Rate control vs rhythm control in patients with nonvalvular persistent atrial fibrillation: the results of the Polish How to Treat Chronic Atrial Fibrillation (HOT CAFE) Study

Optimizing the management of atrial fibrillation: focus on current guidelines and the impact of new agents on future recommendations

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia encountered in everyday clinical practice. It affects ~2.3 million individuals in the United States, and the prevalence is expected to increase ~2.5-fold over the next 40 years. Atrial fibrillation accounts for more than 2 million hospitalizations each year and contributes to nearly 67 000 deaths. Our understanding of the pathophysiology of AF has increased dramatically over the past few decades. Recent treatment guidelines have heightened our awareness of the challenges involved in the treatment of AF and provided useful recommendations for its diagnosis and management. Because AF is usually associated with multiple comorbid conditions, greater emphasis must be placed on individualizing treatment. This review focuses on current treatment guidelines for patients with AF, assessing the benefits and shortcomings of current pharmacologic options and discussing new agents and trials that may provide better opportunities to improve and individualize patient management.

Practice patterns among United States cardiologists for managing adults with atrial fibrillation (from the AFFECTS Registry)

The Atrial Fibrillation: Focus on Effective Clinical Treatment Strategies (AFFECTS) Registry was designed to examine atrial fibrillation (AF) treatment by United States cardiologists in the context of the American College of Cardiology, American Heart Association, and European Society of Cardiology guidelines after recent landmark clinical trials. Most patients in AFFECTS had AF without clinically significant structural heart disease or only uncomplicated hypertension. Among the all-enrolled population (n = 1,461), initial treatment strategies assigned were rhythm control in 64% and rate control in 36%. Among patients with either paroxysmal (n = 1,165) or persistent (n = 273) AF, 67% and 55%, respectively, were assigned rhythm control. The trend to assign rhythm control as the initial treatment goal decreased with age. In the rhythm-control group, most patients (74%) also received a rate-control agent during the registry, while 25% of those assigned to rate control received antiarrhythmic drugs. Most first prescriptions of antiarrhythmic drugs were for first-line therapy compliant with 2001 (76%) and 2006 (86%) guidelines. Most second prescriptions were for first-line therapies as well. Rates of serious adverse events were low. In conclusion, data from this study provide insight into community treatment patterns in patients with AF, most without clinically significant structural heart disease or with only uncomplicated hypertension.

Atrial fibrillation in congestive heart failure

Atrial fibrillation and congestive heart failure are morbid conditions that have common risk factors and frequently coexist. Each condition predisposes to the other, and the concomitant presence of the two identifies individuals at increased risk for mortality. Recent data have emerged that help elucidate the complex genetic and nongenetic pathophysiological mechanisms that contribute to the development of atrial fibrillation in individuals with congestive heart failure. Clinical trial results offer insights into the noninvasive prevention and management of these conditions, although newer technologies, such as catheter ablation for atrial fibrillation, have yet to be studied extensively in patients with congestive heart failure.

Atrial fibrillation in heart failure: a comprehensive review

Chronic heart failure and atrial fibrillation are 2 major disorders that are closely linked. Their coexistence is associated with adverse prognosis. Both share several common predisposing conditions, but their interaction involves complex ultrastructural, electrophysiologic, and neurohormonal processes that go beyond mere sharing of mutual risk factors. Rate control approach remains the standard therapy for atrial fibrillation in heart failure because current strategies at rhythm control have so far failed to positively impact mortality and morbidity. This is largely because of the shortcomings of current pharmacologic anti-arrhythmic agents. Surgical and catheter-based therapies are promising, but long-term data are lacking. The role of non-anti-arrhythmic therapeutic agents also is being explored. Further progress toward improved understanding the complex relationship between atrial fibrillation and heart failure should improve management strategies.

Flecainide for cardioversion in patients at elevated cardiovascular risk and persistent atrial fibrillation: a prospective observational study

BACKGROUND

Flecainide is used as a pill-in-the-pocket treatment for pharmacological cardioversion in patients without structural heart disease and atrial fibrillation (AF). In patients with structural heart disease and elevated cardiovascular risk, flecainide is believed to be harmful. Therefore, data about safety and effectiveness of single-dose flecainide for cardioversion in patients at elevated cardiovascular risk are lacking.

