Gastroesophageal reflux disease and atrial fibrillation: Insight from autonomic cardiogastric neural interaction

Background: The relationship between gastroesophageal reflux disease (GERD) and atrial fibrillation (AF) has been previously reported. However, the detailed mechanism remains unknown. In this study, we investigated the effects of acid reflux on the intrinsic cardiac autonomic nervous system, atrial/ventricular electrophysiology, and AF inducibility. Methods: Eighteen rabbits were randomized into three groups: acid reflux (group 1, n = 6), control (group 2, n = 6), and acid reflux with periesophageal vagal blockade (group 3, n = 6). Atrial and ventricular effective refractory periods (ERPs) and AF inducibility were checked at baseline and then hourly until 5 hours after the experiment. Results: Three hours after the experiment, atrial ERP prolongation was noted in groups 2 and 3 (P <.05), whereas shortening of the atrial ERPs was observed in group 1, compared with the baseline. However, no changes were observed in ventricular ERPs in the three groups. The AF inducibility was higher in group 1 than in groups 2 and 3. Pathological examination showed clear esophageal mucosal breaks in groups 1 and 3. Conclusions: In this study, we found that the antimuscarinic blockade prevents GERD induced changes to atrial electrophysiology and susceptibility to AF—making it highly likely that autonomic activity is important in mediating this effect.