This retrospective study aimed to compare treatment outcomes and postoperative courses, including the incidence of esophageal cancer (EC), according to disease types, in 450 achalasia patients who underwent peroral endoscopic myotomy (POEM).

Data from consecutive POEM procedures performed from September 2011 to January 2023 at a single institution were reviewed. Achalasia was classified into straight (St), sigmoid (S1), and advanced sigmoid (S2) types using esophagography findings. Regarding efficacy, POEM was considered successful if the Eckardt score was ≤3. A statistical examination of the incidence and trend of EC occurrence across the disease type of achalasia was conducted using propensity score matching.

Of the 450 patients, 349 were diagnosed with St, 80 with S1, and 21 with S2. POEM efficacy was 97.9% at 1 year and 94.2% at 2 years postprocedure, with no statistical difference between disease types. Using propensity score matching, the incidence of EC in each disease type was as follows: St, 1% (1/98); S1, 2.5% (2/77); S2, 10% (2/18). While no statistical significance was observed between St (1.0%: 1/98) and all sigmoid types (4.0%, 4/95; P = 0.3686). However, a trend test revealed a tendency for EC to occur more frequently in the order of S2, S1, and St type with a statistically significant difference (P = 0.0413).

Outcomes of POEM are favorable for all disease types. After POEM, it is important not only to monitor the improvement of achalasia symptoms but also to pay attention to the occurrence of EC, especially in patients with sigmoid-type achalasia.

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.

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.

Peroral endoscopic myotomy (POEM) is a novel technique within the field of third space endoscopy. The overarching principal is creation of a mucosal incision, careful dissection of the submucosal space using an electrosurgical knife to reach the muscularis (ie, tunneling), performing a controlled myotomy, and finally, closure of the mucosal incision. POEM was first developed for the management of achalasia, and now a decade of evidence shows the procedure is safe, effective, and highly reproducible. Since then, the indications for POEM have expanded to a range of benign upper gastrointestinal (GI) pathologies including cricopharyngeal bar (C-POEM), Zenker's diverticulum (Z-POEM), esophageal diverticula (D-POEM), and gastroparesis (G-POEM). POEM offers the benefit of a minimally invasive alternative to surgical intervention with high clinical success and low rate of adverse events. As the field expands, there is need for more high-quality prospective evidence for the use of POEM within the upper GI tract akin to the ground-breaking work that has been achieved in achalasia. Within this review, we discuss the 5 main indications for POEM, the technical aspects of each corresponding procedure, and analyze the current evidence supporting their use in clinical practice.

Gastroesophageal reflux disease (GERD) after peroral endoscopic myotomy (POEM) has been a limiting factor with POEM. Sling-fiber preservation during POEM was reported to reduce postoperative GERD in Japan. This study investigates the efficacy of this technique in a western population. This is a retrospective, single-center study of patients undergoing POEM from October 2017 to January 2023. The initial cohort of patients were treated by conventional POEM, after which a second cohort underwent POEM with sling-fiber preservation. The primary outcome was the incidence of postoperative reflux symptoms. The secondary outcomes were clinical success rate (Eckardt score ≤ 3), procedure time, and adverse events rate. Multivariate regression was then performed to identify factors associated with the incidence of postoperative reflux symptoms. One hundred and forty eight POEM cases (52.5 ± 15.6 y/o, female: 61[43%]) were included. The mean procedure time (108.6 ± 34.5 vs. 109.1 ± 45.7 min, P = 0.93) was similar between the groups. In the sling-fiber preservation group, gastric myotomy length was significantly longer (2.2 ± 0.7 vs. 1.6 ± 0.8 cm, P < 0.05), yet the incidence rate of postoperative reflux symptoms at follow-up was significantly lower (22.4% vs. 42.3%, P < 0.05). The clinical success rate was similar between groups (89.5% vs. 83.1%, P = 0.32), and the rate of adverse events requiring intervention (13.5% vs. 12.2%, P = 0.36) was similar. Regression analysis indicated that, after adjusting for other risk factors of postoperative GERD, sling-fiber preservation during POEM had an odds ratio of 0.24 (95% CI: 0.07-0.85, P < 0.05) for the incidence of reflux symptoms. Sling-fiber preservation during POEM reduces the incidence of postoperative reflux symptoms. As such, sling-fiber preservation may be a useful solution to reduce post-POEM GERD in western populations.

