Several studies have hypothesized that sparing the oblique/sling fibers during posterior peroral endoscopic myotomy (POEM) may reduce the incidence of gastroesophageal reflux disease (GERD) and reflux esophagitis without compromising the established safety and efficacy of the procedure. This study compares perioperative, postoperative motility-related, and postoperative GERD-related outcomes between posterior oblique/sling fibers-sparing POEM (OFS-POEM) and conventional posterior POEM through a pairwise meta-analysis of comparative studies.

We conducted a systematic literature review following PRISMA guidelines to identify articles directly comparing posterior OFS-POEM with conventional posterior POEM. A pairwise meta-analysis was performed using a random-effects model. Effect sizes were calculated as odds ratios for dichotomous data and mean differences for continuous data.

No significant differences were observed in perioperative outcomes, including mean gastric myotomy length, mean operative time, and incidence of adverse events. Similarly, no significant differences were noted in postoperative motility-related outcomes, such as mean Eckardt score and mean integrated relaxation pressure. However, a statistically significant reduction in the incidence of symptomatic GERD was observed in favor of OFS-POEM, with a number needed to treat (NNT) of 10 (95% CI: 6-49). Interestingly, no significant differences were found in the incidence of objectively diagnosed postoperative GERD, such as the number of patients with DeMeester scores >14 or the incidence of reflux esophagitis.

This study suggests that OFS-POEM may reduce the incidence of symptomatic GERD following POEM, without affecting the incidence of GERD diagnosed by pH studies (DeMeester score >14) or by endoscopy (reflux esophagitis). Future studies with larger sample sizes are needed to further investigate the impact of OFS-POEM on GERD incidence as determined by pH studies and endoscopic findings. Given the limitations of this study, no definitive conclusions can be drawn. Multicenter randomized controlled trials with larger sample sizes are required to reach more reliable conclusions. Furthermore, stratifying data according to the type and class of achalasia would provide valuable information on whether there are differences in outcomes among the various types and classes of achalasia.

Background: Shortening the myotomy length during peroral endoscopic myotomy (POEM) for achalasia has been hypothesized to reduce gastroesophageal reflux disease (GERD) incidence while maintaining procedural efficacy. This meta-analysis compares the outcomes of short POEM (S-POEM) and long POEM (L-POEM). Methods: A systematic review adhering to PRISMA guidelines identified studies directly comparing S-POEM and L-POEM. Study quality was assessed using the Risk of Bias in Non-randomized Studies of Interventions and Revised Cochrane Risk of Bias for Randomized Trials tools. A pairwise meta-analysis was conducted using the random-effects model. Results: In perioperative outcomes, S-POEM significantly reduced operative time and required fewer clips compared with L-POEM, with no significant differences in adverse events or length of stay. Regarding GERD-related outcomes, S-POEM demonstrated a statistically significant reduction in abnormal esophageal acid exposure on 24-hour pH-impedance testing, with a number needed to treat of 10. While the reduction in symptomatic GERD did not reach statistical significance (P = .06), the P value was very close to the threshold for significance (.05), and all seven included studies reported decreased symptomatic GERD with S-POEM. This is therefore considered a noteworthy finding. The rates of esophagitis and lower esophageal sphincter pressure did not differ significantly between the groups. Efficacy-related outcomes, including clinical success, Eckardt score, and barium height at 5 minutes, were comparable between S-POEM and L-POEM. However, integrated relaxation pressure was significantly higher in the S-POEM group. Conclusions: This study suggests that shortening the myotomy length may reduce GERD incidence following POEM without compromising its efficacy in achalasia treatment. In addition, a shorter myotomy length decreases operative time, potentially reducing time-related costs and improving workflow.

Per oral endoscopic myotomy (POEM) is rapidly emerging as the treatment of choice for achalasia cardia, but its success is marred by problematic reflux. Although symptomatic reflux rates are low and often comparable to that after laparoscopic Hellers myotomy (LHM), a high incidence of pathologic reflux has been noted after POEM. This poses a dilemma as to what is true reflux, and in determining the indications and optimal endpoints for managing post-POEM reflux. The two pertinent reasons for the difference in reflux rates between LHM and POEM are the variation in length and location of myotomy and the absence of an anti-reflux procedure in POEM. Proton pump inhibitor remains the most sought-after treatment of POEM derived reflux. Nevertheless, modifications in the procedural technique of POEM and the addition of endoscopic fundoplication can probably emerge as a game changer. This article briefly reviews the incidence, causes, controversies, predictive factors, and management strategies related to post-POEM reflux.

The purpose of this study was to assess the 5-year impact of a per oral endoscopic myotomy (POEM) program on both clinical and financial outcomes for our hospital system and the rural community we serve.

We evaluated the clinical and financial outcomes of all patients who underwent POEM for achalasia. Patients were also contacted by phone to complete the Gastroesophageal Reflux Disease-Health Related Quality of Life (GERD-HRQL) questionnaire postoperatively. Financial data for all robot-assisted laparoscopic Heller myotomy patients from our institution during the same period were also obtained for cost comparison.

