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

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.

Efficacy and Safety of Peroral Endoscopic Myotomy (POEM) in Achalasia: An Updated Meta-analysis

Background: Heller myotomy has been considered the standard surgical treatment for patients with achalasia. Since the initiation of peroral endoscopic myotomy (POEM), it has represented an alternative for treating patients with achalasia. Over the years, numerous prospective and retrospective studies with POEM use for achalasia have been published. We performed a systematic review and meta-analysis to evaluate the efficacy and safety of POEM in patients with achalasia. Methods: Publications investigating the safety and efficacy of POEM in patients with achalasia were searched in Medline, Ovid Journals, Medline non-indexed citations, and Cochrane Central Register of Controlled Trials and Database of Systematic Reviews. Pooling was conducted by both fixed and random effects models. Results: The initial search identified 328 reference articles; of these, 34 relevant articles were selected and reviewed. Data was extracted from 20 studies (n=1753) which met the inclusion criteria. In pooled analysis, the clinical success of POEM at 3 months was 94% (95% CI=93-95). The pooled clinical success of POEM at 12 months was 91% (95% CI=90-92). The pooled rate of gastroesophageal reflux disease (GERD) was 21% (95% CI=19-23), esophagitis was reported in 16% (95% CI=15-18), pneumomediastinum in 4% (95% CI=3-6), cervical emphysema in 12% (95% CI=10-13), pneumoperitoneum in 8% (95% CI=7-10), pneumothorax in 5% (95% CI=4 - 6), pleural effusion in 3% (95% CI=2-3), post-operative bleeding in 4.29% (95% CI=1.91 -7.61) and aspiration pneumonia in 3.08% (95% CI=1.13-5.97) of the patients after POEM. Conclusion: This meta-analysis suggests that POEM is a highly effective and safe endoscopic treatment for patients with achalasia and a reasonable alternative to Heller myotomy.

A Look into the Future of Endoscopic Submucosal Dissection and Third Space Endoscopy: The Role for Robotics and Other Innovation

Endoscopic resection has been widely applied especially in endoscopic submucosal dissection and third space endoscopy (TSE). Flexible endoluminal robotics allow performance of endoscopic submucosal dissection with exposure of the submucosal plane for precise dissection using two robotic arms. The introduction of TSE revolutionized the horizon of therapeutic endoscopy to the submucosal space beneath and beyond the mucosa. Advantages of TSE include avoidance of full thickness incision in gastrointestinal tract through the submucosal tunneling for performance of peroral endoscopic myotomy and submucosal tunneling endoscopic resection. In future, robotic-driven devices should be developed to enhance performance of complex endoluminal procedures and TSE.

Peroral endoscopic longer vs shorter esophageal myotomy for achalasia treatment: A systematic review and meta-analysis

BACKGROUND

Peroral endoscopic myotomy (POEM) has been demonstrated to be safe and effective in the treatment of achalasia. Longer myotomy is the standard POEM procedure for achalasia but when compared with shorter myotomy, its effectiveness is not as well known.

AIM

To compare the clinical effectiveness of longer and shorter myotomy.

METHODS

PubMed, EmBase, Cochrane Library, web of science and clinicaltrials.gov were queried for studies comparing shorter and longer POEM for achalasia treatment. The primary outcome was clinical success rate. Secondary outcomes comprised of operative time, adverse events (AEs) rate, gastroesophageal reflux disease (GERD) and procedure-related parameters. The Mantel-Haenszel fixed-effects model was primarily used for the analysis. Publication bias was assessed.

RESULTS

Six studies were included in this analysis with a total of 514 participants. During the follow-up period of 1-28.7 mo, longer and shorter myotomy in treating achalasia showed similar excellent effectiveness [overall clinical success (OR = 1, 95%CI: 0.46-2.17, P = 1, I²: 0%; subgroup of abstract (OR = 1.19, 95%CI: 0.38 to 3.73; P = 0.76; I²: 0%); subgroup of full text (OR = 0.86 95%CI: 0.30 to 2.49; P = 0.78; I²: 0%)]. Shorter myotomy had significantly reduced mean operative time compared with the longer procedure. There were no statistically significant differences in AEs rates, including GERD (overall OR = 1.21, 95%CI: 0.76-1.91; P = 0.42; I²: 9%; subgroup of abstract OR = 0.77, 95%CI: 0.40-1.47; P = 0.43; I²: 0%; subgroup of full text OR = 1.91, 95%CI: 0.98-3.75; P = 0.06; I²: 0%), hospital stay (overall MD = -0.07, 95%CI: -0.30 to 0.16; P = 0.55; I²: 24%; subgroup of abstract MD = 0.20, 95%CI: -0.25 to 0.65; P = 0.39; I²: 0; subgroup of full text MD = -0.16, 95%CI: -0.42 to 0.10; P = 0.23; I²: 42%), and major bleeding (overall OR = 1.25, 95%CI: 0.58-2.71; P = 0.56; I²: 0%) between the two procedures. These differences remained statistically non-significant in all sensitivity analyses.

CONCLUSION

POEM was effective in treating achalasia. Shorter and longer myotomy procedures provided similar therapeutic effects in terms of long-term effectiveness. In addition, shorter myotomy reduced the operative time.

Peroral endoscopic shorter versus longer myotomy for the treatment of achalasia: a comparative retrospective study

INTRODUCTION

Peroral esophageal myotomy (POEM) is a novel endoscopic treatment for achalasia. It has gained popularity worldwide among surgeons and endoscopists, but no studies have compared peroral endoscopic short with long myotomy for achalasia. We aimed to compare the clinical efficacy and safety between peroral endoscopic shorter and longer myotomy.

METHODS

The retrospective study enrolled 129 achalasia patients who underwent POEM from July 2011 to September 2017. Based on the myotomy length (ML), patients were divided into shorter myotomy (SM) group (ML ≤ 7 cm, n = 36) and longer myotomy (LM) group (ML > 7 cm, n = 74). Procedure-related parameters, symptom scores, adverse events and manometric data were compared between two groups.

RESULTS

The mean ML was 6.0 ± 0.6 cm in SM group, and 11.5 ± 3.1 cm in LM group (p < 0.001). The mean operation time was significantly less in SM group than LM group (46.6 ± 18.5 min vs 62.1 ± 25.2 min, p = 0.001). During a mean follow-up period of 28.7 months, treatment success (Eckardt score ≤ 3) was achieved in 94.4% (34/36) of patients in SM group and 91.9% (68/74) in LM group (p = 0.926). There was no statistical difference in the incidence of intraoperative complications (8.4% vs 8.2%, p = 0.823) and reflux rate (8.3% vs. 14.9%, p = 0.510) between two groups.

