Per-oral Pyloromyotomy (POP) for Medically Refractory Gastroparesis: Short Term Results From the First 100 Patients at a High Volume Center

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.

Invasive acupuncture for gastroparesis after thoracic or abdominal surgery: a systematic review and meta-analysis

OBJECTIVES

This meta-analysis aimed to systematically evaluate the efficacy of acupuncture in treating postsurgical gastroparesis syndrome (PGS) after thoracic or abdominal surgery.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

Twelve databases (PubMed, Embase, Cochrane Library Cochrane Central Register of Controlled Trials (CENTRAL), Medline (Ovid) (from 1946), Web of Science, EBSCO, Scopus, Open Grey, China National Knowledge Infrastructure (CNKI), Wanfang Database, Chinese Scientific Journals Database (VIP) and China Biology Medicine disc (CBM)) and three registration websites (WHO International Clinical Trials Registry Platform (ICTRP), ClinicalTrials.gov, and Chinese Clinical Trial Registry (ChiCTR)) were searched from the inception to September 2022, and citations of the included literature were screened.

ELIGIBILITY CRITERIA

All randomised controlled trials addressing invasive acupuncture for PGS.

DATA EXTRACTION AND SYNTHESIS

Key information on the included studies was extracted by two reviewers independently. Risk ratio (RR) with 95% CI was used for categorical data, and mean difference with 95% CI for continuous data. The quality of evidence was assessed using Grading of Recommendations Assessment, Development and Evaluation. Outcomes were conducted with trial sequential analysis (TSA).

RESULTS

Fifteen studies with 759 patients met the inclusion criteria. Subgroup analyses revealed that compared with the drug group, the drug and acupuncture group had a greater positive effect on the total effective rate (TER) (nine trials, n=427; RR=1.20; 95% CI 1.08 to 1.32; P-heterogeneity=0.20, I2=28%, p=0.0004) and the recovery rate (RCR) (six trials, n = 294; RR = 1.61; 95% CI 1.30 to 1.98; P-heterogeneity=0.29, I2=19%, p<0.0001) of PGS after abdominal surgery. However, acupuncture showed no significant advantages in terms of the TER after thoracic surgery (one trial, p=0.13) or thoracic/abdominal surgery-related PGS (two trials, n = 115; RR=1.18; 95% CI 0.89 to 1.57; P-heterogeneity=0.08, I2=67%, p=0.24) and the RCR after thoracic/abdominal surgery (two trials, n=115; RR=1.40; 95% CI 0.97 to 2.01; P-heterogeneity=0.96, I2=0%, p=0.07). The quality of evidence for TER and RCR was moderate certainty. Only one study reported an acupuncture-related adverse event, in the form of mild local subcutaneous haemorrhage and pain that recovered spontaneously. TSA indicated that outcomes reached a necessary effect size except for clinical symptom score.

CONCLUSION

Based on subgroup analysis, compared with the drug treatment, acupuncture combined drug has significant advantages in the treatment of PGS associated with abdominal surgery, but not with thoracic surgery.

PROSPERO REGISTRATION NUMBER

CRD42022299189.

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.

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.

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.

Gastroparesis with concomitant gastrointestinal dysmotility is not a contraindication for per-oral pyloromyotomy (POP)

INTRODUCTION

Per-oral pyloromyotomy (POP or G-POEM) provides significant short-term improvements in symptoms and objective emptying for patients with medically refractory gastroparesis, but it is unclear if patients with gastroparesis and co-existing dysmotility (small bowel or colonic delay) also benefit. In this study, we used wireless motility capsule (WMC) data to measure outcomes in patients with isolated gastroparesis (GP) and gastroparesis with co-existing dysmotility (GP + Dys) who underwent POP.

METHODS

We retrospectively analyzed patients who had POP and completed WMC data during their evaluation of intestinal dysmotility. WMC data were reviewed to identify patients who demonstrated isolated GP or GP + Dys. Each patient's pre-op and post-op Gastroparesis Cardinal Symptom Index (GCSI) and 4-h solid-phase scintigraphy gastric emptying studies (GES) scores were compared to evaluate improvement.

