scholarly journals High‐resolution optical mapping of gastric slow wave propagation

2018 ◽  
Vol 31 (1) ◽  
pp. e13449 ◽  
Author(s):  
Hanyu Zhang ◽  
Han Yu ◽  
Gregory P. Walcott ◽  
Niranchan Paskaranandavadivel ◽  
Leo K. Cheng ◽  
...  
Keyword(s):  
Wave Propagation ◽  
High Resolution ◽  
Slow Wave ◽  
Optical Mapping ◽  
Gastric Slow Wave

scholarly journals High-resolution mapping of gastric slow-wave recovery profiles: biophysical model, methodology, and demonstration of applications

2017 ◽  
Vol 313 (3) ◽  
pp. G265-G276 ◽  
Author(s):  
N. Paskaranandavadivel ◽  
L. K. Cheng ◽  
P. Du ◽  
J. M. Rogers ◽  
G. O’Grady
Keyword(s):  
Wave Propagation ◽  
Wavelet Transform ◽  
High Resolution ◽  
Slow Wave ◽  
Recovery Phase ◽  
Slow Waves ◽  
Gastric Slow Wave ◽  
High Resolution Mapping ◽  
Resolution Mapping ◽  
Extracellular Potentials

Slow waves play a central role in coordinating gastric motor activity. High-resolution mapping of extracellular potentials from the stomach provides spatiotemporal detail on normal and dysrhythmic slow-wave patterns. All mapping studies to date have focused exclusively on tissue activation; however, the recovery phase contains vital information on repolarization heterogeneity, the excitable gap, and refractory tail interactions but has not been investigated. Here, we report a method to identify the recovery phase in slow-wave mapping data. We first developed a mathematical model of unipolar extracellular potentials that result from slow-wave propagation. These simulations showed that tissue repolarization in such a signal is defined by the steepest upstroke beyond the activation phase (activation was defined by accepted convention as the steepest downstroke). Next, we mapped slow-wave propagation in anesthetized pigs by recording unipolar extracellular potentials from a high-resolution array of electrodes on the serosal surface. Following the simulation result, a wavelet transform technique was applied to detect repolarization in each signal by finding the maximum positive slope beyond activation. Activation-recovery (ARi) and recovery-activation (RAi) intervals were then computed. We hypothesized that these measurements of recovery profile would differ for slow waves recorded during normal and spatially dysrhythmic propagation. We found that the ARi of normal activity was greater than dysrhythmic activity (5.1 ± 0.8 vs. 3.8 ± 0.7 s; P < 0.05), whereas RAi was lower (9.7 ± 1.3 vs. 12.2 ± 2.5 s; P < 0.05). During normal propagation, RAi and ARi were linearly related with negative unit slope indicating entrainment of the entire mapped region. This relationship was weakened during dysrhythmia (slope: −0.96 ± 0.2 vs −0.71 ± 0.3; P < 0.05). NEW & NOTEWORTHY The theoretical basis of the extracellular gastric slow-wave recovery phase was defined using mathematical modeling. A novel technique utilizing the wavelet transform was developed and validated to detect the extracellular slow-wave recovery phase. In dysrhythmic wavefronts, the activation-to-recovery interval (ARi) was shorter and recovery-to-activation interval (RAi) was longer compared with normal wavefronts. During normal activation, RAi vs. ARi had a slope of −1, whereas the weakening of the slope indicated a dysrhythmic propagation.

scholarly journals High-resolution electrical mapping of porcine gastric slow-wave propagation from the mucosal surface

2016 ◽  
Vol 29 (5) ◽  
pp. e13010 ◽  
Author(s):  
T. R. Angeli ◽  
P. Du ◽  
N. Paskaranandavadivel ◽  
S. Sathar ◽  
A. Hall ◽  
...  
Keyword(s):  
Wave Propagation ◽  
High Resolution ◽  
Slow Wave ◽  
Mucosal Surface ◽  
Gastric Slow Wave ◽  
Electrical Mapping

scholarly journals Abnormal gastric slow waves in patients with functional dyspepsia assessed by multichannel electrogastrography

2001 ◽  
Vol 280 (6) ◽  
pp. G1370-G1375 ◽  
Author(s):  
Xuemei Lin ◽  
Jiande Z. Chen
Keyword(s):  
Wave Propagation ◽  
Functional Dyspepsia ◽  
Slow Wave ◽  
Single Channel ◽  
Slow Waves ◽  
Lower Percentage ◽  
Healthy Controls ◽  
Fasting State ◽  
Gastric Slow Wave ◽  
Gastric Slow Waves

