One-year results of gastric peroral endoscopic myotomy for refractory gastroparesis: a French multicenter study

Gastric peroral endoscopic myotomy versus botulinum toxin injection for the treatment of refractory gastroparesis: results of a double-blind randomized controlled study

INTRODUCTION

Gastric peroral endoscopic myotomy (G-POEM) is a promising technique for treating refractory gastroparesis. We present the first double-blind randomized study comparing the clinical efficacy of G-POEM versus pyloric botulinum toxin injection (BTI).

METHODS

This randomized study, conducted in two expert centers, enrolled patients with refractory gastroparesis, medically managed for >6 months and confirmed by gastric emptying scintigraphy (GES), into two groups, G-POEM versus BTI, with follow-up of 1 year. The primary end point was the 3-month clinical efficacy, defined as a >1-point decrease in the mean Gastroparesis Cardinal Symptom Index (GCSI) score. Secondary end points were: 1-year efficacy, GES evolution, adverse events, and quality of life.

RESULTS

40 patients (22 women; mean age 48.1 [SD 17.4]), with mean symptom duration of 5.8 (SD 5.7) years, were randomized. Etiologies included idiopathic (n=18), diabetes (n=11), postoperative (n=6), and mixed (n=4). G-POEM showed a higher 3-month clinical success than BTI (65% vs. 40%, respectively; P=0.10), along with non-significantly higher 1-year clinical success (60% vs. 40%, respectively) on intention-to-treat analysis. The GCSI decreased in both groups at 3 months and 1 year. Only three minor adverse events occurred in the G-POEM group. The GES improvement rate was 72% in the G-POEM group versus 50% in the BTI group (non-significant).

CONCLUSION

G-POEM seems to have a higher clinically relevant success rate than BTI, but this was not statistically demonstrated. This study confirms the interest in treatments targeting the pylorus, either mechanically or chemically, for managing refractory gastroparesis.

Efficacy and Safety of Gastric Per-Oral Endoscopic Myotomy (G-POEM): A Systematic Review and Meta-Analysis

BACKGROUND

Gastric per-oral endoscopic myotomy (G-POEM) is an innovative treatment that has become increasingly utilized for patients with refractory gastroparesis. The aim of this systematic review and meta-analysis was to evaluate the safety and effectiveness of G-POEM for the treatment of gastroparesis.

METHODS

Individualized search strategies were developed through February 2021 in accordance with the PRISMA and MOOSE guidelines. This meta-analysis was performed by calculating pooled proportions and mean difference preprocedure and postprocedure with rates estimated using random effects models. Measured outcomes included technical success, clinical success, improvement in gastroparesis cardinal symptom index (GCSI), change in gastric emptying rate, alterations in impedance planimetry (functional lumen imaging probe [FLIP]) assessment, and adverse events.

RESULTS

A total of 20 studies (n=797 patients; 67.41% female) were included. The mean age was 48.92±11.61 y, with an average duration of 4.24±1.11 y since gastroparesis diagnosis. Technical success was 98.47% [(95% CI: 97.14, 99.19);I2=0.00] with a mean myotomy length of 3.78±1.16 cm. In terms of clinical success, mean preprocedure GCSI scores were 3.38±0.37 and improved significantly postprocedure [weighted mean difference -1.56 (95% CI: -1.89 to -1.24); I2=82.53; P<0.001]. Gastric retention after 4 hours demonstrated ~50% improvement (preprocedure 43.08±9.24% versus postprocedure 22.97±10.19%; P<0.001). FLIP assessment with 40 mL and 50 mL balloons demonstrated a significant increase in diameter, distensibility index, and cross-sectional area postprocedure (all P<0.05). Procedure-associated adverse events occurred among 10.92% [(95% CI 5.09 to 19.32); I2=82.85] of patients.

CONCLUSION

G-POEM appears safe and highly effective for the treatment of patients with refractory gastroparesis regardless of symptom predominance or etiology.

