Gastric per-oral endoscopic myotomy (G-POEM) for refractory gastroparesis: results from an international prospective trial

Gastric Per-Oral Endoscopy Myotomy (G-POEM): Tips, Tricks, and Pitfalls

PURPOSE OF REVIEW

The number of hospitalizations for gastroparesis has risen over 300% in recent decades with increased physical, psychological, and healthcare burdens. Gastric per-oral endoscopic myotomy (G-POEM) is a promising therapy for patients with refractory gastroparesis. This article reviews important considerations for G-POEM.

RECENT FINDINGS

Predictive factors for clinical success after G-POEM include diabetic and idiopathic gastroparesis, shorter gastroparesis duration, symptoms predominant of nausea and emesis, and gastric emptying study showing gastric retention of > 20% at 4 h. Mucosal closure is a critical step for G-POEM; both sutures and clips have high success rates, with clips having a trend to lower success rates but with significantly shorter procedure time and cheaper cost. G-POEMs have an overall 61% pooled success rate at one year with a yearly 13% symptom recurrence rate. A careful patient selection can yield higher clinical success rates. Further studies are needed on variant G-POEM techniques for more durable outcomes.

Current Concepts in Gastroparesis and Gastric Neuromuscular Disorders-Pathophysiology, Diagnosis, and Management

Upper gastrointestinal concerns including gastroparesis-like symptoms affect a large portion of the population, and determining the culprit condition can be difficult due to largely shared symptoms, clinical course, pathophysiology, and treatment pathways. The understanding of gastric neuromuscular disorders (GNDs) is emerging as a heterogeneous group encompassing conditions from gastroparesis to functional dyspepsia with chronic nausea, early satiety, bloating, or abdominal pain, irrespective of gastric emptying. This article aims to review the current concepts in gastroparesis and GNDs including pathophysiology, diagnosis, and management. While some established standards in their diagnosis and management exist, a number of novel diagnostics are becoming available. Durable therapeutic options are notably limited for such common conditions with chronic and debilitating symptoms, and neuromodulators may play a key role in symptom control, which has been previously under-recognized and underutilized. Advances in both pharmacologic treatment targets as well as noninvasive and invasive interventions and devices show promise in improving the experience of patients with gastroparesis-like symptoms. At this time, treatment of GNDs requires comprehensive multidisciplinary care from providers to achieve successful treatment outcomes.

Role of balloon dilation test in identifying suitable candidates for gastric peroral endoscopic myotomy

Background

Predicting successful outcomes of gastric peroral endoscopic myotomy (G-POEM) is essential for identifying patients who are most likely to benefit from the procedure. This study aimed to evaluate the utility of the balloon dilation test (BDT) in optimizing patient selection for G-POEM.

Methods

A retrospective study was conducted from February 2021 to December 2023, including patients with refractory gastroparesis unresponsive to conventional medical treatments. All patients completed the Gastroparesis Cardinal Symptom Index (GCSI) questionnaire before and after G-POEM. The pyloric ring balloon dilation test was performed prior to G-POEM, with only patients who showed a positive response included. Procedural and clinical outcomes were analyzed.

Results

Five patients (three female and two male) with refractory gastroparesis were included. The median G-POEM procedure time was 60 minutes (interquartile range [IQR] 32.5-110), and technical success was achieved in all cases. At a median follow-up of 10 months (IQR 6-34), clinical response was observed in all patients (100%). The GCSI score improved significantly from a median of 17 (IQR 8-33) to 0 (IQR 0-4.5; p < 0.03) indicating significant improvement in clinical symptoms.

Conclusion

A positive response to the balloon dilation test appears to be a reliable predictor of successful short-term outcomes following G-POEM in patients with refractory gastroparesis.

Long-term efficacy (at and beyond 1 year) of gastric peroral endoscopic myotomy for refractory gastroparesis: A systematic review and meta-analysis

INTRODUCTION

Although gastric peroral endoscopic myotomy (G-POEM) has shown substantial efficacy in patients with medically refractory gastroparesis (GP), comprehensive long-term data on its effectiveness are lacking.

METHODS

We conducted a systematic review and meta-analysis including observational studies assessing long-term efficacy after G-POEM in patients with refractory GP. Our primary outcome was the pooled rate of clinical success 1-year after G-POEM. Secondary outcomes included clinical success at 2 and 3 years and the rate of adverse events according to the American Society for Gastrointestinal Endoscopy classification.

RESULTS

Thirteen studies, involving 952 patients with refractory GP undergoing G-POEM, were eligible. The pooled 1 year-clinical success was 0.72 (95% confidence interval [CI]: 0.56, 0.85, I2 = 94.9%). The clinical success was 0.67 (95% CI: 0.47, 0.97, I2 = 95.8%) when considering only studies defining success as 1 point decrease in Gastroparesis Cardinal Symptoms Index score and at least 25% decrease in two subscales. For patients who had 1-year success, the pooled clinical success at 2 and 3 years were 0.71 (95% CI: 0.45, 0.92, I2 = 94.9%) and 0.58 (95% CI: 0.19, 0.92, I2 = 97.1%), respectively. The pooled rate of adverse events was 0.08 (95% CI: 0.06, 0.10, I2 = 0%).

CONCLUSION

G-POEM is associated with successful outcomes in about 70% of treated cases after 1 year, with durable long-term effects lasting up to 3 years. In the future, new uniform outcome definitions and strict patient selection criteria are warranted to delineate G-POEM outcomes more accurately.

Peroral endoscopic myotomy for achalasia and patients with normal lower-esophageal-sphincter integrated relaxation pressure: A propensity-score-matched retrospective study

BACKGROUND

Most patients who were included in previous studies on achalasia had increased lower esophageal sphincter (LES) pressure. Peroral endoscopic myotomy (POEM) has been confirmed to be effective at relieving the clinical symptoms of achalasia associated with increased LES pressure.