This article offers a detailed overview of recent advancements in third space endoscopy (TSE), highlighting key procedures and their clinical applications and outcomes. Clinical TSE started as a treatment for achalasia and was named peroral endoscopic myotomy (POEM). Outcome data and comparative data of POEM with other treatments were detailed and discussed. This article also explores the indications and outcomes of other TSE procedures, such as G-POEM, Z-POEM, D-POEM, per-rectal endoscopic myotomy, and STER/POET. This article serves as a valuable resource for endoscopists looking to enhance their understanding and stay updated on these advanced TSE procedures.

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.

Peroral endoscopic myotomy (POEM) has become the first line treatment for achalasia, but controversies remain about the prevalence of gastro-esophageal reflux disease (GERD) after the procedure. The aim of this study was to evaluate post-POEM GERD by a retrospective analysis of a single center cohort.

Achalasia patients aged 18 or above, who underwent POEM between 2012 and 2021, were included, provided they had an endoscopic control of reflux at least one year after POEM. GERD symptoms based on GerdQ questionnaire, and proton pomp inhibitors (PPI) consumption were also evaluated.

Among a consecutive cohort of 422 patients treated by POEM, 254 patients were included. Endoscopic results were available after a mean follow-up of 1.9 ± 1.5 years. 71/254 patients (28 %) had erosive esophagitis (86 % Los Angeles Grade A or B). At the last follow-up (mean 4.5 ± 2.2 years), clinical success of POEM (Eckardt score ≤ 3) was achieved in 79.5 % of patients. 44.5 % of patients were on PPI. Mean GerdQ score was 2.2 ± 2.7, with only 13 patients (6.5 %) with a score ≥ 8.

In this cohort of achalasia patients with an endoscopic follow-up at least 1 year after POEM, GERD did not appear a major threat concern: clinical symptoms were mild in most cases, as was the degree of erosive esophagitis. Furthermore, at the time of last follow up, less than half of patients required treatment with PPI.

Per-oral endoscopic myotomy (POEM) is an innovative minimally invasive technique and has emerged as the preferred modality for treating achalasia and spastic esophageal disorders in numerous specialized centers worldwide. Gastroesophageal reflux (GER) is a common complication following POEM procedures. Recently, an article in the World Journal of Gastroenterology, providing a comprehensive update on post-POEM GER. In this article, the authors present novel insights and strategies that offer valuable implications for endoscopy.

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.

High-resolution manometry (HRM) and esophagography are used for achalasia diagnosis; however, achalasia phenotypes combining esophageal motility and morphology are unknown. Moreover, predicting treatment outcomes of peroral endoscopic myotomy (POEM) in treatment-naïve patients remains an unmet need.

In this multicenter cohort study, we included 1824 treatment-naïve patients diagnosed with achalasia. In total, 1778 patients underwent POEM. Clustering by machine learning was conducted to identify achalasia phenotypes using patients' demographic data, including age, sex, disease duration, body mass index, and HRM/esophagography findings. Machine learning models were developed to predict persistent symptoms (Eckardt score ≥3) and reflux esophagitis (RE) (Los Angeles grades A-D) after POEM.

Machine learning identified three achalasia phenotypes: phenotype 1, type I achalasia with a dilated esophagus (n = 676; 37.0%); phenotype 2, type II achalasia with a dilated esophagus (n = 203; 11.1%); and phenotype 3, late-onset type I-III achalasia with a nondilated esophagus (n = 619, 33.9%). Types I and II achalasia in phenotypes 1 and 2 exhibited different clinical characteristics from those in phenotype 3, implying different pathophysiologies within the same HRM diagnosis. A predictive model for persistent symptoms exhibited an area under the curve of 0.70. Pre-POEM Eckardt score ≥6 was the greatest contributing factor for persistent symptoms. The area under the curve for post-POEM RE was 0.61.

Achalasia phenotypes combining esophageal motility and morphology indicated multiple disease pathophysiologies. Machine learning helped develop an optimal risk stratification model for persistent symptoms with novel insights into treatment resistance factors.

