HIATAL-HERNIA SIZE AFFECTS LOWER ESOPHAGEAL SPHINCTER FUNCTION, ESOPHAGEAL ACID EXPOSURE, AND THE DEGREE OF MUCOSAL INJURY

BACKGROUND: Since the role of a hiatal hernia in the pathophysiology o f gastroesophageal reflux disease (GERD) has not been fully elucidated , we studied the effects of hiatal hernias on the function of the lowe r esophageal sphincter (LES) and esophageal acid clearance. PATIENTS A ND METHODS: Ninety-five consecutive patients with GERD diagnosed by 24 -hour pH monitoring underwent upper gastrointestinal series (UGI), end oscopy, and esophageal manometry. Based on the presence (H+) or absenc e (H-) of a hiatal hernia on UGI series, they were divided into two gr oups: H+ (n = 51) and H- (n = 44), Then, using the size of the hiatal hernia, the H+ group was divided into three subgroups: I, H <3 cm (n = 31); II, H 3.0 to 5 cm (n = 14); and III, H >5 cm (n = 6). RESULTS: E sophageal manometry showed that patients with larger hiatal hernias (g roups II and III) had a weaker and shorter LES and less effective peri stalsis compared to patients with a small or no hiatal hernia. Prolong ed pH monitoring showed that patients with larger hiatal hernias were exposed to more refluxed acid and had more severely abnormal acid clea rance. Endoscopy showed more severe esophagitis among patients with GE RD and hiatal hernia compared with GERD patients without hiatal hernia , and the degree of esophagitis was proportionate to the size of the h ernia. CONCLUSIONS: Among patients with proven GERD, those with a smal l hiatal hernia and those with no hiatal hernia had similar abnormalit ies of LES function and acid clearance. In patients with larger hiatal hernias, however, the LES was shorter and weaker, the amount of reflu x was greater, and acid clearance was less efficient. Consequently, th e degree of esophagitis was worse in the presence of a large hiatal he rnia.