RESULTS

Of the entire cohort (n = 73), 89% were female with a mean age of 47.0 ± 15.0 years old. Gastroparesis etiologies were divided among idiopathic (54.8%), diabetic (26%), postsurgical (8.2%), autoimmune (5.5%), and multifactorial (5.5%). Forty-one patients (56%) had GP and 32 patients (44%) had GP + Dys. GCSI improved after POP whether the patient had isolated GP (- 12.31, p < 0.001) or GP + Dys (- 9.58, p < 0.001); however, there was no significant difference in total GCSI improvement between the two groups. A subset of patients had postoperative GES available (n = 47). In the isolated GP and GP + Dys cohorts, 15/28 (54%) and 12/19 (63%) patients had normal post-op 4-h GES, respectively, but no statistical difference between the two groups.

CONCLUSION

Patients with medically refractory gastroparesis with and without concomitant gastrointestinal dysmotility show short-term subjective and objective improvement after POP. Concomitant small bowel or colonic dysmotility should not deter physicians from offering POP in carefully selected patients with gastroparesis.

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.

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.

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

BACKGROUND

Data on the long-term outcomes of gastric peroral endoscopic myotomy (G-POEM) for refractory gastroparesis are lacking. We report the results of a large multicenter long-term follow-up study of G-POEM for refractory gastroparesis.

METHODS

This was a retrospective multicenter study of all G-POEM operations performed in seven expert French centers for refractory gastroparesis with at least 1 year of follow-up. The primary endpoint was the 1-year clinical success rate, defined as at least a 1-point improvement in the Gastroparesis Cardinal Symptom Index (GCSI).

RESULTS

76 patients were included (60.5 % women; age 56 years). The median symptom duration was 48 months. The median gastric retention at 4 hours (H4) before G-POEM was 45 % (interquartile range [IQR] 29 % - 67 %). The median GCSI before G-POEM was 3.6 (IQR 2.8 - 4.0). Clinical success was achieved in 65.8 % of the patients at 1 year, with a median rate of reduction in the GCSI score of 41 %. In logistic regression analysis, only a high preoperative GCSI satiety subscale score was predictive of clinical success (odds ratio [OR] 3.41, 95 % confidence interval [CI] 1.01 - 11.54; P = 0.048), while a high rate of gastric retention at H4 was significantly associated with clinical failure (OR 0.97, 95 %CI 0.95 - 1.00; P = 0.03).

CONCLUSIONS

The results confirm the efficacy of G-POEM for the treatment of refractory gastroparesis, as evidenced by a 65.8 % clinical success rate at 1 year. Although G-POEM is promising, prospective sham-controlled trials are urgently needed to confirm its efficacy and identify the patient populations who will benefit most from this procedure.

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.

Gastric peroral endoscopic pyloromyotomy for decompensated gastroparesis: comprehensive motility analysis in relation to treatment outcomes

Background and study aims  There are no reliable data to predict which patients with gastroparesis (GP) would benefit the most from gastric peroral endoscopic pyloromyotomy (G-POEM). The aim of the present study was to assess whether antro-duodenal motility patterns and pyloric distensibility can predict the outcome of G-POEM in patients with decompensated GP. Patients and methods  In an open-label study, patients with GP and refractory symptoms were eligible for treatment with G-POEM if treatment attempts according to a standardized stepwise protocol had failed. Baseline assessment included Gastroparesis Cardinal Symptom Index (GCSI), C13-octanoic gastric emptying breath test and high-resolution antro-duodenal manometry. Pyloric distensibility using EndoFlip measurements was assessed at baseline and 3 months after the procedure. Explorative analyses were performed on potential predictors of response using logistic regression analyses. Results  Twenty-four patients with decompensated GP underwent G-POEM. At baseline, 78.3 % and 61.9 % of patients showed antral hypomotility and neuropathic motor patterns, respectively. The technical success rate was 100 % (24/24). Mean GCSI improved significantly at 3, 6, and 12 months after G-POEM ( P  = 0.01). Median distensibility index (DI) improved significantly as compared with baseline (7.5 [6.9;11.7] vs. 5.3[3.1;8.1], P  = 0.004). A significant correlation was found between clinical response at 6 months and pyloric DI improvement ( P  = 0.003). No potential predictors of clinical response after G-POEM could be identified in an explorative analysis. Conclusions  G-POEM improved pyloric distensibility patterns in patients with decompensated GP. Clinical response at 6 months after G-POEM was associated with pyloric distensibility improvement. However, no potential predictors of response could be identified from either antro-duodenal motility patterns or pyloric distensibility.

