Learning curve for peroral endoscopic myotomy

Curriculum for training in peroral endoscopic myotomy (POEM) in Europe (Part I): European Society of Gastrointestinal Endoscopy (ESGE) Position Statement

Peroral endoscopic myotomy (POEM) is an advanced endoscopic procedure that has become a first-line treatment for esophageal achalasia and other esophageal spastic disorders. Structured training is essential to optimize the outcomes of this technique. The European Society of Gastrointestinal Endoscopy (ESGE) has recognized the need to formalize and enhance training in POEM. This Position Statement presents the results of a systematic review of the literature and a formal Delphi process, providing recommendations for an optimal training program in POEM that aims to produce endoscopists competent in this procedure. In a separate document (POEM curriculum Part II), we provide technical guidance on how to perform the POEM procedure based on the best available evidence. 1: POEM trainees should acquire a comprehensive theoretical knowledge of achalasia and other esophageal motility disorders that encompasses pathophysiology, diagnostic tool proficiency, clinical outcome assessment, potential adverse events, and periprocedural management. 2: Experience in advanced endoscopic procedures (endoscopic mucosal resection and/or endoscopic submucosal dissection [ESD]) is encouraged as a beneficial prerequisite for POEM training. 3: ESGE suggests that POEM trainees without ESD experience should perform an indicative minimum number of 20 cases on ex vivo or animal models before advancing to human POEM cases with an experienced trainer. 4: ESGE recommends that the trainee should observe an indicative minimum number of 20 live cases at expert centers before starting to perform POEM in humans. 5: The trainee should undertake an indicative minimum number of 10 cases under expert supervision for the initial human POEM procedures, ensuring that trainees can complete all POEM steps independently. 6: ESGE recommends avoiding complex POEM cases during the early training phase. 7: POEM competence should reflect the technical success rate, both the short- and long-term clinical success rates, and the rate of true adverse events. 8: A POEM center should maintain a prospective registry of all procedures performed, including patient work-up and outcomes, procedural techniques, and adverse events.

Complications related to third space endoscopic procedures

Third space endoscopy (TSE) encompasses a breadth of procedures for the treatment of a variety of GI disorders. The widespread use of per-oral endoscopic myotomy (POEM) and its diversification to include extended indications and at locations other than the oesophagus has provided an insight into the potential complications encountered. The most common adverse events associated with POEM, the epitome of TSE procedures, include insufflation related injuries, bleeding, failure of mucosal barrier, infections, pain, blown out myotomy and gastroesophageal reflux disease. The purpose of this review is to highlight the pitfalls and to identify the risk factors that may lead to adverse events, and to recommend appropriate salvage interventions in the scope of the current evidence.

Navigating the learning landscape: Comprehensive training in third space endoscopy - training, techniques, and practical recommendations

Third space endoscopy (TSE), including ESD, POEM, or STER are advanced procedures requiring precise endoscopic control and tissue recognition. Despite its increasing adoption, evidence-based curricula, and standardized training protocols for TSE are lacking. This review explores training methods, cognitive skills, and technical proficiency requirements for endoscopists performing TSE, with a primary emphasis on POEM. Generally, it seems wise to recommend a step-up approach to TSE training, starting with ex-vivo models or POEM simulators; mechanical and virtual reality (VR) simulators are commonly used during early training. Preclinical training involving ex-vivo and live animal models is suggested to prepare trainees for safe and effective procedures. Studies suggest varying numbers of procedures for training, with approximately 20-40 cases needed before a first plateau is achieved in terms of complications and speed. The duration of on-patient clinical training varies depending on prior experience. Mentorship programs, workshops, and case discussions may facilitate dynamic knowledge transfer. In addition, adverse event management is a crucial aspect of any TSE training program. Existing evidence supports the use of preclinical models and emphasizes the importance of specialized training programs for TSE in alignment with our proposed step-up training approach. This review outlines practical recommendations for the theoretical knowledge and technical skills required before commencing TSE training, covering clinical understanding, diagnostic and outcome assessment, procedural requirements, and the role of mentorship programs.

Effects of Real Time Feedback on Novice's Laparoscopic Learning Curve

OBJECTIVE

Analyze the learning curve of medical students when they are trained with a laparoscopic box trainer and are presented with different modes of real-time feedback on their performance in the laparoscopic suturing procedure.

DESIGN

A prospective randomized controlled trial (RTC) was performed. Three groups were proposed: control, visual, and haptic. The block randomization technique was used to assign the participants to one of the three groups. Each group trained the intracorporeal square flat knot task in a standardized FLS box simulator. A total of 11 sessions were programmed for this study: a pre-training session, eight training sessions, a post-training session, and a follow-up session. Measurement of the generated reaction force during the task were taken weekly for the first 10 sessions (pre-training, training, and post-training); then, the follow-up measurement was taken a month after.

SETTING

This study was carried out in a single center at the Unidad de Simulación de Posgrado (USIP) of the postgraduate medicine program of the Universidad Nacional Autónoma de México (UNAM) between May and August 2023.

PARTICIPANTS

The eligible participants were medical students without experience in minimally invasive surgery. All social service intern medics doing their social service in the USIP were invited to participate. A total of 20 participants entered the study from which 18 of them finished all the programmed sessions.

RESULTS

A total of ten metrics were extracted from the reaction force signal measured at each session. All metrics are directly proportional to the reaction force and low magnitudes imply high tissue-handling proficiency. All groups improved their tissue handling skills, being the visual group the one who achieved better performance, followed by the haptic group and lastly the control group.

CONCLUSION

The use of real time feedback, especially visual feedback can help novices to shorten the learning process of tissue handling and achieve a better proficiency in advanced tasks in shorter training periods.

Comparing clinical outcomes of peroral endoscopic myotomy for achalasia between Eastern and Western countries: a systematic review and meta-analysis

Peroral endoscopic myotomy (POEM) has revolutionized the therapeutic strategy for achalasia with promising results. We conducted this meta-analysis to compare clinical outcomes between Eastern and Western countries. A comprehensive literature search was conducted in PubMed, EMBASE, Web of Science and Cochrane Library databases to query for studies that assessed the efficacy of POEM for achalasia. All articles published from inception to December 31, 2021 were included. The primary outcome was the pooled clinical success rate. The secondary outcomes included the pooled technical success rate, incidence of adverse events, procedure time and hospital stay. Eighteen Eastern studies involving 5962 patients and 11 Western studies involving 1651 patients were included. The pooled clinical success rate and technical success rate for POEM was equal in the Eastern studies compared to Western studies. The pooled incidence of procedure adverse events for POEM was a little lower in the Eastern studies compared to Western studies (6.6% vs. 8.7%). Similarly, the incidence of reflux-related adverse events was lower in Eastern studies than that in Western studies. The pooled procedure time of POEM was shorter in Eastern studies compared to Western studies (61 minutes vs. 80 minutes), while the length of hospital stay was longer in Eastern studies compared to Western studies (5.8 days vs. 2.4 days). Overall, Eastern countries have the similar POEM outcomes compared to Western countries. However, Eastern countries still need to do more to reduce the length of hospital stay.

Peroral endoscopic myotomy compared to laparoscopic Heller myotomy and pneumatic dilation in the treatment of achalasia: a systematic review

Peroral endoscopic myotomy (POEM) is an intervention for the treatment of achalasia which has gained popularity over the last decade. It's efficacy and invasiveness are comparable to laparoscopic Heller myotomy (LHM). The purpose of this systematic review is to compare POEM to existing therapies. The systematic review was performed following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. MEDLINE, EMBASE, Web of Science and Cochrane Libraries were searched using keywords: esophageal achalasia, POEM, LHM, pneumatic dilation (PD), and related terms. The studied outcomes were Eckardt score, clinical success, hospital stay, cost-utility analysis, complications, and post-treatment gastro-esophageal reflux disease. Articles were reviewed by one researcher and uncertainty was resolved by a second researcher. The search strategy retrieved 1948 citations. After removing duplicates and applying the exclusion criteria, 91 studies were selected for full-text review of which a total of 31 studies were considered eligible for further analysis, including two studies which were found through manual searching. POEM has improved efficacy compared to PD with similar cost-effectiveness. POEM results showed comparable patient outcomes when compared with laparoscopic myotomy. Overall, POEM is a feasible first-line treatment for achalasia.

