Utility of Intraprocedural Luminal Diameter and Distensibility Measurements During the Esophageal Peroral Endoscopic Myotomy Procedure.

Goals: Through evaluation of the lower esophageal sphincter immediately before and after myotomy using an endoluminal functional lumen imaging probe (EFLIP), our study aimed to determine the clinical response to peroral endoscopic myotomy (POEM) and the incidence of postprocedure reflux.

Background: Achalasia is a rare esophageal motility disorder characterized by impaired relaxation of the lower esophageal sphincter (LES) and diminished peristalsis. POEM is a therapeutic option for durable management of achalasia. However, symptomatic acid reflux and esophagitis are well-known adverse effects of the procedure.

Study: Electronic medical records of 168 patients who underwent POEM for achalasia at 2 tertiary care referral centers from May 2014 to May 2021 were reviewed. EFLIP was used at a range of catheter fill volumes to assess LES dynamics. Preprocedure and postprocedure Eckardt Symptom Scores were recorded.

Results: Significant clinical improvement from POEM was sustained in over 94% of patients after 1 year. EFLIP changed intraprocedural management 5% of the time by means of myotomy extension. In patients with reflux>1 year following POEM, there was no significant difference in post-POEM LES diameter or change in LES diameter compared with those without reflux. However, post-POEM LES distensibility index (DI) was significantly higher in patients with reflux after 1 year compared with those without reflux.

Conclusions: POEM is a safe and increasingly effective therapy for patients with symptomatic achalasia. Intraprocedural EFLIP measurements suggest that post-POEM reflux may be correlated more with DI than LES diameter. Yet, more data is needed to substantiate these outcomes.