Introduction

To better understand the mechanisms of gastroesophageal function in patients with gastroesophageal reflux disease (GERD), we assessed healthy individuals using a novel, multi-model study that combined physiology techniques, including high resolution manometry (HRM), 24-hour multichannel-intraluminal impedance-pH (MIIpH), C13 gastric emptying breath testing (GEBT), and body surface gastric mapping (BSGM).

Aims & Methods

Healthy controls were screened and those with a score of 0 on the GERDQ were enrolled. Also, participants completed ROME IV, PAGI-QOL, PAGI-SYM and real time study symptom questionnaires. A 30 minute BSGM baseline was performed after a six hour fast. Then HRM was performed with 10 supine 5 ml swallows to classify esophageal motility followed by a 233 kcal porridge meal labelled with C13 sodium acetate consumed within 10 minutes. Postprandial HRM, GEBT, MIIpH, and BSGM were recorded. After 1 hour HRM was removed and after 4 hours GEBT and BSGM were concluded, but MIIpH testing was continued for the remaining 24 hours. Data were analysed using standard procedures and compared with established reference intervals.

Results

30 healthy volunteers (15 males and 15 females, mean age 31.8 ±9.8 years) completed with none meeting ROME criteria. Mean PAGI-SYM and PAGI-QOL were 3.2 ±5.4 and 4.3 ±7.5, respectively. The mean esophageal acid exposure time (AET) was 2.9% ±4.9 where 3 participants had excessive AET >6%. The mean total number of reflux episodes was 30.5 ±19.9 and the mean number of hypopharyngeal episodes was 1.4 ±12.2. On HRM, 8 participants had ineffective esophageal motility, 1 participant had absent contractility and 1 hypercontractile esophagus. On GEBT, the mean T lag was 47.9 ±18.1 minutes and T ½ was 92.1 ±22.9 minutes. 8 participants had abnormal BSGM but 1 was excluded due to excessive artefact. Of the remaining 7, 5 had low gastric rhythm index, 1 had low frequency and 1 low amplitude. Those with abnormal BSGM were more likely to be male (P = 0.017) and have a hiatus hernia >1.5cm (P = 0.029), but abnormal BSGM in this healthy cohort was not related to any other HRM, MIIpH or GEBT parameters.

Conclusion

These data show it is feasible to perform a combination of techniques to comprehensively assess gastroesophageal function. These normative data can be used to compare with a GERD population to determine pathophysiology of gastroesophageal reflux.

Introduction

Gastric emptying testing (GET) is used to assess gastric motility, however is non-specific and insensitive for neuromuscular disorders. Gastric Alimetry® is a new medical device combining non-invasive gastric electrophysiological mapping and validated symptom profiling.

Aims & Methods

This study aimed to assess patient-specific phenotyping using Gastric Alimetry with comparison to GET.
Patients with chronic gastroduodenal symptoms underwent simultaneous GET and Gastric Alimetry. Tests comprised a 30-minute baseline, ^99mTC-labelled egg meal, and 4-hour postprandial recording. Results were referenced to normative ranges^1,2. Symptoms were profiled in real-time during testing in the validated Gastric Alimetry App³, phenotyped with rule-based criteria, and compared to long-term symptom questionnaires of Rome IV criteria, Patient Assessment of Upper Gastrointestinal Symptom Severity Index (PAGI-SYM), Gastroparesis Cardinal Symptom Index (GCSI), Patient Assessment of Upper Gastrointestinal Disorders Quality of Life (PAGI-QoL), Patient Health Questionnaire-2 (PHQ-2), and State-Trait Anxiety Inventory-6 (STAI-6). Three Gastric Alimetry symptom profiles were phenotyped: i) continuous (symptoms do not correlate with meal or gastric activity); ii) gastric sensorimotor (symptoms increase within 30 minutes of the meal and decay as gastric activity decreases); and iii) Other (symptoms that do not fit the other two symptom profiles).