A total of 107 patients underwent POEM in the first 5 years following program implementation, with a mean age of 61.4 ± 17.9 years. There were 75 patients (70%) who participated in the GERD-HRQL survey at a mean follow-up of 84 weeks (range, 6 to 244 weeks). There were 88.2% of respondents who reported no or minimal dysphagia symptoms, and 93.4% of respondents reported no or minimal reflux symptoms. On postoperative upper endoscopy, 19.1% of patients had esophagitis. Implementation of the POEM program resulted in a substantial increase in case volume, growing from 5 myotomy cases per year to 24 myotomy cases per year after 2017. Cost analysis demonstrated a significantly lower index encounter cost for POEM compared with robot-assisted laparoscopic Heller myotomy of approximately $6,000.

This study demonstrates the effectiveness and positive financial impact for both our community and hospital system following implementation of a POEM program at a tertiary medical center serving a large, rural population.

This is a comprehensive review of intraoperative, early postoperative, and late postoperative complications of Per Oral Endoscopic Myotomy with a focus on prevention, intraoperative management, and postoperative management.

There are few data favoring the need for septotomy at the time of peroral endoscopic myotomy (POEM) or if POEM alone is sufficient. Our aim was to compare POEM outcomes with and without septotomy (POEM+S or POEM-S) in patients with symptomatic epiphrenic diverticula (ED) and an underlying motility disorder.

This was an international, multicenter retrospective study involving 21 centers between January 2014 and January 2023. Patients with ED and an underlying motility disorder who underwent POEM were included. The primary outcome was clinical success (Eckardt score [ES] ≤3 or a 1-point drop in ES for patients with baseline ES <3) without the need for repeat surgical/endoscopic interventions during follow-up.

A total of 85 patients (mean age, 64.29 ± 17.1 years; 32 [37.6%] female) with ED and underlying motility disorder underwent POEM+S (n = 47) or POEM-S (n = 38). Patients in the POEM+S group had a significantly higher mean pre-POEM ES (7.3 ± 2.1 vs 5.8 ± 2; P = .002). The most common indication for POEM was achalasia (51% in the POEM+S cohort and 51.8% in the POEM-S cohort; P = .7). A posterior approach was favored in the POEM+S group (76.6% vs 52.6%; P = .02). A similar rate of technical success was seen in both groups (97.9% vs 100%; P = .1). The rate of adverse events was similar between the 2 cohorts (4.2% vs 8.1%; P = .6). The median length of hospital stay after POEM-S was significantly longer compared with POEM+S (2 days [interquartile range (IQR), 1-4 days] vs 1 day [IQR, 1-2 days]; P = .005). Clinical success was equivalent between the 2 groups (83% vs 86.8%; P = .6) at a median follow-up duration of 8 months (IQR, 3-19 months).

In patients with ED and an underlying motility disorder, both POEM+S and POEM-S are equally safe and effective, with similar procedure duration and a low recurrence rate at short-term follow-up. Future comparative prospective studies with long-term follow-up are required to validate these findings.

Third space endoscopy (TSE) or sub-mucosal endoscopy using a mucosal flap valve (SEMF) enables the endoscopist to operate in the deeper layers of the gastrointestinal tract or gain access to the mediastinal/peritoneal cavity for natural orifice transoral endoscopic surgery (NOTES). TSE procedures are essentially endoscopic surgical procedures with a variable learning curve. Adverse events (AEs) during TSE are specific and follow a certain pattern across the spectrum of TSE procedures. These can be broadly categorized according to either type of AE, time of presentation relative to the procedure or according to degree of severity. Three major categories of AEs encountered during TSE include insufflation related AEs, mucosal injuries (MIs) and bleeding. Other relevant AEs include infectious complications, aspiration pneumonia, post-procedural chest/abdominal pain, atelectasis, cardiac arrhythmias, pleural effusion and pulmonary embolism. Reported incidence of AEs during TSE procedures varies according to the type and complexity of procedure. Acquaintance regarding potential risk factors, technical tips and precautions, alarm signs for early recognition, assessment of degree of severity, morphological characterization of AEs and finally, expeditious selection of appropriate management strategy are crucial and imperative for successful clinical outcomes. The current review discusses the current evidence and practical guidelines for prevention, early detection and management of TSE-related AEs.

Per oral endoscopic myotomy (POEM) has emerged as a preferred approach for the treatment of idiopathic achalasia and various esophageal motility disorders, offering a minimally invasive alternative to traditional laparoscopic Heller's myotomy. Over the past decade, POEM has solidified its status as the primary therapeutic choice in these conditions through constant improvements. Its evolution has been marked by continuous progress, driven by the integration of innovative technologies and sophisticated techniques. Notable advancements in the techniques include the advent of shorter myotomies and sling fiber-preserving gastric myotomies. The introduction of novel image-enhanced endoscopic techniques, such as red dichromatic imaging and much safer bipolar devices, promises to enhance safety and reduce the technical demands of the POEM procedure. Furthermore, significant strides have been made in understanding gastroesophageal reflux (GERD) following POEM, enabling the differentiation of "true reflux" from acidification resulting from fermentation through manual pH tracing assessment. This distinction aids in identifying cases necessitating treatment with proton pump inhibitors. Other treatment strategies of post-POEM GERD have expanded to the incorporation of NOTES fundoplication and device-assisted fundoplication if the necessity arises. This comprehensive review delves into recent developments in POEM, encompassing technical variations, the assessment and management of post-POEM reflux, outcomes in special populations, and future prospects. By exploring these facets, we aim to provide a comprehensive overview of the current state of POEM, shedding light on its evolution and the promising directions it is poised to take in the field of third-space endoscopy.

