Background: Superior vena cava (SVC) has been considered a specific trigger in atrial fibrillation (AF) development. Cryoballoon SVC isolation seems feasible and safe, and has never been compared in addition to pulmonary vein isolation (PVI) to PVI alone. Methods and results: A unicenter randomized trial, comparing two ablation procedures is proposed. Cryoballoon SVC isolation in addition to PVI is compared to PVI alone in paroxysmal or non-longstanding persistent AF patients. Patients from 18-80 years old are included. Patients are excluded if there is a previous AF ablation procedure, transvenous pacemaker or defibrillator (ICD) implanted, severe mitral valve disease, left atrium (LA) anteroposterior diameter > 55mm or LA indexed volume > 48ml/m2 in an echocardiogram performed in the last year, left ventricular ejection fraction (LVEF) < 35%, hypertrophic or restrictive cardiomyopathy. All patients are provided an Alivecor® Kardia Mobile device to record an electrocardiogram (ECG) every day and in case of clinical symptoms to monitor recurrences. The primary efficacy end point is defined as any AF/atrial flutter/atrial tachycardia recurrence, with a minimal duration of 30 seconds, registered with surface ECG, Holter ECG or Kardia mobile registry during a 12 months follow up period. Conclusion: Our study will provide data about the efficacy of SVC isolation in addition to PVI compared to PVI alone in a randomized way, in paroxysmal and non long standing persistent AF patients.