Diagnosis of Ineffective Esophageal Motility According to Chicago Classification Version 4.0: More Stringent Criteria, but Also New Difficulties.

c 2023 The Korean Society of Neurogastroenterology and Motility J Neurogastroenterol Motil, Vol. 29 No. 2 April, 2023 www.jnmjournal.org TO THE EDITOR: We read with great interest the study by Kurin et al about the clinical characteristics of patients with ineffective esophageal motility (IEM) comparing diagnosis according to the Chicago classification version 3.0 (CC v3.0) versus CC v4.0. Kurin et al demonstrated that 41 patients out of the 66 patients selected with IEM at high-resolution manometry (HRM) according to CC v3.0 also met the criteria for IEM according to the new CC v4.0. This subgroup of 41 patients had higher acid exposure time (especially in the supine position), lower adequate peristaltic reserve and higher Demeester score. We agree that CC v4.0, with its more stringent criteria, allows a clearer diagnosis of IEM. However, in our clinical practice, changes in the examination protocol have been brought to light critical issues. Specifically, the new HRM protocol according to CCv 4.0 includes 10 swallows in the supine or upright position followed by 5 swallows in the opposite position. We applied the new protocol to all new HRMs. In 15 patients who complained of dysphagia or were undergoing a pre-bariatric surgery evaluation we obtained a diagnosis of IEM in the supine or upright position but not in the opposite position. Compared with diagnosis of esophagogastric junction outflow obstruction or absent contractility in which CC v4.0 specifies the importance of pathological alterations in both positions, this aspect was not described in IEM diagnosis. Consequently, there is some concern in managing such an ambiguous situation. Our group evaluated the use of additional tests to support the diagnosis of IEM such as multiple rapid swallows’ or rapid drink challenge performed in both positions. Even in these contexts, we found mixed results related to the 2 positions. Another possible auxiliary test described is the use of solid swallowing, although scientific evidence to support this test is still lacking. In these complex situations, we provided an “inconclusive” diagnosis of IEM and recommended a 24-hour pH-impedance testing to assess for the presence of gastroesophageal reflux disease and a further manometric assessment after at least 1 year. We hope CC v5.0 will provide more clarity on this topic and allow us to obtain certainty in the diagnosis of IEM according to the new protocol for performing HRM.