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.

Recent advances in third space or intramural endoscopy

Third space endoscopy or intramural endoscopy is based on the principle that the deeper layers of the gastrointestinal tract can be accessed by tunneling in the submucosal space and maintaining the integrity of the overlying mucosa. The era of third space endoscopy started with peroral endoscopic myotomy (POEM) for treatment of achalasia and has expanded to treat various other gastrointestinal disorders. The technique is also currently used for treatment of refractory gastroparesis, Zenker’s diverticulum (ZD), resection of subepithelial tumors and early cancers of the gastrointestinal tract and Hirschsprung’s disease (HD). These procedures are rapidly emerging as minimally invasive alternatives to conventional surgery. They are safe and effective with excellent outcomes. This review focuses on the evolution and current applications of third space endoscopy in various gastrointestinal disorders. Key points: (1) Third space or intramural endoscopy initially started with the POEM procedure for treatment of achalasia; (2) Advancements in procedural techniques have expanded its application to treat other gastrointestinal disorders such as refractory gastroparesis, ZD, HD, resection of subepithelial tumors and early gastrointestinal cancers; (3) These procedures are highly effective with excellent outcomes and low complication rates; and (4) Third space endoscopic procedures are rapidly emerging as minimally invasive alternatives to conventional surgery.

Peroral Pyloromyotomy

Peroral pyloromyotomy, an innovative intramural endoscopic surgery procedure, is a successful management option for appropriately selected patients who suffer from medically refractory gastroparesis. Gastroparesis is a debilitating disorder of the gastrointestinal tract, which significantly decreases quality of life and overall survival. This article describes the history and background, the indications for, the diagnosis of, and the preparation, technique, and short-term outcomes of peroral pyloromyotomy.

Principles of Intramural Surgery

Intramural surgery is a minimally invasive surgical technique based on flexible endoscopy. The first step involves the initial mucosal incision for entry point. Then a submucosal tunnel is dissected to the site of the target anatomy. The procedure performed may include myotomy or lesion removal. When complete, the initial mucosal incision is closed. This technique separates the mucosal flap from the surgical site, minimizing the risk of full-thickness perforation and gastrointestinal leakage. Peroral endoscopic myotomy is the most studied application of intramural surgery but other procedures have emerged. This article explores principles of intramural surgery and summarizes its applications.

Endoscopic Equipment-From Simple to Advanced

Flexible endoscopic procedures, such as esophagogastroduodenoscopies and colonoscopies, allow for diagnosis and treatment of numerous gastrointestinal disorders. Advanced endoscopic procedures, such as endoscopic ultrasounds, endoscopic retrograde cholangiopancreatography, and balloon enteroscopies, offer therapeutic options that are minimally invasive and effective. As technology advances, the equipment and tools in an endoscopist's armamentarium continue to grow. This article highlights key endoscopic equipment and supplies, from simple to advanced.

A History of Flexible Gastrointestinal Endoscopy

Surgeons have been involved, since the beginning, in the development and evolution of endoscopy. They have been instrumental in developing new methods and have been actively involved in most of the therapeutic applications. The continued evolution of endoscopic technique is inevitable and will involve the integration of new technology with innovative thinking.

