Patients with persistent or long-standing persistent atrial fibrillation will be enrolled in this multi-center, randomized, prospective, single-blinded study. All patients are required to be in atrial fibrillation (AF) on the day of the ablation procedure. After ablation (isolation) of the pulmonary veins (PVI) is complete, and while still in the electrophysiology lab, all patients are randomized to either PVI, alone [Group 1] or the combination of PVI plus ablation of the posterior left atrial wall (PLAW) [Group 2]. For those patients randomized to PVI, their ablation procedure is complete at this time. For those patients randomized to PVI plus PLAW, they will have the additional ablation to the posterior left atrial wall performed.
All study patients have the same follow-up after their ablation procedure: clinic visits at 3, 6, and 13 months; a heart event monitor is worn for 7-14 days before these visits. An echocardiogram is done at 4-6 months after the ablation procedure. Blood thinners are usually recommended for three months after the ablation procedure and then the need for continued use of blood thinners will be based on individual patient's medical history, stroke risk and the judgement of their study doctor. Information about patient's medical history, heart arrhythmias, and atrial fibrillation will be collected during the study. This information will be analyzed as part of the study.