Per-oral endoscopic myotomy for achalasia: An American perspective

Is peroral endoscopic myotomy the new gold standard for achalasia therapy?

Our review focuses on critical analysis of the literature to determine whether peroral endoscopic myotomy (POEM) is poised to replace laparoscopic Heller myotomy (LHM) as the new "gold standard" for achalasia therapy. POEM matches or exceeds the efficacy of LHM. The difference in objective gastroesophageal reflux disease (GERD) between POEM and LHM is modest at best and dissipates with time. Post-POEM GERD can be easily managed medically in most patients without long-term GERD sequelae or the need for surgical fundoplication. Emerging POEM technique modifications can further decrease GERD. Endoscopic antireflux procedures such as transoral incisionless fundoplication (TIF) or POEM + F (POEM + fundoplication) can be used in the rare cases of medication-refractory GERD, but their long-term efficacy remains in question. In this comprehensive review, we summarize the current status of POEM with emphasis on GERD evaluation, prevention, treatment, and comparative data vs. LHM. Based on this analysis, it appears that POEM is indeed the new gold standard in the therapy of achalasia.

Safety and Efficacy of the Supine Position with the Right Shoulder Raised versus the Left Lateral Position in Peroral Endoscopic Myotomy for Achalasia: A Large-Sample Retrospective Study

BACKGROUND

The correct surgical position is very important in the treatment of peroral endoscopic myotomy (POEM) for achalasia, which can make the procedure safer and more efficient. Currently, there are two commonly used positions: the supine position with the right shoulder raised and the left lateral position. This study aims to evaluate the differences in the safety and efficacy of these two positions.

METHODS

We conducted a retrospective study of 702 patients with achalasia undergoing POEM from December 2010 to December 2020. These patients were divided into the supine position with the right shoulder raised group (n = 579) and the left lateral position group (n = 123). The efficacy of POEM and adverse events were analyzed.

RESULTS

The clinical characteristics were similar in both groups, and there were no significant differences between the two groups in the Eckardt score change, lower esophageal sphincter (LES) basal pressure or residual pressure after POEM (all p > 0.05). The mean operative time in the supine position with the right shoulder raised group was significantly shorter than that in the left lateral position group (43.5 min vs. 54.6 min, respectively, p < 0.001). In addition, the differences between the two groups in terms of gas-related complications, such as pneumoperitoneum, pneumomediastinum, and subcutaneous emphysema were statistically significant (all p < 0.05).

CONCLUSIONS

The efficacy of POEM was comparable between the two groups. However, the supine position with the right shoulder raised significantly reduced the operative time and the rate of procedure-related adverse events, especially gas-related complications.

Peroral Endoscopic Myotomy for Esophageal Motility Disorders

Peroral endoscopic myotomy (POEM) is one of the most clinically successful tunnel-based minimally invasive endoscopic treatments. The classic indications of POEM include achalasia of all types, including failed prior treatments, and expanded indications include the non-achalasia esophageal motility disorders, such as esophagogastric junction outflow obstruction, diffuse esophageal spasm, and jackhammer esophagus. For achalasia treatment, POEM has achieved a comparable surgical efficacy and a safety outcome and, therefore, has emerged as a first-line treatment. For non-achalasia esophageal motility disorders, POEM has also shown high clinical response rates. The complication rate of POEM for esophageal motility disorders is low and most complications are managed with conservative treatment. Currently, POEM is a representative procedure of natural orifice transluminal endoscopic surgery, which has shown a good clinical efficacy with low complication rates for esophageal motility disorders including achalasia. However, further studies are needed to treat non-achalasia motility disorder via POEM.

Peroral endoscopic myotomy for esophageal motility disorders

BACKGROUND

Esophageal motility disorders which include achalasia, esophagogastric junction outflow obstruction (EGJ outflow obstruction), jackhammer esophagus (JE), distal esophageal spasm (DES), etc. are rare disease of unknown causes. The diagnosis is based on endoscopy, barium meal, and high-resolution manometry (HRM). With the development of endoscopy, peroral endoscopic myotomy (POEM) has emerged as a standard method for the treatment of achalasia.

PURPOSE

The purpose of this article is to enable gastroenterologists to have a more comprehensive understanding of the application status, technical characteristics, clinical efficacy and future prospect of POEM in the treatment of esophageal motility disorders.

METHODS

Through a large number of reading literature, combined with clinical practice, summary and analysis of the indications, procedure, efficacy, complications, and controversies of POEM in the treatment of esophageal motility disorders, as well as the current and future perspectives of POEM were studied.