AIM

To identify the safety and efficacy of POEM for patients with normal LES integrated relaxation pressure (LES-IRP).

METHODS

The clinical data of patients who underwent POEM successfully in The First Medical Center of Chinese PLA General Hospital were retrospectively analyzed. A total of 481 patients who underwent preoperative high-resolution manometry (HRM) at our hospital were ultimately included in this research. According to the HRM results, the patients were divided into two groups: 71 patients were included in the normal LES-IRP group (LES-IRP < 15 mmHg) and 410 patients were included in the increased LES-IRP group (LES-IRP ≥ 15 mmHg). Clinical characteristics, procedure-related parameters, adverse events, and outcomes were compared between the two groups to evaluate the safety and efficacy of POEM for patients with normal LES-IRP.

RESULTS

Among the 481 patients included in our study, 209 were males and 272 were females, with a mean age of 44.2 years. All patients underwent POEM without severe adverse events. The median pre-treatment Eckardt scores of the normal LES-IRP and increased LES-IRP groups were 7.0 and 7.0 (P = 0.132), respectively, decreasing to 1.0 and 1.0 post-treatment (P = 0.572). The clinical success rate of the normal LES-IRP group was 87.3% (62/71), and that of the increased LES-IRP group was 91.2% (374/410) (P = 0.298). Reflux symptoms were measured by the GerdQ questionnaire, and the percentages of patients with GerdQ scores ≥ 9 in the normal LES-IRP and increased LES-IRP groups were 8.5% and 10.7%, respectively (P = 0.711). After matching, the rates of clinical success and the rates of GerdQ score ≥ 9 were not significantly different between the two groups.

CONCLUSION

Our results suggest that POEM is safe and effective for achalasia and patients with normal LES-IRP. In addition, in patients with normal LES-IRP, compared with those with increased LES-IRP, POEM was not associated with a greater incidence of reflux symptoms.

Electromechanical coupling across the gastroduodenal junction

The gastroduodenal junction is uniquely capable of regulating digestive functions in the gastrointestinal system. The pyloric sphincter, which demarcates the stomach from the small intestine, acts as a mechanical and electrical barrier, isolating each organ, thus enabling independent behaviors that are critical for proper digestion. Unique electrical patterns in the stomach, pylorus, and duodenum underpin the distinct contractile patterns of these regions, and improper organization of these mechanical behaviors leads to clinical conditions such as gastroparesis and dumping syndrome. For this reason, the gastroduodenal junction should be a focal point in investigations of novel biomarkers of gastrointestinal dysfunction. This review summarizes the current knowledge of bioelectrical and mechanical characteristics of the gastroduodenal junction, as well as the relevant underlying anatomy. As there is limited documentation of physiological recordings from the gastroduodenal junction of humans, inferences are made from animal studies and from measurements taken from other regions of the gastrointestinal tract, where appropriate. We suggest hypotheses on gastroduodenal electromechanical coupling and propose further studies to support or reject these ideas. Improved physiological understanding of this region, and the advent of novel diagnostic and therapeutic tools are crucial aspects for the future of clinical gastrointestinal medicine.

Functional constipation is associated with long-term clinical failure after gastric per-oral endoscopic myotomy for the treatment of gastroparesis

BACKGROUND

This study investigates the role of functional constipation (FC) in predicting the long-term success of Gastric Per-oral Endoscopic Myotomy (G-POEM) for treating gastroparesis.

METHODS

This was a retrospective observational study. Patients who underwent G-POEM between July 2015 and August 2022 with > 6-month follow-up were included. The primary objective was to evaluate the relationship between FC and G-POEM success. Secondary objectives included documenting the role of other digestive motility disorders, history of eating disorders, chronic opioid use, and cannabis use. Multivariate logistic regression analysis was used to evaluate the relationship between clinical success and various parameters, including FC.

RESULTS

80 patients were included, 58 women (72.5%) and 22 men (27.5%) with a mean age of 51.78 years. The mean follow-up was 3.4 years. Clinical success was observed in 52.5% of the patients' post-G-POEM. 42.5% had FC, 17.7% had esophageal motility disorders (EMD), and 13.9% had other motility disorders. In univariate analysis, FC and EMD were more frequent in patients with failure: 57.89 vs 28.57%, p = 0.015 and 28.95 vs 7.32%, p = 0.017, respectively. In multivariate analysis, the presence of FC (OR = 0.281 [0.105; 0.75], p = 0.0113) was the only predictive factor for success.

CONCLUSION

FC emerged as a significant predictor of lower clinical success rates after G-POEM. It suggests that an expanded gastrointestinal evaluation and treatment of other motility disorders may improve the outcomes for patients with gastroparesis treated with G-POEM.

Prognostic value of preoperative intragastric meal distribution in gastric emptying scintigraphy for long-term success of gastric peroral endoscopic myotomy in gastroparesis

BACKGROUND AND AIMS

Gastric emptying scintigraphy (GES) is the criterion standard for the diagnosis of gastroparesis. However, data are lacking regarding the prognostic value of preoperative intragastric meal distribution during GES in patients undergoing gastric peroral endoscopic myotomy (G-POEM) for gastroparesis. This study investigated the association of GES morphologic parameters and the long-term clinical success of G-POEM.

METHODS

This retrospective study included patients who underwent G-POEM for refractory gastroparesis in a tertiary center with preoperative GES data. Intragastric meal distribution was measured using the proximal to distal count ratio (PDCR) at 0, 1, 2 and 4 hours, and the retention index was calculated. Clinical success was defined as a decrease of at least 50% in the Gastroparesis Cardinal Symptom Index total score after G-POEM.