Peroral Endoscopic Myotomy; Novice Surgeon Learning Curve

INTRODUCTION

Peroral endoscopic myotomy (POEM) is a novel endoscopic procedure used to treat achalasia and other spastic esophageal disorders that is an alternative to Heller myotomy. We seek to define the learning curve of POEM for a foregut surgeon with no formal endoscopic or POEM training by analyzing different intraoperative factors in a single series.

METHODS AND PROCEDURES

The first 38 consecutive patients undergoing POEM by a single foregut surgeon were included in this retrospective study. Inverse curve regression models were used to analyze total operative time (TOT) and total operative time per centimeter of myotomy (TOT-CM), in addition to other intraoperative variables. Clinical outcomes were reported as pre- and post-operative Eckardt Scores.

RESULTS

All patients had type II achalasia with no post-operative complications observed. Eckardt scores improved postoperatively (median (range): 1 (0-4)) compared with the preoperative scores (10 (8-12)) (P < .001). The total operative time (median 76 minutes, range 51-129) decreased significantly over the course of the series (R2 = .38, P < .001), with a learning plateau at 70 minutes and a learning rate of 12 cases. Total operative time per centimeter of myotomy (median 7.08 min/cm, range 4.25 to 15.38) decreased over time (R2 = .45, P < .001), with a learning plateau at 7 minutes/cm and a learning rate of 12 cases.

CONCLUSION

The number of cases for a foregut surgeon to become proficient in a POEM procedure was found to be 12-14 cases. The learning curve for a POEM in a formally trained foregut surgeon may be comparable to an endoscopically trained interventionist.

Long versus short peroral endoscopic myotomy for the treatment of achalasia: results of a non-inferiority randomised controlled trial

OBJECTIVE

Peroral endoscopic myotomy (POEM) has become standard treatment for achalasia with comparable efficacy to surgery. In most of published series, the length of myotomy is 12-13 cm. Shorter cuts could have the advantage of shorter procedure time and possibly reduced gastro-oesophageal reflux disease (GORD) rate.

DESIGN

This single-centre, patient-blinded, randomised, non-inferiority clinical trial included 200 patients, who were randomly allocated, to receive either a long-POEM (13 cm; 101 patients) or a short-POEM (8 cm; 99 patients). Primary outcome was defined as an Eckardt symptom score of ≤3 at 24 months after the procedure; a non-inferiority design was chosen with an accepted success range of 6% between the two treatments. Secondary outcomes included operating time, complication rate, postoperative manometry, GORD rate and quality of life.

RESULTS

In the intention-to-treat analysis, clinical success rates were 89.1% in the long-POEM and 98.0% in the short-POEM group, resulting in an absolute between-group difference of -8.9% (90% CI -14.5 to -3.3).Procedure time was significantly reduced in the short-POEM as compared with the long-POEM group (40 vs 50 min, p<0.0001). Severe adverse events occurred in one patient in both groups.No differences were observed in postoperative GORD: acid exposure >6% on pH monitoring study at 6 months was seen in 34.3% (long-POEM) vs 31.1% (short-POEM), while endoscopic oesophagitis was diagnosed in 37.6% vs 51.5% at 6 months and in 21% vs 24.5% at 24 months. Regular proton pump inhibitor use was not different either (36.8% vs 37.5%).

CONCLUSIONS

Our study demonstrates non-inferiority of a shorter cut length of POEM as compared with the standard treatment, which saved some procedural time. GORD rate was not reduced by reducing cutting length.

TRIAL REGISTRATION NUMBER

NCT03450928.

Early outcomes following EndoFLIP-tailored peroral endoscopic myotomy (POEM): the establishment of POEM services in two UK centers

Peroral endoscopic myotomy (POEM) is a safe and effective minimally invasive treatment for achalasia. Postoperative reflux rates remain high. The functional luminal imaging probe (FLIP) allows intraoperative measurement of lower esophageal distensibility during POEM. In theory, this enables a tailoring of myotomies to ensure adequate distensibility while minimizing postoperative reflux risk. Two prospectively collected POEM databases were analyzed from two UK tertiary upper GI centers. The operators in each center used FLIP measurements to ensure adequate myotomy. Outcome measures included Eckardt score (where <3 indicated clinical success) and proton-pump inhibitor use (PPI), collected at the first postoperative appointment. Length of stay was recorded as were complications. In all, 142 patients underwent POEM between 2015 and 2019. Overall, 90% (128/142) had postoperative Eckardt scores of <3 at 6 weeks. Clinical success improved to 93% (66/71) in the latter half of each series with a significantly higher rate of complete symptom resolution (53 versus 26%, P = 0.003). In all, 79% of the poor responders had previous interventions compared with 55% of responders (P = 0.09). Median post-myotomy distensibility index was 4.0 mm2/mmHg in responders and 2.9 in nonresponders (P = 0.16). Myotomy length of <7 cm was associated with 93% clinical success and 40% post op PPI use compared with 60% PPI use with longer myotomies. There were two type IIIa, two type IIIb, and one IV Clavien-Dindo complications. This is the largest series of endoluminal functional lumen imaging probe (EndoFLIP)-tailored POEM in the UK to date. The shorter myotomies, allowed through EndoFLIP tailoring, remained clinically effective at 6 weeks. Complete symptom response rates improved in the latter half of each series. More data will be needed from high-volume collaborations to decipher optimal myotomy profiles based on EndoFLIP parameters.

Learning curve for esophageal peroral endoscopic myotomy: a systematic review and meta-analysis

BACKGROUND AND STUDY AIMS : Peroral endoscopic myotomy (POEM) is a minimally invasive endoscopic procedure for the treatment of achalasia and certain spastic esophageal motility disorders, delivering excellent results in experienced hands. However, this complex and technically challenging procedure requires advanced endoscopic skills. The aim of this study was to conduct a systematic review and meta-analysis of current data to evaluate the learning curve for POEM in new adopters of this technique. METHODS : Electronic databases (PubMed, Embase, and Cochrane Library) from inception to November 2021 were searched for publications addressing the learning curve in POEM. Pooling was conducted by both fixed- and random-effects models. Secondary outcomes reviewed were clinical success defined by Eckardt score ≤ 3 when available and adverse events. RESULTS : Eight studies involving 1904 patients met the inclusion criteria. In the pooled analysis, new adopters of POEM attained proficiency at a mean of 24.67 procedures (95 %CI 23.93 to 25.41). Once proficiency was achieved, the pooled total procedure time plateaued at a mean of 85.38 minutes (95 %CI 81.48 to 89.28), the pooled mean procedure time per centimeter of myotomy was 6.25 minutes (95 %CI 5.69 to 6.82), and the pooled mean length of myotomy was 11.49 cm (95 %CI 10.90 to 12.08). CONCLUSIONS : Our analysis showed that new adopters of POEM with previous advanced endoscopy experience required about 25 procedures to attain proficiency. The average time for each procedure once proficiency was attained was about 85 minutes.

Training in esophageal peroral endoscopic myotomy (POEM) on an ex vivo porcine model: learning curve study and training strategy

BACKGROUND

Peroral endoscopic myotomy (POEM) is a very effective treatment for achalasia. However, training remains non-standardized. We evaluated a training curriculum, including ex vivo cases, followed by patients' cases under expert supervision. The objective was to establish a learning curve of POEM.