Per Oral Pyloromyotomy for Gastroparesis: A Systematic Review of the Current Literature and Future Recommendations

Background: Gastric per oral endoscopic myotomy (GPOEM) was developed as a therapeutic option for gastroparesis after the pylorus was identified as a key target for gastroparesis management. This study includes a systematic literature review of studies in which GPOEM was utilized as therapy for gastroparesis. Methods: A literature search was conducted in three databases (MEDLINE, Scopus and Embase) of articles that included the keywords “GPOEM”, “Gastric per oral endoscopy myotomy” or “per oral pyloromyotomy” and “Gastroparesis” in the abstract or title. The search covered articles published until 29 February 2020. Results: A total of 139 articles were identified. Only 15 articles met the final inclusion criteria and were retrieved for qualitative data synthesis. Conclusion: GPOEM for gastroparesis is shown to have a high success rate among the studies but data interpretations are limited because of small sample sizes and short follow-up. Subjective and objective data prior to and post-GPOEM will be mandatory to establish credibility. The procedure is technically feasible and safe based on the limited studies available.

Techniques and devices for the endoscopic treatment of gastroparesis (with video)

BACKGROUND AND AIMS

Gastroparesis is a symptomatic chronic disorder of the stomach characterized by delayed gastric emptying in the absence of mechanical obstruction. Several endoscopic treatment modalities have been described that aim to improve gastric emptying and/or symptoms associated with gastroparesis refractory to dietary and pharmacologic management.

METHODS

In this report we review devices and techniques for endoscopic treatment of gastroparesis, the evidence regarding their efficacy and safety, and the financial considerations for their use.

RESULTS

Endoscopic modalities for treatment of gastroparesis can be broadly categorized into pyloric, nonpyloric, and nutritional therapies. Pyloric therapies such as botulinum toxin injection, stent placement, pyloroplasty, and pyloromyotomy specifically focus on pylorospasm as a therapeutic target. These interventions aim to reduce the pressure gradient across the pyloric sphincter, with a resultant improvement in gastric emptying. Nonpyloric therapies, such as venting gastrostomy and gastric electrical stimulation, are intended to improve symptoms. Nutritional therapies, such as feeding tube placement, aim to provide nutritional support.

CONCLUSIONS

Several endoscopic interventions have shown utility in improving the quality of life and symptoms of select patients with refractory gastroparesis. Methods to identify which patients are best suited for a specific treatment are not well established. Endoscopic pyloromyotomy is a relatively recent development that may prove to be the preferred pyloric-directed intervention, although additional and longer-term outcomes are needed.

Targeting Treatment of Gastroparesis: Use of Clinical Tests to Guide Treatments

Gastroparesis presents with nausea, vomiting, and other upper gut symptoms, and is diagnosed by confirming delayed gastric emptying. A related condition, chronic unexplained nausea and vomiting, has similar symptoms but with normal emptying. Both conditions are managed using therapies with diverse mechanisms of action. Even though prokinetic treatments are proposed to improve gastroparesis by accelerating gastric emptying, there is limited evidence that they provide benefit by virtue of transit stimulating effects. Other tests can delineate alterations in other gut sensorimotor parameters in patients with suspected gastroparesis, but their relation to symptoms and their capability to guide treatment are largely unproved.

Peroral endoscopic pyloromyotomy for gastroparesis: a systematic review and meta-analysis

Background and aim  Gastric peroral endoscopic pyloromyotomy (G-POEM) is a new therapeutic option for refractory gastroparesis (GP). A systematic review and meta-analysis was conducted to assess the effectiveness of G-POEM in refractory GP. For the quality of evidence, we used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) criteria. Methods  We performed a literature search using MEDLINE, Embase, Cochrane library, LILACS and the Science citation index for studies related to G-POEM from the inception of its technique through January 2019. We selected studies that analyzed the gastroparesis cardinal symptom index (GCSI) and 4-hour solid-phase gastric emptying scintigraphy (GES) before and after the procedure to verify the efficacy of G-POEM, the main outcome measured. An analysis was performed using RevMan 5.3. Results  Ten studies comprising 281 patients were included in this systematic review. The pooled mean difference in GCSI following the procedure was 1.76 (95 % CI: [1.43, 2.08], I ²  = 72 %). We also performed GCSI subgroup analysis by follow-up duration that showed a pooled mean difference of 1.84 (95 % CI: [1.57, 2.12], I ²  = 71 %). The pooled mean difference in GES after the procedure was 26.28 (95 % CI: [19.74, 32.83], I ²  = 87 %), corresponding to a significant drop in percentage values of the gastric retention 4-hour scintigraphy. Conclusion  This meta-analysis demonstrates that G-POEM is effective and shows promising outcomes in the clinical response and gastric emptying scintigraphy for gastroparesis. Therefore, it should be considered in the management of refractory gastroparesis.

