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Huang IH, Calder S, Gharibans AA, Schamberg G, Varghese C, Andrews CN, Tack J, O'Grady G. Meal effects on gastric bioelectrical activity utilizing body surface gastric mapping in healthy subjects. Neurogastroenterol Motil 2024; 36:e14823. [PMID: 38764250 DOI: 10.1111/nmo.14823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 05/01/2024] [Accepted: 05/09/2024] [Indexed: 05/21/2024]
Abstract
BACKGROUND Gastric sensorimotor disorders are prevalent. While gastric emptying measurements are commonly used, they may not fully capture the underlying pathophysiology. Body surface gastric mapping (BSGM) recently emerged to assess gastric sensorimotor dysfunction. This study assessed varying meal size on BSGM responses to inform test use in a wider variety of contexts. METHODS Data from multiple healthy cohorts receiving BSGM were pooled, using four different test meals. A standard BSGM protocol was employed: 30-min fasting, 4-h post-prandial, using Gastric Alimetry® (Alimetry, New Zealand). Meals comprised: (i) nutrient drink + oatmeal bar (482 kcal; 'standard meal'); (ii) oatmeal bar alone; egg and toast meal, and pancake (all ~250 kcal). Gastric Alimetry metrics included BMI-adjusted Amplitude, Principal Gastric Frequency, Gastric Alimetry Rhythm Index (GA-RI) and Fed:Fasted Amplitude Ratio (ff-AR). KEY RESULTS 238 participants (59.2% female) were included. All meals significantly increased amplitude and frequency during the first postprandial hour (p < 0.05). There were no differences in postprandial frequency across meals (p > 0.05). The amplitude and GA-RI of the standard meal (n = 110) were significantly higher than the energy bar alone (n = 45) and egg meal (n = 65) (all p < 0.05). All BSGM metrics were comparable across the three smaller meals (p > 0.05). A higher symptom burden was found in the oatmeal bar group versus the standard meal and pancake meal (p = 0.01, 0.003, respectively). CONCLUSIONS & INFERENCES The consumption of lower calorie meals elicited different postprandial responses, when compared to the standard Gastric Alimetry meal. These data will guide interpretations of BSGM when applied with lower calorie meals.
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Affiliation(s)
- I-Hsuan Huang
- Translational Research Center for Gastrointestinal Disorders, University of Leuven, Leuven, Belgium
- Department of Gastroenterology and Hepatology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Stefan Calder
- Alimetry Ltd, Auckland, New Zealand
- Department of Surgery, University of Auckland, Auckland, New Zealand
| | - Armen A Gharibans
- Alimetry Ltd, Auckland, New Zealand
- Department of Surgery, University of Auckland, Auckland, New Zealand
| | - Gabriel Schamberg
- Alimetry Ltd, Auckland, New Zealand
- Department of Surgery, University of Auckland, Auckland, New Zealand
| | - Chris Varghese
- Department of Surgery, University of Auckland, Auckland, New Zealand
| | - Christopher N Andrews
- Alimetry Ltd, Auckland, New Zealand
- Division of Gastroenterology, Cumming School of Medicine, University of Calgary, Calgary, Canada
| | - Jan Tack
- Translational Research Center for Gastrointestinal Disorders, University of Leuven, Leuven, Belgium
| | - Greg O'Grady
- Alimetry Ltd, Auckland, New Zealand
- Department of Surgery, University of Auckland, Auckland, New Zealand
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2
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Xu W, Williams L, Sebaratnam G, Varghese C, Cedarwall C, Daker C, Keane C. Gastric Alimetry® Testing and Healthcare Economic Analysis in Nausea and Vomiting Syndromes. Dig Dis Sci 2024; 69:2304-2314. [PMID: 38689198 PMCID: PMC11258171 DOI: 10.1007/s10620-024-08455-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Accepted: 04/17/2024] [Indexed: 05/02/2024]
Abstract
BACKGROUND Chronic nausea and vomiting syndromes (CNVS), gastroparesis and functional dyspepsia (FD) are complex disorders. Body Surface Gastric Mapping (BSGM), a new test of gastric function, using Gastric Alimetry® (Alimetry, New Zealand) may be useful for de-escalating healthcare utilisation. This study aimed to define healthcare costs and estimate health economic impacts of implementing this test in patients with chronic gastroduodenal symptoms. METHODS Consecutive patients at a tertiary referral centre evaluated with Gastric Alimetry were included. Frequency and cost data relating to medical investigations, hospital and outpatient presentations were evaluated. Costs of healthcare utilisation were calculated, and the potential cost savings of implementing Gastric Alimetry within a diagnostic decision-tree model were estimated. RESULTS Overall, 31 consecutive patients (mean age 36.1 years; 83.9% female; predominant symptoms: nausea [83.9%], pain [61.3%], vomiting [67.7%] and bloating [35.5%]) completed Gastric Alimetry testing. Repeat gastroscopy and abdominal CT rates were 29% (8/28) and 85% (11/13), respectively. Gastric Alimetry testing identified spectral abnormalities in 45.2% of patients, and symptom profiling classified a further 29.1% of patients. Median annualised cost difference after test introduction was NZ$-12,032. Estimated reductions in investigation-related costs when incorporating Gastric Alimetry into the diagnostic workflow model were approximately NZ$1,300 per patient. CONCLUSIONS Healthcare utilisation and confirmatory testing rates remain high in nausea and vomiting syndromes. This study presents real-world data, together with a decision-tree analysis, showing Gastric Alimetry can streamline clinical care pathways, resulting in reduced healthcare utilisation and cost.
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Affiliation(s)
- William Xu
- The University of Auckland, Auckland, New Zealand
- Te Tai Tokerau District, Te Whatu Ora, Whangarei, New Zealand
- Department of Surgery, University of Auckland, Auckland, New Zealand
| | | | | | - Chris Varghese
- The University of Auckland, Auckland, New Zealand
- Counties Manukau District, Te Whatu Ora, Whangarei, New Zealand
- Department of Surgery, University of Auckland, Auckland, New Zealand
| | - Chris Cedarwall
- Capital and Coast District, Te Whatu Ora, Whangarei, New Zealand
| | | | - Celia Keane
- Te Tai Tokerau District, Te Whatu Ora, Whangarei, New Zealand.
- Department of Surgery, University of Auckland, Auckland, New Zealand.
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Sadder LS, Brown LS, Roblyer L, Sanghavi R, Ortigoza EB. Antibiotic duration and gastric dysmotility in preterm neonates. J Pediatr Gastroenterol Nutr 2024. [PMID: 38708837 DOI: 10.1002/jpn3.12235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 03/14/2024] [Accepted: 04/15/2024] [Indexed: 05/07/2024]
Abstract
OBJECTIVES Prolonged antibiotic use after birth is associated with neonatal feeding intolerance and functional gastrointestinal disorders (FGIDs). A gastric dysrhythmia (tachygastria) with frequencies >4-9 cycles per minute, measured by electrogastrography (EGG), is associated with FGIDs. The relationship between prolonged antibiotic use and % time spent in tachygastria is unknown in preterm infants. We aimed to compare weekly changes in % tachygastria between preterm infants receiving long (>48 h) versus short (≤48 h) courses of antibiotics for early onset sepsis evaluation (initiated at <3 days of life). METHODS This was a longitudinal, prospective cohort study of 88 preterm infants (<34 weeks' gestation) with weekly EGG recordings from the first week of life until 40 weeks' post-menstrual age, discharge, or death. We calculated % of EGG recording time in tachygastria and determined the mean across weekly sessions. A mixed effects model assessed variance in % tachygastria between the short- and long-antibiotic exposure groups across all weeks. RESULTS Baseline characteristics were similar between the two groups. There was no difference in % tachygastria between short and long antibiotic exposure groups across nine postnatal weeks (p = 0.08). CONCLUSIONS Early, prolonged antibiotic exposure among preterm infants may not lead to significant gastric dysrhythmia. Future studies including larger sample sizes and a "no antibiotic" exposure arm are essential in elucidating this potential relationship.
