Ineffective esophageal motility: The impact of change of criteria in Chicago Classification version 4.0 on predicting outcome after magnetic sphincter augmentation

Background: The most recent update of the Chicago Classification (CCv4.0) attempts to provide a more clinically relevant definition for ineffective esophageal motility (IEM). The impact of this new definition on predicting outcome after antireflux surgery is unknown. The aim of this study was to compare utility of IEM diagnosis based on CCv4.0 to CCv3.0 in predicting surgical outcome after magnetic sphincter augmentation (MSA) and to assess any additional parameters that hold value in future definitions.

Methods: Records of 336 patients who underwent MSA at our institution between 2013 and 2020 were reviewed. Preoperative manometry files were re-analyzed using both Chicago Classification version 3.0 (CCv3.0) and CCv4.0 definitions of IEM. The utility of each IEM definition in predicting surgical outcome was then compared. Individual manometric components and impedance data were also assessed.

Key results: Immediate dysphagia was reported by 186 (55.4%) and persistent dysphagia by 42 (12.5%) patients. CCv3.0 IEM criteria were met by 37 (11%) and CCv4.0 IEM by 18 (5.4%) patients (p = 0.011). CCv3.0 and CCv4.0 IEM were equally poor predictors of immediate (AUC = 0.503 vs. 0.512, p = 0.7482) and persistent (AUC = 0.519 vs. 0.510, p = 0.7544) dysphagia. The predicted dysphagia probability of less than 70% bolus clearance (BC) was 17.4%, higher than CCv4.0 IEM at 16.7%. When BC was incorporated into CCv4.0 IEM criteria, the probability increased significantly to 30.0% (p = 0.0042).

Conclusions & inferences: The CCv3.0 and CCv4.0 of IEM are poor predictors of dysphagia after MSA. Adding BC to the new definition improves its predictive utility and should be considered in future definitions.