203 RISK AND PROTECTIVE FACTORS OF GASTROESOPHAGEAL REFLUX DISEASE AFTER PERORAL ENDOSCOPIC MYOTOMY

Abstract

Abstract Peroral endoscopic myotomy(POEM)has been reported as safe and effective treatment for achalasia. This procedure is proposed to be a less invasive alternative to conventional laparoscopic Heller-myotomy with Dor-fundoplicatin(LHD), previous studies have shown that POEM may result in a higher incidence of gastroesophageal reflux disease(GERD)compared with LHD. However, certain predictors of GERD after POEM remain unstudied limiting current treatment strategy of achalasia. The aim of this study is to clarify the protective factors of GERD post-POEM. Methods Fifty-one patients who underwent POEM at our institution between January 2016 and December 2019 were included. We performed esophagogram and high-resolution esophageal manometry (HRM) as a part of preoperative evaluation. Upper gastrointestinal endoscopy has been assessed 3 months, 1 year, and then yearly after POEM. Patients were divided into two groups based on post-POEM endoscopic findings: GERD group (patients who had esophagitis [n = 28; median age 53 years with 18 male]) and non-GERD group (patients who did not have GERD [n = 23; median age 50 years with 14 male]). We compared preoperative foregut tests between the two groups. Results Twenty-eight out of 51 patients (54.9%) developed esophagitis. There were no differences in age, sex, BMI, and findings of esophagogram between the groups. Based on HRM test, greater overall lower esophageal sphincter (LES) length was noted in the non-GERD group compared with the GERD group (3.0 vs. 2.6 cm, p = 0.034). Length of gastric myotomy was comparable between the GERD and non-GERD groups (2.0 vs. 3.0 cm, p = 0.477). Similar incidence of esophagitis was evident in patients who had a history of prior LHD and those who underwent POEM as a primary intervention (60% [9/15 patients] vs. 52.8% [19/36 patients], p = 0.437). Conclusion Shorter overall LES length appears to be associated with esophagitis post-POEM. Length of gastric myotomy did not correlate to GERD in the study cohort. Prior Dor fundoplication may not avert development of GERD after POEM. Further study is warranted.