Background: Because of the wide overlap between the groups, patients with reflux esophagitis (RE) cannot be distinguished from healthy subjects by basal lower esophageal sphincter (LES) pressure. The LES has radial asymmetry, with maximum pressure on the left side. It has been noted that one directional LES pressure, determined using the rapid pull-through (RPT) method, in most patients with severe RE is very low, compared with that in healthy subjects. The aim of this study was to examine whether or not the minimum value of four directional LES pressures could become an index of RE by the RPT method.
Methods: Thirty patients with severe RE (grade C or D of the Los Angeles classification) were compared with 30 patients with mild RE (grade A or B) and 30 healthy subjects of comparable age and sex. LES pressure was measured by the RPT method, with the subject in the supine position. The catheter was withdrawn manually at a rate of 10 mm/s during suspended respiration at the end-expiratory phase after 5-min rest accommodation. LES pressure, with reference to the intragastric fundic pressure, was recorded by three consecutive RPTs, and 12 LES pressures were obtained for each subject.
Results: Minimum LES pressure, mean LES pressure, and maximum LES pressure were calculated from the 12 LES pressures. Wide overlaps in the mean and maximum LES pressures between healthy subjects and patients with mild or severe RE occurred; however, the overlap of minimum LES pressure between these groups was clearly less than that for the mean and maximum LES pressures. If it is accepted that more than the tenth percentile of the minimum LES pressure in healthy subjects is the cutoff value for healthy subjects, the sensitivity was 93.3% and the specificity for severe RE was 93.3%.
Conclusions: This finding would suggest that the minimum LES pressure determined by the RPT method is an index of severe RE.