Criteria for objective definition of transient lower esophageal sphincter relaxation

Am J Physiol. 1995 Jan;268(1 Pt 1):G128-33. doi: 10.1152/ajpgi.1995.268.1.G128.


We developed and evaluated objective manometric criteria that define transient lower esophageal sphincter (LES) relaxation. In 23 normal subjects and 9 patients with gastroesophageal reflux disease, systematic analysis of swallow-induced LES relaxation showed that dry swallows preceded LES relaxation by a median of 1.4 s. The relaxation rate was always > 1 mmHg/s, the relaxation nadir always occurred within 7 s, and the duration of relaxation was < 9 s. During concurrent esophageal manometry and pH monitoring, 104 reflux episodes associated with a LES pressure fall that was not related to swallowing were identified and the pressure falls classified as transient LES relaxations or not by visual recognition. LES pressure was always < or = 2 mmHg at time of reflux, and relaxation was significantly longer than for swallow-induced LES relaxation. Of 88 pressure falls classified visually as transient LES relaxations, 90% reached nadir pressure within 7 s at a rate of > 1 mmHg/s. Sixteen pressure falls were classified as a gradual downward drift in LES pressure, which in 15 cases was < 1 mmHg/s. Based on the analysis, transient LES relaxation can be defined by 1) absence of swallowing for 4 s before to 2 s after the onset of LES relaxation, 2) relaxation rate of > or = 1 mmHg/s, 3) time from onset to complete relaxation of < or = 10 s, and 4) nadir pressure of < or = 2 mmHg.(ABSTRACT TRUNCATED AT 250 WORDS)

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Deglutition / physiology
  • Esophagogastric Junction / physiology*
  • Female
  • Gastroesophageal Reflux / physiopathology
  • Humans
  • Male
  • Middle Aged
  • Muscle Relaxation*
  • Pressure
  • Terminology as Topic
  • Time Factors