Inclusion Criteria:  Patients aged 20 to 80 years with a proper indication for AFCA Left atrium size < 55 mm AF recurred during the administration of antiarrhythmic drugs or that antiarrhythmic drugs intolerable patients Patients eligible for anticoagulant therapy (to prevent thromboembolic events)  Exclusion Criteria:  AF associated with severe cardiac anomalies or structural heart disease with hemodynamic influence Patients who have difficulty in CT imaging using a contrast medium Patients with a previous history of AFCA or other cardiac surgery Patients with active internal bleeding Inappropriate anticoagulant therapy valvular atrial fibrillation (mitral stenosis>grade 2, mechanical valve) Serious comorbidities Patients expected to survive less than 1 year People with drug or alcohol addiction Those who cannot read the consent form (illiterate, foreigners, etc.) Patients who are judged unsuitable for participation in clinical research by the judgment of other investigators