The aim of this study was to utilize multichannel electrogastrography to investigate whether patients with functional dyspepsia had impaired propagation or coordination of gastric slow waves in the fasting state compared with healthy controls. The study was performed in 10 patients with functional dyspepsia and 11 healthy subjects. Gastric myoelectrical activity was measured by using surface electrogastrography with a specially designed four-channel device. The study was performed for 30 min or more in the fasting state. Special computer programs were developed for the computation of the propagation and coupling of the gastric slow wave. It was found that, compared with the healthy controls, the patients showed a significantly lower percentage of slow wave propagation (58.0 ± 8.9 vs. 89.9 ± 2.6%, P < 0.002) and a significantly lower percentage of slow wave coupling (46.9 ± 4.4 vs. 61.5 ± 6.9%, P < 0.04). In addition, the patients showed inconsistencies in the frequency and regularity of the gastric slow wave among the four-channel electrogastrograms (EGGs). It was concluded that patients with functional dyspepsia have impaired slow wave propagation and coupling. Multichannel EGG has more information than single-channel EGG for the detection of gastric myoelectrical abnormalities.

scholarly journals High-resolution Mapping of Hyperglycemia-induced Gastric Slow Wave Dysrhythmias

2019 ◽  
Vol 25 (2) ◽  
pp. 276-285 ◽  
Author(s):  
Peng Du ◽  
Gregory O' ◽  
Grady ◽  
Niranchan Paskaranandavadivel ◽  
Shou-jiang Tang ◽  
...  
Keyword(s):  
High Resolution ◽  
Slow Wave ◽  
Gastric Slow Wave ◽  
High Resolution Mapping ◽  
Resolution Mapping

Mo1588 High-Resolution Mapping of Slow Wave Propagation From the Gastric Mucosa Using Flexible Printed Circuit Electrodes

2016 ◽  
Vol 150 (4) ◽  
pp. S721
Author(s):  
Timothy R. Angeli ◽  
Niranchan Paskaranandavadivel ◽  
Peng Du ◽  
Samuel J. Asirvatham ◽  
Gianrico Farrugia ◽  
...  
Keyword(s):  
Wave Propagation ◽  
High Resolution ◽  
Gastric Mucosa ◽  
Slow Wave ◽  
Printed Circuit ◽  
High Resolution Mapping ◽  
Flexible Printed Circuit ◽  
Resolution Mapping

Spatio-temporal characteristic of gastric slow wave propagation in dogs

2000 ◽  
Vol 118 (4) ◽  
pp. A851
Author(s):  
Zhishun Wang ◽  
Hui Ouyang ◽  
Jiande Chen
Keyword(s):  
Wave Propagation ◽  
Slow Wave ◽  
Temporal Characteristic ◽  
Gastric Slow Wave ◽  
Spatio Temporal

scholarly journals Functional physiology of the human terminal antrum defined by high-resolution electrical mapping and computational modeling

2016 ◽  
Vol 311 (5) ◽  
pp. G895-G902 ◽  
Author(s):  
Rachel Berry ◽  
Taimei Miyagawa ◽  
Niranchan Paskaranandavadivel ◽  
Peng Du ◽  
Timothy R. Angeli ◽  
...  
Keyword(s):  
High Resolution ◽  
Computational Modeling ◽  
Slow Wave ◽  
High Amplitude ◽  
Cfd Modeling ◽  
Maximal Velocity ◽  
Anatomical Landmarks ◽  
Electrode Arrays ◽  
Gastric Slow Wave ◽  
Resultant Data

High-resolution (HR) mapping has been used to study gastric slow-wave 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.

scholarly journals Automated Gastric Slow Wave Cycle Partitioning and Visualization for High-resolution Activation Time Maps

2010 ◽  
Vol 39 (1) ◽  
pp. 469-483 ◽  
Author(s):  
Jonathan C. Erickson ◽  
Greg O’Grady ◽  
Peng Du ◽  
John U. Egbuji ◽  
Andrew J. Pullan ◽  
...  
Keyword(s):  
High Resolution ◽  
Slow Wave ◽  
Activation Time ◽  
Gastric Slow Wave ◽  
Wave Cycle
Sign in / Sign up

Export Citation Format

Share Document