OBJECTIVES

One-hundred and six consecutive patients with recent onset AF and known structural heart disease and/or elevated PROCAM-score did receive oral flecainide 300 mg for cardioversion.

METHODS

The effectiveness, safety and influencing factors of flecainide for cardioversion in high-risk patients were prospectively assessed.

RESULTS

In 43 of 106 patients (40.6%), sinus rhythm could be restored within 192.4 +/- 10.7 min by flecainide. The PROCAM-score was 41.5 +/- 0.56 in patients with successful cardioversion compared to 45.7 +/- 0.74 in patients without successful cardioversion (P < 0.001). ACE-inhibitor co-medication was associated with a significantly lower rate of conversion by flecainide (HR 2.3, 95% CI, 1.12-4.26, P < 0.01). In 58 of 63 patients in whom cardioversion by flecainide was not effective, electrical cardioversion was performed which was successful in 47 patients. Life-threatening arrhythmias did not occur in any patient. The most common side effect was sinus-bradycardia and transient sinus arrest (2-4 s) immediately after conversion.

CONCLUSIONS

When monitored properly, flecainide is safe and useful for cardioversion in patients at elevated cardiovascular risk.

Atrial fibrillation in congestive heart failure

Atrial fibrillation (AF) and heart failure (HF) are common and interrelated conditions, each promoting the other, and both associated with increased mortality. HF leads to structural and electrical atrial remodeling, thus creating the basis for the development and perpetuation of AF; and AF may lead to hemodynamic deterioration and the development of tachycardia-mediated cardiomyopathy. Stroke prevention by antithrombotic therapy is crucial in patients with AF and HF. Of the 2 principal therapeutic strategies to treat AF, rate control and rhythm control, neither has been shown to be superior to the other in terms of survival, despite better survival in patients with sinus rhythm compared with those in AF. Antiarrhythmic drug toxicity and poor efficacy are concerns. Catheter ablation of AF can establish sinus rhythm without the risks of antiarrhythmic drug therapy, but has important procedural risks, and data from randomized trials showing a survival benefit of this treatment strategy are still lacking. In intractable cases, ablation of the atrioventricular junction and placement of a permanent pacemaker is a treatment alternative; and biventricular pacing may prevent or reduce the negative consequences of chronic right ventricular pacing.

[The place of antiarrythmic drugs and rythm control in the treatment of atrial fibrillation]

Atrial fibrillation is the most commonly encountered arrhythmia in daily practice. Its incidence increases with age. It has been established that in this pathology there is self-aggravation with adverse electrical, functional, and structural remodeling of the atrial tissue. This remodeling can increase morbidity and mortality associated with atrial fibrillation. It has become increasingly clear that early checking of cardiac rhythm can stop this harmful remodeling. Several antiarrhythmia treatments have been demonstrated to be effective in cardioversion of arrhythmia and maintenance of the sinus rhythm. The therapeutic strategy depends on the degree of structural damage. Therapeutic trials and treatment selection take into account any possible cardiac side effects of the medications. The class IC antiarrhythmic agents are medications whose safety and efficacy have been demonstrated in patients with no underlying heart conditions. This article explores the advantages of maintaining the sinus rhythm using arrhythmics and the practical strategy of the pharmacological approach.

A practical approach to the management of patients with atrial fibrillation

Atrial fibrillation is the most commonly encountered clinical arrhythmia and continues to grow in incidence. Current management involves highly individualised therapies based on underlying concomitant disease processes and symptoms. Moreover, there are numerous therapeutic permutations involving anticoagulation, rate-limitation and antiarrhythmic strategies. This review serves to update the clinician with a practical approach to each patient population and on current advances in management.

Can we improve outcomes in AF patients by early therapy?

