Using Cryoballoon Ablation as Initial Treatment for Persistent Atrial Fibrillation

Inclusion Criteria: * Documentation of symptomatic persistent AF: Defined as having a continuous episode lasting longer than 7 days but less than 1 year documented by consecutive ECG recordings OR Defined as having a continuous episode lasting longer than 7 days but less than 1 year documented by an ECG recording and one doctor note indicating patient had symptoms consistent with AF * Age 18 -75 years old * Structurally normal heart with LVEF ≥50%, interventricular septum thickness ≤ 12 mm, and left atrial diameter \<46 mm (short axis) as obtained by transthoracic echocardiography. • * Normal ECG parameters when measured in sinus rhythm (QRS width ≤120 ms in a 12-channel surface ECG, QTc interval \<440 ms, and PQ interval ≤210 ms). Exclusion Criteria: * History of AF treatment with class I or III antiarrhythmic drug, including sotalol, with the intention to prevent an AF recurrence. However, patients pretreated with above AAD for less than 7 days with the intention to convert an AF episode are allowed. * left atrial ablation or surgical procedure (including left atrial appendage closures) * Presence or likely implant of a permanent pacemaker, biventricular pacemaker, loop recorder, or any type of implantable cardiac defibrillator (with or without biventricular pacing function) within 12 months * Presence of any pulmonary vein stents * Presence of any pre-existing pulmonary vein stenosis * Pre-existing hemidiaphragmatic paralysis * Presence of any cardiac valve prosthesis * +3 and +4 mitral valve regurgitation or stenosis * Any cardiac surgery, myocardial infarction, percutaneous coronary intervention (PCI) / percutaneous transluminal coronary angioplasty (PTCA) or coronary artery stenting which occurred during the 3 month interval preceding e consent date * Unstable angina * New York Heart Association (NYHA) Class II, III or IV congestive heart failure * Primary pulmonary hypertension * Rheumatic heart disease * Thrombocytosis, thrombocytopenia * Any condition contraindicating chronic anticoagulation * Active systemic infection * Hypertrophic cardiomyopathy * Cryoglobulinemia * Uncontrolled hyperthyroidism * Any cerebral ischemic event (strokes or transient ischemic attacks (TIAs)) which occurred during the 6 month interval preceding the consent date * Any woman known to be pregnant or breastfeeding. * Life expectancy less than one year * Current or anticipated participation in any other clinical trial of a drug, device or biologic during the duration of the study not pre-approved by Medtronic * Active intracardiac thrombus * Known drug or alcohol dependency * Unwilling or unable to comply fully with study procedures and follow-up * Significant Chronic Kidney Disease-estimated Glomerular Filtration Rate(CKD-eGFR) \<30umol/L