RESULTS

In total, 77 patients were included with a mean follow-up of 40.14 months. Clinical success was observed in 54.55% of patients. The retention index was not associated with clinical success. Only PDCR at 0 hours (PDCR0) was associated with clinical success. In univariate analysis, the median PDCR0 was 6.0 (interquartile range, 5.59) in patients with clinical success and 4.29 (interquartile range, 4.51) in patients with clinical failure (P = .019). In multivariate analysis, PDCR0 >5.25 was associated with clinical success (odds ratio, 4.36; 95% confidence interval, 1.55-12.26; P = .00524).

CONCLUSIONS

This study suggests that in patients with gastroparesis, a high PDCR0 value (suggestive for a preferential fundic meal distribution) during preoperative GES is associated with long-term clinical response to G-POEM.

Efficacy and safety of gastric peroral endoscopic myotomy across different etiologies of gastroparesis: systematic review and meta-analysis

BACKGROUND AND AIMS

Gastric peroral endoscopic myotomy (G-POEM) is an emerging treatment for refractory gastroparesis. Although its efficacy and safety have been analyzed in previous systematic reviews and meta-analyses, no studies have compared its effectiveness based on etiology. Our study aims to evaluate the efficacy and safety of G-POEM by etiologies of gastroparesis.

METHODS

We conducted a comprehensive search in major databases until October 2023, focusing on the efficacy and safety of G-POEM by etiology. Our primary outcome was clinical success based on etiology, with an additional subgroup analysis on Gastroparesis Cardinal Symptom Index (GCSI) scores before and after G-POEM based on etiology using standard meta-analysis methods and the random-effects model. Heterogeneity was assessed using I2 statistics.

RESULTS

In our analysis of 15 studies (7 retrospective, 8 prospective) involving 982 patients (mean patient age, 50.81 years; mean follow-up, 21 months), postsurgical conditions were the most common etiology in G-POEM (290 cases), followed by idiopathic factors (287 cases) and diabetes (286 cases). Subgroup analysis revealed pooled clinical success rates of 65% (95% confidence interval [CI], 51-77; I2 = 46%) for diabetes, 70% (95% CI, 46-86; I2 = 73%) for postsurgical conditions, and 60% (95% CI, 41-77; I2 = 68%) for idiopathic etiologies. Our research also indicated that G-POEM significantly improved GCSI scores: 1.7 (95% CI, -.01 to 3.5; P = .052) for diabetes, 1.34 (95% CI, -.07 to 2.62; P = .038) for postsurgical conditions, and 1.5 (95% CI, .36-2.75; P = .01) for idiopathic patients.

CONCLUSIONS

Based on this meta-analysis, G-POEM is effective and safe for treating refractory gastroparesis irrespective of the etiology, with significant improvements in clinical success rates and GCSI scores.

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 Outcomes After Gastric Peroral Endoscopic Myotomy for Refractory Gastroparesis: A Systematic Review

INTRODUCTION

Gastroparesis is a debilitating gastroduodenal disorder for which gastric peroral endoscopic myotomy (GPOEM) has emerged as an efficacious treatment option. However, response to GPOEM varies between 50% and 80%, such that preoperative predictors of treatment success are needed to guide patient selection.

METHODS

We performed a systematic review to identify predictors of clinical and functional response to GPOEM among adult patients with gastroparesis (PROSPERO: CRD42023457359). MEDLINE, Embase, and CENTRAL databases were searched systematically for studies reporting outcomes after GPOEM in September 2023. A narrative synthesis of predictive factors on univariable and multivariable analysis was performed with consideration of response rates through meta-analysis and evaluation of discrimination if prognostic models were developed. Risk Of Bias In Non-randomized Studies - of Exposures (ROBINS-E) was used for risk of bias assessment.

RESULTS

Of 1899 articles reviewed, 30 were included. The GPOEM response rate was 63.1% (95% confidence interval 56.3%-69.5%) with most studies defining clinical success on the basis of improvement in gastroparesis cardinal symptom index (87%, 26/30). Older age, shorter duration of gastroparesis, nondiabetic etiology, lower body mass index, and response to intrapyloric botulinum toxin were associated with positive response to GPOEM on multivariable analyses. Predictors on physiological tests such as EndoFLIP or gastric emptying scintigraphy were inconsistent. No prognostic models underwent external validation.

DISCUSSION

Currently, there are limited reproducible predictors of response to GPOEM among patients with refractory gastroparesis. Robust prospective studies investigating scalable, reproducible, and actionable biomarkers of treatment response are required.

Efficacy of gastric per-oral endoscopic myotomy remains similar after failure of interventional techniques in refractory gastroparesis

BACKGROUND AND AIMS

Gastric per-oral endoscopic myotomy (G-POEM) is a new therapeutic option for the treatment of refractory gastroparesis. However, the outcome of G-POEM after the failure of gastric electrical stimulation (GES) or other pylorus-targeting therapies has been poorly reported.

METHODS

Data were collected from patients referred for G-POEM for refractory gastroparesis. The efficacy in patients with previous interventional techniques was compared to patients naïve to instrumental technique. The primary endpoint was the 6-month clinical success rate, defined as at least a 1-point decrease in the Gastroparesis Cardinal Symptom Index (GCSI).

RESULTS

Among 48 patients referred for G-POEM, 32 patients had previous instrumental treatments (66%): 15 (31%) had GES, and 17 (35%) had pyloric endoscopic dilation or toxin injection. The technical success rate was 100%. At 6 months, clinical success was achieved in 25/48 patients (52%) and the GCSI decreased from 3.38 (2.94-3.95) to 2.25 (1.11-3.36) (p < 0.001). The 6-month success rate was similar in patients with or without previous instrumental treatment (50.0% vs 56.3%; p = 0.41). The complication rate was also similar in the two groups (6.3% vs 12.5%; p = 0.59), with only one severe adverse event. The only predictive factor for success at 6 months was a higher body mass index (OR = 1.14 [1.01-1.32]; p = 0.05).

