text: Novel usage of the cryoballoon catheter to achieve large area atrial substrate modification in persistent and long-standing persistent atrial fibrillation.
  The cryoballoon catheter has proven to be both safe and effective when used for pulmonary vein (PV) isolation in patients with paroxysmal atrial fibrillation (AF). More recently, the cryoballoon catheter has demonstrated the ability to create durable, transmural, and large areas of PV ablation. However, persistent and long-standing persistent AF can require additional cardiac substrate modification(s) before a patient is returned to normal sinus rhythm. Yet, no study has reported the techniques necessary to achieve extra-PV lesion sets using the cryoballoon catheter. Cryoballoon ablation was completed in 225 patients with varying degrees of AF disease. In several cases, the balloon was used for more than PV isolation. This study examines the 11 anatomical cardiac locations where extra-PV lesion sets were utilized. This study demonstrates that these extra-PV ablations can be done safely with the balloon catheter (3.6 % total complication rate). The 12-month efficacy (freedom from all atrial arrhythmia) using these techniques was 88 % in 88 patients with paroxysmal AF, 71 % in 75 patients with persistent AF, and 55 % in 62 patients with long-standing persistent AF. While using this protocol, mean procedure time was 2.2 ± 0.6 h, and average fluoroscopy time was 4.2 ± 2.2 min. The cryoballoon catheter can be used to make effective and safe extra-PV lesions. However, these techniques will need to be validated in more multi-center studies with review of complication rates and long-term freedom from AF.