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

Antiarrhythmics for maintaining sinus rhythm after cardioversion of atrial fibrillation

BACKGROUND

Atrial fibrillation (AF) is the most frequent sustained arrhythmia. AF recurs frequently after restoration of normal sinus rhythm. Antiarrhythmic drugs have been widely used to prevent recurrence, but the effect of these drugs on mortality and other clinical outcomes is unclear.

OBJECTIVES

To determine, in patients who recovered sinus rhythm after AF, the effect of long-term treatment with antiarrhythmic drugs on death, stroke and embolism, adverse effects, pro-arrhythmia, and recurrence of AF.

SEARCH METHODS

We updated the searches of CENTRAL on The Cochrane Libary (Issue 1 of 4, 2010), MEDLINE (1950 to February 2010) and EMBASE (1966 to February 2010). The reference lists of retrieved articles, recent reviews and meta-analyses were checked.

SELECTION CRITERIA

Two independent reviewers selected randomised controlled trials comparing any antiarrhythmic with a control (no treatment, placebo or drugs for rate control) or with another antiarrhythmic, in adults who had AF and in whom sinus rhythm was restored. Post-operative AF was excluded.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed quality and extracted data. Studies were pooled, if appropriate, using Peto odds ratio (OR). All results were calculated at one year of follow-up.

MAIN RESULTS

In this update, 11 new studies met inclusion criteria, making a total of 56 included studies, comprising 20,771 patients. Compared with controls, class IA drugs quinidine and disopyramide (OR 2.39, 95% confidence interval (95%CI) 1.03 to 5.59, number needed to harm (NNH) 109, 95%CI 34 to 4985) and sotalol (OR 2.47, 95%CI 1.2 to 5.05, NNH 166, 95%CI 61 to 1159) were associated with increased all-cause mortality. Other antiarrhythmics did not seem to modify mortality.Several class IA (disopyramide, quinidine), IC (flecainide, propafenone) and III (amiodarone, dofetilide, dronedarone, sotalol) drugs significantly reduced recurrence of AF (OR 0.19 to 0.70, number needed to treat (NNT) 3 to 16). Beta-blockers (metoprolol) also reduced significantly AF recurrence (OR 0.62, 95% CI 0.44 to 0.88, NNT 9).All analysed drugs increased withdrawals due to adverse affects and all but amiodarone, dronedarone and propafenone increased pro-arrhythmia. We could not analyse other outcomes because few original studies reported them.

AUTHORS' CONCLUSIONS

Several class IA, IC and III drugs, as well as class II (beta-blockers), are moderately effective in maintaining sinus rhythm after conversion of atrial fibrillation. However, they increase adverse events, including pro-arrhythmia, and some of them (disopyramide, quinidine and sotalol) may increase mortality. Possible benefits on clinically relevant outcomes (stroke, embolisms, heart failure) remain to be established.

Hypertension and atrial fibrillation: diagnostic approach, prevention and treatment. Position paper of the Working Group 'Hypertension Arrhythmias and Thrombosis' of the European Society of Hypertension

Hypertension is the most common cardiovascular disorder and atrial fibrillation is the most common clinically significant arrhythmia. Both these conditions frequently coexist and their prevalence increases rapidly with aging. There are different risk factors and clinical conditions predisposing to the development of atrial fibrillation, but due its high prevalence, hypertension is still the main risk factor for the development of atrial fibrillation. Several pathophysiologic mechanisms (such as structural changes, neurohormonal activation, fibrosis, atherosclerosis, etc.) have been advocated to explain the onset of atrial fibrillation. The presence of atrial fibrillation per se increases the risk of stroke but its coexistence with high blood pressure leads to an abrupt increase of cardiovascular complications. Different risk models are available for the risk stratification and the prevention of thromboembolism in patients with atrial fibrillation. In all of them hypertension is present and is an important risk factor. Antihypertensive treatment may contribute to reduce this risk, and it seems some classes are superior to others in the prevention of new-onset atrial fibrillation and prevention of stroke. Antithrombotic treatment with warfarin is effective in the prevention of thromboembolic events, although quite recently, new classes of anticoagulants that do not require international normalized ratio monitoring have been introduced with promising results.

Preventative Measures of Stroke in Patients With Atrial Fibrillation

Atrial fibrillation (AF) is the commonest sustained cardiac arrhythmia and is associated with increased morbidity and mortality due to stroke and thrombo-embolism. In patients with AF, strokes are usually more severe, resulting in longer hospital stays, worse disability and considerable healthcare costs. The prevention of stroke therefore is crucial in the management of AF. Stroke risk stratification tools can be used to determine patients at higher risk of stroke, and if no contraindications are present oral anticoagulation (OAC) therapy can be initiated. Despite the strong evidence for the benefit of OAC in stroke prevention in patients with AF, the use of thromboprophylaxis remains inadequate. The key measures to prevent stroke in patients with AF include: adequate stroke risk assessment and thrombo-prophylaxis; prompt initiation of OAC and avoidance of interruptions; earlier detection of AF; and education to overcome the under-usage of OAC in elderly patients.