RESULTS

POEM is safe and effective in the treatment of esophageal motility disorders, but the GERD reflux rate is higher.

CONCLUSIONS

POEM can be a new option for the treatment of esophageal movement disorders, but large sample, multi-center, long-term study reports are needed, and it promotes the development of NOTES technology.

Updated Systematic Review of Achalasia, with a Focus on POEM Therapy

AIM

To systematically review clinical presentation, diagnosis, and therapy of achalasia, focusing on recent developments in high-resolution esophageal manometry (HREM) for diagnosis and peroral endoscopic myotomy (POEM) for therapy.

METHODS

Systematic review of achalasia using computerized literature search via PubMed and Ovid of articles published since 2005 with keywords ("achalasia") AND ("high resolution" or "HREM" or "peroral endoscopic myotomy" or "POEM"). Two authors independently performed literature searches and incorporated articles into this review by consensus according to prospectively determined criteria.

RESULTS

Achalasia is an uncommon esophageal motility disorder, usually manifested by dysphagia to solids and liquids, and sometimes manifested by chest pain, regurgitation, and weight loss. Symptoms often suggest more common disorders, such as gastroesophageal reflux disease (GERD), thus often delaying diagnosis. Achalasia is a predominantly idiopathic chronic disease. Diagnosis is typically suggested by barium swallow showing esophageal dilation; absent distal esophageal peristalsis; smoothly tapered narrowing ("bird's beak") at esophagogastric junction; and delayed passage of contrast into stomach. Diagnostic findings at high-resolution esophageal manometry (HREM) include: distal esophageal aperistalsis and integrated relaxation pressure (trough LES pressure during 4 s) > 15 mmHg. Achalasia is classified by HREM into: type 1 classic; type 2 compartmentalized high pressure in esophageal body, and type 3 spastic. This classification impacts therapeutic decisions. Esophagogastroduodenoscopy is required before therapy to assess esophagus and esophagogastric junction and to exclude distal esophageal malignancy. POEM is a revolutionizing achalasia therapy. POEM creates a myotomy via interventional endoscopy. Numerous studies demonstrate that POEM produces comparable, if not superior, results compared to standard laparoscopic Heller myotomy (LHM), as determined by LES pressure, dysphagia frequency, Eckardt score, hospital length of stay, therapy durability, and incidence of GERD. Other therapies, including botulinum toxin injection and pneumatic dilation, have moderately less efficacy and much less durability than POEM.

CONCLUSION

This comprehensive review suggests that POEM is equivalent or perhaps superior to LHM for achalasia in terms of cost efficiency, hospital length of stay, and relief of dysphagia, with comparable side effects. The data are, however, not conclusive due to sparse long-term follow-up and lack of randomized comparative clinical trials. POEM therapy is currently limited by a shortage of trained endoscopists.

Safety and efficacy of using a short tunnel versus a standard tunnel for peroral endoscopic myotomy for Ling type IIc and III achalasia: a retrospective study

BACKGROUND AND AIMS

Peroral endoscopic myotomy (POEM) for patients with Ling type IIc and III achalasia is associated with a high rate of adverse events. Decreasing the lengths of the tunnel and myotomy may be an effective method for reducing this rate. This study aimed to assess the safety and efficacy of using a short tunnel versus a standard tunnel for POEM.

METHOD

We conducted a retrospective study of 126 patients with Ling type IIc and III achalasia undergoing POEM from January 2013 to December 2016. These patients were divided into a short tunnel group (n = 63) and a standard tunnel group (n = 63). The clinical efficacy of the procedure, operative time, length of the tunnel, length of myotomy and rates of adverse events were analyzed.

RESULTS

The preoperative features were similar in both groups. No significant differences were found between the two groups in Eckardt score change, lower esophageal sphincter (LES) basal pressure or residual pressure after POEM (all p > 0.05). The mean lengths of the tunnel and myotomy were 7.6 cm and 4.8 cm, respectively, in the short tunnel group and 11.8 cm and 9.2 cm, respectively, in the standard tunnel group. The mean operative time of the short tunnel group was significantly shorter than that of the standard tunnel group (39.5 min vs. 48.2 min, respectively, p = 0.001). A significant difference was observed in the rates of procedure-related adverse events between the two groups (9.5% vs. 33.3%, p = 0.001).