CONCLUSIONS

Peroral endoscopic shorter myotomy is comparable with longer myotomy for treating achalasia with regard to clinical efficacy and has the advantage of shorter procedure time.

Per oral endoscopic tumor (POET) resection for treatment of upper gastrointestinal subepithelial tumors

BACKGROUND

Endoscopic submucosal tunneling has evolved to allow endoscopic resection of subepithelial tumors of gastrointestinal tract without full-thickness perforation. This study aimed to investigate safety and efficacy of submucosal tunnel resection for these tumors.

METHOD

Patients with subepithelial tumors (SET) located in esophagus, gastric cardia, lesser curvature, and antrum were recruited. The size of tumor was limited to < 40 mm. The procedures were performed under general anesthesia. A mucosal entrance was created 2 cm proximal to the SET after submucosal injection. Submucosal tunnel was then extended and the tumor was dissected and mobilized with intact overlying mucosa. After complete dissection, the tumors would be retrieved per orally and mucosal entrance closed by endoclips.

RESULTS

From June 2012 to December 2016, 51 patients with subepithelial tumors received POET. 39 patients had SET in stomach, 11 located in esophagus, and 1 in duodenum. The mean operative time was 90.46 ± 46.49 min, while the mean size of the tumors was 20.71 ± 14.05 mm. The POET was converted to endoscopic full-thickness resection (EFTR) in three patients with gastric subepithelial tumors located at greater curvature. The overall complication rate was 4.0%, and there was no bleeding, mucosal dehiscence, or leakage. The time to resume diet was 1.7 days, while the average hospital stay was 3.2 ± 1.0 days. The mean follow-up period was 19 ± 16 months, and only 1 patient developed recurrence of leiomyoma.

CONCLUSION

Per oral endoscopic tumor resection is safe and effective treatment for esophageal and gastric SET located at cardia, lesser curvature, and antrum. Currently, POET for treatment of upper GI SET is limited by the size and location of the tumor.

Efficacy of anterior versus posterior per-oral endoscopic myotomy for treating achalasia: a randomized, prospective study

BACKGROUND AND AIMS

Per-oral endoscopic myotomy (POEM) has been demonstrated to be safe and effective for treating achalasia. Two approaches-anterior myotomy and posterior myotomy-are used during POEM. However, little is known about the comparison between the 2 different approaches. The objective of the study is to compare the safety and short-term efficacy of the 2 approaches for treating achalasia.

METHODS

From October 2015 to December 2016, 63 consecutive patients with achalasia without prior treatment or sigmoid-type esophagus were prospectively recruited. They were randomly assigned to an anterior or posterior myotomy group. Clinical data about general characteristics, operative parameters, pre- and postoperative Eckardt score, esophageal manometry results, 24-hour pH test, and adverse events were recorded and compared between the 2 groups.

RESULTS

The anterior group included 31 patients and the posterior group 32 patients. All patients underwent POEM successfully, and treatment success (defined as an Eckardt score ≤3) was achieved in all patients during a mean follow-up of 15.5 months. Mean Eckardt score, lower esophageal sphincter pressure, and 4-second integrated relaxation pressure were significantly decreased (6.2 ± 1.3, 37.5 ± 6.7 mm Hg, and 27.3 ± 4.9 mm Hg vs .70 ± .70, 12.8 ± 2.8 mm Hg, and 11.1 ± 2.3 mm Hg, respectively; P < .01). There was no significant difference between the 2 groups in terms of general characteristics, treatment success, pre- and postoperative esophageal manometry, Eckardt score, and adverse events (P > .05).

CONCLUSIONS

The short-term treatment efficacy, manometry outcomes, and adverse events were comparable between the anterior and posterior myotomy groups. Large-scale studies with long-term follow-up are warranted for a more definitive conclusion. (Clinical trial registration number: ChiCTR-ICR-15007211.).

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.

An Update on Current Management Strategies for Achalasia and Future Perspectives

The last decade has seen growing insight into the pathophysiology of achalasia, and current treatments decreasing the resting pressure in the lower esophageal sphincter by endoscopic (botulinum toxin injection, pneumatic dilation, peroral endoscopic myotomy) or surgical means (Heller myotomy). Manometry is considered the gold standard to confirm the diagnosis of achalasia. Pneumatic dilation and laparoscopic Heller myotomy have similar effectiveness and are both more successful in patients with type II achalasia. Laparoscopic myotomy when combined with partial fundoplication is an effective surgical technique and has been considered the operative procedure of choice until recently. Peroral endoscopic myotomy is an emerging therapy with promising results since it offers a minimally invasive and efficacious option especially in type III achalasia. However, it remains to be determined if peroral endoscopic myotomy offers long-term efficacy.

The current state of per oral endoscopic myotomy for achalasia

Achalasia is an acquired neuromuscular disorder that has been treated using a variety of modalities throughout medical history. Recently, the technique of per oral endoscopic myotomy (POEM) was introduced to treat the disease using a truly minimally invasive, natural orifice technique that is rapidly being adopted across the world. This review outlines the development of POEM, the technique itself, and gives a comparison to other procedures, specifically laparoscopic Heller myotomy (LHM).

In vivo experience with peroral endoscopic myotomy: An essential activity for developing the technique in humans

INTRODUCTION AND OBJECTIVES

Achalasia is the most widely studied esophageal motility disorder. No treatment has achieved completely satisfactory results. The laparoscopic Heller esophagomyotomy is currently the most accepted technique. With the advent of minimally invasive surgery, the appearance of peroral endoscopic myotomy (POEM) has promising results. The primary aim of our study was to perform peroral endoscopic esophagomyotomy in animal experimentation models to perfect the technique and later apply it to humans. The secondary aims were to evaluate the intraoperative and postoperative complications and to describe the anatomopathologic findings.

MATERIALS AND METHODS

An experimental study was conducted on 8 live porcine models that were followed for 30 days to identify postoperative complications. Necropsy was then performed to evaluate the histopathologic findings. The international requirements and regulations for animal experimentation were met.