Atrial fibrillation management, outcomes and predictors of stable disease in daily practice: prospective non-interventional study

BACKGROUND

We aimed to describe the current management of patients with atrial fibrillation (AF) by cardiologists, and to identify predicting factors for a stable disease course.

METHODS

2753 consecutive patients with ECG-confirmed AF in the previous 12 months were documented in a 1-year observational (non-interventional) study from 616 centers. Stable disease was defined as having neither AF related intervention nor change in antiarrhythmic therapy in the previous 12 months. Stepwise selection of parameters for multivariate regression was used to identify factors for stable AF.

RESULTS

At baseline, paroxysmal AF was reported in 33.5%, persistent in 26.7%, and permanent in 39.7%; rate control alone was the prevailing antiarrhythmic strategy (64.2%). Drugs for thromboembolic prevention were administered in 93.8%, with a clear predominance of oral anticoagulants (OAC), alone or in combination with antiplatelet drugs. Electrical or pharmacological conversions were reported in 23.6%. A total of 96 (3.5%) patients in the total cohort experienced stroke, 72 patients (2.6%) TIA, and 24 (0.9%) arterial embolism. 26% were hospitalized during follow-up (0.4 events per patient), and 9.4% developed incident heart failure (42% prevalence at follow-up). The rate of stable patients was 43.4%. In the multivariate model male gender, history of stroke, and permanent (vs. persistent) AF were associated with stable disease. Conversely, the factors chronic heart failure, impaired left ventricular function, rhythm-control (vs. other), OAC and antiplatelet therapy were significantly correlated with unstable disease.

CONCLUSIONS

The relatively low proportion of stable patients and in particular, the high hospitalization and stroke rate indicate difficulties in everyday management of patients with AF.

One-year treatment persistence and potential adverse events among patients with atrial fibrillation treated with amiodarone or sotalol: a retrospective claims database analysis

BACKGROUND

The risk-benefit profile of antiarrhythmic drugs (AADs) affects the choice of pharmacotherapy for maintenance of sinus rhythm. Adverse events (AEs) associated with AADs may influence patient compliance and compromise the management of atrial fibrillation (AF). There are limited data on the incidence of AEs or persistence with AADs outside the clinical trial environment.

OBJECTIVE

This study provides treatment persistence and AE data for patients with AF receiving treatment with amiodarone or sotalol, 2 of the most widely used AADs in the United States.

METHODS

In this retrospective cohort study, patients satisfying the following criteria were identified from the US MarketScan claims databases: (1) age ≥18 years with a pharmacy claim for oral amiodarone or sotalol between 2004 and 2007; (2) ≥1 inpatient/outpatient medical claim with an AF diagnosis <90 days before the earliest (index) pharmacy claim; and (3) ≥12 months' continuous enrollment before and after the index pharmacy claim. Prespecified AE rates were compared between treatment cohorts during active treatment.

RESULTS

Among 77,093 AF patients with ≥1 claim for amiodarone or sotalol, 3459 met all inclusion criteria (mean age, 70.8 years; 61.6% male; mean Charlson Comorbidity Index [CCI], 1.58), of whom 2392 received amiodarone (mean age, 72.2 years; 62.5% male; mean CCI, 1.8) and 1067 received sotalol (mean age, 67.5 years; 59.7% male; mean CCI, 1.1). Persistence was higher among the sotalol cohort than the amiodarone cohort (53.2% vs 30.6% at 12 months; P < 0.001). Postindex versus preindex comparisons revealed increases in cardiovascular AE rates in both cohorts. Intercohort comparisons showed higher rates of cardiovascular AEs (594 vs 339 patients/1000 patient-years; P < 0.001) and pulmonary AEs (128 vs 61 patients/1000 patient-years; P < 0.001) during active amiodarone treatment.

CONCLUSIONS

Among the population analyzed, patients with AF receiving amiodarone versus sotalol therapy had differing clinical characteristics. Patients experienced frequent AEs (particularly cardiovascular events) with amiodarone and sotalol, and many discontinued treatment during the first year.

Comparison of electrophysiological and antiarrhythmic effects of vernakalant, ranolazine, and sotalol in canine pulmonary vein sleeve preparations

BACKGROUND

Vernakalant (VER) is a relatively atrial-selective antiarrhythmic drug capable of blocking potassium and sodium currents in a frequency- and voltage-dependent manner. Ranolazine (RAN) is a sodium-channel blocker shown to exert antiarrhythmic effects in pulmonary vein (PV) sleeves. dl-Sotalol (SOT) is a β-blocker commonly used in the rhythm-control treatment of atrial fibrillation. This study evaluated the electrophysiological and antiarrhythmic effects of VER, RAN, and SOT in canine PV sleeve preparations in a blinded fashion.

