Preliminary study on high resolution mapping in human gastric electrical activities / 中华消化杂志

ABSTRACT

Objective To investigate the spatio-temporal characteristics of normal gastric electrical activity.Methods From January 1st to February 29th,2016,fasting gastric electric slow wave signal was collected by high resolution mapping (HRM) under anesthesia before operation in patients without gastric lesions but needed laparoscopic surgery.Parameters of slow wave signal activity was calculated,gastric activity map and velocities was drawn and then spatio-temporal characteristics of gastric electrical activity of different part of the stomach were obtained.Independent sample t test was performed for comparison of two groups and one-way analysis of variance was used for multiple group comparisons.Results The normal gastric pacing zone located in the upper middle part of gastric body near greater curvature.Electrical activity of gastric body spread to gastric antrum along the long axis of the stomach.No slow signal was recorded in the gastric fundus and the gastric cardia.The frequencies of slow waves of different parts of gastric was same and the mean value was 2.61 ±0.11 cycle per minute.Compared with that of gastric body,the slow wave amplitude of gastric pacing zone was higher ((4.19±0.73) mV vs (1.67± 0.89) mV) and the speed was faster (7.24± 1.37) mm/s vs (4.94± 0.20) mm/s);the differences were statistically significant (t=18.89 and 4.95,both P＜0.01).The slow wave amplitude of gastric antrum was higher than that of gastric body ((3.21±0.49) mV vs (1.67±0.89) mV) and the speed was also faster ((6.44±0.82) mm/s vs (4.94±0.20) mm/s);the differences were statistically significant (t=4.85 and 4.95,both P＜0.05).The slow wave amplitude of gastric antrum was lower than that of pacemaker area ((3.21±0.49) mV vs (4.19±0.73) mV),and the difference was statistically significant (t =-3.67,P＜0.05);however,there was no significant difference in wave velocity ((6.44±0.82) mm/s vs (7.24±1.37) mm/s,P＞0.05).Conclusions The normal human gastric pacemaker is located in mid and upper corpus near the greater curvature,which produces slow wave and control whole gastric electrical activity.The amplitude and velocity of slow waves are in gradient changes in different gastric regions.HRM is a mature and reliable research method to study the spatio-temporal characteristics of gastric electrical activity,which provides the possibility for the study of abnormal gastric electrical activity.