Multiple Rapid Swallow Maneuver Enhances the Clinical Utility of High-Resolution Manometry in Patients Showing Ineffective Esophageal Motility
The clinical significance of ineffective esophageal motility (IEM) together with multiple rapid swallow (MRS) has not been yet evaluated in the Chicago Classification v3.0. This study evaluated the adjunctive role of MRS in IEM and determined the criteria of abnormal MRS to maximize the utility of IEM. We analyzed 186 patients showing IEM or normal esophageal motility (NEM), who underwent esophageal high-resolution impedance-manometry for esophageal symptoms. Two different criteria for abnormal MRS were applied to IEM subjects, resulting in 2 corresponding subgroups: IEM-A when distal contractile integral (DCI) ratio between an average wet swallows and MRS contraction was < 1 and IEM-B when MRS contraction DCI was <450 mm Hg-s-cm. One IEM subject inadequately performed MRS. Among the remaining 52 IEM subjects, 18 (34.6%) were classified into IEM-A and 23 (44.2%) into IEM-B. IEM subjects showed less complete bolus transit (median 0.0%, interquartile range 0.0-20.0% vs 60.0%, 30.0-80.0; P < 0.001) resulting in higher impaired bolus transit than NEM subjects (98.1% vs 66.9%, P = 0.001). IEM-B subjects showed additionally higher pathologic bolus exposure than NEM subjects (55.6% vs 29.3%, P = 0.001), whereas IEM-A subjects could not. Although IEM-B subjects had the highest prevalence of gastroesophageal reflux disease among the subjects groups, it did not reach statistical significance. In conclusion, IEM patients with abnormal MRS contraction have an increased risk of prolonged bolus clearance, poor bolus transit, and pathologic bolus exposure. IEM patients need to be assessed concerning whether MRS contraction DCI is < 450 mm Hg-s-cm to segregate clinically relevant patients.