Spatial relationship of localized sources of persistent atrial fibrillation identified by a unipolar-based automated algorithm to complex fractionated atrial electrocardiograms and atrial low voltage areas

IntroductionSpatial characteristics of localized sources of persistent atrial fibrillation (AF) identified by unipolar-based panoramic mapping software (CARTOFINDER) remain unclear. We evaluated spatial characteristics of bi-atrial AF localized sources in relation to complex fractionated atrial electrocardiograms (CFAEs) and atrial low voltage area (LVAs) (<= 0.35 mV during AF). Methods and ResultsTwenty consecutive patients with persistent AF underwent bi-atrial voltage, CFAE, and CARTOFINDER mapping before the beginning of ablation (18 [90%] patients, initial procedure; 2 [10%] patients, repeat procedure). CFAEs were recorded using the interval confidence level (ICL) mode and defined as sites with a confidence level of >= 80% of maximal ICL number. We elucidated the following: (1) differences in the rate of AF localized sources and CFAEs inside or outside the atrial LVAs; (2) distribution of AF localized sources and CFAEs; and (3) distance between the closest points of AF localized sources and CFAEs.A total of 270 AF localized sources and 486 CFAEs were identified in 20 patients. AF localized sources were confirmed more often outside atrial LVAs than CFAEs (71% vs. 46% outside LVA, p < .001). AF localized sources and CFAEs were diffusely distributed without any tendency in bi-atria. Mean distance between closest AF localized sources and CFAEs was 22 +/- 8 mm. ConclusionAF localized sources identified by CARTOFINDER are different therapeutic targets as compared to CFAEs and could be confirmed both inside and outside atrial LVAs.