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Affiliation(s)
- Liane Samira Sadder
- Division of Pediatric Gastroenterology, Department of Pediatrics, UT Southwestern Medical Center, Dallas, Texas, USA
| | | | - Lindsay Roblyer
- Division of Neonatal-Perinatal Medicine, Department of Pediatrics, UT Southwestern Medical Center, Dallas, Texas, USA
| | - Rinarani Sanghavi
- Division of Pediatric Gastroenterology, Department of Pediatrics, UT Southwestern Medical Center, Dallas, Texas, USA
| | - Eric Brum Ortigoza
- Division of Neonatal-Perinatal Medicine, Department of Pediatrics, UT Southwestern Medical Center, Dallas, Texas, USA
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Camilleri M. Abnormal gastrointestinal motility is a major factor in explaining symptoms and a potential therapeutic target in patients with disorders of gut-brain interaction. Gut 2023; 72:2372-2380. [PMID: 37666657 PMCID: PMC10841318 DOI: 10.1136/gutjnl-2023-330542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Accepted: 08/23/2023] [Indexed: 09/06/2023]
Abstract
The objective of this article is to review the evidence of abnormal gastrointestinal (GI) tract motor functions in the context of disorders of gut-brain interaction (DGBI). These include abnormalities of oesophageal motility, gastric emptying, gastric accommodation, colonic transit, colonic motility, colonic volume and rectal evacuation. For each section regarding GI motor dysfunction, the article describes the preferred methods and the documented motor dysfunctions in DGBI based on those methods. The predominantly non-invasive measurements of gut motility as well as therapeutic interventions directed to abnormalities of motility suggest that such measurements are to be considered in patients with DGBI not responding to first-line approaches to behavioural or empirical dietary or pharmacological treatment.
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Affiliation(s)
- Michael Camilleri
- Clinical Enteric Neuroscience Translational and Epidemiological Research (C.E.N.T.E.R.), Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota, USA
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5
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Foong D, Calder S, Varghese C, Schamberg G, Xu W, Daker C, Ho V, Andrews CN, Gharibans AA, O’Grady G. Gastric Alimetry ® Test Interpretation in Gastroduodenal Disorders: Review and Recommendations. J Clin Med 2023; 12:6436. [PMID: 37892572 PMCID: PMC10607701 DOI: 10.3390/jcm12206436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Revised: 10/04/2023] [Accepted: 10/08/2023] [Indexed: 10/29/2023] Open
Abstract
Chronic gastroduodenal symptoms are prevalent worldwide, and there is a need for new diagnostic and treatment approaches. Several overlapping processes may contribute to these symptoms, including gastric dysmotility, hypersensitivity, gut-brain axis disorders, gastric outflow resistance, and duodenal inflammation. Gastric Alimetry® (Alimetry, New Zealand) is a non-invasive test for evaluating gastric function that combines body surface gastric mapping (high-resolution electrophysiology) with validated symptom profiling. Together, these complementary data streams enable important new clinical insights into gastric disorders and their symptom correlations, with emerging therapeutic implications. A comprehensive database has been established, currently comprising > 2000 Gastric Alimetry tests, including both controls and patients with various gastroduodenal disorders. From studies employing this database, this paper presents a systematic methodology for Gastric Alimetry test interpretation, together with an extensive supporting literature review. Reporting is grouped into four sections: Test Quality, Spectral Analysis, Symptoms, and Conclusions. This review compiles, assesses, and evaluates each of these aspects of test assessment, with discussion of relevant evidence, example cases, limitations, and areas for future work. The resultant interpretation methodology is recommended for use in clinical practice and research to assist clinicians in their use of Gastric Alimetry as a diagnostic aid and is expected to continue to evolve with further development.
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Affiliation(s)
- Daphne Foong
- School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia
| | - Stefan Calder
- Department of Surgery, Auckland City Hospital, Auckland 1023, New Zealand
- Alimetry Ltd., Auckland 1010, New Zealand
- Auckland Bioengineering Institute, University of Auckland, Auckland 1010, New Zealand
| | - Chris Varghese
- Department of Surgery, Auckland City Hospital, Auckland 1023, New Zealand
| | - Gabriel Schamberg
- Alimetry Ltd., Auckland 1010, New Zealand
- Auckland Bioengineering Institute, University of Auckland, Auckland 1010, New Zealand
| | - William Xu
- Department of Surgery, Auckland City Hospital, Auckland 1023, New Zealand
| | - Charlotte Daker
- Department of Gastroenterology, North Shore Hospital, Auckland 0620, New Zealand
| | - Vincent Ho
- School of Medicine, Western Sydney University, Campbelltown, NSW 2560, Australia
- Department of Gastroenterology and Hepatology, Campbelltown Hospital, Sydney, NSW 2560, Australia
| | - Christopher N. Andrews
- Division of Gastroenterology, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 1N4, Canada
| | - Armen A. Gharibans
- Department of Surgery, Auckland City Hospital, Auckland 1023, New Zealand
- Alimetry Ltd., Auckland 1010, New Zealand
- Auckland Bioengineering Institute, University of Auckland, Auckland 1010, New Zealand
| | - Greg O’Grady
- Department of Surgery, Auckland City Hospital, Auckland 1023, New Zealand
- Alimetry Ltd., Auckland 1010, New Zealand
- Auckland Bioengineering Institute, University of Auckland, Auckland 1010, New Zealand
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6
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O'Grady G, Varghese C, Schamberg G, Calder S, Du P, Xu W, Tack J, Daker C, Mousa H, Abell TL, Parkman HP, Ho V, Bradshaw LA, Hobson A, Andrews CN, Gharibans AA. Principles and clinical methods of body surface gastric mapping: Technical review. Neurogastroenterol Motil 2023; 35:e14556. [PMID: 36989183 PMCID: PMC10524901 DOI: 10.1111/nmo.14556] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 01/29/2023] [Accepted: 02/12/2023] [Indexed: 03/30/2023]
Abstract
BACKGROUND AND PURPOSE Chronic gastric symptoms are common, however differentiating specific contributing mechanisms in individual patients remains challenging. Abnormal gastric motility is present in a significant subgroup, but reliable methods for assessing gastric motor function in clinical practice are lacking. Body surface gastric mapping (BSGM) is a new diagnostic aid, employs multi-electrode arrays to measure and map gastric myoelectrical activity non-invasively in high resolution. Clinical adoption of BSGM is currently expanding following studies demonstrating the ability to achieve specific patient subgrouping, and subsequent regulatory clearances. An international working group was formed in order to standardize clinical BSGM methods, encompassing a technical group developing BSGM methods and a clinical advisory group. The working group performed a technical literature review and synthesis focusing on the rationale, principles, methods, and clinical applications of BSGM, with secondary review by the clinical group. The principles and validation of BSGM were evaluated, including key advances achieved over legacy electrogastrography (EGG). Methods for BSGM were reviewed, including device design considerations, patient preparation, test conduct, and data processing steps. Recent advances in BSGM test metrics and reference intervals are discussed, including four novel metrics, being the 'principal gastric frequency', BMI-adjusted amplitude, Gastric Alimetry Rhythm Index™, and fed: fasted amplitude ratio. An additional essential element of BSGM has been the introduction of validated digital tools for standardized symptom profiling, performed simultaneously during testing. Specific phenotypes identifiable by BSGM and the associated symptom profiles were codified with reference to pathophysiology. Finally, knowledge gaps and priority areas for future BSGM research were also identified by the working group.
