Assessment of Different Modified POEM for Achalasia

Comparison Study of Conventional Peroral Endoscopic Myotomy (POEM) and Different Modified Procedures of POEM for Achalasia

The aims of this study is to compare the efficacy and safety of conventional myotomy (circular myotomy) and modified myotomy (full-thickness myotomy) in the treatment of achalasia patients.

Peroral endoscopic myotomy (POEM) is a novel clinical technique used to treat achalasia. The conventional POEM myotomy length averages 8 to 10 cm (4-6 cm in the esophagus, 2-4cm in the LES, 2cm in the cardia & 6-8 cm above and 2 cm below the gastroesophageal junction [GEJ]) for typical achalasia (Chicago classification I, II), with only the inner circular muscle layer incised.

There is still no conclusion on the thickness of muscle bundle dissection recommended during POEM. Selective circular muscle myotomy is designed to avoid gastroesophageal reflux (GER) postoperatively and decrease morbidity during POEM. But one meta-analysis showed that Heller's surgery could keep patients in long-time remission, mainly because of its full-thickness muscle bundle dissection to make sure of persist relaxation of LES. A retrospective study comparing the outcomes of full-thickness and circular muscle myotomy showed no differences in efficacy, GER or adverse events, although the procedural time was shorter in the full thickness myotomy group.

Further randomized controlled trials are warranted to assess the efficacy and safety of different modified myotomy approaches in POEM for patients with achalasia.

Inclusion Criteria:

• diagnosed as achalasia type I or II according to the Chicago Classification Version 4.0, with an Eckardt score >3
• Their age is ≥14years and ≤70 years
• Able to give written consent

Exclusion Criteria:

• undergone previous surgical treatments
• had contra-indication to general anesthesia
• previous surgery of the mediastinum, stomach, or esophagus;
• Pregnant or lactating female
• type III achalasia
• current alcohol or drug addiction, mental retardation, severe congenital or acquired coagulopathy (international normalized ratio >1.6)
• hepatic cirrhosis with or without portal hypertension, eosinophilic esophagitis (biopsies were performed at index endoscopy), or confirmed Barrett's esophagus
• esophageal diverticula or hiatal hernia based on findings from the index barium esophagram, or other conditions that the investigator believed not appropriate for POEM procedure