Clinical Question

Do antiarrhythmic agents (class I and III) prevent the recurrence of atrial fibrillation postablation?

Evidence-Based Answer

Compared with placebo, class I and III antiar-rhythmic agents reduce the recurrence of atrial fibrillation after catheter ablation at three to six months postablation (absolute risk reduction = 6.8%; 95% CI, 3.2% to 10%; number needed to treat [NNT] = 15). There are no differences in all-cause mortality, thromboembolic events, or myocardial infarction during the three- to six-month postablation period in patients using class I and III antiarrhythmics compared with those in the control group.¹ (Strength of Recommendation: C, disease-oriented evidence.)

Discussion

Atrial fibrillation is the primary diagnosis in more than 454,000 hospitalized patients each year; it contributes to approximately 158,000 deaths annually.² In 2019, updates to the American Heart Association guidelines indicated that atrial fibrillation ablation is reasonable in patients with symptomatic atrial fibrillation and heart failure with reduced left ventricular ejection fraction to lower the mortality rate and hospitalizations.³ Recurrent atrial tachyarrhythmias following catheter ablation for atrial fibrillation are a common problem, with an incidence of at least 20% to 40%.⁴ Although antiarrhythmic drugs, particularly class I and III medications, are used to maintain sinus rhythm, it is unclear whether they reduce the risk of recurrent atrial tachyarrhythmias. The authors of this Cochrane review sought to determine whether class I and III antiarrhythmic drugs prevent postablation recurrence of atrial tachyarrhythmias and whether the use of these medications is associated with an increased risk.

This review included nine randomized controlled trials from six countries in North America, Europe, and Asia. The 3,269 participants were assigned to class I or III antiarrhythmics (or both) vs. placebo or control with standard treatment to maintain sinus rhythm. Class I antiarrhythmics were flecainide or propafenone, and class III medications were amiodarone, dofetilide, drone-darone (Multaq), and sotalol. Patients were 18 years and older of either sex, with an average age of 59 years. Among the participants, 72.9% had paroxysmal atrial fibrillation, and 27.4% were in persistent atrial fibrillation. The doses of antiarrhythmics used were not reported in all trials. The follow-up duration of these studies ranged from 13 to 48 months. Primary outcomes were recurrence of atrial tachyarrhythmias (atrial fibrillation, atrial flutter, or atrial tachycardia lasting longer than 30 seconds) and occurrence of adverse events including thromboembolic events, myocardial infarction, a new diagnosis of heart failure, and a need for one or more hospitalizations for atrial tachyarrhythmia. Secondary outcomes were all-cause mortality and needing one or more repeat ablations.

The follow-up period of interest for recurrence of atrial tachyarrhythmias was three to six months or more because arrhythmias are more common while the body is recovering from ablation during the zero- to three-month postablation period.

Antiarrhythmic drugs reduced the recurrence of atrial tachyarrhythmias by 6.8% compared with placebo (95% CI, 3.2% to 10%; NNT = 15) at three to six months or more postablation, based on five trials of 2,591 participants. Data were collected via electrocardiographic event recorders, transtelephonic electrocardiography, ambulatory electrocardiographic monitoring, or 12-lead electrocardiography, representing disease-oriented evidence. Most trials did not specify the reported duration of atrial tachyarrhythmia recurrence.

Three trials with 448 participants noted a reduction in hospitalizations between zero and three months postablation (NNT to prevent one hospitalization = 7; 95% CI, 5 to 10; moderate-certainty evidence). The adverse outcomes of thromboembolism, myocardial infarction, and all-cause mortality showed no difference among groups but were based on low- to very low-certainty evidence.

Previous meta-analyses did not assess the recurrence of atrial tachyarrhythmias after catheter ablation during the three to six months postablation.

The latest guidance from the American Heart Association/American College of Cardiology/Heart Rhythm Society and the National Institute for Health and Care Excellence does not recommend the use of antiarrhythmic drugs in patients after ablation.^3,5

The practice recommendations in this activity are available at https://www.cochrane.org/CD013765.