Safety and feasibility of electrical isolation of the superior vena cava in addition to pulmonary vein ablation for paroxysmal atrial fibrillation using the cryoballoon: lessons from a prospective study

PURPOSE: The purpose of this study was to evaluate the feasibility and safety of superior vena cava (SVC) isolation in addition to standard pulmonary vein isolation (PVI) using the second-generation cryoballoon (CB) in patients with paroxysmal atrial fibrillation.

METHODS: Thirty-seven consecutive patients that underwent CB ablation for paroxysmal atrial fibrillation (PAF) were prospectively enrolled in our study. After PVI the SVC was mapped for potentials. If the SVC exhibited electrical activity, isolation was achieved performing a single 180-s balloon application.

RESULTS: Regarding SVC isolation, 180-s freeze in the SVC could be completed in 32 (86.4%) patients, and 5 patients had at least 120 s of freezing application (13.5%). Real-time recording during SVC isolation was observed in 30 (81.0%) patients. The mean time to isolation was 36.9 ± 28.7 s and the temperature at isolation was - 33 (- 15 to - 40) °C. No cases developed persistent phrenic nerve palsy (PNP) or any other complication.

CONCLUSIONS: Superior vena cava isolation proved to be safe and feasible with the second generation cryoballoon in a prospective series of patients affected by PAF.