TY - JOUR
T1 - Functional physiology of the human terminal antrum defined by highresolution electrical mapping and computational modeling
AU - Berry, Rachel
AU - Miyagawa, Taimei
AU - Paskaranandavadivel, Niranchan
AU - Du, Peng
AU - Angeli, Timothy R.
AU - Trew, Mark L.
AU - Windsor, John A.
AU - Imai, Yohsuke
AU - O’Grady, Gregory
AU - Cheng, Leo K.
N1 - Funding Information:
This project and research team were funded by research grants from the New Zealand Health Research Council (HRC), the U.S. National Institutes of Health (R01 DK-64775), the Riddet Institute Centre of Research Excellence and the Medical Technologies Centre of Research Excellence (MedTech CoRE). R. Berry was supported by a Commonwealth Scholarship. L. Cheng was supported by a Fraunhofer-Bessel Research Award from the Alexander von Humboldt Foundation and the Fraunhofer IPA. P. Du was supported by a Rutherford Discovery Fellowship administered by the Royal Society of New Zealand. T. Miyagawa and Y. Imai were supported by JSPS KAKENHI grant numbers, 25000008, 26600151, 15J02376, and 16H03187.
Publisher Copyright:
© 2016 the American Physiological Society.
PY - 2016
Y1 - 2016
N2 - High-resolution (HR) mapping has been used to study gastric slowwave activation; however, the specific characteristics of antral electrophysiology remain poorly defined. This study applied HR mapping and computational modeling to define functional human antral physiology. HR mapping was performed in 10 subjects using flexible electrode arrays (128-192 electrodes; 16-24 cm2) arranged from the pylorus to mid-corpus. Anatomical registration was by photographs and anatomical landmarks. Slow-wave parameters were computed, and resultant data were incorporated into a computational fluid dynamics (CFD) model of gastric flow to calculate impact on gastric mixing. In all subjects, extracellular mapping demonstrated normal aboral slow-wave propagation and a region of increased amplitude and velocity in the prepyloric antrum. On average, the high-velocity region commenced 28 mm proximal to the pylorus, and activation ceased 6 mm from the pylorus. Within this region, velocity increased 0.2 mm/s per mm of tissue, from the mean 3.3 ± 0.1 mm/s to 7.5 ± 0.6 mm/s (P < 0.001), and extracellular amplitude increased from 1.5 ± 0.1 mV to 2.5 ± 0.1 mV (P < 0.001). CFD modeling using representative parameters quantified a marked increase in antral recirculation, resulting in an enhanced gastric mixing, due to the accelerating terminal antral contraction. The extent of gastric mixing increased almost linearly with the maximal velocity of the contraction. In conclusion, the human terminal antral contraction is controlled by a short region of rapid high-amplitude slow-wave activity. Distal antral wave acceleration plays a major role in antral flow and mixing, increasing particle strain and trituration.
AB - High-resolution (HR) mapping has been used to study gastric slowwave activation; however, the specific characteristics of antral electrophysiology remain poorly defined. This study applied HR mapping and computational modeling to define functional human antral physiology. HR mapping was performed in 10 subjects using flexible electrode arrays (128-192 electrodes; 16-24 cm2) arranged from the pylorus to mid-corpus. Anatomical registration was by photographs and anatomical landmarks. Slow-wave parameters were computed, and resultant data were incorporated into a computational fluid dynamics (CFD) model of gastric flow to calculate impact on gastric mixing. In all subjects, extracellular mapping demonstrated normal aboral slow-wave propagation and a region of increased amplitude and velocity in the prepyloric antrum. On average, the high-velocity region commenced 28 mm proximal to the pylorus, and activation ceased 6 mm from the pylorus. Within this region, velocity increased 0.2 mm/s per mm of tissue, from the mean 3.3 ± 0.1 mm/s to 7.5 ± 0.6 mm/s (P < 0.001), and extracellular amplitude increased from 1.5 ± 0.1 mV to 2.5 ± 0.1 mV (P < 0.001). CFD modeling using representative parameters quantified a marked increase in antral recirculation, resulting in an enhanced gastric mixing, due to the accelerating terminal antral contraction. The extent of gastric mixing increased almost linearly with the maximal velocity of the contraction. In conclusion, the human terminal antral contraction is controlled by a short region of rapid high-amplitude slow-wave activity. Distal antral wave acceleration plays a major role in antral flow and mixing, increasing particle strain and trituration.
KW - Computational fluid dynamics
KW - Electrophysiology
KW - Interstitial cell of Cajal
KW - Slow wave
KW - Stomach
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U2 - 10.1152/ajpgi.00255.2016
DO - 10.1152/ajpgi.00255.2016
M3 - Article
C2 - 27659422
AN - SCOPUS:84994681193
VL - 311
SP - G895-G902
JO - American Journal of Physiology - Gastrointestinal and Liver Physiology
JF - American Journal of Physiology - Gastrointestinal and Liver Physiology
SN - 0193-1857
IS - 5
ER -