METHODS

Transmembrane action potentials were recorded from canine superfused PV sleeve preparations exposed to VER (n = 6), RAN (n = 6), and SOT (n = 6). Delayed afterdepolarizations were induced in the presence of isoproterenol and high-calcium concentrations by periods of rapid pacing.

RESULTS

In PV sleeves, VER, RAN, and SOT (3-30 μM) produced small (10-15 ms) increases in action potential duration. The effective refractory period, diastolic threshold of excitation, and the shortest S(1)-S(1) cycle length permitting 1:1 activation were significantly increased by VER and RAN in a rate- and concentration-dependent manner. VER and RAN significantly reduced V(max) in a concentration- and rate-dependent manner. SOT did not significantly affect the effective refractory period, V(max), diastolic threshold of excitation, or the shortest S(1)-S(1) cycle length permitting 1:1 activation. All 3 agents (3-30 μM) suppressed delayed afterdepolarization-mediated triggered activity induced by isoproterenol and high calcium.

CONCLUSIONS

In canine PV sleeves, the effects of VER and RAN were similar and largely characterized by concentration- and rate-dependent depression of sodium-channel-mediated parameters, which were largely unaffected by SOT. All 3 agents demonstrated an ability to effectively suppress delayed afterdepolarization-induced triggers of atrial arrhythmia.

Novel Pharmacological Interventions to Maintain Sinus Rhythm after DC Cardioversion

Despite the availability of potentially curative interventions for atrial fibrillation, there remains an important role for conventional anti-arrhythmic therapy and anti-coagulation combined with direct current cardioversion. Unfortunately, the latter approach is disturbed by high recurrence rates of atrial fibrillation. In recent years, several adjunctive therapies have emerged which may facilitate the maintenance of sinus rhythm. These novel therapies and their potential mechanisms of action are reviewed in this article.

Atrial fibrillation

The management of atrial fibrillation has evolved greatly in the past few years, and many areas have had substantial advances or developments. Recognition of the limitations of aspirin and the availability of new oral anticoagulant drugs that overcome the inherent drawbacks associated with warfarin will enable widespread application of effective thromboprophylaxis with oral anticoagulants. The emphasis on stroke risk stratification has shifted towards identification of so-called truly low-risk patients with atrial fibrillation who do not need antithrombotic therapy, whereas oral anticoagulation therapy should be considered in patients with one or more risk factors for stroke. New antiarrhythmic drugs, such as dronedarone and vernakalant, have provided some additional opportunities for rhythm control in atrial fibrillation. However, the management of the disorder is increasingly driven by symptoms. The availability of non-pharmacological approaches, such as ablation, has allowed additional options for the management of atrial fibrillation in patients who are unsuitable for or intolerant of drug approaches.

Benefit-risk assessment of current antiarrhythmic drug therapy of atrial fibrillation

Over the last decade, several rhythm-versus rate-control trails in patients with atrial fibrillation (AF) have failed to demonstrate benefit of the rhythm control strategy with respect to mortality and morbidity. This had let to the guideline recommendation that antiarrhythmic drug therapy should be considered predominantly for symptomatic improvement of patients. Recent trails and meta-analyses have demonstrated that amiodarone is the most antiarrhythmic drug currently available. However, its use has been associated with many adverse effects. Currently, dronedarone is the only available antiarrhythmic drug which has shown a reduction in cardiovascular hospitalizations in medium-risk AF patients. However, the drug was associated with increased mortality in patients with recently decompensated heart failure. Hence, antiarrhythmic drug therapy has to be evaluated in patients with AF on an individual patients basis.

Comparison of rate control versus rhythm control for management of atrial fibrillation in patients with coexisting heart failure: a cost-effectiveness analysis

STUDY OBJECTIVE

To compare lifetime costs and health outcomes of rate control versus rhythm control for management of atrial fibrillation in patients with coexisting heart failure from the third-party payer perspective.

DESIGN

A Markov decision analysis model constructed from costs, utility, and transition probability inputs obtained from randomized clinical trials and publically available databases.

PATIENTS

A simulated cohort aged 65 years or older with persistent or paroxysmal atrial fibrillation and heart failure.

MEASUREMENTS AND MAIN RESULTS

Markov states for rhythm control were cardioversion plus amiodarone and maintenance amiodarone, and those for rate control were β-blocker, digoxin, and calcium channel blocker. Transition states included treatment success, hospitalizations for atrial fibrillation and/or heart failure, and severe adverse effects. Economic inputs included cost for drugs, cost of hospitalizations for atrial fibrillation and/or heart failure, and cost of management of severe adverse effects. Costs were measured in 2009 U.S. dollars, and clinical outcomes in quality-adjusted life-years (QALYs). One-way and multivariable sensitivity analyses were conducted. Uncertainty intervals (UIs) were obtained from probabilistic sensitivity analyses. Rate control was found to be less costly and more effective than rhythm control. Base case and probabilistic sensitivity analyses cost and effectiveness values for rate control were $7231 (95% UI $5517-9016) and 2.395 QALYs (95% UI 2.366-2.424 QALYs); whereas those for rhythm control were $16,291 (95% UI $11,033-21,434) and 2.197 QALYs (95% UI 2.155-2.237 QALYs). No critical values were found for any model parameters in the one-way sensitivity analyses. The cost-effectiveness acceptability curves showed that rate control was considered cost-effective in 100% of cases at willingness-to-pay ratios between $0 and $200,000/QALY.