CONCLUSION

G-POEM is safe and remains effective after GES or previous pyloric treatment failure, with 50% efficacy at 6 months. The therapeutic strategy in refractory gastroparesis remains to be defined.

Do antro-duodenal manometry parameters predict clinical response after gastric peroral endoscopic pyloromyotomy in refractory gastroparesis?

BACKGROUND

Gastric peroral endoscopic pyloromyotomy (G-POEM) is a promising therapeutic modality for refractory gastroparesis (GP). However, as characteristics of suitable patients for G-POEM remain unclear, antro-duodenal manometry (ADM) has been suggested to provide objective parameters for patient selection. The aim of the present study was to identify ADM parameters as predictors for treatment response after G-POEM in refractory GP.

METHODS

Refractory GP patients who underwent a G-POEM between 2017 and 2022 were included. The following ADM parameters were mainly scored: antral hypomotility, pylorospasm, and the presence of neuropathic enteric patterns. Treatment response was defined as a GCSI-score decrease of ≥1 point 12 months after G-POEM. Explorative analyses were performed on potential predictors of response using logistic regression analysis.

KEY RESULTS

Sixty patients (52 women, mean age 52 ± 14 years.) with refractory GP (33 idiopathic, 16 diabetic, 11 postsurgical) were included. Clinical response data were available for 52 patients. In 8 out of 60 patients, it was not feasible to advance the catheter beyond the pylorus. Abnormal ADM was found in 46/60 patients (77%). Antral hypomotility and pylorospasm were found in respectively 33% and 12% of patients. At least one neuropathic enteric dysmotility pattern was found in 58% of patients. No differences were found when comparing baseline ADM parameters between clinical response groups at 12 months follow-up. Following explorative analyses, no ADM parameters were identified to predict clinical response 12 months after G-POEM.

CONCLUSIONS AND INFERENCES

No ADM parameters were identified as predictors of clinical response after G-POEM in refractory GP patients. Additionally, a high percentage of abnormal ADM tracings was found, in particular with relation to enteric dysmotility, while only a low percentage of patients showed antral hypomotility or pylorospasm.

Gastric and sacral electrical stimulation for motility disorders-A clinical perspective

BACKGROUND

Electrical stimulation of the gut has been investigated in recent decades with a view to treating various gastro-intestinal motility disorders including, among others, gastric electrical stimulation to relieve nausea and vomiting associated with gastroparesis and sacral neuromodulation to treat fecal incontinence and/or constipation. Although their symptomatic efficacy has been ascertained by randomized controlled trials, their mechanisms of action are not fully understood.

PURPOSE

This review summarizes the past year's literature on the mechanisms of action of gut electrical stimulation therapies, including their impact on the gut-brain axis.

How to close mucosal incisions?

This article provides an overview of the techniques for closure of the mucosal entry point following advanced procedures in the third space. The outbreak of natural orifice transluminal endoscopic surgery (NOTES) has significantly impacted the treatment of various benign and malignant conditions. Reliable and secure closure of the mucosal entrance is essential for avoiding serious adverse events. Although small defects are typically closed using through-the-scope clips (TTSCs) or over-the-scope clips (OTSCs), challenges may occur with larger or transmural defects. Alternative methods, such as specialised stitches and full-thickness suturing systems, have been developed to address these challenges with promising results. Each method has its own pros and cons, and the choice of closure technique depends on various factors such as anatomical location, endoscopist expertise, costs, and clinical context. By understanding the technical specifications of each closure device, endoscopists can make decisions that enhance patient outcomes and minimise the risk of complications associated with the approximation of defect edges. Continued research is essential to optimise the evolution of newer closure devices and techniques for advancing NOTES.

Endoscopic pyloromyotomy for treatment of gastroparesis: A new standard or still an experimental approach?

Gastroparesis (GP) can be a severe and debilitating disease. Its pathophysiology is complex and not completely understood. Two principal mechanisms are responsible for the development of symptoms - gastric hypomotility and pylorospasm. Pylorus targeted therapies aim to decrease presumably elevated pyloric tone - pylorospasm. There is a growing body of evidence about their role in the treatment algorithm of GP. G-POEM (endoscopic pyloromyotomy) is an extensively studied pylorus targeted therapy. Its efficacy ranges between 56 and 80% and the number of recurrences among those with treatment effect seems low. G-POEM is a safe procedure with very low frequency of severe adverse events. At present, G-POEM should not be considered as an experimental approach and may be offered to all patients with refractory and severe GP. Nevertheless, G-POEM is not a first line treatment. Conservative measures such as diet modification and pharmacotherapy should always be tried before G-POEM is considered. Further research must focus on better patient selection as at present there are no standardized criteria. Functional imaging such as impedance planimetry (EndoFlip) may hold promise in this regard.

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.

Common Pathophysiological Mechanisms and Treatment of Diabetic Gastroparesis

Diabetic gastroparesis (DGP) is a common complication of diabetes mellitus, marked by gastrointestinal motility disorder, a delayed gastric emptying present in the absence of mechanical obstruction. Clinical manifestations include postprandial fullness and epigastric discomfort, bloating, nausea, and vomiting. DGP may significantly affect the quality of life and productivity of patients. Research on the relationship between gastrointestinal dynamics and DGP has received much attention because of the increasing prevalence of DGP. Gastrointestinal motility disorders are closely related to a variety of factors including the absence and destruction of interstitial cells of Cajal, abnormalities in the neuro-endocrine system and hormone levels. Therefore, this study will review recent literature on the mechanisms of DGP and gastrointestinal motility disorders as well as the development of prokinetic treatment of gastrointestinal motility disorders in order to give future research directions and identify treatment strategies for DGP.

