Background: Circumferential pulmonary vein isolation (CPVI) often cause unavoidable vagal reflexes during procedure due to the coincidental modification of ganglionated plexus which are located on pulmonary vein (PV) antrum. The right anterior ganglionated plexi (RAGP) which located at superoanterior area of right superior PV antrum is an essential station to regulate the cardiac autonomic nerve activities and is easily coincidentally ablated during CPVI. The aim of this study is to assess the effect of RAGP ablation on vagal response (VR) during CPVI.
Methods: A total of 80 patients with paroxysmal atrial fibrillation who underwent the first time CPVI were prospectively enrolled and randomly assigned to 2 groups: group A (n=40), CPVI started with right PVs at RAGP site; group B (n=40): CPVI started with left PVs first, and the last ablation site is RAGP. Electrophysiological parameters include basal cycle length, A-H interval, H-V interval, sinus node recovery time, and atrioventricular node Wenckebach point were recorded before and after CPVI procedure.
Results: During CPVI, the positive VR were only observed on 1 patient in group A and 25 patients in group B (P<0.001). A total of 21 patients with positive VR in group B needed for temporary ventricular pacing during procedure, while the only patient with positive VR in group A did not need for temporary ventricular pacing (P<0.001). Compared with baseline, basal cycle length, sinus node recovery time, and atrioventricular node Wenckebach point were decreased significantly after CPVI procedure in both groups (all P<0.05) and without differences between 2 groups.
Conclusions: Circumferential PV isolation initiated from RAGP could effectively inhibit VR occurrence and significantly increase heart rate during procedure.
Keywords: atrial fibrillation; atrioventricular block; atrioventricular node; heart rate; pulmonary vein.