CONCLUSION

Rate control is less costly and more effective than rhythm control and should be the initial treatment for atrial fibrillation among patients with coexisting heart failure.

Atrial fibrillation: established and innovative methods of evaluation and treatment

BACKGROUND

5% to 8% of 70-year-olds and some 10% of persons over age 80 have atrial fibrillation (AF).

METHODS

Selective literature review.

RESULTS

New scoring schemes (CHA(2)DS(2)-VASc score, HAS-BLED score) have been introduced to enable more accurate estimation of the risk of stroke and hemorrhage in patients with AF. These scores are calculated on the basis of clinical data (left ventricular dysfunction, hypertension, age, diabetes, prior stroke, vascular diseases, sex, renal or hepatic dysfunction, bleeding, labile INR values, consumption of medications and alcohol) and are used to determine the potential indication for, and appropriate type of, anticoagulation in the individual AF patient. Hemodynamically unstable patients with rapid AF should undergo DC cardioversion at once. Patients with permanent AF should be given beta-blockers, calcium antagonists, or digitalis for rate control, with a target rate below 110/minute. A recently introduced drug, dronedarone, is used for rhythm control and has relatively few side effects. Patients with AF and impaired left ventricular function should be given amiodarone. Rhythm control has not been found to prolong life any more than rate control. Patients with a CHA(2)DS(2)-VASc score of 2 or above should be orally anticoagulated. Those with a score of 1 can be treated with aspirin (75 to 325 mg daily); those with a score of 0 do not need antithrombotic treatment. A HAS-BLED score of 3 or above is associated with a high risk of bleeding. Pulmonary vein isolation is an established method of treating symptomatic AF, with a success rate of 60% to 80%. Surgical procedures are possible in AF patients who need additional cardiac surgery.

CONCLUSION

The treatment strategy for AF must be individualized on the basis of the patient's clinical manifestations. The mainstay of treatment is anticoagulation; the indication for anticoagulation depends on the patient's age, underlying disease, and left ventricular function.

Novel pharmacological targets for the rhythm control management of atrial fibrillation

Atrial fibrillation (AF) is a growing clinical problem associated with increased morbidity and mortality. Development of safe and effective pharmacological treatments for AF is one of the greatest unmet medical needs facing our society. In spite of significant progress in non-pharmacological AF treatments (largely due to the use of catheter ablation techniques), anti-arrhythmic agents (AADs) remain first line therapy for rhythm control management of AF for most AF patients. When considering efficacy, safety and tolerability, currently available AADs for rhythm control of AF are less than optimal. Ion channel inhibition remains the principal strategy for termination of AF and prevention of its recurrence. Practical clinical experience indicates that multi-ion channel blockers are generally more optimal for rhythm control of AF compared to ion channel-selective blockers. Recent studies suggest that atrial-selective sodium channel block can lead to safe and effective suppression of AF and that concurrent inhibition of potassium ion channels may potentiate this effect. An important limitation of the ion channel block approach for AF treatment is that non-electrical factors (largely structural remodeling) may importantly determine the generation of AF, so that "upstream therapy", aimed at preventing or reversing structural remodeling, may be required for effective rhythm control management. This review focuses on novel pharmacological targets for the rhythm control management of AF.

A dedicated cardioversion unit for the treatment of atrial fibrillation. Reducing costs by optimizing processes

BACKGROUND

Atrial fibrillation (AF) is the most frequent arrhythmia seen in man. Many patients are admitted to the hospital to undergo transesophageal echocardiography (TEE) for thrombus exclusion and subsequent electrical cardioversion (ECV) under deep sedation to restore sinus rhythm. The present study investigated prospectively how workflow optimization can contribute to reducing time and costs in AF patients scheduled for ECV in an outpatient setting.

METHODS

A cardioversion unit (CU) was established and equipped to perform all ECV-associated procedures. Between November 2007 and January 2009, ECV was performed in 115 patients in an outpatient setting. Three different settings were tested for ECV: (1) usual care (n = 19): preparation/follow-up in the outpatient clinic, blood testing in the central hospital laboratory (CHL), TEE in the echocardiography laboratory, and ECV in the intensive care unit; (2) optimized process 1 (n = 41): preparation/follow-up, TEE + ECV during one sedation in the CU, blood testing in the CHL; (3) optimized process 2 (n = 55): preparation/follow-up, TEE + ECV and point of care (POC) blood testing in the CU. All procedure-related costs were listed and classified according to material, human resources, and infrastructure.

