Role of short interval FLIP panometry in predicting long-term outcomes after per-oral endoscopic myotomy.

BACKGROUND: The Eckardt score (ES) is used to assess symptom response to Per-Oral Endoscopic Myotomy (POEM), but reliable methods to assess physiologic success are needed. Functional lumen imaging probe (FLIP) panometry has a potential role in post-POEM follow-up to predict long-term outcomes. The aim of this study was to assess the correlation between clinical success and FLIP parameters following POEM to determine if short interval FLIP could predict long-term outcomes. METHODS: This was a prospective study of adult patients who underwent POEM with short interval follow-up FLIP between 11/2017 and 3/2020. Clinical success was defined as post-procedure ES ≤ 3. Physiologic success was based on an esophago-gastric junction distensibility index (EGJ-DI) > 2.8 mm2/mmHg on FLIP. RESULTS: 47 patients (55% female, mean age 55 years) were included in the study. Clinical success after POEM was seen in 45 (96%) patients (mean ES 6.5 ± 2.2 pre and 0.83 ± 1.0 post-POEM, p < 0.001). Physiologic success was noted in 43 (91.5%) patients (mean EGJ-DI 6.1 mm2/mmHg ± 2.5). Among 4 patients not meeting criteria for physiologic success, EGJ-DI was 2.5-2.6. There was no correlation between post-POEM EGJ-DI and ES in the short term or long term. Significant reflux esophagitis was seen in 6 (12.8%) patients with no difference in mean EGJ-DI with vs without esophagitis (5.9 vs 6.1, p = 0.44). CONCLUSION: Post-POEM endoscopy with FLIP is useful to both assess EGJ physiology and to examine for reflux esophagitis. Short interval FLIP has limited utility to predict long-term patient outcomes or risk of acid reflux.