MATERIALS AND METHODS

Four operators having completed advanced endoscopy fellowship were involved. They had already observed > 30 cases performed by experts. They performed 30 POEMs standardized (tunnel and myotomy lengths) procedures on ex vivo porcine model. Procedural times, number/volume of injections, mucosal and serous perforations, and myotomy length were collected. The learning curve was assessed using dissection speed (DS) and a dedicated performance score (PS), including learning rate (LR) and learning plateau (LP).

RESULTS

The operators completed all cases within 4 months (median of 3.5 cases/week). The mean procedural time was 43.3 min ± 14.4. Mean myotomy length was 70.0 mm ± 15.6 mm. Dissection speed averaged 1.78 mm/min ± 0.78. Using DS and PS as parameter, the LR was reached after 12.2 cases (DS = 2.0 mm/min) and 10.4 cases, respectively. When comparing the LP and the plateau phase, the DS was slower (1.3 ± 0.5 mm/min versus 2.1 ± 0.54 mm/min, p < 0.005) and perforations were decreased: 0.35 ± 0.82 in LP vs. 0.16 ± 0.44 in PP. Following this training, all operators performed 10 supervised cases and are competent in POEM.

CONCLUSION

The association of observed cases and supervised ex vivo model training is effective for starting POEM on patients. The learning curve is 12 cases to reach a plateau.

Learning curve for peroral endoscopic myotomy in therapeutic endoscopy experts and nonexperts: Large single-center experience

OBJECTIVES

Reports on learning curve for peroral endoscopic myotomy (POEM) in therapeutic endoscopy nonexperts are limited. We aimed to assess the number of cases required to achieve POEM proficiency for endoscopic submucosal dissection (ESD) experts and nonexperts.

METHODS

This is a retrospective study at the largest POEM referral center in Japan. POEM between April 2014 and December 2020 were included. Nonexperts and ESD experts were divided by training phases: A, 1-20; B, 21-40; C, 41-60; D, 61-80; and E, 81-100 cases. Primary outcome was operation time, and the phase to reach target time (83 min) was investigated. Secondary outcomes were clinical success rate, adverse events, and post-POEM gastroesophageal reflux disease (GERD).

RESULTS

Five hundred and sixty-six cases were performed by 14 nonexperts, and 555 cases by 15 ESD experts. As the primary outcome, operation time in nonexperts was: A, 95 (79-115.8); B, 86.5 (71-105); C, 80 (70-100); D, 73 (64.5-100.5); and E, 73.5 (57.8-88.8) min, while in ESD experts: A, 90 (74-128); B, 77 (70-92); and C, 77 (70-93.5) min (median [interquartile range]). Operation time decreased significantly as experience increased in both groups (P < 0.001), and nonexperts required 41-60 cases to achieve proficiency, while experts required 21-40 cases. As secondary outcomes, in nonexperts, clinical success was 96.9-100%, adverse events were 5.0-9.2%, symptomatic GERD was 11.8-26.5%, and proton pump inhibitor (PPI) intake was 11.5-18.7% in each phase. While in experts, clinical success was 96.2-100%, adverse events were 3.0-5.8%, symptomatic GERD was 14.6-22.0%, and PPI intake was 12.6-17.9%. There were no significant differences among training phases.

CONCLUSIONS

Non-ESD experts require more cases to achieve proficiency in POEM. These results are useful for establishing POEM training programs and institutional implementation of the procedure.

Successful Design and Implementation of a POEM Program for Achalasia in an Integrated Healthcare System

BACKGROUND

Per Oral Endoscopic Myotomy (POEM) is a minimally invasive treatment for achalasia with results comparable to laparoscopic Heller myotomy (LHM). Studies have described the development of proficiency for endoscopists learning to perform POEM, and societies have defined educational and technical objectives for advanced endoscopy fellows in training. However, there is limited guidance on the organizational strategy and educational plan necessary to develop an achalasia service with POEM expertise.

AIMS

We aim to outline the steps for design and implementation of a successful POEM program.

METHODS

We reported our experience developing a multi-disciplinary clinical program for POEM and the steps taken to achieve procedural proficiency. We also reported our technical success (successful tunneling into the gastric cardia and myotomy of LES muscle fibers) and clinical success (post-procedure Eckardt score ≤ 3) at 3-6 months and 12 months post-procedure. Adverse events were classified per the ASGE lexicon for endoscopic adverse events.

RESULTS

After creating a multi-disciplinary clinical program for achalasia and completing procedural proficiency for POEM, our technical success rate was 100% and clinical success rate 90% for the first 41 patients. One adverse event (2.4%) occurred, moderate in severity per the American Society of Gastrointestinal Endoscopy (ASGE) lexicon for adverse endoscopic events.

CONCLUSION

In this study, we outlined the steps involved to establish a POEM service in a large integrated healthcare system. Prior competency in interventional endoscopy, procedural training models, POEM observation and education, proctorship, and interdisciplinary patient care are recommended.

Peroral endoscopic myotomy: is it better to perform it in naive patients or as second-line therapy? Results of an open-label-controlled study in 105 patients

BACKGROUND

Whether Peroral Endoscopic Myotomy (POEM) can be proposed as a second-line treatment in patients with achalasia remains to be confirmed in real-life series.

OBJECTIVE

This study aimed to compare the efficacy, feasibility and safety of POEM between treatment-naïve patients and patients who had prior endoscopic or surgical therapies for achalasia.

METHODS

All consecutive patients who underwent a POEM procedure for achalasia in our centre from June 2015 to September 2018 were included in this retrospective study. They were classified into treatment-naïve patients (POEM1) and patients who had at least one previous endoscopic and/or surgical treatment for achalasia (POEM2).

RESULTS

A total of 105 patients were included, 52 in the POEM1 group and 53 in the POEM2 group. Clinical success (defined as an Eckardt score ≤ 3) at 6 months was observed in 93% of POEM1 patients and 84% of POEM2 patients (p = 0.18). Technical success rate was not significantly different between the two groups (100% vs 96%, respectively; p = 0.50). No significant difference was noted in terms of adverse event rate (19% vs 19%, respectively; p = 1.00). Post-procedure pain occurred in 12% of treatment-naive and 9% of non-naïve patients (p = 0.76). The median length of hospital stay was 3 days in both groups (p = 0.17). Symptomatic gastroesophageal reflux occurred in 25% of POEM1 patients and 16% of POEM2 patients (p = 0.24).

CONCLUSION

Efficacy, feasibility and safety of POEM are not different between treatment-naïve and non-naïve patients. POEM is a valuable second-line approach in patients with persistent symptoms of achalasia after surgical or endoscopic treatments.

Per Oral Endoscopic Myotomy (POEM) for pediatric achalasia: Institutional experience and outcomes

BACKGROUND

The surgical treatment of achalasia by both laparoscopic and endoscopic approaches has been recognized as the definitive management in children. Despite reported low volumes in many centers, there has been an increasing worldwide experience with endoscopic approaches to pediatric achalasia. The aim of this study is to report our institutional experience with per oral endoscopic myotomy (POEM) as first-line or revisional therapy for achalasia.

METHODS

An IRB approved retrospective review of all patients who underwent operative procedures for achalasia, specifically with the POEM technique, from July 2015 to September 2021. Data including demographics, intra-operative details, pre and post operative Eckardt scores, complications, outcomes, and follow-up were obtained.

