Background
Dipole density (DD) guided catheter ablation (CA) for persistent atrial fibrillation (persAF) using the AcQMap® system has been proven to be feasible and effective. The latter is a non-contact high-resolution system using a single array-shaped catheter providing 48 ultrasound probes and electrodes for 3D anatomy reconstruction and continuous DD mapping, displaying AF wave fronts, and enabling DD guided CA. However, real long-term outcome data for DD guided CA is sparse.

Objective
We sought to provide the first long-term outcome data for persAF patients after DD guided CA in comparison to conventional CA for persAF.

Methods
Long-term freedom from AF and atrial tachycardia (AT) after DD guided CA was obtained by repeated holter-ecg and out clinic patient visits. For comparison a pair-matched analysis with patients undergoing conventional PVI for persAF using a contact force catheter and 3D-mapping system was performed.

Results
A total of 30 patients (15 DD guided CA and 15 conventional PVI) undergoing CA for persAF were analyzed. After a follow-up of 46±19 months 33% (n=5) of patients undergoing DD guided CA were free from any atrial arrhythmia as compared to 53% (n=8) of patients after conventional CA (HR 1.13; p=0.818). After DD guided CA freedom from AF was 40% (n=6) vs. 73% (n=11) (HR 1.58; p=0.483). Occurrence of atrial tachycardia (AT) was equal for both groups (20%; n=3) (HR 0.98; p=0.973).
For DD guided CA the procedure duration was significantly longer (231±44 vs. 136±43 minutes; p<0.0001). Furthermore, the fluoroscopy duration (36.49±14.38 vs. 13.78±7.27 minutes; p<0.0001) and dosage (10070.33±5053.35 vs. 2753.27±1754.04 mGy*cm2; p<0.0001) was significantly higher as compared to conventional PVI.

Conclusion
A four-year follow-up in patients after successful DD guided CA for persAF revealed no benefit for AF and AT free survival in comparison to conventional PVI in persAF. Of note, procedure and fluoroscopy duration as well as dosage for DD guided CA was significantly higher indicating a higher level of complexity in DD guided ablation.