dr. hiroki sato (orcid id : 0000-0001-7766-3724) prof ...€¦ · 5. fukui t, yamaguchi n. minds...

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This article has been accepted for publication and undergone full peer review but has not

been through the copyediting, typesetting, pagination and proofreading process, which may

lead to differences between this version and the Version of Record. Please cite this article as

doi: 10.1111/den.13239

This article is protected by copyright. All rights reserved.

DR. HIROKI SATO (Orcid ID : 0000-0001-7766-3724)

PROF. KAZUMA FUJIMOTO (Orcid ID : 0000-0002-1690-4165)

Article type : Review

Clinical Practice Guidelines for Peroral Endoscopic Myotomy

Haruhiro Inoue，Hironari Shiwaku，Katsuhiko Iwakiri，Manabu Onimaru,

Yasutoshi Kobayashi，Hitomi Minami，Hiroki Sato，Seigo Kitano，Ryuichi Iwakiri,

Nobuo Omura，Kazunari Murakami，Norio Fukami，Kazuma Fujimoto, Hisao Tajiri

Japan Gastroenterological Endoscopy Society

Corresponding Author:

Haruhiro INOUE, MD., PhD., FASGE.

Professor and Director,

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Digestive Diseases Center, Showa University Koto-Toyosu Hospital

Toyosu5-1-38, Koto-Ku, Tokyo, 135-8577, Japan

Tel: +81-3-6204-6064, e-mail: [email protected]

ABSTRACT

Peroral endoscopic myotomy (POEM) is a novel technique developed in Japan; it is used to

treat esophageal achalasia and esophageal motility disorders. This technique has been rapidly

accepted and widely disseminated throughout our clinical practice because of its low

invasiveness, technical novelty, and high efficacy. Since the advent of POEM, there have

been no clinical guidelines that clearly indicated its standard of care, and these guidelines

have been anticipated both nationally and internationally by clinicians who engage in POEM

practice. In 2017, to meet these needs, the Japan Gastrointestinal Endoscopy Society (JGES)

launched the guideline committee for POEM. Based on the guideline development process

proposed by the Medical Information Network Distribution Service (MINDS), the guideline

committee initially created research questions on POEM and conducted a systematic review

and meta-analysis on each topic. The clinical research extracted from databases for these

clinical questions and the systematic review mainly comprised few retrospective studies with

a small number of participants and short trial periods; hence, the strength of the evidence and

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recommendations derived from these results was low. Throughout this process, the guideline

committee met thrice: once on May 13, 2017 and again on September 17, 2017 to formulate

the draft. A consensus meeting was then held on January 14, 2018 in Tokyo to establish the

guideline statements and finalize the recommendations using the modified Delphi method.

This manuscript presents clinical guidelines regarding current standards of practice and

recommendations in terms of the nine chief topics in POEM.

INTRODUCTION

Esophageal achalasia is an esophageal motility disorder that is mainly characterized by

degeneration of the esophageal myenteric plexus. This disorder leads to a lack of peristalsis

of the esophageal body and absence or incomplete relaxation of the lower esophageal

sphincter (LES). As a result, patients with esophageal achalasia suffer from symptoms, such

as dysphagia, regurgitation, and chest pain. Traditional treatment options for esophageal

achalasia and similar motility disorders intended to weaken or disrupt the LES include

medical treatments, such as botulinum toxin injection, pneumatic balloon dilatation and

surgery, and Heller myotomy.1 In 2008, peroral endoscopic myotomy (POEM) was

developed to completely endoscopically create a longitudinal myotomy of the circular

esophageal and gastric muscle in an attempt to reduce LES pressure.2 POEM has a significant

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advantage over surgery in that not only is it a minimally invasive procedure that does not

leave visible scars, but the length of myotomy from the esophageal to the gastric side can

easily be adjusted on a case-by-case basis while achieving the functional durability of

traditional surgical myotomy.1,3

Given the increasing numbers of POEMs currently

performed in the clinical setting, medical providers have increased the need for a clinical

guideline that will provide clear and specific recommendations regarding POEM. In 2017, the

Japan Gastrointestinal Endoscopy Society (JGES) launched the guideline committee for

POEM to develop clinical guidelines based on the scientific process, including a systematic

review and meta-analysis and a consensus meeting to evaluate the resulting statements. The

JGES-POEM guideline committee sincerely hopes that these guidelines will serve as a

decision-making tool for use in the clinical setting and ultimately contribute to the global

improvement of POEM practice and patient care in achalasia-related diseases.

Guideline Development Process

Guideline committee members

The guideline committee comprised twelve gastrointestinal endoscopists, including six

members of the development committee and four members of the evaluation committee, as

shown in Table 1. The guideline committee selected the following nine topics as core

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statements for these guidelines: (i) Starting a POEM program; (ii) Training for POEM

beginners; (iii) Indications and contraindications for POEM; (iv) Preprocedural evaluation for

POEM; (v) Preparations prior to POEM procedures; (vi) POEM technique; (vii) Efficacy of

POEM; (viii) Adverse events in POEM; and (ix) Follow-up strategies after POEM. Based on

these topics, the committee created twenty-two clinical questions (CQs) relevant to POEM

procedures.

Evaluation process

The guideline development committee conducted systematic reviews to answer these CQs.

Each committee member independently searched literature pertinent to the CQs using

Medline, The Cochrane library, and the Japan Medical Abstract Society Database, from 2010,

i.e., when the first case of POEM for humans had been reported, up to April 2017, and

performed a meta-analysis, if applicable. Experts were interviewed and literature was

searched for in other databases and medical journals. With the final results of the systematic

review and a meta-analysis of the CQs, each committee member who conducted the

systematic review rated the strength of the evidence and recommendations according to the

Medical Information Network Distribution Service (MINDS) Handbook for Clinical Practice

Guideline Development (Table 2).5 Each committee member subsequently finalized the

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guideline statement for each CQ by using the strength of the evidence and recommendations

according to the Grading of Recommendations Assessment, Development and Evaluation

system.6 All guideline committee members had a consensus meeting on January 14, 2018 in

Tokyo. During this meeting, the committee used the modified Delphi method to establish the

consensus statement; each guideline statement receiving a rating on a scale of 1–3 indicated

“disagree,” 4–6 indicated “unsure,” and 7–9 indicated “agree”. The median, highest, and

lowest number of these results were recorded.4,7,8

When consensus was not achieved, the

statements were reviewed and revised, and further Delphi evaluations were conducted until

agreement was achieved (scores above 7) among the committee members.4,7,8

After the

committee produced the final draft of these guidelines, it was publicly released on the

homepage of the Japan Gastrointestinal Endoscopy Society website to accept public

comments. When these processes were complete, the committee released the final version of

the manuscript.

Target audience

These clinical guidelines apply to the endoscopic treatment of patients planning to undergo

POEM and are intended to be used by the clinicians and their supervising physicians who

engage in POEM practice. The guidelines provide basic recommendations regarding the

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current standard of care for POEM procedures; therefore, each guideline user should

carefully evaluate the backgrounds of each patient and clinician, including the patient’s

preferences, age, comorbidity, social and medical situations, and the clinician’s facilities

when they apply these recommendations to their clinical practice.

REFERENCES

1. Inoue H, Sato H, Ikeda H et al. Per-Oral Endoscopic Myotomy: A Series of 500 Patients.

J. Am. Coll. Surg. 2015; 221: 256–64.

2. Inoue H, Minami H, Kobayashi Y et al. Peroral endoscopic myotomy (POEM) for

esophageal achalasia. Endoscopy. 2010; 42: 265–71.

3. Teitelbaum EN, Soper NJ, Santos BF et al. Symptomatic and physiologic outcomes one

year after peroral esophageal myotomy (POEM) for treatment of achalasia. Surg.

Endosc. 2014; 28: 3359–65.

4. Shiffman RN, Shekelle P, Overhage JM et al. Standardized reporting of clinical practice

guidelines: a proposal from the Conference on Guideline Standardization. Ann. Intern.

Med. 2003; 139: 493–8.

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5. Fukui T, Yamaguchi N. Minds Handbook for Clinical Practice Guideline Development

2014. Igaku-shoin. 2014 (in Japanese).

6. Andrews JC, Schünemann HJ, Oxman AD et al. GRADE guidelines: 15. Going from

evidence to recommendation-determinants of a recommendation's direction and strength.

J. Clin. Epidemiol. 2013; 66: 726–35.

7. Eddy DM. Clinical decision making: from theory to practice. Designing a practice

policy. Standards, guidelines, and options. JAMA. 1990; 263: 3077–84.

8. Ueno F, Matsui T, Matsumoto T et al. Evidence-based clinical practice guidelines for

Crohn's disease, integrated with formal consensus of experts in Japan. J. Gastroenterol.

