Intermittent spatial separation of diaphragm and lower esophageal sphincter favors acidic and weakly acidic reflux

Gastroenterology. 2006 Feb;130(2):334-40. doi: 10.1053/j.gastro.2005.10.053.


Background & aims: In small hiatal hernias, the size of the hernia is variable. Intermittent complete reduction can be observed with high-resolution manometry as a transition from a double-peak (hernia) to a single-peak (reduced) high-pressure zone. The aim of this study was to investigate whether intermittent separation of the diaphragm and lower esophageal sphincter (LES) favors the occurrence of gastroesophageal reflux.

Methods: In 16 patients with a small hiatal hernia (3 cm), prolonged high-resolution manometry was performed. Acid and weakly acidic reflux episodes were detected with pH-impedance monitoring.

Results: The single pressure peak profile (reduced hernia) was present for 814 minutes (56.5% of total time), and the double peak profile (unreduced hernia) was present for 626 minutes (43.5% of total time). In all patients, both pressure profiles were observed. The transition rate between the 2 profiles was 7.5 +/- 0.9 per hour. More reflux occurred when the LES and diaphragm were separated versus the reduced hernia state (23.1 +/- 5.1 vs 12.2 +/- 2.4 episodes per hour, respectively; P < .05). The proportions of acidic reflux episodes during the single and double pressure peaks were similar (70% and 67%, respectively). In the two-pressure-zone state, there was an increase in all reflux mechanisms except transient LES relaxation.

Conclusions: In patients with a small hiatal hernia, intermittent reduction of the hernia occurs frequently. Spatial separation of the diaphragm and LES in the nonreduced state results in a 2-fold increase in acidic and weakly acidic reflux due to mechanisms other than transient LES relaxation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Diaphragm / anatomy & histology*
  • Diaphragm / diagnostic imaging
  • Esophagus / anatomy & histology*
  • Esophagus / diagnostic imaging
  • Gastric Acid / metabolism
  • Gastroesophageal Reflux / classification
  • Gastroesophageal Reflux / diagnostic imaging
  • Gastroesophageal Reflux / etiology
  • Gastroesophageal Reflux / physiopathology*
  • Hernia, Hiatal / complications
  • Humans
  • Hydrogen-Ion Concentration
  • Jejunum / anatomy & histology
  • Pressure
  • Radiography
  • Reproducibility of Results