Reflux and Other Esophageal Acidification Patterns in Achalasia Patients With Reflux Esophagitis After Peroral Endoscopic Myotomy

Background/Aims: Peroral endoscopic myotomy (POEM) is an effective and safe treatment for patients with achalasia; however, it is associated with reflux esophagitis after treatment.This study aimed to examine underlying acidification patterns in patients with achalasia with reflux esophagitis after POEM.Methods: Data were used from a large multicenter randomized controlled trial comparing the effects of POEM and pneumatic dilation in treatment of naive patients with achalasia.Gastroduodenoscopy and 24-hour pH-impedance testing were performed 1 year post-POEM.Acid exposure time (AET), mean pH, minimum pH, and acidification patterns such as reflux, acid fermentation and stasis of acidic foods were compared between patients with endoscopically proven gastroesophageal reflux disease (GERD; LA grade B-D) and those without.Results: In total 38 patients were included of which 9 had endoscopically proven GERD (23.7%).AET and mean pH levels were not different between patients with and without proven GERD (14.5% vs. 6.0%,P = 0.636 and 5.4 vs. 5.2, P = 0.747, respectively).Patients with reflux esophagitis grade B-D reached lower minimum pH (1.5 vs. 2.1, P = 0.024) and had significantly longer episodes of reflux with delayed clearance, particularly in the supine position (7.7% vs. 0.0%, P = 0.041).Acid fermentation was seen in a large proportion of patients, but was not significantly different between patients with and without proven GERD (10.2% vs. 0.4%, P = 0.343).Conclusions: Reflux with delayed clearance in supine position appeared to be the dominant acidification pattern in patients with achalasia and reflux esophagitis after POEM.