Applications of gastric peroral endoscopic myotomy in the treatment of upper gastrointestinal tract disease

Gastric peroral endoscopic myotomy (G-POME) is an emerging minimally invasive endoscopic technique involving the establishment of a submucosal tunnel around the pyloric sphincter. In 2013, Khashab et al used G-POME for the first time in the treatment of gastroparesis with enhanced therapeutic efficacy, providing a new direction for the treatment of gastroparesis. With the recent and rapid development of G-POME therapy technology, progress has been made in the treatment of gastroparesis and other upper digestive tract diseases, such as congenital hypertrophic pyloric stenosis and gastric sleeve stricture, with G-POME. This article reviews the research progress and future prospects of G-POME for the treatment of upper digestive tract gastrointestinal diseases.

Precision Endoscopy in Peroral Myotomies for Motility Disorders of the Upper Gastrointestinal Tract: Current Insights and Prospective Avenues-A Comprehensive Review

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.

A Systematic Review of the Long-Term Clinical Success of Gastric Peroral Endoscopic Myotomy for Refractory Gastroparesis

Gastroparesis is a chronic and debilitating gastrointestinal disorder with few medical treatment options. Traditional surgical management has involved laparoscopic pyloromyotomy or gastric stimulation. In recent years, gastric peroral endoscopic myotomy (GPOEM) has become an attractive, less invasive option for patients with refractory gastroparesis. There is little information on the long-term clinical success of GPOEM in patients with refractory gastroparesis. This systematic review aims to evaluate the data on this procedure's long-term clinical efficacy and safety. A comprehensive literature review was done in PubMed, EMBASE, Ovid, and Google Scholar databases from the date of earliest entry in May 2017 up to August 15, 2022. The Gastroparesis Cardinal Symptom Index (GCSI) score, adverse reaction, and length of stay were analyzed. Eleven studies were eligible for inclusion (900 patients), seven of the studies were retrospective, while four were prospective. The GCSI is a 6-point Likert scale questionnaire that assesses improvement in gastroparesis. An average decrease of GCSI by 1 point compared to baseline GCSI for all patients (described as clinical success) was found in 662 patients out of 713 (92.8%) at one-year follow-up, 421 out of 460 (91.5%) at two-year follow-up, 270 out of 270 (100%) at three-year follow-up, and 102 out of 102 (100%) at four-year follow-up. Adverse events occurred in 62 out of 835 patients (in nine studies), with two of the most frequent being bleeding and mucosal tears. GPOEM is an effective and safe treatment option for patients with refractory gastroparesis, with symptom improvement noted up to four years postoperatively.

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.

POEM from A to Z: current perspectives

The "third space endoscopy" or also called "submucosal endoscopy" is a reality we can transfer to our patients since 2010. Various modifications of the submucosal tunneling technique allow access to the submucosa or deeper layers of the gastrointestinal tract. In addition to peroral endoscopic myotomy for the treatment of achalasia, also called esophageal POEM, other variants have emerged that make it possible to treat different esophageal motility disorders, esophageal diverticula, subepithelial tumors of various locations, gastroparesis, reconnection of complete esophageal strictures or even thanks to exceptional endoscopists, pediatric disorders such as Hirschsprung's disease. Although some technical aspects are yet to be standardized, these procedures are becoming widespread worldwide and will likely become the standard treatment of these pathologies soon.

Predictors of favorable outcome after pyloroplasty for gastroparesis: should response to pyloric dilation or Botox injection be used as a marker of surgical outcome?

INTRODUCTION

Pyloroplasty and gastric peroral endoscopic myotomy (G-POEM) are effective surgeries for gastroparesis. The primary aim of this study was to evaluate outcomes of pyloroplasty and G-POEM in patients with gastroparesis and determine factors associated with favorable outcome. The secondary aim was to assess the utility of clinical response to preoperative pyloric dilation or botulinum toxin injection (Botox) on surgical outcome, a factor conventionally used as a favorable marker.

