Impact of an additional right pulmonary vein on second-generation cryoballoon ablation for atrial fibrillation: a propensity matched score study.

Cryoballoon (CB) technology in the context of anatomical pulmonary vein (PV) variants might hypothetically hamper successful PV isolation (PVI). Our aim was to assess the impact of a right middle PV (RMPV) in the setting of second-generation cryoballoon (CB advance-CB-A), on procedural parameters and on mid-term follow-up. Consecutive patients with AF presenting RMPV (RMPV+) at the pre-procedural computed tomography who underwent PVI by CB-A were enrolled. Comparison with propensity score-matched patients without RMPV (RMPV-) was performed. Acute procedural parameters and clinical follow-up were assessed. A total of 240 patients (80 RMPV+) were included in the analysis. Twelve of 80 (15%) RMPV+ patients underwent a direct cryo-application in this variant and accomplished the isolation without phrenic nerve palsy, whereas in 25 of 80 (31%) RMPV+ patients, the RMPVs were not targeted directly nor indirectly (by co-occlusion during application at a major PV). At a median follow-up of 17.3 [interquartile range 11.3-26.5] months, there was no significant difference in AF-free survival between RMPV+ and RMPV- patients (78.8 vs 78.1%, P = 1.00), and the recurrence of atrial arrhythmias among patients with versus without an intentional or indirect cryo-application to the RMPV was not different (22 vs 20%, P = 1.00). Mid-term outcome after CB-A ablation did not differ between RMPV+ and RMPV- patients. Within RMPV+ patients, outcome was similar between those with versus without a cryo-application (either direct or indirect) to the additional vein.