RESULTS

The technique was carried out in all the models. There was one intraoperative death. Pneumothorax was observed in 50% of the units in experimentation and subcutaneous cervical emphysema in 75%, with no significant clinical repercussions. Histologic muscle layer (myotomy) involvement was above the gastroesophageal junction in 87% of the cases and below it in 25%.

CONCLUSION

Peroral endoscopic esophagomyotomy is a feasible, albeit complex, procedure that requires advanced training, and thus should be performed in highly specialized centers. Specific skills in advanced therapeutic endoscopic procedures of this type must continue to be developed through continuing education (ideally in in vivo models), to then be performed on humans.

Health-Related Quality of Life and Physiological Outcomes of Peroral Endoscopic Myotomy for Achalasia

BACKGROUND

Peroral endoscopic myotomy (POEM) has gained acceptance as a treatment for achalasia. The aim of this study was to assess symptomatic, quality of life (QoL), and physiological outcomes of POEM using standardized methods.

MATERIALS AND METHODS

Patients who were planned to undergo POEM were evaluated pre- and postoperatively with timed barium esophagogram (TBE), high-resolution manometry (HRM), the achalasia symptom questionnaire (ASQ) (best score 10, worst score 31), and the short form (SF)-36 (best score 100, worst score 0). Nine patients completed postoperative HRM, TBE, and 48 hours esophageal pH monitoring. A P-value of <.05 was considered statistically significant.

RESULTS

A total of 34 of 37 patients completed the POEM procedure. There was improvement in the ASQ scores and in QoL. HRM integrated relaxation pressures (IRPs) improved from 31.4 ± 10.8 mmHg preoperatively to 12.3 ± 6.7 mmHg postoperatively, and lower esophageal sphincter pressure (LESP) improved from 49.1 ± 16.9 mmHg preoperatively to 23.1 ± 9.4 mmHg postoperatively. Of the 7 patients who were evaluated with 48-hour pH monitoring postoperatively, 5 patients (71%) demonstrated pathological reflux with an average Demeester score of 23.1 ± 19.1. There was a negative linear correlation between LESP change and Demeester scores (r = -0.7, P = .03).

CONCLUSION

The POEM procedure significantly improves achalasia-related symptoms and improves social functioning. Physiologically, there is reduction in both IRP and LESP. Postoperative pathological reflux is correlated with LESP reduction.

A multicenter international registry of redo per-oral endoscopic myotomy (POEM) after failed POEM

BACKGROUND AND AIMS

Per-oral endoscopic myotomy (POEM) has become an accepted treatment for patients with achalasia. Despite its excellent efficacy rate of greater than 80%, a small percentage of patients remain symptomatic after the procedure. Limited data exist as to the best management for recurrence of symptoms after POEM. We present the first international, multicenter experience on the efficacy and safety of a repeat POEM in the management of achalasia.

METHODS

Patients who underwent a redo POEM from 15 centers in 9 countries were included in a dedicated registry. Technical success was defined as successful completion of a second myotomy. Clinical success was defined as an Eckardt score of less than or equal to 3 after the second myotomy. Adverse events including anesthesia-related, operative, and postoperative adverse events were recorded.

RESULTS

Forty-six patients were included in the study. The average age was 49.3 ± 16.78 years. Twenty (45%) patients were male. The mean pre-redo-POEM Eckardt score was 4.3 ± 2.48. Technical success was achieved in 46 (100%) patients. Clinical success was achieved in 41 patients (85%). The average post-POEM Eckardt score was 1.64 ± 1.67, with a significant difference of 2.58 (P < .00001). Eight patients (17%) had adverse events consisting of procedural bleeding, all managed endoscopically. There were no deaths. No POEMs were aborted or required surgical conversion or assistance.

DISCUSSION

For patients with persistent symptoms after POEM, repeat POEM appears to be an efficacious and safe technique. Further randomized trials comparing redo POEM versus Heller should be considered. (Clinical trial registration number: NCT02162589.).

Functional restoration of the esophagus after peroral endoscopic myotomy for achalasia

Purpose

Peroral endoscopic myotomy (POEM) is a new efficacious treatment option for achalasia. We propose to define “esophageal remodeling” as the functional restoration of the esophagus that involves decreased lower esophageal sphincter (LES) pressure, recovery of esophageal body peristalsis, and reduction of luminal diameter. The aim of this study was to investigate “esophageal remodeling” after POEM for achalasia.

Materials and methods

We analyzed data from a prospectively collected database of POEM subjects, which included preoperative and 2-month postoperative Eckardt symptom scores, and results from esophageal high resolution manometry (HRM) and barium esophagogram (BE). We recruited 23 patients (13 male; mean age: 53.9 years) whose preoperative and postoperative HRM and BE results were available, from among 30 patients with achalasia who underwent POEM at two institutions between July 2013 and December 2015.

Results

All patients achieved clinical treatment success (Eckardt score≤3). Partial recovery of esophageal body peristalsis was noted in 1/5 patients with type I (20%), 6/11 with type II (54.5%), and 7/7 with type III (100%) achalasia after POEM. Pan-esophageal pressurization disappeared after POEM in 10/11 type II achalasia patients. The average diameter of the esophageal body after POEM was significantly decreased in all types of achalasia.

Conclusion

POEM provided excellent clinical symptomatic relief and esophageal remodeling in terms of restoration of peristalsis and reduction in diameter of the esophageal body, especially in patients with type III achalasia.

Long-term outcomes of per-oral endoscopic myotomy in patients with achalasia with a minimum follow-up of 2 years: an international multicenter study

BACKGROUND AND AIMS

Per-oral endoscopic myotomy (POEM) has shown promising safety and efficacy in short-term studies. However, long-term follow-up data are very limited. The aims of this study were to assess (1) clinical outcome of patients with a minimum post-POEM follow-up of 2 years and (2) factors associated with long-term clinical failure after POEM.

METHODS

A retrospective chart review was performed that included all consecutive patients with achalasia who underwent POEM with a minimum follow-up of 2 years at 10 tertiary-care centers. Clinical response was defined by a decrease in Eckardt score to 3 or lower.