Achalasia can significantly impair the quality of life. The clinical presentation typically includes dysphagia to both solids and liquids, chest pain, and regurgitation. Diagnosis can be delayed in patients with atypical presentations, and they might receive a wrong diagnosis, such as gastroesophageal reflux disease (GERD), owing to overlapping symptoms of both disorders. Although the cause of achalasia is poorly understood, its impact on the motility of the esophagus and gastroesophageal junction is well established. Several treatment modalities have been utilized, with the most common being surgical Heller myotomy with concomitant fundoplication and pneumatic balloon dilatation. Recently, peroral endoscopic myotomy (POEM) has gained popularity as an effective treatment for achalasia, despite a relatively high incidence of GERD occurring after treatment compared to other modalities. The magnitude of post-POEM GERD depends on its definition and is influenced by patient and procedure-related factors. The long-term sequelae of post-POEM GERD are yet to be determined, but it appears to have a benign course and is usually manageable with clinically available modalities. Identifying risk factors for post-POEM GERD and modifying the POEM procedure in selected patients may improve the overall success of this technique.

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

Reflux after peroral endoscopic myotomy (POEM) is arguably one of the greatest concerns related to the procedure. The exact incidence is difficult to establish as reflux symptoms, esophagitis, and abnormal acid exposure correlate poorly, warranting thorough diagnostic investigation. The incidence is, however, higher than after Heller myotomy or pneumatic dilatation across all these three parameters. Although PPI are effective in the resolution of symptoms and healing of esophagitis, refractory patients exist. Esophageal hypersensitivity and acidic fermentation/esophageal stasis are most likely causes and could be diagnosed by manual analysis of pH metry tracings. Long-term complications like peptic stricture and Barrett's esophagus are rare and reported sporadically. Modifications of POEM procedure aiming to decrease post-POEM reflux led to no conclusive preferred technique. Modern investigations like endoluminal functional lumen imaging probe might help to personalize myotomy to the desired distensibility of the lower esophageal sphincter and decrease reflux.

In this editorial, we respond to a review article by Nabi et al, in which the authors discussed gastroesophageal reflux (GER) following peroral endoscopic myotomy (POEM). POEM is presently the primary therapeutic option for achalasia, which is both safe and effective. A few adverse effects were documented after POEM, including GER. The diagnostic criteria were not clear enough because approximately 60% of patients have a long acid exposure time, while only 10% experience reflux symptoms. Multiple predictors of high disease incidence have been identified, including old age, female sex, obesity, and a baseline lower esophageal sphincter pressure of less than 45 mmHg. Some technical steps during the procedure, such as a lengthy or full-thickness myotomy, may further enhance the risk. Proton pump inhibitors are currently the first line of treatment. Emerging voices are increasingly advocating for the routine combining of POEM with an endoscopic fundoplication method, such as peroral endoscopic fundoplication or transoral incisionless fundoplication. However, more research is necessary to determine the safety and effectiveness of these procedures in the long term for patients who have undergone them.

Peroral endoscopic myotomy (POEM) is an effective and safe treatment for achalasia, but often leads to posttreatment gastroesophageal reflux disease. The aim of this study was to examine the incidence and severity of reflux esophagitis after POEM and to identify associated predictive factors.

Patients who underwent POEM between August 2011 and December 2022 were included. Multivariate logistic regression was used to assess predictive factors for reflux esophagitis after POEM.

In total, 252 patients were included; of which, 46% were female and age ranged between 18 and 87 years. Reflux esophagitis within 1 year after POEM was observed in 131 patients (52%), which was severe in 29 patients (LA grade C/D, 12%). Length of full-thickness myotomy (cm; OR 1.11, 95% CI 1.02-1.21), Eckardt scores before POEM (OR 0.84, 95% CI 0.74-0.96), previous pneumatic dilation (OR 0.51, 95% CI 0.29-0.91), and previous laparoscopic Heller myotomy (LHM; OR 0.44, 95% CI 0.23-0.86) were associated with reflux esophagitis after POEM. Alcohol use (none vs > 7 units per week; OR 3.51, 95% CI 1.35-9.11) and overweight (BMI ≥25 kg/m2; OR 2.67, 95% CI 1.17-6.09) were positive predictive factors and previous LHM (OR 0.13, 95% CI 0.02-0.95) was a negative predictive factor for severe reflux esophagitis after POEM (LA grade C/D).

About half of the patients develop reflux esophagitis after POEM and 12% is graded as severe. Recognizing predictive factors of reflux esophagitis after POEM treatment leads to better patient selection before POEM and provides an opportunity to take preventive measures or start preemptive treatment.

Achalasia cardia, the most prevalent primary esophageal motility disorder, is predominantly characterized by symptoms of dysphagia and regurgitation. The principal therapeutic approaches for achalasia encompass pneumatic dilatation (PD), Heller's myotomy, and the more recent per-oral endoscopic myotomy (POEM). POEM has been substantiated as a safe and efficacious modality for the management of achalasia. Although POEM demonstrates superior efficacy compared to PD and an efficacy parallel to Heller's myotomy, the incidence of gastroesophageal reflux disease (GERD) following POEM is notably higher than with the aforementioned techniques. While symptomatic reflux post-POEM is relatively infrequent, the significant occurrence of erosive esophagitis and heightened esophageal acid exposure necessitates vigilant monitoring to preclude long-term GERD-related complications. Contemporary advancements in the field have enhanced our comprehension of the risk factors, diagnostic methodologies, preventative strategies, and therapeutic management of GERD subsequent to POEM. This review focuses on the limitations inherent in the 24-h pH study for evaluating post-POEM reflux, potential modifications in the POEM technique to mitigate GERD risk, and the strategies for managing reflux following POEM.