CONCLUSION

The efficacy of the procedure was comparable between the two groups. However, the short tunnel significantly reduced the operation time and the rates of procedure-related adverse events.

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.

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.).

Ling classification applied in the preoperative safety and effectiveness assessment of POEM

BACKGROUND AND STUDY AIMS

At present, peroral endoscopic myotomy (POEM) has been considered as the recommended treatment for achalasia, as it causes trauma to a smaller area and has fewer short-term serious complications than other treatments. However, due to the different morphology of esophagus, not all the patients with achalasia are eligible to receive POEM surgery. And the purpose of our study was to apply Ling classification, which proser Linghu put forward in 2011, in the preoperative assessment of POEM, expecting to reduce the occurrence rate of complications during or post-POEM.

PATIENTS AND METHODS

The clinical data of 341 achalasia patients were collected and classified, according to the endoscopic pictures related to the middle and the lower parts of the esophagus. The correlation between Ling classification and LESP or Eckardt score was analyzed for the efficiency estimation, and the correlation of Ling classification and incidence of complications was counted for the safety evaluation.

RESULTS

Ling classification was correlated with the LESP of 95 patients and Eckardt score of 131 patients. Compared to preoperative data, post-POEM LESP and Eckardt score both decreased significantly in all types of Ling classification (p < 0.05), while no significant difference in the decrease degree of either LESP or Eckardt score was found among different types of Ling classification (p > 0.05). This means Ling classification may not directly affect the postoperative efficacy of POEM. By analyzing the correlation between Ling classification and intraoperative complications, we found that the differences of total complications, gas-related complication and mucosal injury were all significant among all types of Ling classification (p < 0.05).

CONCLUSIONS

Ling classification can be applied in the preoperative assessment of the safety and efficacy of POEM, and it might provide a guideline for how to reduce the complications during POEM surgery.

Per Oral Endoscopic Myotomy in Children with Achalasia Cardia

BACKGROUND/AIMS

Achalasia cardia (AC) is a motility disorder, characterized by impaired lower esophageal sphincter relaxation and absence of esophageal peristalsis. AC is rare in children with unclear optimum management strategies. Per oral endoscopic myotomy (POEM) is a novel technique for management of achalasia with encouraging results in adult patients. The efficacy and safety of POEM is not known for pediatric AC. The aim of our study was to evaluate the safety and efficacy of POEM in children with achalasia cardia.

METHODS

The data of all children (< 18 years) who underwent POEM at our center was retrospectively analysed. Symptoms were analysed using a validated score (Eckardt score) at regular predefined intervals. Objective parameters including high-resolution manometry, timed barium swallow and esophagogastroduodenoscopy were assessed before the procedure and at 1-year follow-up. Clinical success was defined as an Eckardt score ≤ 3.

RESULTS

A total of 15 children underwent POEM during the specified period. Ten out of 15 (10/15) completed 1-year follow-up. Median operative time was 100 (38-240) minutes. Mean pre and post procedure LES pressure were 36.64 ± 11.08 mmHg and 15.65 ± 5.73 mmHg, respectively (P = 0.001). Mean Eckardt score before and after the POEM was 7.32 ± 1.42 and 1.74 ± 0.67, respectively (P = 0.001). Mean percentage improvement in barium emptying at 5 minutes was 63.70 ± 4.46%. All children had complete resolution of symptoms at 1 year. Median weight gain of children at 1 year was 0.65 kg (range, 0.0-4.6).

CONCLUSIONS

POEM is safe and effective for children and adolescents with achalasia. Future trials with larger sample size are warranted to establish its efficacy in pediatric AC.

Chicago Classification of Esophageal Motility Disorders: Applications and Limits in Adults and Pediatric Patients with Esophageal Symptoms

The Chicago classification (CC) is most valued for its systematic approach to esophageal disorders and great impact in unifying practice for esophageal manometric studies. In view of the ever-growing wealth of knowledge and experience gained by the expanding use of high-resolution manometry (HRM) in various clinical scenarios, the CC is regularly updated. Its clinical impact and ability to predict clinical outcome, both in adults and pediatrics, will be further promoted by recognizing its current limitations, incorporating new metrics in its diagnostic algorithms and adjusting the HRM protocols based on the clinical question posed. Herein, we discuss the current limitations of the CC and highlight some areas of improvement for the future.

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).