RESULTS

During the study period, a total of 43 children underwent 46 operations for achalasia including POEM and laparoscopic Heller myotomy (LHM). Operations included 37 POEMS (33 primary POEMS; 3 POEMS after failed LHM; and 1 POEM after failed POEM). Additionally, 9 LHM operations including, 4 primary LHM; 3 attempted POEMS converted to LHM; 1 attempted POEM after failed LHM converted to redo LHM; and 1 LHM after failed POEM. In the POEM group (n = 37), based on the high resolution esophageal manometry findings Chicago Classification types at diagnosis were as follows: 9 patients were type I (24.3%); 25 patients were type II (67.6%); 2 patients were type III (5.9%) and 1 patient was unknown type (2.7%). Sixteen children (43.2%) had prior endoscopic treatment of achalasia prior to POEM [Pneumatic Balloon Dilatation (PBD), and/or Botox injection (BTI)],), while prior operative intervention occurred in 4 patients (10.8%), 3 LHM and 1 POEM. Age at operation was 2-18 years (mean ± SD age: 11.6 ± 4.5 years). Weight at operation 11.8-100.7 kg (mean ± SD kg; 39 ± 19.9 kg). Range of baseline Eckardt score was 4-10 (mean ± SD: 6.73 ± 1.5). Operative time was 64-359 min (mean ± SD minutes: 138.1 ± 62.2 min). Intraoperative complications occurred in 16 patients (43.2%) but did not require reoperation during index admission including: 4 mucosotomy (11.8%); 9 pneumothoraces (24.3%); 2 pneumomediastinum (5.4%); 10 pneumoperitoneum (27%); 0 sub-mucosal tunnel bleeding (0%); 0 open conversion/death (0%). Post operative complications included: 5 recurrent dysphagia (13.5%); 0 esophageal leak (0%); 3 GERD (8.1%); 1 failed POEM (2.7%). Median length of stay was 2 days (mean ± SD days: 2.4 ± 0.9 day). Follow-up ranged from 1 to 74 months (median 15 months), mean follow-up 22.6 months ± 20 months. Post POEM Eckardt score was 0.6 ± 0.9. Five patients required a single PBD post POEM (13.5%) and 1 patient required a repeat myotomy (LHM) after POEM (2.7%) for a 16.2% reintervention rate. Subsequent normalization of Eckardt scores (≤ 3) and symptomatic relief was achieved in all patients (100%).

CONCLUSIONS

POEM as first-line therapy for pediatric achalasia, or as a secondary procedure after failed prior myotomy or POEM, in our experience is safe and effective. We have shown equivalent results to our own prior experience with LHM. Long-term follow-up will be performed to monitor for recurrent symptoms, adequate physical growth, and general development.

LEVEL OF EVIDENCE

II.

New Applications for Submucosal Tunneling in Third Space Endoscopy: A Comprehensive Review

Third space endoscopy (TSE), a type of natural orifice transluminal endoscopic surgery, was first introduced a decade ago, and since then, has revolutionized the field of therapeutic endoscopy. TSE involves tunneling into the submucosal space between the intestinal mucosa and the muscularis propria. By accessing this "third space," endoscopists can perform minimally invasive myotomies, resections, and dissections while maintaining the mucosa and preventing full-thickness perforation. TSE procedures can be used to treat motility disorders as well as neoplasms throughout the gastrointestinal tract, which were traditionally conditions that would require open or laparoscopic surgery. The main TSE procedures include peroral endoscopic myotomy, gastric peroral endoscopic myotomy, Zenker peroral endoscopic myotomy, submucosal tunneling for endoscopic resection, endoscopic submucosal tunnel dissection, peroral endoscopic tunneling for restoration of the esophagus, and per-rectal endoscopic myotomy. Some of those procedures have now been accepted as viable alternative to surgical techniques due to their limited invasiveness, safety and cost. This review will explore the different techniques recently added to our arsenal while describing their potential efficacy and limitations.

Gastric Peroral Endoscopic Myotomy: A Specific Learning Curve

INTRODUCTION

Gastric peroral endoscopic pyloromyotomy (G-POEM) is a novel option for patients with gastroparesis. It involves submucosal tunneling across the pylorus, followed by pyloromyotomy, and subsequent closure of the endoscopic tunnel. The aim of this study was to determine the learning curve for G-POEM.

METHODS

Consecutive patients undergoing G-POEM by a single operator were included from a prospective registry over 2 years. Demographics, procedure info, postprocedure follow-up data, and adverse events were collected. Nonlinear regression and cumulative sum control chart analyses were conducted for the learning curve. Clinical outcomes were improvement in Gastroparesis Cardinal Symptom Index score and gastric emptying scintigraphy.

RESULTS

Thirty-six patients were included (16.7% M, mean age 46 y). The majority had idiopathic gastroparesis (n=16, 44%), with the remaining having diabetes (n=5, 17%), postsurgical (n=10, 28%), or other (n=4, 11%). Technical success was achieved in 35 of 36 (97%). There was a significant reduction in the total Gastroparesis Cardinal Symptom Index score (2.09 units, P<0.00001) and a significant reduction in postoperative gastric emptying scintigraphy (82.44 mins, P<0.00001). Mean follow-up was 15 months (SD, 1.05). Median procedure time was 60.5 minutes (range, 35 to 136). Cumulative sum control chart shows 60-minute procedure was achieved at the 18th procedure. Procedure durations further reduced with consequent procedures with the last 3 being 45 minutes, thus demonstrating continued improvement with ongoing experience (nonlinear regression P<0.0001).

CONCLUSION

Endoscopists experienced in G-POEM are expected to achieve a reduction in procedure time over successive cases, with efficiency reached at 60.5 minutes and a learning rate of 18 cases with continuing improvement.

Per-oral Endoscopic Myotomy: State of the Art

For more than a decade, per-oral endoscopic myotomy (POEM) has been performed for the treatment of achalasia and other dysmotilities of the esophagus. POEM has become an accepted alternative to Heller myotomy, a salvation technique for patients not responding to Heller myotomy and the favorite intervention for diffuse esophageal spasm and jackhammer esophagus. POEM paved the way for endoscopic pyloromyotomy, Zenker's diverticulum myotomy, and submucosal tunneling with endoscopic resection. This review will cover the technique and the most current literature of this revolutionary third space technique.

Pilot prospective study on formal training in per-oral endoscopic myotomy (POEM) during advanced endoscopy fellowship

Background and study aims  Gastroenterology societies have recently proposed core curricula for training in per-oral endoscopic myotomy (POEM) based on expert opinion with limited data on its applicability for advanced endoscopy fellowship (AEF) trainees. We prospectively evaluated the feasibility of a structured POEM training curriculum during a dedicated AEF and the trainee's performance during independent practice. Methods  This was a single-center prospective study evaluating a trainee's performance of POEM using a structured assessment tool (POEMAT) to assess core cognitive and technical skills. The trainee's performance was then prospectively assessed during the first 12 months of independent practice. Results  The trainee, who had not prior background in submucosal endoscopy, first observed 22 POEM cases followed by 35 hands-on procedures during his advanced endoscopy fellowship. Based on the POEMAT, submucosal entry and mucosal incision closure were the most challenging technical aspects, while cognitive skills were uniformly attained early in training. Overall, the trainee was able to cross the threshold for competence in his POEMAT performance score in 15 of his last 18 cases (83.3 %). The trainee performed 16 POEMs (baseline mean Eckardt 7.2) in his first 12 months of independent practice. Mean procedural time was 79.8 minutes (interquartile range: 67-94 minutes minutes) with no adverse events. Clinical success (Eckardt score < 3) was achieved in 100 % of the cases at a median follow-up of 20 weeks. Conclusions  Results from this pilot study support the adoptability of the recently proposed core curricula for POEM training within the context of a dedicated AEF and provide a potential blueprint for future studies of performance in POEM among trainees.