GERD is common after peroral endoscopic myotomy (POEM). Selective sparing of oblique fibers may reduce the incidence of reflux esophagitis after POEM. In this study, we compared the incidence of GERD between conventional myotomy (CM) versus oblique fiber-sparing (OFS) myotomy in patients with achalasia.

Eligible patients with type I and II achalasia who underwent POEM from January 2020 to October 2020 were randomized into 2 groups (CM and OFS myotomy). Exclusion criteria were type III achalasia, sigmoid esophagus, and history of Heller's myotomy. The primary study outcome was incidence of reflux esophagitis (at least grade B) in the 2 groups. Secondary outcomes were reflux symptoms, esophageal acid exposure, clinical success, and adverse events.

One hundred fifteen patients were randomized into CM (n = 58) and OFS myotomy (n = 57) groups. POEM was technically successful in all patients. Overall, reflux esophagitis was found in 56 patients (48.7%). The incidence of at least grade B esophagitis was similar in both groups (CM vs OFS myotomy: 25.9% vs 31.6%, P = .541). The mean number of reflux episodes (48.2 ± 36.6 vs 48.9 ± 40.3, P = .933), increased esophageal acid exposure >6% (45.5% vs 31.7%, P = .266), and high DeMeester scores (38.6% vs 41.5%, P = .827) were similar in both groups. There was no difference in the rate of symptomatic reflux (GERD questionnaire score >7) or use of proton pump inhibitors at 1 year.

Sparing of sling fibers has no significant impact on the incidence of significant reflux esophagitis after POEM. Novel strategies need to be explored to prevent reflux after POEM. (Clinical trial registration number: NCT04229342.).

Background and study aims Gastroesophageal reflux disease (GERD) following peroral endoscopic myotomy (POEM) occurs in 40% to 60% of patients. There are limited data evaluating antireflux surgery or transoral incisionless fundoplication (TIF) for refractory post-POEM GERD. Patients and methods In a single-center prospective cohort study, consecutive patients with medically refractory post-POEM regurgitation and/or GERD treated with TIF or combined laparoscopic hernia repair and TIF (cTIF) were evaluated. Baseline evaluation: GERD-Health Related Quality of Life (GERD-HQRL) and Reflux Symptom Questionnaire 7-day recall (RESQ-7) questionnaires, EGD, high-resolution manometry (HRM), 48-hour pH test off proton pump inhibitors (PPIs) and impedance planimetry of the esophagogastric junction (EGJ) to calculate the diameter distensibility index (EGJ-DI). A PPI was taken twice daily for 2 weeks after TIF and restarted later if required. Patients returned 9 to 12 months after treatment when all preoperative studies were repeated. Quality of life, pH studies and EGJ metrics before and after antireflux surgery were compared. Results Seventeen patients underwent TIF (n=2, 12%) or cTIF (n=15, 88%) a mean 25±15 months after POEM. At follow-up a mean of 9±1 months after TIF/cTIF, patients required less frequent daily PPIs (n=0.001), were more satisfied (P=0.008), had improved GERD-HQRL (P=0.001), less intensity and frequency of GERD (P=0.001) and fewer reflux episodes (P=0.04) by pH testing. There was no change in EGJ-DI, EGJ diameter, integrated relaxation pressure, % total time pH <4, or DeMeester score. Conclusions TIF and cTIF for difficult-to-control post-POEM GERD appear safe, decrease PPI use and reflux episodes, and improve QOL without significant change in IRP, EGJ compliance, diameter or esophageal acid exposure time.

Per-oral endoscopic myotomy (POEM) is a minimally invasive procedure that is very effective in the treatment of achalasia, a rare esophageal motility disorder. POEM has become the first-line treatment for achalasia, with high success rates reported in the literature. However, a known complication of POEM is gastroesophageal reflux disease (GERD). The exact cause and risk factors of post-POEM GERD are not fully understood; however, a number of factors have played a role in its development. The management of post-POEM GERD is mainly by conservative measures, such as lifestyle changes and medications, like proton pump inhibitors (PPI), which are often the first-line method of treatment. However, surgical procedures, such as fundoplication, may be necessary in some patients. This literature review will discuss the effectiveness of the use of PPIs as a management strategy for post-POEM GERD, the factors that lead to PPI-resistant GERD, and other management strategies utilized in these cases.

Per oral endoscopic myotomy (POEM) has been shown to be an efficacious and safe therapy for the treatment of achalasia. Compared to laparoscopic Heller myotomy however, no antireflux procedure is routinely combined with POEM and therefore the development of symptomatic or silent reflux is of concern. This study was designed to determine if various patient factors and anatomy would predict the development of gastroesophageal reflux disease post-operatively.