METHODS

There were 204 patients who underwent pyloroplasty (n = 177) or G-POEM (n = 27) for gastroparesis at our institution from 2014 to 2021. Demographic and clinical parameters were analyzed to assess their impact on surgical outcome. A subgroup of patients who had pyloric dilation or Botox injection were assessed separately. Favorable outcome was defined as patient reported complete resolution of the predominant gastroparesis symptom.

RESULTS

Favorable outcome was achieved in 78.4% of patients (pyloroplasty: 79.7% and G-POEM: 70.4%, p = 0.274). Among 61 patients where pre- and postoperative gastric emptying studies (GES) were available, mean 4-hour retention significantly improved from 33.5 to 15.0% (p < 0.001) and 77.0% of patients achieved normalization. Favorable outcome was not significantly impacted by etiology of gastroparesis (p = 0.120), GERD (p = 0.518), or primary gastroparesis symptom (p = 0.244). Age ≥ 40 was a significant predictor of favorable surgical outcome on multivariate analysis [OR: 2.476 (1.224-5.008), p = 0.012]. Among the patients who had preoperative dilation (n = 82) or Botox injection (n = 46), response to these interventions was not a predictor of favorable surgical outcome (p = 0.192 and 0.979, respectively). However, preoperative Botox injection, regardless of response to injection, was associated with favorable surgical outcome [OR: 3.205 (CI 1.105-9.299), p = 0.032].

CONCLUSION

Symptomatic improvement after pyloroplasty or G-POEM is independent of etiology of gastroparesis, GERD, and primary symptom. Response to dilation or Botox are not markers of response to surgery. However, patients who receive Botox are 3.2 times more likely to improve postoperatively.

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.

Gastric peroral endoscopic pyloromyotomy (G-POEM) in patients with refractory gastroparesis: a review

Gastric peroral endoscopic pyloromyotomy (G-POEM or POP) is an endoscopic therapeutic modality for treatment of refractory gastroparesis. Since the first case reported in 2013, there are more than 200 papers published on G-POEM. In this narrative review, we summarize the short-term and long-term outcomes and review other important studies. The technical success rate is 100% and the short-term (within 1 year) success rate is about 50-80%. The procedure time is between 50 and 70 min while the average length of hospital stay was 2-3 days. The adverse event rate was around 10%. Few patients need further intervention. Three studies showed that at the 4-year follow-up, the response to G-POEM was durable, but there was a yearly recurrence rate of 13% or more. Redo G-POEM is feasible and can be of benefit for some patients. Most of the studies showed that long duration of illness is associated with poor outcomes. However, reliable predictors for successful outcomes are still unknown. Current literature indicates G-POEM is superior to gastric electric stimulator and surgical pyloroplasty. Endoflip has been used at G-POEM to predict the outcome, but the result is very preliminary. A recent sham study confirms the short-term efficacy of G-POEM. G-POEM is safe and about 50% of patients can be discharged to home on the same day. G-POEM allows for direct biopsy of the gastric muscle, which is the location of the pacemaker cells, the interstitial cells of Cajal; therefore, G-POEM may provide a new path for further research on the pathogenesis of gastroparesis.

Submucosal endoscopy: the present and future

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.

Endoscopic clips versus overstitch suturing system device for mucosotomy closure after peroral endoscopic pyloromyotomy (G-POEM): a prospective single-center study

BACKGROUND AND AIMS

G-POEM is an emerging method for treatment of severe gastroparesis. Safe mucosal closure is necessary to avoid adverse events. The aim of this study was to compare the efficacy of two closure methods: clips and endoscopic suturing (ES) after G-POEM.