2013; 48: 31–72.

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Japan Gastroenterological Endoscopy Society Guidel ine Committee

Director and Chairman Kazuma Fujimoto (Department of Internal Medicine, Saga Medical School)

Working Committee for development of the Clin ical Practice Guidel ines for POEM

Chairman

Committee members Katsuhiko Iwakiri (Department of Gastroenterology, Nippon Medical School)

Evaluation Committee for development of the Clin ical Practice Guidel ines for POEM

Chairman Seigo Kitano (Oita University)

Committee members Ryuichi Iwakiri (Department of Medicine, Choseikai Kinosita Clinic)

Norio Fukami (Division of Gastroenterology and Hepatology, Mayo ClinicArizona)

Table 1. Committee members for development of the Clin ical Practice Guidel ines for POEM

Hitomi Minami (Department of Gastroenterology and Hepatology, NagasakiUniversity Hospital)

Kazunari Murakami (Department of Gastroenterology, Oita University Faculty ofMedicine)

Nobuo Omura (Department of Surgery, Nishisaitama-Chuo National Hospital,National Hospital Organization)

Haruhiro Inoue (Digestive Disease Center, Showa University Koto-ToyosuHospital)

Manabu Onimaru (Digestive Disease Center, Showa University Koto-ToyosuHospital)

Yasutoshi Kobayashi (Department of Gastroenterology and Hepatology, JichiMedical University)

Hiroki Sato (Division of Gastroenterology and Hepatology, Niigata UniversityMedical and Dental Hospital)

Hironari Shiwaku (Department of Gastroenterological Surgery, FukuokaUniversity)

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CLINICAL QUESTIONS AND STATEMENTS

Clinical Question: 1-１

What are the criteria to be approved as an institution authorized to perform POEM?

Statement: 1-1

In Japan, authorization criteria exist under the supervision of the Ministry of Health, Labor,

and Welfare; however, there is no global consensus regarding institutional authorization

criteria or processes in other countries.

Table 2. Evidence Level and Strength of Recommendations

Grades of Recommendation

1: Strong Recommendation

2: Weak Recommendation

N/A: Unclear Recommendation, or Recommendation Grade Can’t be Determined.

Evidence Level

A: Based on Strong Evidence

B: Based on Moderate Evidence

C: Based on Weak Evidence

D: Based on very Weak Evidence

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COMMENTARY

In Japan, the Ministry of Health, Labor, and Welfare requires the following institutional

criteria to perform POEM１:

1) Designation as a specialized institution of gastroenterology, gastroenterological surgery,

and anesthesiology;

2) More than 10 cases of POEM should have been treated;

3) At least one full-time doctor having over 5 years of clinical experience in

gastroenterological surgery or gastroenterology and more than 20 cases of esophageal

endoscopic submucosal dissection (ESD). The surgeon should have treated over 15 cases of

POEM as the primary surgeon or as an assistant (at least 5 cases as a primary surgeon);

4) More than 3 full-time doctors, including at least 1 gastroenterological surgeon on the

POEM clinical team;

5) A full-time designated specialized anesthesiologist;

6) Capability for urgent surgery.

Contrarily, the Natural Orifice Surgery Consortium for Assessment and Research POEM

White Paper Committee in the United States proposed that the POEM clinical team be

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composed of gastroenterologists and gastroenterological surgeons, and to share knowledge

and training with nurses and other clinical staff２.

REFERENCES

1. Notification No. 0304-2 issued by Health Insurance Bureau of Ministry of Health, Labor

and Welfare, dated 2016 Mar 4 [Internet]. [cited 2018 Feb 17]. Available from:

http://www.mhlw.go.jp/file.jsp?id=335826&name=file/06-Seisakujouhou-12400000-Ho

kenkyoku/0000114882.pdf

2. Stavropoulos SN, Desilets DJ, Fuchs KH et al. Per-oral endoscopic myotomy white

paper summary. Gastrointest. Endosc. 2014; 8: 1–15.

Clinical Question: 2-1

What are the recommended training and teaching programs for POEM?

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Statement: 2-1

Prior to the clinical application of POEM in humans, surgeons should observe the POEM

procedures performed by experts, and then receive hands-on training using dry laboratories,

ex vivo models, or living animals, and the first several cases should be performed under strict

supervision of experts.

COMMENTARY

We recommend acquiring POEM skills through training on living animal models (e.g.,

porcine models), in dry laboratories, or on organ models. Furthermore, observation of POEM

performed by experts is recommended, and the initial several cases should be performed

under the strict supervision of experts.

Previous studies indicate that 7–40 cases are required for endoscopists with expertise in ESD

or NOTES to achieve competency in POEM. However, each of these studies had different

parameters.

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REFERENCES

1. Eleftheriadis N, Inoue H, Ikeda H et al. Training in peroral endoscopic myotomy

(POEM) for esophageal achalasia. Ther. Clin. Risk. Manag. 2012; 8: 329–42.

2. Hernández Mondragón OV, Rascón Martínez DM, Muñoz Bautista A et al. The Per Oral

Endoscopic Myotomy (POEM) technique: how many preclinical procedures are needed

to master it? Endosc. Int. Open. 2015; 3: E559–65.

3. Ren Y, Tang X, Zhi F et al. A stepwise approach for peroral endoscopic myotomy for

treating achalasia: from animal models to patients. Scand. J. Gastroenterol. 2015; 50:

952–8.

4. Stavropoulos SN, Desilets DJ, Fuchs KH et al. Per-oral endoscopic myotomy white

paper summary. Gastrointest. Endosc. 2014; 8: 1–15.

5. Stavropoulos SN, Modayil RJ, Friedel D et al. The International Per Oral Endoscopic

Myotomy Survey (IPOEMS): a snapshot of the global POEM experience. Surg. Endosc.

2013; 27: 3322–38.

6. Teitelbaum EN, Soper NJ, Arafat FO et al. Analysis of a learning curve and predictors of

intraoperative difficulty for peroral esophageal myotomy (POEM). J. Gastrointest. Surg.

2014; 18: 92–8

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7. El Zein M, Kumbhari V, Ngamruengphong S et al. Learning curve for peroral

endoscopic myotomy. Endosc. Int. Open. 2016; 4: E577–82.

8. Kurian AA, Dunst CM, Sharata A et al. Peroral endoscopic esophageal myotomy:

defining the learning curve. Gastrointest. Endosc. 2013; 77: 719–25.

9. Patel KS, Calixte R, Modayil RJ et al. The light at the end of the tunnel: a single-operator

learning curve analysis for per oral endoscopic myotomy. Gastrointest. Endosc. 2015;

81: 1181–7.


What is the clinical indication for POEM?

Statement: 3-1

POEM is indicated for esophageal achalasia and other esophageal motility disorders.

Delphi scores: Median = 9, Lowest = 8, Highest = 9

Strength of recommendation: 2 Evidence level: B

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COMMENTARY

Esophageal achalasia is an esophageal motility disorder of unknown etiology; it is

characterized by relaxation failure of the lower esophageal sphincter (LES) and impaired

peristaltic movement of the lower esophageal body.1,2

Until the advent of peroral endoscopic

myotomy (POEM), the main treatments were pharmacotherapy, pneumatic balloon dilation,

and surgery.2-6

Surgery was the most permanent and effective treatment, and the Heller-Dor

procedure was the most commonly used approach.

POEM uses an endoscope, and unlike Heller myotomy, does not require a skin incision. The

procedure was first reported by Inoue et al. in 2008.7 Since then, it is being performed at

many institutions worldwide, and it is now one of the standard treatments for esophageal

achalasia.

Three reports from Japan investigated the many cases of POEM. Inoue et al. reported a

short-term (within 6 months of treatment) success rate of 91.3% (in a study of 500 cases, in

which success was strictly defined as an Eckardt score (ES) of ≤2 or an improvement in ES

of 4 or more points); Minami et al. reported a success rate of 100% (70 cases; success defined

as an ES of ≤3), and Shiwaku et al. reported a success rate of 99% (100 cases; success

defined as an ES of ≤3).8-10

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Regarding long-term outcomes (3 years or longer), Inoue et al. reported a success rate of

88.5% (500 cases; success defined as ES of ≤2 or an improvement in ES of 4 or more

points).8 Akintoye et al. reported that a meta-analysis of 2373 cases from 36 institutions in 12

countries revealed a success rate of 98% for POEM (95% CI, 97%–100%), which indicated

that POEM is an effective treatment for esophageal achalasia, regardless of country.11

Although POEM is reported to be effective for other esophageal motility disorders (e.g.,

diffuse esophageal spasm, jackhammer esophagus, etc.), there are only few case reports; thus,

further investigation is warranted.12-17

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REFERENCES

1. Society JE. Descriptive Rules for Achalasia of the Esophagus, June 2012: 4th Edition.

Esophagus. 2017; 14: 275–89.

