First-Line Ablation More Effective than Antiarrhythmic Drugs for Atrial Fibrillation

Jason Andrade, MD

Data from the EARLY-AF trial suggests first-line therapy with ablation could help maintain sinus rhythm better than traditional antiarrhythmic agents for patients with atrial fibrillation (AF).

Results of the randomized trial indicate first-line ablation was linked to significant reductions arrhythmia outcomes including total AF burden and days with AF, suggesting initial treatment with ablation could be a more effective approach than first-line treatment with antiarrhythmic drugs, which is the current recommendation in contemporary guidelines.

“In this randomized trial involving patients with untreated paroxysmal atrial fibrillation, catheter cryoballoon ablation resulted in a significantly lower rate of recurrence of atrial tachyarrhythmia, as assessed by continuous cardiac rhythm monitoring, than antiarrhythmic drug therapy,” wrote study investigators.

To compare first-line approaches with cryoablation versus antiarrhythmic drugs, EARLY-AF was designed as a multicenter, open-label, randomized trial with blinded endpoint adjudication and conducted across 18 centers in Canada. Enrolling patients 18 and older with symptomatic AF and at least one episode of AF within 24 months before randomization, investigators enrolled a cohort of 303 patients for inclusion in their trial.

Patients were excluded from the study if they had a history of regular use of a class I or class III antiarrhythmic drug. Patients included in the study were randomized in 1:1 ratio to an initial strategy of catheter cry-balloon ablation or antiarrhythmic drug therapy. All patients in the study underwent insertion of an implantable cardiac monitor following enrollment with the goal of using this data to quantify AF burden.

The primary end point of the study was the first documented recurrence of any atrial tachyarrhythmia, between 91 and 365 days after catheter ablation or the initiation of an antiarrhythmic drug. Secondary endpoints included free from symptomatic arrhythmia, AF burden, and quality of life. The total follow-up period lasted 12 months.

Upon analysis, investigators found first-line ablation was associated with a 52% reduction in the recurrence of atrial tachyarrhythmia at 1 year—with events occurring among 66 of 154 patients randomized to undergo ablation and among 101 of 149 patients randomized to antiarrhythmic drug (HR, 0.48; 95% CI, 0.35-0.66; P <.001). Further analysis indicated symptomatic atrial tachyarrhythmia had recurred in 11% of patients randomized to ablation and 26.2% randomized to arrhythmic drug s (HR, 0.39; 95% CI, 0.22-0.68).

The analysis also suggested patients in the ablation group had a lower median percentage of time in atrial fibrillation than those receiving antiarrhythmic drugs (ablation: 0%, IQR, 0-0.08; antiarrhythmic drugs: 0.13%, IQR, 0-1.60). The trial’s safety analysis indicated serious adverse events occurred in 3.2% of those who underwent ablation compared to 4.0% of those who received antiarrhythmic drugs.

During his presentation at the American Heart Association Scientific Sessions 2020, Jason Andrade, MD, pointed out first-line ablation was associated with significant reductions in time to first recurrence of any atrial fibrillation, time to first recurrence of symptomatic atrial fibrillation, total AF burden, and days with AF.

This study, “Cryoablation or Drug Therapy for Initial Treatment of Atrial Fibrillation” was presented at AHA 2020 and simultaneously published in the New England Journal of Medicine.