The learning curve for transoral incisionless fundoplication

Background and study aims  Transoral incisionless fundoplication (TIF) is a safe and effective minimally invasive endoscopic technique for treating gastroesophageal reflux disease (GERD). The learning curve for this technique has not been reported. We studied the learning curve for TIF when performed by a gastroenterologist by identifying the threshold number of procedures needed to achieve consistent technical success or proficiency (consistent creation of TIF valve ≥ 270 degrees in circumference, ≥ 2 cm long) and efficiency after didactic, hands-on and case observation experience. Patients and methods  We analyzed prospectively collected data from patients who had TIF performed by a single therapeutic endoscopist within 17 months after basic training. We determined thresholds for procedural learning using cumulative sum of means (CUSUM) analysis to detect changes in achievement rates over time. We used breakpoint analysis to calculate procedure metrics related to proficiency and efficiency. Results  A total of 69 patients had 72 TIFs. The most common indications were refractory GERD (44.7 %) and proton pump inhbitor intolerance (23.6 %). Proficiency was achieved at the 18 ^th to 20 ^th procedure. The maximum efficiency for performing a plication was achieved after the 26 ^th procedure, when mean time per plication decreased to 2.7 from 5.1 minutes (P < 0.0001). TIF procedures time varied until the 44 ^th procedure, after which it decreased significantly from 53.7 minutes to 39.4 minutes (P < 0.0001). Conclusions  TIF can be safely, successfully, and efficiently performed in the endoscopy suite by a therapeutic endoscopist. The TIF learning curve is steep but proficiency can be achieved after a basic training experience and 18 to 20 independently performed procedures.

The Learning Curve for Peroral Endoscopic Myotomy in Latin America: A Slide to the Right?

BACKGROUND/AIMS

Peroral endoscopic myotomy (POEM) has been increasingly used for achalasia in Latin America, where Chagas disease is prevalent, and this makes POEM more challenging. The aim of this study was to determine the learning curve for POEM in Latin America.

METHODS

Patients undergoing POEM in Latin America with a single operator were included from a prospective registry over 4 years. Non-linear regression and cumulative sum control chart (CUSUM) analyses were conducted for the learning curve.

RESULTS

A total of 125 patients were included (52% male; mean age, 59 years), of which 80 had type II achalasia (64%), and 38 had Chagas disease (30%). The average pre-procedure and post-procedure Eckardt scores were 6.79 and 1.87, respectively. Technical success was achieved in 93.5% of patients, and clinical success was achieved in 88.8%. Adverse events occurred in 27 patients (22%) and included bleeding (4 patients), pneumothorax (4 patients), mucosal perforation (13 patients), mediastinitis (2 patients), and leakage (4 patients).
The CUSUM chart showed a median procedure time of 97 min (range, 45-196 min), which was achieved at the 61st procedure. Procedure duration progressively decreased, with the last 10 procedures under 50 min approaching a plateau (p-value <0.01).

CONCLUSION

Mastering POEM in Latin America requires approximately 61 procedures for both POEM efficiency and to accomplish the procedure within 97 minutes.

Assessment of the learning curve for EUS-guided gastroenterostomy for a single operator

BACKGROUND AND AIMS

EUS-guided gastroenterostomy (EUS-GE) is increasingly used as an alternative to surgery and enteral stent placement to manage gastric outlet obstruction (GOO). However, no data are available on the learning curve (LC) for EUS-GE. Defining the LC is necessary to create adequate subspecialty training programs and quality assurance.

METHODS

This study is a retrospective analysis of a prospectively maintained dataset of patients who underwent EUS-GE at 1 tertiary referral center. Primary outcome was the LC for EUS-GE defined by the number of cases needed to achieve proficiency and mastery using cumulative sum (CUSUM) analysis. Moving average graphs and sequential time-block analysis were also performed to assess procedural time. Secondary outcomes included efficacy and safety of EUS-GE.

RESULTS

Eighty-seven consecutive patients underwent EUS-GE, mostly for malignant GOO. For consistency, 14 patients were excluded from analysis (noncautery-assisted EUS-GE, 11; surgical anatomy, 3). The same endoscopist performed all procedures using the same freehand technique. Technical success was achieved in 68 of 73 patients (93%). Immediate adverse events occurred in 4 patients (5.5%), whereas late adverse events occurred only in 1 patient (1%), all managed conservatively or endoscopically. All immediate adverse events occurred during the first 39 cases. Clinical success (defined as resuming at least an oral liquid diet within a week) was achieved in 97% of patients. The mean procedural time was 36 minutes (standard deviation, 24). Evaluation of the CUSUM curve revealed that 25 cases were needed to achieve proficiency and 40 cases to achieve mastery. These results were confirmed with the average moving curve and sequential time-block analysis.

CONCLUSIONS

We report, for the first time, data on the LC for EUS-GE. About 25 procedures can be considered as the threshold to achieve proficiency and about 40 cases are needed to reach mastery of the technique.

Impact of Focused Hands-on Training Course on Practice Adoption of Advanced Endoscopic Techniques and Per-Oral Endoscopic Myotomy

Background: Per-oral endoscopic myotomy (POEM) is a valuable tool for the treatment of foregut motility disorders. Hands-on courses are often utilized at the initial means of training in POEM. Whether such training is sufficient to allow individuals to launch an independent practice in POEM is unknown. The purpose of this study was to evaluate the successes and barriers of implementing a POEM practice after attending a hands-on course. Methods: We evaluated participants of a 2-day focused POEM training course. All participants of the course were sent a survey to assess their endoscopic practice before and after the course, concentrating on their ability to implement POEM after returning to their home institution. Results: Between 2012 and 2017, 11 POEM courses were held at our institution, with a total of 102 trainees. Fifty-five individuals responded to our survey (53.9%), most of whom were general surgeons who were already doing some therapeutic endoscopy but had not previously performed POEM. More than half (58.2%) were able to institute a POEM practice at their home institution after the course. Those that were successful in starting a POEM practice were more often those with previous advanced endoscopic experience (90.3%). Success was assisted by high rates of additional explant laboratories (43.6%) and in-person proctoring (52.4%) after completing the course. Those that did not start a POEM practice sited lack of institutional support as the main barrier, followed by problems with insurance approval, and lack of referral volume. Conclusion: Despite the complexity of the POEM procedure, a focused hands-on POEM training course is associated with a high rate of implementation of an independent POEM practice, particularly in individuals with previous advanced endoscopic experience. The largest barriers to POEM adoption are not technical factors, but rather are related to institutional and insurance factors.

The Modern Age of POEM: the Past, Present and Future of Per-Oral Endoscopic Myotomy

BACKGROUND

Per-oral endoscopic myotomy (POEM) has gained widespread enthusiasm amongst foregut specialists since its introduction in the mid 2000s as an effective and less invasive treatment option for achalasia. As more than 6000 POEM procedures have been performed to date throughout the world, we aim to summarize the history and current state of POEM in the treatment of esophageal motility disorders.

METHODS

We performed a comprehensive review of the published literature focusing on the history and development of the POEM procedure, and its most current applications and outcomes.

RESULTS

Multiple favorable long-term studies have been published advocating for the use of POEM as a valid and perhaps the most valid treatment option for achalasia. The procedure is also increasingly being applied to a wider spectrum of esophageal motility disorders including type III achalasia, spastic esophageal disease or isolated lower esophageal sphincter (LES) dysfunction, as well as new endoluminal procedures such as submucosal tumor endoscopic resection (STER), endoscopic fundoplications (POEM-F) and peroral pyloromyotomy (POP or G-POEM).

CONCLUSIONS

While POEM is a proved and valid procedure, its further adoption is being threatened by external factors: challenges related to teaching, institutional support (politics) and insurance reimbursement. While this technique has come an incredible distance in its relatively short lifespan, the future of POEM in the USA will depend on the support from surgical societies to validate it as a valuable tool in the esophageal specialist's armamentarium, and to encourage a commitment to training in endoluminal surgery.