Results

75 patients with chronic gastroduodenal symptoms were assessed; 77% female, median age 43, median BMI 24.0. Motility abnormality detection rates were: GET 22.7% (14 delayed, 3 rapid); Gastric Alimetry spectral analysis 33.3% (14 dysrhythmic / low amplitude; 5 high amplitude; 6 abnormal frequency); combined yield 42.7%. In patients with normal spectral analysis, Gastric Alimetry symptom phenotypes included: gastric sensorimotor 17%; continuous 30%; other 53%. The sensorimotor phenotype correlated strongly with gastric amplitude (median r=0.61 vs r=0.08 and r=0.06 respectively; p=0.0002). Abnormal Gastric Alimetry phenotypes showed superior correlations with GCSI, PAGI-SYM, and STAI-6 anxiety scores (p<0.05), while Rome IV Criteria and delayed gastric emptying did not correlate (p>0.05). Delayed gastric emptying was not predictive of specific Gastric Alimetry phenotypes.

Conclusion

Gastric Alimetry generated a higher yield for motility abnormalities than GET in patients with chronic gastroduodenal symptoms. Gastric Alimetry also identified patient-specific symptom phenotypes, showing correlations with health psychology variables not observed with Rome IV and delayed gastric emptying. GET and Gastric Alimetry assess different aspects of gastric function, indicating these tests may have complementary roles.

References

1. Varghese C, Schamberg G, Calder S, et al. Normative values for body surface gastric mapping evaluations of gastric motility using gastric alimetry: Spectral analysis. American Journal of Gastroenterology 2022; Publish Ahead of Print. Epub ahead of print 2022. DOI: 10.14309/ajg.0000000000002077.
2. Abell TL, Camilleri M, Donohoe K, et al. Consensus recommendations for Gastric Emptying Scintigraphy: A joint report of the American Neurogastroenterology and Motility Society and the Society of Nuclear Medicine. Journal of Nuclear Medicine Technology; 36: 44–54.
3. Sebaratnam G, Karulkar N, Calder S, et al. Standardized system and app for continuous patient symptom logging in gastroduodenal disorders: Design, implementation, and validation. Neurogastroenterology & Motility 2022; 34. Epub ahead of print 2022. DOI: 10.1111/nmo.14331.

Disclosure

Greg O'Grady, Armen Gharibans and Peng Du hold intellectual property and grants in gastric electrophysiology and are Directors of University of Auckland spin-out companies (Greg O'Grady: Alimetry, Insides Company; Armen Gharibans: Alimetry; Peng Du: FlexiMap); Stefan Calder, Gabriel Schamberg, Stephen Waite, and Christopher N. Andrews are members of Alimetry. The remaining authors have no relevant conflicts of interest to declare.

Introduction

Esophageal mucosal admittance (MA) is a promising diagnostic method for gastroesophageal reflux disease (GERD), however, only some studies were done and mainly in Japan.

Aims & Methods

We conducted a study to describe the esophageal MA in patients with reflux symptoms and determine its diagnostic accuracy. We recruited 92 patients with ambulatory pH-impedance monitoring, upper gastrointestinal endoscopy, and MA measured by the tissue conductance meter. MA was measured during endoscopy at 5cm (distal esophagus) and 15cm above the Z line (middle esophagus), repeated at least five times at each position, and median MA was obtained. Afterwards, two biopsies were taken 5cm above the Z line for histopathological evaluation using the Esohisto criteria. Patients were classified as GERD or non-GERD according to the 2018 Lyon consensus.

Results

The mean age was 43.2 years, and 42 patients were males. The most common symptoms were regurgitation (75.0%), belching (65.2%), and heartburn (46.7%). Twenty-three (32.3%) were diagnosed with GERD using the Lyon consensus, and 24 (26.1%) had esophagitis on histopathology. The median MA at the distal and middle esophagus was moderately correlated. The median MA at both positions was higher in the GERD group but only statistically significant in the middle esophagus. MA was not associated with pH-impedance parameters and esophagitis on histopathology. The diagnostic model developed using the logistic regression did not have good accuracy.