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.

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.

 Peroral endoscopic myotomy (POEM) is a minimally invasive endoscopic procedure for achalasia; its indication has expanded from adults to children. We aimed to evaluate the postoperative efficacy and antireflex status of POEM in young children with achalasia aged 12 years or younger.

AND METHODS:  Pediatric patients with achalasia aged 18 years or younger who underwent POEM in our hospital between 2016 and 2021 were included and divided into two age groups: group A (≤ 12 years) and group B (13-18 years). The success rate (Eckardt score ≤ 3), endoscopic reflux findings, and antiacid use at 1 year postoperatively were compared between the groups.

 Ten patients (four boys and six girls; Chicago classification type I: five, type II: four, and unclassified: one) were included. Mean age and preoperative Eckardt scores in groups A (n = 4) and B (n = 6) were 9.2 ± 3.0 versus 15.6 ± 0.6 years (p = 0.001) and 5.5 ± 3.9 versus 7.2 ± 3.7 (p = 0.509), respectively, and mean operative time and myotomy length were 51.3 ± 16.6 versus 52.5 ± 13.2 minutes (p = 0.898) and 10.8 ± 4.6 versus 9.8 ± 3.2 cm (p = 0.720), respectively. The 1-year success rate was 100% in both groups. Mild esophagitis (Los Angeles classification B) was endoscopically found in one patient in each group (16.7 vs. 25.0%, p = 0.714), and antiacid use was required in three patients (group A, two; group B, one; 50.0 vs. 16.7%, p = 0.500).

 The success rate of POEM within 1 year in young children with achalasia aged 12 years or younger was equal to that in adolescent patients. However, young children tended to require antiacids 1 year postoperatively; therefore, long-term follow-up is necessary.

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.

Our review delves into the realm of peroral endoscopic myotomies (POEMs) in the upper gastrointestinal tract (UGT). In recent years, POEMs have brought about a revolution in the treatment of UGT motility disorders. Esophageal POEM, the first to be introduced, has now been validated as the primary treatment for achalasia. Subsequently developed, G-POEM displays promising results in addressing refractory gastroparesis. Over time, multiple endoscopic myotomy techniques have emerged for the treatment of Zenker's diverticulum, including Z-POEM, POES, and hybrid approaches. Despite the well-established efficacy outcomes, new challenges arise in the realm of POEMs in the UGT. For esophageal POEM, the future scenario lies in customizing the myotomy extent to the minimum necessary, while for G-POEM, it involves identifying patients who can optimally benefit from the treatment. For ZD, it is crucial to validate an algorithm that considers various myotomy options according to the diverticulum's size and in relation to individual patients. These challenges align with the concept of precision endoscopy, personalizing the technique for each subject. Within our text, we comprehensively examine each myotomy technique, analyzing indications, outcomes, and adverse events. Additionally, we explore the emerging challenges posed by myotomies within the context of the evolving field of precision endoscopy.

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.

Third-space endoscopy, also known as submucosal endoscopy, allows for a wide range of therapeutic interventions within the submucosal layer and even into the muscular or subserosal layers of the gastrointestinal lumen. The technical development of peroral endoscopic myotomy (POEM) for achalasia has revolutionized the field of therapeutic endoscopy and the method has been continuously refined and modified. Although POEM has been applied to treat primary achalasia, it shows a favorable clinical response in other esophageal motility disorders and as a salvage treatment after previously failed intervention. Gastroesophageal reflux after POEM has drawn considerable attention and there have been major advancements in its prevention and management. POEM has led to advantageous derivatives such as peroral endoscopic tumor resection or submucosal tunneling endoscopic resection for resection of subepithelial lesions, Zenker POEM for hypopharyngeal diverticula, diverticular POEM for epiphrenic esophageal diverticula, and gastric POEM for refractory gastroparesis. These techniques have a similar concept, which constitutes submucosal tunneling with a mucosal flap valve and secure mucosal incision closure. The submucosal tunneling technique is widely accepted and continues to evolve. This study aimed to review in detail the indications, outcomes, and technical variations in POEM and explore several emerging submucosal tunneling procedures. This review will benefit future studies by providing a summary of recent developments in this field.