Impact of ganglionated plexi ablation on high-frequency stimulation-induced changes in atrial fibrillation cycle length in the pulmonary vein

BackgroundWe assessed high-frequency stimulation (HFS)-induced changes in the atrial fibrillation (AF) cycle length (AFCL) in the pulmonary vein (PV) after ganglionated plexi (GP) ablation.MethodsTwenty-two patients undergoing catheter ablation for AF were retrospectively enrolled. Sites showing a vagal response (VR) to HFS were defined as GP-positive sites. AFCL was determined in the adjacent PV, distant PV, coronary sinus, and right atrium. Twenty cycles were counted before and after each HFS. After radiofrequency application to the GP site, HFS was repeated.ResultsAt GP-positive sites (n=57), significant shortening of the AFCL was detected in the adjacent PV (17% shortening, 165±38 to 137±27 ms, p<0.001) and distant PV (4.8% shortening, p<0.001), but not in the coronary sinus (0.8% shortening, p=0.27) or right atrium (1.8% shortening, p=0.06). However, no significant shortening was observed at GP-negative sites (n=25). At 41 of the 57 sites where VR disappeared after a single radiofrequency application, no significant shortening was observed in the adjacent PV (2.1% shortening, p=0.25). At 16 of the 57 sites where VR was still present, significant shortening was observed in the adjacent PV (16% shortening, p<0.001).ConclusionsHFS of the GP has a strong influence on AFCL in the PV.