Post-Myotomy Septum (PoMS) Following POEM: Incidence, Clinical Outcomes, and Management in a High-Volume Center

Aims Peroral Endoscopic Myotomy (POEM) is a highly effective treatment for achalasia and other esophageal motility disorders. However, some patients may develop recurrent symptoms during the follow-up period, often related to dilation of the distal esophagus, which is radiologically referred to as “blown-out myotomy.” Endoscopically, we have observed the presence of a Post-Myotomy Septum (PoMS) in symptomatic patients. This study aims to assess the incidence of PoMS and evaluate the clinical outcomes in patients treated for this condition.

Methods A retrospective analysis was performed on patients who underwent POEM between 2012 and 2024. Patient records, including endoscopic images and videos from follow-up visits, were reviewed to identify PoMS, defined as the endoscopic presence of a distal esophageal septum, with or without an associated pseudodiverticulum. Key variables included the interval between POEM and PoMS detection, symptoms at the onset of the septum (Eckardt score), treatment strategies used, and patient response to these interventions (defined as an Eckardt score<3).

Results A total of 595 patients were analyzed, with PoMS detected in 50 patients (8.4%). Of these, 74% developed PoMS following POEM for Type II achalasia. Four patients (8%) had received prior treatment before POEM, with 74% having undergone anterior myotomy. The median time from POEM to PoMS detection was 17.5 months, with 60% of PoMS cases identified within the first year post-POEM. PoMS with Eckardt score>3 was found in 19 out of 50 patients (38%), a significantly higher proportion compared to patients with a post-POEM Eckardt score > 3 without PoMS (38% vs. 9.7%, P<0.001). A total of 10 patients with PoMS were re-treated: 8 underwent re-POEM and septotomy, and 2 had pneumatic dilations. After treatment, all patients had an Eckardt score<3 [1] [2] [3].

Conclusions PoMS is a significant complication that typically presents several months after POEM and is associated with considerable symptom burden. Early detection and appropriate treatment lead to favorable outcomes in most cases, highlighting the importance of regular endoscopic follow-up in this patient population. Further studies are required to explore the relationship between this new condition and the technical aspects of myotomy, manometry, radiological findings, and long-term outcomes.

Publication History

Article published online:
27 March 2025

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