Pathophysiology, Aetiology and Treatment of Gastroparesis

Gastroparesis is characterized by delayed gastric emptying, with symptoms such as nausea, vomiting and abdominal pain, in the absence of mechanical obstruction. In most cases, it is idiopathic although diabetes mellitus is another leading cause. The physiology of gastric emptying is a complex process which is influenced by various inputs including the central nervous system, enteric nervous system and gut hormones. Developments in our understanding of gastroparesis have now demonstrated dysfunction in these systems, thus disrupting normal gastric emptying. Once mechanical obstruction is excluded, gastric scintigraphy remains the gold standard for diagnosis although wireless motility capsule and breath testing are alternative methods for diagnosis. Treatment for gastroparesis is challenging, and widely available therapies are often limited either by their poor evidence for efficacy or concerns over their long-term safety profile. Novel prokinetic agents have shown initial promise in clinical trials, and new endoscopic techniques such as gastric per-oral endoscopic myotomy are emerging. These new treatment modalities may provide an option in refractory gastroparesis with the adage of reduced morbidity compared to surgical treatments.

Gastric peroral endoscopic pyloromyotomy for refractory gastroparesis: a systematic review of early outcomes with pooled analysis

BACKGROUND AND AIMS

Gastroparesis (GP) is a chronic debilitating condition. Prior pyloric-targeted procedures are either invasive or have questionable efficacy. Gastric peroral pyloromyotomy (G-POEM) has been proposed as a minimally invasive approach. We performed a pooled analysis to evaluate the efficacy and safety of G-POEM for GP.

METHODS

Electronic databases (Medline, Scopus, EMBASE) were searched up to January 2019. Studies including patients who underwent G-POEM for GP were eligible. Procedural, clinical, and safety outcomes were assessed by pooling data with a random- or fixed-effect model according to the degree of heterogeneity to obtain a proportion with a 95% confidence interval.

RESULTS

Ten studies were eligible for inclusion (292 patients), and 2 of the 10 studies were prospective. Seven studies were performed in the United States, 2 in France, and 1 in China. Endoscopic pyloromyotomy was feasible in all patients. Significant symptomatic improvement was achieved after 83.9% of procedures (mean follow-up, 7.8 ± 5.5 months). When comparing the mean values of pre- and postprocedural scintigraphic evolution, there was a significant decrease of the residual percentage at 2 and 4 hours. The overall adverse events rate was 6.8%.

CONCLUSIONS

G-POEM appears to be a promising approach for GP in terms of safety and efficacy outcomes in the short term.

Gastric per-oral endoscopic myotomy (G-POEM) is a promising treatment for refractory gastroparesis: a systematic review and meta-analysis

AIM

to evaluate the efficacy and safety of gastric per-oral endoscopic myotomy (G-POEM) for the treatment of refractory gastroparesis.

METHODS

PubMed, Embase and Cochrane databases were searched and used for study inclusion. Clinical studies since January 2013 to October 2019 were identified as suitable for inclusion. Conference papers, review articles, case reports, animal studies, letters, studies with repetitive data, studies that did not mention the Gastroparesis Cardinal Symptom Index (GCSI) score/gastric emptying scintigraphy (GES) hours or were not indicated in the standard form were excluded. GCSI score, GCSI reduction, gastric emptying scintigraphy at four hours (GES-4h) and GES time (GET) reduction were considered as major indexes and the meta-analysis was achieved using Review Manager 5.3. Research bias was measured according to Cochrane handbook.

