Catheter ablation
Procedures were performed under sedation or general anaesthesia, according to each institution’s protocol. Venous access was obtained via the femoral vein, with use of vascular ultrasound at operator’s discretion. In the absence of patent foramen ovale, a single or dual transseptal puncture was performed under fluoroscopic guidance. Transesophageal echocardiography (TOE) was used based on operator preference. Patients received intravenous heparin to maintain an activated clotting time of 300–350 seconds. Pulmonary vein isolation was the main procedural end-point, and was performed as a first step in all procedures. Additional substrate modification was at operator’s discretion. Patients were evaluated before discharge, at 30-days, and 3-months after the procedure, additional visits and further testing were allowed in case of symptoms.