FIRE AND ICE II Trial Pilot

Key Inclusion Criteria * Documentation of symptomatic persistent AF (following the European Society of Cardiology (ESC) guideline 2016) defined as: Persistent AF - AF that lasts longer than 7 days, including episodes that are terminated by cardioversion, either with drugs or by direct current cardioversion, after 7 days or more * Date of first diagnosis of persistent AF within the last 12 months preceding the date of screening * Documented treatment failure or intolerance of at least one Class I or Class III antiarrhythmic drug Key Exclusion Criteria * Known pre-existing hemi-diaphragmatic paralysis * Prior left atrial ablation or surgical procedure (including left atrial appendage closures) * History of right atrial flutter, not ablated prior to enrollment * Any cardiac surgery, myocardial infarction, percutaneous coronary intervention or coronary artery stenting which occurred within the 3 months before the eligibility assessment * Unstable angina pectoris * Primary pulmonary hypertension * Any condition contraindicating chronic anticoagulation * Any cerebral ischemic event (stroke or transient ischemic attack \[TIA\]) which occurred within the 6 months before the consent date * Presence of any cardiac prosthetic valves * Long-standing persistent AF lasting for ≥ 1 year (even when it is decided to adopt a rhythm control strategy) * New York Health Association (NYHA) class III or IV heart failure and/or documented left ventricular ejection fraction (LVEF) \< 40% measured by acceptable cardiac testing (e.g. TTE) * Acute cardiac condition, including endocarditis, pericarditis or pericardial effusion * Presence or likely implant of a permanent pacemaker, biventricular pacemaker or any type of implantable cardiac defibrillator (with or without biventricular pacing function) within 12 months