Esophagogastric junction opening during relaxation distinguishes nonhernia reflux patients, hernia patients, and normal subjects

BACKGROUND AND AIMS: Flow across the esophagogastric junction (EGJ) is strongly related to opening dimensions. This study aimed to determine whether opening of the relaxed EGJ was altered in patients with gastroesophageal reflux disease (GERD). METHODS: Seven normal subjects (NL), 9 GERD patients without hiatus hernia (NHH), and 7 with hiatus hernia (HH) were studied. Cross-sectional area (CSA) of the relaxed EGJ was measured during low-pressure distention using a modified barostat technique that resulted in filling a compliant bag straddling the EGJ with renograffin to the set pressure. Swallows were imaged fluoroscopically at distensive pressures of 2-12 mm Hg. The diameter of the narrowest point of the EGJ in PA and lateral projections was measured from digitized images. CSA was determined as a function of intrabag pressure. RESULTS: The minimal EGJ opening aperture occurred at the diaphragmatic hiatus in all subjects. At pressures 0 mm Hg, there were significant increases in EGJ CSA both for HH and NHH compared with NL (P < 0.001) and for HH compared with NHH (P < 0.005). This difference may explain the diminished air/water discrimination seen during transient lower esophageal sphincter (LES) relaxation-associated reflux in GERD patients. CONCLUSIONS: Anatomic degradation of the EGJ distinguishes GERD patients from normal subjects, and these changes may impact on both the observed mechanisms of reflux and the constituents of reflux during transient LES relaxation. Therapy focused on EGJ compliance may benefit GERD patients.     

The role of transsphincteric pressure and proximal gastric volume in acid reflux before and after fundoplication

BACKGROUND & AIMS: This study was conducted to explore the role of proximal gastric volume and transsphincteric pressure on acid reflux during transient lower esophageal sphincter relaxation (TLESR) in patients with gastroesophageal reflux disease (GERD) both before and after laparoscopic fundoplication. METHODS: Twenty GERD patients were studied before and after fundoplication along with 20 healthy controls. High-resolution manometry and pH recording was performed for 1 hour before and 2 hours following meal ingestion (500 mL/300 kcal). Three-dimensional ultrasonographic images of the stomach were acquired before and every 15 minutes after meal ingestion. RESULTS: Postprandial proximal to total gastric volume distribution ratios were significantly larger in GERD patients before fundoplication (0.57 +/- 0.01; P < .05) and smaller following fundoplication (0.37 +/- 0.01; P < .001) compared with controls (0.46 +/- 0.01). The percentage of TLESRs associated with acid reflux did not relate to proximal gastric volume in any subject group. The transsphincteric pressure profile was different for TLESRs with and without reflux in GERD patients as well as in healthy controls. The pressure gradient across the esophagogastric junction (EGJ) (DeltaEGJp) was greater for TLESRs with acid reflux compared with TLESRs without acid reflux in both GERD patients (11.4 +/- 0.8 vs 8.0 +/- 0.5 mm Hg, respectively; P < .01) and controls (10.6 +/- 0.7 vs 7.1 +/- 0.8 mm Hg, respectively; P < .05). After fundoplication, DeltaEGJp during TLESRs was 7.9 +/- 0.9 mm Hg, and the transsphincteric pressure profile markedly changed. CONCLUSIONS: Although proximal gastric volume plays a key role in eliciting TLESRs, it is not related to the incidence of acid reflux during TLESRs. The transsphincteric pressure gradient is greater in TLESRs associated with acid gastroesophageal reflux.