Article

A unique longitudinal muscle contraction pattern associated with transient lower esophageal sphincter relaxation.

Division of Gastroenterology, San Diego VA Health Care System and University of California, San Diego, California.
Gastroenterology (impact factor: 11.68). 06/2008; 134(5):1322-31. DOI:10.1053/j.gastro.2008.02.031 pp.1322-31
Source: PubMed

ABSTRACT Contraction of the longitudinal muscle of the esophagus may play a role in the relaxation and opening of the lower esophageal sphincter (LES). The goal of our study was to determine the pattern and precise temporal correlation between local longitudinal muscle contraction (LMC) of the esophagus during peristalsis and transient LES relaxation (TLESR).
Esophageal pressures and high-frequency intraluminal ultrasound imaging of the esophagus were recorded in 24 healthy subjects during swallow-induced peristalsis and spontaneous TLESR. Intraluminal multiple impedance recordings were obtained to determine the relationship between "common cavity pressure" and gastroesophageal reflux (GER).
During swallow-induced peristalsis, there is simultaneous contraction of circular and longitudinal muscles of the esophagus. On the other hand, TLESR is associated with a distinct pattern of LMC in the esophagus that has the following characteristics: (1) it is restricted to the distal esophagus; (2) it begins before the onset of TLESR and spreads in a retrograde manner; (3) it is generally stronger than the swallow-induced contraction; and (4) it is sustained during the entire duration of TLESR. The increase in esophageal pressure during TLESR is temporally correlated with the contraction of the LM of the distal esophagus, rather than with the impedance recorded GER.
We propose that the LMC of the distal esophagus may play an important role in the relaxation of LES and induction of GER.

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Keywords

24 healthy subjects
 
common cavity pressure
 
distal esophagus
 
entire duration
 
esophageal pressure
 
Esophageal pressures
 
following characteristics
 
gastroesophageal reflux
 
high-frequency intraluminal ultrasound imaging
 
Intraluminal multiple impedance recordings
 
local longitudinal muscle contraction
 
longitudinal muscle
 
longitudinal muscles
 
lower esophageal sphincter
 
precise temporal correlation
 
retrograde manner
 
spontaneous TLESR
 
swallow-induced contraction
 
swallow-induced peristalsis
 
transient LES relaxation