A New Method for Endoscopic Sampling of Submucosal Tissue in the Gastrointestinal Tract: A Comparison of the Biopsy Forceps and a New Drill Instrument

Background Sampling of submucosal lesions in the gastrointestinal tract through a flexible endoscope is a well-recognized clinical problem. One technique often used is endoscopic ultrasound-guided fine-needle aspiration, but it does not provide solid tissue biopsies with preserved architecture for histopathological evaluation. To obtain solid tissue biopsies from submucosal lesions, we have constructed a new endoscopic biopsy tool and compared it in a crossover study with the standard double cupped forceps. Methods Ten patients with endoscopically verified submucosal lesions were sampled. The endoscopist selected the position for the biopsies and used the instrument selected by randomization. After a biopsy was harvested, the endoscopist chose the next site for a biopsy and again used the instrument picked by randomization. A total of 6 biopsies, 3 with the forceps and 3 with the drill instrument, were collected in every patient. Results The drill instrument resulted in larger total size biopsies (mm²; Mann-Whitney U test, P = .048) and larger submucosal part (%) of the biopsies (Mann-Whitney U test, P = .003) than the forceps. Two patients were observed because of chest pain and suspicion of bleeding in 24 hours. No therapeutic measures were necessary to be taken. Conclusion The new drill instrument for flexible endoscopy can safely deliver submucosal tissue samples from submucosal lesions in the upper gastrointestinal tract.

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.

Gastroesophageal reflux disease after peroral endoscopic myotomy: Analysis of clinical, procedural and functional factors, associated with gastroesophageal reflux disease and esophagitis

BACKGROUND AND AIM

Peroral endoscopic myotomy (POEM) does not include any antireflux procedure, resulting in a certain risk of iatrogenic gastroesophageal reflux disease (GERD). The aim of the present study was to evaluate the incidence of iatrogenic GERD after POEM and identify preoperative, perioperative and postoperative factors associated with GERD.

METHODS

All patients treated at a single center who had a complete GERD evaluation after POEM were included in the study. Demographics, preoperative and follow-up data, results of functional studies and procedural data were collected and analyzed.

RESULTS

A total of 103 patients (mean age 46.6 years, 47 males) were included. Postoperative altered esophageal acid exposure was attested in 52 patients (50.5%). A total of 19 patients (18.4%) had heartburn and 21 had esophagitis (20.4%). Overall, a clinically relevant GERD (altered esophageal acid exposure, associated with heartburn and/or esophagitis) was diagnosed in 30 patients (29.1%). Correlation between the severity of esophageal acid exposure with heartburn and esophagitis after POEM was found. Patients with heartburn had a lower postoperative 4-second integrated relaxation pressure compared to patients without symptoms (7.6 ± 3.8 mmHg vs 10.01 ± 4.4 mmHg, p<0.05). No correlations were identified with patient sex, age, postoperative body mass index, esophageal shape (sigmoid vs non sigmoid), lower esophageal sphincter pressure, length of myotomy, previous therapies and type of achalasia at high-resolution manometry.

CONCLUSIONS

Preoperative, perioperative or postoperative factors minimally correlated with GERD after POEM. Clinically relevant GERD was identified in less than one-third of patients, but all patients were well controlled with medical therapy.

Peroral endoscopic myotomy for achalasia cardia: Treatment analysis and follow up of over 200 consecutive patients at a single center

BACKGROUND AND AIM

Peroral endoscopic myotomy (POEM) is a recently introduced technique for the treatment of achalasia cardia (AC). Data regarding safety and efficacy are still emerging. We report our experience of POEM emphasizing its safety, efficacy and follow-up data.

METHODS

Patients with AC (220; mean age 39 years, range 9-74 years) underwent POEM from January 2013 to August 2014 for AC. Retrospective analysis of prospectively collected data was done. POEM was carried out by the standard technique of mucosal incision, submucosal tunneling, and myotomy of the esophageal and gastric muscle bundles followed by closure of the mucosal incision by hemoclips. Eckardt score, high-resolution manometry (HRM) and timed barium esophagogram (TBE) were used to evaluate the results. Post-procedure patients were followed up.

RESULTS

Technical success rate of POEM was 96%. At 1 year, clinical success rate was 92%. Mean Eckardt score was 7.2 ± 1.55 prior to POEM and 1.18 ± 0.74 after POEM (P = 0.001). There was significant improvement of esophageal emptying on TBE (38.4 ± 14.0 % vs 71.5 ± 16.1 % (P = 0.001). Pre-procedure and post-procedure mean lower esophageal sphincter pressure was 37.5 ± 14.5 mmHg and 15.2 ± 6.3 mmHg, respectively. (P = 0.001) Erosive esophagitis was seen in 16% of patients who underwent POEM. There were no major adverse events.