Prevalence and disease burden of gastroparesis in Asia

Gastroparesis is a gastrointestinal disorder characterized by significant prolongation of gastric emptying time caused by impaired motility of the stomach. Its estimated prevalence is 24.2 per 100 000 people. However, the prevalence of gastroparesis in Asian countries is unknown due to a limited number of epidemiological studies and significant phenotypic variability of the Asian population in these studies. Analysis of previous research on gastroparesis and functional bowel disorders reveals the possibility of an increased prevalence among Asian individuals. A comparison of ethnic constituents between the recent United Kingdom gastroparesis study and its mother database has demonstrated a higher prevalence of gastroparesis among British Asian patients when compared with British Caucasian patients. An estimated gastroparesis prevalence in the Asian population can be calculated by identifying the individuals who are likely to demonstrate a delayed gastric emptying from all diagnosed functional dyspepsia patients. We suggest that gastroparesis tends to be underdiagnosed in Asians due to a lack of studies on gastroparesis in the Asian continent, a lack of knowledge among practitioners, and poor availability of scintigraphy testing as well as limited therapeutic options for this disease. Given the high probability of Asian predominance in gastroparesis and its disease impact on quality of life, epidemiological research focusing on the Asian population is required.

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.

Characterization of gastric dysfunction after fundoplication using body surface gastric mapping

BACKGROUND

Adverse gastric symptoms persist in up to 20% of fundoplication operations completed for gastroesophageal reflux disease, causing significant morbidity and driving the need for revisional procedures. Noninvasive techniques to assess the mechanisms of persistent postoperative symptoms are lacking. This study aimed to investigate gastric myoelectrical abnormalities and symptoms in patients after fundoplication using a novel noninvasive body surface gastric mapping (BSGM) device.

METHODS

Patients with a previous fundoplication operation and ongoing significant gastroduodenal symptoms and matched controls were included. BSGM using Gastric Alimetry (Alimetry Ltd) was employed, consisting of a high-resolution 64-channel array, validated symptom-logging application, and wearable reader.

RESULTS

A total of 16 patients with significant chronic symptoms after fundoplication were recruited, with 16 matched controls. Overall, 6 of 16 patients (37.5%) showed significant spectral abnormalities defined by unstable gastric myoelectrical activity (n = 2), abnormally high gastric frequencies (n = 3), or high gastric amplitudes (n = 1). Patients with spectral abnormalities had higher Patient Assessment of Upper Gastrointestinal Disorders-Symptom Severity Index scores than those of patients without spectral abnormalities (3.2 [range, 2.8-3.6] vs 2.3 [range, 2.2-2.8], respectively; P = .024). Moreover, 7 of 16 patients (43.8%) had BSGM test results suggestive of gut-brain axis contributions and without myoelectrical dysfunction. Increasing Principal Gastric Frequency Deviation and decreasing Rhythm Index scores were associated with symptom severity (r > .40; P < .05).

CONCLUSION

A significant number of patients with persistent postfundoplication symptoms displayed abnormal gastric function on BSGM testing, which correlated with symptom severity. Our findings advance the pathophysiologic understanding of postfundoplication disorders, which may inform diagnosis and patient selection for medical therapy and revisional procedures.

Gastric volumetry for the assessment of fundic compliance and visceral hypersensitivity in patients with gastroparesis: a retrospective comparative study

BACKGROUND/AIMS

The evaluation of visceral hypersensitivity and gastric accommodation in patients with gastroparesis (GP) is difficult. CT-scan gastric volumetry allows to test the distension of different regions of the stomach. We aimed to study gastric volumes and patient's sensitivity to gastric distension between in patients with GP compared to patients with GERD.

METHOD

Retrospective study including patients who had CT-scan volumetry for GP or GERD. Two CT-scan series were made after gastric distension: left lateral decubitus 30° (LLD30) for antrum and right lateral decubitus (RLD) for body. Pain and discomfort were assessed using visual analogue scale (VAS). Gastric volumes were measured for LLD30 and RLD.

RESULTS

13 patients (7 GP and 6 GERD) were included. Mean age was 35.6+/-7.3 years. Median gastric volume in the RLD was lower in GP vs GERD (927+/-208 ml vs. 1115+/-163 ml; p = 0.046) while it was similar for LLD30 (1053+/-228 ml vs. 1054+/-193 ml; p = 0.603). GP patients had significantly more pain and discomfort during the procedure: pain VAS for GP was 6[0-9] versus 0[0-2] for GERD, p = 0.004, discomfort VAS for GP was 7[4-10] versus 4[0-5] for GERD, p = 0.007. 66.7% of GERD patients felt no pain vs. 14.3% in GP, p = 0.053.

CONCLUSION

This pilot study suggests that GP could be associated with a reduced gastric volume compared to GERD in RLD after gaseous distension. In contrast, patient self-assessment of pain related to gastric distension was greater int GP patients. A lack of fundus accommodation and visceral hypersensitivity could explain some mechanisms in the genesis of GP symptoms.

Management of Gastrointestinal Symptoms in Parkinson's Disease: A Comprehensive Review of Clinical Presentation, Workup, and Treatment

Gastrointestinal symptoms in Parkinson's disease (PD) are among the most prevalent and debilitating of complications and present unique diagnostic and management challenges. Patients with PD commonly experience dysphagia, nausea, bloating, and constipation related to pathologic involvement of the enteric nervous system. In turn, gastrointestinal complications may impact motor fluctuations and the efficacy of levodopa therapy. This review will explore the common gastrointestinal manifestations of PD with an emphasis on clinical presentation, workup, and treatment strategies.

