Increased frequency of transient lower esophageal sphincter relaxation induced by gastric distention in reflux patients with hiatal hernia.

BACKGROUND & AIMS: This study aimed to determine if hiatal hernia influences vulnerability to reflux and transient lower esophageal sphincter relaxation (tLESR) during gastric distention in patients with gastroesophageal reflux disease (GERD).
METHODS: Eight normal subjects and 15 patients with GERD were studied. A metal clip attached to the squamocolumnar junction (SCJ) was beneath the hiatus in all control subjects. Eight GERD patients with >/=1-cm SCJ-hiatus separation were considered hernia patients, and 7 with <1-cm separation were considered nonhernia patients. Manometry and esophageal pH were recorded for 30 minutes, after which the stomach was loaded with acid dextrose and the recording continued for 2 hours with intragastric air infusion of 15 mL/min.
RESULTS: Baseline reflux was comparable among groups. Gastric distention increased the frequency of reflux by the tLESR mechanism in all groups. Controls and nonhernia patients had median increases of 4.0 and 4.5 in tLESR frequency, respectively, and hernia patients had a median increase of 9.5/h. tLESR frequency was highly correlated with the SCJ-hiatus separation (r = 0.76; P < 0.001).
CONCLUSIONS: Gastric air infusion was a potent stimulus for tLESR and reflux. The resultant tLESR frequency was directly proportional to the separation between the SCJ and hiatus, suggesting that the perturbed anatomy associated with hiatal hernia predisposed to eliciting tLESRs in patients with GERD.