CONCLUSIONS

Study demonstrates excellent safety profile of POEM with significant relief of symptoms, reduced pressure at HRM and improved emptying at TBE. Further prospective studies are required to compare with other treatment modalities.

Risk of infection after iatrogenic perforation of the gut wall? Evaluation of preventive strategies in a randomized controlled animal trial

BACKGROUND

Interventional endoscopies entail a risk of infection secondary to perforation of the luminal wall. Thereby, bacteria may be introduced into the sterile environment of the peritoneal cavity (PC). Limited data are available regarding the efficacy of prophylactic anti-infective treatments. The aim of the study was to examine the efficacy/safety of anti-infective means in the prevention of infection by interventional endoscopies in a randomized controlled animal trial.

METHODS

Forty pigs were randomized to: 1: control; 2: oral lavage; 3: gastric lavage; 4: oral/gastric lavage; 5: i.m. antibiotics. Lavage was performed with Octenisept prior to the operation. After gastric wall perforation, peritoneoscopy was performed. Before the procedure, after closure and prior to autopsy, intraabdominal lavage for bacterial culture was taken using mini-laparoscopy. At autopsy, macroscopic appearance of the PC was scored. Lavage fluids were grown to identify/quantify bacterial load. Concentration of intraperitoneal bacteria at autopsy was defined as main outcome parameter.

RESULTS

No major complications occurred in any of the procedures. Bacterial load of the PC at autopsy was significantly reduced with antibiotics compared to all other groups, whereas it did not differ between the lavage groups and control. Macroscopic scoring of the PC showed significant lower rate of intraabdominal abscesses in the antibiotic group compared to the lavage groups and control (p < 0.01).

CONCLUSION

Only antibiotic prophylaxis is effective for the prevention of infection after iatrogenic perforation of the gastrointestinal wall. There was no difference between any form of lavage and the control group. Further studies in humans are required to prove these animal data.

Peroral endoscopic myotomy: An emerging minimally invasive procedure for achalasia

Peroral endoscopic myotomy (POEM) is an emerging minimally invasive procedure for the treatment of achalasia. Due to the improvements in endoscopic technology and techniques, this procedure allows for submucosal tunneling to safely endoscopically create a myotomy across the hypertensive lower esophageal sphincter. In the hands of skilled operators and experienced centers, the most common complications of this procedure are related to insufflation and accumulation of gas in the chest and abdominal cavities with relatively low risks of devastating complications such as perforation or delayed bleeding. Several centers worldwide have demonstrated the feasibility of this procedure in not only early achalasia but also other indications such as redo myotomy, sigmoid esophagus and spastic esophagus. Short-term outcomes have showed great clinical efficacy comparable to laparoscopic Heller myotomy (LHM). Concerns related to postoperative gastroesophageal reflux remain, however several groups have demonstrated comparable clinical and objective measures of reflux to LHM. Although long-term outcomes are necessary to better understand durability of the procedure, POEM appears to be a promising new procedure.

Pneumomediastinum and pneumoperitoneum on computed tomography after peroral endoscopic myotomy (POEM): postoperative changes or complications?

BACKGROUND

Many of the acute alterations after peroral endoscopic myotomy (POEM) may be of little clinical significance, while others may herald major clinical problems. The question whether pneumomediastinum/pneumoperitoneum is a normal postoperative finding after POEM, or should be regarded as a sign of a complication needs to be evaluated. Familiarity with these findings in computed tomography (CT) is essential for radiologists.

PURPOSE

To evaluate whether or not pneumomediastinum/pneumoperitoneum detected by chest CT is a sign of a complication after POEM using CO2 insufflation for esophageal achalasia.

MATERIAL AND METHODS

One hundred and eight patients with esophageal achalasia who underwent chest CT within 30 hours after POEM were included. CT findings were retrospectively reviewed by two radiologists in consensus. The correlation between pneumomediastinum and/or pneumoperitoneum shown on CT and the development of complications was analyzed.

