Double-blind placebo-controlled trial of aprindine and digoxin for the prevention of symptomatic atrial fibrillation

Antiarrhythmics for maintaining sinus rhythm after cardioversion of atrial fibrillation

BACKGROUND

Atrial fibrillation is the most frequent sustained arrhythmia. Atrial fibrillation often recurs after restoration of normal sinus rhythm. Antiarrhythmic drugs have been widely used to prevent recurrence. This is an update of a review previously published in 2006, 2012 and 2015.

OBJECTIVES

To determine the effects of long-term treatment with antiarrhythmic drugs on death, stroke, drug adverse effects and recurrence of atrial fibrillation in people who had recovered sinus rhythm after having atrial fibrillation.

SEARCH METHODS

We updated the searches of CENTRAL, MEDLINE and Embase in January 2019, and ClinicalTrials.gov and WHO ICTRP in February 2019. We checked the reference lists of retrieved articles, recent reviews and meta-analyses.

SELECTION CRITERIA

Two authors independently selected randomised controlled trials (RCTs) comparing any antiarrhythmic drug with a control (no treatment, placebo, drugs for rate control) or with another antiarrhythmic drug in adults who had atrial fibrillation and in whom sinus rhythm was restored, spontaneously or by any intervention. We excluded postoperative atrial fibrillation.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed quality and extracted data. We pooled studies, if appropriate, using Mantel-Haenszel risk ratios (RR), with 95% confidence intervals (CI). All results were calculated at one year of follow-up or the nearest time point.

MAIN RESULTS

This update included one new study (100 participants) and excluded one previously included study because of double publication. Finally, we included 59 RCTs comprising 20,981 participants studying quinidine, disopyramide, propafenone, flecainide, metoprolol, amiodarone, dofetilide, dronedarone and sotalol. Overall, mean follow-up was 10.2 months.All-cause mortalityHigh-certainty evidence from five RCTs indicated that treatment with sotalol was associated with a higher all-cause mortality rate compared with placebo or no treatment (RR 2.23, 95% CI 1.03 to 4.81; participants = 1882). The number need to treat for an additional harmful outcome (NNTH) for sotalol was 102 participants treated for one year to have one additional death. Low-certainty evidence from six RCTs suggested that risk of mortality may be higher in people taking quinidine (RR 2.01, 95% CI 0.84 to 4.77; participants = 1646). Moderate-certainty evidence showed increased RR for mortality but with very wide CIs for metoprolol (RR 2.02, 95% CI 0.37 to 11.05, 2 RCTs, participants = 562) and amiodarone (RR 1.66, 95% CI 0.55 to 4.99, 2 RCTs, participants = 444), compared with placebo.We found little or no difference in mortality with dofetilide (RR 0.98, 95% CI 0.76 to 1.27; moderate-certainty evidence) or dronedarone (RR 0.86, 95% CI 0.68 to 1.09; high-certainty evidence) compared to placebo/no treatment. There were few data on mortality for disopyramide, flecainide and propafenone, making impossible a reliable estimation for those drugs.Withdrawals due to adverse eventsAll analysed drugs increased withdrawals due to adverse effects compared to placebo or no treatment (quinidine: RR 1.56, 95% CI 0.87 to 2.78; disopyramide: RR 3.68, 95% CI 0.95 to 14.24; propafenone: RR 1.62, 95% CI 1.07 to 2.46; flecainide: RR 15.41, 95% CI 0.91 to 260.19; metoprolol: RR 3.47, 95% CI 1.48 to 8.15; amiodarone: RR 6.70, 95% CI 1.91 to 23.45; dofetilide: RR 1.77, 95% CI 0.75 to 4.18; dronedarone: RR 1.58, 95% CI 1.34 to 1.85; sotalol: RR 1.95, 95% CI 1.23 to 3.11). Certainty of the evidence for this outcome was low for disopyramide, amiodarone, dofetilide and flecainide; moderate to high for the remaining drugs.ProarrhythmiaVirtually all studied antiarrhythmics showed increased proarrhythmic effects (counting both tachyarrhythmias and bradyarrhythmias attributable to treatment) (quinidine: RR 2.05, 95% CI 0.95 to 4.41; disopyramide: no data; flecainide: RR 4.80, 95% CI 1.30 to 17.77; metoprolol: RR 18.14, 95% CI 2.42 to 135.66; amiodarone: RR 2.22, 95% CI 0.71 to 6.96; dofetilide: RR 5.50, 95% CI 1.33 to 22.76; dronedarone: RR 1.95, 95% CI 0.77 to 4.98; sotalol: RR 3.55, 95% CI 2.16 to 5.83); with the exception of propafenone (RR 1.32, 95% CI 0.39 to 4.47) for which the certainty of evidence was very low and we were uncertain about the effect. Certainty of the evidence for this outcome for the other drugs was moderate to high.StrokeEleven studies reported stroke outcomes with quinidine, disopyramide, flecainide, amiodarone, dronedarone and sotalol. High-certainty evidence from two RCTs suggested that dronedarone may be associated with reduced risk of stroke (RR 0.66, 95% CI 0.47 to 0.95; participants = 5872). This result is attributed to one study dominating the meta-analysis and has yet to be reproduced in other studies. There was no apparent effect on stroke rates with the other antiarrhythmics.Recurrence of atrial fibrillationModerate- to high-certainty evidence, with the exception of disopyramide which was low-certainty evidence, showed that all analysed drugs, including metoprolol, reduced recurrence of atrial fibrillation (quinidine: RR 0.83, 95% CI 0.78 to 0.88; disopyramide: RR 0.77, 95% CI 0.59 to 1.01; propafenone: RR 0.67, 95% CI 0.61 to 0.74; flecainide: RR 0.65, 95% CI 0.55 to 0.77; metoprolol: RR 0.83 95% CI 0.68 to 1.02; amiodarone: RR 0.52, 95% CI 0.46 to 0.58; dofetilide: RR 0.72, 95% CI 0.61 to 0.85; dronedarone: RR 0.85, 95% CI 0.80 to 0.91; sotalol: RR 0.83, 95% CI 0.80 to 0.87). Despite this reduction, atrial fibrillation still recurred in 43% to 67% of people treated with antiarrhythmics.