RESULTS

From setting 1 to 3, there was a significant decrease in procedural time from 480 ± 105 min to 205 ± 85 min (p < 0.001). Likewise, ECV-associated costs could be reduced from 683 ± 104 <euro> to 299 ± 63 <euro> (p < 0.001).

CONCLUSION

Establishing a CU for AF enables a more than 50% reduction in procedural time and costs. A combination of TEE and ECV in one sedation and POC testing in the CU were the major contributors to this time and cost reduction.

Rationale and current perspective for early rhythm control therapy in atrial fibrillation

Atrial fibrillation (AF) is the most common sustained arrhythmia and an important source for mortality and morbidity on a population level. Despite the clear association between AF and death, stroke, and other cardiovascular events, there is no evidence that rhythm control treatment improves outcome in AF patients. The poor outcome of rhythm control relates to the severity of the atrial substrate for AF not only due to the underlying atrial remodelling process but also due to the poor efficacy and adverse events of the currently available ion-channel antiarrhythmic drugs and ablation techniques. Data suggest, however, an association between sinus rhythm maintenance and improved survival. Hypothetically, sinus rhythm may also lead to a lower risk of stroke and heart failure. The presence of AF, thus, seems one of the modifiable factors associated with death and cardiovascular morbidity in AF patients. Patients with a short history of AF and the underlying heart disease have not been studied before. It is fair to assume that abolishment of AF in these patients is more successful and possibly also safer, which could translate into a prognostic benefit of early rhythm control therapy. Several trials are now investigating whether aggressive early rhythm control therapy can reduce cardiovascular morbidity and mortality and increase maintenance of sinus rhythm. In the present paper we describe the background of these studies and provide some information on their design.

Rate vs rhythm control in patients with atrial fibrillation and heart failure: a systematic review and meta-analysis of randomised controlled trials

BACKGROUND

Atrial fibrillation (AF) is a common arrhythmia that can promote or worsen heart failure (HF). Our purpose was to compare the effects of rate and rhythm control in patients with atrial fibrillation and heart failure.

METHODS

We developed a systematic search in August 2010 through CENTRAL and MEDLINE databases to identify randomised controlled trials (RCTs) comparing rate control with rhythm control in patients with both AF and HF. We analysed mortality, hospitalisations, stroke/thromboembolic events, quality of life, and drugs adverse events. Relative risks (RR) and 95% confidence intervals (95% CI) were calculated for mortality and hospitalisations. The remaining outcomes were analysed qualitatively.

RESULTS

Four RCTs with a total of 2486 patients with atrial fibrillation and heart failure were identified. Mortality and stroke/thromboembolic events were not significantly different in rate and rhythm control arms [RR 1.03; 95% CI: 0.90-1.17] and [RR 1.09; 95% CI: 0.61-1.96], respectively. Hospitalisations were less frequent with rate control than with rhythm control [RR 0.92; 95% CI: 0.86-0.98; p=0.008], in 3 studies involving 2425 patients. Number needed to treat to prevent one hospitalisation was 19 patients.

CONCLUSIONS

In patients with AF and HF, rate control compared with rhythm control showed inferior risk of hospitalisation.

Management of patients with atrial fibrillation: specific considerations for the old age

Atrial fibrillation (AF) is the commonest of all sustained arrhythmias, and most of the patients seeking medical therapy are in the elderly age group. The management of these patients is particularly difficult due to associated comorbidities. Hypertension, congestive heart failure, left ventricular hypertrophy, and coronary artery disease are often present in the elderly patient population, and therefore, antiarrhythmic drugs often fail due to side effects, proarrhythmia, or poor rhythm control. Recently, radiofrequency catheter ablation has been widely performed as an efficient therapy for recurrent, drug-refractory AF. Nevertheless, patients at old age were underrepresented in prior AF ablation trials, and the current guidelines for catheter ablation of AF recommend a noninvasive approach in the elderly patient group due to the lack of clinical data supporting ablation therapy. However, study results of our group and others are suggesting that catheter ablation is a safe and effective treatment for patients over the age of 65 years with symptomatic, drug-refractory AF, and therefore, patients should not be precluded from catheter ablation only on the basis of age. This paper discusses the pharmacological (rhythm control, rate control, and anticoagulation) and catheter management of AF in the elderly population.

Clinical characteristics and cardiovascular outcomes of hemodialysis patients with atrial fibrillation: a prospective follow-up study

BACKGROUND/AIMS

Among the cardiovascular complications in dialysis patients, atrial fibrillation (AF) is the most common arrhythmia. The purpose of this study was to clarify the characteristics and mortality of hemodialysis patients with AF, which are not completely elucidated.

METHODS

The prevalence of AF in patients undergoing hemodialysis in our institutions was assessed. Patients with AF (AF group) and without AF (control group) were included in this study. Patients in the control group were matched for several important clinical risk factors. For further analysis, AF patients were divided into two groups on the basis of the type of AF (chronic AF (CAF) and paroxysmal AF (PAF) groups). These patients were evaluated for their clinical characteristics, laboratory data and echocardiographic parameters and prospectively followed up for 48 months.