This was a retrospective cohort study of all patients who underwent a POEM at a single institution by a single surgeon over an eight-year period (2014-2022). It has been our practice to obtain a postoperative ambulatory pH test on all patients 6 months after POEM off all acid reducing medications. Patients without a postoperative ambulatory esophageal pH monitoring test were excluded. Age, sex, obesity (BMI > 30), achalasia type, presence of a hiatal hernia, history of prior endoscopic achalasia treatments or myotomy were analyzed using univariate analysis as predictive factors for the development of postoperative GERD (DeMeester score > 14.7 on ambulatory pH monitoring).

There were 179 total patients included in the study with 42 patients (23.5%) having undergone postoperative ambulatory pH testing. The majority of patients (137 or 76.5%) were lost to follow up and did not undergo ambulatory pH testing. Twenty-three out of those 42 patients (55%) had evidence of GERD on ambulatory pH testing. Multiple preoperative patient characteristics including demographics, manometric results, EGD findings, and history of prior achalasia interventions did not correlate with the development of post-operative GERD.

Despite the high rate of reflux after POEM, there does not appear to be any reliable preoperative indicators of which patients have a higher risk of developing post-operative GERD after POEM.

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

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

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

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

NCT03450928.

 The long-term outcomes of esophageal peroral endoscopic myotomy (POEM) are still unknown.

 We searched electronic databases (MEDLINE/PubMed, EMBASE, Scopus) for studies assessing outcomes after POEM for esophageal achalasia with a minimum median follow-up duration of 36 months. Pooled rates of clinical success and postoperative reflux were calculated and compared with the same values at 12/24/36 months when available. Subgroup analyses were performed to explore the interstudy heterogeneity.

 From 1528 initial records, 11 studies (2017-2021) were included. A total of 2342 patients (age 48.1 [SD 6.8] years; 50.1 % males) with a median follow-up of 48 months (interquartile range 45-60) were analyzed. The pooled clinical success rate was 87.3 % (95 %CI 83.6 %-91.0 %; I2  = 73.1 %). The symptomatic reflux pooled rate was 22.0 % (95 %CI 14.4 %-29.5 %; I2  = 92.7 %). Three cases of peptic strictures and one Barrett's esophagus were reported. The pooled rate of severe adverse events was 1.5 % (95 %CI 0.5 %-2.5 %; I2  = 52.8 %).

 Long-term clinical efficacy of POEM persisted in 87 % of patients with achalasia. Post-POEM symptomatic reflux remained stable over time. The risk for Barrett's esophagus and peptic strictures appeared minimal.

Submucosal endoscopy or third-space endoscopy utilizes the potential space between the mucosal and muscularis layers of the gastrointestinal tract to execute therapeutic interventions for various diseases. Over the last decade, endoscopic access to the submucosal space has revolutionized the field of therapeutic endoscopy. Submucosal endoscopy was originally used to perform endoscopic myotomy in patients with achalasia cardia, and its use has grown exponentially since. Currently, submucosal endoscopy is widely used to resect subepithelial tumors and to manage refractory gastroparesis and Zenker's diverticulum. While the utility of submucosal endoscopy has stood the test of time in esophageal motility disorders and subepithelial tumors, its durability remains to be established in conditions such as Zenker's diverticulum and refractory gastroparesis. Other emerging indications for submucosal endoscopy include esophageal epiphrenic diverticulum, Hirschsprung's disease, and esophageal strictures not amenable to conventional endoscopic treatment. The potential of submucosal endoscopy to provide easy and safe access to the mediastinum and peritoneal spaces may open doors to novel indications and rejuvenate the interest of endoscopists in natural orifice transluminal endoscopic surgery in the future. This review focuses on the current spectrum, recent updates, and future direction of submucosal endoscopy in the gastrointestinal tract.

BACKGROUND : Gastroesophageal reflux disease (GERD) and reflux esophagitis remain problems after peroral endoscopic myotomy (POEM). This study aimed to elucidate the risk factors and long-term course of reflux esophagitis and symptomatic GERD after POEM. METHODS : This multicenter cohort study involved 14 high volume centers. Overall, 2905 patients with achalasia-related esophageal motility disorders treated with POEM were analyzed for reflux esophagitis, severe reflux esophagitis (Los Angeles classification C or D), and symptomatic GERD. RESULTS : Reflux esophagitis was diagnosed in 1886 patients (64.9 %). Age ≥ 65 years (risk ratio [RR] 0.85), male sex (RR 1.11), posterior myotomy (RR 1.12), esophageal myotomy > 10 cm (RR 1.12), and gastric myotomy > 2 cm (RR 1.17) were independently associated with reflux esophagitis. Severe reflux esophagitis was diagnosed in 219 patients (7.5 %). Age ≥ 65 years (RR 1.72), previous treatments (RR 2.21), Eckardt score ≥ 7 (RR 0.68), sigmoid-type achalasia (RR 1.40), and esophageal myotomy > 10 cm (RR 1.59) were factors associated with severe reflux esophagitis. Proton pump inhibitors (PPIs) were more effective for reflux esophagitis at 5-year follow-up (P = 0.03) than after 1 year (P = 0.08). Symptomatic GERD was present in 458 patients (15.9 %). Symptom duration ≥ 10 years (RR 1.28), achalasia diagnosis (RR 0.68), integrated relaxation pressure ≥ 26 (RR 0.60), and posterior myotomy (RR 0.80) were associated with symptomatic GERD. The incidence of symptomatic GERD was lower at 5-year follow-up compared with that after 1 year (P = 0.04), particularly in PPI users (P < 0.001). CONCLUSIONS : The incidence of severe reflux esophagitis was low after POEM, but excessive myotomy for older patients with previous treatments should be avoided. Early phase symptomatic GERD is non-acid reflux dependent and the natural course is favorable, basically supporting conservative treatment.