Role of gastric peroral endoscopic myotomy (GPOEM) in chronic gastroparesis management after pancreas transplantation

Gastroparesis is a common complaint among patients with diabetes. Symptoms tend to improve following successful pancreas transplantation (PTx), but persist despite euglycemia in a subset of patients. We aimed to assess the benefit of gastric peroral endoscopic myotomy (G-POEM) in persistent gastroparesis following PTx. This was a single center retrospective review of all patients who underwent G-POEM for persistent gastroparesis following PTx. Patient demographics, pre and post procedure perception of symptom severity according to the patient assessment of upper gastrointestinal symptoms severity index (PAGI-SYM), gastroparesis cardinal symptom index (GCSI) score, and 36-item short form survey (SF36) score along with gastric emptying scintigraphy (GES) were analyzed. Seven PTx recipients underwent G-POEM for persistent gastroparesis symptoms. The majority were female. All reported nausea/vomiting, abdominal pain, bloating, and post prandial fullness prior to G-POEM. The post procedure survey scores improved in all patients although this was not significant. The improvement in gastric emptying on GES was statistically significant. G-POEM is a relatively new treatment option for gastroparesis. While it requires specialized proceduralist and training, we have documented improvement in the management of symptoms. With increasing experience, we anticipate more significant benefit in post PTx patients with persistent symptoms of gastroparesis undergoing G-POEM.

Recent advances in the treatment of gastrointestinal motility disorders in children

INTRODUCTION

Pediatric gastrointestinal motility disorders represent some of the most challenging clinical conditions with largely undefined pathogenetic pathways and therefore limited therapeutic options. Herein, we provide an overview of the recent advances in treatment options for these disorders and their clinical impact.

AREAS COVERED

PubMed and Medline databases were searched for relevant articles related to the treatment of achalasia, esophageal atresia, gastroparesis, PIPO and constipation published between 2017 and 2022. In this article, we review and summarize recent advances in management of gastrointestinal motility disorders in children with a particular focus on emerging therapies as well as novel diagnostic modalities that help guide their application or develop new, more targeted treatments.

EXPERT OPINION

Gastrointestinal motility disorders represent one of the most challenging conundrums in pediatric age and despite significant advances in investigative tools, the palette of treatment options remain limited. Overall, while pharmacological options have failed to bring a curative solution, recent advances in minimal invasive therapeutic and diagnostic techniques have emerged as potential keys to symptom and quality of life improvement, such as ENDOFLIP, POEM, cine-MRI, fecal microbiota transplantation.

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.

Gastric peroral endoscopic myotomy for management of refractory gastroparesis in patients with gastric neurostimulator devices: a multicenter retrospective case control study

BACKGROUND AND AIMS

Gastric neurostimulation (GNS) and gastric peroral myotomy (G-POEM), therapies for refractory gastroparesis, are associated with suboptimal outcomes. We studied the role of G-POEM as a salvage therapy in patients with refractory symptoms after GNS implantation.

METHODS

This was a multicenter, retrospective, matched case-control study. Consecutive patients with a GNS device and who underwent G-POEM as a salvage therapy for clinical failure (cases) and patients without GNS implantation and who underwent G-POEM for refractory gastroparesis (control) between October 2018 and August 2021 were included. The primary outcome was clinical success after G-POEM.

RESULTS

A total of 123 patients (mean age 45.7 ± 14.7 years; 88 female subjects [72%]) underwent G-POEM therapy during the study: 41 cases and 82 controls. Clinical success was achieved in 66% in the case group and 65% in the control group (P = .311), during a median total clinical follow-up time of 11.8 (interquartile range, 2.4-6.3) months. In the case group, the mean Gastroparesis Cardinal Symptom Index score decreased from 2.8 ± 1.8 to 1.5 ± 1.9 (P = .024), and gastric retention at 4 hours improved from 45% ± 25.8% to 16.6% ± 13.1% (P = .06). The mean delta improvement in the subscales of nausea/vomiting (1.3 ± .6 vs .9 ± 1.1, P = .044) and bloating (1.6 ± 1.3 vs 1.2 ± 1.4, P = .041) were significantly higher in cases than in controls.

CONCLUSIONS

Among patients with refractory symptoms after GNS, G-POEM can be a reasonable salvage therapy to provide further symptomatic relief with evidence of a potential additive effect of both G-POEM and GNS.

Imaging in Gastroparesis: Exploring Innovative Diagnostic Approaches, Symptoms, and Treatment

Gastroparesis (GP) is a chronic disease characterized by upper gastrointestinal symptoms, primarily nausea and vomiting, and delayed gastric emptying (GE), in the absence of mechanical GI obstruction. The underlying pathophysiology of GP remains unclear, but factors contributing to the condition include vagal nerve dysfunction, impaired gastric fundic accommodation, antral hypomotility, gastric dysrhythmias, and pyloric dysfunction. Currently, gastric emptying scintigraphy (GES) is considered the gold standard for GP diagnosis. However, the overall delay in GE weakly correlates with GP symptoms and their severity. Recent research efforts have focused on developing treatments that address the presumed underlying pathophysiological mechanisms of GP, such as pyloric hypertonicity, with Gastric Peroral Endoscopic Myotomy (G-POEM) one of these procedures. New promising diagnostic tools for gastroparesis include wireless motility capsule (WMC), the 13 carbon-GE breath test, high-resolution electrogastrography, and the Endoluminal Functional Lumen Imaging Probe (EndoFLIP). Some of these tools assess alterations beyond GE, such as muscular electrical activity and pyloric tone. These modalities have the potential to characterize the pathophysiology of gastroparesis, identifying patients who may benefit from targeted therapies. The aim of this review is to provide an overview of the current knowledge on diagnostic pathways in GP, with a focus on the association between diagnosis, symptoms, and treatment.

Gastroparesis: Myths, Misconceptions, and Management

Gastroparesis (GP), a historically vexing disorder characterized by symptoms of nausea, vomiting, abdominal pain, early satiety, and/or bloating, in the setting of an objective delay in gastric emptying, is often difficult to treat and carries a tremendous burden on the quality of patients' lives, as well as the healthcare system in general. Though the etiology of GP has been fairly well defined, much work has been done recently to better understand the pathophysiology of GP, as well as to identify novel effective and safe treatment options. As our understanding of GP has evolved, many myths and misconceptions still abound in this rapidly changing field. The goal of this review is to identify myths and misconceptions regarding the etiology, pathophysiology, diagnosis, and treatment of GP, in the context of the latest research findings which have shaped our current understanding of GP. Recognition and dispelling of such myths and misconceptions is critical to moving the field forward and ultimately advancing the clinical management of what will hopefully become a better understood and more manageable disorder in the future.