RESULTS

Among 328 study patients, 30 had AF (9.1%). Left atrial diameter (LAD) and the left ventricular mass index were significantly greater in the AF group than in the control group. Furthermore, cardiovascular and all-cause mortality and cumulative incidence of cardiovascular events were significantly higher in the AF group than in the control group, and tended to be higher in the CAF group.

CONCLUSIONS

Our findings demonstrated that the prevalence of AF as 9.1% in hemodialysis patients, and that AF, especially CAF, were associated with high mortality.

Sinus rhythm restoration and treatment success: insight from recent clinical trials

Atrial fibrillation (AF) is a common supraventricular tachyarrhythmia with substantial morbidity and mortality. This review briefly describes the mechanisms of AF development and progression, including electrical, structural, and contractile remodeling. In addition, the potential benefits of achieving and maintaining sinus rhythm are discussed. For example, rhythm control has been associated with improvements in left ventricular function, AF symptoms, exercise tolerance, the ability to perform activities of daily living, and quality of life. More recently, dronedarone, a noniodinated benzofuran derivative approved for use in the treatment of AF, was shown to significantly improve clinical outcomes including cardiovascular hospitalizations and death from any cause in A Placebo-Controlled, Double-Blind, Parallel Arm Trial to Assess the Efficacy of Dronedarone 400 mg bid for the Prevention of Cardiovascular Hospitalization or Death From Any Cause in Patients With Atrial Fibrillation/Atrial Flutter (ATHENA). The review concludes with an examination of AF treatment options and expectations. Evidence suggests that the complete absence of AF recurrence is not always achievable; however, complete restoration of sinus rhythm may not be necessary for patients to achieve clinically meaningful benefits. Copyright © 2011 Wiley Periodicals, Inc. The editorial assistance provided for this manuscript was funded by Sanofi-Aventis. The authors were fully responsible for all content and editorial decision, and received no financial support or other form of compensation related to the development of the paper. The authors have no other funding, financial relationships, or conflicts of interest to disclose.

Rhythm control strategies and the role of antiarrhythmic drugs in the management of atrial fibrillation: focus on clinical outcomes

Atrial fibrillation (AF) is a common disorder that significantly impacts the lives of affected patients. The restoration of sinus rhythm may prevent AF progression and reduce the occurrence of negative sequelae; however, available antiarrhythmic drugs (AADs) have largely failed to demonstrate significant benefit relative to rate control with respect to morbidity and mortality outcomes. The review commentary will address current knowledge regarding the pathologic mechanisms of AF, current trials that investigate rate and rhythm strategies, and future therapies that may change treatment approaches based on preliminary evidence suggesting a more favorable safety profile. The observed outcomes are likely a reflection of the limited efficacy plus poor safety and tolerability of available AADS. However, data from patients who attained and maintained sinus rhythm in a number of clinical studies demonstrate that the achievement of normal sinus rhythm can indeed reduce AF-associated morbidity and mortality. Furthermore, the results of trials designed to assess specific morbidity and mortality outcomes such as cardiovascular death hospitalization suggest that the development of safer AF therapies, whether pharmacologic or nonpharmacologic, can potentially improve clinical outcomes.

Strategies for the management of postoperative atrial fibrillation

Atrial fibrillation is an important complication of non-cardiothoracic surgery and is associated with higher hospital costs and increased morbidity. Strategies of rate versus rhythm control have been compared in several studies and patient populations and generally result in equivalent patient outcomes. Hemodynamically unstable patients should be electrically cardioverted for immediate restoration of sinus rhythm. However, in stable patients, a variety of pharmacologic agents can be selected for either rate or rhythm control. Selection of a particular agent should be based on a patient's comorbidities and preferences, as well as specific characteristics of each agent.

Atrial fibrillation in the aging heart: pharmacological therapy and catheter ablation in the elderly

The majority of patients with atrial fibrillation (AF) seeking medical treatment are in the elderly age group and the management of these patients is often complicated by comorbidities, challenging the pharmacological management of these patients. Owing to hypertension, congestive heart failure, left ventricular hypertrophy and coronary artery disease, antiarrhythmic treatment often fails due to side effects, proarrhythmia or poor rhythm control. In recent years, radiofrequency catheter ablation has been widely performed as an effective treatment for recurrent, drug-refractory AF. However, few elderly patients were included in prior AF catheter ablation studies and the current guidelines for catheter ablation of AF recommend a conservative approach in the elderly population owing to the absence of clinical data. However, study results from our group and others suggest that catheter ablation is a safe and effective treatment for patients over the age of 65 years with symptomatic, drug-refractory AF and, therefore, patients should not be excluded from catheter ablation on the basis of age alone. In this article, we discuss the pharmacological (rhythm control, rate control and anticoagulation) and catheter management of AF in the elderly population.