2. Vaezi MF, Pandolfino JE, Vela MF. ACG clinical guideline: diagnosis and management

of achalasia. Am. J. Gastroenterol. 2013; 108: 1238–49.

3. Cox J, Buckton GK, Bennett JR. Balloon dilatation in achalasia: a new dilator. Gut.

1986; 27: 986–9.

4. Heller E. Extramukose Kardioplastik beim chronischen Kardiospasmus mit Dilatation

des Esophagus. Mitteilungen aus den Grenzgebieten der Medizin und Chirurgie. 1914;

27: 141–5.

5. Shimi S, Nathanson LK, Cuschieri A. Laparoscopic cardiomyotomy for achalasia. J. R.

Coll. Surg. Edinb. 1991; 36: 152–4.

6. Pellegrini C, Wetter LA, Patti M et al. Thoracoscopic esophagomyotomy. Initial

experience with a new approach for the treatment of achalasia. Ann. Surg. 1992; 216:

291–6.



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J. Am. Coll. Surg. 2015; 221: 256–64.

9. Minami H, Inoue H, Haji A et al. Per-oral endoscopic myotomy: emerging indications

and evolving techniques. Dig. Endosc. 2015; 27: 175–81.

10. Shiwaku H, Inoue H, Yamashita K et al. Peroral endoscopic myotomy for esophageal

achalasia: outcomes of the first over 100 patients with short-term follow-up. Surg.

Endosc. 2016; 30: 4817–26.

11. Akintoye E, Kumar N, Obaitan I, Alayo QA, Thompson CC. Peroral endoscopic

myotomy: a meta-analysis. Endoscopy. 2016; 48: 1059–68.

12. Shiwaku H, Inoue H, Beppu R et al. Successful treatment of diffuse esophageal spasm by

peroral endoscopic myotomy. Gastrointest. Endosc. 2013; 77: 149–50.

13. Louis H, Covas A, Coppens E, Deviere J. Distal esophageal spasm treated by peroral

endoscopic myotomy. Am. J. Gastroenterol. 2012; 107: 1926–7.

14. Minami H, Isomoto H, Yamaguchi N et al. Peroral endoscopic myotomy (POEM) for

diffuse esophageal spasm. Endoscopy. 2014; 46: E79–81.

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15. Khashab MA, Messallam AA, Onimaru M et al. International multicenter experience

with peroral endoscopic myotomy for the treatment of spastic esophageal disorders

refractory to medical therapy (with video). Gastrointest. Endosc. 2015; 81: 1170–7.

16. Bechara R, Ikeda H, Inoue H. Peroral endoscopic myotomy for Jackhammer esophagus:

to cut or not to cut the lower esophageal sphincter. Endosc. Int. Open. 2016; 4: E585–8.

17. Nakato R, Manabe N, Mitsuoka N et al. Clinical experience with four cases of

jackhammer esophagus. Esophagus. 2016; 13: 208–14.


Is POEM effective for straight-type esophageal achalasia?

Statement: 3-2

POEM for straight-type esophageal achalasia is effective.



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COMMENTARY

A number of reports describe the successful results and safety of POEM for straight-type

achalasia. Basically, the technical difficulty of the procedure is less with straight- than with

sigmoid-type achalasia.1-10

Therefore, it is recommended that beginners start the POEM

procedure with straight-type achalasia except for Chicago type III achalasia, which requires a

longer myotomy and a more complicated procedure caused by severe abnormal contractions

of the esophageal body and a narrow working space during the procedure.11-13

REFERENCES


esophageal achalasia*. Endoscopy. 2010; 42: 265–71.

2. Minami H, Isomoto H, Yamaguchi N et al. Peroral endoscopic myotomy for esophageal

achalasia: Clinical impact of 28 cases. Dig. Endosc. 2014; 26: 43–51.

3. Li QL, Chen WF, Zhou PH et al. Peroral endoscopic myotomy for the treatment of

achalasia: a clinical comparative study of endoscopic full-thickness and circular muscle

myotomy. J. Am. Coll. Surg. 2013; 217: 442–51.

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4. Ling T, Guo H, Zou X. Effect of peroral endoscopic myotomy in achalasia patients with

failure of prior pneumatic dilation: a prospective case-control study. J. Gastroenterol.

Hepatol. 2014; 29: 1609–13.


J. Am. Coll. Surg. 2015; 221: 256–64.

6. Sharata AM, Dunst CM, Pescarus R et al. Peroral endoscopic myotomy (POEM) for

esophageal primary motility disorders: analysis of 100 consecutive patients. J.

Gastrointest. Surg. 2015; 19: 161–70.

7. Familiari P, Gigante G, Marchese M et al. Peroral Endoscopic Myotomy for Esophageal

Achalasia: Outcomes of the First 100 Patients With Short-term Follow-up. Ann. Surg.

2016; 263: 82–7.

8. Ramchandani M, Nageshwar Reddy D, Darisetty S et al. Peroral endoscopic myotomy

for achalasia cardia: Treatment analysis and follow up of over 200 consecutive patients at

a single center. Dig. Endosc. 2016; 28: 19–26.



Endosc. 2016; 30: 4817–26.

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11. Khashab MA, Messallam AA, Onimaru M et al. International multicenter experience

with peroral endoscopic myotomy for the treatment of spastic esophageal disorders

refractory to medical therapy (with video). Gastrointest. Endosc. 2015; 81: 1170–7.

12. Stavropoulos SN, Modayil RJ, Friedel D, Savides T. The International Per Oral

Endoscopic Myotomy Survey (IPOEMS): a snapshot of the global POEM experience.

Surg. Endosc. 2013; 27: 3322–38.

13. Kahrilas PJ, Bredenoord AJ, Fox M et al. The Chicago Classification of esophageal

motility disorders, v3.0. Neurogastroenterol. Motil. 2015; 27: 160–74.


Is POEM effective for sigmoid-type esophageal achalasia?

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Statement: 3-3

POEM has been reported to be effective even for sigmoid-type achalasia. However, the

procedure should be performed by a skilled endoscopist because of the technical difficulty

due to the complex anatomical feature of the esophagus.


Strength of recommendation: 2 Evidence level: C

COMMENTARY

Sigmoid-type achalasia had been further classified into two subtypes; sigmoid-type (S1) and

advanced sigmoid-type (S2), which involves severe tortuosity of the esophagus (descriptive

rules for achalasia of the esophagus, 4th edition, Japan Esophageal Society).１ Computed

tomography is also useful to differentiate the two subtypes by recognizing double lumens in

S2.2 POEM had not been applied to the advanced-type esophageal achalasia in Inoue’s first

report.2 Subsequently, Inoue et al. applied POEM to the sigmoid-type and reported the

acceptable results in terms of safety and effectiveness.3 Hu et al. presented the results of a

prospective study that included 32 cases of sigmoid-type achalasia (sigmoid; 29, advanced

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sigmoid);2 and symptoms improved in 96.8% of the patients.

4 Haito-Chavez analyzed the

data of 1826 cases from 12 centers and reported that the sigmoid-shaped esophagus was an

independent risk factor for complications.5 Performing POEM for sigmoid-type achalasia

requires advanced skills in endoscopic interventions because of the technical difficulty due to

the tortuosity of the esophagus and inflammatory fibrous changes of the mucosa and

submucosa. Therefore, it is recommended that POEM for advanced esophageal achalasia be

performed by a highly experienced endoscopist.

REFERENCES

1. Society JE. Descriptive Rules for Achalasia of the Esophagus, June 2012: 4th Edition.

Esophagus. 2017; 14: 275–89.




J. Am. Coll. Surg. 2015; 221: 256–64.

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4. Hu JW, Li QL, Zhou PH et al. Peroral endoscopic myotomy for advanced achalasia with

sigmoid-shaped esophagus: long-term outcomes from a prospective, single-center study.

Surg. Endosc. 2015; 29: 2841–50.

5. Haito-Chavez Y, Inoue H, Beard KW et al. Comprehensive Analysis of Adverse Events

Associated With Per Oral Endoscopic Myotomy in 1826 Patients: An International

Multicenter Study. Am. J. Gastroenterol. 2017; 112: 1267.


Is POEM an effective procedure for treating esophageal achalasia after failed surgical Heller

myotomy?

Statement: 3-4

POEM is effective for patients with esophageal achalasia after failed surgical Heller

myotomy, in which short-term clinical outcomes have been favorable.