Response to botulinum toxin may predict response to peroral pyloromyotomy in patients with gastroparesis

BACKGROUND : Patients with gastroparesis who have undergone prior intrapyloric botulinum toxin injection (BTI) may seek an opinion regarding peroral pyloromyotomy (POP). There are only two small reports assessing the role of BTI as a predictor for successful treatment with POP.

METHODS

We performed a retrospective cohort study to assess whether symptomatic improvement after BTI predicts a response to POP. We included 119 patients who had undergone both BTI and POP at Cleveland Clinic Ohio or Cleveland Clinic Florida from January 2016 to September 2019.

RESULTS

65.5 % of patients had symptomatic improvement after BTI. Gastroparesis Cardinal Symptom Index (GCSI) scores were available for 74 patients, with 64 % achieving a response to POP, defined as a decrease in mean GCSI ≥ 1. In multivariable analysis, response to BTI (odds ratio [OR] 7.7 [95 %CI 2.2-26.1]) and higher pre-POP GCSI score (OR 2.3 [95 %CI 1.2-4.6]) were independent predictors of response to POP.

CONCLUSIONS

Clinical improvement after BTI is a predictor of response to POP in patients with gastroparesis. This information may aid in improving patient selection for POP.

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.

The Role of Microbiota in Upper and Lower Gastrointestinal Functional Disorders

Functional gastrointestinal disorders (FGIDs), also known as disorders of gut-brain interaction, are a group of disorders characterized by chronic gastrointestinal symptoms in the absence of demonstrable pathology on conventional testing [...].

Gastric Peroral Endoscopic Pyloromyotomy for Infants With Congenital Hypertrophic Pyloric Stenosis

INTRODUCTION

Congenital hypertrophic pyloric stenosis (CHPS), the most common infantile disease requiring surgical intervention, is routinely treated with open or laparoscopic pyloromyotomy. Recently, gastric peroral endoscopic pyloromyotomy (G-POEM) has been used for adult gastroparesis. We aimed to evaluate the efficacy and safety of G-POEM in treating infantile CHPS.

METHODS

We reviewed data from 21 G-POEM-treated patients at 3 tertiary children's endoscopic centers in China between January 2019 and December 2020. Clinical characteristics, procedure-related parameters, perioperative management, and follow-up outcomes were summarized.

RESULTS

G-POEM was performed successfully in all patients. The median operative duration was 49 (14-150) minutes. The submucosal tunnels were successfully established along the greater curvature of the stomach in 19 cases, and 2 cases were switched to the lesser curvature because of difficulty. No perioperative major adverse events occurred. Minor adverse events included inconsequential mucosal injury in 5 cases and unsatisfactory closure of the mucosal incision in 1 case. Upper gastrointestinal contrast radiography in all patients showed smooth passage of the contrast agent through the pylorus on postoperative day 3. The growth curves of the patients reached normal levels 3 months after the procedure. No recurrent clinical symptoms occurred in any patient during the median follow-up period of 25.5 (14-36) months.

DISCUSSION

G-POEM is feasible, safe, and effective for infants with CHPS, with satisfactory clinical responses over a short-term follow-up. Further multicenter studies should be performed to compare the long-term outcomes of this minimally invasive technique with open or laparoscopic pyloromyotomy.

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.

Endoscopic findings do not predict per-oral pyloromyotomy (POP) response

INTRODUCTION

Gastroparesis is a life-altering diagnosis caused by the stomach's inability to function in the absence of a mechanical obstruction. The primary causes are idiopathic, diabetic, and postoperative. Our first-line treatment for medical refractory gastroparesis is the endoscopic per-oral pyloromyotomy (POP) procedure. Predicting clinical response cost effectively remains elusive.

METHODS

All patients who underwent a POP procedure at our institution by a single surgical endoscopist from January 1, 2019 to June 30, 2020 were retrospectively reviewed. All endoscopic data were prospectively collected. The patients were followed by a survey including the Gastroparesis Cardinal Symptom Index (GCSI) and other relevant postoperative measures. The primary endpoint was clinical response defined as ≥ 1.0 decrease in the GCSI from preoperative to the time of survey. Secondary outcome was normalization of the gastric emptying study (GES).

RESULTS

Our patient population is 85% female and has an average age of 44.8 years. The diagnosis of gastroparesis is 71% iatrogenic, 19% postoperative, and 10% diabetic. On endoscopy, 30% had bile in the stomach and 65% had any degree of pylorospasm. The primary outcome measure of clinical response was 39% at an average of 697 ± 151 days post-POP, but 66% of patients attested to an improvement in their symptoms. Of 68 postoperative gastric emptying studies 50% normalized at an average of 145 ± 98 days. Following univariate and multivariate analyses of preoperative data and endoscopic findings, there were no significant predictors of clinical response. A preoperative GCSI ≥ 2.6 trends toward significance (OR 6.87, p = 0.058).

CONCLUSION

Endoscopic findings at the time of POP do not correlate with clinical response. The GCSI model currently used to measure clinical response may not accurately capture the full clinical picture. The long-term durability of endoscopic myotomy to treat medical refractory gastroparesis needs to be studied further to improve patient selection.

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.

Gastroparesis and Functional Dyspepsia: Spectrum of Gastroduodenal Neuromuscular Disorders or Unique Entities?

