Abstract: AIM To investigate the effect of electrical stimulation of aortic root ventricular ganglionated plexi (GP) on autonomic nervous system-mediated atrial fibrillation (AF) inducibility. METHODS Effective refractory periods (ERP) of the atria and the pulmonary vein (PV) were measured at baseline, high-level (HL-ES) and low-level (LL-ES) electrical stimulation of aortic root ventricular GP. AF was induced at distal PV by programmed stimulation to measure AF inducibility at baseline, HL-ES or LL-ES. RESULTS HL-ES of aortic root GP significantly shortened ERP of the atria and ERP of the PVs and increased the AF-inducing rate arising from PVs. However, LL-ES of this GP prevented the shortening of ERP and decreased AF inducing rate. CONCLUSION LL-ES of aortic root ventricular GP decreases AF inducibility arising from PVs mediated by the autonomic nervous system.