S2204 Posterior Myotomy Is an Important Risk Factor for Repeat Per-Oral Endoscopic Myotomy

Introduction: Repeat peroral endoscopic myotomy (Re-POEM) is an emerging salvage therapy for patients with achalasia who experience persistent or recurrent symptoms after an initial POEM procedure. The procedure involves a second endoscopic myotomy to alleviate symptoms by further reducing the lower esophageal sphincter (LES) pressure. This study aims to understand what factors increase the chance that a patient will need the POEM procedure repeated. Methods: A cohort of patients who underwent repeat esophageal POEM at Hershey Medical Center between 2013 and 2023 was analyzed and matched with patients who had similar procedures during the same period. The study reviewed demographic, clinical, manometric, endoscopic, and POEM-related data for these patients. Results: Three hundred and eighteen patients [Male: 171 (53.8%), age (SD): 56 (18)] had POEM for achalasia or outflow obstruction over on decade. Their Eckardt score improved significantly (Pre: 7.2 vs Post: 0.8, P: < 0.01). Twelve patients, 3.8%, required repeat POEM, mostly within one year (9 patients) and were woman (58.3%). Posterior approach patient was more likely to get repeat POEM as compared to anterior approach (19% vs 3%, P: 0.005). With controlling the patient, disease, and procedure related factors, longer gastric myotomy (OR: 1.99, 95% CI: 1.03-3.88, p: 0.04) and anterior myotomy approach (OR: 0.08, 95% CI: 0.02-0.33, P: < 0.001) were independent factors predicting chance of repeat POEM. Conclusion: Repeat POEM required in 3.8% of patients mostly within first year of the index POEM. Among, patient, disease and procedure related factors, posterior myotomy approach along with longer gastric myotomy were 2 independent risk factors for repeat POEM. Result of this study require further validation with pooled cohort data from other centers.