METHODS

We performed a single center, prospective study. The closure method was assigned at the discretion of an endoscopist prior to the procedure. The main outcome was the proportion of subjects with successful closure. Unsuccessful closure was defined as a need for a rescue method, or a need for an additional intervention or incomplete closure-related adverse events. Secondary outcomes were the easiness of closure (VAS score 1 = very difficult, 10 = easy), closure time, and cost.

RESULTS

A total of 40 patients [21 female; mean age, range 47.5; (20-74)] were included; 20 received ES and 20 clips [mean number of clips 6; range (4-19)]. All 20 patients with ES (100%, 95% CI 84-100%) and 18 patients with clips (89%, 95% CI 70-97%) had successful closure (p = 0.49). One patient needed a rescue method (KING closure) and the other patient an additional clipping on POD1. Closure with clips was quicker [mean time 9.8 (range 4-20) min vs. 14.1 (5-21) min; p = 0.007] and cheaper [mean cost 807 USD (± 402) vs. 2353 USD (± 145); p < 0.001]. Endoscopist assessed the easiness of ES and clips as comparable [mean VAS, range 7.5 (3-10) (ES) vs. 6.9 (3-10) (clips); p = 0.3].

CONCLUSIONS

Both ES and clips are effective methods for mucosal closure in patients undergoing G-POEM. However, centres using clips should have a rescue closure method available as clips may fail in some patients. Closure with ES is more costly than with clips.

Efficacy and safety of endoscopic pyloric balloon dilation in patients with refractory gastroparesis

BACKGROUND AND AIMS

There has been interest in the use of pyloric therapies for the treatment of refractory gastroparesis. However, data on endoscopic pyloric dilation are scarce. We aimed to assess the efficacy and safety of this procedure in refractory gastroparesis.

METHODS

We performed a retrospective analysis of 47 patients referred for refractory gastroparesis, confirmed by gastric emptying scintigraphy, and treated with endoscopic pyloric through-the-scope balloon dilation. The primary endpoint was the effectiveness of the procedure, evaluated with the Gastric Cardinal Symptom Index (GCSI) at 2 and 6 months.

RESULTS

A clinical response, defined by a 1.0 point decrease in the GCSI score, was observed in 25 patients at 2 months (53%) and in 19 patients at 6 months (40%). The mean GCSI score decreased significantly at 2 and 6 months compared to the preoperative score (3.9 ± 0.87 vs 2.3 ± 1.37 and 3.9 ± 0.87 vs 2.9 ± 1.27, respectively; p < 0.0001). No complication was observed. Nine patients had a delayed relapse at 1 year. A second dilation was performed for eight patients and it was effective in five of them (63%). The mean follow-up time of the patients was 27.0 ± 10.4 months. At 2 years, 15 patients still experienced improvement following this treatment (32%). No predictive factor of clinical response was identified.

CONCLUSION

The efficacy of pyloric dilation is 53% at 2 months, with sustained improvement in one third of patients at 2 years. This treatment should be considered as an alternative option to pyloromyotomy.

Evaluation of the safety profile of endoscopic pyloromyotomy by G-POEM: a French multicenter study

BACKGROUND

Gastric per oral endoscopic esophageal myotomy (G-POEM) is a promising procedure to treat refractory gastroparesis. The safety profile of G-POEM is an important topic because gastroparesis is a functional pathology, with a procedure whose effectiveness is between 50 and 65% depending on the studies.

OBJECTIVES

We present this retrospective multicenter study, with the aim of establishing a safety profile, focusing on serious adverse events (AEs).

DESIGN

This was a multicenter observational cohort study conducted in five French expert centers.

METHODS

All patients who underwent G-POEM for refractory gastroparesis between 2015 and 2021 were included for analysis. AEs were classified into per endoscopic, early postoperative, and late postoperative, up to 1 month. Their severity was assessed using Dindo-Clavien and American Society for Gastrointestinal Endoscopy classification. The primary objective was to evaluate the rate of G-POEM severe AEs. Secondary objectives were to document other postoperative AEs, and to identify predictive factors.

