Correlation of the Endoscopic Gastroesophageal Flap Valve with Pathologic Reflux

The Hill classification characterizes the geometry of gastroesophageal junction and Hill grades (HGs) III and IV have a high association with pathologic reflux. This study aimed to understand the use of the Hill classification and correlate the prevalence of pathologic reflux across different HGs.

A retrospective review of 477 patients who underwent upper endoscopy and BRAVO pH monitoring between August 2018 and October 2021 was performed. These charts were reviewed for endoscopic findings for hiatal hernia and association of HGs with pathologic reflux, defined as an abnormal esophageal acid exposure time (AET) of ≥4.9%.

Of 477 patients, 252 (52.8%) had an HG documented on the endoscopy report. Of the 252 patients, 61 had HG I (24.2%), 100 had HG II (39.7%), 61 had HG III (24.2%), and 30 had HG IV (11.9%). The proportion of patients with abnormal AET increases with increasing HGs (p < 0.001) as follows: I (39.3%), II (52.5%), III (67.2%), and IV (79.3%). The mean overall AET is as follows: HG I (5.5 ± 6%), HG II (7.0 ± 5.9%), HG III (10.2 ± 10.3%), and HG IV (9.5 ± 5.5%). The proportion of patients with hiatal hernia was 18% for HG I, 28% for HG II, 39.3% for HG III, and 80% for HG IV.

Use of the Hill classification in clinical practice is low. There is an association of increasing HGs with increasing proportion of patients with abnormal AET. There is a high proportion of patients within HGs I and II with documented pathologic reflux and the presence of a hiatal hernia as observed on endoscopic examination. Our study suggests that endoscopic grading of the gastroesophageal junction may not adequately differentiate between normal vs abnormal reflux status, particularly for HGs I and II.