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Affiliation(s)
- Gregory O'Grady
- Department of Surgery, The University of Auckland, Auckland, New Zealand
- Alimetry Ltd, Auckland, New Zealand
- Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand
| | - Chris Varghese
- Department of Surgery, The University of Auckland, Auckland, New Zealand
| | - Gabriel Schamberg
- Department of Surgery, The University of Auckland, Auckland, New Zealand
- Alimetry Ltd, Auckland, New Zealand
| | | | - Peng Du
- Alimetry Ltd, Auckland, New Zealand
- Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand
| | - William Xu
- Department of Surgery, The University of Auckland, Auckland, New Zealand
| | - Jan Tack
- Department of Gastroenterology, University Hospitals, Leuven, Belgium
| | | | - Hayat Mousa
- Division of Gastroenterology, Lustgarten Motility Center, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Thomas L Abell
- Division of Gastroenterology, Hepatology and Nutrition, University of Louisville, Louisville, Kentucky, USA
| | - Henry P Parkman
- Department of Medicine, Temple University Hospital, Philadelphia, Pennsylvania, USA
| | - Vincent Ho
- Western Sydney University, Sydney, New South Wales, Australia
| | | | | | - Christopher N Andrews
- Division of Gastroenterology and Hepatology, University of Calgary, Calgary, Alberta, Canada
| | - Armen A Gharibans
- Department of Surgery, The University of Auckland, Auckland, New Zealand
- Alimetry Ltd, Auckland, New Zealand
- Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand
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7
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Schamberg G, Calder S, Varghese C, Xu W, Wang WJ, Ho V, Daker C, Andrews CN, O'Grady G, Gharibans AA. Comparison of Gastric Alimetry ® body surface gastric mapping versus electrogastrography spectral analysis. Sci Rep 2023; 13:14987. [PMID: 37696955 PMCID: PMC10495352 DOI: 10.1038/s41598-023-41645-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Accepted: 08/29/2023] [Indexed: 09/13/2023] Open
Abstract
Electrogastrography (EGG) non-invasively evaluates gastric motility but is viewed as lacking clinical utility. Gastric Alimetry® is a new diagnostic test that combines high-resolution body surface gastric mapping (BSGM) with validated symptom profiling, with the goal of overcoming EGG's limitations. This study directly compared EGG and BSGM to define performance differences in spectral analysis. Comparisons between Gastric Alimetry BSGM and EGG were conducted by protocolized retrospective evaluation of 178 subjects [110 controls; 68 nausea and vomiting (NVS) and/or type 1 diabetes (T1D)]. Comparisons followed standard methodologies for each test (pre-processing, post-processing, analysis), with statistical evaluations for group-level differences, symptom correlations, and patient-level classifications. BSGM showed substantially tighter frequency ranges vs EGG in controls. Both tests detected rhythm instability in NVS, but EGG showed opposite frequency effects in T1D. BSGM showed an 8× increase in the number of significant correlations with symptoms. BSGM accuracy for patient-level classification was 0.78 for patients vs controls and 0.96 as compared to blinded consensus panel; EGG accuracy was 0.54 and 0.43. EGG detected group-level differences in patients, but lacked symptom correlations and showed poor accuracy for patient-level classification, explaining EGG's limited clinical utility. BSGM demonstrated substantial performance improvements across all domains.
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Affiliation(s)
- Gabriel Schamberg
- Department of Surgery, The University of Auckland, Auckland, New Zealand
- Alimetry Ltd, Auckland, New Zealand
| | - Stefan Calder
- Department of Surgery, The University of Auckland, Auckland, New Zealand
- Alimetry Ltd, Auckland, New Zealand
| | - Chris Varghese
- Department of Surgery, The University of Auckland, Auckland, New Zealand
| | - William Xu
- Department of Surgery, The University of Auckland, Auckland, New Zealand
| | - William Jiaen Wang
- School of Medicine, Western Sydney University, Sydney, Australia
- Department of Gastroenterology and Hepatology, Campbelltown Hospital, Sydney, Australia
- Department of Gastroenterology and Hepatology, Townsville University Hospital, Townsville, Australia
- Department of Gastroenterology and Hepatology, Princess Alexandra Hospital, Brisbane, Australia
| | - Vincent Ho
- School of Medicine, Western Sydney University, Sydney, Australia
- Department of Gastroenterology and Hepatology, Campbelltown Hospital, Sydney, Australia
| | - Charlotte Daker
- Department of Gastroenterology, North Shore Hospital, Auckland, New Zealand
| | | | - Greg O'Grady
- Department of Surgery, The University of Auckland, Auckland, New Zealand
- Alimetry Ltd, Auckland, New Zealand
- Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand
| | - Armen A Gharibans
- Department of Surgery, The University of Auckland, Auckland, New Zealand.
- Alimetry Ltd, Auckland, New Zealand.
- Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand.
- Perelman School of Medicine, University of Pennsylvania, Pennsylvania, United States.
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8
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Xu W, Gharibans AA, Calder S, Schamberg G, Walters A, Jang J, Varghese C, Carson D, Daker C, Waite S, Andrews CN, Cundy T, O’Grady G. Defining and Phenotyping Gastric Abnormalities in Long-Term Type 1 Diabetes Using a Novel Body Surface Gastric Mapping Device. GASTRO HEP ADVANCES 2023; 2:1120-1132. [PMID: 39131562 PMCID: PMC11307485 DOI: 10.1016/j.gastha.2023.08.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Accepted: 08/04/2023] [Indexed: 08/13/2024]
Abstract
Background and Aims Diabetic gastroenteropathy is associated with poor glycemic control and morbidity in people with type 1 diabetes (T1D). There is a lack of noninvasive techniques to assess and monitor gastric abnormalities. We aimed to define phenotypes of gastric myoelectrical abnormalities in people with longstanding T1D with and without symptoms using a novel noninvasive body surface gastric mapping (BSGM) device. Methods BSGM was performed on people with T1D of >10 years duration and matched controls, employing Gastric Alimetry (Alimetry, New Zealand), comprising of a high-resolution 64-channel array, validated symptom-logging App, and wearable reader. Results Thirty-two people with T1D were recruited (15 with a high symptom burden), and 32 controls. Those with symptoms showed more unstable gastric myoelectrical activity (Gastric Alimetry Rhythm Index 0.39 vs 0.51, P = .017; and lower average spatial covariance 0.48 vs 0.51, P = .009) compared with controls. Symptomatic patients also had a higher prevalence of peripheral neuropathy (67% vs 6%, P = .001), anxiety/depression diagnoses (27% vs 0%, P = .001), and higher mean hemoglobin A1C levels (76 vs 56 mmol/mol, P < .001). BSGM defined distinct phenotypes in T1D participants including those with markedly unstable gastric rhythms (4/32, 12.5%) and abnormally high gastric frequencies (9/32, 28%). Deviation in gastric frequency was positively correlated with symptoms of bloating, upper gut pain, nausea and vomiting, and fullness (R > 0.35, P < .05). Conclusion Gastric symptoms in people with longstanding T1D correlate with myoelectrical abnormalities on BSGM evaluation, in addition to glycemic control, psychological comorbidities, and peripheral neuropathy. BSGM using Gastric Alimetry identified a range of myoelectrical phenotypes, presenting targets for diagnosis, monitoring, and therapy.