RESULTS

Abnormal findings were identified on post-treatment CT, including pneumomediastinum and/or pneumoperitoneum (53.7%, 58/108), pneumothorax (0.9%, 1/108), subcutaneous emphysema (29.6%, 32/108), pleural effusion (69.4%, 75/108), segmental atelectasis of lung tissue (29.6%, 32/108), minor inflammation of lungs (69.4%, 75/108), and ascites (0.9%, 1/108). Pneumomediastinum and pneumoperitoneum were observed simultaneously in 29 cases. The incidence rate of mild complications was high (79.6%, 86/108), while the rate of severe complications was low (2.8%, 3/108). There was no significant correlation between the occurrence of pneumomediastinum and/or pneumoperitoneum on CT and the development of complications (P = 0.542), or the development of severe complications including delayed hemorrhage, esophageal perforation, and retroperitoneal abscess.

CONCLUSION

Pneumomediastinum and pneumoperitoneum detected by CT occur frequently after POEM and may be regarded as normal postoperative changes.

Evaluation of anesthesia management, feasibility and efficacy of peroral endoscopic myotomy (POEM) for achalasia performed in the endoscopy unit

INTRODUCTION

Data on anesthesia management and outcomes associated with peroral endoscopic myotomy (POEM) performed exclusively in the endoscopy unit are limited. In this prospective study, we evaluated the safety of anesthesia management, and the feasibility and efficacy of POEM performed exclusively in the endoscopy unit.

METHODS

A single-center prospective study of consecutive patients with achalasia treated with POEM in an endoscopy unit was performed. Safety of anesthesia management and POEM were determined by procedure-related adverse events. Feasibility was assessed by completion rate. Short-term efficacy was established by clinical success (Eckardt score ≤ 3) and by comparing Eckardt and dysphagia scores before and after POEM.

RESULTS

Patients (n = 52) underwent POEM under general anesthesia with endotracheal intubation and positive pressure ventilation. Aspiration was prevented by keeping patients on a clear liquid diet before the procedure without requiring a prior esophagogastroduodenoscopy for esophageal content clearance. POEM completion rate was 96 % (50/52 patients). There was no post-POEM bleeding. Postprocedure leak was observed in one patient (3 %). Four patients (7.7 %) experienced mucosal injury, three of them were treated uneventfully endoscopically and one required laparoscopic repair. Clinical success was achieved in 88 % of patients. There was a significant decrease in the mean Eckardt score (8.1 to 1.4) and dysphagia score (2.4 to 0.4) (P < 0.0001) at the one month follow up after POEM.

CONCLUSION

Anesthesia management of POEM is safe in the endoscopy unit and aspiration can be prevented without requiring prior esophagogastroduodenoscopy for esophageal content clearance. Overall, POEM performed by a gastroenterologist in the endoscopy unit was feasible and effective for the treatment of achalasia.

Peroral endoscopic myotomy: an evolving treatment for achalasia

Peroral endoscopic myotomy (POEM) was first performed in Japan in 2008 for uncomplicated achalasia. With excellent results, it was adopted by highly skilled endoscopists around the world and the indications for POEM were expanded to include advanced sigmoid achalasia, failed surgical myotomy, patients with previous endoscopic treatments and even other spastic oesophageal motility disorders. With increased uptake and performance of POEM, variations in technique and improved management of adverse events have been developed. Now, 6 years since the first case and with >3,000 procedures performed worldwide, long-term data has shown the efficacy of POEM to be long-lasting. A growing body of literature also exists pertaining to the learning curve, application of novel technologies, extended indications and physiologic changes with POEM. Ultimately, this once experimental procedure is evolving towards becoming the preferred treatment for achalasia and other spastic oesophageal motility disorders.

Recent advancement of therapeutic endoscopy in the esophageal benign diseases

Over the past 30 years, the field of endoscopy has witnessed several advances. With the advent of endoscopic mucosal resection, removal of large mucosal lesions have become possible. Thereafter, endoscopic submucosal resection was refined, permitting en bloc removal of large superficial neoplasms. Such techniques have facilitated the development of antireflux mucosectomy, a promising novel treatment for gastroesophageal reflux. The introduction and use of over the scope clips has allowed for endoscopic closure of defects in the gastrointestinal tract, which were traditionally treated with surgical intervention. With the development of per-oral endoscopic myotomy (POEM), the treatment of achalasia and spastic disorders of the esophagus have been revolutionized. From the submucosal tunnelling technique developed for POEM, Per oral endoscopic tumor resection of subepithelial tumors was made possible. Simultaneously, advances in biotechnology have expanded esophageal stenting capabilities with the introduction of fully covered metal and plastic stents, as well as biodegradable stents. Once deemed a primarily diagnostic tool, endoscopy has quickly transcended to a minimally invasive intervention and therapeutic tool. These techniques are reviewed with regards to their application to benign disease of the esophagus.

