This study examines non-inferiority of pulmonary vein isolation (PVI) for persistent atrial fibrillation (AF) to extensive ablation; and reveals the effect of the presence or origin of AF trigger on outcomes of catheter ablation.

Study design The EARNEST-PVI trial is a prospective, multicenter, randomized, open-label non-inferiority trial in which patients with persistent AF will undergo ablation. After providing written informed consent at each hospital, patients who are eligible for the trial will be randomized to either PVI alone or PVI plus additional ablation. Left atrial dimensions will be the only adjustment factor considered in dynamic allocation to avoid bias. Patients randomized to the PVI alone group will be treated with PVI, while patients randomized to the PVI plus additional ablation group will receive additional complex fractionated atrial electrogram or linear ablation after PVI. Ablation for AF triggers from non-PV foci, the cavotricuspid isthmus, clinical coexisting tachyarrhythmia such as atrial flutter (AFL), atrial tachycardia (AT), and supraventricular tachycardia will be allowed in both groups. Patients will be followed up 1, 3, 6, 9, and 12 months after the procedure. The primary endpoint of the study is the recurrence of AF documented by scheduled or symptom-driven ECG during 1 year after the procedure. "Recurrence of AF" is defined as the documentation of any atrial arrhythmia including AF, AFL, and/or AT lasting ≥ 30 seconds by ECG or other appropriate tests. The sample size and randomization are specified based on the concept of non-inferiority to achieve the primary objective. The recurrence rate of AF was assumed to be 40% in both groups and a non-inferiority margin of 10% was calculated by referring to the previous studies. Therefore, a sample size of 256 subjects in each group is required with a power of 80% and significance level of 5% considering some dropouts. The statistical evaluation will be carried out according to the intention-to-treat principle.

Inclusion Criteria:

• Patients undergoing a first-time ablation procedure for persistent AF

Exclusion Criteria:

• Patients with long-standing persistent AF lasting ≥ 5 years
• Patients with left atrial dimension ≥ 50 mm by 2-dimensional echocardiography
• Patients with valvular AF (defined as the presence of mitral or aortic stenosis or regurgitation with a history of rheumatic fever or implantation of artificial heart valves)
• Patients who underwent prior cardiac surgery
• Patients receiving hemodialysis
• Patients with heart failure (left ventricular ejection fraction < 30% and NYHA class ≥ III)
• Patients receiving antiarrhythmic agents before the ablation procedure (within 60 days for amiodarone, or 5 half-lives for other drugs)
• Patients who are not considered to be suitable candidates by the attending physician