AGA Clinical Practice Update on Gastric Peroral Endoscopic Myotomy for Gastroparesis: Commentary.

DESCRIPTION: The purpose of this American Gastroenterological Association (AGA) Institute Clinical Practice Update (CPU) is to review the available evidence and provide expert advice regarding cognitive, procedural, and post-procedural aspects of performing gastric peroral endoscopic myotomy for the treatment of refractory gastroparesis. METHODS: This CPU was commissioned and approved by the AGA Institute Clinical Practice Updates Committee (CPUC) and the AGA Governing Board to provide timely guidance on a topic of high clinical importance to the AGA membership and underwent internal peer review by the CPUC and external peer review through standard procedures of Gastroenterology. This expert commentary incorporates important as well as recently published studies in this field, and it reflects the experiences of the authors who are advanced endoscopists with expertise in treating patients by performing third-space endoscopy and gastric peroral endoscopic myotomy.

Gastric per-oral endoscopic myotomy versus pyloric injection of botulinum toxin for the treatment of gastroparesis: our institutional experience and a systematic review of the literature.

INTRODUCTION: Gastric Per-Oral Endoscopic Myotomy (GPOEM) has been developed as an effective treatment option for patients with medically refractory gastroparesis. Other endoscopic options, such as pyloric injection of botulinum toxin (Botox), is often performed with limited efficacy. The purpose of this study was to evaluate GPOEM for the treatment of gastroparesis and compare its efficacy to Botox injection results reported in the literature. METHODS: A retrospective review was conducted to identify all patients who underwent a GPOEM for the treatment of gastroparesis between September 2018 and June 2022. Changes in Gastric Emptying Scintigraphy (GES) studies and Gastroparesis Cardinal Symptom (GCSI) scores from the preoperative to postoperative period were analyzed. In addition, a systematic review was conducted to identify all publications reporting the outcomes of Botox injections for the treatment of gastroparesis. RESULTS: A total of 65 patients (51 female, 14 male) underwent a GPOEM during the study period. Twenty-eight patients (22 female, 6 male) had both preoperative and postoperative GES studies in addition to GCSI scores. The etiologies of gastroparesis were diabetic (n = 4), idiopathic (n = 18), and postsurgical (n = 6). Fifty percent of these patients had undergone previous failed interventions including Botox injections (n = 6), gastric stimulator placement (n = 2), and endoscopic pyloric dilation (n = 6). Outcomes showed a significant decrease in GES percentages (mean difference = - 23.5%, p < 0.001) and GCSI scores (mean difference = - 9.6, p = 0.02) postoperatively. In the systematic review for Botox, transient mean improvements in postoperative GES percentages and GCSI scores were reported at 10.1% and 4.0, respectively. CONCLUSION: GPOEM leads to significant improvement in GES percentages and GCSI scores postoperatively and is superior to Botox injection results reported in the literature.

POEM, GPOEM, and ZPOEM.

Our tripartite narrative review discusses Peroral Endoscopic Myotomy (POEM), gastric POEM (GPOEM) and POEM for Zenker's diverticula (ZPOEM). POEM is the prototypical procedure that launched the novel "3rd space endoscopy" field of advanced endoscopy. It revolutionized achalasia therapy by offering a much less invasive version of the prior gold standard, the laparoscopic Heller myotomy (HM). We review in detail indications, outcomes, technique variations and comparative data between POEM and HM particularly with regard to the hotly debated issue of GERD. We then proceed to discuss two less illustrious but nevertheless important offshoots of the iconic POEM procedure: GPOEM for gastroparesis and ZPOEM for the treatment of hypopharyngeal diverticula. For GPOEM, we discuss the rationale of pylorus-directed therapies, briefly touch on GPOEM technique variations and then focus on the importance of proper patient selection and emerging data in this area. On the third and final part of our review, we discuss ZPOEM and expound on technique variations including our "ultra-short tunnel technique". Our review emphasizes that, despite the superiority of endoscopy over surgery for the treatment of hypopharyngeal diverticula, there is no clear evidence yet of the superiority of the newfangled ZPOEM technique compared to the conventional endoscopic myotomy technique practiced for over two decades prior to the advent of ZPOEM.

Real-time intraoperative functioning lumen imaging probe during endoscopic per-oral pyloromyotomy (pop).

