Do Large Hiatal Hernias Affect Esophageal Peristalsis?

Abstract

Background: Large hiatal hernias (LHH) can be associated with esophageal shortening and/ or a tortuous esophagus. We hypothesized that these anatomic changes may induce motility changes that would systematically alter high resolution esophageal pressure topography (EPT) measurements. Aim: To compare EPT measures of esophageal motility in patients with LHH to those of matched patients without hernia. Methods: Among 2000 consecutive clinical EPT, we identified 49 patients with LHH on endoscopy (hernia >5 cm) and with at least 7 evaluable swallows on EPT. Within the same database (after exclusion of patients with achalasia, absent peristalsis, or previous gastrointestinal surgery) a control group without hernia on endoscopy was selected, matched for gender, age, and symptoms (dysphagia, reflux). EPT were subsequently analyzed for: lower esophageal sphincter (LES) or esophagogastric junction (EGJ) pressure, intragastric pressure, Integrated Relaxation Pressure (IRP), Distal Contractile Integral (DCI), Contractile Front Velocity (CFV) and Distal Latency time (DL) between the onset of contraction at the upper esophageal sphincter (UES) and the contractile deceleration point. Esophageal length was measured on EPT from the distal border of UES to the proximal border of LES at 20-mmHg isobaric contour. EGJ morphology was also characterized, and an EPT diagnosis (Chicago Classification) was made for each patient based on individual swallow characteristics. EPT characteristics were summarized as median (IQR).The two groups were then compared using the chi-squared test for categorical data and the Mann Whitney test for continuous data. Results: Patients with LHH had a significant shorter esophagus than patients without hernia (21 (18.9-23.3) cm vs 25.4 (24.2-27.2), p<0.01). In patients with LHH, EPT studies were classified as normal (n=21), weak peristalsis (n=18), frequent failed peristalsis (n=4), spasm (n=1), rapid contractions with normal latency (n=3), hypertensive peristalsis (n=1) and functional obstruction (n=1). The distribution of motility disorder diagnoses was not different in patients with LHH and in the matched patients without hernia (p = 0.82). Significant differences were seen in EGJ pressures, IRP, intragastric pressure, DCI and DL between groups (Table). However the correlation between the esophageal length and the mean DCI was weak (r=0.23, p=0.02) as well as the correlation between the esophageal length and the DL (r=0.24, p=0.02). Conclusions: In addition to a lower pressure at the EGJ, patients with LHH also had significantly lower DCI and shorter DL on EPT as a consequence of the associated shortened esophagus. However, despite these differences in individual parameters, the final diagnosis and distribution of motility disorders was unaffected by the presence of a hernia.