Criteria for objective definition of transient lower esophageal sphincter relaxation

TLDR

The authors developed and evaluated objective manometric criteria to define transient lower esophageal sphincter relaxation. They performed systematic esophageal manometry and pH monitoring in 23 normal subjects and 9 GERD patients, showing that dry swallows precede LES relaxation by a median of 1.4 s and classifying 104 reflux‑associated LES pressure falls as transient relaxations or not. Transient LES relaxation was defined by a relaxation rate >1 mmHg/s, a nadir pressure ≤2 mmHg, a duration ≤10 s, and the absence of swallowing within 4 s before to 2 s after onset, with 90 % of visually identified events meeting these criteria. The abstract is truncated at 250 words.

Abstract

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. 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. 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)