Atrial fibrillation affects at least 1% of the population and causes marked society-wide morbidity and mortality. Current management of atrial fibrillation including antithrombotic therapy and management of concomitant conditions in all patients, rate control therapy in most patients, and rhythm control therapy in patients with severe atrial fibrillation-related symptoms can alleviate atrial fibrillation-related symptoms but can neither effectively prevent recurrent atrial fibrillation nor suppress atrial fibrillation-related complications. Hence, there is a need for better therapy of atrial fibrillation. The etiology of atrial fibrillation is complex. Most of the causes of atrial fibrillation which are known at present perpetuate themselves in vicious circles, and presence of the arrhythmia by itself causes marked damage of atrial myocardium. These pathophysiological insights suggest that early diagnosis and comprehensive therapy of atrial fibrillation, including adequate therapy of all atrial fibrillation-causing conditions, rate control, and rhythm control therapy, could help to prevent progression of atrial fibrillation and reduce atrial fibrillation-related complications. Such a therapy should make use of safe and effective therapeutic modalities, some of which have become available recently or will become available in the near future. The hypothesis that early diagnosis and early, comprehensive therapy of atrial fibrillation can improve outcomes requires formal testing in controlled trials.

Atrial fibrillation: mechanistic insights and treatment options

Atrial fibrillation (AF) remains the most common clinically encountered arrhythmia. Unlike supraventricular arrhythmias that use a defined mechanism, AF involves a wide spectrum of arrhythmias from lone AF to paroxysmal to chronic AF. AF is an arrhythmia that may develop in several ways. Mechanical remodeling manifests as decreased atrial contractility and increased atrial compliance which leads to a stretch of the atrial myocardium. Atrial remodeling may also increase in atrial fibrosis which can slow conduction velocity and can shorten the refractory period in atria with long-standing AF. It is still unclear whether initiation of AF activates direct inflammatory effects or whether the presence of a pre-existing systemic inflammatory state promotes further persistence of AF. Currently, the patient population undergoing AF ablation has greatly expanded. Patients are older and have larger left atrial size and are more likely to have persistent/permanent AF. It is likely that AF comprises a spectrum of disease with no single mechanism adequate enough to comprehensively explain AF and its variability. The management of patients with AF involves elements of anticoagulation, rate control and rhythm control and such treatment strategies are not necessarily mutually exclusive of each other.

Cardioversion for atrial fibrillation: treatment options and advances

Atrial fibrillation (AF) is associated with significant morbidity and mortality. There are two basic approaches to managing AF: slowing the ventricular rate, while allowing the arrhythmia to continue (the rate-control approach), and restoring and maintaining sinus rhythm (the rhythm-control approach) with antiarrhythmic drugs (AADs) and/or ablation, electrical cardioversion (CV), if needed, or both. Strategy trials comparing rate and rhythm control have found no survival advantage of one approach over the other, but other considerations, such as symptom reduction, often necessitate pursuit of rhythm control. Electrical, or direct current, CV is a widely used and effective method for termination of nonparoxysmal AF, although its success can be affected by patient- and technique-related variables. Pharmacological CV options also exist and are preferable in specific circumstances. Both pharmacological and electrical CV are associated with the risk of proarrhythmia. Many AADs are under development for both CV and maintenance of sinus rhythm. Some are atrioselective, such as vernakalant, and target ion channels in the atria, with little or no effects in the ventricle. Vernakalant, currently under Food and Drug Administration review, appears to offer a safer profile than current CV agents and is likely to expand the role of pharmacological CV. Other new AADs that provide increased efficacy or safety while maintaining normal sinus rhythm may also be better than current drugs; if so, rate-rhythm comparisons will differ from those of previous studies. In conclusion, further trials should clarify the long-term safety profiles of new atrioselective agents and other investigational drugs and define their role in the treatment of AF.

Dronedarone

Amiodarone is the most effective antiarrhythmic drug for maintaining sinus rhythm for patients with atrial fibrillation. Extra-cardiac side effects have been a limiting factor, especially during chronic use, and may offset its benefits. Dronedarone is a noniodinated benzofuran derivative of amiodarone that has been developed for the treatment of atrial fibrillation and atrial flutter. Similar to amiodarone, dronedarone is a potent blocker of multiple ion currents, including the rapidly activating delayed-rectifier potassium current, the slowly activating delayed-rectifier potassium current, the inward rectifier potassium current, the acetylcholine activated potassium current, peak sodium current, and L-type calcium current, and exhibits antiadrenergic effects. It has been studied for maintenance of sinus rhythm and control of ventricular response during episodes of atrial fibrillation. Dronedarone reduces mortality and morbidity in patients with high-risk atrial fibrillation, but may be unsafe in those with severe heart failure. This article will review evidence of safety and effectiveness of dronedarone in patients with atrial fibrillation.