AUTHORS' CONCLUSIONS

There is high-certainty evidence of increased mortality associated with sotalol treatment, and low-certainty evidence suggesting increased mortality with quinidine, when used for maintaining sinus rhythm in people with atrial fibrillation. We found few data on mortality in people taking disopyramide, flecainide and propafenone, so it was not possible to make a reliable estimation of the mortality risk for these drugs. However, we did find moderate-certainty evidence of marked increases in proarrhythmia and adverse effects with flecainide.Overall, there is evidence showing that antiarrhythmic drugs increase adverse events, increase proarrhythmic events and some antiarrhythmics may increase mortality. Conversely, although they reduce recurrences of atrial fibrillation, there is no evidence of any benefit on other clinical outcomes, compared with placebo or no treatment.

2018 Korean Guideline of Atrial Fibrillation Management

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia in the general population. The Korean Heart Rhythm Society organized a Korean AF Management Guideline Committee and analyzed all available studies regarding the management of AF, including studies on Korean patients. This guideline is based on recent data of the Korean population and the recent guidelines of the European Society of Cardiology, European Association for Cardio-Thoracic Surgery, American Heart Association, and Asia Pacific Heart Rhythm Society. Expert consensus or guidelines for the optimal management of Korean patients with AF were achieved after a systematic review with intensive discussion. This article provides general principles for appropriate risk stratification and selection of anticoagulation therapy in Korean patients with AF. This guideline deals with optimal stroke prevention, screening, rate and rhythm control, risk factor management, and integrated management of AF.

A review of factors associated with maintenance of sinus rhythm after elective electrical cardioversion for atrial fibrillation

Atrial fibrillation is the most common heart-rhythm disorder, affecting about 1.5% to 2% of the population with an increased risk of mortality and morbidity due to stroke, thromboembolism, and heart failure. If the conversion back to sinus rhythm does not happen spontaneously, pharmacological or electrical cardioversion (ECV) is the next available treatment options for some patients. However, the long-term success following ECV is variable. This review describes the factors that are associated with maintenance of sinus rhythm following ECV and proposes a clinical strategy based on the available evidence.

