Targeting Nonpulmonary Vein Sources in Persistent Atrial Fibrillation Identified by Noncontact Charge Density...

Area of Science:

• Cardiology
• Electrophysiology
• Medical Imaging

Background:

• Persistent atrial fibrillation (AF) management requires targeting non-pulmonary vein sources.
• Novel catheter ablation strategies aim to improve clinical outcomes in AF patients.
• Noncontact mapping systems offer potential for precise arrhythmia targeting.

Purpose of the Study:

• To evaluate a novel ultrasound imaging and charge density mapping system for guiding catheter ablation in persistent AF.
• To assess the safety and effectiveness of targeting non-pulmonary vein ablation sites.
• To determine the rate of freedom from AF after a single procedure and after repeat procedures.

Main Methods:

• Prospective, nonrandomized trial (UNCOVER AF) involving 127 patients with persistent AF undergoing de novo catheter ablation.
• Utilized an ultrasound-based system to reconstruct atrial anatomy and map ionic charge density.
• Ablation targets were identified based on charge density mapping, followed by iterative remapping and ablation.
• AF recurrence was monitored using 24-hour ECGs at 3, 6, 9, and 12 months.

Main Results:

• Acute procedural efficacy was high, with 98% of patients undergoing successful mapping and ablation.
• At 12 months, 72.5% of patients achieved freedom from AF after a single procedure.
• Freedom from AF increased to 93.2% after one or two procedures.
• The primary safety outcome was met, with a 98% freedom from major adverse events and no device-related events.

Conclusions:

• The novel ultrasound imaging and charge density mapping system provides a safe and effective method for guiding catheter ablation in persistent AF.
• The system enables precise identification and ablation of non-pulmonary vein targets, improving procedural outcomes.
• High rates of freedom from AF were achieved, particularly after a second procedure, highlighting the system's potential to enhance AF management.