A new mechanism of gastroesophageal reflux in hiatal hernia documented by high-resolution impedance manometry: a case report

Gastroesophageal reflux disease (GERD) is recognized to be a multifactorial disease and several mechanisms leading to reflux have been described, nevertheless its pathophysiology has not been fully clarified. Hiatus hernia is a known risk factor for GERD since it impairs the esophagogastric junction, leading to: reduction in lower esophageal sphincter pressure; increase in the frequency of the transient lower esophageal sphincter relaxation; and impairment of esophageal clearance. Last generation diagnostic techniques have improved the understanding of these mechanisms. A 72-year-old woman with hiatus hernia and GERD underwent a high resolution impedance manometry (HRIM) after a partial response to treatment with pantoprazole. None of the proposed pathophysiological mechanisms for GERD could explain the presence of reflux: HRIM showed normal lower esophageal sphincter (LES) pressure and contractile integral, complete bolus clearance in all test swallows, and absence of transient LES relaxation. However, after the end of each peristaltic wave, as the LES pressure returned to resting values, a gastroesophageal reflux was detected until the following swallow. We describe an interesting case of a patient with a sliding hiatus hernia, with symptoms suggestive of GERD, in which HRIM revealed a new possible mechanism through which hiatus hernia may lead to GERD.