Recent advances in third space or intramural endoscopy

Third space endoscopy or intramural endoscopy is based on the principle that the deeper layers of the gastrointestinal tract can be accessed by tunneling in the submucosal space and maintaining the integrity of the overlying mucosa. The era of third space endoscopy started with peroral endoscopic myotomy (POEM) for treatment of achalasia and has expanded to treat various other gastrointestinal disorders. The technique is also currently used for treatment of refractory gastroparesis, Zenker’s diverticulum (ZD), resection of subepithelial tumors and early cancers of the gastrointestinal tract and Hirschsprung’s disease (HD). These procedures are rapidly emerging as minimally invasive alternatives to conventional surgery. They are safe and effective with excellent outcomes. This review focuses on the evolution and current applications of third space endoscopy in various gastrointestinal disorders. Key points: (1) Third space or intramural endoscopy initially started with the POEM procedure for treatment of achalasia; (2) Advancements in procedural techniques have expanded its application to treat other gastrointestinal disorders such as refractory gastroparesis, ZD, HD, resection of subepithelial tumors and early gastrointestinal cancers; (3) These procedures are highly effective with excellent outcomes and low complication rates; and (4) Third space endoscopic procedures are rapidly emerging as minimally invasive alternatives to conventional surgery.

Per-oral endoscopic myotomy (POEM) training and skills evaluation tool: a pilot study

Background and study aims  Hands-on training for per-oral endoscopic myotomy (POEM) in the United States is limited and without a structured curriculum or assessment tool. Training to competency in POEM is critical and POEM trainees must acquire multiple cognitive and technical skills to achieve proficiency. The aim of this study was to develop a POEM training and skills evaluation tool. Patients and methods  The training protocol included initial explant porcine models followed by live human cases, proctored by a single endoscopist experienced in POEM who prospectively graded trainees for each step ("skill") of the procedure on a 5-point scale. Procedural skills were divided into cognitive and technical skills. Acceptable passing level was considered a score ≥ 4 for each skill. Results  Three trainees completed a total of 18 cases (8 cases on animal explant models and 10 human cases). Overall, cognitive skills were acquired early in training with scores of ≥ 4 achieved by ≤ 3 cases. Technical skills required more cases and direction with scores ≥ 4 in technical skills achieved by three porcine and eight human cases. Entry of the endoscope into the submucosal space and submucosal tunneling were the most challenging steps followed by myotomy. Conclusion  This pilot study introduces a POEM training and skills evaluation tool for training to competency. Submucosal entry, tunneling, and myotomy were the most challenging to learn while cognitive skills were learned early in training. Evaluation of more trainees at multiple sites will be necessary to further validate the utility of this tool.

Implementation of a peroral endoscopic myotomy program

INTRODUCTION

the aim of our study was to develop a peroral endoscopic myotomy (POEM) program in our Unit following a two-step sequence: training on animal models and supervision by an experienced endoscopist during the first human cases.

METHODS

a single endoscopist experienced in advanced endoscopy was trained in POEM. After observing POEM in referral centers, training was implemented on swine models (preclinical phase). Technical aspects and adverse events were prospectively recorded. A first subset of cases (group A) was compared to a second one (group B) to assess our progression. Finally, POEM was implemented in humans under the supervision of an experienced endoscopist (clinical phase). The outcomes and adverse events were prospectively recorded.

RESULTS

during the preclinical phase, 15 POEM procedures were performed on live pigs. Severe adverse events (AE) were less frequent in group B than in group A (12 % vs 57 %, p = 0.07). After nine cases, a plateau of adverse events was reached. During the clinical phase, eleven POEM procedures were performed in patients under expert supervision. Technical and clinical (Eckardt score ≤ 3) success were 100 % and 91 %, respectively (follow-up 3-21 months). In two cases, intervention of an experienced endoscopist was required (cases 2 and 3) because of a difficult orientation at the esophagogastric junction. One mild pneumoperitoneum occurred, with no severe adverse events reported.

CONCLUSIONS

training in animal models and supervision by an experienced endoscopist during the first cases could provide the necessary skills to perform POEM safely and effectively.

The status of training in new technologies in advanced endoscopy: from defining competence to credentialing and privileging

The landscape of advanced endoscopy continues to evolve as new technologies and techniques become available. Although postgraduate advanced endoscopy fellowships have traditionally centered on ERCP and diagnostic EUS, the breadth of training has increased over the years in response to the ever-growing demand for therapeutic endoscopy. The increasing diversity and complexity of emerging endoscopic techniques accompanied by the shift in focus toward competency-based medical education requires innovative changes to the curriculum that will ensure adequate training yet without compromising best patient practices. The purpose of this review is to highlight the expansive array of advanced endoscopic procedures and the challenges of both defining and measuring competence during training. All authors are interventional endoscopists at their respective institutions performing these complex procedures, as well as training fellows in these techniques. We share our perspectives based on our experience navigating through these issues at our institutions and discuss strategies to standardize training and how to potentially incorporate these measures in the process of credentialing and privileging in endoscopy.

Techniques and devices for the endoscopic treatment of gastroparesis (with video)

BACKGROUND AND AIMS

Gastroparesis is a symptomatic chronic disorder of the stomach characterized by delayed gastric emptying in the absence of mechanical obstruction. Several endoscopic treatment modalities have been described that aim to improve gastric emptying and/or symptoms associated with gastroparesis refractory to dietary and pharmacologic management.

METHODS

In this report we review devices and techniques for endoscopic treatment of gastroparesis, the evidence regarding their efficacy and safety, and the financial considerations for their use.

RESULTS

Endoscopic modalities for treatment of gastroparesis can be broadly categorized into pyloric, nonpyloric, and nutritional therapies. Pyloric therapies such as botulinum toxin injection, stent placement, pyloroplasty, and pyloromyotomy specifically focus on pylorospasm as a therapeutic target. These interventions aim to reduce the pressure gradient across the pyloric sphincter, with a resultant improvement in gastric emptying. Nonpyloric therapies, such as venting gastrostomy and gastric electrical stimulation, are intended to improve symptoms. Nutritional therapies, such as feeding tube placement, aim to provide nutritional support.

CONCLUSIONS

Several endoscopic interventions have shown utility in improving the quality of life and symptoms of select patients with refractory gastroparesis. Methods to identify which patients are best suited for a specific treatment are not well established. Endoscopic pyloromyotomy is a relatively recent development that may prove to be the preferred pyloric-directed intervention, although additional and longer-term outcomes are needed.

Third Space Endoscopy: Lessons Learnt From a Decade of Submucosal Endoscopy

The field of third space endoscopy (TSE), also called submucosal endoscopy using a mucosal flap valve, allows secure access to the submucosal and deeper layers of the gastrointestinal tract without the risk of a full-thickness perforation. Since the first description of per-oral endoscopic myotomy (POEM) for the treatment of achalasia cardia 10 years ago, this field has expanded rapidly. Several new procedures, submucosal tunneling endoscopic resection, gastric-POEM, Zenker POEM, per-rectal endoscopic myotomy, diverticular POEM, and recanalization for complete esophageal obstruction (per-oral endoscopic tunneling for restoration of the esophagus), have been performed. All TSE procedures employ a similar technique-after a mucosal incision, a submucosal tunnel is created, a myotomy is performed, or a subepithelial tumor is resected distal to the site of mucosal incision, after which the mucosal incision is closed. Potential indications for TSE include resection of subepithelial tumors in the esophagus, gastroesophageal junction, or stomach; refractory gastroparesis; Zenker diverticulum; Hirschsprung disease or other forms of megacolon; and recanalization for complete esophageal obstruction. Data are currently available for POEM, submucosal tunneling endoscopic resection, and gastric-POEM, although mainly in the form of retrospective studies, and randomized trials and long-term follow-up data are limited. Submucosal endoscopy has an excellent safety profile with very few intraoperative adverse events, the majority being related to insufflation, although bleeding, perforation, and sepsis have been reported. TSE procedures require special training and have demonstrated a learning curve.

The Mexican consensus on non-cardiac chest pain

INTRODUCTION

Non-cardiac chest pain is defined as a clinical syndrome characterized by retrosternal pain similar to that of angina pectoris, but of non-cardiac origin and produced by esophageal, musculoskeletal, pulmonary, or psychiatric diseases.