Peroral endoscopic myotomy (POEM) is an established frontline treatment modality for achalasia cardia. Since its initial description, several modifications have been proposed to the technique of POEM. Broadly speaking, these modifications follow the basic principles of submucosal endoscopy, but incorporate variations in the POEM technique, including the difference in the orientation of myotomy (anterior or posterior), length of myotomy (short or long), and thickness of myotomy (selective circular or full thickness). Some of these modifications have been shown to reduce procedural duration without compromising the efficacy of the POEM procedure. More recently, several alterations have been reported that intend to reduce gastroesophageal reflux after POEM. These include preservation of sling fibers during posterior POEM and addition of NOTES fundoplication to the POEM procedure. Although some of the modified techniques have been compared with the conventional techniques in quality trials, randomized studies are awaited for others. The incorporation of some of these modifications will likely make POEM a technically easy and safer modality in near future. This review aims to discuss the current evidence with regard to the impact of modified techniques on the outcome of POEM.

There are limited data correlating symptoms with reflux episodes during pH studies after peroral endoscopic myotomy.

Consecutive patients who underwent POEM followed up ≥6 months later by 48-hour ambulatory wireless pH testing off antisecretory therapy were identified. Reflux symptom association was defined as symptom association probability &gt;95%.

The most frequent symptoms of heartburn (47.2%), cough (45.1%), and chest pain (39.6%) were associated with a positive reflux symptom association (symptom association probability &gt;95%) in 20.9%, 17.1%, and 19.4%, respectively.

There is poor correlation between reported symptoms and esophageal acid exposure during pH testing after POEM.

There is limited data on long-term outcomes of per-oral endoscopic myotomy (POEM). In this study, we aim to evaluate the efficacy of POEM in patients who completed a minimum follow-up of 5 years.

Data of patients who underwent POEM and completed ≥ 5-year follow-up were analyzed, retrospectively. Primary outcome of study was clinical success (Eckardt ≤ 3) at ≥ 5 years after POEM. Secondary outcomes included predictors of dysphagia and symptomatic gastroesophageal reflux disease (GERD) on long-term follow-up.

Three hundred nineteen patients (males 182, mean age 40.5 ± 14.2 years) completed a median of 73-(60-89) month follow-up. Esophageal motility disorders included idiopathic achalasia (type I 26.6%, type II 60.8%, type III 5.6%) and Jackhammer esophagus or distal esophageal spasm (2.8%). POEM was technically successful in 307 (96.2%) patients. Long-term success was 92.6% (overall), 92.1% (type I), 94.7% (type II), 87.5% (type III), and 75% (Jackhammer esophagus/distal esophageal spasm). Symptomatic GERD and reflux esophagitis were detected in 28.9% and 35.3% patients, respectively. On multivariate analysis, young age and female gender were independent risk factors for recurrent dysphagia (p = 0.037) and symptomatic GERD after POEM (p = 0.025), respectively. Lower post-POEM lower esophageal sphincter pressure was an independent predictor for reflux esophagitis (p = 0.016).

POEM is an effective and durable treatment for achalasia and non-achalasia spastic motility disorders. Young patients and females may be at higher risk for recurrent dysphagia and symptomatic GERD, respectively.

Peroral endoscopic myotomy (POEM) is standard treatment for achalasia. Gastroesophageal reflux disease (GERD) after POEM has been an important challenge since the early days of POEM implementation. The esophagogastric junction anti-reflux barrier consists of internal lower esophageal sphincter (LES) (i.e., intrinsic muscles of distal esophagus with sling fibers) and external LES (crural diaphragm and phrenoesophageal ligament anchors the distal esophagus to the crural diaphragm). During conventional POEM, the entire internal LES is unintentionally dissected. Preservation of the sling fiber may reduce post-POEM GERD, but its safety and effectiveness have been unclear. In this study, we investigated the safety and effectiveness of sling fiber preservation POEM (SP-POEM) for reducing severe post-procedural erosive esophagitis.

We analyzed data of 236 patients who underwent POEM; of these, 203 patients underwent posterior myotomy without (Group 1) or with attempted (Group 2) sling fiber preservation. Group 1 (N = 79; sling fiber excision, N = 68) and Group 2 (N = 90; sling fiber preservation, N = 81) were compared. Post-procedural erosive esophagitis (Los Angeles classification) were assessed and the area (direction and length) of mucosal break was also investigated. The gastroesophageal flap valve was evaluated by Hill's classification.

Severe erosive esophagitis exceeding grade C (Los Angeles classification) occurred in 44.1% of patients (30/68) in Group 1 and in 18.5% of patients (15/81) in Group 2. In mapping of erosive esophagitis, mucosal breaks appeared widely in all directions in Group 1; they tended to be limited in Group 2 (especially in the 2 o'clock direction). Assessment using the Hill's classification showed that the gastroesophageal flap valve was preserved after SP-POEM.

SP-POEM is safe and effective, with a success rate of 90%. The rate of severe erosive esophagitis can be decreased by preserving sling fibers.