Antiarrhythmics for maintaining sinus rhythm after cardioversion of atrial fibrillation

BACKGROUND

Atrial fibrillation is the most frequent sustained arrhythmia. Atrial fibrillation frequently recurs 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. This is an update of a review previously published in 2008 and 2012.

OBJECTIVES

To determine in patients who have recovered sinus rhythm after having atrial fibrillation, the effects of long-term treatment with antiarrhythmic drugs on death, stroke, embolism, drug adverse effects and recurrence of atrial fibrillation.

SEARCH METHODS

We updated the searches of CENTRAL in The Cochrane Library (2013, Issue 12 of 12), MEDLINE (to January 2014) and EMBASE (to January 2014). The reference lists of retrieved articles, recent reviews and meta-analyses were checked.

SELECTION CRITERIA

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

DATA COLLECTION AND ANALYSIS

Two authors 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 three new studies, with 534 patients, were included making a total of 59 included studies comprising 21,305 patients. All included studies were randomised controlled trials. Allocation concealment was adequate in 17 trials, it was unclear in the remaining 42 trials. Risk of bias was assessed in all domains only in the trials included in this update.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 treat to harm (NNTH) 109, 95% CI 34 to 4985) and sotalol (OR 2.23, 95% CI 1.1 to 4.50, NNTH 169, 95% CI 60 to 2068) were associated with increased all-cause mortality. Other antiarrhythmics did not seem to modify mortality, but our data could be underpowered to detect mild increases in mortality for several of the drugs studied.Several class IA (disopyramide, quinidine), IC (flecainide, propafenone) and III (amiodarone, dofetilide, dronedarone, sotalol) drugs significantly reduced recurrence of atrial fibrillation (OR 0.19 to 0.70, number needed to treat to beneft (NNTB) 3 to 16). Beta-blockers (metoprolol) also significantly reduced atrial fibrillation recurrences (OR 0.62, 95% CI 0.44 to 0.88, NNTB 9).All analysed drugs increased withdrawals due to adverse affects and all but amiodarone, dronedarone and propafenone increased pro-arrhythmia. Only 11 trials reported data on stroke. None of them found any significant difference with the exception of a single trial than found less strokes in the group treated with dronedarone compared to placebo. This finding was not confirmed in others studies on dronedarone.We could not analyse heart failure and use of anticoagulation because few original studies reported on these measures.

AUTHORS' CONCLUSIONS

Several class IA, IC and III drugs, as well as class II drugs (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, embolism, heart failure) remain to be established.

Risk factors for atrial fibrillation recurrence: a literature review

Atrial fibrillation is the most common arrhythmia managed in clinical practice and it is associated with an increased risk of mortality, stroke and peripheral embolism. Unfortunately, the incidence of atrial fibrillation recurrence ranges from 40 to 50%, despite the attempts of electrical cardioversion and the administration of antiarrhythmic drugs. In this review, the literature data about predictors of atrial fibrillation recurrence are highlighted, with special regard to clinical, therapeutic, biochemical, ECG and echocardiographic parameters after electrical cardioversion and ablation. Identifying predictors of success in maintaining sinus rhythm after cardioversion or ablation may allow a better selection of patients to undergo these procedures. The aim is to reduce healthcare costs and avoid exposing patients to unnecessary procedures and related complications. Recurrent atrial fibrillation depends on a combination of several parameters and each patient should be individually assessed for such a risk of recurrence.

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.

Antiarrhythmics for maintaining sinus rhythm after cardioversion of atrial fibrillation

BACKGROUND

Atrial fibrillation (AF) is the most frequent sustained arrhythmia. After restoration of normal sinus rhythm, the recurrence rate of AF is high. 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. If several antiarrhythmics were effective our secondary aim was to compare them.