BACKGROUND: Endoscopic per-oral pyloromyotomy (POP) has emerged as a safe and effective first line option in medically refractory gastroparesis. Determining the appropriate extent of the pyloromyotomy continues to present a challenge as there are no standardized tools for measuring changes in pyloric distensibility during the procedure. The objective of this study was to evaluate the utility of using impedance planimetry with endoscopic functional luminal imaging probe (FLIP) to measure changes in pyloric distensibility after POP, and to compare these changes with improvement in symptoms and objective gastric emptying. METHODS: Patients with medically refractory gastroparesis underwent POP with FLIP measurements of the pylorus (EndoFLIP®, Medtronic, Fridley MN). FLIP measurements, as well as changes in symptoms measured by the validated gastroparesis cardinal symptom index (GCSI) and scintigraphic gastric emptying studies (GES), were evaluated before and after POP. RESULTS: A total of 14 patients underwent measurement with FLIP during POP, 12 of whom had pre- and post-POP measurements. Mean pyloric diameter increased by 1.4 mm, from 13.9 mm to 15.3 mm (p = 0.0012). Mean distensibility index increased from 6.2 mm2/mmHg to 9.1 mm2/mmHg (p = 0.0074). Successful division of the pylorus was achieved in 100% of patients with a mean operative time of 36 min and no perioperative complications. The mean length of stay was 0.7 days (0-3 days). Post-POP mean GCSI score improved from 2.97 to 2.28 at a mean follow-up time of 27 days (p < 0.001). Objective improvement in gastric emptying was observed in 80% of patients with scintigraphic GES, with mean four-hour retention decreasing from 46.3% to 32.4% (p < 0.007). CONCLUSIONS: FLIP is a safe and feasible tool to provide objective measurements during POP. Larger cohorts with longer follow-up are required to determine if measured improvements in pyloric diameter and distensibility are predictive of sustained improvements in GCSI and GES.

DUAL-POEM for associated esophageal and gastric motility disorders: case series of endoscopic cardiomyotomy and endoscopic pyloromyotomy.

Background: Per-oral esophageal myotomy endoscopic (E-POEM) has clearly proved safety and efficiency in the treatment of esophageal spastic disorders. Recent studies on endoscopic pyloromyotomy (G-POEM) suggest good efficiency and safety in the treatment of gastroparesis. In recent literature, some reports showed both esophageal motility disorders and gastroparesis.Methods: We report the case of four patients with esophageal and gastric motility disorders who were successfully treated with DUAL POEM (E-POEM and G-POEM) in two separate procedures.Results: Clinical improvement was reported in all patients with a decrease of the Eckardt score for esophageal motility disorders and a decrease of the GCSI score for gastroparesis. No adverse events occurred after any procedure. These reported cases suggest that is possible to perform an E-POEM and a G-POEM in the same patient in two distinct procedures.Conclusions: DUAL POEM seems to be faisable in patient with esophageal motility disorders associated with gastroparesis. The possibility of the concomitant occurrence of esophageal and gastric motility disorders could lead to change in practices with an overall assessment including gastric empting scintigraphy, high resolution manometry and pH-impedancemetry for patients with digestive motility disorders.

Clinical efficacy of gastric per-oral endoscopic myotomy (G-POEM) in the treatment of refractory gastroparesis and predictors of outcomes: a systematic review and meta-analysis using surgical pyloroplasty as a comparator group.

BACKGROUND AND AIMS: Gastric peroral endoscopic myotomy (G-POEM) is a novel minimally invasive technique in endosurgery. Data is limited as to its efficacy, safety, and predictive factors. We conducted this meta-analysis to evaluate the clinical outcomes of G-POEM and used the outcomes of surgical pyloroplasty as a comparator group in the treatment of refractory gastroparesis. METHODS: We searched multiple databases from inception through March 2019 to identify studies that reported on G-POEM and pyloroplasty in gastroparesis. Our primary outcome was to analyze and compare the pooled rates of clinical success, in terms of Gastroparesis Cardinal Symptom Index (GCSI) score and 4-h gastric emptying study (GES) results, with G-POEM and pyloroplasty. RESULTS: Three hundred and thirty-two and 375 patients underwent G-POEM (11 studies) and surgical pyloroplasty (seven studies), respectively. The pooled rate of clinical success, based on the GCSI score, with G-POEM was 75.8% (95% CI 68.1-82.1, I2 = 50) and with surgical pyloroplasty was 77.3% (95% CI 66.4-85.4, I2 = 0), with no significance, p = 0.81. The pooled rate of clinical success, based on the 4-hour GES results, with G-POEM was 85.1% (95% CI 68.9-93.7, I2 = 74) and with surgical pyloroplasty was 84% (95% CI 64.4-93.8, I2 = 81), with no significance, p = 0.91. The overall adverse events were comparable. Based on meta-regression analysis, idiopathic gastroparesis, prior treatment with botulinum toxin and gastric stimulator seemed to predict clinical success with G-POEM. CONCLUSION: G-POEM demonstrates clinical success in treating refractory gastroparesis. Idiopathic gastroparesis, prior treatment with botulinum injections and gastric stimulator appear to have positive predictive effects on the 4-h GES results after G-POEM. Outcomes seem comparable to surgical pyloroplasty.

