Endoscopic Classification of Fundoplication Integrity Predicts Pathologic Reflux

Overview

This single-center, two-phase cohort study aimed to develop and validate a simple endoscopic classification of fundoplication integrity after anti-reflux surgery (ARS - Nissen or Toupet fundoplication). Consecutive adult patients undergoing endoscopy, high-resolution manometry (HRM), and reflux monitoring after ARS were included. Retroflexed endoscopic videoclips were reviewed blinded to clinical and functional results. In the development cohort (2018-2024, n=73), individual endoscopic parameters were tested against pathologic GERD (Lyon 2.0 criteria). Three parameters significantly correlated with pathologic reflux: (1) intrathoracic valve location, (2) disrupted valve (deep anterior and/or posterior grooves), and (3) visible hiatal opening. Patients were stratified according to the number of impaired mechanisms (0-3). Symptom burden, manometric abnormalities, and reflux metrics worsened progressively with increasing impairment. The rate of pathologic GERD rose from 11.8% (0 mechanisms) to 37.5% (1-2 mechanisms) to 85.7% (3 mechanisms). The classification was then prospectively validated in an independent cohort (2024-2026, n=49), reproducing the same stepwise correlation. The number of impaired mechanisms showed excellent discriminatory capacity for pathologic GERD (AUC 0.860 in development, 0.870 in validation; overall AUC 0.869). This simple endoscopic classification, based on only three objective parameters, reliably identifies fundoplication failure and correlates with symptoms and objective pathophysiologic data. It has the potential to standardize endoscopic reporting after ARS.

This is a single-center observational cohort study designed to develop and prospectively validate a simple endoscopic classification of the fundoplication after anti-reflux surgery (ARS), using clinical symptoms and objective functional testing as the reference. Consecutive adult patients undergoing follow-up esophagogastroduodenoscopy (EGD), high-resolution manometry (HRM) and ambulatory reflux monitoring after Nissen or Toupet fundoplication are studied. The protocol is carried out in two phases. In the development phase, retroflexed endoscopic videoclips are collected and de-identified by one investigator and independently reviewed by a senior foregut surgeon and endoscopist, blinded to the results of HRM and reflux monitoring. For each patient, the reconstructed gastro-esophageal valve is characterized by five parameters: valve location (intra-abdominal versus intrathoracic), degree of disruption (graded on the depth of the anterior and posterior grooves), visibility of the hiatal opening, valve lip thickness, and the presence of a para-esophageal hernia. HRM is performed according to the Chicago Classification v4.0, including provocative maneuvers (multiple rapid swallows and straight leg raise), and interpreted using the Padova Consensus criteria for post-fundoplication manometry. Reflux monitoring is performed off acid-suppressive therapy using 24-hour pH-impedance or wireless pH monitoring, and interpreted according to the Lyon 2.0 criteria. The endoscopic parameters found to be associated with pathologic reflux are combined into an ordinal score based on the number of impaired mechanisms (0 to 3), and its discriminative performance is quantified by the area under the ROC curve. In the second phase, the classification is applied to an independent, prospectively enrolled cohort assessed under the same protocol, and its performance is compared with that of the development phase. The study is reported in accordance with the TRIPOD statement.