SEARCH STRATEGY

The Cochrane Central Register of Controlled Trials (CENTRAL) on The Cochrane Libary (Issue 2, 2005), MEDLINE (1950 to May 2005) and EMBASE (1966 to May 2005) were searched. The reference lists of retrieved articles, recent reviews and meta-analyses were checked. No language restrictions were applied.

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, on an intention-to-treat basis. Disagreements were resolved by discussion. Studies were pooled, if appropriate, using Peto odds ratio (OR).

MAIN RESULTS

45 studies met inclusion criteria, comprising 12,559 patients. All results were calculated at 1 year of follow-up. Class IA drugs (disopyramide, quinidine) were associated with increased mortality compared with controls (OR 2.39, 95% confidence interval (CI) 1.03 to 5.59, P = 0.04, number needed to harm (NNH) 109, 95% CI 34 to 4985). Other antiarrhythmics did not 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 0.60, number needed to treat 2 to 9), but all increased withdrawals due to adverse affects (NNH 17 to 36) and all but amiodarone and propafenone increased pro-arrhythmia (NNH 17 to 119).

AUTHORS' CONCLUSIONS

Several class IA, IC and III drugs are effective in maintaining sinus rhythm but increase adverse events, including pro-arrhythmia, and disopyramide and quinidine are associated with increased mortality. Any benefit on clinically relevant outcomes (embolisms, heart failure, mortality) remains to be established.

Impact of informed consent requirements on cardiac arrest research in the United States: exception from consent or from research?

INTRODUCTION

Research in patients with life-threatening illness such as cardiac arrest is challenging since they can not consent. The Food and Drug Administration addressed research under emergency conditions by publishing new criteria for exception from informed consent in 1996. We systematically reviewed randomized trials over a 10-year period to assess the impact of these regulations.

METHODS

Case-control study of published trials for cardiac arrest (cases) and atrial fibrillation (controls.) Studies were identified by using structured searches of MEDLINE and EMBASE from 1992 to 2002. Included were studies using random allocation in humans with cardiac arrest or atrial fibrillation prior to enrollment. Excluded were duplicate publications. Number of American trials, foreign trials and proportion of trials of American origin were compared by using regression analysis. Changes in cardiac arrest versus atrial fibrillation trials were calculated as risk differences.

RESULTS

Of 4982 identified cardiac arrest studies, 57 (1.1%) were randomized trials. The number of American cardiac arrest trials decreased by 15% (95% CI: 8, 22%) annually (P = 0.05). The proportion of cardiac arrest trials of American origin decreased by 16% (95% CI: 10, 22%) annually (P = 0.006). Of 5596 identified atrial fibrillation studies, 197 trials (3.5%) were randomized trials. The risk difference between cardiac arrest versus atrial fibrillation trials being of American origin decreased significantly (annual difference -5.8% (95% CI: -10, -0.1%), P = 0.03).

INTERPRETATION

Fewer American cardiac arrest trials were published during the last decade, when federal consent requirements changed. Regulatory requirements for clinical trials may inhibit improvements in care and threaten public health.

Investigation of the optimal treatment strategy for atrial fibrillation in Japan

The Japanese Rhythm Management Trial for Atrial Fibrillation (J-RHYTHM study) is a randomized comparative evaluation of rate control and rhythm control, both combined with antithrombotic therapy, as therapeutic strategies for the treatment of atrial fibrillation (AF). This study differs from the earlier AFFIRM and RACE studies in that it has a composite primary end-point representing mortality and also physical/psychological disablement (total mortality, symptomatic cerebral infarction, systemic embolism, major bleeding, hospitalization for heart failure requiring intravenous administration of diuretics, and patient disablement). Patients' will to change the therapeutic strategy to the other is also considered as an end-point representing disablement under the assigned strategy. The secondary end-point includes quality of life scores and the efficacy and safety of drugs used in treating AF. The J-RHYTHM study emphasizes patient-reported experience and perception of AF-specific disablement, and the safety of antiarrhythmics available in Japan; it will follow 2600 patients treated at more than 150 sites in Japan for a 3-year period.