Original article
Clinical endoscopy
Peroral endoscopic myotomy for treatment of achalasia: from bench to bedside (with video)

Presented at the Best of Digestive Disease Week Plenary Session, 2011; Chicago, Illinois (Gastrointest Endosc 2011;73:AB147).
https://doi.org/10.1016/j.gie.2012.08.018Get rights and content

Background

Peroral endoscopic myotomy (POEM) is a novel approach to performing esophageal myotomy through a long submucosal tunnel.

Objective

This study aimed to investigate the feasibility and safety of POEM for treatment of achalasia.

Design

Preclinical animal study and prospective clinical study.

Patients

Consecutive patients diagnosed with achalasia with high-resolution manometry.

Interventions

POEM was standardized for preclinical and clinical studies. After submucosal injection, a mucosal incision was made 15 cm above the gastroesophageal junction (GEJ). A long submucosal tunnel was created to extend below the GEJ. The endoscopic myotomy started 10 cm above and extended 2 cm below the GEJ. We first conducted a preclinical animal study to confirm the safety of POEM. POEM was then performed for the treatment of achalasia in humans.

Main Outcome Measurements

Relief from dysphagia assessed by the dysphagia score and Eckhardt score. High-resolution manometry and pH monitoring were performed to evaluate the posttreatment effects and esophageal acid exposure.

Results

Seven 30-kg porcine models underwent POEM in the survival study. All of the pigs survived except 1, which sustained pneumomediastinum. POEM was performed for the treatment of achalasia in 16 patients. The mean operating time was 117.0 ± 34.1 minutes. All patients tolerated food on day 2, with a contrast study confirming no leakage. The median follow-up was 176.5 days (range 98-230 days). The postoperative basal lower esophageal sphincter pressure was significantly reduced (mean reduction, 13.9 ± 14.5 mm Hg; P = .005) and 4-second integrated relaxation pressure of the GEJ (mean reduction, 10.1 ± 7.4 mm Hg; P = .001). Of these patients, 58.3% had a normalized 4-second integrated relaxation pressure, whereas 20% had excessive esophageal acid exposure after the procedure. There was a significant improvement in quality of life 6 months after POEM measured by the Short Form-36 questionnaire.

Limitation

Small sample size.

Conclusions

POEM is a feasible, safe, and effective treatment for achalasia. (Clinical trial registration number: NCT01525732.)

Section snippets

Methods

This was a prospective study of the technical development and clinical application of a novel endoscopic procedure, POEM, for the treatment of achalasia. The technical steps to perform POEM are described in the following and were the same in the procedures in both animals and humans.

Preclinical animal studies

POEM was successfully performed in 2 nonsurvival porcine models. Seven 30-kg porcine models were then used in the survival study. The mean operating time was 45.1 (± 13.5) minutes. The healing of all mucosal entrances was confirmed with no evidence of leakage on the repeat endoscopy before the postmortem examination. All pigs survived for 1 week except 1 that died immediately after the procedure. There was extensive pneumomediastinum detected on the postmortem examination that led to tension

Discussion

The current study demonstrated the feasibility and safety in translating endoscopic techniques of POEM from animal study to clinical practice. The POEM technique was based on a similar principle as that of the Heller myotomy.2, 3, 12 The mean procedure time of POEM was 117.0 minutes, which is similar to that reported from Japan and Europe.6, 13, 14 All patients had relief of dysphagia with significant improvement in Eckhardt score at 3 months after POEM. The relief of dysphagia is accompanied

Acknowledgments

We are grateful to Professor Haruhiro Inoue, Yokohama, Japan, for his contribution in proctoring the first human case of POEM and his input in the conduct of the study.

References (21)

There are more references available in the full text version of this article.

Cited by (97)

  • Endoscopic and Surgical Therapies for Achalasia

    2019, Shackelford's Surgery of the Alimentary Tract: 2 Volume Set
  • Esophageal body motility disorders

    2019, Clinical and Basic Neurogastroenterology and Motility
View all citing articles on Scopus

DISCLOSURE: The following authors disclosed financial relationships relevant to this publication: Drs Chiu and Lau served as members of a research group sponsored by Olympus. The other authors disclose no financial relationships relevant to this publication. The prototype triangle-tip knife was provided by Olympus Co Ltd at no cost.

If you would like to chat with an author of this article, you may contact Dr Chiu at [email protected].

View full text