RESULTS

A total of 205 patients (45.8% men; mean age, 49 years) were followed for a median of 31 months (interquartile range, 26-38 months). Of these, 81 patients (39.5%) had received previous treatment for achalasia before POEM. Clinical success was achieved in 98% (185/189), 98% (142/144), and 91% (187/205) of patients with follow-up within 6 months, at 12 months, and ≥24 months, respectively. Of 185 patients with clinical response at 6 months, 11 (6%) experienced recurrent symptoms at 2 years. History of previous pneumatic dilation was associated with long-term treatment failure (odds ratio, 3.41; 95% confidence interval, 1.25-9.23). Procedure-related adverse events occurred in 8.2% of patients and only 1 patient required surgical intervention. Abnormal esophageal acid exposure and reflux esophagitis were documented in 37.5% and 18% of patients, respectively. However, these rates are simply a reference number among a very selective group of patients.

CONCLUSIONS

POEM is safe and provides high initial clinical success and excellent long-term outcomes. Among patients with confirmed clinical response within 6 months, 6% had recurrent symptoms by 2 years.

Peroral endoscopic myotomy: procedural complications and pain management for the perioperative clinician

Achalasia refers to the lack of smooth muscle relaxation of the distal esophagus. Although nonsurgical treatments such as pneumatic dilatation of the distal esophagus and botulinum toxin injections have been performed, these procedures have limited duration. Similarly, surgical treatment with Heller myotomy is associated with complications. At our institution, we perform the peroral endoscopic myotomy (POEM) in qualified patients. Briefly, POEM involves endoscopic creation of a mid-esophageal submucosal bleb, creation of a submucosal tunnel with the endoscope, and then a distal myotomy, resulting in relaxation of the distal esophagus. The aim of our study is to document perioperative pain and associated pain management for our initial patients undergoing POEM and to review the literature for perioperative complications of this procedure. Therefore, anesthetic and pain management for our initial eleven patients undergoing POEM were reviewed. Patient demographics, pre-POEM pain medication history, perioperative pain medication requirements, and post-POEM pain scores were examined. We found post-POEM pain was usually in the mild–moderate range; a combination of medications was effective (opioids, nonsteroidal anti-inflammatory drugs, acetaminophen). Our literature search revealed a wide frequency range of complications such as pneumoperitoneum and subcutaneous emphysema, with rare serious events such as capnopericardium leading to cardiac arrest. In conclusion, our experience with POEM suggests pain and can be managed adequately with a combination of medications; the procedure appears to be safe and reasonable to perform in an outpatient endoscopy unit.

[Tension pneumothorax during peroral endoscopic myotomy for treatment of esophageal achalasia under general anesthesia]

More and more endoscopically gastrointestinal procedures require anesthesiologists to perform general anesthesia, such as "peroral endoscopic myotomy". Peroral endoscopic myotomy is a novel invasive treatment for the primary motility disorder of esophagus, called esophageal achalasia. Despite of its minimally invasive feature, there are still complications during the procedure which develop to critical conditions and threat patients' lives. Herein we describe a case about tension pneumothorax subsequent to esophageal rupture during peroral endoscopic myotomy. The emergent management of the complication is stated in detail. The pivotal points of general anesthesia for patients undergoing peroral endoscopic myotomy are emphasized and discussed. Also, intraoperative and post-operative complications mentioned by literature are integrated.

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

Peroral endoscopic myotomy (POEM) is a novel approach to performing esophageal myotomy for the treatment of achalasia. This review aims to assess subjective and objective metrics of achalasia treatment efficacy, perioperative adverse events and the incidence of postoperative gastroesophageal reflux disease in patients treated with POEM. Secondary aims include a pooled analysis comparison of the clinical outcomes and procedural safety of POEM versus laparoscopic Heller's myotomy (LHM). A systematic review of the literature, up to and including January 15, 2015, was conducted for studies reporting POEM outcomes. Studies comparing POEM to LHM were also included for the purpose of pooled analysis. Outcomes from 1122 POEM patients, from 22 studies, are reported in this systematic review. Minor operative adverse events included capno/pneumo-peritoneum (30.6%), capno/pneumo-thorax (11.0%) and subcutaneous emphysema (31.6%). Major operative adverse events included mediastinal leak (0.3%), postoperative bleeding (1.1%) and a single mortality (0.09%). There was an improvement in lower esophageal sphincter pressure and timed barium esophagram column height of 66% and 80% post-POEM, respectively. Symptom improvement was demonstrated with a pre- and post-POEM Eckardt score ± standard deviation of 6.8 ± 1.0 and 1.2 ± 0.6, respectively. Pre- and post-POEM endoscopy showed esophagitis in 0% and 19% of patients, respectively. The median (interquartile range) points scored for study quality was 15 (14-16) out of total of 32. Pooled analysis of three comparative studies between LHM and POEM showed similar results for adverse events, perforation rate, operative time and a nonsignificant trend toward a reduced length of hospital stay in the POEM group. In conclusion, POEM is a safe and effective treatment for achalasia, showing significant improvements in objective metrics and achalasia-related symptoms. Randomized comparative studies of LHM and POEM are required to determine the most effective treatment modality for achalasia.

Complications of submucosal endoscopy

Submucosal endoscopy essentially regroups peroral endoscopic esophageal myotomy (POEM) and, more recently, pyloromyotomy and tunnel tumor resections. The complication rate of POEM is between 5% and 10%. Complications include gas-related complications, mucosal tears, and bleeding, and are usually managed conservatively or with non-surgical procedures. Only one case of death has been reported. The most commonly identified risk factors for complicated procedures in POEM are short experience with the technique and sigmoid-type esophagus. The rate of gastro-esophageal reflux (GERD) is between 10% and 30% depending on the definitions, with a good clinical response to proton pump inhibitors. For the techniques other than POEM, the number of cases reported is too small to allow identification of the complications, which, in addition, probably vary depending on the organ involved. The management of gas-related complications is conservative and sometimes requiring percutaneous exsufflation (capnoperitoneum) or drainage. The endoscopic management of mucosal tears essentially involves clip placement and, in case of bleeding, the usual hemostasis techniques including stent placement. Importantly, following a rigorous and appropriate learning program is essential to minimize the risk of complications, particularly for specialists with a short experience in the technique.

Safety and efficacy of POEM for treatment of achalasia: a systematic review of the literature

INTRODUCTION

Peroral endoscopic myotomy (POEM) is a novel intervention for the treatment of achalasia, which combines the advantages of endoscopic access and myotomy. The purpose of this study was to perform a systematic review of the literature to evaluate the efficacy and safety of POEM.

