New Minimally Invasive and Tailor-Made Strategy for Cryoballoon Ablation in Patients With Paroxysmal Atrial
Takayuki Nakano1, Kazuyoshi Suenari2, Akira Okada2
1Department of Cardiology, Hiroshima City Hiroshima Citizens Hospital, Hiroshima, Japan; Department of Cardiovascular Medicine, Hiroshima University Graduate School of Biomedical and Health Sciences, Hiroshima, Japan.
Background:
The optimal dosage for cryoballoon ablation (CBA) of atrial fibrillation (AF) is still unknown.
Objective:
This study aimed to evaluate the clinical implications of a reduction in the freezing duration to <180 seconds during CBA guided by the time to the target temperature.
Methods:
This study enrolled 325 consecutive paroxysmal AF patients who underwent CBA. It was a retrospective observational study in a single centre. It compared 164 patients who underwent a tailor-made CBA procedure (group T) with 161 who had a standard CBA procedure (group S). In group T, the freezing duration was reduced to 150 seconds when the temperature reached ≤ -40 °C within 40 seconds. Furthermore, it was reduced to 120 seconds when it reached ≤ -50 °C within 60 seconds. In the other patients, the freezing duration was 180 seconds, except for excessive freezing of ≤ -60 °C and/or emergent situations while monitoring the oesophageal temperature, and for phrenic nerve injury, as in group S.
Results:
In group T, 89 patients (83%) underwent CBA with a reduction in the freezing duration. The total freezing time for each pulmonary vein was significantly shorter in group T than group S, and the total procedure time in group T decreased by an average of 4 minutes compared with group S. The rate of requiring additional radio frequency ablation following the CBA was significantly lower in group T than group S. The AF-free survival rate during the follow-up period (median, 366 days) was similar between the two groups.
Conclusion:
The safety and efficacy of the new CBA strategy were non-inferior to the standard procedure.
