Abstract 2545: Elimination of Pulmonary Vein Firing and Fractionated Atrial Potentials by Ablation of Autonomic Ganglionated Plexi
Recent animal studies show that ganglionated plexi (GP) stimulation produces pulmonary vein firing (PV) and fractionated atrial potentials (FAP) by shortening refractoriness of PV/atrial myocardium and enhancing Ca loading (triggered firing). We hypothesized that GP ablation reduce PV firing and FAP in atrial fibrillation (AF) patients.
Methods: In 40 AF pts (paroxysmal 30) undergoing AF ablation, an electroanatomical map of the LA and PV was obtained during AF. Electrograms were recorded for 2.5 sec at each site. Using CFAE software on CARTO-RMT (Biosense Webster), FAP segments were defined as potentials with low amplitude (0.03– 0.2 mV) and very short inter-potential interval (15– 80 ms). FAP areas were defined as greatest number of FAP segments (≥40 FAP segments/2.5 sec). GP were localized by high frequency stimulation (HFS, 20 Hz), identified by a positive vagal response (≥50% increase in R-R interval).
Results : 4 distinct FAP areas during AF were present in LA (Superior Left, Left Atrial Appendage Ridge, Inferior-Posterior, and Anterior Right FAP Areas). The 5 major GP (Superior Left, Marshall Tract, Inferior Left, Inferior Right, and Anterior Right GP) were located centrally in FAP areas (Fig⇓). RF (18 –30 RFs) was delivered at the 5 major GP sites and eliminated vagal response to HFS. GP ablation alone (before PV isolation) significantly decreased PV firing (26/40 pts vs. 6/40 pts, p<0.01) and the inducibility of sustained AF (33/40 pts vs. 20/40 pts, p<0.01). In 20 pts with sustained AF after GP ablation, FAP areas during AF markedly decreased (median 30.9 cm2 vs. 4.1 cm2, p<0.01).
Conclusions: GP ablation reduces PV firing and AF inducibility and eliminates majority of FAP areas.