I(Kur)/Kv1.5 channel blockers for the treatment of atrial fibrillation

Atrial fibrillation (AF) is the most common sustained arrhythmia. Anti-arrhythmic drugs remain the mainstay of therapy, but the available class I and III anti-arrhythmic drugs are only moderately effective in long-term restoring/maintaining sinus rhythm (SR) and can produce potentially fatal ventricular pro-arrhythmia. In an attempt to identify safer and more effective anti-arrhythmic drugs, drug discovery efforts have focused on 'atrial selective drugs' that target cardiac ion channel(s) that are exclusively or predominantly expressed in the atria. The ultra-rapid activating delayed rectifier K(+) current (I(Kur)), carried by Kv1.5 channels, is a major repolarizing current in human atria, but seems to play no role in the ventricle. This finding offers the possibility of developing selective I(Kur) blockers to restore and maintain SR without a risk of ventricular pro-arrhythmia. Several I(Kur) blockers are now being developed but clinical data are still limited, so the precise role of these agents in the treatment of AF remains to be defined. In this review we analyze the possible advantages and disadvantages of the developmental I(Kur) blockers as they represent the first step for the development of potential atrial selective drugs for a more effective and safer treatment and prevention of AF.

Contemporary management of atrial fibrillation: update on anticoagulation and invasive management strategies

Atrial fibrillation (AF) is the most common arrhythmia encountered in clinical practice. Its increasing prevalence, particularly among the elderly, renders it one of the most serious current medical epidemics. Several management questions confront the clinician treating a patient with AF: Should the condition be treated? Is the patient at risk of death or serious morbidity as a result of this diagnosis? If treatment is necessary, is rate control or rhythm control superior? Which patients need anticoagulation therapy, and for how long? This review of articles obtained by a search of the PubMed and MEDLINE databases presents the available evidence that can guide the clinician in answering these questions. After discussing the merits of available therapy, including medications aimed at controlling rate, rhythm, or both, we focus on the present status of ablative therapy for AF. Catheter ablation, particularly targeting the pulmonary veins, is being increasingly performed, although the precise indications for this approach and its effectiveness and safety are being actively investigated. We briefly discuss other invasive options that are less frequently used, such as pacemakers, defibrillators, left atrial appendage closure devices, and the surgical maze procedure.

Atrial fibrillation in congestive heart failure: current management

Atrial fibrillation (AF) and congestive heart failure are common conditions and each predisposes to the development of the other. Basic research using animal models of the two conditions continues to yield insights that may improve therapies. The role of medical therapies aimed at the underlying structural changes in AF continues to be a subject of ongoing studies. Cardiac resynchronization therapy is effective in appropriately selected patients with both sinus rhythm and AF. Catheter ablation is emerging as a potential alternative to antiarrhythmic drug therapy, but large randomized trials will be needed to assess its role.

Atrial fibrillation and congestive heart failure

PURPOSE OF REVIEW

The present review will examine the prognostic importance of atrial fibrillation and heart failure, explore the different therapeutic options for treating atrial fibrillation and present the results of the Atrial Fibrillation and Congestive Heart Failure (AF-CHF) trial.

RECENT FINDINGS

The Atrial Fibrillation and Congestive Heart Failure trial was a randomized trial involving patients with both atrial fibrillation and heart failure. The trial was designed to compare the maintenance of sinus rhythm with the control of ventricular rate in patients with left ventricular dysfunction, heart failure and a history of atrial fibrillation. There was no significant difference in the rate of death from cardiovascular causes in the rhythm-control group as compared with the rate-control strategy. In addition, there was no significant difference in any of the secondary outcomes including death from any cause, worsening heart failure or stroke. The rate-control strategy eliminated the need for repeated cardioversion and reduced rates of hospitalization.

SUMMARY

The results of the Atrial Fibrillation and Congestive Heart Failure trial indicate that a routine strategy of rhythm control does not reduce rate of death and suggest that rate control should be considered a primary approach for patients with atrial fibrillation and heart failure.