RESULTS

nine studies were included with a total of 235 patients that underwent G-POEM, and the technical success rate was 100%. After G-POEM, patients reported changes in GCSI score (6/9 studies, mean difference 1.41 [CI: 0.93, 1.88], p < 0.0001), GCSI reduction (8/9 studies, odds ratio 3.00 [CI: 2.24, 4.03], p < 0.0001), GES-4h (8/9 studies, mean difference 23.78 [CI: 19.88, 27.68], p < 0.00001) and GET reduction (6/9 studies, odds ratio 3.50 [CI: 2.12, 5.78], p < 0.00001). The intra-procedure complication rate was 5.1% (12/235), including capnoperitoneum (seven cases) and accidental mucotomy (five cases). The post-procedure complication rate was 6.8% (16/235), including abdominal pain (three cases), bleeding (three cases), ulcer (one case), difficulty swallowing (one case) and others (eight cases). Both per- and post-procedure complications were easily managed by conservative or endoscopic treatments.

CONCLUSION

the results show that gastroparesis patients can benefit from G-POEM, the success rate was impressive and the complication rate was relatively low. However, caution is necessary when interpreting the results, primarily due to the limitations of uncontrolled studies. Randomized control studies are still needed for further evaluations.

Sleeve gastrectomy for treatment of delayed gastric emptying-indications, technique, and results

INTRODUCTION

Delayed gastric emptying (DGE) can be caused by gastric motility disorders such as gastroparesis with idiopathic background, diabetic neuropathy, or postsurgical nerve damage. Currently, a variety of endoscopic and surgical treatment options are available. We noted clinical improvement of gastric emptying with reduction of the gastric fundus following both fundoplication and fundectomy. As a consequence, we explored the effect of sleeve gastrectomy on gastric emptying. The focus of this paper is to investigate the role of laparoscopic sleeve gastrectomy (LSG) in the treatment of gastroparesis.

METHODS

Patients with symptoms suggestive of gastroparesis received diagnostic work-up (gastric emptying scintigraphy and/or Radiographic Barium-Sandwich Emptying studies). Patients with fundic emptying problems and moderate gastric dilation were selected for a LSG. All perioperative parameters were documented regarding patients characteristics, complications, and outcomes expressed as symptoms and quality of life (GIQLI gastrointestinal quality of life index). Assessment of DGE: Barium Emptying Radigraphy Index (BERI) 0-5.

RESULTS

From 122 patients with gastroparesis, 19 patients were selected for LSG (mean age 54 years (23-68); 10 males/9 females. Morbidity 2/19; no mortality; follow-up mean 24 months (12-60); preop/postop: BERI: 2, 31/1, 27 (p < 0.01); we noted significant improvement of the quality of life (preoperative GIQLI 78 (44-89)) to postoperative values of 114 (range 87-120) (p < 0.0001). Preoperative median BMI of these 19 patients was 24 [1-10], which was not significantly changed in the 15 patients at > 1 year follow-up with 23 [1-8]. Postoperative recurrence of DGE occurred in 3 patients who were reoperated after >1 year follow-up.

CONCLUSION

LSG is a potential surgical treatment option for selected patients with gastroparesis and fundic emptying problems.

Safety and Feasibility of Per-Oral Pyloromyotomy as Augmentative Therapy after Prior Gastric Electrical Stimulation for Gastroparesis

BACKGROUND

For medically refractory diabetic or idiopathic gastroparesis, gastric electrical stimulation (GES) is an excellent option for symptom control; however, a small subset of patients may develop recurrent or persistent symptoms. Per-oral pyloromyotomy (POP, also described by some authors as gastric per-oral endoscopic myotomy or G-POEM) is an emerging therapy for medically refractory gastroparesis. This study investigated the safety and feasibility of POP after previous GES for recurrent or persistent gastroparesis.

STUDY DESIGN

We retrospectively identified all patients undergoing POP between January 2016 and December 2017, with GES in situ. Patient characteristics, gastroparesis etiology, and procedural data were collected. Symptoms were assessed with the Gastroparesis Cardinal Symptom Index (GCSI) both before and 30 to 90 days after POP. Standard pre- and post-procedure 4-hour gastric emptying tests were obtained when available.