RESULTS

In all, 217 patients were included: 81 men and 136 women, mean age 52 ± 17 years. The average procedural time was 44 ± 14 min (12-78). The average hospital stay was 3.7 ± 2.3 days. The AEs rate classified as Clavien-Dindo ⩾3 was 0.4% (one delayed bleeding requiring blood transfusion and endoscopic management). There were no deaths or patients admitted to intensive care unit. The rates of mucosotomy and capnoperitoneum were 3.7 and 1.8%, respectively, without clinical consequences. Most patients (81.5%) did not experience any AE. Three cases of dumping syndrome occurred, quickly managed by dietary measures.

CONCLUSION

Our study confirms the safety of G-POEM with less than 0.5% of serious AEs, medically managed. This outcome makes this a procedure to have a good benefit-risk ratio.

Gastric peroral endoscopic myotomy outcomes after 4 years of follow-up in a large cohort of patients with refractory gastroparesis (with video)

BACKGROUND AND AIMS

Gastric peroral endoscopic myotomy (G-POEM) is used for refractory gastroparesis (RG) with good early-term but variable mid- and long-term outcomes. Limited data exist about candidates and long-term clinical and predictive factors. Our aim was to evaluate the 4-year follow-up efficacy and predictive factors in patients with RG.

METHODS

Confirmed RG patients were included and evaluated between April 2017 and December 2021. Gastroparesis Cardinal Symptom Index (GCSI) score, retention percentage at 4 hours (RP4H), mean half-emptying time (MHET), and the 36-item short-form survey (SF-36) were performed at 1, 6, 12, 18, 24, 30, 36, 42, and 48 months.

RESULTS

After G-POEM, 374 patients with RG were included: 141 patients (37.7%) had diabetic gastroparesis (DG), 115 (30.7%) had idiopathic gastroparesis (IG), 102 (27.3%) had postsurgical gastroparesis (PSG), and 16 (4.3%) had other etiologies. After the 48-month evaluation, 102 patients completed follow-up (DG, 58; IG, 22; PSG, 18; other, 4). Before G-POEM, GCSI score, RP4H, and MHET were 3.84 ± .53, 44% (interquartile range [IQR], 11-68), and 246 minutes (IQR, 150-368), respectively, and after the 48-month evaluation improved to 2.1 ± .70 (P < .001), 15.5% (IQR, 0-36; P = .021), and 135 minutes (IQR, 67-290; P = .045), respectively. At the 48-month evaluation, clinical success was 77.5%. DG showed the best outcomes (DG vs IG vs PSG vs other: 86.5% vs 72.5% [P = .001] vs 72.1% [P = .003] vs 68.8% [P < .001]). Long-term success predictors were DG (odds ratio [OR], 5.113; 95% confidence interval [CI], 1.643-5.981; P = .035), early diagnosis (OR, 2.455; 95% CI, 1.129-3.522; P = .042), nausea/vomiting (OR, 3.541; 95% CI, 1.881-5.511; P = .012), GCSI score at 6 months (1.5-2) (OR, 3.612; 95% CI, 2.122-5.317; P = .022), and RP4H <10% at 6 months (OR, 2.188; 95% CI, 1.435-4.233; P = .039).

CONCLUSIONS

G-POEM is an effective 4-year treatment in patients with RG, especially in DG, establishing a potential first-line therapy in these patients. However, randomized controlled clinical trials are needed to confirm these results. (Clinical trial registration number: NTC03126513.).

Gastric peroral endoscopic myotomy in refractory gastroparesis: long-term outcomes and predictive score to improve patient selection

BACKGROUND AND AIMS

Limited data exist concerning the long-term efficiency of gastric peroral endoscopic myotomy (G-POEM) as a treatment of refractory gastroparesis. This study evaluated the 3-year results of G-POEM in patients with refractory gastroparesis.

