Safety and efficacy of second-generation versus first-generation cryoballoons for treatment of atrial fibrillation: a meta-analysis of current evidence.

BACKGROUND: The newer second-generation cryoballoons (CB-2 or Arc-Adv-CB) have been shown to achieve significantly lower temperature and faster pulmonary vein isolation (PVI) time in comparison with first-generation cryoballoons (CB-1 or Arc-CB). To test the premise that second-generation cryoballoons can improve clinical outcomes in comparison to first-generation cryoballoons in terms of safety and efficacy, we pooled data for systemic review and meta-analyses from all available literature comparing their clinical performance.

METHODS: The Cochrane Library, PubMed, Google Scholar, and studies presented at various meetings were searched for any published literature comparing safety and efficacy of the second-generation cryoballoons (Arctic Front Advance cryoballoons) with first-generation cryoballoons (Arctic Front Cryoballoons). A total of ten published studies, with 2310 patients, were included in this meta-analysis with 957 patients in second-generation cryoballoon group and 1237 patients in first-generation cryoballoon group.

RESULTS: The pooled analysis showed significant superiority of second-generation cryoballoons in terms of less procedure time, less fluoroscopic time, and fewer incidences of arrhythmia recurrences compared to first-generation cryoballoons at the cost of higher incidence of persistent and transient phrenic nerve palsy. The differences in the rate of pericardial effusion and incidence of access site complications were not statistically significant.

CONCLUSIONS: Second-generation cryoballoons are associated with a shorter procedure time and fluoroscopy time, along with lower arrhythmia recurrence rates, reflecting higher procedure efficacy when compared to first-generation cryoballoons. However, they are also associated with a higher incidence of transient and persistent phrenic nerve palsies with a non-significant difference in rates of access site complications and pericardial effusion.