S948 Multimodal Assessment of Esophageal Peristalsis in Gastroesophageal Reflux Disease

Introduction: Peristalsis is a defense mechanism against gastroesophageal reflux disease (GERD) by clearing refluxate. Data are limited regarding the relative contributions of primary peristalsis, secondary peristalsis, and peristaltic augmentation in GERD. Aim: evaluate the association between these peristaltic metrics and GERD via a multimodal approach. Methods: Retrospectively analyzed patients with esophageal symptoms who underwent functional lumen imaging probe (FLIP) panometry (propofol-sedated, 16 cm balloon), high-resolution manometry (HRM) with multiple rapid swallows (MRS), and reflux monitoring (wireless pH or catheter-based pH-impedance off proton pump inhibitors). GERD was defined as percent time pH < 4 acid exposure time (AET) >6%. Exclusion criteria included achalasia, prior foregut surgery, botulinum toxin injection within 6 months, and indeterminate AET (4-6%). Secondary peristalsis was intact if repetitive antegrade contractions were seen on FLIP; esophagogastric junction (EGJ) distensibility index (DI) at 60 mL and max diameter at 60-70 mL recorded. Primary peristalsis was impaired if absent contractility or ineffective esophageal motility were diagnosed by Chicago Classification v4.0. Post-MRS augmentation was intact if distal contractile integral (DCI) exceeded mean single-swallow DCI. Multimodal peristalsis assessment classified as normal if all 3 metrics (primary and secondary peristalsis, post-MRS augmentation) intact; mild dysfunction if 1 abnormal, severe dysfunction if ≥2 abnormal. Fisher’s exact test and Chi-square were used for statistical analysis. Results: Sixty-nine patients were included (63% women, mean age 57 years, mean body mass index 26); 22 (31%) had GERD. All had FLIP, 43 had HRM data. GERD was significantly more common (47% vs 19%; P = 0.011), and mean AET was significantly higher (8.7% vs 2.7%; P = 0.012) with impaired vs intact secondary peristalsis. There was no association between GERD or AET and DI or EGJ diameter. GERD prevalence was similar with impaired vs intact primary peristalsis (22% vs 32%; P = 0.7), numerically higher with impaired vs intact MRS augmentation (39% vs 22%; P = 0.3). In multimodal analysis, GERD occurred in 17% with normal peristalsis, 33% with mild, and 43% with severe dysfunction. Mean AET rose with worsening dysfunction (2.2%, 4.5%, 4.6%). Conclusion: Impaired secondary peristalsis was significantly associated with GERD. GERD prevalence and AET are higher with dysfunction on multimodal peristaltic assessment, but not statistically significant likely due to limited sample size. Multimodal peristalsis assessment by FLIP and HRM may enhance understanding of GERD pathophysiology and inform clinical practice and larger studies are needed.