METHODS

The systematic review was conducted following the PRISMA guidelines. Evidence-Based Medicine Reviews, Cochrane Central Register of Controlled Trials, Ovid MEDLINE (R) including in-process and non-indexed citations were searched for POEM studies using the keywords: esophageal achalasia, POEM, endoscopy, natural orifice surgery, laparoscopic Heller myotomy (LHM), and related terms. Eckardt score, lower esophageal sphincter (LES) pressure, and reported complications were the main outcomes. Two authors reviewed the search result independently. A third reviewer resolved all disagreements. Data abstraction was pilot-tested and approved by all authors. Data were examined for clinical, methodological, and statistical heterogeneity with the aim of determining whether evidence synthesis using meta- analysis was possible.

RESULTS

The search strategy retrieved 2894 citations. After removing duplicates and applying the exclusion criteria, 54 studies were selected for full-text review of which a total of 19 studies were considered eligible for further analysis. There were 10 retrospective and 9 prospective studies, including 1299 POEM procedures. No randomized control trial (RCT) was identified. Overall, the pre- and post-POEM Eckardt scores and LES pressure were significantly different. The most frequently reported complications were mucosal perforation, subcutaneous emphysema, pneumoperitoneum, pneumothorax, pneumomediastinum, pleural effusion, and pneumonia. The median follow-up was 13 months (range 3-24).

CONCLUSION

POEM is a safe and effective alternative for the treatment of achalasia. However, only short-term follow-up data compared with LHM are available. RCTs and long-term follow-up studies are needed to establish the efficacy and safety of POEM in the management of patients with achalasia.

Factors predicting the technical difficulty of peroral endoscopic myotomy for achalasia

BACKGROUND

Peroral endoscopic myotomy (POEM) has been described as a novel treatment for esophageal achalasia. Owing to its technical difficulty, POEM is not widely performed. This study was aimed to prospectively assess the factor predicting technical difficulty of POEM in a single center with large volume cases.

METHODS

A total of 105 cases of achalasia treated by POEM from April 2011 to September 2014 were analyzed. Difficult cases of POEM were defined as procedure time ≥90 min and occurrence of adverse events, including mucosal perforation, pneumothorax, and major bleeding. Univariate and multivariate logistic regression analyses were performed to assess the predictive factors of difficult POEM.

RESULTS

POEM was successfully completed in all the patients, and no one was converted to laparoscopy. The number of cases with procedure time ≥90 min was 17. Mucosal perforations occurred in six (5.7 %) patients during submucosal tunnel creation, major bleeding occurred in seven (6.7 %) patients, and pneumothorax occurred in six (5.7 %) patients immediately after procedure. All the complications were managed conservatively. No other intraoperative and immediate postoperative complications, including infections and pneumoperitoneum, occurred. Multivariate analysis showed that early period (odds ratio [OR] 4.173, 95 % confidence interval [95 % CI] 1.36-6.829, P = 0.023) and triangular tip knife ([OR] 6.712, [95 % CI] 1.479-30.460, P = 0.014) were independent factors associated with technical difficulty regarding longer procedure time (procedure time ≥90 min).

CONCLUSION

POEM is safe for the treatment of esophageal achalasia. Triangular tip knife and early period were independent risk factors for longer procedural time.

Prospective evaluation of CT esophagram findings after peroral endoscopic myotomy

BACKGROUND AND AIMS

Peroral endoscopic myotomy (POEM) is a procedure with potential for serious adverse events. Postprocedure imaging is routinely done, yet there is no consensus on the optimal imaging protocol. We describe a novel and simple CT esophagram protocol for evaluation after POEM and for reporting the full spectrum of radiographic findings and subsequent interventions.

METHODS

This was a single-center prospective study of consecutive patients treated with POEM evaluated with CT esophagram.

RESULTS

Eighty-four consecutive patients who had POEM performed underwent CT esophagrams. The most common findings were pneumomediastinum (85.7%), pneumoperitoneum (66.7%), subcutaneous emphysema (52.4%), and pleural effusion (46.4%). Other findings included retroperitoneal air (38.1%), pneumothorax (19%), atelectasis (14.3%), intramural air in the esophagus and/or stomach (13.1%), pericardial effusion (2.4%), and pneumopericardium (2.4%). Five patients required intervention based on CT findings. In 1 patient, a leak was detected on CT esophagram before any clinical manifestation, facilitating prompt intervention and avoiding potential serious outcomes. Four patients were diagnosed with pneumonia and were treated with antibiotics. There was frequent postprocedural atelectasis, which prompted the introduction of routine incentive spirometry in all postoperative POEM cases.

CONCLUSIONS

CT esophagram is a simple and accessible imaging test for routine postoperative POEM evaluation. Numerous and dramatic postprocedure radiographic findings may be expected and demonstrated with this imaging modality. Although most of these findings may not require intervention, some are of potential significance, and early identification may help modify postprocedure management. (

CLINICAL TRIAL REGISTRATION NUMBER

NCT01832779.).

Clinical response to peroral endoscopic myotomy in patients with idiopathic achalasia at a minimum follow-up of 2 years

BACKGROUND

The recently developed technique for peroral endoscopic myotomy (POEM) has been shown to be effective in several short-term studies. Longer term outcome data are largely non-existent.

OBJECTIVE

To systematically report clinical outcome with a minimum post-POEM follow-up of 2 years.

DESIGN

All patients treated consecutively by POEM for achalasia at three centres were retrospectively analysed, with a minimum follow-up of 2 years. The main outcome was the rate of POEM failures (Eckardt score >3) related to follow-up time.

RESULTS

Of 85 patients treated, five (5.9%) cases were excluded due to protocol violation or loss to follow-up; the remaining 80 patients (mean age 44.9 years, 54% men) were followed clinically for 29 months (range 24-41). Initial clinical response was observed in 77 cases (96.3%). Clinical recurrences (later failures) were seen in a further 14 cases (17.7%), accounting for a total failure rate of 21.5%. In a multivariate analysis, age and endoscopic reflux signs were independent predictors of treatment success. Of the 17 failures, eight were among the first 10 cases treated in the participating centres. Reflux-associated sequelae included one case of a severe reflux-associated stricture requiring dilatation, and two patients with minor transient Eckardt score elevations curable by proton pump inhibitor (PPI) treatment. Endoscopic signs of reflux oesophagitis, mostly Los Angeles grade A/B, were seen in 37.5% (37/72) at the 2-year control.

CONCLUSIONS

In this multicentre retrospective analysis, a high initial success rate of POEM is followed by a mid-term recurrence rate of 18%. Reflux oesophagitis, albeit mild, is frequent and should probably be treated by regular low-dose PPI therapy.

