Manometric Study of Hiatal Hernia and Its Correlation with Esophageal Peristalsis

The pathogenesis of gastroesophageal refluxdisease (GERD) is considered multifactorial, butalterations of the esophagogastric junction (EGJ) andhiatal hernia play a prominent role. The correlationsbetween hiatal hernia and the other pathogeneticfactors are as yet unclear, and they need to beinvestigated by a methodological approach based on newanatomic and functional criteria. Our aim was to study,by stationary manometry, the relationships betweensmall reducible hiatal hernia, identified by endoscopy,and esophageal peristalsis, in patients with and withoutGERD. According to the absence or presence of esophagitis (E), and the absence or presenceof hiatal hernia (H), 58 subjects were divided into fourgroups: controls 10; H 14; E 10; and HE 24. Stationarymanometry was performed by the rapid pull-through (RPT) technique, with catheter water perfused,to study the lower esophageal high pressure zone loweresophageal sphincter (LES) and diaphragmatic crura] andthe parameters of esophageal peristalsis. In patients with hiatal hernia, the variouscombinations of peak and/or deflection of manometricline pressure identified five EGJ profiles, only one ofwhich reveals (by one-peak profile due to superimposed LES and diaphragmatic crura) the reducibilityof the hernia. The frequency of the five profiles wascalculated in the HE and H groups: a two-peak profilewas significantly more prevalent in these patients, although less so in the group with esophagitis.In E patients the distal amplitude and the distalpropagation of esophageal waves were significantly lowerthan in the other three groups (P < 0.05 vs controls and group HE; P < 0.01 vs group H).Furthermore, the distal amplitude was significantlyhigher in the group H than in the HE (P < 0.01). Ourresults show a better definition of hiatal hernia morphology, via the RPT technique, disclosingfive pressure profiles. In addition, a significant linkwas found between small reducible hiatal hernia withoutGERD and wave amplitude of the distal esophagus. The amplification of peristaltic clearing maybe considered the initial protective process againstacid reflux; the breakdown of this mechanism may triggerthe pathological sequence of GERD.