Presentation of atrial fibrillation and its management by cardiologists in the ambulatory and hospital setting: MOVE cross-sectional study

OBJECTIVE

The aim of the study was to collect comprehensive data on atrial fibrillation (AF) in ambulatory and hospital-based management in Germany.

METHODS

Consecutive patients with ECG-confirmed AF in the previous 12 months were documented in a non-interventional study in 638 physician offices (78.0%) or hospitals (12.7%).

RESULTS

Of the 3354 patients (mean age 68.9 ± 10.1 years; CHADS(2) score 1.9 ± 1.3), a total of 1136 (33.9%) had paroxysmal, 899 (26.8%) persistent, 1295 (38.6%) permanent and 24 (0.7%) unspecified AF. In the 12 months prior to documentation, pharmacological conversion was attempted in 18.2%, electric cardioversion in 17.5%, the combination of both in 31.2%, and catheter ablation of AF in 5.5%. Only 41.4% of patients met the definition of stable disease (having neither AF related intervention nor change in antiarrhythmic therapy in the previous 12 months). As treatment strategy, physicians stated rate control in 64%, rhythm control in 8%, and both in 19% (not reported: 8%). Patients received antiarrhythmic drugs of class IA in 1.3%, IC in 13.8%, II in 78.1%, III in 17.9%, IV in 9.7% and digitalis in 26.7%. Drugs for thromboembolic prevention (oral anticoagulants and/or antithrombotics) were administered in 81.5%. Hospitalisations for AF or associated diseases in the previous 12 months were reported in 34.2%. Possible limitations include the open, observational design, selection of physicians with particular interest in the field and selection of patients (i.e. underrepresentation of critically ill individuals).

CONCLUSIONS

While treatment rates with regards to the prevention of thromboembolic events were among the highest reported to date, the low proportion of stable patients and in particular, the high hospitalisation rate hint at difficulties in the management of patients with AF in clinical practice.

Pharmacological management of atrial fibrillation: one, none, one hundred thousand

atrial fibrillation (AF) is associated with a significant burden of morbidity and increased risk of mortality. Antiarrhythmic drug therapy remains a cornerstone to restore and maintain sinus rhythm for patients with paroxysmal and persistent AF based on current guidelines. However, conventional drugs have limited efficacy, present problematic risks of proarrhythmia and cause significant noncardiac organ toxicity. Thus, inadequacies in current therapies for atrial fibrillation have made new drug development crucial. New antiarrhythmic drugs and new anticoagulant agents have changed the current management of AF. This paper summarizes the available evidence regarding the efficacy of medications used for acute management of AF, rhythm and ventricular rate control, and stroke prevention in patients with atrial fibrillation and focuses on the current pharmacological agents.

The pathology and treatment of cardiac arrhythmias: focus on atrial fibrillation

Atrial fibrillation (AF) is the most frequently encountered sustained cardiac arrhythmia in clinical practice and a major cause of morbidity and mortality. Effective treatment of AF still remains an unmet medical need. Treatment of AF is based on drug therapy and ablative strategies. Antiarrhythmic drug therapy is limited by a relatively high recurrence rate and proarrhythmic side effects. Catheter ablation suppresses paroxysmal AF in the majority of patients without structural heart disease but is more difficult to achieve in patients with persistent AF or with concomitant cardiac disease. Stroke is a potentially devastating complication of AF, requiring anticoagulation that harbors the risk of bleeding. In search of novel treatment modalities, targeted pharmacological treatment and gene therapy offer the potential for greater selectivity than conventional small-molecule or interventional approaches. This paper summarizes the current understanding of molecular mechanisms underlying AF. Established drug therapy and interventional treatment of AF is reviewed, and emerging clinical and experimental therapeutic approaches are highlighted.

Review of contemporary antiarrhythmic drug therapy for maintenance of sinus rhythm in atrial fibrillation

Atrial fibrillation (AF) is the most common rhythm disturbance seen in clinical practice, and its prevalence and incidence are rising rapidly as the population ages with its attendant complications. Management of AF involves anticoagulation, and fortunately new drugs for long-term anticoagulation are now available. Maintenance of sinus rhythm, though intuitively better than rate control strategy, has not been shown to offer mortality benefit. Still, maintenance of sinus rhythm is considered an appropriate therapeutic strategy when symptoms are not adequately controlled with rate control. Though significant advances have been made in ablation techniques for AF, pharmacological therapy is still the first line of treatment for rate control and maintenance of sinus rhythm, given ease of use, noninvasive nature, and limited experience with catheter-based ablation techniques. Class IC and III agents (Vaughan Williams classification) form the backbone for pharmacological maintenance of sinus rhythm. Dronedarone, a recently approved class III agent, provides a significant advance because of its relatively safe side effect profile. Currently drugs with selective atrial channels blocking properties, like Vernakalant, are being tested in trials and may provide an opportunity to maintain sinus rhythm with limited toxicity. Large trials are also being conducted to better define the efficacy of catheter-based ablation strategy as first-line treatment. Here, we review the current status of commonly used antiarrhythmic medications for the maintenance of sinus rhythm in AF.