RESULTS

There were 22 patients who met inclusion criteria (81.8% female, mean age 42.3 ± 12.4 years). Causes of gastroparesis were diabetes in 38.1%, and idiopathic in 61.9%. The average time since GES insertion was 3.45 years. Mean preoperative 4-hour gastric retention was 50.1%. Most POP procedures were performed in the operating room (90.9%), with mean operative time of 40 minutes and a 1.4-day length of stay. There were 4 readmissions within 30 days, but no POP-related complications. Overall, GCSI improved by an absolute reduction of 1.63 points (p = 0.002), with significant improvements in all sub-scores. Of 11 patients with post-procedural motility or emptying studies available, 7 were normal.

CONCLUSIONS

Per-oral pyloromyotomy appears to be safe and feasible for patients with recurrent gastroparesis symptoms after GES. Both symptoms and motility significantly improved in the short-term. These data replicate similar data suggesting laparoscopic pyloroplasty as an effective augmentative therapy after GES, but may provide a less invasive option for patients.

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.

Endoscopic techniques for myotomy of the lower esophageal sphincter and pylorus

PURPOSE OF REVIEW

Peroral endoscopic myotomy (POEM) and gastric peroral endoscopic myotomy (G-POEM) are minimally invasive endoscopic procedures for the treatment of esophageal motility disorders and refractory gastroparesis, respectively. In this review, we highlight the most recent publications on the technical aspects of POEM and G-POEM.

RECENT FINDINGS

POEM has evolved into a standard therapeutic option in patients with all achalasia subtypes with excellent durability and safety profile. G-POEM is a novel endoscopic procedure with promising results in terms of efficacy, safety, and symptom improvement in patients with refractory gastroparesis.

SUMMARY

POEM and G-POEM are novel endoscopic procedures. Practice patterns vary among endoscopists and procedure techniques continue to evolve. Comparative studies examining outcomes of different techniques are needed.

Gastrectomy versus stomach left in situ with Roux-en-Y reconstruction for the treatment of gastroparesis

BACKGROUND

Gastroparesis is a debilitating functional disorder of the stomach marked by delayed gastric emptying in the absence of mechanical obstruction. Patients with severe, refractory symptoms may ultimately be managed with Roux-en-Y reconstruction; however, it is unclear whether the stomach should be left in situ, similar to a conventional gastric bypass, or resected as in gastrectomy.

METHODS

All patients undergoing Roux-en-Y for the treatment of gastroparesis (GP) at our institution from September 2010 through March 2018 were retrospectively reviewed. Patients with prior gastric resection or whose primary operative indication was not gastroparesis were excluded from analysis.

RESULTS

Twenty-six patients underwent Roux-en-Y with stomach left in situ (RY-SIS) and twenty-seven patients underwent gastrectomy with Roux-en-Y reconstruction during the study period. The mean age was 49.7 years in the RY-SIS cohort and 48.5 years in the gastrectomy cohort. Etiology of GP was similar between the two cohorts. Patients undergoing gastrectomy were more likely to have previous interventions for GP (63.0% vs. 26.9%). RY-SIS was associated with a shorter operative time (155 vs. 223 min), less blood loss (24 vs. 130 mL), and shorter length of stay (4.0 vs. 7.2 days). Twelve patients (44.4%) had complications within 30 days following gastrectomy compared to two patients (7.7%) following RY-SIS (p = 0.001). Patients in the RY-SIS cohort were more likely to require further subsequent surgical intervention for GP (23.1% vs. 3.7%, p = 0.04). At last follow-up, there were no differences in reported GP symptoms or symptom scoring.

CONCLUSIONS

Gastrectomy was associated with greater perioperative morbidity compared to leaving the stomach in situ. Symptomatic improvement at intermediate follow-up was equivalent following either procedure. However, patients undergoing RY-SIS were more likely to require subsequent surgical intervention, suggesting that gastrectomy may be a more definitive operation for the management of medically refractory gastroparesis.