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COMMENTARY

There have been few studies reporting the safety and efficacy of POEM after failed surgical

Heller myotomy, likely due to the limited number of patients with failed Heller myotomy.1

Several single-center case series have reported that POEM after failed surgical myotomy can

be performed safely and effectively with short-term clinical success rates of 92%–100% by

avoiding the previous myotomy scar.2-5

A retrospective, multicenter cohort study compared two groups: POEM with prior surgical

Heller myotomy (HM group, n = 90) vs. POEM without prior surgical Heller myotomy

(non-HM group, n = 90). This study showed that the proportion of clinical response (defined

as a decrease in ES ≤3) was significantly lower in the HM group (81%) than in the non-HM

group (94%), but there were no significant differences in terms of safety and adverse events.6

Another prospective multicenter study (n = 51) reported that a clinical response (defined as a

decrease in ES ≤3) was achieved in 94% of the cases.7

However, long-term efficacy is yet to be determined, given there have been no clinical data

with over 3 years of follow up.

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REFERENCES

1. Moonen A, Annese V, Belmans A et al. Long-term results of the European achalasia trial:

a multicenter randomized controlled trial comparing pneumatic dilation versus

laparoscopic Heller myotomy. Gut. 2016; 65: 732–9.

2. Zhou PH, Li QL, Yao LQ et al. Peroral endoscopic remyotomy for failed Heller

myotomy: a prospective single-center study. Endoscopy. 2013; 45: 161–6.

3. Onimaru M, Inoue H, Ikeda H et al. Peroral endoscopic myotomy is a viable option for

failed surgical esophagocardiomyotomy instead of redo surgical Heller myotomy: a

single-center prospective study. J Am Coll Surg. 2013; 217: 598–605

4. Vigneswaran Y, Yetasook AK, Zhao JC et al. Peroral endoscopic myotomy (POEM):

feasible as reoperation following Heller myotomy. J. Gastrointest. Surg. 2014;18:

1071–6.

5. Fumagalli U, Rosati R, De Pascale S et al. Repeated Surgical or Endoscopic Myotomy for

Recurrent Dysphagia in Patients After Previous Myotomy for Achalasia. J. Gastrointest.

Surg. 2016; 20: 494–9.

6. Ngamruengphong S, Inoue H, Ujiki MB et al. Efficacy and Safety of Peroral Endoscopic

Myotomy for Treatment of Achalasia After Failed Heller Myotomy. Clin. Gastroenterol.

Hepatol. 2017; 15: 1531–7.

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7. (Out of the literature search period) Tyberg A, Sharaiha RZ, Familiari P et al. Peroral

endoscopic myotomy as salvation technique post-Heller: International experience. Dig.

Endosc. 2017.


Is POEM effective for other esophageal motility disorders apart from achalasia？

Statement: 3-5

Although there are some reports that mention the effectiveness of POEM for other

esophageal motility disorders apart from achalasia, there are not enough case reports.

Further investigation is needed.


Strength of recommendation: N/A Evidence level: D

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COMMENTARY

Few reports of surgical myotomy have been performed for esophageal motility disorders other

than achalasia.

Leconte et al. reported a success rate of 80% (16/20) for 20 cases in which open myotomy

and fundoplication were performed for diffuse esophageal spasm.1 In 19 cases reported by

Patti et al. that underwent thoracoscopic myotomy or laparoscopic myotomy and

fundoplication for diffuse esophageal spasm, dysphagia improved in 86% of patients, and

chest pain improved in 80%.2 A similar type of myotomy is performed in POEM, and a

number of institutions have reported that POEM is effective for diffuse esophageal spasm.3-6

Recently, there have been reports on the effectiveness of POEM for jackhammer

esophagus.7-10

In a systematic review conducted by Khan et al. (of 8 studies covering a total

of 179 cases) in which a successful result was defined as an ES of 3 or less, the success rate

was 92% for Chicago classification type III esophageal achalasia, 88% for diffuse esophageal

spasm, and 72% for jackhammer esophagus.11

The number of reports about POEM for other esophageal motility disorders is limited,

however; thus, the level of evidence is currently low. Consequently, it is desirable that extra

care be taken to obtain proper informed consent before performing POEM for other

esophageal motility disorders.

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REFERENCES

1. Leconte M, Douard R, Gaudric M, Dumontier I, Chaussade S, Dousset B. Functional

results after extended myotomy for diffuse esophageal spasm. Br. J. Surg. 2007; 94:

1113–8.

2. Patti MG, Gorodner MV, Galvani C et al. Spectrum of esophageal motility disorders:

implications for diagnosis and treatment. Arch. Surg. 2005; 140: 442–8.



4. Louis H, Covas A, Coppens E, Deviere J. Distal esophageal spasm treated by peroral

endoscopic myotomy. Am. J. Gastroenterol. 2012; 107: 1926–7.

5. Minami H, Isomoto H, Yamaguchi N et al. Peroral endoscopic myotomy (POEM) for

diffuse esophageal spasm. Endoscopy. 2014; 46: E79–81.

6. Khashab MA, Messallam AA, Onimaru M et al. International multicenter experience with

peroral endoscopic myotomy for the treatment of spastic esophageal disorders refractory

to medical therapy (with video). Gastrointest. Endosc. 2015.

7. Ko WJ, Lee BM, Park WY et al. Jackhammer esophagus treated by a peroral endoscopic

myotomy. Korean. J. Gastroenterol. 2014; 64: 370–4.

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9. Kandulski A, Fuchs KH, Weigt J, Malfertheiner P. Jackhammer esophagus:

high-resolution manometry and therapeutic approach using peroral endoscopic myotomy

(POEM). Dis. Esophagus. 2016; 29: 695–6.

10. Nakato R, Manabe N, Mitsuoka N et al. Clinical experience with four cases of

jackhammer esophagus. Esophagus. 2016; 13: 208–14.

11. Khan MA, Kumbhari V, Ngamruengphong S et al. Is POEM the Answer for Management

of Spastic Esophageal Disorders? A Systematic Review and Meta-Analysis. Dig. Dis. Sci.

2017; 62: 35–44.


Is POEM effective for patients with esophageal achalasia, as compared with pneumatic

balloon dilation or surgical myotomy?

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Statement: 3-6

The treatment outcomes of POEM for Chicago classification type I and type II esophageal

achalasia are similar to those of balloon dilation or laparoscopic surgery for esophageal

achalasia; however, POEM is better than balloon dilation or laparoscopic surgery for type III

esophageal achalasia.



COMMENTARY

A systematic review and meta-analysis of the therapeutic effects of laparoscopic surgery and

POEM reported that the treatment effectiveness was similar, although the report only covered

short-term effects.1-4

On the other hand, some reports indicate that POEM is better than

laparoscopic surgery for improving dysphagia.2,3

There are also reports, however, which note

that gastroesophageal reflux disease (GERD) is more common with POEM.2

The therapeutic effectiveness of balloon dilation, laparoscopic surgery, or botulinum toxin

injection for esophageal achalasia varies according to the type of Chicago classification, and

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the success rate is reportedly highest with type II achalasia at 91%–100%, followed by type I

at 56%–85%, and worst with type III at 29%–86%.5,6

As for POEM, there was no difference

in success rates based on the Chicago classification.7,8

REFERENCES

1. Talukdar R, Inoue H, Nageshwar Reddy D. Efficacy of peroral endoscopic myotomy

(POEM) in the treatment of achalasia: a systematic review and meta-analysis. Surg.

Endosc. 2015; 29: 3030–46.

2. Schlottmann F, Luckett DJ, Fine J, Shaheen NJ, Patti MG. Laparoscopic Heller Myotomy

Versus Peroral Endoscopic Myotomy (POEM) for Achalasia: A Systematic Review and

Meta-analysis. Ann. Surg. 2018; 267: 451–60.

3. Zhang Y, Wang H, Chen X et al. Per-Oral Endoscopic Myotomy Versus Laparoscopic

Heller Myotomy for Achalasia: A Meta-Analysis of Nonrandomized Comparative

Studies. Medicine (Baltimore). 2016; 95: e2736.

4. Patel K, Abbassi-Ghadi N, Markar S, Kumar S, Jethwa P, Zaninotto G. Peroral

endoscopic myotomy for the treatment of esophageal achalasia: systematic review and

pooled analysis. Dis. Esophagus. 2016; 29: 807–19.

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5. Pandolfino JE, Kwiatek MA, Nealis T, Bulsiewicz W, Post J, Kahrilas PJ. Achalasia: a

new clinically relevant classification by high-resolution manometry. Gastroenterology.

2008; 135: 1526–33.

