Ameliorating Effects and Autonomic Mechanisms of Transcutaneous Electrical Acustimulation in Patients With Gastroesophageal Reflux Disease

Background/Aim Gastric dysmotility is one of pathophysiologies of gastroesophageal reflux disease (GERD). The aim of this study was to investigate the effects of transcutaneous electrical acustimulation (TEA) on gastric accommodation and gastric slow waves, and evaluate possible mechanisms in patients with GERD. Methods Thirty patients were studied in two randomized sessions of sham-TEA and TEA with the measurements of esophageal high-resolution manometry (HRM), gastric accommodation assessed by a nutrient-drinking test, electrogastrogram (EGG), electrocardiogram (ECG), and postprandial dyspeptic symptoms. Results Compared with sham-TEA, TEA improved nutrient drinking-induced fullness (42.0 +/- 3.3 vs. 31.0 +/- 3.5, P = 0.003) at 10 min after the drink, and belching right after the drink (22.0 +/- 4.6 vs. 11.7 +/- 3.1, P = 0.012) and at 10 min (16.0 +/- 3.8 vs. 3.0 +/- 1.5, P = 0.002) after the drink. TEA also improved gastric accommodation (954 +/- 37 mL vs. 857 +/- 47 mL, P = 0.001) and normalized maximal drink-induced impairment in gastric slow waves. Concurrently, TEA enhanced vagal activity assessed from spectral analysis of heart rate variability in the postprandial state (0.42 +/- 0.03 vs. 0.49 +/- 0.04, P = 0.039). The vagal activity was positively correlated with the percentage of normal slow waves (r = 0.528; P = 0.003) and negatively correlated with the regurgitation score (r = -0.408, P = 0.025). Conclusions Acute TEA increases gastric accommodation, improves gastric slow waves, and reduces postprandial fullness and belching, possibly mediated via the vagal mechanisms.