METHODS

This was a prospective multicenter study of all G-POEM operations performed in 2 expert French centers for 46 patients with refractory gastroparesis with at least 3 years of follow-up.

RESULTS

Clinical success was 65.2% at 36 months. There was significant improvement in symptom severity. Median Gastroparesis Cardinal Symptom Index decreased from 3.33 to 1.80 (P < .0001), with improvement in all subscales. We created a predictive score concerning G-POEM success (G-POEM predictive score) to which points were assigned as follows: nausea subscale <2: predictive of success, 1 point; satiety subscale >4: predictive of success, 1 point; bloating subscale >3.5: predictive of success, 1 point; percentage of gastric retention at 4 hours on scintigraphy >50%: 1 point. A threshold of 2 was identified by receiver operating characteristic curve analysis with an area under the curve of .825 that predicted clinical success with a sensitivity of 93.3% (95% confidence interval [CI], .77-.99), specificity of 56.3% (95% CI, .33-.77), positive predictive value of 80% (95% CI, .67-.93), negative predictive value of 81.8% (95% CI, .59-1.00), and accuracy of 80.4% (95% CI, .69-.92). Patients with a score ≥2 were significantly more likely to be responders at 3 years than were patients with a score <2 (80% and 18%, respectively; P = .0004).

CONCLUSIONS

The clinical success of G-POEM for refractory gastroparesis was 65.2% at 36 months. Our predictive score offers an easy tool that needs to be confirmed in other studies.

ACG Clinical Guideline: Gastroparesis

Gastroparesis is characterized by symptoms suggesting retention of food in the stomach with objective evidence of delayed gastric emptying in the absence of mechanical obstruction in the gastric outflow. This condition is increasingly encountered in clinical practice. These guidelines summarize perspectives on the risk factors, diagnosis, and management of gastroparesis in adults (including dietary, pharmacological, device, and interventions directed at the pylorus), and they represent the official practice recommendations of the American College of Gastroenterology. The scientific evidence for these guidelines was assessed using the Grading of Recommendations, Assessment, Development, and Evaluation process. When the evidence was not appropriate for Grading of Recommendations, Assessment, Development, and Evaluation, we used expert consensus to develop key concept statements. These guidelines should be considered as preferred but are not the only approaches to these conditions.

Gastric Electrical Stimulation: Role and Clinical Impact on Chronic Nausea and Vomiting

Gastric electrical stimulation (GES) is currently used as an alternative treatment for medically refractory gastroparesis. GES has been initially developed to accelerate gastric motility, in order to relieve the symptoms of the patients. Subsequent studies, unfortunately, failed to demonstrate the acceleration of gastric emptying using high-frequency stimulation – low energy stimulation although the technique has shown a clinical impact with a reduction of nausea and vomiting for patients with gastroparesis. The present review details the clinical efficacy of GES in gastroparesis as well as its putative mechanisms of action.

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.

Systematic review with meta-analysis: one-year outcomes of gastric peroral endoscopic myotomy for refractory gastroparesis

BACKGROUND

Several studies have examined the efficacy of gastric peroral endoscopic myotomy (G-POEM) for gastroparesis.

AIM

To evaluate the mid-term efficacy of G-POEM by meta-analysis of studies with a minimum 1 year of follow-up.

METHODS

We reviewed several databases from inception to 10 June 2021 to identify studies that evaluated the efficacy of G-POEM in refractory gastroparesis, and had at least 1 year of follow-up. Our outcomes of interest were clinical success at 1 year, adverse events, difference in mean pre- and 1 year post-procedure Gastroparesis Cardinal Symptom Index (GCSI) score, and difference in mean pre- and post-procedure EndoFLIP measurements. We analysed data using a random-effects model and assessed heterogeneity by I2 statistic.