6. Rohof WO, Salvador R, Annese V et al. Outcomes of treatment for achalasia depend on

manometric subtype. Gastroenterology. 2013; 144: 718–25.

7. Zhang W, Linghu EQ. Peroral Endoscopic Myotomy for Type III Achalasia of Chicago

Classification: Outcomes with a Minimum Follow-Up of 24 Months. J. Gastrointest.

Surg. 2017; 21: 785–91.

8. Kim WH, Cho JY, Ko WJ et al. Comparison of the Outcomes of Peroral Endoscopic

Myotomy for Achalasia According to Manometric Subtype. Gut. Liver. 2017; 11: 642–7.


Is POEM an effective treatment for elderly patients with esophageal achalasia?

Statement: 3-7

POEM is a safe and effective procedure for elderly patients with esophageal achalasia.

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COMMENTARY

Castell et al. reported that there are two peaks in the prevalence of esophageal achalasia: at

30-40 years of age and at older than 60 years of age.1 Gennaro et al. revealed that the

prevalence of esophageal achalasia in the elderly (older than 75 years) is four times greater

than those in middle age (younger than 45 years).2 Elderly patients with achalasia have high

risk of aspiration pneumonia due to the reflux caused by achalasia; therefore, treating

achalasia in elderly patients is crucial to prevent pneumonia and to improve their quality of

life. Li et al. found that when he performed POEM for 15 patients with achalasia older than

65 years, the efficacy was 100% (success defined as an Eckardt score (ES) of ≤3) and no

major complication was related to the procedure.3 Tang et al. found, when he retrospectively

analyzed his data regarding the efficacy of his POEM in 18 patients older than 60 years and

in 95 patients younger than 60 years, efficacy was 92.9% and 89.9% （success defined as an

ES of ≤3), respectively, with no statistically significant differences between them. There was

also no statistically significant difference in the rate of adverse events in both groups.4 Wang

at al. compared the efficacy of POEM and pneumatic balloon dilatation in patients older than

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65 years.5 In this group, the efficacy of these two procedures was 92.2% and 80.0% (success

defined as an ES of ≤3), respectively, without any major complications.5

Overall, although most of the research regarding POEM in elderly patients consisted of

observational studies with a rather small number of participants, it is assumed that POEM is

an effective and safe procedure for elderly patients. However, clinicians who intend to

perform POEM on the patients in this age group should carefully evaluate the patients’

tolerance to the endoscopic procedure and anesthesia, and it is crucial to assess whether their

elderly patients could safely undergo this procedure. It is also strongly recommended that the

POEM surgeon should have experience treating many cases of POEM to be able to overcome

the technically difficult situation in elderly patients.

REFERENCES

1. Castell DO. Esophageal disorders in the elderly. Gastroenterol. Clin. North. Am. 1990;

19: 235–54.

2. Gennaro N, Portale G, Gallo C et al. Esophageal achalasia in the Veneto region:

epidemiology and treatment. Epidemiology and treatment of achalasia. J. Gastrointest.

Surg. 2011; 15: 423–8.

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3. Li CJ, Tan YY, Wang XH et al. Peroral endoscopic myotomy for achalasia in patients

aged ≥ 65 years. World. J. Gastroenterol. 2015; 21: 9175–81.

4. Tang X, Ren Y, Gao Q et al. Peroral endoscopic myotomy is safe and effective in

achalasia patients aged older than 60 years compared with younger patients. Geriatr.

Gerontol. Int. 2017.

5. Wang X, Tan Y, Lv L et al. Peroral endoscopic myotomy versus pneumatic dilation for

achalasia in patients aged ≥65 years. Rev. Esp. Enferm. Dig. 2016; 108: 637–641.


What are the recommended diagnostic workups before POEM?

Statement: 4-1-1

Gastrointestinal upper endoscopy and a timed barium swallow are performed for the

diagnosis of esophageal achalasia and decision making prior to offering POEM.

High-resolution manometry is an additional diagnostic tool that offers Chicago classification.

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COMMENTARY

Gastrointestinal endoscopy is an essential tool in order to rule out pseudo-achalasia with

esophago-gastric junctional cancer, or achalasia-related esophageal cancer. Typical cases of

esophageal achalasia have a dilated esophagus with retained food, a smooth tapering leading

to the closed lower esophageal sphincter, and increased resistance at the esophago-gastric

junction (EGJ). Esophageal rosette (rosette-like esophageal folds appearing in the lower

esophagus) and pinstripe pattern (longitudinal superficial wrinkles observed on esophageal

mucosa) were reported as characteristic endoscopic findings of esophageal achalasia.1,2

An

endoscopic examination prior to POEM is also important to determine the amount of retained

food or liquid in the esophagus and to decide the patient’s fasting period and the necessity of

esophageal lavage before POEM.

On a timed barium swallow, typical cases of esophageal achalasia show a bird-beak image at

the EGJ, with a dilated esophageal body. In advanced cases of esophageal achalasia, severe

dilatation with stasis of food and a sigmoid-like appearance occur.

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High-resolution manometry is a novel modality to differentiate esophageal achalasia from

other similar esophageal motility disorders and to categorize the type of esophageal achalasia

as type I, II or type III based on Chicago classification.3

Especially in the early stage of esophageal achalasia, gastrointestinal endoscopy and timed

barium swallow are less sensitive for the diagnosis; however, they are complementary and

raise each another’s sensitivity.4,5

Therefore, gastrointestinal endoscopy and timed barium

swallow together with high-resolution manometry are necessary for the diagnosis of

esophageal achalasia and decision making before POEM.

REFERENCES

1. Iwakiri K, Hoshihara Y, Kawami N et al. The appearance of rosette-like esophageal folds

(“esophageal rosette”) in the lower esophagus after a deep inspiration is a characteristic

endoscopic finding of primary achalasia. J. Gastroenterol. 2010; 45: 422–5.

2. Minami H, Isomoto H, Miuma S et al. New endoscopic indicator of esophageal

achalasia: “pinstripe pattern.” PLoS One. 2015; 10: e0101833.

3. Kahrilas PJ, Bredenoord AJ, Fox M et al. The Chicago Classification of esophageal

motility disorders, v3.0. Neurogastroenterol. Motil. 2015; 27: 160–74.

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4. Francis DL, Katzka DA. Achalasia: update on the disease and its treatment.

Gastroenterology. 2010; 139: 369–74.

5. Boeckxstaens GE, Zaninotto G, Richter JE. Achalasia. Lancet. 2014; 383: 83–93.

Statement: 4-1-2

Risk assessment for general anesthesia is critical in patients with achalasia.



COMMENTARY

In some patients with esophageal achalasia, respiratory function declines due to repeated

aspiration and aspiration pneumonia, which can be evaluated before POEM by chest X-ray,

and, if necessary, computed tomography. POEM can be performed under general anesthesia;

therefore, during the medical interview, patients defined as high risk for general anesthesia or

endotracheal intubation need to receive a preoperative risk assessment. Computerized

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tomography is also important to assess the curve of sigmoid-type esophageal achalasia.1,2

The

use of anticoagulants or antiplatelet drugs and their indication should also be checked and

managed accordingly referring to a guideline before POEM.3

REFERENCES




J. Am. Coll. Surg. 2015; 221: 256–64.

3. Fujimoto K, Fujishiro M, Kato M et al. Guidelines for gastroenterological endoscopy in

patients undergoing antithrombotic treatment. Dig Endosc 2014; 26: 1-14.


What is the proper duration of fasting before POEM?

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Statement: 5-1

It is imperative to assure that no dietary liquid or food has remained in the esophagus during

POEM.


Strength of recommendation: 1 Evidence level: D

COMMENTARY

Large amounts of food frequently remain in the esophagus after routine fasting for upper

endoscopy in patients with achalasia.1 Cleansing of the esophagus before POEM is essential

in order to prevent the contamination of the esophageal remnants into the mediastinum or

thoracic/abdominal cavity. Proper preparation, such as a few days of fasting and endoscopic

cleansing should be provided before POEM, especially for patients with sigmoid type.2 To

ensure the safety of POEM, preparation should be decided carefully depending on

preoperative endoscopy and/or CT scan.

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REFERENCES

1. Tanaka E, Murata H, Minami H, Sumikawa K. Anesthetic management of peroral

endoscopic myotomy for esophageal achalasia: a retrospective case series. J. Anesth.

2014; 28: 456–9.

2. Inoue H, Tianle KM, Ikeda H et al. Peroral endoscopic myotomy for esophageal

achalasia: technique, indication, and outcomes. Thorac. Surg. Clin. 2011; 21: 519–25.



Surg. Endosc. 2013.


Is CO2 insufflation required during POEM?

Statement: 6-1

POEM must be performed with CO2 insufflation. Air insufflation should never be used.

