Study design
The INSIDE PVs study (INtra-procedural ultraSound Imaging for DEtermination of atrial wall thickness and acute tissue changes after isolation of the Pulmonary Veins with radiofrequency, cryoballoon or laser balloon energy) was a single-center prospective pilot study. The trial was approved by the Local Ethics Committee, complied with the Declaration of Helsinki and was registered on www.clinicaltrials.gov (Identifier NCT03372798).
Patients scheduled for RF, cryoballoon or laser balloon PVI catheter ablation for symptomatic, drug-refractory paroxysmal atrial fibrillation (AF) were eligible for the trial. All AF ablations were performed in a standard fashion, as described in the supplementary section.