Effects of Peroral Endoscopic Myotomy on Esophageal Function in the Treatment of Achalasia

Peroral endoscopic myotomy (POEM) is a new technique to treat achalasia, but the effects on esophageal motor function and structure are still unclear. This study aimed to examine the esophageal function and anatomical changes of patients with achalasia treated with POEM. This was a retrospective study of 43 patients with achalasia treated with POEM between January 2013 and January 2016 at the Second Affiliated Hospital of Xi'an Jiaotong University. The patients were grouped as previous treatments for achalasia (n = 19) versus no previous treatment (n = 24). Surgical success (defined as Eckardt score ≤3 points or decreased by >3 points compared with baseline), recurrence, and reintervention were analyzed. Three patients (7.0%) were Eckardt grade I, 16 (37.2%) were grade II, and 24 (55.8%) were grade III. Operation time was 35 to 150 (median = 49) minutes. Both groups showed improvements in the Eckardt score after surgery (both P < .001), without a difference between the 2 groups (P = .749). The maximal mean diameter of the esophagus was reduced, and the lower esophageal sphincter pressure was improved after surgery (both groups, all P < .001), without difference between the 2 groups (all P > .05). One case of failure was probably due to the presence of an esophageal stent. POEM has a high success rate and is possibly unaffected by previous treatments, except maybe stent implantation. Clinical symptoms of achalasia are significantly relieved by POEM; the function of the esophageal sphincter and the esophagus structure are improved. Previous esophageal stent implantation could increase failure likelihood, but this will have to be confirmed.