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COMMENTARY

If POEM is performed with air insufflation, given air is absorbed more slowly than CO2, the

risks are higher for gas embolism, severe pneumothorax, subcutaneous emphysema, and

abdominal compartment syndrome, which could be fatal.1-4

Air insufflation is therefore

contraindicated; CO2 insufflation should always be used. However, gas embolism,

pneumothorax, subcutaneous emphysema, and abdominal compartment syndrome can still

occur even with CO2 insufflation. Therefore, when deterioration in circulatory and/or

respiratory function is observed during POEM, the procedure should be temporarily stopped

and the cause of the problem investigated. When high-pressure (tension) pneumoperitoneum

occurs due to excessive CO2 insufflation through the submucosal endoscope, an abdominal

puncture with a needle is a simple but effective solution to decompress intra-abdominal

pressure.

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REFERENCES

1. ASGE Technology Committee, Lo S, Fujii-Lau L et al. The use of carbon dioxide in

gastrointestinal endoscopy. Gastrointest. Endosc. 2016; 83: 857–65.


J. Am. Coll. Surg. 2015; 221: 256–64.

3. Zhang XC, Li QL, Xu MD et al. Major perioperative adverse events of peroral

endoscopic myotomy: a systematic 5-year analysis. Endoscopy. 2016; 48: 967–78.




What kind of anesthesia should be selected for POEM?

Statement: 7-1

General anesthesia with endotracheal intubation should be used.

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COMMENTARY

Anesthesia induction

Even if the esophagus is cleaned the day before POEM and the patient has fasted, some

residual fluid (mainly saliva) can sometimes accumulate in the esophagus on the day of the

procedure. In this case, anesthesia induced normally could lead to aspiration. To prevent

aspiration, it is recommended that rapid induction with cricoid pressure be used and extra

caution be taken to prevent regurgitation from the esophagus into the oropharynx.1-3

Anesthesia during surgery

The CO2 insufflation systems for POEM are different from those used for laparoscopic

surgery: they are not able to automatically adjust the flow rate and maintain a constant

pressure.

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The lumen of the esophagus can communicate with the mediastinum, thoracic cavity, and

abdominal cavity after myotomy is performed; thus, continuous CO2 insufflation could cause

serious pneumomediastinum, pneumothorax, and pneumoperitoneum. To maintain proper

cardiopulmonary function and status, positive pressure ventilation should be delivered via an

endotracheal tube while general anesthesia is maintained.

The level of pneumoperitoneum should be examined regularly during surgery, and if it is

sufficient to affect circulatory dynamics, consider early paracentesis to remove the air.4 See

the Managing Pneumoperitoneum section for details.

REFERENCES

1. Yang D, Pannu D, Zhang Q, White JD, Draganov PV. Evaluation of anesthesia

management, feasibility and efficacy of peroral endoscopic myotomy (POEM) for

achalasia performed in the endoscopy unit. Endosc. Int. Open. 2015; 3: E289–95.

2. Loser B, Werner YB, Punke MA et al. Anesthetic considerations for patients with

esophageal achalasia undergoing peroral endoscopic myotomy: a retrospective case series

review. Can. J. Anaesth. 2017; 64: 480–8.

3. Stavropoulos SN, Desilets DJ, Fuchs KH et al. Per-oral endoscopic myotomy white paper

summary. Gastrointest. Endosc. 2014; 80: 1–15.

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Which patient’s position is most appropriate for POEM?

Statement: 7-2

POEM is performed in the supine position or the semi-left lateral decubitus position.



COMMENTARY

As a rule, POEM is performed in the supine position or in the semi-left lateral decubitus

position.1-3

Performing the procedure in one of these positions allows the procedure to reflect

data from the preoperative CT and allows paracentesis to be performed promptly and safely if

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tension pneumoperitoneum occurs. Exposing the upper abdomen during the procedure is also

needed to monitor the degree of pneumoperitoneum.

REFERENCES





Surg Endosc. 2013.




How should pneumoperitoneum be managed when it occurs during POEM?

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Statement: 7-3

If the degree of pneumoperitoneum is sufficient to affect circulation, then paracentesis should

be performed to remove the gas.



COMMENTARY

Pneumoperitoneum frequently occurs with POEM because the procedure involves cutting

muscles in the esophagus and the stomach. Therefore, POEM must be performed with CO2

insufflation (see the section on CO2 insufflation). The upper abdomen should be exposed

during POEM to monitor the degree of pneumoperitoneum. It is also strongly recommended

that the surgeon, surgical assistant, nurse, or anesthesiologist regularly check that CO2, not

air, is being used, and check for evidence of severe pneumoperitoneum.1 If only a minor level

of pneumoperitoneum is present, it is possible to temporarily pause the POEM procedure and

wait until the CO2 is absorbed; however, when the level of pneumoperitoneum present is

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sufficient to affect circulatory dynamics, paracentesis should be performed to remove the

gas.2,3

REFERENCES

1. Phalanusitthepha C, Inoue H, Ikeda H, Sato H, Sato C, Hokierti C. Peroral endoscopic

myotomy for esophageal achalasia. Ann. Transl. Med. 2014; 2: 31.





Multicenter Study. Am. J. Gastroenterol. 2017.


How should the length and location of the myotomy in POEM be determined?

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Statement: 7-4

The starting point of the myotomy is the oral side of the abnormal luminal obstructive

contractions in the esophageal body and the end point is 1-2 cm into the gastric side to secure

the LES incision.

The recommended location of the myotomy is the anterior or posterior wall.



COMMENTARY

The ability to freely adjust the length and location of the myotomy is one of the

characteristics of POEM. To determine the starting point of the myotomy, the responsible

segment should be identified based on information gained from patient interviews,

esophagography, upper GI endoscopy, and esophageal manometry. A myotomy is performed

from the oral side of the responsible part of the esophageal body to 1-2 cm into the gastric

side to secure the LES incision. The myotomy often needs to be longer than usual in cases of

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Chicago classification type III achalasia, diffuse esophageal spasm, or jackhammer

esophagus.1-4

If the myotomy is performed on the lateral side, diverticula after POEM can occur because

the anatomical support in the lateral side of the esophagus is weak. To prevent diverticula

after POEM, the myotomy should be performed on the anterior or posterior wall, where the

anatomical support is strong. However, in cases where the myotomy cannot be performed on

the anterior or posterior side due to scars from esophagitis or from previous treatment, this

might not apply.

The membranous portion of the trachea is located at the front of the upper thoracic

esophagus. Performing a myotomy in this area could cause a tracheoesophageal fistula; thus,

the best location for long myotomy that includes the upper thoracic esophagus is the posterior

side. In the case of sigmoid-type achalasia, the location and the course of the esophagus can

be abnormal; therefore, it should be examined with a CT scan before POEM to obtain

anatomical information surrounding the esophagus.

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REFERENCES

1. Pandolfino JE, Kwiatek MA, Nealis T, Bulsiewicz W, Post J, Kahrilas PJ. Achalasia: a

new clinically relevant classification by high-resolution manometry. Gastroenterology.

2008; 135: 1526–33.



3. Khashab MA, Messallam AA, Onimaru M et al. International multicenter experience with

peroral endoscopic myotomy for the treatment of spastic esophageal disorders refractory

to medical therapy (with video). Gastrointest. Endosc. 2015.




How should complete incision in the lower esophageal sphincter (LES) be confirmed?

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Statement: 7-5

The myotomy should continue up to 1-2 cm into the stomach to ensure that the lower

esophageal sphincter (LES) is incised and dissected properly. You should select a method to

verify that the myotomy is extended to the gastric side at proper length.



COMMENTARY

In POEM, as in the Heller myotomy, it is crucial to completely incise the lower esophageal

sphincter (LES). In the Heller myotomy, the myotomy extends to 1-2 cm into the stomach to

ensure the effectiveness of the procedure.1 POEM and the Heller myotomy are based on the

same concepts; and in POEM, the myotomy should also extend down into the stomach.

Because POEM is performed from inside the esophagus, it is more difficult to determine

whether the surgery is being performed on the gastric side, compared with the Heller

myotomy. Due to this, the techniques below are used to verify that the surgery is proceeding

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on the gastric side.2-8

The double-scope method is particularly useful because it allows direct

vision to verify that the myotomy extends down to the stomach.9,10

The Double-Scope Method

① A second scope (a transnasal endoscope) is inserted into the stomach to observe the

cardia region. If the POEM procedure has reached the gastric side, then the light from the

main scope will be visible from the stomach. The myotomy is extended 1-2 cm into the

stomach using the diameter of the main scope (approximately 1 cm) as a scale.

