One-year clinical outcome after pulmonary vein isolation using the second-generation 28-mm cryoballoon.

Background: The use of second-generation cryoballoon for pulmonary vein isolation in patients with paroxysmal atrial fibrillation has demonstrated encouraging acute and mid-term results. Long-term outcome data are not yet available.

Methods And Results: Fifty patients (18 women; mean age, 61±11 years; mean left atrial diameter, 43±5 mm) with paroxysmal (36 of 50 patients; 72%) or short-standing (<3-month duration) persistent atrial fibrillation (14 of 50 patients; 28%) underwent cryoballoon-based pulmonary vein isolation. Freeze cycle duration was 240 seconds. After successful pulmonary vein isolation, a bonus freeze was applied. Follow-up was based on outpatient clinic visits at 3, 6, and 12 months including Holter-ECGs and telephonic interviews. Recurrence was defined as a symptomatic or documented arrhythmia episode>30 seconds excluding a 3-month blanking period. A total of 192 pulmonary veins were identified, and 191 of 192 (99%) pulmonary veins were successfully isolated. Phrenic nerve palsy occurred in 1 of 50 (2%) patients. Follow-up was available for 49 of 50 (98%) patients with a mean follow-up duration of 440±39 days. Thirty-nine of 49 (80%) patients remained in stable sinus rhythm. Of 8 of 10 patients with arrhythmia recurrence, a second procedure using radiofrequency ablation demonstrated left atrial to pulmonary vein reconduction.

Conclusions: The use of second-generation 28-mm cryoballoon for pulmonary vein isolation results in an 80% 1-year success rate.