Full-thickness myotomy is associated with higher rate of postoperative gastroesophageal reflux disease.

Aim: To compare long-term occurrence of gastroesophageal reflux disease (GERD) between two different types of peroral endoscopic myotomy (POEM) for achalasia.

Methods: We included all patients with achalasia who underwent POEM at our hospital from August 2011 to October 2012 and had complete GERD evaluation with ≥ 3 years of follow-up. They were divided into circular or full-thickness myotomy groups according to the depth of myotomy. Demographics, Eckardt score, manometry results, 24-h pH monitoring, and GERD symptoms were recorded and compared between the two groups.

Results: We studied 56 patients (32 circular myotomy and 24 full-thickness myotomy) with complete GERD evaluation. There was no significant difference between the two groups in terms of treatment success (defined as Eckardt score ≤ 3), postoperative Eckardt score, mean basal lower esophageal sphincter pressure, and 4-s integrated relaxation pressure (4sIRP). Postoperative abnormal esophageal acid exposure was found in 25 patients (44.6%). A total of 13 patients (23.2%) had GERD symptoms and 12 had esophagitis (21.4%). Clinically relevant GERD (abnormal esophageal acid exposure associated with GERD symptoms and/or esophagitis) was diagnosed in 13 patients (23.2%). Multivariate analysis revealed that full-thickness myotomy and low level of postoperative 4sIRP were predictive factors for clinically relevant GERD.

Conclusion: Efficacy and manometry are comparable between achalasia patients treated with circular or full-thickness myotomy. But patients with full-thickness myotomy and low postoperative 4sIRP have more GERD.