Endoscope Insertion Depth

② The distance from the incisors to the esophago-gastric junction is measured before

POEM is performed, and the measurement is used as a gage for the position of the scope

in the submucosal tunnel. However, this method is not always accurate in cases in which

the esophagus is bent in a sigmoid shape because the scope becomes bent.

Anatomical Landmarks

③ The submucosal blood vessels are observed from inside the submucosal tunnel and the

transition from the palisade vessels (which anatomically correspond to the LES) to the

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reticular vessel on the gastric side is noted. The spindle vein in the gastric cardia is a

specific anatomical landmark of the stomach.

④ The part of the oblique muscle and the large vessels (the branch of left gastric artery) can

be observed after entering the gastric side (the lesser curvature of the stomach); but

sometimes, depending on the orientation of the submucosal tunnel, these cannot be

observed.

Scope Resistance

⑤ When creating the submucosal tunnel, it is possible to note the narrowing of the

esophageal lumen closer to the LES and it then opening wide in the stomach.

⑥ If the scope is inserted into the stomach cavity after the myotomy is completed, then it is

possible to feel the reduced resistance at the LES.

Another method of observing the gastric side is to inject indocyanine green solution into the

submucosa on the gastric side beforehand so that it is possible to see by the change in color

when the gastric side has been reached.4

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REFERENCES

1. Oelschlager BK, Chang L, Pellegrini CA. Improved outcome after extended gastric

myotomy for achalasia. Arch. Surg. 2003; 138: 490–5.




J. Am. Coll. Surg. 2015; 221: 256–64.

4. Minami H, Inoue H, Haji A et al. Per-oral endoscopic myotomy: emerging indications

and evolving techniques. Dig. Endosc. 2015; 27: 175–81.

5. Bechara R, Onimaru M, Ikeda H, Inoue H. Per-oral endoscopic myotomy, 1000 cases

later: pearls, pitfalls, and practical considerations. Gastrointest. Endosc. 2016; 84: 330–8.



Endosc. 2016.

7. Tanaka S, Kawara F, Toyonaga T et al. Two penetrating vessels as a novel indicator of

the appropriate distal end of per-oral endoscopic myotomy. Dig. Endosc. 2017.

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9. Baldaque-Silva F, Marques M, Vilas-Boas F, Maia JD, Sa F, Macedo G. New

transillumination auxiliary technique for peroral endoscopic myotomy. Gastrointest.

Endosc. 2014; 79: 544–5.

10. Grimes KL, Inoue H, Onimaru M et al. Double-scope per oral endoscopic myotomy

(POEM): a prospective randomized controlled trial. Surg. Endosc. 2016; 30: 1344–51.


What is the standard postoperative care after POEM?

Statement: 7-6

Vital signs must be monitored on the day of POEM. As a rule, upper GI endoscopy and

esophagography should be performed after POEM, and an oral diet can be resumed after

confirmation of no leak or adverse event.

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COMMENTARY

Vital signs must be monitored on the day of POEM. Patients may drink water after they have

regained consciousness. Postoperative pain should be controlled appropriately with

analgesics.1 Given that a decreased blood oxygen level is sometimes observed as a result of

shallow breathing due to pain or compression atelectasis due to pleural effusion, oxygen

should be administered as required. Chest X-rays should be considered periodically during

hospitalization to monitor for pleural effusion, atelectasis, and pneumothorax. CT scans

should be considered if any doubts arise.2

As a rule, an upper GI endoscopy and esophagography should be performed to evaluate the

esophagus and the stomach.3 During upper GI endoscopy, check for mucosal damage or

hemorrhage and that the clips are still intact and in place. If there are no issues, then a barium

esophagogram should be taken. Verify that the contrast agent flows from the esophagus into

the stomach properly and that there is no leakage into the mediastinum. If these tests show no

problems, then meals can be resumed. Given there is the chance that clips might be dislodged

or delayed perforation of the mucosa might occur, you should pay close attention to vital

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signs, temperature, and condition of the patient. If defervescence is not observed after 3 days,

then further investigation is recommended.

REFERENCES

1. Hungness ES, Teitelbaum EN, Santos BF et al. Comparison of perioperative outcomes

between peroral esophageal myotomy (POEM) and laparoscopic Heller myotomy. J.

Gastrointest. Surg. 2013; 17: 228–35.






What type of adverse events can occur with POEM?

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Statement: 8-1

Adverse events associated with POEM include mucosal injury, mediastinitis caused by

mucosal perforation, and submucosal hematoma after POEM.


COMMENTARY

The main adverse events associated with POEM include mucosal injury, mucosal perforation,

hemorrhage (massive hemorrhage during POEM, submucosal hematoma after POEM),

pneumothorax, and pleural effusion. According to a meta-analysis by Akintoye et al.,

mucosal injury occurred in 4.8% of cases (95% CI, 2.0–8.5), mucosal perforation in 0.2%

(95% CI, 0.0-0.1), hemorrhage (massive hemorrhage) in 0.2% (95% CI, 0.0–1.4),

pneumothorax in 1.2% (95% CI, 0.1–4.3), and pleural effusion in 1.2% (95% CI, 0.0–8.3).1

Furthermore, Haito-Chavez et al. reported in a multicenter study (12 institutions; 1826 cases)

that mucosal injury occurred in 2.8% of cases, mucosal perforation in 0.7%, intraoperative

hemorrhage in 0.3%, postoperative hemorrhage in 0.2%, pneumothorax in 0.1%, and pleural

effusion in 0.2%.2

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Mucosal perforations that occur in the early postoperative period could lead to mediastinitis

or peritonitis due to the connection between the intestinal lumen and the mediastinum or the

abdominal cavity; thus, perforations must be carefully managed. Conservative treatment is

appropriate if the inflammation is localized and the patient is in stable condition. Depending

on the patient’s clinical evolution, the proper timing for surgical therapy should not be

missed, as there is the possibility that a delay in surgical therapy could lead to a patient in

critical condition. Intraoperative hemorrhage can be severe if the branch of the left gastric

artery on the gastric side is injured.3 Therefore, a blind maneuver should not be performed

when operating on the gastric side. The cause of pneumothorax is somewhat unclear, but after

the incision in the mucosa is closed, it is naturally relieved as the CO2 is absorbed. Pleural

effusion and any compression atelectasis resulting from its accumulation will improve as the

condition of the patient and the inflammation improve. If improvement is slow, then consider

evaluation with a CT scan and performing chest drainage as necessary.

REFERENCES



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Multicenter Study. Am. J. Gastroenterol. 2017.


J. Am. Coll. Surg. 2015; 221: 256–64.


How should gastroesophageal reflux disease (GERD) after POEM be managed?

Statement: 8-2

After POEM, a medical interview and an upper GI endoscopy should be conducted to assess

GERD and acid secretion inhibitors should be started as necessary.



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COMMENTARY

When a Heller myotomy is performed, fundoplication (usually the Dor procedure) is added to

prevent regurgitation from the stomach into the esophagus.1 However, few surgical studies

2-4

have reported that limited hiatal dissection during Heller myotomy reduces the incidence of

post-surgical GERD by <10%, whereas complete dissection of phreno-esophageal ligament

induces around 30%–50% reflux. This suggests that POEM in which phreno-esophageal

ligament is completely preserved seems to have less incidence of GERD.5

In addition, some

authors have reported similar incidence of GERD after either POEM or Heller Dor

surgery.6-10

Nevertheless, others have reported that after POEM abnormal acid exposure, pH

reaches 43% or 39%, although symptomatic GERD remain 8.5% and erosive esophagitis

13%–19%.11-14

As reasons for this discrepancy, two factors are considered; prolonged

extended myotomy of the gastric wall and dissection of collar sling muscle which suspends

His angle.15

To avoid these concerns, double scope method16,17

is strongly recommended.

Double scope method can control and avoid not only incomplete myotomy but also prevents

prolonged myotomy toward gastric side by direct visualization of tip of submucosal

endoscope through pediatric scope in the stomach.

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1. Stefanidis D, Richardson W, Farrell TM, Kohn GP, Augenstein V, Fanelli RD. SAGES

guidelines for the surgical treatment of esophageal achalasia. Surg. Endosc. 2012; 26:

296–311.

2. Aleksandar PS, Nebojsa S, Radovanovic S et al. Significance of limited hiatal dissection

in surgery for achalasia. J. Gastrointest. Surg. 2010; 14: 587–93

3. Robert M, Poncet G, Mion F et al. Results of laparoscopic Heller myotomy without

anti-reflux procedure in monocentric prospective study of 106 cases. Surg. Endosc.

2008; 22: 866–74

4. Zurita LC, Pescarus R, Hsich T et al. Laparoscopic limited Heller myotomy without

anti-reflux procedure does not induce significant long-term gastreoesophageal reflux.

