Inclusion Criteria:  Adult patients (18-90 years of age) undergoing redo ablation procedures for paroxysmal AF regardless of the systems or energy sources used during the pre-study ablation procedure(s). Paroxysmal AF: defined as AF terminating within 7 days of onset either spontaneously or with electrical or medical cardioversion.  Exclusion Criteria:  Persistent AF Prior cardiac surgery Patients with only AFL or AT as the documented recurrent arrhythmia after the pre-study AF ablation(s).