TRIAL REGISTRATION NUMBER

NCT 01405417 (UKE study).

Achalasia: current treatment options

Achalasia is a rare esophageal motility disorder, characterized by impaired swallow-induced, lower esophageal sphincter (LES) relaxation and defective esophageal peristalsis. Unfortunately, there are no etiological therapies for achalasia. Patients present with dysphagia, chest pain and regurgitation of undigested food, often leading to weight loss. The currently available treatments have the common aim of relieving symptoms by decreasing the pressure of the LES. This can be achieved with some medications, by inhibiting the cholinergic innervation (botulinum toxin), by stretching (endoscopic dilation) or cutting (surgery) the LES. Recently, other therapeutic options, including per-oral endoscopic myotomy have been developed and are gaining international consensus. The authors report on the benefits and weaknesses of the different therapies and provide an updated approach to the management of achalasia.

Peroral Endoscopic Myotomy for Esophageal Achalasia: Outcomes of the First 100 Patients With Short-term Follow-up

OBJECTIVE

Aim of this study is to report the mid-term outcomes of a large series of patients treated with peroral endoscopic myotomy (POEM) in a single European center.

BACKGROUND

POEM is a recently developed treatment of achalasia, which combines the efficacy of surgical myotomy, with the benefits of an endoscopic procedure. Previous studies, including few patients with a short-term follow-up, showed excellent results on dysphagia relief.

METHODS

The first 100 adult patients treated in a single tertiary referral center were retrospectively identified and included in this study (41 men, mean age 48.4 years). Patients were treated according to a standard technique. Follow-up data, including clinical evaluation, and results of esophagogastroduodenoscopy (EGD), manometry, and pH monitoring were collected and analyzed.

RESULTS

POEM was completed in 94% of patients. Mean operative time was 83 minutes (49-140  minutes). No complications occurred. Patients were fed after a median of 2 days (1-4 days). A mean follow-up of 11 months (3-24 months) was available for 92 patients. Clinical success was documented in 94.5% of patients. Twenty-four-hour pH monitoring documented Gastro-Esophageal Reflux Disease (GERD) in 53.4% of patients. However, only a minority of patients had heartburn (24.3%) or esophagitis (27.4%), and these patients were successfully treated with proton-pump inhibitors.

CONCLUSIONS

Our results confirm the efficacy of POEM in a large series of patients, with a mean follow-up of 11 months. Should our results be confirmed by long-term follow-up studies, POEM may become one of the first-line therapies of achalasia in the next future.

A Western Perspective on "New NOTES" from POEM to Full-thickness Resection and Beyond

Most new natural orifice translumenal endoscopic surgery procedures originated in Asia; therefore, most data come from operators and a health care environment different from those in the West. We provide a Western perspective. We discuss East-West differences; review areas in which the United States is leading the way; and discuss the vagaries of coding and reimbursement. In the United States, reimbursement remains problematic. A Current Procedural Terminology code for peroral endoscopic myotomy is inevitable given the rapidly accumulating overwhelmingly positive outcomes data. However, coordinated efforts may help accelerate the process.

POEM, the Prototypical "New NOTES" Procedure and First Successful NOTES Procedure

Peroral endoscopic myotomy (POEM) was first performed in 2008 as a novel treatment of achalasia. It is now performed globally, demonstrating the evolution of the first successful natural orifice transluminal endoscopic surgery (NOTES) procedure. There is extensive data demonstrating the safety and efficacy of POEM, and now long-term data has emerged demonstrating that the efficacy is durable. POEM is also being used to successfully treat diffuse esophageal spasm (DES) and jackhammer esophagus. With jackhammer esophagus and DES, inclusion of the lower esophageal sphincter in the myotomy minimizes the risk of symptom development from iatrogenic ineffective esophageal motility.

Peroral endoscopic myotomy for esophageal achalasia: outcomes of the first over 100 patients with short-term follow-up

BACKGROUND

POEM is a recently developed achalasia treatment method, which combines the efficacy of surgical myotomy with the benefits of endoscopic procedures. Very few studies have focussed on the efficacy and usefulness of POEM in over 100 cases.

METHODS

The first 100 adult patients treated according to standard POEM technique in a single center and followed up for 3 months were identified and included in this study (men 42; women 58; mean age 48.2 ± 18.8; range 9-91 years) The pre- and postoperative assessments included Eckardt scores, manometry, endoscopy, and monitoring pH.

RESULTS

Mean operative time was 150.8 ± 49.3 min (75-370 min). Adverse events over Grade IIIb by the Clavien-Dindo classification were not encountered. The mean preoperative and postoperative lower esophageal sphincter pressures were 43.6 ± 26.2 and 20.9 ± 12.7 mmHg, respectively, indicating a statistically significant decrease after POEM (P < 0.05). The mean preoperative and postoperative integrated relaxation pressure values were 33.5 ± 15.2 and 15.3 ± 6.5 mmHg (P < 0.05). Furthermore, the Eckardt score significantly decreased from 5.9 ± 2.5 preoperatively to 0.8 ± 0.9 postoperatively (P < 0.05). Clinical success was documented in 99 % of the patients. Short-term outcomes after POEM were extremely good and independent of the age, type of achalasia, and previous treatment method. The percent of monitoring time with a pH < 4 was 25.6 % (22/86) in patients not on proton-pump inhibitors. Nine patients were diagnosed with symptomatic gastroesophageal reflux disease (GERD); patients with reflux esophagitis and symptomatic GERD improved with PPI treatment.

CONCLUSIONS

Our results confirm the efficacy of POEM in a large patient series and support POEM as one of the first-line achalasia therapies in the near future.

Per Oral Endoscopic Myotomy for Achalasia: A Detailed Description of the Technique and Review of the Literature

Historically, the most robust outcomes in treatment of achalasia were seen with surgical myotomy. Per oral endoscopic myotomy (POEM) introduced an endoscopic method for creating a surgical myotomy. Thousands of cases of POEM have been performed; however, there is no standard technique, and the rates of clinical success and adverse events vary widely among centers. This article presents a detailed description of the POEM technique, including the rationale and potential pitfalls of the main variations, in the context of the international literature.