Coherence and correspondence in medicine

Many controversies in medical science can be framed as tension between a coherence approach (which seeks logic and explanation) and a correspondence approach (which emphasizes empirical correctness). In many instances, a coherence-based theory leads to an understanding of disease that is not supported by empirical evidence. Physicians and patients alike tend to favor the coherence approach even in the face of strong, contradictory correspondence evidence. Examples include the management of atrial fibrillation, treatment of acute bronchitis, and the use of Vitamin E to prevent heart disease. Despite the frequent occurrence of controversy stemming from coherence-correspondence conflicts, medical professionals are generally unaware of these terms and the philosophical traditions that underlie them. Learning about the coherence-correspondence distinction and using the best of both approaches could not only help reconcile controversy but also lead to striking advances in medical science.

Benefits and risks of long-term amiodarone therapy for persistent atrial fibrillation: a meta-analysis

OBJECTIVE

To assess whether amiodarone, as part of a strategy to achieve sinus rhythm, is safe and effective compared with a placebo or rate control drug in patients with persistent atrial fibrillation (AF) of more than 30 days' duration.

METHODS

Randomized controlled trials comparing amiodarone with a placebo or rate control drug were identified through the EMBASE (January 1, 1988, to October 18, 2008), MEDLINE (January 1, 1966, to October 18, 2008), and Cochrane Controlled Trials Register (second issue 2008) databases with no language restrictions.

RESULTS

Twelve randomized controlled trials that involved a total of 5060 patients with persistent AF were considered. Amiodarone was more effective than a placebo or rate control drug in achieving sinus rhythm (21.3 vs 9.2 per 100 patient-years in sinus rhythm; relative risk [RR], 3.2; 95% confidence interval [CI], 1.9-5.5), and its use was not associated with an increased risk of long-term mortality (4.7 vs 3.9 per 100 patient-years; RR, 0.95; 95% CI, 0.8-1.1; P=.51; I2=0%). Cessation of amiodarone therapy because of intolerable adverse effects was more common compared with a placebo or rate control drug (10.7 vs 1.9 per 100 patient-years; RR, 3.0; 95% CI, 1.4-6.2; P<.001; I2=70%), but amiodarone was not associated with an increased incidence of hospitalizations (RR, 1.1; 95% CI, 0.6-2.1; P=.77; I2=90%).

CONCLUSION

Amiodarone, as part of a strategy to achieve and maintain sinus rhythm, appears to be safe and effective in patients with persistent AF. However, some patients may not tolerate the adverse effects of this agent.

Benefits and risks of long-term amiodarone therapy for persistent atrial fibrillation: a meta-analysis

OBJECTIVE

To assess whether amiodarone, as part of a strategy to achieve sinus rhythm, is safe and effective compared with a placebo or rate control drug in patients with persistent atrial fibrillation (AF) of more than 30 days' duration.

METHODS

Randomized controlled trials comparing amiodarone with a placebo or rate control drug were identified through the EMBASE (January 1, 1988, to October 18, 2008), MEDLINE (January 1, 1966, to October 18, 2008), and Cochrane Controlled Trials Register (second issue 2008) databases with no language restrictions.

RESULTS

Twelve randomized controlled trials that involved a total of 5060 patients with persistent AF were considered. Amiodarone was more effective than a placebo or rate control drug in achieving sinus rhythm (21.3 vs 9.2 per 100 patient-years in sinus rhythm; relative risk [RR], 3.2; 95% confidence interval [CI], 1.9-5.5), and its use was not associated with an increased risk of long-term mortality (4.7 vs 3.9 per 100 patient-years; RR, 0.95; 95% CI, 0.8-1.1; P=.51; I2=0%). Cessation of amiodarone therapy because of intolerable adverse effects was more common compared with a placebo or rate control drug (10.7 vs 1.9 per 100 patient-years; RR, 3.0; 95% CI, 1.4-6.2; P<.001; I2=70%), but amiodarone was not associated with an increased incidence of hospitalizations (RR, 1.1; 95% CI, 0.6-2.1; P=.77; I2=90%).

