Characteristics of reflux and gastric electrical activity in Gastroesophageal Reflux Disease with Ineffective Esophageal Motility

OBJECTIVES

The impact of ineffective esophageal motility (IEM) on gastroesophageal reflux disease (GERD) remains unknown and abnormal esophageal motility often coexists with abnormal gastric motility. So this research aimed to explore the role of IEM in GERD and its relationship with gastric electrical activity.

METHODS

Patients with GERD-questionnaire ≥8 in our hospital from January 2020 to June 2022 were included. All patients accepted 24 h esophageal pH-impedance monitoring, high-resolution manometry and electrogastrogram examination and were divided into normal esophageal motility (NEM) group and IEM group. Reflux characteristics, gastric electric activity were compared between the two groups and the correlation between gastric electric activity and reflux was analyzed.

RESULTS

Acid exposure time, total reflux episodes and DeMeester score in IEM group were statistically higher than NEM group. Distal mean nocturnal baseline impedance were significantly lower in IEM group. Compared with NEM group, power ratio (PR) of fundus, antrum and pylorus, pre-meal and post-meal normal waves ratio of antrum were significantly lower in IEM group. The total reflux episodes were negatively correlated with PR of fundus and pylorus, and the DeMeester score was negatively correlated with PR of body and pylorus.

CONCLUSIONS

IEM may lead to increased reflux, resulting in esophageal mucosal damage. There may be consistency between abnormal esophageal motility and gastric motility. This article is protected by copyright. All rights reserved.

A central amygdala input to the dorsal vagal complex controls gastric motility in mice under restraint stress

Background/aims: Psychological and physiological stress can cause gastrointestinal motility disorders. Acupuncture has a benign regulatory effect on gastrointestinal motility. However, the mechanisms underlying these processes remain unclear. Methods: Herein, we established a gastric motility disorder (GMD) model in the context of restraint stress (RS) and irregular feeding. The activity of emotional center-central amygdala (CeA) GABAergic neurons and gastrointestinal center-dorsal vagal complex (DVC) neurons were recorded by electrophysiology. Virus tracing and patch clamp analysis of the anatomical and functional connection between the CeA^GABA → dorsal vagal complex pathways were performed. Optogenetics inhibiting or activating CeA^GABA neurons or the CeA^GABA → dorsal vagal complex pathway were used to detect changes in gastric function. Results: We found that restraint stress induced delayed gastric emptying and decreased gastric motility and food intake. Simultaneously, restraint stress activated CeA GABAergic neurons, inhibiting dorsal vagal complex neurons, with electroacupuncture (EA) reversing this phenomenon. In addition, we identified an inhibitory pathway in which CeA GABAergic neurons project into the dorsal vagal complex. Furthermore, the use of optogenetic approaches inhibited CeA^GABA neurons and the CeA^GABA → dorsal vagal complex pathway in gastric motility disorder mice, which enhanced gastric movement and gastric emptying, whereas activation of the CeA^GABA and CeA^GABA → dorsal vagal complex pathway mimicked the symptoms of weakened gastric movement and delayed gastric emptying in naïve mice. Conclusion: Our findings indicate that the CeA^GABA → dorsal vagal complex pathway may be involved in regulating gastric dysmotility under restraint stress conditions, and partially reveals the mechanism of electroacupuncture.

Late-onset rapid gastric emptying: Identification of a new abnormal finding in patients with otherwise normal results on gastric emptying scintigraphy

BACKGROUND

The 4-h gastric emptying (GE) scintigraphy protocol is the gold standard for assessing GE. Rapid gastric emptying (RGE) is >30% emptied by 30 min and >65% emptied at1 h. We observed that some GE studies demonstrated rapid emptying at a later time although interpreted as normal (NGE) at 4 h. We aimed to establish thresholds to characterize this subset of late-onset rapid gastric emptying (LRGE).

METHODS

We retrospectively analyzed 4-h GE studies of 425 patients with upper GI symptoms who fulfilled the criteria for NGE. We recruited 24 normal subjects to establish GE cutoff values (mean +/- 2SD) at 1-2, 2-3, and 3-4 h. These thresholds were applied to the 425 patients with NGE. During every GE study, patients graded their postprandial symptoms on a scale from 0 to 4.

KEY RESULTS

The mean upper threshold decrement limits were calculated from the normal volunteers as 67.6% at 1-2 h, 48.7% at 2-3 h, and 27.9% at 3-4 h. After applying these values to the NGE patients, 19 (4.5%) were classified as having LRGE; 6 patients (1.4%) for the 2- to 3-h; and 13 (3.1%) for the 3- to 4-h period. Patients with LRGE had abdominal pain, bloating, nausea, or diarrhea beginning more than 1-h postprandial.

CONCLUSION

5% of patients classified as "normal" at 4 h had an abnormal GE pattern based on the proposed criteria for LRGE. This highlights the importance of applying these hourly decrement thresholds to identify LRGE as a new diagnostic entity explaining postprandial symptoms.