Minimal Configuration of Body Surface Potential Mapping for Discrimination of Left and Right Atrial Drivers of Atrial Fibrillation

Aim: Ablation of drivers that maintain Atrial Fibrillation (AF) has been demonstrated as an effective therapy. Left and right atrial (LA, RA) drivers can be non-invasively located with Body Surface Potential Mapping (BSPM) systems, but the future widespread clinical usage of such systems is uncertain due in part to their complex methodology of handling an extremely high number of electrodes on the body surface. The objective of this study is to investigate the effect of reduced number of surface leads on detection and localization of atrial drivers of AF on the torso surface with the aim of establishing a reduced-leads BSPM system.

Methods and Results: Sixty-six BSPM signals were registered simultaneously with intracardiac EGM recordings in 14 AF patients. BSPM signals were selected to form 9 different sets of uniformly distributed leads ranging 8 to 66 electrodes. Body surface Dominant Frequencies (DF) and rotor activity were characterized using the 9 different leads mapping arrangements, and the non-invasive measures were compared with the intrcaradiac EGM recordings. The non-invasive DFs measures had a high correspondence with the intracardiac recordings: for all surface lead sets with 12 or more electrodes they presented a deviation of less than 0.5 Hz for the highest DF and a correlation coefficient higher than 0.8. The surface rotor distribution presented also a high correlation with the 66 leads BSPM system for sets with 32 or more electrodes. The surface reentrant activity at the torso areas corresponding to the LA and RA electrical activity presented significant specificity to the fastest intracardiac LA or RA for surface sets with 24 or more leads.

Conclusions: Reduced-leads BSPM systems of 32 electrodes allow differentiating between LA or RA atrial drivers with similar results as 66 electrodes systems. This finding paves the way for the incorporation into clinical practice of BSPM systems that are simpler than those currently used.