Subject Population: Eligible patients are patients with paroxysmal high-burden AF who are planned for a 'CLOSE'-guided PV isolation. At the time of procedural planning we will ask the patient his/her consent for (1) implantation of a subcutaneous continuous loop recorder (sCLR), (2) a concise electrophysiological study at the time of PVI, (3) a transthoracic echocardiogram at the time of PVI and (4) collection of data during 3 years. Anti-arrhythmic drug treatment (ADT) and oral anticoagulation (OAC) will be given according the updated 2012 European society of Cardiology (ESC) guidelines on AF (Camm et al, European Heart Journal 2012) and the 2012 Heart rhythm society (HRS)/European Heart Rhythm association/European cardiac arrhythmic society Expert Consensus Statement on catheter and surgical ablation of atrial fibrillation (Calkins et al, Heart Rhythm 2012).