CONCLUSION

Amiodarone, as part of a strategy to achieve and maintain sinus rhythm, appears to be safe and effective in patients with persistent AF. However, some patients may not tolerate the adverse effects of this agent.

The rationale and design of the FORomegaARD Trial: A randomized, double-blind, placebo-controlled, independent study to test the efficacy of n-3 PUFA for the maintenance of normal sinus rhythm in patients with previous atrial fibrillation

BACKGROUND

Atrial fibrillation (AF) is associated with increased risk of death, thromboembolic complications, and a lowered quality of life. Despite this burden, pharmacologic agents for prevention of AF in patients who achieved normal sinus rhythm are of limited utility, mostly because of serious and frequent side effects. Thus, the availability of safer and more effective drugs may reduce the burden of disease.

TRIAL DESIGN

Patients aged > or =21 years with previous symptomatic AF and who have recovered normal sinus rhythm will be randomized to 1 g daily of omega-3-acid ethyl esters or identical placebo. To be included in the trial, patients must have either (a) at least 2 symptomatic episodes of documented AF in the 6 months before randomization, with the last episode occurring in the 14 to 90 days before randomization (paroxysmal AF), or (b) successful electrical or pharmacologic cardioversion for persistent AF. Ethical committees of 71 cardiology centers in 16 provinces of Argentina have qualified and approved the protocol and are expected to enroll 1,400 patients to test the primary end point of efficacy, which is survival free of AF during follow-up.

CONCLUSION

The Fish Oil Reserach with omega-3 for Atrial fibrillation Recurrence Delay (FORomegaARD) trial will determine whether pharmacologic supplementation with 1 g of omega-3-acid ethyl esters can reduce AF recurrence in patients with previous AF who have recovered normal sinus rhythm.

Internal medicine physicians' perceptions regarding rate versus rhythm control for atrial fibrillation

Atrial fibrillation (AF) is often managed by general internal medicine physicians. Available data suggest that guidelines regarding AF management are often not followed, but the reasons for this remain unknown. The aim of this study was to assess the knowledge and beliefs of internists regarding strategies to treat AF. A national electronic survey of internal medicine physicians regarding their perceptions of optimal AF management, with an emphasis on the rationale for choosing a rhythm- or rate-control strategy, was conducted. One hundred forty-eight physicians from 36 different states responded (representing > or =19% of unique e-mails opened). Half the respondents reported managing their patients with AF independently without referral to cardiologists. Seventy-three percent of participants believed that a rhythm-control strategy conveys a decreased stroke risk, 64% believed that there is a mortality benefit to rhythm control, and 55% thought that it would help avoid long-term anticoagulation. Comparing those who preferred a rhythm-control strategy to everyone else, those who favored rhythm control statistically significantly more often believed that rhythm control reduces the risk for stroke (96% vs 67%, p = 0.009) and that rhythm control allows the discontinuation of anticoagulation therapy (76% vs 49%, p = 0.045). In conclusion, contrary to available data in clinical trials and recent guidelines regarding the rationale for choosing a rhythm-control strategy in treating patients with AF, most study participants believed that rhythm control decreases stroke risk, decreases mortality, and allows the discontinuation of anticoagulation therapy. These prevalent misconceptions may substantially contribute to guideline nonadherence.

Advances in the management of atrial fibrillation in congestive heart failure

Atrial fibrillation, a common problem in patients with heart failure, is associated with increased mortality and morbidity. Pharmacological as well as invasive management and the endpoints of such management are complex. Recent randomized trials indicate that a rate-control strategy, along with anticoagulation treatment with warfarin, when appropriate, has a similar outcome in terms of mortality and morbidity as rhythm control, and could, therefore, be considered as the primary management strategy for atrial fibrillation in patients with heart failure.