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Affiliation(s)
- William Xu
- Department of Surgery, The University of Auckland, Auckland, New Zealand
| | - Armen A. Gharibans
- Department of Surgery, The University of Auckland, Auckland, New Zealand
- Alimetry Ltd, Auckland, New Zealand
- Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand
| | - Stefan Calder
- Department of Surgery, The University of Auckland, Auckland, New Zealand
- Alimetry Ltd, Auckland, New Zealand
| | - Gabriel Schamberg
- Department of Surgery, The University of Auckland, Auckland, New Zealand
- Alimetry Ltd, Auckland, New Zealand
| | - Anthony Walters
- Liggins Institute, University of Auckland, Auckland, New Zealand
| | - Jia Jang
- Department of Surgery, The University of Auckland, Auckland, New Zealand
| | - Chris Varghese
- Department of Surgery, The University of Auckland, Auckland, New Zealand
| | - Daniel Carson
- Department of Surgery, The University of Auckland, Auckland, New Zealand
| | - Charlotte Daker
- Alimetry Ltd, Auckland, New Zealand
- Department of Gastroenterology, North Shore Hospital, Te Whatu Ora Waitemata, New Zealand
| | | | - Christopher N. Andrews
- Alimetry Ltd, Auckland, New Zealand
- Department of Gastroenterology, University of Calgary, Calgary, Canada
| | - Tim Cundy
- Department of Medicine, University of Auckland, Auckland, New Zealand
| | - Gregory O’Grady
- Department of Surgery, The University of Auckland, Auckland, New Zealand
- Alimetry Ltd, Auckland, New Zealand
- Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand
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9
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Sebaratnam G, Law M, Broadbent E, Gharibans AA, Andrews CN, Daker C, O’Grady G, Calder S, Keane C. It's a helluva journey: a qualitative study of patient and clinician experiences of nausea and vomiting syndromes. Front Psychol 2023; 14:1232871. [PMID: 37637892 PMCID: PMC10457000 DOI: 10.3389/fpsyg.2023.1232871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Accepted: 07/17/2023] [Indexed: 08/29/2023] Open
Abstract
Background Chronic gastroduodenal disorders including, chronic nausea and vomiting syndrome, gastroparesis, and functional dyspepsia, are challenging to diagnose and manage. The diagnostic and treatment pathways for these disorders are complex, costly and overlap substantially; however, experiences of this pathway have not been thoroughly investigated. This study therefore aimed to explore clinician and patient perspectives on the current clinical pathway. Methods Semi-structured interviews were conducted between June 2020 and June 2022 with 11 patients with chronic nausea and vomiting syndrome alone (based on Rome IV criteria) and nine gastroenterologists who treat these conditions. Interviews were recorded, transcribed, and thematically analyzed using a reflexive, iterative, inductive approach. Five key patient themes were identified: (1) the impacts of their chronic gastroduodenal symptoms, (2) the complexity of the clinical journey, (3) their interactions with healthcare providers, (4) the need for advocacy, and (5) their experience of treatments. Five key clinician themes were also identified: (1) these conditions were seen as clinically complex, (2) there is an uncertain and variable clinical pathway, (3) the nuance of investigations, (4) these conditions were difficult to therapeutically manage, and (5) there are barriers to developing a therapeutic relationship. Conclusion Findings indicate that both patients and clinicians are dissatisfied with the current clinical care pathways for nausea and vomiting syndromes. Recommendations included the development of more clinically relevant and discriminant tests, standardization of the diagnostic journey, and the adoption of a multidisciplinary approach to diagnosis and treatment.
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Affiliation(s)
| | - Mikaela Law
- Alimetry Ltd., Auckland, New Zealand
- The Department of Surgery, The University of Auckland, Auckland, New Zealand
| | - Elizabeth Broadbent
- The Department of Psychological Medicine, The University of Auckland, Auckland, New Zealand
| | - Armen A. Gharibans
- Alimetry Ltd., Auckland, New Zealand
- The Department of Surgery, The University of Auckland, Auckland, New Zealand
| | - Christopher N. Andrews
- Alimetry Ltd., Auckland, New Zealand
- The Division of Gastroenterology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Charlotte Daker
- The Department of Gastroenterology, Waitematā District Health Board, Auckland, New Zealand
| | - Greg O’Grady
- Alimetry Ltd., Auckland, New Zealand
- The Department of Surgery, The University of Auckland, Auckland, New Zealand
| | - Stefan Calder
- Alimetry Ltd., Auckland, New Zealand
- The Department of Surgery, The University of Auckland, Auckland, New Zealand
| | - Celia Keane
- The Department of Surgery, The University of Auckland, Auckland, New Zealand
- The Department of Surgery, Northland District Health Board, Whangārei, New Zealand
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10
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Aghababaie Z, Wang THH, Nisbet LA, Matthee A, Dowrick J, Sands GB, Paskaranandavadivel N, Cheng LK, O'Grady G, Angeli-Gordon TR. Anaesthesia by intravenous propofol reduces the incidence of intra-operative gastric electrical slow-wave dysrhythmias compared to isoflurane. Sci Rep 2023; 13:11824. [PMID: 37479717 PMCID: PMC10362009 DOI: 10.1038/s41598-023-38612-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Accepted: 07/11/2023] [Indexed: 07/23/2023] Open
Abstract
Gastric motility is coordinated by bioelectrical slow-wave activity, and abnormal electrical dysrhythmias have been associated with nausea and vomiting. Studies have often been conducted under general anaesthesia, while the impact of general anaesthesia on slow-wave activity has not been studied. Clinical studies have shown that propofol anaesthesia reduces postoperative nausea and vomiting (PONV) compared with isoflurane, while the underlying mechanisms remain unclear. In this study, we investigated the effects of two anaesthetic drugs, intravenous (IV) propofol and volatile isoflurane, on slow-wave activity. In vivo experiments were performed in female weaner pigs (n = 24). Zolazepam and tiletamine were used to induce general anaesthesia, which was maintained using either IV propofol (n = 12) or isoflurane (n = 12). High-resolution electrical mapping of slow-wave activity was performed. Slow-wave dysrhythmias occurred less often in the propofol group, both in the duration of the recorded period that was dysrhythmic (propofol 14 ± 26%, isoflurane 43 ± 39%, P = 0.043 (Mann-Whitney U test)), and in a case-by-case basis (propofol 3/12, isoflurane 8/12, P = 0.015 (Chi-squared test)). Slow-wave amplitude was similar, while velocity and frequency were higher in the propofol group than the isoflurane group (P < 0.001 (Student's t-test)). This study presents a potential physiological biomarker linked to recent observations of reduced PONV with IV propofol. The results suggest that propofol is a more suitable anaesthetic for studying slow-wave patterns in vivo.
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Affiliation(s)
- Zahra Aghababaie
- Auckland Bioengineering Institute, University of Auckland, Private Bag 92019, Auckland, New Zealand
| | - Tim Hsu-Han Wang
- Department of Surgery, University of Auckland, Auckland, New Zealand
| | - Linley A Nisbet
- Auckland Bioengineering Institute, University of Auckland, Private Bag 92019, Auckland, New Zealand
| | - Ashton Matthee
- Auckland Bioengineering Institute, University of Auckland, Private Bag 92019, Auckland, New Zealand
| | - Jarrah Dowrick
- Auckland Bioengineering Institute, University of Auckland, Private Bag 92019, Auckland, New Zealand
| | - Gregory B Sands
- Auckland Bioengineering Institute, University of Auckland, Private Bag 92019, Auckland, New Zealand
| | | | - Leo K Cheng
- Auckland Bioengineering Institute, University of Auckland, Private Bag 92019, Auckland, New Zealand
| | - Gregory O'Grady
- Auckland Bioengineering Institute, University of Auckland, Private Bag 92019, Auckland, New Zealand
- Department of Surgery, University of Auckland, Auckland, New Zealand
| | - Timothy R Angeli-Gordon
- Auckland Bioengineering Institute, University of Auckland, Private Bag 92019, Auckland, New Zealand.
- Department of Surgery, University of Auckland, Auckland, New Zealand.
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11
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Ji S, Li B, Zhu C, Jiang G, Tang Y, Chen L. Risk assessment model for sleep disturbance based on gastrointestinal myoelectrical activity in middle-aged and elderly people. Front Psychiatry 2023; 14:1183108. [PMID: 37426096 PMCID: PMC10327604 DOI: 10.3389/fpsyt.2023.1183108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Accepted: 06/05/2023] [Indexed: 07/11/2023] Open
Abstract
Background Sleep disturbance has become a considerable factor affecting the quality of life for middle-aged and elderly people; however, there are still many obstacles to screening sleep disturbance for those people. Given the growing awareness of the association between gastrointestinal function and sleep disturbance, our study aims to predict the risk of sleep disturbance using gastrointestinal electrophysiological signals. Methods The Pittsburgh Sleep Quality Index and gastrointestinal electrophysiological signals of 914 participants in western China were used to establish the model. Demographic characteristics and routine blood test were collected as covariates. Participants were randomly assigned into two sets with a 7:3 ratio for training and validation. In the training set, the least absolute shrinkage and selection operator (LASSO) regression and stepwise logistic regression were used, respectively for variables selection and optimization. To assess the model performance, receiver operator characteristic (ROC) curve, calibration curve and decision curve analysis (DCA) were utilized. Then, validation was performed. Results Thirteen predictors were chosen from 46 variables by LASSO regression. Then, age, gender, percentage of normal slow wave and electrical spreading rate on the pre-meal gastric channel, dominant power ratio on the post-meal gastric channel, coupling percent and dominant frequency on the post-meal intestinal channel were the seven predictors reserved by logistic regression. The area under ROC curve was 0.65 in the training set and 0.63 in the validation set, both exhibited moderate predictive ability. Furthermore, by overlapping the DCA results of two data-sets, there might be clinical net benefit if 0.35 was used as reference threshold for high risk of sleep disturbance. Conclusion The model performs a worthy predictive potency for sleep disturbance, which not only provides clinical evidence for the association of gastrointestinal function with sleep disturbance, but also can be considered as an auxiliary assessment for screening sleep disturbance.