RESULTS

We included 10 studies comprising 482 patients. Pooled rates (95% CI) of clinical success at 1 year and adverse events were 61% (49%, 71%) and 8% (6%, 11%), respectively. Mean GCSI at 1 year post-procedure was significantly lower than pre-procedure; mean difference (MD) (95% CI) -1.4 (-1.9, -0.9). Mean post-procedure distensibility index was significantly higher than pre-procedure in the clinical success group at 40 and 50 mL volume distension; standardised mean difference (95% CI) 0.82 (0.07, 1.64) and 0.91 (0.32, 1.49), respectively. In the clinical failure group, there was no significant difference between mean pre- and post-procedure EndoFLIP measurements.

CONCLUSIONS

G-POEM is associated with modest clinical success at 1 year. Additional studies with longer follow-up are required to evaluate its longer-term efficacy.

Third-Space Endoscopy: Recent Updates

Third space or submucosal space is a potential space which on expansion allows the endoscopist to execute a multitude of therapeutic procedures for various gastrointestinal diseases like achalasia, subepithelial tumors, Zenker’s diverticulum, and refractory gastroparesis. Third space was first utilized for performing endoscopic myotomy in cases with achalasia cardia about a decade ago. Since then, the field of submucosal endoscopy has witnessed an exponential growth. The present review focuses on recent advances in the field of third-space endoscopy. With regard to per-oral endoscopic myotomy (POEM) in achalasia cardia, several recent studies have evaluated the long-term outcomes of POEM, compared endoscopic myotomy with pneumatic dilatation (PD) and surgical myotomy, and evaluated the outcomes of short- versus long-esophageal myotomy. In addition, the utility of multiple dose antibiotic prophylaxis to prevent infections after POEM has been questioned. Overall, the results from these studies indicate that POEM is a durable treatment modality, equally effective to Heller’s myotomy and superior to PD. With regard to gastric-POEM (G-POEM), recent studies suggest only modest efficacy in cases with refractory gastroparesis. Therefore, quality studies are required to identify predictors of response to optimize the outcomes of G-POEM in these cases. Another third-space endoscopy procedure that has gained popularity is endoscopic division of septum in cases with esophageal diverticula including Zenker’s POEM and epiphrenic diverticula POEM (Z-POEM and D-POEM, respectively). The technique of diverticulotomy using the principles of submucosal endoscopy appears safe and effective in short term. Data on term outcomes are awaited and comparative trials with flexible endoscopic myotomy required. Per-rectal endoscopic myotomy (PREM) is the most recent addition to third space endoscopy procedures for the management of short-segment Hirschsprung’s disease. Limited data suggest that PREM may be a promising alternative surgery in these cases. However, quality studies with long-term follow-up are required to validate the outcomes of PREM.

[G-POEM - Gastric Peroral Endoscopic Myotomy as a Therapy Option for Chronic Gastric Emptying Disorders]

Many doctors and patients shy away from the surgical intervention of a pyloromyotomy using laparoscopy. The effectiveness of botulinum toxin injections into the pylorus has not been established 1 2. Pharmacological therapeutic approaches are unsatisfactory and show a wide range of side effects 3. G-POEM is a procedure that has proven its feasibility with a low complication rate. A relatively high response could be documented in previous publications 4. The long-term successes are still being discussed controversially 5. After the initial euphoria, the problem of patient selection comes to the fore. The symptoms, as well as the pathophysiology of gastric emptying disorder, are diverse 6. The diagnostic tests available do not reflect the variability of the disease 7 8 9 10. The postoperative gastric emptying disorder seems to be an exception. G-POEM can protect both therapists and patients from another invasive procedure.

Navigational tunnel technique for gastric peroral endoscopic pyloromyotomy: getting straight to the point (pylorus)

Background and Aims

Gastric peroral endoscopic pyloromyotomy (G-POEM) is emerging as a treatment option for patients with gastroparesis. The most technically difficult part of the procedure is creating a submucosal tunnel in the gastric antrum, which can be directionally challenging. We describe a novel navigational tunneling method that guides submucosal dissection in the direction of the pylorus and helps to identify the pyloric landmarks.

