Fragmented and failed swallows on esophageal high-resolution manometry associate with abnormal reflux burden better than weak swallows

Abstract

Background: Association between proportions of hypomotile swallows on esophageal high-resolution manometry (HRM) and esophageal reflux burden remains incompletely understood. We investigated relationships between hypomotility, acid exposure time (AET), and mean nocturnal baseline impedance (MNBI) on ambulatory reflux monitoring. Methods: Clinical data, HRM, and ambulatory pH-impedance studies (performed off acid suppression) from patients with persisting reflux symptoms were reviewed from five international centers. AET (abnormal > 6%) and MNBI (abnormal < 2292 ohms) were extracted from pH-impedance studies. Distal contractile integral (DCI) designated esophageal peristalsis into normal (DCI > 450 mmHg.cm.s), fragmented (DCI > 450 mmHg.cm.s with breaks > 5 cm), weak (DCI 100-450 mmHg.cm.s), and failed (DCI < 100 mm mmHg.cm.s) sequences. Univariate and multivariate analyses were performed to identify motor associations of abnormal reflux burden. Key Results: Of 351 patients (52.1 ± 0.8 years, 67%F), 29.3% had AET > 6% and 61.8% had MNBI < 2292 ohms. On univariate analysis, both fragmented peristalsis and IEM associated with abnormal AET (P ≤.01) and MNBI (P ≤.03); reflux burden was more profound with >70% fragmented as well as ineffective sequences compared to ≤70% for each (P 70% ineffective sequences trended strongly (P =.069); >70% ineffective sequences predicted abnormal MNBI (P =.046), and >70% fragmented sequences trended strongly (P =.076). Conclusions and Inferences: Breaks in esophageal peristaltic integrity seen with fragmented and failed sequences are more relevant to abnormal esophageal acid burden than weak sequences.