A stepwise approach for peroral endoscopic myotomy for treating achalasia: from animal models to patients.

OBJECTIVES: Peroral endoscopic myotomy (POEM) was initially developed for the treatment of achalasia. This study aimed to investigate the feasibility and safety of a stepwise approach for POEM in the management of achalasia.

METHODS: A total of five ex-vivo porcine esophagus-stomach training models were created and POEM was performed. Then, 25 patients with achalasia were treated similarly. The Eckardt score, barium esophagrams, and high-resolution manometry were used to evaluate its efficacy.

RESULTS: POEM procedures were completed in five stomach-esophagus models, with perforations in the initial three and success in the last two. A total of 25 achalasia patients (13 males, 12 females) with achalasia successfully underwent POEM. The mean operation time was 72.0 min (range, 45-180 min). There were two complications--one case each of severe bleeding and pneumothorax--that were both treated successfully. During the follow-up period, the median Eckardt score decreased dramatically from 8 to 1 (p = 0.000). The lower basal esophageal sphincter pressure decreased markedly (41.3 ± 12.6 vs. 11.3 ± 4.3 mmHg, p = 0.000), as well as the 4-s integrated relaxation pressure (37.1 ± 12.6 vs. 7.1 ± 2.4 mmHg, p = 0.000). Additionally, the maximum esophagus width was significantly reduced (mean reduced width: 1.6 ± 1.1 cm, p = 0.000).

CONCLUSIONS: The ex-vivo porcine esophagus-stomach can be used as a simple and cheap training model that mimics the POEM procedure. POEM is a safe and effective therapy for achalasia patients.