Auto Reference Vector: A Novel Method for Mapping Atrial Fibrillation

Abstract

Background: A standardized approach for constructing electroanatomical activation maps of atrial fibrillation (AF) has not yet been established. Objective: This study introduces a novel mapping technique, the Auto Reference Vector (ARV), and evaluates its ability to characterize AF activation patterns and guide ablation of focal sources, with a particular emphasis on achieving AF non-inducibility. Methods: Forty-seven patients with AF (mean age, 71.1 ± 11.6 yr; 30 males; 30 with persistent AF; 34 undergoing repeat procedures) underwent catheter ablation. During AF mapping, the B2–C2 electrodes of a high-density grid catheter served as an internal reference to compute omnipolar vectors. Activation patterns were classified, and focal sources characterized by predominant centrifugal vectors were targeted for ablation. In 12 patients, repeated mapping was performed to assess the reproducibility of ARV data. Results: Nearly all redo cases (33/34) demonstrated organized activation whereas most de novo cases (9/13) showed disorganized patterns. Prior ablation and longer AF cycle length were significantly associated with organized activation (p < 0.001 and p = 0.02, respectively). In total, 113 focal sources were identified in 41 patients, the majority located in the left atrium (91/113; 80%). Ablation of these sources led to immediate AF termination in 12 of 38 patients (32%) and achieved final AF non-inducibility in 33 of 38 patients (87%). Conclusions: ARV mapping enables reliable identification of organized AF activation patterns, particularly in patients with prior ablation. Targeted ablation of ARV-identified focal sources effectively suppresses AF. Further studies are warranted to validate the long-term efficacy of this strategy.