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Affiliation(s)
- Shuming Ji
- Department of Clinical Research Management, West China Hospital, Sichuan University, Chengdu, China
| | - Baichuan Li
- Department of Neurology, Joint Research Institution of Altitude Health, West China Hospital, Sichuan University, Chengdu, China
| | - Chenxing Zhu
- Department of Clinical Research Management, West China Hospital, Sichuan University, Chengdu, China
| | - Guohui Jiang
- Department of Neurology, Affiliated Hospital of North Sichuan Medical College, Nanchong, Sichuan, China
| | - Yusha Tang
- Department of Neurology, Joint Research Institution of Altitude Health, West China Hospital, Sichuan University, Chengdu, China
| | - Lei Chen
- Department of Neurology, Joint Research Institution of Altitude Health, West China Hospital, Sichuan University, Chengdu, China
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12
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Varghese C, Schamberg G, Calder S, Waite S, Carson D, Foong D, Wang WJ, Ho V, Woodhead J, Daker C, Xu W, Du P, Abell TL, Parkman HP, Tack J, Andrews CN, O'Grady G, Gharibans AA. Normative Values for Body Surface Gastric Mapping Evaluations of Gastric Motility Using Gastric Alimetry: Spectral Analysis. Am J Gastroenterol 2023; 118:1047-1057. [PMID: 36534985 DOI: 10.14309/ajg.0000000000002077] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 10/06/2022] [Indexed: 06/02/2023]
Abstract
INTRODUCTION Body surface gastric mapping (BSGM) is a new noninvasive test of gastric function. BSGM offers several novel and improved biomarkers of gastric function capable of differentiating patients with overlapping symptom profiles. The aim of this study was to define normative reference intervals for BSGM spectral metrics in a population of healthy controls. METHODS BSGM was performed in healthy controls using Gastric Alimetry (Alimetry, New Zealand) comprising a stretchable high-resolution array (8 × 8 electrodes; 196 cm 2 ), wearable Reader, and validated symptom-logging App. The evaluation encompassed a fasting baseline (30 minutes), 482 kCal meal, and 4-hour postprandial recording. Normative reference intervals were calculated for BSGM metrics including the Principal Gastric Frequency, Gastric Alimetry Rhythm Index (a measure of the concentration of power in the gastric frequency band over time), body mass index (BMI)-adjusted amplitude (μV), and fed:fasted amplitude ratio. Data were reported as median and reference interval (5th and/or 95th percentiles). RESULTS A total of 110 subjects (55% female, median age 32 years [interquartile range 24-50], median BMI 23.8 kg/m 2 [interquartile range 21.4-26.9]) were included. The median Principal Gastric Frequency was 3.04 cycles per minute; reference interval: 2.65-3.35 cycles per minute. The median Gastric Alimetry Rhythm Index was 0.50; reference interval: ≥0.25. The median BMI-adjusted amplitude was 37.6 μV; reference interval: 20-70 μV. The median fed:fasted amplitude ratio was 1.85; reference interval ≥1.08. A higher BMI was associated with a shorter meal-response duration ( P = 0.014). DISCUSSION This study provides normative reference intervals for BSGM spectral data to inform diagnostic interpretations of abnormal gastric function.
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Affiliation(s)
- Chris Varghese
- Department of Surgery, The University of Auckland, Auckland, New Zealand
| | - Gabriel Schamberg
- Department of Surgery, The University of Auckland, Auckland, New Zealand
- Alimetry, Auckland, New Zealand
| | - Stefan Calder
- Department of Surgery, The University of Auckland, Auckland, New Zealand
- Alimetry, Auckland, New Zealand
| | | | - Daniel Carson
- Department of Surgery, The University of Auckland, Auckland, New Zealand
| | | | | | - Vincent Ho
- Western Sydney University, Sydney, Australia
| | | | | | - William Xu
- Department of Surgery, The University of Auckland, Auckland, New Zealand
| | - Peng Du
- Alimetry, Auckland, New Zealand
- Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand
| | - Thomas L Abell
- Division of Gastroenterology, Hepatology and Nutrition, University of Louisville, Kentucky, USA
| | - Henry P Parkman
- Department of Medicine, Temple University Hospital, Philadelphia, Pennsylvania, USA
| | - Jan Tack
- Department of Gastroenterology, University Hospitals, Leuven, Belgium
| | | | - Gregory O'Grady
- Department of Surgery, The University of Auckland, Auckland, New Zealand
- Alimetry, Auckland, New Zealand
- Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand
| | - Armen A Gharibans
- Department of Surgery, The University of Auckland, Auckland, New Zealand
- Alimetry, Auckland, New Zealand
- Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand
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13
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Sintusek P, Mutalib M, Thapar N. Gastroesophageal reflux disease in children: What’s new right now? World J Gastrointest Endosc 2023; 15:84-102. [PMID: 37034973 PMCID: PMC10080553 DOI: 10.4253/wjge.v15.i3.84] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 01/15/2023] [Accepted: 02/08/2023] [Indexed: 03/16/2023] Open
Abstract
Gastroesophageal reflux (GER) in children is very common and refers to the involuntary passage of gastric contents into the esophagus. This is often physiological and managed conservatively. In contrast, GER disease (GERD) is a less common pathologic process causing troublesome symptoms, which may need medical management. Apart from abnormal transient relaxations of the lower esophageal sphincter, other factors that play a role in the pathogenesis of GERD include defects in esophageal mucosal defense, impaired esophageal and gastric motility and clearance, as well as anatomical defects of the lower esophageal reflux barrier such as hiatal hernia. The clinical manifestations of GERD in young children are varied and nonspecific prompting the necessity for careful diagnostic evaluation. Management should be targeted to the underlying aetiopathogenesis and to limit complications of GERD. The following review focuses on up-to-date information regarding of the pathogenesis, diagnostic evaluation and management of GERD in children.
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Affiliation(s)
- Palittiya Sintusek
- Thai Pediatric Gastroenterology, Hepatology and Immunology Research Unit (TPGHAI), Division of Gastroenterology, Department of Pediatrics, King Chulalongkorn Memorial Hospital and Thai Red Cross, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Bangkok, Thailand
| | - Mohamed Mutalib
- Department of Paediatric Gastroenterology, Pediatric and Gastroenterology Services, Evelina London Children’s Hospital, London SE1 7EH, United Kingdom
| | - Nikhil Thapar
- Department of Gastroenterology, Hepatology and Liver Transplant, Queensland Children’s Hospital, Brisbane, Queensland 4101, Australia
- School of Medicine, University of Queensland, Brisbane, Queensland 4006, Australia
- Woolworths Centre for Child Nutrition Research, Queensland University of Technology, Brisbane, Queensland 4101, Australia
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14
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Niang LY, Heckroth M, Mathur P, Abell TL. Gastroparesis syndromes: emerging drug targets and potential therapeutic opportunities. Expert Opin Investig Drugs 2023; 32:245-262. [PMID: 36872904 DOI: 10.1080/13543784.2023.2186222] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2023]
Abstract
INTRODUCTION Gastroparesis (Gp) and related disorders such as chronic unexplained nausea and vomiting and functional dyspepsia, known as gastropareis syndromes (GpS), have large unmet needs. Mainstays of GpS treatments are diet and drugs. AREAS COVERED The purpose of this review is to explore potential new medications and other therapies for gastroparesis. Before discussing possible new drugs, the currently used drugs are discussed. These include dopamine receptor antagonists, 5-hydroxytryptamine receptor agonists and antagonists, neurokinin-1 receptor antagonists and other anti-emetics. The article also considers future drugs that may be used for Gp, based on currently known pathophysiology. EXPERT OPINION Gaps in knowledge about the pathophysiology of gastroparesis and related syndromes are critical to developing therapeutic agents that will be successful. Recent major developments in the gastroparesis arena are related to microscopic anatomy, cellular function, and pathophysiology. The major challenges moving forward will be to develop the genetic and biochemical correlates of these major developments in gastroparesis research.
