clinical effects of these two intervention strategies is unclear. Our objective was to assess the beneficial and harmful effects of rhythm control strategies versus rate control strategies for atrial fibrillation and atrial flutter.

Methods

We searched CENTRAL, MEDLINE, Embase, LILACS, Web of Science, BIOSIS, Google Scholar, clinicaltrials.gov, TRIP, EU-CTR, Chi-CTR, and ICTRP for eligible trials comparing any rhythm control strategy with any rate control strategy in patients with atrial fibrillation or atrial flutter published before November 2016. Our primary outcomes were all-cause mortality, serious adverse events, and quality of life. Our secondary outcomes were stroke and ejection fraction. We performed both random-effects and fixed-effect meta-analysis and chose the most conservative result as our primary result. We used Trial Sequential Analysis (TSA) to control for random errors. Statistical heterogeneity was assessed by visual inspection of forest plots and by calculating inconsistency (I²) for traditional meta-analyses and diversity (D²) for TSA. Sensitivity analyses and subgroup analyses were conducted to explore the reasons for substantial statistical heterogeneity. We assessed the risk of publication bias in meta-analyses consisting of 10 trials or more with tests for funnel plot asymmetry. We used GRADE to assess the quality of the body of evidence.

Results

25 randomized clinical trials (n = 9354 participants) were included, all of which were at high risk of bias. Meta-analysis showed that rhythm control strategies versus rate control strategies significantly increased the risk of a serious adverse event (risk ratio (RR), 1.10; 95% confidence interval (CI), 1.02 to 1.18; P = 0.02; I² = 12% (95% CI 0.00 to 0.32); 21 trials), but TSA did not confirm this result (TSA-adjusted CI 0.99 to 1.22). The increased risk of a serious adverse event did not seem to be caused by any single component of the composite outcome. Meta-analysis showed that rhythm control strategies versus rate control strategies were associated with better SF-36 physical component score (mean difference (MD), 6.93 points; 95% CI, 2.25 to 11.61; P = 0.004; I² = 95% (95% CI 0.94 to 0.96); 8 trials) and ejection fraction (MD, 4.20%; 95% CI, 0.54 to 7.87; P = 0.02; I² = 79% (95% CI 0.69 to 0.85); 7 trials), but TSA did not confirm these results. Both meta-analysis and TSA showed no significant differences on all-cause mortality, SF-36 mental component score, Minnesota Living with Heart Failure Questionnaire, and stroke.

Conclusions

Rhythm control strategies compared with rate control strategies seem to significantly increase the risk of a serious adverse event in patients with atrial fibrillation. Based on current evidence, it seems that most patients with atrial fibrillation should be treated with a rate control strategy unless there are specific reasons (e.g., patients with unbearable symptoms due to atrial fibrillation or patients who are hemodynamically unstable due to atrial fibrillation) justifying a rhythm control strategy. More randomized trials at low risk of bias and low risk of random errors are needed.

Trial registration

PROSPERO CRD42016051433

Recent Advances in the Pharmacological Management of Atrial Fibrillation

Atrial fibrillation (AF) is a highly prevalent cardiac arrhythmia that leads to hospitalizations for complications and adverse events each year. Despite significant improvement in our therapeutic approaches in the past decade, management of AF remains a difficult task. Novel therapies have failed to terminate AF and prevent its recurrence, and patients with AF continue to have thromboembolic complications. With the increasingly aging population and associated conditions, the prevalence of AF is expected to progressively increase, becoming a public health problem. Most patients with AF have multiple comorbidities and are of advanced age, making long-term anticoagulation challenging. This article provides an overview of the current pharmacological therapies for the management of AF, with particular emphasis on the emerging agents.

Practical Issues to Prevent Stroke Associated with Non-valvular Atrial Fibrillation

Stroke associated with non-valvular atrial fibrillation (NVAF) is one of the most important subtypes of ischemic stroke, and its importance is becoming even more apparent in an aging population. To assess the risk of stroke associated with NVAF, the CHADS2 and CHA2DS2-VASc scores are mainly used. Such scores can be used to predict the recurrence and prognosis of ischemic stroke. In addition, new oral anticoagulants (NOACs) and devices are being evaluated in the prevention of stroke associated with NVAF in addition to treatment with the conventional oral anticoagulant, warfarin. Since clinical experience with NOACs is not globally sufficient, a cautious approach is needed.

Current Evidence and Recommendations for Rate Control in Atrial Fibrillation

Atrial fibrillation (AF) is the most common cardiac arrhythmia encountered in clinical practice, which is associated with substantial risk of stroke and thromboembolism. As an arrhythmia that is particularly common in the elderly, it is an important contributor towards morbidity and mortality. Ventricular rate control has been a preferred and therapeutically convenient treatment strategy for the management of AF. Recent research in the field of rhythm control has led to the advent of newer antiarrhythmic drugs and catheter ablation techniques as newer therapeutic options. Currently available antiarrhythmic drugs still remain limited by their suboptimal efficacy and significant adverse effects. Catheter ablation as a newer modality to achieve sinus rhythm (SR) continues to evolve, but data on long-term outcomes on its efficacy and mortality outcomes are not yet available. Despite these current developments, rate control continues to be the front-line treatment strategy, especially in older and minimally symptomatic patients who might not tolerate the antiarrhythmic drug treatment. This review article discusses the current evidence and recommendations for ventricular rate control in the management of AF. We also highlight the considerations for rhythm control strategy in the management of patients of AF.