Conclusion

MA was not different between GERD and non-GERD patients. The diagnostic model integrating MA did not have high accuracy in diagnosing GERD.

Clinical Case Summary

Background/History: A 28-year old male presented with symptoms of chest pain, excessive throat noises, bloating and reported inability to belch with specific triggers inclusive of carbonated drinks. Previous treatment included a trial of PPI therapy, cricopharyngeal dilatation and cricopharyngeal Botox therapy - none proved efficacious. High-resolution oesophageal impedance-manometry (OM) and ambulatory 24-hour oesophageal impedance and pH studies (24hr pHZ) were requested to further investigate his symptoms.
Initial findings - standard protocols: Initial OM demonstrated ostensibly normal findings aside from recurrent weak oesophageal motility. 24hr pHZ showed a normal incidence of acidic and non-acidic reflux, however, there was an unusual pattern of recurrent, prolonged periods of gastric belching with apparent re-swallowing of the air bolus [image 1 - pHZ]. In order to reproduce symptoms in clinic and identify whether the air bolus was able to traverse the upper oesophageal sphincter (UOS), this patient was re-referred for OM with addition of a tailored extended protocol.
Extended OM protocol: Addition of a 330mL carbonated drink with positional changes and prolonged monitoring. Symptoms were replicated in clinic with reported chest pain, throat noises and inability to belch. OM showed a repeating pattern of symptomatic gastro-oesophageal gaseous reflux with retrograde movement of air to the distal UOS, followed by increased oesophageal pressure, and failed UOS relaxation which prevented air being expelled as a belch [image 2]. Final diagnosis - RCPD or Abelchia.
Recommended therapeutic management: High dose (100U), multi-site botulinum toxin A (Botox) injection into the cricopharyngeal muscle. The patient is due to undergo repeat Botox therapy.
Points to be discussed: Why did this patient not respond to initial Botox therapy? Failure of the afferent neural pathway to respond to a sub-optimal dose? Recommendation - repeat Botox (higher dose, multi-site).

References

Karagama, Y. 2021. Abelchia: inability to belch/burp—a new disorder? Retrograde cricopharyngeal dysfunction (RCPD). In: European Archives of Oto-Rhino-Laryngology. 278:5087–5091.
Oude Nijhuis, R. A. B., Snelleman, J. A., . Oors, J. M. et al. 2022. The inability to belch syndrome: A study using concurrent high_resolution manometry and impedance monitoring. In: Neurogastroenterology and Motility. y. 34:e14250.

Introduction

Standard-of-care treatments for gastroesophageal reflux disease (GERD) include proton pump inhibitor (PPI)-based medical management and conventional antireflux surgery (i.e., Nissen fundoplication). However, these modalities are associated with a significant burden of unmet needs, such as irresponsiveness and postoperative adverse events (AEs), respectively. This study presents the results of 158 patients managed with RefluxStop in Germany.

Aims & Methods

One-hundred fifty-eight reflux patients were treated with RefluxStop between July 2021 and November 2023. Clinical endpoints included GERD Health-Related Quality of Life (GERD-HRQL), postoperative AEs, and change in PPI use.

Results

Baseline characteristics are shown in Table 1. Median GERD-HRQL score improved by 90.9% from a baseline of 22 (IQR 19-31.5) to 2 (IQR 0-2) at 20±7-month follow-up (p<.001). A 96.3% reduction in PPI use was also observed; baseline PPI use in 96.5% of n=113 decreased to 3.6% of n=110 at follow-up. All cases of preoperative dysphagia (n=18) resolved after surgery. New-onset dysphagia occurred in five patients (3.2%) postoperatively but did not require esophageal dilation. Hiatal hernia recurred in 1.3% (n=2) of patients and was managed with device repositioning. Device penetration and migration occurred in 1.3% (n=2) of patients due to excessively tight suturing of the fundic pouch in which the device was invaginated. One of these patients was later treated by Toupet fundoplication.

