POEM vs. Pneumatic Dilation for Esophageal Achalasia

Peroral Endoscopic Myotomy Versus Pneumatic Dilation for Esophageal Achalasia: a Prospective Randomized Controlled Trial

The purpose of this study is to determine the efficacy and safety of peroral endoscopic myotomy (POEM) compared with pneumatic dilation in the treatment of esophageal achalasia.

Esophageal achalasia is an esophageal motor disorder, which is characterized by the absence of esophageal peristalsis combined with a defective relaxation of the lower esophageal sphincter (LES). The major symptoms of esophageal achalasia are dysphagia, chest pain, and regurgitation of undigested food. Currently, treatment options mainly focus on relief of the symptoms by reducing the LES pressure. Pneumatic dilation is the main endoscopic therapies for esophageal achalasia. However, the patients need repeat treatment to maintain therapeutic success and there is a risk of perforation (1%-3%). For surgery approaches, the laparoscopic Heller's myotomy (LHM) combined with Dor's antireflux procedure has gained considerable interest. The LHM can sustain therapeutic effects for long-term in approximately 80% of patients. Recently, Inoue et al. succeeded in treating achalasia endoscopically with a method called peroral endoscopic myotomy (POEM) and achieved promising results in short-term. Technically, POEM derived from natural orifice transluminal endoscopic surgery (NOTES) and endoscopic submucosal dissection (ESD), in which a submucosal tunnel is created after submucosal injection, and then an endoscopic myotomy was made at the gastroesophageal junction. However, the long-term efficacy and safety of POEM were not determined, and there was no prospective study that compared the POEM with other conventional treatment. Therefore, we aim to determine the efficacy and safety of POEM, compared with the pneumatic dilation, in the treatment of esophageal achalasia.

Entry to submucosal space. After submucosal injection, a 2-cm longitudinal mucosal incision is made at approximately 13 cm proximal to the gastroesophageal junction (GEJ). Submucosal tunnelling. A long submucosal tunnel is created to 3 cm distal to the GEJ. Endoscopic myotomy is begun at 3 cm distal to the mucosal entry point, and is carried out in a proximal to distal direction to a total length of 10 cm. Long endoscopic myotomy of inner circular muscle bundles is done, leaving the outer longitudinal muscle layer intact. The expected end point of myotomy is 2 cm distal to the GEJ. Closure of mucosal entry: the mucosal incision is closed using hemostatic clips. (Inoue H et al. POEM for esophageal achalasia… Endoscopy 2010; 42: 265-271)

A Rigiflex balloon (30 mm) was positioned at the esophagogastric junction and dilated at a pressure of 5 PSI for 1 minute, followed by 8 PSI for 1 minute. (N Engl J Med 2011;364:1807-16.)

Therapeutic success is defined as a symptom control to an Eckardt score of 3 or less. The Eckardt score is the sum of the symptom scores for dysphagia, regurgitation, and chest pain (with a score of 0 indicating the absence of symptoms, 1 indicating occasional symptoms, 2 indicating daily symptoms, and 3 indicating symptoms at each meal) and weight loss (with 0 indicating no weight loss, 1 indicating a loss of <5 kg, 2 indicating a loss of 5 to 10 kg, and 3 indicating a loss of >10 kg) (Eckardt, V. Gastroenterology, 1992. 103(6): p. 1732-8.)

The basal LES pressure and the swallow-induced LES relaxation will be monitored and measured at the end of expiration. After introduction and equilibration, basal pressure is monitored during at least 5 minutes. Swallow-induced relaxation of the sphincter is assessed by 5 ml wet swallows, at least 30 s apart.

Patients will complete the quality-of-life questionnaires (the Medical Outcomes Study 36-Item Short-Form Health Survey, SF-36) for assessing quality of life

Inclusion Criteria: Between 18 and 75 years of age Patient with esophageal achalasia Eckardt score > 3 Signed informed consent Exclusion Criteria: Severe cardio-pulmonary disease or other serious disease leading to unacceptable surgical risk Pseudo-achalasia, Mega-oesophagus (greater than 7 cm), or Oesophageal diverticula in the distal oesophagus Previous endoscopic Botox injection Previous oesophageal or gastric surgery Pregnancy or lactation women, or ready to pregnant women Not capable of filling out questionnaires

Inoue H, Minami H, Kobayashi Y, Sato Y, Kaga M, Suzuki M, Satodate H, Odaka N, Itoh H, Kudo S. Peroral endoscopic myotomy (POEM) for esophageal achalasia. Endoscopy. 2010 Apr;42(4):265-71. doi: 10.1055/s-0029-1244080. Epub 2010 Mar 30.

Boeckxstaens GE, Annese V, des Varannes SB, Chaussade S, Costantini M, Cuttitta A, Elizalde JI, Fumagalli U, Gaudric M, Rohof WO, Smout AJ, Tack J, Zwinderman AH, Zaninotto G, Busch OR; European Achalasia Trial Investigators. Pneumatic dilation versus laparoscopic Heller's myotomy for idiopathic achalasia. N Engl J Med. 2011 May 12;364(19):1807-16. doi: 10.1056/NEJMoa1010502.