Gastric per-oral endoscopic myotomy: Current status and future directions

Gastroparesis, or symptomatic delayed gastric emptying in the absence of mechanical obstruction, is a challenging and increasingly identified syndrome. Medical options are limited and the only medication approved by the Food and Drug Administration for treatment of gastroparesis is metoclopramide, although other agents are frequently used off label. With this caveat, first-line treatments for gastroparesis include dietary modifications, antiemetics and promotility agents, although these therapies are limited by suboptimal efficacy and significant medication side effects. Treatment of patients that fail first-line treatments represents a significant therapeutic challenge. Recent advances in endoscopic techniques have led to the development of a promising novel endoscopic therapy for gastroparesis via endoscopic pyloromyotomy, also referred to as gastric per-oral endoscopic myotomy or per-oral endoscopic pyloromyotomy. The aim of this article is to review the technical aspects of the per-oral endoscopic myotomy procedure for the treatment of gastroparesis, provide an overview of the currently published literature, and outline potential next directions for the field.

Per-Oral Pyloromyotomy (POP) for Medically Refractory Post-Surgical Gastroparesis

BACKGROUND

Post-surgical gastroparesis (psGP) is putatively related to vagal denervation from either therapeutic transection or inadvertent injury. Here, we present a series of patients undergoing endoscopic per-oral pyloromyotomy (POP) as a treatment for medically refractory psGP.

METHODS

Patients identified from a prospectively maintained database of patients undergoing POP procedures at our institution from January 2016 to January 2018 were included. Surgical history, symptom scores, and gastric emptying studies before and 3 months after POP were additionally recorded.

RESULTS

During the study period, 177 POP procedures were performed, of which 38 (21.5%) were for psGP. The study cohort was 84.2% female with a mean body mass index of 27.6 kg/m² and mean age of 55.2 years. Common comorbidities included hypertension (34.2%), depression (31.6%), and gastroesophageal reflux disease (28.9%). Hiatal/paraesophageal hernia repair (39.5%) or fundoplication (36.8%) preceded psGP diagnosis most often. The mean operative time was 30 ± 20 min. There were no intraoperative complications. Mean postoperative length of stay was 1.2 days. There were two readmissions within 30 days, one for melena and one for dehydration. The mean improvement in total Gastroparesis Symptom Index Score was 1.29 (p = 0.0002). The mean 4-h gastric retention improved from a pre-POP mean of 46.4 to 17.9% post-POP. Normal gastric emptying was noted in 50% of subjects with available follow-up imaging.

CONCLUSION

POP is a safe and effective endoscopic therapy for patients with psGP. POP should be considered a reasonable first-line option for patients with medically refractory psGP and may allow stomach preservation.

Pathophysiology of idiopathic gastroparesis and implications for therapy

OBJECTIVES

Idiopathic gastroparesis is a gastric motility disorder characterized by chronic upper gastrointestinal symptoms and delayed gastric emptying without an identifiable underlying condition. This review summarizes recent understanding of the pathophysiology and treatment of idiopathic gastroparesis.

MATERIALS AND METHODS

Structured literature search in the PubMed, Embase and ClinicalTrials.gov databases.

RESULTS

Idiopathic gastroparesis involves several alterations in gastric motility and sensation, including delayed gastric emptying, altered myoelectrical activity, impaired fundic accommodation, visceral hypersensitivity and disturbances in antropyloroduodenal motility and coordination. Multiple cellular changes have been identified, including depletion of interstitial cells of Cajal (ICC) and enteric nerves, as well as stromal fibrosis. The underlying cause of these changes is not fully understood but may be an immune imbalance, including loss of anti-inflammatory heme-oxygenase-1 positive (HO-1) macrophages. There is currently no causal therapy for idiopathic gastroparesis. The treatment ladder consists of dietary measures, prokinetic and antiemetic medications, and varying surgical or endoscopic interventions, including promising pyloric therapies. There are ongoing trials with several novel medications, raising hopes for future treatment.

CONCLUSIONS

Patients with idiopathic gastroparesis present several pathophysiological alterations in the stomach, where depletion of ICC is of special importance. Treatment is currently focused on alleviating symptoms through dietary adjustments, medication or surgical or endoscopic interventions.