AIM

To present a consensus review based on evidence regarding the definition, epidemiology, pathophysiology, and diagnosis of non-cardiac chest pain, as well as the therapeutic options for those patients.

METHODS

Three general coordinators carried out a literature review of all articles published in English and Spanish on the theme and formulated 38 initial statements, dividing them into 3 main categories: (i)definitions, epidemiology, and pathophysiology; (ii)diagnosis, and (iii)treatment. The statements underwent 3rounds of voting, utilizing the Delphi system. The final statements were those that reached >75% agreement, and they were rated utilizing the GRADE system.

RESULTS AND CONCLUSIONS

The final consensus included 29 statements. All patients presenting with chest pain should initially be evaluated by a cardiologist. The most common cause of non-cardiac chest pain is gastroesophageal reflux disease. If there are no alarm symptoms, the initial approach should be a therapeutic trial with a proton pump inhibitor for 2-4weeks. If dysphagia or alarm symptoms are present, endoscopy is recommended. High-resolution manometry is the best method for ruling out spastic motor disorders and achalasia and pH monitoring aids in demonstrating abnormal esophageal acid exposure. Treatment should be directed at the pathophysiologic mechanism. It can include proton pump inhibitors, neuromodulators and/or smooth muscle relaxants, psychologic intervention and/or cognitive therapy, and occasionally surgery or endoscopic therapy.

Peroral Endoscopic Myotomy with the Stag Beetle Knife (SB Knife): Feasibility and Follow-Up

BACKGROUND Recently, a stag beetle (SB) knife was introduced to reduce the difficulty of peroral endoscopic myotomy (POEM). The objective of this study was to evaluate the efficacy and safety of the SB knife. MATERIAL AND METHODS A total of 71 patients undergoing POEM with the SB knife for esophageal achalasia were included. We used esophagography, manometry, esophagogastroduodenoscopy (EGD), and Eckardt score to assess the utility and safety. RESULTS All cases were completed for POEM. The incidence of adverse events during the operation were 2.8%; however, all cases were treated conservatively. There was a vast improvement in clinical symptoms and endoscopic findings. The average Eckardt score was 6.9 before and 0.6 at 1 year after POEM (p<0.05). The average lower esophageal sphincter (LES) pressure before and 6 months after POEM were 44.34±14.83 mmHg and 19.14±6.74 mmHg (p<0.05), respectively. The average LES relaxation pressure before and 6 months after POEM was 12.11±5.02 mmHg and 3.22±2.29 mmHg (p<0.05), respectively. CONCLUSIONS POEM with the SB Knife is technically efficient and safe in treating achalasia and is associated with favorable short-term outcomes.

Peroral Endoscopic Myotomy for Achalasia

Peroral endoscopic myotomy surgery is an incisionless, minimally invasive, natural orifice technique used to treat the symptoms of achalasia and other spastic disorders of the esophagus. Recent experience demonstrates that it can be performed safely by experienced esophageal surgeons and there are very good short-term outcomes comparable to laparoscopic myotomy. The rapid worldwide adoption of this technique demonstrates its potential to replace the current therapies available for achalasia. A cautionary note is important in that long-term outcomes are not yet available in terms of dysphagia and GERD symptoms.

Clinical practice guidelines for peroral endoscopic myotomy

Peroral endoscopic myotomy (POEM) is a novel clinical technique developed in Japan 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 Gastroenterological 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 a few retrospective studies with a small number of participants and short trial periods; hence, the strength of the evidence and 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.

Comprehensive Evaluation of the Learning Curve for Peroral Endoscopic Myotomy

BACKGROUND & AIMS

Peroral endoscopic myotomy (POEM) is a minimally invasive endoscopic surgical procedure that is effective in treatment for spastic esophageal motility disorders. However, little is known about the learning curve for endoscopists. We aimed to evaluate the effects of various factors on the POEM learning curve.

METHODS

We performed a retrospective study of 1346 patients who underwent POEM for achalasia at Shanghai Zhongshan Hospital in China from August 2010 through July 2015. We used risk-adjusted cumulative sum and moving average methods to evaluate outcomes. The primary outcome was a composite of technical failure and adverse events. Secondary outcomes included procedure time and the composite outcome of technical failure, adverse events, and clinical failure of the first 192 cases performed by only the original, training surgeon.

RESULTS

The primary composite outcome occurred in 54 (4%) of the 1346 patients: 10 technical failures and 44 adverse events. This composite outcome was independently associated with the case number (P = .010), full-thickness myotomy (P = .002), and procedure time (P = .001). After we adjusted for these risk factors, cumulative sum analysis showed that the primary composite outcome decreased gradually after 100 cases. The procedure time was high during the first few cases and decreased after endoscopists performed 70 cases. The secondary composite outcome of technical failure, adverse events, and clinical failure for the 192 cases performed by only the original surgeon gradually decreased after 90-100 cases.

CONCLUSIONS

In a retrospective analysis of POEM procedures, we found that 100 cases were required to decrease the risk of technical failure, adverse events, and clinical failure (the learning curve). Seventy cases can be considered the threshold for decreasing procedure time.

Initial experience with peroral endoscopic myotomy for treatment of achalasia in children

BACKGROUND

Achalasia is a primary esophageal motility disorder characterized by aperistalsis of the esophagus and failed relaxation of the lower esophageal sphincter that presents rarely in childhood. The peroral endoscopic myotomy (POEM) procedure is an emerging treatment for achalasia in adults that has recently been introduced into pediatric surgical practice.

METHODS

This is a prospective case series of all children referred to Stanford University Lucile Packard Children's Hospital with manometry-confirmed achalasia who underwent a POEM procedure from 2014 to 2016.

RESULTS

We enrolled 10 subjects ranging in age from 7 to 17years (M=13.4). The mean pre- and 1-month post-procedure Eckardt scores were 7 (SD=2.5) and 2.4 (SD=2) (p<0.001), respectively. The median procedure time for the entire cohort was 142min (range 60-259min) with ongoing improvement with increased experience (R²=0.6, p=0.008). There were no major adverse events.

CONCLUSION

The POEM procedure can be successfully completed in children for the treatment of achalasia with demonstrated short-term post-operative improvement in symptoms. The adoption of advanced endoscopic techniques by pediatric surgeons may enable development of unique intraluminal approaches to congenital anomalies and other childhood diseases.

LEVEL OF EVIDENCE

Treatment Study - Level IV.

A method to improve the accuracy between the presumed depth of excision and the actual depth of excision in women receiving LLETZ cervical treatment; a single-center, two-operator experience

BACKGROUND

We aimed to determine whether continuous auditing of the presumed depth of excision and comparing with the actual depth of excision in women having large loop excision of the transformation zone (LLETZ) improves the ability to acquire the desired depth of excision.

METHODS

This was a prospective study of women submitted to a single LLETZ treatment between 2017-2018. Two senior colposcopists recorded what they presumed was the depth of excision at the time of treatment and the subsequent histopathology report provided the actual excised depth. Multiple linear regression identified independently associated parameters with the difference between presumed and actual excision depth. Non-linear regression determined the learning plateau defined as the theoretical minimal score of difference one could achieve with infinite practice.

RESULTS

There were significant differences in practices with the first colposcopist using an 18-mm loop and the second colposcopist a 15-mm loop in the majority of cases. The median absolute and percentage difference between the presumed and actual excised depth was 2 mm and 16.6 % and 3.5 mm and 35.4 % for the two colposcopists, respectively. A learning plateau was identified only for the first colposcopist. We found that auditing consecutive excisions decreased significantly the difference between the presumed and actual depth of excision with a learning plateau at 2.2 mm of absolute difference and 22.6 % of percentage difference and with a learning rate of 13 cervical excisions.

CONCLUSION

There might be a benefit in auditing our treatment practice as there seems to be a learning plateau through this method. HIPPOKRATIA 2018, 22(3): 113-121.