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Affiliation(s)
- Le Yu Niang
- Department of Gastroenterology, Hepatology and Nutrition, University of Louisville, Louisville, Kentucky, USA
| | - Matthew Heckroth
- Department of Medicine, University of Louisville, Louisville, Kentucky, USA
| | - Prateek Mathur
- Department of Gastroenterology, Hepatology and Nutrition, University of Louisville, Louisville, Kentucky, USA
| | - Thomas L Abell
- Department of Gastroenterology, Hepatology and Nutrition, University of Louisville, Louisville, Kentucky, USA
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15
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Schamberg G, Varghese C, Calder S, Waite S, Erickson J, O'Grady G, Gharibans AA. Revised spectral metrics for body surface measurements of gastric electrophysiology. Neurogastroenterol Motil 2023; 35:e14491. [PMID: 36409749 DOI: 10.1111/nmo.14491] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 10/17/2022] [Accepted: 10/21/2022] [Indexed: 11/22/2022]
Abstract
BACKGROUND Electrogastrography (EGG) non-invasively evaluates gastric function but has not achieved common clinical adoption due to several technical limitations. Body Surface Gastric Mapping (BSGM) has been introduced to overcome these limitations, but pitfalls in traditional metrics used to analyze spectral data remain unaddressed. This study critically evaluates five traditional EGG metrics and introduces improved BSGM spectral metrics, with validation in a large cohort. METHODS Pitfalls in five EGG metrics were assessed (dominant frequency, percentage time normogastria, amplitude, power ratio, and instability coefficient), leading to four revised BSGM spectral metrics. Traditional and revised metrics were compared to validate performance using a standardized 100-subject database of BSGM tests (30 min baseline; 4-h postprandial) recorded using Gastric Alimetry® (Alimetry). KEY RESULTS BMI and amplitude were highly correlated (r = -0.57, p < 0.001). We applied a conservative BMI correction to obtain a BMI-adjusted amplitude metric (r = -0.21, p = 0.037). Instability coefficient was highly correlated with both dominant frequency (r = -0.44, p < 0.001), and percent bradygastria (r = 0.85, p < 0.001), in part due to misclassification of low frequency transients as gastric activity. This was corrected by introducing distinct gastric frequency and stability metrics (Principal Gastric Frequency and Gastric Alimetry Rhythm Index (GA-RI)TM ) that were uncorrelated (r = 0.14, p = 0.314). Only 28% of subjects showed a maximal averaged amplitude within the first postprandial hour. Calculating Fed:Fasted Amplitude Ratio over a 4-h postprandial window yielded a median increase of 0.31 (IQR 0-0.64) above the traditional ratio. CONCLUSIONS & INFERENCES The revised metrics resolve critical pitfalls impairing the performance of traditional EGG, and should be applied in future BSGM spectral analyses.
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Affiliation(s)
- Gabriel Schamberg
- Alimetry Ltd, Auckland, New Zealand.,Department of Surgery, The University of Auckland, Auckland, New Zealand
| | - Chris Varghese
- Department of Surgery, The University of Auckland, Auckland, New Zealand
| | - Stefan Calder
- Alimetry Ltd, Auckland, New Zealand.,Department of Surgery, The University of Auckland, Auckland, New Zealand
| | | | | | - Greg O'Grady
- Alimetry Ltd, Auckland, New Zealand.,Department of Surgery, The University of Auckland, Auckland, New Zealand.,Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand
| | - Armen A Gharibans
- Alimetry Ltd, Auckland, New Zealand.,Department of Surgery, The University of Auckland, Auckland, New Zealand.,Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand
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16
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Gharibans AA, Hayes TCL, Carson DA, Calder S, Varghese C, Du P, Yarmut Y, Waite S, Keane C, Woodhead JST, Andrews CN, O'Grady G. A novel scalable electrode array and system for non-invasively assessing gastric function using flexible electronics. Neurogastroenterol Motil 2023; 35:e14418. [PMID: 35699340 PMCID: PMC10078595 DOI: 10.1111/nmo.14418] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 03/29/2022] [Accepted: 05/05/2022] [Indexed: 02/02/2023]
Abstract
BACKGROUND Disorders of gastric function are highly prevalent, but diagnosis often remains symptom-based and inconclusive. Body surface gastric mapping is an emerging diagnostic solution, but current approaches lack scalability and are cumbersome and clinically impractical. We present a novel scalable system for non-invasively mapping gastric electrophysiology in high-resolution (HR) at the body surface. METHODS The system comprises a custom-designed stretchable high-resolution "peel-and-stick" sensor array (8 × 8 pre-gelled Ag/AgCl electrodes at 2 cm spacing; area 225 cm2 ), wearable data logger with custom electronics incorporating bioamplifier chips, accelerometer and Bluetooth synchronized in real-time to an App with cloud connectivity. Automated algorithms filter and extract HR biomarkers including propagation (phase) mapping. The system was tested in a cohort of 24 healthy subjects to define reliability and characterize features of normal gastric activity (30 m fasting, standardized meal, and 4 h postprandial). KEY RESULTS Gastric mapping was successfully achieved non-invasively in all cases (16 male; 8 female; aged 20-73 years; BMI 24.2 ± 3.5). In all subjects, gastric electrophysiology and meal responses were successfully captured and quantified non-invasively (mean frequency 2.9 ± 0.3 cycles per minute; peak amplitude at mean 60 m postprandially with return to baseline in <4 h). Spatiotemporal mapping showed regular and consistent wave activity of mean direction 182.7° ± 73 (74.7% antegrade, 7.8% retrograde, 17.5% indeterminate). CONCLUSIONS AND INFERENCES BSGM is a new diagnostic tool for assessing gastric function that is scalable and ready for clinical applications, offering several biomarkers that are improved or new to gastroenterology practice.
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Affiliation(s)
- Armen A Gharibans
- Department of Surgery, University of Auckland, Auckland, New Zealand.,Alimetry Ltd, Auckland, New Zealand.,Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | - Tommy C L Hayes
- Department of Surgery, University of Auckland, Auckland, New Zealand
| | - Daniel A Carson
- Department of Surgery, University of Auckland, Auckland, New Zealand
| | | | - Chris Varghese
- Department of Surgery, University of Auckland, Auckland, New Zealand
| | - Peng Du
- Alimetry Ltd, Auckland, New Zealand.,Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | | | | | - Celia Keane
- Department of Surgery, University of Auckland, Auckland, New Zealand.,Alimetry Ltd, Auckland, New Zealand
| | - Jonathan S T Woodhead
- Alimetry Ltd, Auckland, New Zealand.,Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland, Auckland, New Zealand
| | - Christopher N Andrews
- Alimetry Ltd, Auckland, New Zealand.,Department of Medicine, University of Calgary, NB Calgary, Alberta, Canada
| | - Greg O'Grady
- Department of Surgery, University of Auckland, Auckland, New Zealand.,Alimetry Ltd, Auckland, New Zealand
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17
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Murphey CP, Shulgach JA, Amin PR, Douglas NK, Bielanin JP, Sampson JT, Horn CC, Yates BJ. Physiological changes associated with copper sulfate-induced nausea and retching in felines. Front Physiol 2023; 14:1077207. [PMID: 36744037 PMCID: PMC9892644 DOI: 10.3389/fphys.2023.1077207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Accepted: 01/11/2023] [Indexed: 01/20/2023] Open
Abstract
Nausea is a common disease symptom, yet there is no consensus regarding its physiological markers. In contrast, the process of vomiting is well documented as sequential muscular contractions of the diaphragm and abdominal muscles and esophageal shortening. Nausea, like other self-reported perceptions, is difficult to distinguish in preclinical models, but based on human experience emesis is usually preceded by nausea. Here we focused on measuring gastrointestinal and cardiorespiratory changes prior to emesis to provide additional insights into markers for nausea. Felines were instrumented to chronically record heart rate, respiration, and electromyographic (EMG) activity from the stomach and duodenum before and after intragastric delivery of saline or copper sulfate (CuSO4, from 83 to 322 mg). CuSO4 is a prototypical emetic test agent that triggers vomiting primarily by action on GI vagal afferent fibers when administered intragastrically. CuSO4 infusion elicited a significant increase in heart rate, decrease in respiratory rate, and a disruption of gastric and intestinal EMG activity several minutes prior to emesis. The change in EMG activity was most consistent in the duodenum. Administration of the same volume of saline did not induce these effects. Increasing the dose of CuSO4 did not alter the physiologic changes induced by the treatment. It is postulated that the intestinal EMG activity was related to the retrograde movement of chyme from the intestine to the stomach demonstrated to occur prior to emesis by other investigators. These findings suggest that monitoring of intestinal EMG activity, perhaps in combination with heart rate, may provide the best indicator of the onset of nausea following treatments and in disease conditions, including GI disease, associated with emesis.
