Atrial Remodeling After PFA Substrate Modification for Persistent AF (PeAF)

Atrial fibrillation (AF) is associated with both electrical and structural remodeling of the left atrium. While successful catheter ablation has been shown to reverse some aspects of atrial remodeling, the impact of pulsed-field ablation (PFA) - a non-thermal ablation technology that selectively targets cardiomyocytes while sparing surrounding structures - on atrial remodeling in patients with persistent AF undergoing extensive substrate modification remains unclear. This is a prospective, single-center, single-arm observational study conducted at Taipei Veterans General Hospital. The study will enroll 30 patients with persistent atrial fibrillation who undergo pulmonary vein isolation (PVI) and extensive substrate modification using the FARAWAVE / FARADRIVE Catheter and FARASTAR System. The primary objective is to evaluate left atrial structural remodeling following PFA, including changes in LA size, atrial strain, extent of atrial fibrosis, and atrial hemodynamic function. The secondary objective is to assess AF-free survival between 3 and 12 months after the procedure, and its relationship to atrial remodeling. All participants will be followed for 12 months, with an interim analysis conducted once all subjects complete their 6-month follow-up.

Inclusion Criteria: * Diagnosis of persistent atrial fibrillation * Left atrial anteroposterior (AP) diameter greater than 4 cm and less than 6 cm * Anti-arrhythmic medications (except amiodarone) discontinued for at least 5 half-lives before the procedure * No use of beta-blockers or diuretics before or after the ablation procedure * Willing and able to provide written informed consent Exclusion Criteria: * Paroxysmal atrial fibrillation * Previous left atrial surgery or catheter ablation procedure, including left atrial appendage closure * Atrial fibrillation due to reversible causes, such as thyroid disorders, acute alcohol intoxication, or other major surgeries within the 90 days preceding the procedure * Myocardial infarction, acute coronary syndrome, percutaneous coronary intervention, or coronary artery bypass grafting within 90 days of the procedure * Known presence of cardiac thrombus * Stroke or transient ischemic attack within the last 90 days * Any other anatomical or comorbid condition that, in the investigator's opinion, could limit the patient's ability to participate in the clinical trial, comply with follow-up requirements, or impact the scientific validity of the clinical trial results