Inclusion Criteria:  Subject has been diagnosed with persistent AF. Subject is ≥ 18 years of age or minimum age as required by local regulations. Planned pulmonary vein isolation (PVI) procedure using commercially available Arctic Front™ Cardiac Cryoablation Catheter System. Willing to comply with study requirements and give informed consent (defined as legally effective, documented confirmation of a subject's voluntary agreement to participate in this clinical study) or authorization per institution and geographical requirements.  Exclusion Criteria:  Subject has had a prior atrial ablation (except for cavo-tricuspid isthmus (CTI) ablation for AFL). Subject is enrolled in a concurrent study that has not been approved for concurrent enrollment by the global study manager. Subject with exclusion criteria required by local law.