The light at the end of the tunnel: a single-operator learning curve analysis for per oral endoscopic myotomy

BACKGROUND

Per oral endoscopic myotomy (POEM) represents a natural orifice transluminal endoscopic surgery approach to Heller myotomy. Our center was the first to offer POEM outside of Japan, allowing us to accumulate what is likely the highest single-operator POEM volume in the United States.

OBJECTIVE

To define the POEM learning curve of a gastroenterologist by using a larger data set and more detailed statistical analysis than used in 2 other reports of POEM performed by surgeons.

DESIGN

Prospective cohort study.

SETTING

Tertiary-care academic medical center.

PATIENTS

We analyzed the first 93 consecutive POEMs on patients with achalasia aged >18 years without contraindications to POEM performed by a single operator from October 2009 to November 2013.

INTERVENTIONS

(1) Efficiency estimation via cumulative sum (CUSUM) analysis, (2) mastery estimation via penalized basis-spline regression and CUSUM analysis, (3) correlation of operator experience with clinical outcomes (Eckardt score improvement, lower esophageal sphincter pressure reduction) and technical errors (accidental mucosotomy rate), and (4) unadjusted and adjusted regression analysis to assess how patient characteristics affected procedure time by using a generalized linear model.

MAIN OUTCOME MEASUREMENTS

Clinical outcomes, procedure time, technical errors.

RESULTS

Efficiency was attained after 40 POEMs and mastery after 60 POEMs. When we used the adjusted regression analysis, only case number (operator experience) significantly affected procedure time (P < .0001). Improvements in clinical outcomes were excellent but not significantly affected by operator experience, as was the case with accidental mucosotomies. Procedure time was not significantly affected by age, sex, achalasia stage, baseline lower esophageal sphincter pressure, baseline Eckardt score, prior treatment of achalasia, prior botulinum toxin injection, incidence of accidental mucosotomies, length of myotomy, or type of knife used (all P > .05).

LIMITATIONS

Our analysis may underestimate the number of POEMs required to achieve mastery for operators with limited or no endoscopic submucosal dissection experience.

CONCLUSION

These results offer thresholds for efficiency and mastery of a single gastroenterologist operator that may guide the efforts of novice POEM operators.

Natural-orifice transluminal endoscopic surgery

BACKGROUND

Natural-orifice transluminal endoscopic surgery (NOTES) represents one of the most significant innovations in surgery to emerge since the advent of laparoscopy. A decade of progress with this approach has now been catalogued, and yet its clinical application remains controversial.

METHODS

A PubMed search was carried out for articles describing NOTES in both the preclinical and the clinical setting. Public perceptions and expert opinion regarding NOTES in the published literature were analysed carefully.

RESULTS

Two hundred relevant articles on NOTES were studied and the outcomes reviewed. A division between direct- and indirect-target NOTES was established. The areas with the most promising clinical application included direct-target NOTES, such as transanal total mesorectal excision and peroral endoscopic myotomy. The clinical experience with distant-target NOTES, such as for appendicectomy and cholecystectomy, showed feasibility; however, NOTES-specific morbidity was introduced and this represents an important limitation.

CONCLUSION

NOTES experimentation in the preclinical setting has increased substantially. There has also been a significant increase in the application of NOTES in humans in the past decade. Enthusiasm for NOTES should be tempered by the risk of incurring NOTES-specific morbidity. Surgeons should carefully consider patient preferences regarding this new minimally invasive option, as opinions are not unanimously supportive of NOTES. As technical limitations are overcome, the clinical application of NOTES is predicted to increase. It is paramount that, when this complex technique is performed on humans, it is applied judiciously by appropriately trained experts with outcomes recorded in a registry.

Self-expandable metal stents for achalasia: Thinking out of the box!

Achalasia is a primary motor disorder of the esophagus diagnosed manometrically in the clinical setting of dysphagia to both solids and liquids. Currently established treatment options include pneumatic dilation, laparoscopic Heller myotomy, botulinum toxin injection performed endoscopically, oral agents that relax the lower esophageal sphincter and esophagectomy for refractory, end-stage disease. Despite their effectiveness, a significant proportion of patients eventually relapses and needs retreatment. In this setting, several new techniques are under investigation promising future enrichment of our therapeutic armamentarium for achalasic patients. Among them, peroral endoscopic myotomy and self-expandable metal stents placed across the gastro-esophageal junction represent the most encouraging modalities, as initial studies assessing their efficacy and safety indicate. This review highlights the role of self-expandable metal stents in the management of patients with achalasia. Their possible position in the therapeutic algorithm of achalasia along with established and novel techniques is also assessed. Finally, the need for large prospective randomized trials is underlined in order to elucidate the numerous relevant issues.