Per-oral endoscopic myotomy (POEM) is emerging as an effective treatment for pediatric achalasia. There are limited data on the long-term efficacy of POEM in children and adolescents with achalasia. In this study, we aim to evaluate the outcomes of POEM at ≥4 years follow-up.

The data of consecutive children who underwent POEM (September 2013-July 2021) and completed at least 4 years follow-up were analyzed retrospectively. The primary outcome was clinical success (Eckardt ≤ 3) at ≥4 years follow-up. The secondary outcomes included the prevalence of gastroesophageal reflux disease (GERD) and predictors of recurrent symptoms (Eckardt ≥2) after POEM.

A total of 69 children underwent POEM for achalasia during the study period. Of these, 41 (59.4%) children completed ≥4 years [mean 68.5 months (range 48-94)] follow-up, and 38 were included in the final analysis. The subtypes of achalasia included type I (28.9%), type II (60.5%), and type III (2.6%). There was a history of prior treatment in 11 children (28.9%). Clinical success was recorded in 36 (94.7%) patients who successfully underwent POEM. Recurrent symptoms (Eckardt ≥ 2) were noticed in 12 (31.6%) children at ≥4 years. On multivariate analysis, there were no identifiable factors which predicted recurrent symptoms after POEM. Symptomatic GERD and erosive esophagitis were detected in 13.8% (4/29) and 57.1% (8/14) of the children, respectively.

POEM is a durable treatment modality for achalasia in the pediatric population irrespective of the sub-type of achalasia and history of prior treatment.

Esophagitis is prevalent in patients with esophageal dysmotility despite acid suppression, likely related to poor esophageal clearance. Esophageal atresia (EA) is a classic model of dysmotility where this observation holds true. In adult non-dysmotility populations, failure of esophagitis to respond to proton pump inhibitors (PPI) has been linked to variants in CYP2C19 that influence the activity of the encoded enzyme. It is unknown if CYP2C19 metabolizer phenotype contributes to PPI-refractory, non-allergic esophagitis in EA.

We performed a cross-sectional study of 314 children with (N = 188) and without (N = 126) EA who were on PPI therapy at the time of endoscopy to evaluate for possible gastroesophageal reflux disease. Patients with eosinophilic esophagitis and/or fundoplication were excluded. Clinical and histology data were collected. Genomic DNA from biopsy samples was genotyped for polymorphisms in CYP2C19.

CYP2C19 metabolizer phenotypes were not associated with presence or severity of esophagitis (P = 0.994). In a multivariate logistic regression adjusted for potential confounders, EA was the strongest and only significant predictor of esophagitis (odds ratio 2.72, P = 0.023). Using negative binomial regression, we found that CYP2C19 phenotype was not a significant predictor of eosinophil count in children with PPI-refractory esophagitis.

Patients with EA are significantly more likely to experience PPI-refractory, non-allergic esophagitis than controls regardless of CYP2C19 metabolizer phenotype, suggesting that factors other than CYP2C19 genetics, including dysmotility, are the primary drivers of esophagitis in EA. CYP2C19 genotype failed to predict PPI-refractory, non-allergic esophagitis in both EA and non-EA children.

Patients with achalasia frequently develop gastroesophageal reflux (GER)-related symptoms and complications after per-oral endoscopic myotomy (POEM). Reflux symptoms are thought to be due to GER and the current treatment of post-POEM GER focuses on acid suppression with proton pump inhibitors (PPI). However, reflux symptoms in achalasia patients post-POEM can be due to true reflux, nonreflux esophageal acidification due to stasis or acid fermentation, or esophageal hypersensitivity to chemical or mechanical stimuli. True acidic reflux is not always the cause of reflux symptoms. Twenty-four-hour pH monitoring with impedance is essential to differentiate causes of esophageal acidification. PPI is useful only in true acidic reflux. Detection of acid fermentation requires manual review of a 24-h pH study, as automated review often overestimates acid exposure time due to its inability to differentiate true reflux from fermentation. Stasis of ingested acidic food warrants evaluation of esophageal emptying by timed barium esophagogram. In cases of inadequate emptying, esophagogastric junction (EGJ) distensibility can be evaluated by a functional lumen imaging probe. Impaired distensibility with inadequate esophageal emptying suggests treatment failure and may require retreatment. In treatment-refractory patients, esophageal hypersensitivity should be considered and treated with neuromodulators. Thus, the diagnostic approach to post-POEM reflux symptoms should evolve to identify various patterns of esophageal acidification, esophageal emptying patterns, EGJ distensibility, and hypersensitivity. Consequently, the treatment of GER post-POEM should not be limited to treating esophageal acidification by reflux, but should encompass other causes of acidification and esophageal hypersensitivity.

Third space endoscopy (TSE) or submucosal endoscopy provides with the opportunity for minimally invasive management of various gastrointestinal disorders. TSE is a relatively new field and the knowledge on its utility continues to advance. The purpose of this review is to provide with updated evidence on the efficacy and utility of TSE in gastrointestinal motility disorders including achalasia and refractory gastroparesis.

Peroral endoscopic myotomy (POEM) is a safe procedure with emerging evidence on its durability as well. Major technical variations do not appear to impact the outcomes of POEM. Recent randomized trials suggest superiority of POEM over pneumatic dilatation and noninferiority over Heller's myotomy in idiopathic achalasia. With regard to gastric POEM (G-POEM), recent evidence confirms its efficacy in refractory gastroparesis. Although effective, the long-term outcomes of G-POEM are not well known. In addition, the criteria for patient selection remain elusive.