Greater curvature myotomy is a safe and effective modified technique in per-oral endoscopic myotomy (with videos)

BACKGROUND

Per-oral endoscopic myotomy (POEM) for achalasia with esophagocardiomyotomy in the lesser curvature (LC myotomy) is now established and accepted widely. However, in some cases LC myotomy is precluded by previous procedures, such as Heller myotomy, or by other anatomic considerations that obscure the normal dissection planes. It may also be difficult to identify the esophagogastric junction (EGJ), which can result in an incomplete gastric myotomy and poor rates of symptom relief. On the other hand, the angle of His is always located in the greater curvature of the stomach and serves as a consistent, definite landmark of the gastric side.

OBJECTIVE

To evaluate esophagocardiomyotomy in the greater curvature (GC myotomy) as an alternative POEM technique in cases where a prior LC myotomy or supervening anatomic constraints make identification of the EGJ technically challenging.

DESIGN

Prospective.

SETTING

Single-center study.

PATIENTS

Twenty-one achalasia patients who received POEM with GC myotomy.

INTERVENTIONS

POEM.

MAIN OUTCOME MEASUREMENTS

Efficacy and safety of GC myotomy measured in terms of reduction in lower esophageal sphincter (LES) pressures, improvement in Eckardt scores, and development of intraoperative or postoperative adverse events.

RESULTS

Identification of the EGJ was achieved in all cases, resulting in a mean gastric myotomy length of 2.6±1.1 cm. Mean LES pressure and Eckardt symptom scores decreased significantly (21.2±7.3 vs 10.5±2.7 mm Hg, 5 [2-8] vs 1 [0-5], respectively) (P<.01). Endoscopic evidence of gastroesophageal reflux was identified in 52% of patients (11/21) postmyotomy; however, only 9.5% (2/11) were symptomatic, and these patients were successfully controlled with proton pump inhibitors. No severe adverse events were encountered.

LIMITATIONS

Single center.

CONCLUSIONS

GC myotomy is a promising, safe modification of the POEM technique and may be especially useful in cases of redo POEM, POEM post-Heller myotomy, or when the EGJ is difficult to recognize because of supervening anatomic constraints.

Myotomy of Distal Esophagus Influences Proximal Esophageal Contraction and Upper Esophageal Sphincter Relaxation in Patients with Achalasia After Peroral Endoscopic Myotomy

BACKGROUND/AIMS

The motility change after peroral endoscopic myotomy (POEM) in achalasia is currently focused on lower esophageal sphincter (LES). This study aims to investigate the correlation of motility response between distal and proximal esophagus after POEM.

METHODS

A total of 32 achalasia patients who received POEM and high-resolution manometry (HRM) were included for analysis. Eckardt score was used to assess symptom improvement. HRM was applied for studying motility. Main parameters analyzed were (1) LES: resting pressure (restP), 4-second integrated relaxation pressure; (2) esophageal body (EB): contractile integral of distal segment with myotomy (CI-DM) and proximal segment without myotomy (CI-PNM); and (3) upper esophageal sphincter (UES): relaxation pressure (UES-RP).

RESULTS

There were 6 type I, 17 type II, and 9 type III achalasia patients included for analysis. (1) Eckardt score, LES tone, CI-DM, CI-PNM and UES-RP were reduced remarkably after POEM (P< 0.001). (2) no significant correlation was noted between LES tone and contractile intergral of EB. (3) a positive linear correlation of CI-DM and CI-PNM changes was detected (P< 0.001). (4) the change of UES-RP was positively correlated with the change of contractile integral of EB (P< 0.001).

CONCLUSIONS

Myotomy of the distal esophagus would attenuate proximal EB contraction and assist UES relaxation in achalasia patients after POEM.

Endoscopic treatment of esophageal achalasia

Achalasia is a motility disorder of the esophagus characterized by dysphagia, regurgitation of undigested food, chest pain, weight loss and respiratory symptoms. The most common form of achalasia is the idiopathic one. Diagnosis largely relies upon endoscopy, barium swallow study, and high resolution esophageal manometry (HRM). Barium swallow and manometry after treatment are also good predictors of success of treatment as it is the residue symptomatology. Short term improvement in the symptomatology of achalasia can be achieved with medical therapy with calcium channel blockers or endoscopic botulin toxin injection. Even though few patients can be cured with only one treatment and repeat procedure might be needed, long term relief from dysphagia can be obtained in about 90% of cases with either surgical interventions such as laparoscopic Heller myotomy or with endoscopic techniques such pneumatic dilatation or, more recently, with per-oral endoscopic myotomy. Age, sex, and manometric type by HRM are also predictors of responsiveness to treatment. Older patients, females and type II achalasia are better after treatment compared to younger patients, males and type III achalasia. Self-expandable metallic stents are an alternative in patients non responding to conventional therapies.

Submucosal tunnel endoscopy: Peroral endoscopic myotomy and peroral endoscopic tumor resection

Peroral endoscopic myotomy (POEM) is an innovative, minimally invasive, endoscopic treatment for esophageal achalasia and other esophageal motility disorders, emerged from the natural orifice transluminal endoscopic surgery procedures, and since the first human case performed by Inoue in 2008, showed exciting results in international level, with more than 4000 cases globally up to now. POEM showed superior characteristics than the standard 100-year-old surgical or laparoscopic Heller myotomy (LHM), not only for all types of esophageal achalasia [classical (I), vigorous (II), spastic (III), Chicago Classification], but also for advanced sigmoid type achalasia (S1 and S2), failed LHM, or other esophageal motility disorders (diffuse esophageal spasm, nutcracker esophagus or Jackhammer esophagus). POEM starts with a mucosal incision, followed by submucosal tunnel creation crossing the esophagogastric junction (EGJ) and myotomy. Finally the mucosal entry is closed with endoscopic clip placement. POEM permitted relatively free choice of myotomy length and localization. Although it is technically demanding procedure, POEM can be performed safely and achieves very good control of dysphagia and chest pain. Gastroesophageal reflux is the most common troublesome side effect, and is well controllable with proton pump inhibitors. Furthermore, POEM opened the era of submucosal tunnel endoscopy, with many other applications. Based on the same principles with POEM, in combination with new technological developments, such as endoscopic suturing, peroral endoscopic tumor resection (POET), is safely and effectively applied for challenging submucosal esophageal, EGJ and gastric cardia tumors (submucosal tumors), emerged from muscularis propria. POET showed up to know promising results, however, it is restricted to specialized centers. The present article reviews the recent data of POEM and POET and discussed controversial issues that need further study and future perspectives.

