Characteristics Of Continuous Complex Fractionated Atrial Electrograms In Pulmonary Veinsostia And Left Atrium During Atrial Fibrillation

CFAEs demonstrating the complex atrial electrical activity recorded during atrial fibrillation(AF) have been proposed to represent the substrate maintaining AF. The efficacy of CFAEstargeted ablation have been convinced by lots of reports, however, the outcome following CFAEablation remains controversial. The study was to evaluate the electrophysiologic characteristics ofCFAEs in the PVO and LA using a three-dimensional electroanatomic mapping system during AF,which would facilitate to the sites of CFAEs ablated.Objective To investigate the electrophysiologic characteristics of continuous CFAEs in thePVO and LA during AF. Methods24patients with drug refractory PAF group (n=12) and PeAFgroup (n=12) were enrolled. The PVO was divided into area I and II, the distance of which was5-10mm and10-20mm from the PV orifices. High-density mapping the PVO and LA was performedusing a three-dimensional electroanatomic mapping system (EnSite NavX) during spontaneous orinduced AF. The electrophysiologic characteristics of the continuous CFAEs (CFE-mean≤70ms)was compared between two groups. Results①The average LA diameter in PeAF group waslarger than the PAF group (P<0.05). In the PAF group, the lest and most prevalent continuousCFAEs seperately were in the LA roof and posterior wall, while in the PeAF group, those were inthe LA posterior or anterior walls, and appendage, seperately. The prevalence of the continuousCFAEs in the PVO which was apparently more prevalent than the LA (P<0.05) in the PAF group,and was similar in the PeAF group.②In the PeAF group, the continuous CFAEs at the LA wasmore prevalent in the PVO (P<0.05), but was equally prevalent in the PVO between two group(P=0.58). More continuous CFAEs recorded at the left inferior PVO in the PAF group (P=0.02),while no significant difference of the continuous CFAEs distribution was found in the other PVObetween two groups. Except for the LA roof, where more continuous CFAEs distribution in thePAF group than the PeAF group were observed (P=0.02), those at the LA posterior wall,appendage, and mitral annulus in the PeAF group were more prevalent than the PAF group, andwere fairly distributed in the other LA regions.③The prevalece of the continuous CFAEs at areaⅠin each PVO in PAF group was more than area Ⅱ(P<0.05). More continuous CFAEs in left inferior PVO and less continuous CFAEs in right superior PVO at areaⅠwere recorded in PeAFgroup, and without significance differencs in other PVOs.④In the PAF group, CFE-mean valuewas significantly lower in the PVO compared with the LA (P<0.05), which was withoutsignificant difference between two regions in the PeAF group and in the PVO between two groups.Lower CFE-mean value, more points of continuous CFAEs (P=0.001) and AFCL (P=0.006) wererecorded in the PeAF group compared with the PAF group. Conclusions The higher prevalenceand duration of the continuous CFAEs in the LA and the longer AFCL in PeAF than PAFdemonstrate that the anatomically and electroanatomically remodeled LA plays an important rolein maintaining AF. Most continuous CFAEs in PVO are concentrated in the5-10mm area.