TSE has emerged as a new frontier in the endoscopic management of gastrointestinal motility disorders. While short-term outcomes are encouraging, the durability of TSE remains to be seen in achalasia as well as refractory gastroparesis. Insights regarding patient selection and predictors of outcomes may help optimizing the results of gastric POEM in refractory gastroparesis.

Spastic esophageal motility disorders (SEMD) are a rare group of motility disorders including type III achalasia, distal esophageal spasm (DES), and Jackhammer esophagus (JHE). Limited data suggest that per-oral endoscopic myotomy (POEM) may be effective in these disorders. In this study, we aimed to evaluate the long-term outcomes of POEM in SEMD.

The data of patients with SEMD who underwent POEM (January 2013 to December 2019) were analyzed, retrospectively. The following outcomes were recorded: POEM procedure details, technical and clinical success, adverse events, and gastroesophageal reflux disease (GERD). Clinical success was classified as immediate (<1 y), short-term (1 to 3 y), medium term (3 to 5 y), and long-term (>5 y).

A total of 1115 POEM procedures were performed during the study period for achalasia and nonachalasia spastic motility disorders. POEM was performed for SEMD in 74 (6.6%) patients including type III in 53, DES in 11, and JHE in 10 patients. Technical success was achieved in all the patients. The median follow-up for the entire group was 47.5 months (range: 2 to 77 mo). Clinical success at short-term (1 to 3 y) and long-term follow-up (>5 y) was attained in 85.2% and 82.6% patients, respectively. There was no significant difference in the clinical success between type III achalasia and JHE/DES. Mild and moderate adverse events were recorded in 21 (28.4%) cases. GERD was detected in 23 (56.1%) patients with 24-hour pH study. Erosive esophagitis and symptomatic GERD were found in 36 (48.6%) and 16 (21.6%) patients, respectively.

POEM is a safe, effective, and durable treatment modality for spastic motility disorders of the esophagus. However, GERD is found in about half of the patients mandating close monitoring after POEM.

Background and study aims  Since per-oral endoscopic myotomy (POEM) was introduced in 2010, it has become accepted as one of the standard treatments for esophageal achalasia worldwide. This study aimed to present long-term clinical results of POEM over 10 years and evaluate the technique and outcomes at the institution where it was first used in clinical settings. Patients and methods  Questionnaire-based surveys were sent to patients who received POEM in our institution from September 2008 to May 2010. Patient demographics and procedural outcomes and open-ended questions were posed about the postoperative courses, including symptom improvement and recurrence, additional treatments, and post-POEM gastroesophageal reflux disease (GERD) symptoms. Achalasia symptoms and post-POEM GERD symptoms were evaluated with Eckhardt scores and GerdQ systems, respectively. Results  Thirty-six consecutive POEMs were performed in that period and 10-year follow-up data were obtained from 15 patients (41.7 %). Although four cases (26.7 %) required additional pneumatic balloon dilatation (PBD), reduction in post-Eckardt scores were observed in 14 cases (93.3 %). GerdQ score was positive in one patient (6.7 %). Proton pump inhibitors (PPI) were taken by four patients (26.7 %) and their symptoms were well-controlled. Conclusions  Clinical results of POEM over 10 years were favorable regardless of various factors. Symptoms improved even in patients who required additional treatments, suggesting that POEM plays a significant role in treatment of achalasia.

The incidence of gastroesophageal reflux disease (GERD) is high after per-oral endoscopic myotomy (POEM). GERD after POEM may be qualitatively different from GERD in patients without motility disorders. In this study, we aimed to analyze and compare different aspects of GERD between patients with post-POEM GERD and nonachalasia GERD.

The data of patients with GERD after POEM (January 2018 to June 2019) were compared with that of a control group (nonachalasia GERD group), which included patients presenting with typical reflux symptoms without associated major motility disorders. Patients with lower esophageal sphincter pressure lower than 10 mmHg were excluded from the study. GERD was evaluated at 3 months after POEM. Esophageal acid exposure time higher than 4.2% was used to define GERD. The primary outcome of the study was comparison of GERD-related quality of life and reflux symptom severity between the two groups. In addition, the severity of erosive esophagitis and reflux-symptom association were also recorded in the two groups.

A total of 100 patients were included in the study, with 50 patients in each group (post-POEM GERD vs. controls). The baseline parameters were comparable between the two groups. Median interquartile range of GERD-related quality of life score was significantly lower in the post-POEM group (11 [0-23.3] versus 34 [24-44]; p < 0.001). The post-POEM GERD group had significantly lower median heartburn (6.0 [0-16.3] versus 15.5 [7.5-24.8]; p = 0.001) and regurgitation scores (0 [0-6.0] versus 20.0 [12.3-25.0]; p < 0.001). Erosive esophagitis was more frequent in the post-POEM group (28 [56%] versus 10 [20.4%], p = 0.001). Only three (6%) patients in the post-POEM group had a positive reflux-symptom association as compared with 28 (56%) patients in the control group (p < 0.001).

In selected patients with pH positive GERD after POEM, the symptoms are milder and reflux-symptom association is poor in spite of more severe esophagitis as compared with controls.