Table 1 Baseline characteristics

Conclusion

This report demonstrates the promising clinical effectiveness of RefluxStop as a novel treatment principle in management of GERD. Additional evaluation is necessary to enhance the evidence supporting this new antireflux procedure.

Disclosure

The authors disclose travel grants and speaking honoraria from Implantica (Zug, Switzerland).

Introduction

Solid gastric emptying scintigraphy (GES) is used to assess gastric motility by measuring the transit of a radioactively labelled solid meal, however it can be non-specific and insensitive by itself. Liquid gastric emptying scintigraphy provides an additional modality of motility testing using a similar process with a liquid meal. Gastric Alimetry is a non-invasive test that measures gastric electrophysiological activity through body surface gastric mapping (BSGM) and validated symptom profiling¹.

Aims & Methods

This study aimed to assess the additional diagnostic value of performing liquid GES and Gastric Alimetry in addition to solid GES alone.
Patients with chronic gastroduodenal symptoms underwent simultaneous solid GES and Gastric Alimetry, comprising of a 30-minute baseline recording followed by a 99mTC-labelled egg meal, and 4-hour postprandial recording. Patients would also have a glucose liquid GES study on a different date. Delayed emptying was defined as greater than 10% retention at 4 hours for solid GES and more than 50% retention at 2 hours for liquid GES^2,3. Gastric Alimetry spectral metrics were referenced to normative ranges that included principal gastric frequency (cpm), Gastric Alimetry Rhythm Index (GA-RI) and BMI-adjusted amplitude⁴.

Results

36 patients with chronic gastroduodenal symptoms were prospectively recruited (30 female, median age 38.0 years, median BMI 24.6 kg/m²). 10 (27.8%) patients had delayed solid GES whilst 7 (19.4%) patients had delayed liquid GES. 9 (25.0%) patients had abnormal Gastric Alimetry spectral metrics. Combining solid and liquid GES detected an abnormality in 13 (36.1%) patients which was further enhanced when combined with Gastric Alimetry, detecting an abnormality in 17 (47.2%) of patients. Of those 13 patients with either a delayed solid or liquid GES, 38.5% of them had abnormal Gastric Alimetry spectral metrics (3 High Frequency, 1 Low Rhythm Stability, 1 High Amplitude) while those with a normal solid and liquid GES had abnormal spectral metrics in 17.4%.

Conclusion

Combining solid and liquid GES with Gastric Alimetry detected a higher yield of motility abnormalities than solid GES alone. GES and Gastric Alimetry assess different aspects of gastric function with further studies required to understand their complementary roles as biomarkers in clinical practice to help tailor therapy.

References

1. Sebaratnam G, Karulkar N, Calder S, et al. Standardized system and app for continuous patient symptom logging in gastroduodenal disorders: Design, implementation, and validation. Neurogastroenterology & Motility 2022; 34.
2. Abell TL, Camilleri M, Donohoe K, et al. Consensus recommendations for Gastric Emptying Scintigraphy: A joint report of the American Neurogastroenterology and Motility Society and the Society of Nuclear Medicine. Journal of Nuclear Medicine Technology; 36: 44–54.
3. Phillips WT, McMahan CA, Lasher JC, et al. Anterior, posterior, left anterior oblique, and geometric mean views in gastric emptying studies using a glucose solution. European Journal of Nuclear Medicine; 22: 154–157.
4. Varghese C, Schamberg G, Calder S, et al. Normative values for body surface gastric mapping evaluations of gastric motility using gastric alimetry: Spectral analysis. American Journal of Gastroenterology; 118: 1047–1057.

Disclosure

Greg O'Grady holds intellectual property and grants in gastric electrophysiology and is a Director of the University of Auckland spin-out companies Alimetry and Insides Company. Stefan Calder is a member of Alimetry. The remaining authors have no relevant conflicts of interest to declare.