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Affiliation(s)
- Charles P. Murphey
- Department of Otolaryngology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States,Department of Neuroscience, University of Pittsburgh, Pittsburgh, PA, United States
| | - Jonathan A. Shulgach
- Department of Otolaryngology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States,Mechanical Engineering Department, Carnegie Mellon University, Pittsburgh, PA, United States
| | - Pooja R. Amin
- Department of Otolaryngology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Nerone K. Douglas
- Department of Otolaryngology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - John P. Bielanin
- Department of Otolaryngology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Jacob T. Sampson
- Department of Otolaryngology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Charles C. Horn
- UPMC Hillman Cancer Center, Pittsburgh, PA, United States,Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States,Department of Anesthesiology and Perioperative Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Bill J. Yates
- Department of Otolaryngology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States,Department of Neuroscience, University of Pittsburgh, Pittsburgh, PA, United States,*Correspondence: Bill J. Yates,
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18
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Han X, Zhu H. Endoscopic mucosal electrodes: New directions for recording and regulating gastric myoelectric activity. Front Surg 2023; 9:1035723. [PMID: 36684308 PMCID: PMC9852521 DOI: 10.3389/fsurg.2022.1035723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2022] [Accepted: 11/22/2022] [Indexed: 01/09/2023] Open
Abstract
With the gradual deepening of the study of gastric motility disorders, people increasingly realize that gastric myoelectric activity plays an important role in coordinating gastric function. This article introduces the advantages of endoscopic mucosal electrodes compared with traditional electrodes. Several different types of mucosal electrodes and how to fix the electrodes by endoscope are introduced. Endoscopic mucosal electrodes can record and regulate gastric myoelectric activity, which has great value in the study of gastric motility. Endoscopic mucosal electrode technique refers to the fixation of the electrode in the designated part of the gastric mucosa by endoscope. Through endoscopic mucosal electrodes, on the one hand, we can record gastric myoelectric activity, on the other hand, we can carry out gastric electrical stimulation to interfere with gastric rhythm. Endoscopic mucosal electrodes have higher accuracy than traditional cutaneous electrodes, less trauma and lower cost than serosal electrodes. Endoscopic mucosal electrodes have a good application prospect for diseases such as gastroparesis and obesity.
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19
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Sclocco R, Fisher H, Staley R, Han K, Mendez A, Bolender A, Coll-Font J, Kettner NW, Nguyen C, Kuo B, Napadow V. Cine gastric MRI reveals altered Gut-Brain Axis in Functional Dyspepsia: gastric motility is linked with brainstem-cortical fMRI connectivity. Neurogastroenterol Motil 2022; 34:e14396. [PMID: 35560690 PMCID: PMC9529794 DOI: 10.1111/nmo.14396] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 03/31/2022] [Accepted: 04/25/2022] [Indexed: 12/14/2022]
Abstract
BACKGROUND Functional dyspepsia (FD) is a disorder of gut-brain interaction, and its putative pathophysiology involves dysregulation of gastric motility and central processing of gastric afference. The vagus nerve modulates gastric peristalsis and carries afferent sensory information to brainstem nuclei, specifically the nucleus tractus solitarii (NTS). Here, we combine MRI assessment of gastric kinematics with measures of NTS functional connectivity to the brain in patients with FD and healthy controls (HC), in order to elucidate how gut-brain axis communication is associated with FD pathophysiology. METHODS Functional dyspepsia and HC subjects experienced serial gastric MRI and brain fMRI following ingestion of a food-based contrast meal. Gastric function indices estimated from 4D cine MRI data were compared between FD and HC groups using repeated measure ANOVA models, controlling for ingested volume. Brain connectivity of the NTS was contrasted between groups and associated with gastric function indices. KEY RESULTS Propagation velocity of antral peristalsis was significantly lower in FD compared to HC. The brain network defined by NTS connectivity loaded most strongly onto the Default Mode Network, and more strongly onto the Frontoparietal Network in FD. FD also demonstrated higher NTS connectivity to insula, anterior cingulate and prefrontal cortices, and pre-supplementary motor area. NTS connectivity was linked to propagation velocity in HC, but not FD, whereas peristalsis frequency was linked with NTS connectivity in patients with FD. CONCLUSIONS & INFERENCES Our multi-modal MRI approach revealed lower peristaltic propagation velocity linked to altered brainstem-cortical functional connectivity in patients suffering from FD suggesting specific plasticity in gut-brain communication.
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Affiliation(s)
- Roberta Sclocco
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital Radiology, Harvard Medical School, Charlestown, MA, USA
- Department of Radiology, Logan University, Chesterfield, MO, USA
| | - Harrison Fisher
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital Radiology, Harvard Medical School, Charlestown, MA, USA
| | - Rowan Staley
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital Radiology, Harvard Medical School, Charlestown, MA, USA
- Department of Gastroenterology and Center for Neurointestinal Health, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Kyungsun Han
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital Radiology, Harvard Medical School, Charlestown, MA, USA
- Korean Institute of Oriental Medicine, Daejeon, Korea
| | - April Mendez
- Department of Gastroenterology and Center for Neurointestinal Health, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Andrew Bolender
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital Radiology, Harvard Medical School, Charlestown, MA, USA
- Department of Gastroenterology and Center for Neurointestinal Health, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Jaume Coll-Font
- Cardiovascular Research Center, Massachusetts General Hospital, Charlestown, MA, USA
- Department of Medicine, Harvard Medical School, Massachusetts General Hospital, Charlestown, MA, USA
| | | | - Christopher Nguyen
- Cardiovascular Research Center, Massachusetts General Hospital, Charlestown, MA, USA
- Department of Medicine, Harvard Medical School, Massachusetts General Hospital, Charlestown, MA, USA
- Division of Health Sciences and Technology, Harvard-Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Braden Kuo
- Department of Gastroenterology and Center for Neurointestinal Health, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Vitaly Napadow
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital Radiology, Harvard Medical School, Charlestown, MA, USA
- Department of Radiology, Logan University, Chesterfield, MO, USA
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20
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Gharibans AA, Calder S, Varghese C, Waite S, Schamberg G, Daker C, Du P, Alighaleh S, Carson D, Woodhead J, Farrugia G, Windsor JA, Andrews CN, O'Grady G. Gastric dysfunction in patients with chronic nausea and vomiting syndromes defined by a noninvasive gastric mapping device. Sci Transl Med 2022; 14:eabq3544. [PMID: 36130019 PMCID: PMC10042458 DOI: 10.1126/scitranslmed.abq3544] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Chronic nausea and vomiting syndromes (NVSs) are prevalent and debilitating disorders. Putative mechanisms include gastric neuromuscular disease and dysregulation of brain-gut interaction, but clinical tests for objectively defining gastric motor function are lacking. A medical device enabling noninvasive body surface gastric mapping (BSGM) was developed and applied to evaluate NVS pathophysiology. BSGM was performed in 43 patients with NVS and 43 matched controls using Gastric Alimetry (Alimetry), a conformable high-resolution array (8 × 8 electrodes; 20-mm interelectrode spacing), wearable reader, and validated symptom-logging app. Continuous measurement encompassed a fasting baseline (30 minutes), 482-kilocalorie meal, and 4-hour postprandial recording, followed by spectral and spatial biomarker analyses. Meal responses were impaired in NVS, with reduced amplitudes compared to controls (median, 23.3 microvolts versus 38.0 microvolts, P < 0.001), impaired fed-fasting power ratios (1.1 versus 1.6, P = 0.02), and disorganized slow waves (spatial frequency stability, 13.6 versus 49.5; P < 0.001). Two distinct NVS subgroups were evident with indistinguishable symptoms (all P > 0.05). Most patients (62%) had normal BSGM studies with increased psychological comorbidities (43.5% versus 7.7%; P = 0.03) and anxiety scores (median, 16.5 versus 13.0; P = 0.035). A smaller subgroup (31%) had markedly abnormal BSGM, with biomarkers correlating with symptoms (nausea, pain, excessive fullness, early satiety, and bloating; all r > 0.35, P < 0.05). Patients with NVS share overlapping symptoms but comprise distinct underlying phenotypes as revealed by a BSGM device. These phenotypes correlate with symptoms, which should inform clinical management and therapeutic trial design.
