This study evaluates if the exclusion of left atrial low voltage areas / scars by ablation lines in addition to pulmonary vein isolation may improve the outcome in patients with persistent atrial fibrillation in comparison to stand alone pulmonary vein isolation.

This is a prospective, randomized multi center study comparing two catheter ablation strategies (pulmonary vein isolation (PVI) versus PVI plus low voltage areas (LVA) guided for ablation in patients with symptomatic persistent and long standing persistent atrial fibrillation (AF) who were unresponsive to at least one Class I or III antiarrhythmic agents, or it is the patient´s decision to receive ablation as first line therapy. Patients with documented persistent AF who are eligible for participation in the study, and gave a written informed consent, will be randomized between two groups prior to the procedure: PVI and PVI+LVAs guided radiofrequency catheter ablation.

All the patients will receive a high density voltage map in sinus rhythm (SR). All the patients will receive circumferential PVI. If LVAs are present, Patients randomized to the PVI+LVA group will get additional linear ablation lines to exclude these areas from normal voltage atrial myocardium. The patients will be followed for 12 months.

Inclusion Criteria:

• Symptomatic patients with persistent AF documented by 12 lead ECGs (Persistent AF is defined as an AF episode which lasts longer than 7 days, Persistent AF which lasted longer than 12 months will be defined as long standing persistent AF.)
• Age 18 - 80 years, both genders
• Patient is willing to participate in the study (signed written informed consent)
• Patient is willing and available to perform all follow ups.

Exclusion Criteria:

• Atrial fibrillation due to reversible causes
• Any contraindication for AF ablation
• Contraindications to anticoagulation
• CVA/TIA in the past 6 months
• Previous left atrial catheter ablation