Per oral pyloromyotomy utilizing a lesser curvature approach: how we do it.

BACKGROUND: The treatment of gastroparesis refractory to medical therapy has evolved to include purely endoscopic techniques. Per oral pyloromyotomy (POP) has evolved from traditional laparoscopic or open pyloroplasty to become a safe and effective minimally invasive option for patients with gastroparesis. As compared to laparoscopic pyloroplasty (LP), POP produces similar improvements in gastric emptying and symptom mitigation, while having shorter lengths of stay. There are slight variations in technique that vary by institution. Described here is a technique utilizing a lesser curve approach, with a mucosotomy closure using clips in an effort to maximize efficiency of the procedure. METHODS: Preoperative workup includes a scintigraphic gastric emptying study or a wireless motility capsule study, and the Gastroparesis Cardinal Symptom Index (GCSI). After an upper endoscopy, the procedure begins with injection into the submucosal space with methylene blue in saline on the lesser curve, 3-5 cm proximal to the pylorus. A 1.5 cm incision is then made with the ERBE hybrid knife. A submucosal tunnel is created past the distal end of the pylorus, and the muscle is hooked, and divided with the hybrid knife. The mucosotomy is closed with clips (Boston Scientific Resolution 360, Boston, MA) after the completion of the myotomy. Post-operatively, patients are discharged home after an overnight stay with a proton pump inhibitor, sucralfate, and a full liquid diet for 2 weeks. CONCLUSIONS: A lesser curve approach with mucosotomy closure using clips is a safe, effective, and efficient modality for performing POP. As more centers adopt POP as a tool for gastroparesis management, the lesser curve method limits the length of the submucosal tunnel needed, and allows for wide adoption of the technique.

Targeting the pylorus in gastroparesis: From physiology to endoscopic pyloromyotomy.

BACKGROUND: The pylorus plays a key role in the control of gastric content outflow. Impairment of pyloric physiology has been observed in gastroparesis, particularly when associated with diabetes mellitus or opioid intake or after antireflux surgery. New tools have been developed to identify pyloric dysfunction in routine care, including functional luminal impedance planimetry (FLIP). As such, a new therapeutic strategy targeting the pylorus, namely endoscopic pyloromyotomy (G-POEM), has received increasing attention and emerged as a promising treatment for gastroparesis. PURPOSE: The present review details the involvement of the pyloric pathophysiology in gastroparesis, as well as clinical results of G-POEM according to the current literature.

Indications and Outcomes of Per Oral Endoscopic Myotomy from Mouth to Anus.

Third space endoscopy or submucosal endoscopy using a mucosal flap valve allows secure access to the submucosal and deeper layers of the gastrointestinal tract without the risk of a full-thickness perforation. This allows the performance of submucosal tunneling and myotomy for spastic segments of the gastrointestinal tract. Per oral endoscopic myotomy (POEM) has been described for the treatment of achalasia cardia and other spastic esophageal disorders and is widely implemented. Endoscopic pyloromyotomy (G-POEM) has been performed for the treatment of refractory gastroparesis. Z-POEM for Zenker's diverticulum, D-POEM for epiphrenic diverticulum, and per-rectal endoscopic myotomy for treatment of Hirschsprung's disease are described..

Gastric per-Oral Endoscopic Myotomy for Refractory Gastroparesis: A Meta-Analysis.

BACKGROUND: The emerging gastric per-oral endoscopic myotomy (G-POEM) is becoming an alternative treatment method for gastroparesis. This study aimed to evaluate the feasibility and safety of G-POEM for gastroparesis. METHODS: Relevant publications were identified through searching PubMed, EMBASE, Cochrane Library, and Web of Science before April 1, 2019. Studies presenting the clinical data of G-POEM for the treatment of gastroparesis were included. Data about effectiveness and safety were extracted, pooled, and analyzed. Forest plots were graphed based on random effects models. RESULTS: A total of 272 patients representing 8 studies were eligible for analysis. The pooled rates of GCSI at preprocedure, 1-3 months, 6 months, and 12 months, were 3.25 (95% CI, 2.75-3.75), 1.80 (95% CI, 1.10-2.49), 1.56 (95% CI, 0.45-2.68), and 1.10 (95% CI, 0.75-1.45), respectively. The pooled results of 4-h GES pre- and post-G-POEM were 41.89% (95% CI, 32.75-51.03%) and 16.48% (95% CI, 9.83-23.14%), respectively. Furthermore, the pooled clinical response rate was 84% (95% CI, 77-89%). The GES improvement rate and GES normal rate were also analyzed, and the results were 84% (95% CI, 77-90%) and 53% (95% CI, 39-66%), respectively. Finally, the pooled adverse events rate was 12% (95% CI, 6-19%). CONCLUSIONS: G-POEM was shown to be feasible and safe for the treatment of gastroparesis with various etiologies, which could be a potential first-line therapy for certain patients. Future studies are needed to investigate the appropriate patients for G-POEM to explore the "most beneficial" subgroup of patients.

