title: High-resolution electrical mapping of porcine gastric slow-wave propagation from the mucosal surface.
abstract: Gastric motility is coordinated by bioelectrical slow waves, and gastric dysrhythmias are reported in motility disorders. High-resolution (HR) mapping has advanced the accurate assessment of gastric dysrhythmias, offering promise as a diagnostic technique. However, HR mapping has been restricted to invasive surgical serosal access. This study investigates the feasibility of HR mapping from the gastric mucosal surface.
  
  
  
  Experiments were conducted in vivo in 14 weaner pigs. Reference serosal recordings were performed with flexible-printed-circuit (FPC) arrays (128-192 electrodes). Mucosal recordings were performed by two methods: (i) FPC array aligned directly opposite the serosal array, and (ii) cardiac mapping catheter modified for gastric mucosal recordings. Slow-wave propagation and morphology characteristics were quantified and compared between simultaneous serosal and mucosal recordings.
  
  
  
  Slow-wave activity was consistently recorded from the mucosal surface from both electrode arrays. Mucosally recorded slow-wave propagation was consistent with reference serosal activation pattern, frequency (P≥.3), and velocity (P≥.4). However, mucosally recorded slow-wave morphology exhibited reduced amplitude (65-72% reduced, P<.001) and wider downstroke width (18-31% wider, P≤.02), compared to serosal data. Dysrhythmias were successfully mapped and classified from the mucosal surface, accorded with serosal data, and were consistent with known dysrhythmic mechanisms in the porcine model.
  
  
  
  High-resolution gastric electrical mapping was achieved from the mucosal surface, and demonstrated consistent propagation characteristics with serosal data. However, mucosal signal morphology was attenuated, demonstrating necessity for optimized electrode designs and analytical algorithms. This study demonstrates feasibility of endoscopic HR mapping, providing a foundation for advancement of minimally invasive spatiotemporal gastric mapping as a clinical and scientific tool.
authors.affiliation: Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand.
authors.forename: T R
authors.initials: TR
authors.lastname: Angeli
authors.affiliation: Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand.
authors.forename: P
authors.initials: P
authors.lastname: Du
authors.affiliation: Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand.
authors.forename: N
authors.initials: N
authors.lastname: Paskaranandavadivel
authors.affiliation: Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand.
authors.forename: S
authors.initials: S
authors.lastname: Sathar
authors.affiliation: Department of Surgery, University of Auckland, Auckland, New Zealand.
authors.forename: A
authors.initials: A
authors.lastname: Hall
authors.affiliation: Division of Cardiovascular Diseases, Mayo Clinic, Rochester, MN, USA.
authors.forename: S J
authors.initials: SJ
authors.lastname: Asirvatham
authors.affiliation: Department of Gastroenterology and Hepatology, Mayo Clinic, Rochester, MN, USA.
authors.forename: G
authors.initials: G
authors.lastname: Farrugia
authors.affiliation: Department of Surgery, University of Auckland, Auckland, New Zealand.
authors.forename: J A
authors.initials: JA
authors.lastname: Windsor
authors.affiliation: Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand.|Department of Surgery, Vanderbilt University, Nashville, TN, USA.
authors.forename: L K
authors.initials: LK
authors.lastname: Cheng
authors.affiliation: Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand.|Department of Surgery, University of Auckland, Auckland, New Zealand.
authors.forename: G
authors.initials: G
authors.lastname: O'Grady
mesh_terms: D000818:Animals; D004566:Electrodes; D055724:Electrophysiological Phenomena; D004594:Electrophysiology / Q000295:instrumentation / Q000379:methods*; D005260:Female; D005769:Gastrointestinal Motility; D009092:Mucous Membrane / Q000502:physiology*; D012704:Serous Membrane / Q000502:physiology*; D012815:Signal Processing, Computer-Assisted; D013552:Swine
keywords: dysmotility; electrophysiology; endoscopy; motility; stomach