Review of epidemiology and management of atrial fibrillation in developing countries

BACKGROUND

Atrial fibrillation (AF) is the commonest sustained cardiac arrhythmia. In developing countries, AF is a growing public health problem with the epidemiologic transition from communicable to non-communicable diseases. However, relatively little is known about AF in the developing world. The aim of this review is to examine in developing countries the prevalence, associated medical conditions and management of AF.

METHODS

A literature search was conducted via MEDLINE and EMBASE (1990-2012).

RESULTS

Seventy studies were included in the review. The prevalence of AF in the general population ranged from 0.03% to 1.25%, while the prevalence of AF in hospital-based studies varied from 0.7% to 55.7%. Prevalence of AF in Africa was lower than in other regions. The most common conditions associated with AF were hypertension (10.3%-71.9%) and valvular heart disease (5.6%-66.3%). The prevalence of stroke in patients with AF ranged from 6.7% to 27%. The utilization of anticoagulants was highly variable (2.7%-72.7%). Approximately half of the patients with AF using warfarin had therapeutic International Normalized Ratios (INR). There was a high prevalence of use of rate control therapies (55.3%-87.3%).

CONCLUSIONS

The limited studies available suggest that in the developing world there is a significant prevalence of AF, which is predominantly associated with hypertension and valvular heart disease, and carries a risk of stroke. Highly variable use of anticoagulants may be related to different health care and socioeconomic settings. More studies are needed to improve understanding of the epidemiology and management of AF in developing countries.

Rhythm versus rate control therapy and subsequent stroke or transient ischemic attack in patients with atrial fibrillation

BACKGROUND

Stroke is a debilitating condition with an increased risk in patients with atrial fibrillation. Although data from clinical trials suggest that both rate and rhythm control are acceptable approaches with comparable rates of mortality in the short term, it is unclear whether stroke rates differ between patients who filled prescriptions for rhythm or rate control therapy.

METHODS AND RESULTS

We conducted a population-based observational study of Quebec patients ≥65 years with a diagnosis of atrial fibrillation during the period 1999 to 2007 with the use of linked administrative data from hospital discharge and prescription drug claims databases. We compared rates of stroke or transient ischemic attack (TIA) among patients using rhythm (class Ia, Ic, and III antiarrhythmics), versus rate control (β-blockers, calcium channel blockers, and digoxin) treatment strategies (either current or new users). The cohort consisted of 16 325 patients who filled a prescription for rhythm control therapy (with or without rate control therapy) and 41 193 patients who filled a prescription for rate control therapy, with a mean follow-up of 2.8 years (maximum 8.2 years). A lower proportion of patients on rhythm control therapy than on rate control therapy had a CHADS(2) (congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, and previous stroke or TIA) score of ≥2 (58.1% versus 67.0%, P<0.001). Treatment with any antithrombotic drug was comparable in the 2 groups (76.8% in rhythm control versus 77.8% in rate control group). Crude stroke/TIA incidence rate was lower in patients treated with rhythm control in comparison with rate control therapy (1.74 versus 2.49, per 100 person-years, P<0.001). This association was more marked in patients in the moderate- and high-risk groups for stroke according to the CHADS(2) risk score. In multivariable Cox regression analysis, rhythm control therapy was associated with a lower risk of stroke/TIA in comparison with rate control therapy (adjusted hazard ratio, 0.80; 95% confidence interval, 0.74, 0.87). The lower stroke/TIA rate was confirmed in a propensity score-matched cohort.

CONCLUSIONS

In comparison with rate control therapy, the use of rhythm control therapy was associated with lower rates of stroke/TIA among patients with atrial fibrillation, in particular, among those with moderate and high risk of stroke.

Real-life global survey evaluating patients with atrial fibrillation (REALISE-AF): results of an international observational registry

Despite being one of the most studied arrhythmias, there is paucity of information regarding atrial fibrillation (AF) control in the general population and the treatment strategies utilized by healthcare providers. REALISE-AF is an ongoing international registry investigating the management of AF and its control in nonhospitalized subjects. The registry has enrolled patients in 26 countries worldwide with the primary aim to determine the control of AF. This article presents a review of the initial results from the REALISE-AF registry and compares it to major practice-changing clinical trials conducted in the past. It also gives an overview of the current management strategies, recent updates in treatment and what further developments portend in the future.

Atrial fibrillation (chronic)

INTRODUCTION

Atrial fibrillation is a supraventricular tachyarrhythmia characterised by the presence of fast and uncoordinated atrial activation leading to reduced atrial mechanical function. Risk factors for atrial fibrillation include increasing age, male sex, co-existing cardiac and thyroid disease, pyrexial illness, electrolyte imbalance, cancer, and co-existing infection.