[Rate versus rhythm control with and without heart failure]

Atrial fibrillation and congestive heart failure are frequently associated with complex interactions. Patients with both diseases bear a sophisticated therapeutic challenge for the attending physician. The approach to treat atrial fibrillation differs for patients with and without heart failure in several aspects. Basic requirements are the treatment of the underlying diseases and prophylaxis of thromboembolic complications. Rate and rhythm control are the two main therapeutic strategies for atrial fibrillation according to the current guidelines. Large trials including the recently published AF-CHF study (Atrial Fibrillation - Congestive Heart Failure) failed to demonstrate a difference in mortality for both strategies. Thus, the therapeutic decision is mainly based on the patient's symptoms to improve quality of life. Rate control should be applied to asymptomatic patients or if rhythm control has already failed. If beta-blockers and digoxin have failed to control heart rate, His ablation with pacemaker implantation can be considered. In patients without heart disease, class I antiarrhythmic drugs and, in case of ineffectiveness, amiodarone or catheter ablation are recommended for rhythm control. First data concerning catheter ablation of atrial fibrillation in heart failure are promising and randomized studies are on the way. Rhythm control remains first-line therapy in recent-onset or highly symptomatic paroxysmal or persistent atrial fibrillation patients with and without heart failure.

Catheter Ablation Versus Antiarrhythmic Drugs for Atrial Fibrillation

Background— The mainstay of treatment for atrial fibrillation (AF) remains pharmacological; however, catheter ablation has increasingly been used over the last decade. The relative merits of each strategy have not been extensively studied.

Methods and Results— We conducted a randomized multicenter comparison of these 2 treatment strategies in patients with paroxysmal AF resistant to at least 1 antiarrhythmic drug. The primary end point was absence of recurrent AF between months 3 and 12, absence of recurrent AF after up to 3 ablation procedures, or changes in antiarrhythmic drugs during the first 3 months. Ablation consisted of pulmonary vein isolation in all cases, whereas additional extrapulmonary vein lesions were at the discretion of the physician. Crossover was permitted at 3 months in case of failure. Echocardiographic data, symptom score, exercise capacity, quality of life, and AF burden were evaluated at 3, 6, and 12 months by the supervising committee. Of 149 eligible patients, 112 (18 women [16%]; age, 51.1±11.1 years) were enrolled and randomized to ablation (n=53) or “new” antiarrhythmic drugs alone or in combination (n=59). Crossover from the antiarrhythmic drugs and ablation groups occurred in 37 (63%) and 5 patients (9%), respectively ( P =0.0001). At the 1-year follow-up, 13 of 55 patients (23%) and 46 of 52 patients (89%) had no recurrence of AF in the antiarrhythmic drug and ablation groups, respectively ( P <0.0001). Symptom score, exercise capacity, and quality of life were significantly higher in the ablation group.

Conclusion— This randomized multicenter study demonstrates the superiority of catheter ablation over antiarrhythmic drugs in patients with AF with regard to maintenance of sinus rhythm and improvement in symptoms, exercise capacity, and quality of life.

Omega-3 fatty acid supplementation reduces one-year risk of atrial fibrillation in patients hospitalized with myocardial infarction

PURPOSE

Current strategies for avoiding atrial fibrillation (AF) are of limited value. We aim to assess the relationship between omega-3 fatty acids (n-3 PUFA) and AF occurrence in post-myocardial infarction (MI) patients.

METHODS

A population study, linking hospital discharge records, prescription databases, and vital statistics, was conducted and included all consecutive patients with MI (ICD-9: 410) in six Italian local health authorities over a 3-year period. A propensity score (PS)-based, 5-to-1, greedy 1:1 matching algorithm was used to check consistency of results. Sensitivity analysis was performed to assess the robustness of findings.

RESULTS

N-3 PUFA reduced the relative risk of the hospitalization for AF [hazard ratio (HR) 0.19, 95% CI 0.07-0.51] and was associated with a further and complementary reduction in all-cause mortality (HR 0.15, 95% CI 0.05-0.46). PS-based matched analysis and sensitivity analysis confirmed the main results.

CONCLUSION

n-3 PUFA reduced both all-cause mortality and incidence of 1-year AF in patients hospitalized with MI.

Comparison of the Impact of the Atrial Fibrillation Follow-Up Investigation of Rhythm Management Trial on Prescribing Patterns: A Time-Series Analysis

Background:

The AFFIRM (Atrial Fibrillation Follow-Up Investigation of Rhythm Management) trial demonstrated that rate control and rhythm control strategies result in similar survival and quality of life for patients with atrial fibrillation (AF). Because of superior safety and lower cost, rate control is now the recommended strategy (or the management of most elderly, high-risk AF patients.