Treatment of Achalasia with Per-Oral Endoscopic Myotomy: Analysis of 50 Consecutive Patients

BACKGROUND

Peroral endoscopic myotomy (POEM) has become an acceptable incisionless treatment for achalasia based on encouraging outcomes in multiple series worldwide. This report reflects our early experience.

METHODS

Data were collected prospectively on all patients undergoing POEM between June 2011 and April 2016 under IRB approval. Diagnosis of achalasia was confirmed by standard preoperative work-up. Primary outcome was symptom relief, measured by Eckardt score. Secondary outcomes were operative time, length of stay (LOS), adverse events, failure, and recurrence.

RESULTS

Fifty patients were included; 30 were female. Mean age was 55.7 ± 17.7 years. Mean BMI was 29.5 ± 9.2. Median OR time was 133.5 minutes (range 70-462); average myotomy was 13.1 ± 2.3 cm. One early case was converted to a laparoscopic Heller myotomy due to extensive submucosal fibrosis from a recent Botox injection. Two cases were aborted; one due to extensive submucosal fibrosis and the other to intraoperative capnopericardium. Median LOS was 1 day (range 0.8-8). Two major complications occurred: intraoperative cardiac arrest due to capnopericardium and postoperative submucosal hemorrhage. There were no deaths. Mean postoperative Eckardt score was 1.0 ± 1.9 (range 0-8) at 2-6 weeks (vs. preoperative score 7.7 ± 2.8; P < .0001); mean dysphagia component 0.35 ± 0.28 (vs. preoperative score 2.6 ± 0.7; P < .0001). Two recurrences were identified, both at 6 months.

CONCLUSIONS

POEM is a safe and durable treatment for achalasia in the short term. We demonstrated marked improvement of symptoms in all completed cases. There was an acceptable serious adverse event rate of 4%, failure of 6% due to patient selection, and recurrences occurring in only 4% of cases.

Adverse events during and after per-oral endoscopic myotomy: prevention, diagnosis, and management

Per-oral endoscopic myotomy (POEM) has surfaced as an effective endoscopic treatment modality for achalasia cardia (AC). Promising results in short- and mid-term follow-up studies have increased the use of POEM for the management of AC. POEM can be safely performed in an endoscopy suit, and major adverse events (AEs) are uncommon. AEs encountered during POEM or during the perioperative period principally include insufflation-related AEs, mucosal injuries, bleeding, pain, and aspiration pneumonia. Most insufflation-related AEs do not require an active intervention and therefore should not be considered as AEs in the true sense. When management of AEs is required, most intraoperative AEs can be managed at the same time without untoward consequences. Occurrences of AEs lessen after completion of the learning curve. However, experience alone does not ensure "zero" incidence of AEs, and early recognition remains essential. Postoperative AEs, like leaks, delayed bleeding, and delayed mucosal perforations, may pose special challenges for diagnosis and management. There is no standardized classification system for grading the severity of AEs associated with POEM, resulting in wide variation in their reported occurrences. Uniform reporting of AEs is not only crucial to comprehensively analyze the safety of POEM but also for comparison with other established treatment modalities like Heller's myotomy. GERD is an important long-term AE after POEM. Unlike the perioperative AEs, little is known regarding the intraoperative or patient-related factors that influence the occurrence of post-POEM GERD. Large prospective studies with long-term follow-up are required to determine the procedural factors associated with GERD after POEM.

Outcome of peroral endoscopic myotomy in achalasia cardia: Experience with a new triangular knife

BACKGROUND AND AIM

Peroral endoscopic myotomy (POEM) is a technically demanding procedure. Recently, a new triangular knife with integrated water jet function (TTJ) has been introduced. The present study was aimed to analyze and compare the operating time, efficacy, and adverse events (AEs) between the conventional (TT knife) and new knife (TTJ).

PATIENTS AND METHODS

All patients with achalasia cardia (AC) who underwent POEM between August 2015 and November 2016 were analyzed retrospectively. Operating time (OT), technical success, and AEs were assessed and compared between TT and TTJ knife.

RESULTS

A total of 193 patients with AC underwent POEM during the specified period. Both groups had equivalent number of different subtypes of AC (I, II, and III). There was no difference in technical success between the two groups (TT, 99% vs TT, 98.9%). OT was significantly less in the TTJ group as compared to TT group (53.8 ± 15.2 vs 66.26 ± 19.2; P = 0.0001). On subanalysis, OT taken for submucosal tunneling was significantly less with TTJ knife (34.6 ± 10.1 vs 45.83 ± 14.80), whereas OT was similar for myotomy and clipping in both the groups. Significantly fewer use of coagulation forceps and exchanges of accessories were required in TTJ knife group (2.92 ± 1.77 vs 10.5 ± 3.58; P = 0.0001). There were no major AEs. Minor AEs were noted in 21.5% and 31% of patients in TTJ and TT knife groups, respectively.

CONCLUSION

New triangular knife reduces procedure time and technical difficulty with POEM. POEM is an efficacious treatment for achalasia and can be safely executed in an endoscopy unit.

Learning curve for laparoscopic Heller myotomy and Dor fundoplication for achalasia

Purpose

Although laparoscopic Heller myotomy and Dor fundoplication (LHD) is widely performed to address achalasia, little is known about the learning curve for this technique. We assessed the learning curve for performing LHD.

Methods

Of the 514 cases with LHD performed between August 1994 and March 2016, the surgical outcomes of 463 cases were evaluated after excluding 50 cases with reduced port surgery and one case with the simultaneous performance of laparoscopic distal partial gastrectomy. A receiver operating characteristic (ROC) curve analysis was used to identify the cut-off value for the number of surgical experiences necessary to become proficient with LHD, which was defined as the completion of the learning curve.

Results

We defined the completion of the learning curve when the following 3 conditions were satisfied. 1) The operation time was less than 165 minutes. 2) There was no blood loss. 3) There was no intraoperative complication. In order to establish the appropriate number of surgical experiences required to complete the learning curve, the cut-off value was evaluated by using a ROC curve (AUC 0.717, p < 0.001). Finally, we identified the cut-off value as 16 surgical cases (sensitivity 0.706, specificity 0.646).

Conclusion

Learning curve seems to complete after performing 16 cases.

Anesthesia in per-oral endoscopic myotomy: A large tertiary care centre experience

BACKGROUND AND OBJECTIVES

Per-oral endoscopic myotomy (POEM) is safe and efficacious for the management of achalasia cardia (AC). POEM is usually performed under general anesthesia in an endoscopy suite or operating theatre. The current study was conducted with the aim to analyse anesthetic management of patients with AC who underwent POEM at our institution.

METHODS

We retrospectively analysed the data of patients with AC who underwent POEM at our institution from January 2013 to September 2016. All cases were performed in an endoscopy suite under supervision of an anesthesia management team. Pre-procedure endoscopic evacuation of esophagogastric contents was done in all cases. Management strategies used for gas-related adverse events and outcomes were assessed.

RESULTS

Four hundred and eighty patients (median age 40 years, range 4-77 years) underwent POEM during the study period. The sub-types of AC were type I (163), type II (297), and type III (20). POEM was successfully completed in 97.5% patients. Gas-related events were noted in 30.6% cases including-capno-thorax in 1%, capno-peritoneum in 12.3%, retroperitoneal air in 16.5%, capno-mediastinum in 0.2%, and capno-pericardium in 0.4% patients. Significant rise in end tidal CO2 (> 45) and peak airway pressure were observed in 8.1% and 5.4% cases, respectively. Drainage was required in 12.3% patients. There was no occurrence of aspiration during or after POEM.

CONCLUSIONS

POEM could be safely performed in an endoscopy suite under supervision of an expert anesthesia management team. Gas-related adverse events were common during POEM and could be managed with a standardized approach.