Surg. Endosc. 2015; 29:1462–8.



6. Bhayani NH, Kurian AA, Dunst CM et al. A comparative study on comprehensive,

objective outcomes of laparoscopic Heller myotomywith per-oral endoscopic myotomy

(POEM) for achalasia. Ann. Surg. 2014; 259: 1098–103

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7. Peng L, Tian S, Du C et al. Outcome of peroral endoscopic myotomy (POEM) for

treating achalasia compared with laparoscopic Heller myotomy (LHM). Surg. Laparosc.

Endosc. percutan. Tech. 2017; 27: 60–4

8. Schneider AM, Louei BE Warren HF et al. A matched comparison of per oral endoscopic

myotomy to laparoscopic Heller myotomy in the treatment of achalasia. J. Gastrointest.

Surg. 2016; 20: 1789–96.

9. Awaitz A, Yunus RM, Khan S et al. Systematic review and meta-analysis of perioperative

outcomes of peroral endoscopic myotomy (POEM) and laparoscopic Heller myotomy

(LHM) for achalasia. Surg. Laparosc. endosc. Percutan. Tech. 2017; 27: 123–31

10. Hungness ES, Sternbach JM, Teitelbaum EN et al. Per-oral endoscopic myotomy

(POEM) after the learning curve. Ann. Surg. 2016; 264: 508–17

11. Akintoye E, Kumar N, Obaitan I et al. Peroral endoscopic myotomy: a meta-analysis.

Endoscopy. 2016; 48: 1059–68.

12. Familiari P, Greco S, Gigante G et al. Gastroesophageal reflux disease after peroral

endoscopic myotomy: Analysis of clinical, procedural and functional factors, associated

with gastroesophageal reflux disease and esophagitis. Dig. Endosc. 2016; 28: 33–41.

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13. Schlottmann F, Luckett DJ, Fine J et al. Laparoscopic Heller Myotomy Versus Peroral

Endoscopic Myotomy (POEM) for Achalasia: A Systematic Review and Meta-analysis.

Ann. Surg. 2018; 267: 451–60

14. Repici A, Fuccio L, Maselli R et al. GERD after per-oral endoscopic myotomy as

compared with Heller's myotomy with fundoplication: a systematic review with

meta-analysis. Gastrointest. Endosc. 2018; 87: 934–43

15. Shiwaku H, Inoue H, Sasaki T et al. A prospective analysis of GERD after POEM on

anterior myotomy. Surg. Endosc 2016; 30: 2496–504

16. Baldaque-Silva F, Marques M, Vilas-Boas F, Maia JD, Sá F, Macedo G. New

transillumination auxiliary technique for peroral endoscopic myotomy. Gastrointest.

Endosc. 2014; 79: 544–45.

17. Grimes KL, Inoue H, Onimaru M, et al. Double-scope per oral endoscopic myotomy

(POEM): a prospective randomized controlled trial. Surg. Endosc. 2016; 30: 1344–51.


What are the recommended follow-up strategies post-POEM?

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Statement: 9-1

Medical interview and gastrointestinal endoscopy are to be performed periodically.



COMMENTARY

At present, the duration, interval, and modality (gastrointestinal endoscopy, barium swallow,

and manometry) to monitor post-POEM patients are institution- or patient-based decisions. In

general, medical interview and gastrointestinal endoscopy (if necessary, together with barium

swallow and high-resolution manometry) are performed 2-3 months postprocedure, then

yearly. At the medical interview, esophageal symptoms (dysphagia and chest pain), the

amount of meals consumed, and changes

in body weight need to be compared pre- and postoperatively. On gastrointestinal endoscopy,

the opening of the esophago-gastric junction should be checked and compared with that at

pre-POEM. Reflux esophagitis is a frequently observed post-POEM adverse event, which

should be evaluated along with heartburn at the medical interview.

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Patients with esophageal achalasia are at increased risk for esophageal cancer, which should

also be carefully assessed. However, the best methods of follow up after treatment of

achalasia are not yet standardized.1,2

REFERENCES

1. Dunaway PM, Wong RK. Risk and surveillance intervals for squamous cell carcinoma in

achalasia. Gastrointest. Endosc. Clin. N. Am. 2001; 11: 425–34.

2. Leeuwenburgh I, Scholten P, Alderliesten J et al. Long-term esophageal cancer risk in

patients with primary achalasia: a prospective study. Am. J. Gastroenterol. 2010; 105:

2144–9


Is POEM a safe procedure and an effective treatment for esophageal achalasia in short-, mid-,

and long-term?

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Statement: 9-2

POEM is safe and effective for esophageal achalasia with promising short-term clinical

success.



COMMENTARY

Akintoye E et al. reported in their meta-analysis that clinical success (Eckardt score ≤3) was

achieved in 98% of patients after POEM. The mean Eckardt score decreased from 6.90 ± 0.15

preoperatively to 1.00 ± 0.08 within 1 year. Perioperative adverse events reported are

mucosal injury (4.8%), esophageal perforation (0.2%), substantial hemorrhage requiring

interventions (0.2%), subcutaneous emphysema (7.5%), pneumothorax (1.2%),

pneumomediastinum (1.1%), pneumoperitoneum (6.8%), and pleural effusion (1.2%). After a

mean follow up of 8 months after POEM, the rate of symptomatic gastroesophageal reflux

and esophagitis on gastrointestinal endoscopy was 8.5% and 13%, respectively.1

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A few reports are available on the long-term effect (more than a year) after POEM. Inoue et

al. reported that clinical success (Eckardt score ≤2, or reduced more than 4 points) was 91%

at 1–2 years, and 88.5% at 3 years.2 Teitelbaum EN et al. reported that clinical success

(Eckardt score ≤2) was 83% at post-5 years.3 Further studies with long-term follow up

including larger sample sizes are needed.

REFERENCES

1. Akintoye E, Kumar N, Obaitan I et al. Peroral endoscopic myotomy: a meta-analysis.

Endoscopy. 2016; 48: 1059–68.


J. Am. Coll. Surg. 2015; 221: 256–64.

3. Teitelbaum EN, Dunst CM, Reavis KM et al. Clinical outcomes five years after POEM

for treatment of primary esophageal motility disorders. Surg. Endosc. 2018; 32: 421–7.

AUTHORS’ CONFLICTS OF INTEREST IN RELATION TO THE PRESENT

ARTICLE

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With regard to the conflicts of interest of the committee members involved in the preparation

and evaluation of the present guidelines, each member was requested to make a declaration:

1) Companies/groups associated with the present guidelines from which committee members

or their family dependents living with the committee members received any remuneration as

individuals:

Executive/adviser (≥1000000 yen), stocks (≥1000000 yen), patent royalties (≥1000000 yen),

lecture fees (≥500000 yen), manuscript fees (≥500000 yen), research funds (under

individual’s name ≥ 1000000 yen), and other remuneration (≥1000000 yen).

AstraZeneca; EA Pharma Co., Ltd.; Eisai Co., Ltd; Otsuka Pharmaceutical Co., Ltd.;

Olympus Co.; Gray Healthcare Japan Inc.; Daiichi Sankyo Co., Ltd.; Takeda Pharmaceutical

Co., Ltd.; Tsumura Co., Ltd; Top Co.; and Medical Review Co., Ltd.

2) Companies/groups associated with the present guidelines that are involved in cooperative

industrial activities (except for clinical trials) with the committee members’ affiliated

departments:

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Donated courses (≥1 000 000 yen), joint research/commission fees (≥1 000 000 yen), transfer

of licenses/rights (≥1 000 000 yen), scholarship donations (≥1 000 000 yen).

Asahi Kasei Medical Co., Ltd.; Astellas Pharma Inc.; AstraZeneca; EA Pharma Co.; Eisai

Co.; Olympus Co., Otsuka Pharmaceutical Co., Ltd., Johnson & Johnson K.K., JIMRO Co.,

Ltd, Daiichi Sankyo Co., Ltd.; Takeda Pharmaceutical Co., Ltd.; Fujifilm Co.; Fujifilm

Medical Co., Ltd.; Boston Scientific Co.

FUNDING

Costs associated with the formulation of the present guidelines were subsidized by Japan

Gastroenterological Endoscopy Society (JGES).

Address for offprint requests: Japan Gastroenterological Endoscopy Society (JGES),

Shin-ochanomizu Urban Trinity Bldg 4F, 3-2-1 Kandasurugadai, Chiyoda-ku, Tokyo

101-0062, Japan.

dr. hiroki sato (orcid id : 0000-0001-7766-3724) prof ...€¦ · 5. fukui t, yamaguchi n. minds...

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