Objective:

To determine the extent to which the AFFIRM trial results have been adopted into actual practice.

Methods:

We conducted a time-series analysis of 3 population-based cohorts of patients with AF who were 66 years of age or older in Pennsylvania and Ontario. We stratified patients in Ontario by socioeconomic status (SES) and examined changes in quarterly prescription rates for rate control and rhythm controlling medications as well as cardioversion procedures before and after publication of the AFFIRM trial.

Results:

The publication of the AFFIRM trial resulted in statistically significant reductions in the use of rhythm controlling medications in all 3 cohorts (p < 0.01). The magnitude of these changes in the non-low SES Canadian cohort was approximately 1% per quarter and was greater than the magnitude observed in the other cohorts (p < 0.001). The use of cardioversion procedures also decreased in all study regions (p < 0.01). In contrast, AFFIRM publication was also associated with a small increase in the use of rate controlling medications in Canada (p < 0.01) but not in the US (p = 0.23).

Conclusions:

Publication of the AFFIRM trial resulted in small but statistically significant changes in the care of patients with AF.

A contemporary look at classic trials in atrial fibrillation: what do they really show and how might they apply to future therapies?

Atrial fibrillation (AF) is a common cardiac arrhythmia associated with significant morbidity, decreased exercise tolerance, and impairment of quality of life (QOL). Primary treatment objectives are either to restore and/or maintain sinus rhythm or to achieve satisfactory rate control. There are 5 landmark randomized trials comparing rhythm and rate control strategies that have reported equivalence in overall survival, and data from several trials suggest that the appropriate use of either approach leads to improvement in QOL. Study limitations (eg, trial design, analytic methodology, patient selection criteria, and lack of specificity of therapeutic intervention), however, have made the applicability of findings to a general AF patient population difficult. Although the optimal strategy remains unclear, an important first step in AF management is the proper identification and stratification of patients who require therapy. Given the currently available pharmacologic agents and procedures, as-needed therapy may be a reasonable approach in patients with intermittent AF, whereas the pursuit of sinus rhythm may be warranted in the balance of patients who remain symptomatic despite rate control therapy. The overarching treatment goal should be to provide individualized care based on patient characteristics at presentation, with appropriate consideration given to potential treatment-related adverse effects. Importantly, as the armamentarium of AF management strategies is broadened, the risk/efficacy balance must continue to be evaluated on a patient-specific basis.

Rhythm control versus rate control for atrial fibrillation and heart failure

BACKGROUND

It is common practice to restore and maintain sinus rhythm in patients with atrial fibrillation and heart failure. This approach is based in part on data indicating that atrial fibrillation is a predictor of death in patients with heart failure and suggesting that the suppression of atrial fibrillation may favorably affect the outcome. However, the benefits and risks of this approach have not been adequately studied.

METHODS

We conducted a multicenter, randomized trial comparing the maintenance of sinus rhythm (rhythm control) with control of the ventricular rate (rate control) in patients with a left ventricular ejection fraction of 35% or less, symptoms of congestive heart failure, and a history of atrial fibrillation. The primary outcome was the time to death from cardiovascular causes.

RESULTS

A total of 1376 patients were enrolled (682 in the rhythm-control group and 694 in the rate-control group) and were followed for a mean of 37 months. Of these patients, 182 (27%) in the rhythm-control group died from cardiovascular causes, as compared with 175 (25%) in the rate-control group (hazard ratio in the rhythm-control group, 1.06; 95% confidence interval, 0.86 to 1.30; P=0.59 by the log-rank test). Secondary outcomes were similar in the two groups, including death from any cause (32% in the rhythm-control group and 33% in the rate-control group), stroke (3% and 4%, respectively), worsening heart failure (28% and 31%), and the composite of death from cardiovascular causes, stroke, or worsening heart failure (43% and 46%). There were also no significant differences favoring either strategy in any predefined subgroup.

CONCLUSIONS

In patients with atrial fibrillation and congestive heart failure, a routine strategy of rhythm control does not reduce the rate of death from cardiovascular causes, as compared with a rate-control strategy. (ClinicalTrials.gov number, NCT00597077.)