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Affiliation(s)
- Armen A Gharibans
- Surgical and Translational Research Centre, University of Auckland, Auckland 1023, New Zealand.,Alimetry Ltd., Auckland 1010, New Zealand.,Auckland Bioengineering Institute, University of Auckland, Auckland 1010, New Zealand
| | - Stefan Calder
- Surgical and Translational Research Centre, University of Auckland, Auckland 1023, New Zealand.,Alimetry Ltd., Auckland 1010, New Zealand
| | - Chris Varghese
- Surgical and Translational Research Centre, University of Auckland, Auckland 1023, New Zealand
| | | | | | - Charlotte Daker
- Department of Gastroenterology, North Shore Hospital, Auckland 0620, New Zealand
| | - Peng Du
- Alimetry Ltd., Auckland 1010, New Zealand.,Auckland Bioengineering Institute, University of Auckland, Auckland 1010, New Zealand
| | | | - Daniel Carson
- Surgical and Translational Research Centre, University of Auckland, Auckland 1023, New Zealand
| | | | | | - John A Windsor
- Surgical and Translational Research Centre, University of Auckland, Auckland 1023, New Zealand
| | - Christopher N Andrews
- Division of Gastroenterology, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Greg O'Grady
- Surgical and Translational Research Centre, University of Auckland, Auckland 1023, New Zealand.,Alimetry Ltd., Auckland 1010, New Zealand.,Auckland Bioengineering Institute, University of Auckland, Auckland 1010, New Zealand
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21
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Aghababaie Z, Cheng LK, Paskaranandavadivel N, Avci R, Chan CHA, Matthee A, Amirapu S, Asirvatham SJ, Farrugia G, Beyder A, O’Grady G, Angeli-Gordon TR. Targeted ablation of gastric pacemaker sites to modulate patterns of bioelectrical slow wave activation and propagation in an anesthetized pig model. Am J Physiol Gastrointest Liver Physiol 2022; 322:G431-G445. [PMID: 35137624 PMCID: PMC8917929 DOI: 10.1152/ajpgi.00332.2021] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Gastric motility is coordinated by underlying bioelectrical slow waves. Gastric dysrhythmias occur in gastrointestinal (GI) motility disorders, but there are no validated methods for eliminating dysrhythmias. We hypothesized that targeted ablation could eliminate pacemaker sites in the stomach, including dysrhythmic ectopic pacemaker sites. In vivo high-resolution serosal electrical mapping (16 × 16 electrodes; 6 × 6 cm) was applied to localize normal and ectopic gastric pacemaker sites in 13 anesthetized pigs. Radiofrequency ablation was performed in a square formation surrounding the pacemaker site. Postablation high-resolution mapping revealed that ablation successfully induced localized conduction blocks after 18 min (SD 5). Normal gastric pacemaker sites were eliminated by ablation (n = 6), resulting in the emergence of a new pacemaker site immediately distal to the original site in all cases. Ectopic pacemaker sites were similarly eliminated by ablation in all cases (n = 7), and the surrounding mapped area was then entrained by normal antegrade activity in five of those cases. Histological analysis showed that ablation lesions extended through the entire depth of the muscle layer. Immunohistochemical staining confirmed localized interruption of the interstitial cell of Cajal (ICC) network through the ablation lesions. This study demonstrates that targeted gastric ablation can effectively modulate gastric electrical activation, including eliminating ectopic sites of slow wave activation underlying gastric dysrhythmias, without disrupting surrounding conduction capability or tissue structure. Gastric ablation presents a powerful new research tool for modulating gastric electrical activation and may likely hold therapeutic potential for disorders of gastric function.NEW & NOTEWORTHY This study presents gastric ablation as a novel tool for modulating gastric bioelectrical activation, including eliminating the normal gastric pacemaker site as well as abnormal ectopic pacemaker sites underlying gastric dysrhythmias. Targeted application of radiofrequency ablation was able to eliminate these pacemaker sites without disrupting surrounding conduction capability or tissue structure. Gastric ablation presents a powerful new research tool for modulating gastric electrical activation and may likely hold therapeutic potential for disorders of gastric function.
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Affiliation(s)
- Zahra Aghababaie
- 1Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | - Leo K. Cheng
- 1Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand,2Department of Surgery, Vanderbilt University, Nashville, Tennessee
| | | | - Recep Avci
- 1Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | | | - Ashton Matthee
- 1Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | - Satya Amirapu
- 3Histology Laboratory, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | | | - Gianrico Farrugia
- 5Division of Gastroenterology and Hepatology and Enteric Neurosciences Program, Mayo Clinic, Rochester, Minnesota
| | - Arthur Beyder
- 5Division of Gastroenterology and Hepatology and Enteric Neurosciences Program, Mayo Clinic, Rochester, Minnesota
| | - Gregory O’Grady
- 1Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand,6Department of Surgery, University of Auckland, Auckland, New Zealand
| | - Timothy R. Angeli-Gordon
- 1Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand,6Department of Surgery, University of Auckland, Auckland, New Zealand
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22
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Levinthal DJ. Slow Wave(s) of Enthusiasm: Electrogastrography as an Electrodiagnostic Tool in Clinical Gastroenterology. Dig Dis Sci 2022; 67:737-738. [PMID: 33956279 DOI: 10.1007/s10620-021-07029-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/20/2021] [Indexed: 12/09/2022]
Affiliation(s)
- David J Levinthal
- Department of Medicine, Division of Gastroenterology, Hepatology, and Nutrition, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA. .,, M2 C-Wing PUH, 200 Lothrop Street, Pittsburgh, PA, 15213, USA.
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23
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O'Grady G, Gharibans AA, Du P, Huizinga JD. The gastric conduction system in health and disease: a translational review. Am J Physiol Gastrointest Liver Physiol 2021; 321:G527-G542. [PMID: 34549598 DOI: 10.1152/ajpgi.00065.2021] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Gastric peristalsis is critically dependent on an underlying electrical conduction system. Recent years have witnessed substantial progress in clarifying the operations of this system, including its pacemaking units, its cellular architecture, and slow-wave propagation patterns. Advanced techniques have been developed for assessing its functions at high spatiotemporal resolutions. This review synthesizes and evaluates this progress, with a focus on human and translational physiology. A current conception of the initiation and conduction of slow-wave activity in the human stomach is provided first, followed by a detailed discussion of its organization at the cellular and tissue level. Particular emphasis is then given to how gastric electrical disorders may contribute to disease states. Gastric dysfunction continues to grow in their prevalence and impact, and while gastric dysrhythmia is established as a clear and pervasive feature in several major gastric disorders, its role in explaining pathophysiology and informing therapy is still emerging. New insights from high-resolution gastric mapping are evaluated, together with historical data from electrogastrography, and the physiological relevance of emerging biomarkers from body surface mapping such as retrograde propagating slow waves. Knowledge gaps requiring further physiological research are highlighted.
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Affiliation(s)
- Gregory O'Grady
- Department of Surgery, The University of Auckland, Auckland, New Zealand.,Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand
| | - Armen A Gharibans
- Department of Surgery, The University of Auckland, Auckland, New Zealand.,Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand
| | - Peng Du
- Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand
| | - Jan D Huizinga
- Department of Medicine, Farncombe Family Digestive Health Research Institute, McMaster University, Hamilton, Ontario, Canada
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