The effect of hiatus hernia on gastro-oesophageal junction pressure

Abstract

Background-Hiatus hernia and lower oesophageal sphincter hypotension are often viewed as opposing hypotheses for gastro-oesophageal junction incompetence. Aims-To examine the interaction between hiatus hernia and lower oesophageal sphincter hypotension. Methods-In seven normal subjects and seven patients with hiatus hernia, the squamocolumnar junction and intragastric margin of the gastro-oesophageal junction were marked with endoscopically placed clips. Axial and radial characteristics of the gastro-oesophageal junction high pressure zone were mapped relative to the hiatus and clips during concurrent fluoroscopy and manometry. Responses to inspiration and abdominal compression were also analysed. Results-In normal individuals the squamocolumnar junction was 0.5 cm below the hiatus and the gastro-oesophageal junction high pressure zone extended 1.1 cm distal to that. In those with hiatus hernia, the gastro-oesophageal junction high pressure zone had two discrete segments, one proximal to the squamocolumnar junction and one distal, attributable to the extrinsic compression within the hiatal canal. Inspiration and abdominal compression mainly augmented the distal one. Simulation of hernia reduction by algebraically summing the proximal segment pressures with the hiatal canal pressures restored normal maximal pressure, radial asymmetry, and dynamic responses of the gastro-oesophageal junction. Conclusions-Hiatushernia reduces lower oesophageal sphincter pressure and alters its dynamic responsiveness by spatially separating pressure components derived from the intrinsic lower oesophageal sphincter and the extrinsic compression of the oesophagus within the hiatal canal. (Gut 1999;44:476-482)

Different patterns of oesophageal acid exposure distinguish complicated reflux disease from either erosive reflux oesophagitis or non‐erosive reflux disease

“…These findings confirm that peristaltic dysfunction contributes to increased oesophageal exposure to refluxed acid material, 31 particularly in the supine position when it is associated with impaired oesophageal clearance. 34 Moreover, our results confirm that the presence of hiatal hernia contributes much more than the basal lower oesophageal sphincter tone to the presence and severity of endoscopically detectable mucosal lesions in GERD, [35][36][37] and this is in keeping with its relevance in the management of complicated and atypical GERD. 26 The severity of heartburn was similar between the three groups of patients in our series, confirming that NERD should not be considered as a mild form of GERD, 3 and that the severity of reflux symptoms is similar when patients with erosive reflux oesophagitis and with complicated reflux disease are compared.…”

Approaches to the diagnosis and grading of hiatal hernia

“…The phrenoesophageal membrane is formed from the fascia transversalis on the under surface of the diaphragm and, to a lesser degree, fused elements of the endothoracic fascia. This elastic membrane inserts circumferentially into the esophageal musculature, close to the squamocolumnar junction, and extends for about a centimeter above the gastroesophageal junction [5]. Thus, the axial position of the squamocolumnar junction is normally within or slightly distal to the diaphragmatic hiatus and surrounded by the crural diaphragm [6].…”

“…With such studies, the locations and pressure contributions of the LES and crural diaphragm can be localized within the EGJ pressure signature. Figure 8 illustrates two examples of such studies obtained from a normal individual and a subject with a sliding hernia [5]. The pull-throughs were done under fluoroscopy using a motorized puller to calibrate position, a manometric catheter with radio-opaque markings to correlate pressure locus with fluoroscopic landmarks, and endoclips located at the intragastric extreme of the EGJ and at the SCJ.…”

The Acid Pocket: A Target for Treatment in Reflux Disease?

“…Hiatus hernia is intimately involved in the pathogenesis of GERD, impairing both LES function and esophageal clearance, thereby increasing esophageal acid exposure ( 44,45 ). Studies suggest that the presence of hiatus hernia may also infl uence refl ux disease through eff ects on the size and position of the acid pocket.…”