Methods

Consecutive patients from September to December 2020 who underwent G-POEM for symptomatic gastroparesis were included. All cases were confirmed by prolonged gastric emptying study. The navigational tunnel technique was performed as follows: (1) mucosal cautery markings were made to outline the tunnel starting 3 to 4 cm proximal to the pylorus, (2) submucosal injection was done at the level of the pylorus and extended backward to the incision point, and (3) submucosal dissection was carried out after the prior submucosal injection straight to the pylorus.

Results

Six patients with gastroparesis underwent G-POEM with the navigational tunneling technique. The average time for submucosal injection was 2 minutes and 42 seconds, and the average tunnel time was 15 minutes and 36 seconds. There were no adverse events. All patients reported significant improvement (50%-85%) in symptoms.

Conclusions

This novel navigational tunneling technique appears to guide and facilitate G-POEM by providing a visual path for submucosal dissection straight to the pylorus. It may increase efficiency, decreasing the need to repeatedly exit the tunnel to check direction and preventing nonproductive wandering. It may also help identify the pyloric ring within the tunnel.

Third space endoscopy: the future of treating gastrointestinal dysmotility

PURPOSE OF REVIEW

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.

RECENT FINDINGS

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.

SUMMARY

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.

Gastric peroral endoscopic myotomy for the treatment of refractory gastroparesis: a prospective single-center experience with mid-term follow-up (with video)

BACKGROUND AND AIMS

Gastroparesis (GP) is a multifactorial disease associated with a large burden on the health care systems. Pyloric-directed therapies including gastric peroral endoscopic myotomy (G-POEM) can be effective in improving patient quality of life and symptom severity. We report on the safety and efficacy of G-POEM and its impact on the quality of life of patients managed at a large referral center.

METHODS

Consecutive patients with confirmed GP referred for G-POEM due to failure of medical therapy were included. All patients were assessed at baseline and then at 1, 3, 6, and 12 and 24 months after G-POEM using validated symptom and quality of life instruments, including the Gastroparesis Cardinal Symptom Index (GCSI), Patient Assessment of Gastrointestinal Disorders Symptom Severity Index (PAGI-SYM), and 36-Item Short Form Survey (SF-36). Patients were evaluated before and 6 months after the procedure with EGD, 4-hour scintigraphy, and pyloric EndoFLIP. Technical success was defined as the ability to perform full-thickness pyloromyotomy. Clinical response was defined as an improvement of ≥1 point on GCSI.

RESULTS

Fifty-two patients (median age, 48 years; range, 25-80 years, 88% female) underwent G-POEM between February 2018 and September 2020 for the following phenotypes: vomiting-predominant (n=30), dyspepsia-predominant (n=16), and regurgitation-predominant (n=6) GP. The technical success rate was 100%. Adverse events were noted in 3 of 52 patients (5.77%), and were all managed successfully endoscopically. Clinical response was achieved in 68%, 58%, and 48% of patients at 1-month, 6-month, and 12-month follow-up (P < .001, P < .001, and P < .01, respectively). When classified by the cause of GP, the clinical response rates were diabetic GP 64% (11 of 17), postsurgical GP 67% (6 of 9), and idiopathic GP 72% (13 of 18). A statistically significant improvement in PAGI-SYM scores was observed at 1, 3, 6, 12, and 24 months, in addition to significant improvement in several domains of SF-36. Mean 4-hour gastric emptying was reduced 6 months after G-POEM (10.2%) compared with baseline (36.5%, P < .001). We report a significant reduction in the number of emergency department visits and days spent in the hospital up to 24 months after G-POEM.

CONCLUSIONS

G-POEM appears to be a safe and feasible treatment alternative for refractory GP with significant short-term and mid-term improvements in overall symptoms, quality of life scores, and health care utilization.