Safety and efficacy of persistent atrial fibrillation ablation using the second-generation cryoballoon

Background: The second-generation cryoballoon (CB) is increasingly used for treatment of persistent atrial fibrillation (AF). Data regarding the clinical outcome and mechanism of arrhythmia recurrence following persistent AF ablation using CB is sparse. In this study, we aimed to assess the efficacy of CB and mechanisms of atrial tachyarrhythmia (ATA) recurrence in patients with persistent AF. Methods and results: A total of 133 patients (66 ± 10 years, 60% male) with symptomatic persistent AF, who were scheduled for PVI using the second-generation CB were enrolled. Follow-up included 24 h Holter recording at 3, 6 and 12 months. Any documented episode of ATA lasting more than 30 s was considered as a recurrent arrhythmic event. All targeted veins were isolated (100%). Phrenic nerve palsy with recovery during follow-up occurred in six patients (4.5%), no patient experienced tamponade or a cerebrovascular event. During 12.6 ± 5.4 months of follow-up, 89/133 (67%) patients were free of ATA recurrences. Multivariable analysis revealed recurrence in the blanking period (HR 11.46, 0.95 CI 3.92–33.49, p < 0.001), presence of cardiomyopathy (HR 2.75, 0.95 CI 1.09–6.96, p = 0.032) and PV abnormality (HR 3.56, 0.95 CI 1.21–10.43, p = 0.021) as predictors for late recurrence. Conclusion: In patients with persistent AF, second-generation cryoballoon use is associated with an excellent safety profile and favorable outcomes. Arrhythmia recurrence during the blanking period, presence of cardiomyopathy and PV abnormality were independent predictors of long-term AF recurrence.