METHODS AND OUTCOMES

We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of oral medical treatments to control heart rate in people with chronic (defined as longer than 1 week for this review) non-valvular atrial fibrillation? What is the effect of different treatment strategies (rate versus rhythm) for people with persistent non-valvular atrial fibrillation? We searched: Medline, Embase, The Cochrane Library, and other important databases up to June 2011 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).

RESULTS

We found 23 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.

CONCLUSIONS

In this systematic review we present information relating to the effectiveness and safety of the following interventions: beta-blockers (with or without digoxin), calcium channel blockers (with or without digoxin), calcium channel blockers (rate-limiting), digoxin, and rate versus rhythm control strategies.

Update on anti-coagulation in atrial fibrillation

Atrial fibrillation (AF), the most common clinically relevant arrhythmia, affects 2.2 million individuals in the USA and 4.5 million in Europe, resulting in significant morbidity and mortality. Pharmacotherapy aimed at controlling both heart rate and rhythm is employed to relieve AF symptoms, though debate continues about which approach is preferable. AF prevalence rises with age from 0.4% to 1% in the general population to 11% in those aged >70 years. AF is associated with a pro-thrombotic state and other comorbidities; age, hypertension, heart failure and diabetes mellitus all play a key role in AF pathogenesis. Anti-coagulation is essential for stroke prevention in patients with AF and is recommended for patients with one or more risk factors for stroke. Used within the recommended therapeutic range, warfarin and other vitamin K antagonists decrease the incidence of stroke and mortality in AF patients. Warfarin remains under-used, however, because of the perceived high risk of haemorrhage, narrow therapeutic window and need for regular monitoring. Several novel anti-coagulants show promise in AF-related stroke prevention. In particular, the novel, oral, direct thrombin inhibitor, dabigatran etexilate, recently licensed by the US Food and Drug Administration (FDA) and Health Canada has shown improved efficacy and safety compared with warfarin for stroke prevention in AF, and has the potential to replace warfarin in this indication. The increasing number of new therapeutic options, including improved anti-arrhythmic agents, novel anti-coagulants and more accessible ablation techniques, are likely to deliver better care for AF patients in the near future.

Prevention of atrial fibrillation: report from a national heart, lung, and blood institute workshop

The National Heart, Lung, and Blood Institute convened an expert panel April 28 to 29, 2008, to identify gaps and recommend research strategies to prevent atrial fibrillation (AF). The panel reviewed the existing basic scientific, epidemiological, and clinical literature about AF and identified opportunities to advance AF prevention research. After discussion, the panel proposed the following recommendations: (1) enhance understanding of the epidemiology of AF in the population by systematically and longitudinally investigating symptomatic and asymptomatic AF in cohort studies; (2) improve detection of AF by evaluating the ability of existing and emerging methods and technologies to detect AF; (3) improve noninvasive modalities for identifying key components of cardiovascular remodeling that promote AF, including genetic, fibrotic, autonomic, structural, and electrical remodeling markers; (4) develop additional animal models reflective of the pathophysiology of human AF; (5) conduct secondary analyses of already-completed clinical trials to enhance knowledge of potentially effective methods to prevent AF and routinely include AF as an outcome in ongoing and future cardiovascular studies; and (6) conduct clinical studies focused on secondary prevention of AF recurrence, which would inform future primary prevention investigations.

Atrial fibrillation (chronic)

INTRODUCTION

Atrial fibrillation is a supraventricular tachyarrhythmia, which is characterised by the presence of fast and uncoordinated atrial activation leading to reduced atrial mechanical function. Risk factors for atrial fibrillation include increasing age, coexisting cardiac and thyroid disease, pyrexial illness, electrolyte imbalance, cancer, and coexisting infection.

METHODS AND OUTCOMES

We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of oral medical treatments to control heart rate in people with chronic (defined as longer than 1 week for this review) non-valvular atrial fibrillation? What is the effect of different treatment strategies (rate vs. rhythm) for people with persistent non-valvular atrial fibrillation? We searched: Medline, Embase, The Cochrane Library and other important databases up to August 2007 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).

RESULTS

We found 18 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.

CONCLUSIONS

In this systematic review we present information relating to the effectiveness and safety of the following interventions: beta-blockers (with or without digoxin), calcium channel blockers (with or without digoxin), calcium channel blockers (rate limiting), digoxin, and rate versus rhythm control strategies.

Management of atrial fibrillation

Atrial fibrillation is the most common sustained cardiac rhythm disorder, and confers a substantial mortality and morbidity from stroke, thromboembolism, heart failure, and impaired quality of life. With the increasingly elderly population in the developed world, as well as improvements in the management of myocardial infarction and heart failure, the prevalence of atrial fibrillation is increasing, resulting in a major public-health problem. This Review aims to provide an overview on the modern management of atrial fibrillation, with particular emphasis on pharmacological and non-pharmacological approaches. Irrespective of a rate-control or rhythm-control strategy, stroke prevention with appropriate thromboprophylaxis still remains central to the management of this common arrhythmia. Electrophysiological approaches could hold some promise for a curative approach in atrial fibrillation.