Comparison of early outcomes and quality of life after laparoscopic Heller's cardiomyotomy to peroral endoscopic myotomy for treatment of achalasia

BACKGROUND AND AIM

This retrospective cohort study compared clinical outcomes and quality of life after peroral endoscopic myotomy (POEM) against laparoscopic Heller myotomy (LHM) for treatment of achalasia.

METHODS

Patient demographics, operation time, intraoperative blood loss, hospital stay, time to resume diet and analgesic requirement were recorded. Clinical outcomes including recurrence of dysphagia, need for reintervention, and occurrence of gastroesophageal reflux disease (GERD) were recorded.

RESULTS

From 2001 to 2014, 33 patients underwent POEM whereas 23 patients received LHM. Patients LHM had with longer mean operative time (P = 0.02), more blood loss (P = 0.001) and higher requirement for analgesics (P = 0.009) than those treated by POEM. Hospital stay and time to resume diet were similar. Both POEM and LHM achieved similar dysphagia scores at postoperative 4 weeks, 3 months and 6 months. Twenty-six percent of LHM patients and 15.2% of POEM patients sustained gastroesophageal reflux disease (GERD) after treatment (P = 0.311). Six patients required regular proton pump inhibitor three after POEM and three after LHM (P = 0.639). Thirteen percent of LHM patients sustained recurrent dysphagia and one required reintervention. There was no recurrence in the POEM group. Follow-up duration (mean [SD]) for the LHM group was significantly longer (60 [42] months vs 6 [4] months; P = 0.001). There was also no difference in all four aspects of GERD-related quality of life outcomes.

CONCLUSION

Compared to LHM, POEM achieved shorter operative time, less blood loss and pain. POEM is comparable to LHM for treatment of achalasia with similar incidence of GERD after the procedure.

Peroral Endoscopic Myotomy for Treating Achalasia and Esophageal Motility Disorders

Peroral endoscopic myotomy (POEM) is the application of esophageal myotomy to the concept of natural orifice transluminal surgery (NOTES) by utilizing a submucosal tunneling method. Since the first case of POEM was performed for treating achalasia in Japan in 2008, this procedure is being more widely used by many skillful endosopists all over the world. Currently, POEM is a spotlighted, emerging treatment option for achalasia, and the indications for POEM are expanding to include long-standing, sigmoid shaped esophagus in achalasia, even previously failed endoscopic treatment or surgical myotomy, and other spastic esophageal motility disorders. Accumulating data about POEM demonstrate excellent short-term outcomes with minimal risk of major adverse events, and some existing long-term data show the efficacy of POEM to be long lasting. In this review article, we review the technical details and clinical outcomes of POEM, and discuss some considerations of POEM in special situations.

Efficacy of peroral endoscopic myotomy (POEM) in the treatment of achalasia: a systematic review and meta-analysis

BACKGROUND

Peroral endoscopic myotomy (POEM) is an evolving therapeutic modality for achalasia. We aim to determine efficacy of POEM for the treatment of achalasia and compare it with laparoscopic Heller's myotomy (LHM).

MATERIALS AND METHODS

Systematic review and meta-analyses was conducted on 19 studies using POEM for achalasia. Pubmed, Medline, Cochrane, and Ovid databases, were searched using the terms 'achalasia', 'POEM', 'peroral endoscopic myotomy', 'per oral endoscopic myotomy', and 'per-oral endoscopic myotomy'. Reduction in Eckhart's score and lower esophageal sphincter (LES) pressure were the main outcome measures.

RESULTS

A total of 1,045 patients underwent POEM in 29 studies. Ninety patients undergoing POEM was compared with 160 undergoing LHM in five studies. Nineteen and 14 studies, respectively, evaluated for Eckhart's score and LES pressure. There was significant reduction in Eckhart's score and LES pressure with effect sizes of -7.95 (p < 0.0001) and -7.28 (p < 0.0001), respectively. There was significant heterogeneity among the studies [(Q = 83.06; I (2) = 78.33 %; p < 0.0001) for Eckhart's score and (Q = 61.44; I (2) = 75.68 %; p < 0.0001) for LES pressure]. There were no differences between POEM and LHM in reduction in Eckhart's score, post-operative pain scores and analgesic requirements, length of hospital stay, adverse events, and symptomatic gastroesophageal reflux/reflux esophagitis. Operative time was significantly lower for POEM.

CONCLUSIONS

POEM is effective for achalasia and has similar outcomes as LHM. Multicenter randomized trials need to be conducted to further compare the efficacy and safety of POEM between treatment naïve achalasia patients and those who failed treatment.

Intraoperative measurement of esophagogastric junction cross-sectional area by impedance planimetry correlates with clinical outcomes of peroral endoscopic myotomy for achalasia: a multicenter study

BACKGROUND

Peroral endoscopic myotomy (POEM) has been introduced as an endoscopic alternative to surgical myotomy. The endoluminal functional lumen imaging probe (endoFLIP) evaluates esophagogastric junction (EGJ) distensibility based on cross-sectional area and pressure in response to volume distension. The aim of this study was to evaluate whether there is a correlation between endoFLIP measurements during POEM and postoperative clinical outcomes in terms of symptom relief and development of post-procedure reflux.

METHODS

We conducted a retrospective review of achalasia patients who underwent POEM and intraoperative endoFLIP at three tertiary centers. Patients were divided into two groups based on clinical response measured by Eckardt score (ES): good response (ES < 3) or poor response (ES ≥ 3). Post-procedure reflux was defined as the presence of esophagitis and/or abnormal pH study. EGJ diameter, cross-sectional area, and distensibility measured by endoFLIP were compared.

RESULTS

Of the 63 treated patients, 50 had good and 13 had poor clinical response. The intraoperative final EGJ cross-sectional area was significantly higher in the good-response group versus poor-response group; median (interquartile range): 89.0 (78.5-106.7) versus 72.4 (48.8-80.0) mm(2) [p = 0.01]. The final EGJ cross-sectional area was also significantly higher in patients who had reflux esophagitis after POEM: 99.5 (91.2-103.7) versus 79.3 (57.1-94.2) mm(2) [p = 0.02].

CONCLUSION

Intraoperative EGJ cross-sectional area during POEM for achalasia correlated with clinical response and post-procedure reflux. Impedance planimetry is a potentially important tool to guide the extent and adequacy of myotomy during POEM.