Per-oral endoscopic myotomy: Major advance in achalasia treatment and in endoscopic surgery

Per-oral endoscopic myotomy (POEM) represents a natural orifice endoscopic surgery (NOTES) approach to laparoscopy Heller myotomy (LHM). POEM is arguably the most successful clinical application of NOTES. The growth of POEM from a single center in 2008 to approximately 60 centers worldwide in 2014 with several thousand procedures having been performed attests to the success of POEM. Initial efficacy, safety and acid reflux data suggest at least equivalence of POEM to LHM, the previous gold standard for achalasia therapy. Adjunctive techniques used in the West include impedance planimetry for real-time intraprocedural luminal assessment and endoscopic suturing for challenging mucosal defect closures during POEM. The impact of POEM extends beyond the realm of esophageal motility disorders as it is rapidly popularizing endoscopic submucosal dissection in the West and spawning offshoots that use the submucosal tunnel technique for a host of new indications ranging from resection of tumors to pyloromyotomy for gastroparesis.

Submucosal endoscopy: the new frontier of therapeutic endoscopy

PURPOSE OF REVIEW

Peroral endoscopic myotomy (POEM) and submucosal tunneling and endoscopic resection (STER) have been recently described as minimally invasive therapies for achalasia and gastrointestinal subepithelial tumors originating from the muscularis propria, respectively. This review illustrates the latest developments in the field of submucosal endoscopy, focuses on POEM and sheds light on STER.

RECENT FINDINGS

Multiple studies from the United States, Asia and Europe have shown that POEM is an effective and safe procedure for achalasia when performed by experienced operators with adequate clinical response in 80-90% of patients. Nonetheless, POEM requires a demanding skill set that involves both advanced endoscopic skills and knowledge of surgical anatomy. In addition, the endoscopist must have the capability to manage procedural complications. Similarly, STER appears to be an effective therapy for treatment of small and medium sized gastrointestinal tumors originating from the muscularis propria.

SUMMARY

POEM and STER offer minimally invasive and effective treatment alternatives for patients with achalasia, spastic esophageal disorders and upper gastrointestinal tumors originating from the muscularis propria.

Peroral endoscopic myotomy for achalasia: Analysis of 58 cases

AIM: To assess the safety, feasibility and clinical efficacy of peroral endoscopic myotomy (POEM) in the treatment of achalasia.

METHODS: Clinical data of 58 patients with AC who underwent POEM in our department from May 2011 to June 2013 were analyzed retrospectively. Intraoperative and postoperative complications, symptoms of dysphagia (subjective symptom score and Eckardt score), height of barium (cm) at 1, 2 and 5 min, and recurrence rate and the incidence of reflux evaluated by gastrointestinal endoscopy at 3, 6, 12, and 24 mo follow-ups were analyzed.

RESULTS: All the 58 patients underwent POEM successfully. A small amount of subcutaneous emphysema was observed in only 1 case, and there were no mediastinal emphysema, pneumothorax, pneumoperitoneum or other complications. The estimated average blood loss was < 10 mL, and no serious postoperative complications such as delayed bleeding, perforation and empyema occurred. Mean comprehensive subjective symptom score decreased from 10 to 0.8 following the procedure, and there were significant differences (P < 0.01) between pre and postoperative barium height and Eckardt score. During postoperative follow-up, there appeared an improvement in the life quality of patients. Approximately 75% (43/58) of patients gained weight by an average of 3.7 kg (1-7 kg). Two patients had reflux symptoms, and endoscopy suggested esophagitis (modified Los classification LA-A in one case LA-B in the other). Esophageal 24-h pH monitoring showed that prompt esophageal acid exposure time (more than 4.5% of the time pH value < 4) was 13.4%, of which 5.7% occurred in the standing position and 26.1% in the supine position, and the symptoms in all such patients were easily controlled by the usual dosage of proton pump inhibitors (PPI). During the follow-up, two patients experienced eating choking symptoms at 3 and 6 mo, respectively, and after single endoscopic balloon dilatation (EPD), Eckardt scores became 0, and the dysphagia relieved with no reflux.

CONCLUSION: POEM is safe, minimally invasive and effective in the management of achalasia.