Peroral Pyloromytomy is Effective and Safe for Postsurgical Gastroparesis.

Gastric Per-oral Endoscopic pyloromyotomy (G-POEM) or per-oral pyloromyotomy (POP) is a novel procedure recently described for treatment of medically refractory gastroparesis; however, its efficacy and safety is not clear in patients with postsurgical gastroparesis (PsGP). We conducted a systematic review and meta-analysis to determine the efficacy and safety of G-POEM in PsGP. A total of 6 studies were included in the analysis. The pooled rate of success by gastroparesis cardinal symptom index (GCSI) and 4-h gastric emptying study (GES) were 89.6% (95% C.I. 72.7-96.5) and 81.5% (95% CI 47.8-95.5) respectively. There was a statistically significant improvement in GCSI score after 3 months of G-POEM as compared with pre G-POEM GCSI scores (2.7 (95% C.I. 0-5.5) vs 8.2 (95% C.I. 5.4-11) (p = 0.007). The mean pre G-POEM 4 h GES was 93.8% (95% C.I. 42.3-145.3) with improvement in post G-POEM GES to 44.5% (95% C.I. 0-95)(p = 0.2). The pooled rate of total adverse events was 9% (95% C.I. 2.7-25.9). Our study showed a good clinical success of G-POEM in PsGP patients along with significant improvement in 3-month GCSI scores. There was an improvement of GES after G-POEM, but it did not reach statistical significance. In conclusion, G-POEM is an effective and safe treatment option for PsGP.

Technical Aspects of Peroral Endoscopic Pyloromyotomy.

Gastric peroral endoscopic pyloromyotomy (G-POEM or POP) is a feasible and effective procedure for the treatment of refractory gastroparesis. G-POEM is a technically demanding endoscopic procedure. As of yet, there is no consensus on the technique. A variety of techniques have been reported in published studies. The essential technical steps of the procedure are (1) establishment of submucosal tunnel in gastric antrum, (2) identification of the pyloric muscular ring, (3) selective circular myotomy, and (4) a 2.5-cm to 3.0-cm length of myotomy. There are still some technical questions unanswered, and more studies are needed to establish standardized techniques and possible improvement of outcomes.

How I Do It: Per-Oral Pyloromyotomy (POP).

INTRODUCTION: Several surgical treatments exist for treatment of gastroparesis, including gastric electrical stimulation, pyloroplasty, and gastrectomy. Division of the pylorus by means of endoscopy, Per-Oral Pyloromyotomy (POP), is a newer, endoluminal therapy that may offer a less invasive, interventional treatment option. METHODS: We describe and present a video of our step by step technique for POP using a lesser curvature approach. The following are technical steps to complete the POP procedure from the lesser curve approach. CONCLUSION: In our experience, these methods provide promising initial results with low operative risks, although long-term outcomes remain to be determined.

Gastric peroral endoscopic pyloromyotomy (G-POEM) as a salvage therapy for refractory gastroparesis: a case series of different subtypes.

BACKGROUND: Gastroparesis is a poorly understood, chronic, debilitating motility disorder with very limited medical therapeutic options. Gastric peroral endoscopic pyloromyotomy (G-POEM) is an emerging novel endoscopic technique as an incisionless pyloroplasty for refractory cases. Effective information of G-POEM on different types of gastroparesis is sparse. METHODS: Cases of G-POEM using selective circular myotomy as a salvage therapy for refractory symptoms were retrospective studied. The G-POEM procedures were performed by a single expert endoscopist under a certain protocol. Gastroparesis Cardinal Symptoms Index (GCSI) and gastric emptying scintigraphy (GES) were evaluated before and after the procedure. Procedures related adverse event were also recorded. KEY RESULTS: All procedures were successfully completed without complications. Each case in this series was different in demography and etiology of gastroparesis, namely postsurgical, postinfectious, and idiopathic gastroparesis in an elderly male and two young female adults. All cases were refractory to conventional treatment but demonstrated obvious success after G-POEM as a salvage therapy both clinically and on GES. CONCLUSIONS & INFERENCES: G-POEM as a salvage therapy improves symptoms and gastric emptying in patients with different types of refractory gastroparesis. Our cases are also the firsts to show success of G-POEM in postinfectious gastroparesis and in elderly male patient. More data are needed to determine which subgroup of patients would benefit most from this novel procedure.