Management of atrial fibrillation: translating clinical trial data into clinical practice

Atrial fibrillation is a supraventricular tachyarrhythmia with significant consequences in terms of morbidity and mortality. In light of the limitations of available pharmacologic treatment options (suboptimal efficacy plus safety and tolerability issues), atrial fibrillation management should be individualized based on patient characteristics and comorbidities that could influence response to specific management approaches. The importance of adequate anticoagulation should not be overlooked. This review provides a practical guide for primary care physicians, internists, and cardiologists on current management strategies for atrial fibrillation, based on recent guidelines and current clinical data.

Twenty-five years in the making: flecainide is safe and effective for the management of atrial fibrillation

Atrial fibrillation (AF) is the most common arrhythmia in clinical practise and its prevalence is increasing. Over the last 25 years, flecainide has been used extensively worldwide, and its capacity to reduce AF symptoms and provide long-term restoration of sinus rhythm (SR) has been well documented. The increased mortality seen in patients treated with flecainide in the Cardiac Arrhythmia Suppression Trial (CAST) study, published in 1991, still deters many clinicians from using flecainide, denying many new AF patients a valuable treatment option. There is now a body of evidence that clearly demonstrates that flecainide has a favourable safety profile in AF patients without significant left ventricular disease or coronary heart disease. As a result of this evidence, flecainide is now recommended as one of the first-line treatment options for restoring and maintaining SR in patients with AF under current treatment guidelines. The objective of this article is to review the literature pertaining to the pharmacological characteristics, safety and efficacy of flecainide, and to place this drug in the context of current therapeutic management strategies for AF.

Diagnosis and treatment of atrial fibrillation in the acute care setting

PURPOSE

To discuss the causes of atrial fibrillation (AF), risk factors, and pathophysiology, and review current treatment guidelines for AF in the inpatient setting.

DATA SOURCES

Peer-reviewed medical and nursing journals, American College of Cardiology (ACC), American Heart Association (AHA), and European Society of Cardiology (ESC) practice guidelines.

CONCLUSIONS

There are many predisposing factors to AF and a variety of treatment modalities. Nurse practitioners (NPs) should acquaint themselves with the pathophysiology and evidence-based treatments in order to provide individually based care to patients.

IMPLICATIONS FOR PRACTICE

Pharmacological management is often warranted in patients with AF. NPs must be aware of updated clinical evidence in order to properly treat patients to provide symptomatic relief and improve quality of life.

Pharmacologic Conversion of Atrial Fibrillation and Atrial Flutter

Atrial fibrillation and atrial flutter are common arrhythmias in everyday clinical settings. Pharmacologic cardioversion (CV) is a simple and widely used strategy for the treatment of these arrhythmias, and many drugs are currently available. The choice of drug is strongly influenced by the time elapsed from atrial fibrillation onset and by a patient's clinical subset. Electrical direct-current CV is the treatment of choice in long-lasting forms; nevertheless, some agents also show efficacy in this setting. In addition, promising results come from studies on the efficacy and safety of new antiarrhythmic drugs and from therapeutic approaches that reduce the need for hospitalization and improve quality of life.

Characteristics and management of outpatients with history of or current atrial fibrillation: the observational French EPHA study

BACKGROUND

Limited French data are available for the different clinical types (paroxysmal, persistent and permanent) of atrial fibrillation and their comorbidities (AF).

AIMS

To provide contemporary insights into the characteristics and management of outpatients with a history of or current AF in France.

METHODS

EPHA is a national, observational, cross-sectional, multicentre descriptive study with retrospective data collection relating to the management, treatment and hospitalization of patients with AF.

RESULTS

One thousand three hundred and thirty-one patients (mean age: 74 +/- 11 years [55.7% > or =75 years]; 58.8% men) were included into the study between February 2009 and May 2009; their data were collected during the past 12 months. Of these, 38.2% had paroxysmal AF, 10.0% persistent AF and 51.8% permanent AF. Most patients had at least one cardiovascular risk factor (80.8%). Almost all patients (96.6%) had received an antiarrhythmic drug in the previous year, of which 59.6% received a rhythm control strategy (class I, class III) with or without rate control strategy (class II, class IV, digitalis) and 40.6% received a rate control strategy exclusively. Almost all (94.4%) patients were treated with an antithrombotic: 83.4% with a vitamin K antagonist and 21.9% with antiplatelet therapy. Almost one-fifth (18.4%) of patients had been hospitalized related to AF at least once in the previous year. Patients with paroxysmal and persistent AF were hospitalized more frequently (20.0% and 31.1%, respectively) than patients with permanent AF (14.8%).

CONCLUSIONS

About half of the patients had paroxysmal or persistent AF. Four-fifths of AF patients had at least one cardiovascular risk factor. The use of antiarrhythmic and antithrombotic treatments was very high. The rhythm control strategy was preferred in patients with paroxysmal or persistent AF.