Gastroparesis is defined by delayed gastric emptying in the absence of mechanical obstruction of the stomach. Patients experience symptoms of nausea, vomiting, abdominal pain, fullness, and early satiety. The recognition of the disorder has progressed due to availability of gastric emptying scintigraphy and advancements made in understanding its pathophysiology and treatment options. The clinical presentation and treatment of gastroparesis overlap with a more commonly recognized disorder of gut-brain interaction, functional dyspepsia. Recent studies have reenergized the discussion whether these two are separate entities or perhaps reflect a spectrum of gastroduodenal neuromuscular disorders. The societal guidelines conflict on the utility of gastric emptying scintigraphy in assessment of patients with upper gastrointestinal symptoms. A better appraisal of similarities and differences between gastroparesis and functional dyspepsia will allow targeted treatment for these disorders. This is particularly important as specific pharmacological and endoscopic treatment options are being developed for gastroparesis which are unlikely to be helpful for functional dyspepsia. This review makes the case for considering these disorders in a spectrum where identification of both would most ideally position us toward providing the optimal clinical care.

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

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

Evolving field of third-space endoscopy: Derivatives of peroral endoscopic myotomy

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

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.

GIE Editorial Board Top 10: advances in GI endoscopy in 2021

The 9-member Editorial Board of the American Society for Gastrointestinal Endoscopy performed a systematic literature search of original articles published during 2021 in Gastrointestinal Endoscopy and 10 other high-impact medical and gastroenterology journals on endoscopy-related topics. Votes from each editorial board member were tallied to identify a consensus list of the 10 most significant topic areas in GI endoscopy over the calendar year of study, with a focus on 3 criteria: significance, novelty, and global impact on clinical practice. The 10 areas identified collectively represent advances in the following endoscopic topics: colonoscopy optimization, bariatric endoscopy, endoscopic needle sampling and drainage, peroral endoscopic myotomy, endoscopic defect closure, meeting systemic challenges in endoscopic training and practice, endohepatology, FNA versus fine-needle biopsy sampling, endoscopic mucosal and submucosal procedures, and cold snare polypectomy. Each board member contributed a summary of important articles relevant to 1 to 2 of the consensus topic areas, leading to a collective summary that is presented in this document of the "top 10" endoscopic advances of 2021.

Normal and disordered gastric emptying in diabetes: recent insights into (patho)physiology, management and impact on glycaemic control

Gastric emptying is a major determinant of postprandial blood glucose, accounting for ~35% of variance in peak glucose in both healthy individuals and those with type 2 diabetes. Gastric emptying is frequently disordered in individuals with diabetes (both abnormally delayed and accelerated). Delayed gastric emptying, i.e. diabetic gastroparesis, may be linked to upper gastrointestinal symptoms for which current treatment remains suboptimal; pharmacological acceleration of delayed emptying is only weakly associated with symptom improvement. Accordingly, the relationship between symptoms and delayed gastric emptying is not simply 'cause and effect'. In insulin-treated patients, disordered gastric emptying, even when not associated with gastrointestinal symptoms, can cause a mismatch between the onset of insulin action and the availability of absorbed carbohydrate, leading to suboptimal glycaemic control. In patients with type 2 diabetes, interventions that slow gastric emptying, e.g. glucagon-like peptide-1 receptor agonists, reduce postprandial blood glucose. This review focuses on recent insights into the impact of gastric emptying on postprandial blood glucose, effects of diabetes therapy on gastric emptying and the management of disordered gastric emptying in diabetes. In view of the broad relevance of gastric emptying to diabetes management, it is important that future clinical trials evaluating novel therapies that may affect gastric emptying should quantify the latter with an appropriate technique, such as scintigraphy or a stable isotope breath test.

Gastric sensorimotor function and its clinical measurement

BACKGROUND

Gastroduodenal symptoms are highly prevalent, with underlying sensorimotor dysfunction contributing in many patients. Common symptoms include early satiation, postprandial fullness, epigastric bloating, pain or burning, nausea and vomiting, which collectively affect over 7% of adults. However, the clinical evaluation of these symptoms remains challenging, with current tests of gastric function remaining limited in their ability or availability to separate specific patient subgroups or guide-targeted care.

PURPOSE

In the current edition of Neurogastroenterology & Motility, Silver et al. present new data showing correlations between patterns of intragastric meal distribution and symptom profiles in a large series of patients undergoing gastric emptying scintigraphy. Studies of this type are important, as they motivate understanding beyond existing disease labels, and orient focus toward deeper mechanistic profiling. This brief review provides an overview of gastric sensorimotor function and profiles several current and emerging methods of clinical evaluation. Perspectives are provided on accommodation testing, gastric emptying, measuring gastric myoelectrical activity including new approaches, and antroduodenal manometry. Although gastric physiology is complex, recent progress has been encouraging, with the heterogenous pathophysiology of gastric symptoms continuing to be unraveled, and new techniques for evaluating gastric function and symptoms emerging.

CONCLUSIONS AND INFERENCES

Ongoing progress will now depend on continuing to accurately profile the underlying mechanisms of gastroduodenal disorders to identify specific disease phenotypes that inform care.

A New Paradigm Shift in Gastroparesis Management

Gastroparesis, once regarded as a rare disease, is difficult to diagnose and challenging to treat; there were many breakthrough advances in the 2010s, shifting the paradigm of the understanding of this complex entity and its management. Similar to diabetes, its increasing prevalence reflects increased accessibility to diagnostic modalities and suggests that gastroparesis was underacknowledged in the past. Major developments in the three main aspects of the disease include the discovery of smooth muscle cells, interstitial cells of Cajal, PDGFRα+ cells syncytium, rather than interstitial cells of Cajal alone, as the main gastric pacemaker unit; the development of validated point-of-care diagnostic modalities such as a wireless motility capsule, the carbon 13-labeled breath test, and impedance planimetry; and the introduction of novel minimally invasive therapeutic options such as newer pharmacologic agents and gastric peroral endoscopic pyloromyotomy. All aspects of these advances will be discussed further in this review.