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

Quantification of interstitial cells of Cajal and fibrosis during gastric per-oral endoscopic myotomy and its association with clinical outcomes

Background and study aims Alterations to interstitial cells of Cajal (ICC) and collagen fibrosis have been implicated in the pathogenesis of gastroparesis. We aimed to evaluate the feasibility and safety of pyloric muscle sampling during gastric peroral endoscopic myotomy (G-POEM) and the association between pyloric ICC density and degree of fibrosis with clinical outcomes. Patients and methods This was a single-center prospective study of gastroparetic patients who underwent G-POEM and intraprocedural pyloric muscle biopsies between January 2022 and April 2023. ICC count was estimated using CD117 stain and trichome for collagen fibrosis. Clinical response to G-POEM was defined as an improvement of ≥ 1 point on the Gastroparesis Cardinal Symptom Index. Results Fifty-six patients (median age 60 years, 71.4% women) underwent G-POEM (100% technical success; 71.4% clinical response). ICC depletion (< 10/high-power field) and fibrosis were encountered in 70.4% and 75% of the cases, respectively. There was no difference in mean ICC count between G-POEM responders vs. non-responders (7±3.6 vs. 7.7±3.3; P = 0.9). There was no association between ICC density or degree of fibrosis with the etiology of gastroparesis, duration of symptoms, gastric emptying rate, or pyloric impedance planimetry. Patients who did not respond to G-POEM had a significantly higher degree of moderate/severe fibrosis when compared with those who responded (81.3% vs. 25%; P = 0.0002). Conclusions Pyloric muscle biopsies during G-POEM was feasible and safe. ICC depletion and pyloric muscle fibrosis are common in gastroparetic patients. The degree of fibrosis may be related to pyloric dysfunction and clinical response to G-POEM. Additional studies are needed to confirm these results.

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

INTRODUCTION

Gastric Per-Oral Endoscopic Myotomy (GPOEM) has been developed as an effective treatment option for patients with medically refractory gastroparesis. Other endoscopic options, such as pyloric injection of botulinum toxin (Botox), is often performed with limited efficacy. The purpose of this study was to evaluate GPOEM for the treatment of gastroparesis and compare its efficacy to Botox injection results reported in the literature.

METHODS

A retrospective review was conducted to identify all patients who underwent a GPOEM for the treatment of gastroparesis between September 2018 and June 2022. Changes in Gastric Emptying Scintigraphy (GES) studies and Gastroparesis Cardinal Symptom (GCSI) scores from the preoperative to postoperative period were analyzed. In addition, a systematic review was conducted to identify all publications reporting the outcomes of Botox injections for the treatment of gastroparesis.

RESULTS

A total of 65 patients (51 female, 14 male) underwent a GPOEM during the study period. Twenty-eight patients (22 female, 6 male) had both preoperative and postoperative GES studies in addition to GCSI scores. The etiologies of gastroparesis were diabetic (n = 4), idiopathic (n = 18), and postsurgical (n = 6). Fifty percent of these patients had undergone previous failed interventions including Botox injections (n = 6), gastric stimulator placement (n = 2), and endoscopic pyloric dilation (n = 6). Outcomes showed a significant decrease in GES percentages (mean difference = - 23.5%, p < 0.001) and GCSI scores (mean difference = - 9.6, p = 0.02) postoperatively. In the systematic review for Botox, transient mean improvements in postoperative GES percentages and GCSI scores were reported at 10.1% and 4.0, respectively.

CONCLUSION

GPOEM leads to significant improvement in GES percentages and GCSI scores postoperatively and is superior to Botox injection results reported in the literature.

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.

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.

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.

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

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

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

BACKGROUND AND AIMS

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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 per-oral endoscopic myotomy: Indications, technique, results and comparison with surgical approach

Gastroparesis is a chronic disease of the stomach that causes a delayed gastric emptying, without the presence of a stenosis. For 30 years the authors identified pylorospasm as one of the most important pathophysiological mechanisms determining gastroparesis. Studies with EndoFLIP, a device that assesses pyloric distensibility, increased the knowledge about pylorospasm. Based on this data, several pyloric-targeted therapies were developed to treat refractory gastroparesis: Surgical pyloroplasty and endoscopic approach, such as pyloric injection of botulinum and pyloric stenting. Notwithstanding, the success of most of these techniques is still not complete. In 2013, the first human gastric per-oral endoscopic myotomy (GPOEM) was performed. It was inspired by the POEM technique, with a similar dissection method, that allows pyloromyotomy. Therapeutical results of GPOEM are similar to surgical approach in term of clinical success, adverse events and post-surgical pain. In the last 8 years GPOEM has gained the attention of the scientific community, as a minimally invasive technique with high rate of clinical success, quickly prevailing as a promising therapy for gastroparesis. Not surprisingly, in referral centers, its technical success rate is 100%. One of the main goals of recent studies is to identify those patients that will respond better to the therapies targeted on pylorus and to choose the better approach for each patient.

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

BACKGROUND

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

AIM

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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

Background and Aims

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

Methods

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

Results

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

Conclusions

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

Short-term outcomes of different modalities of pyloromyotomy versus gastric electrical stimulation in the treatment of gastroparesis: A systemic review and meta-analysis

BACKGROUND

The aim of this meta-analysis was to compare the short-term outcomes surrounding the efficacy and complication rate between different modalities of pyloromyotomy and gastric electrical stimulation (GES) in the treatment of gastroparesis.

METHODS

Comprehensive, computerized research was performed on PubMed, Embase, and the Cochrane Central Register of Controlled Trials. We additionally reviewed relevant articles, without any language limitations, published prior to April 15, 2020. Meta-analysis was conducted using RevMan 5.3 software.

RESULTS

Three studies totaling 196 participants who had received 4 interventions, including single per-oral pyloromyotomy (POP), double POP, laparoscopic pyloromyotomy, and GES, were eligible for analysis. Compared to single POP, double POP achieved a better clinical response with a pooled relative risk (RR) of 1.27 (95% confidence interval [CI], 1.01-1.60, P = .04), while laparoscopic pyloromyotomy and GES showed no difference with a pooled RR of 0.89 (95% CI, 0.74-1.08, P = .23) and 0.87 (95% CI, 0.73-1.04, P = .13), respectively. As for the recurrence and complication rates, only GES showed a borderline significance of recurrence in comparison to single POP (RR 2.17, 95% CI, 1.00-4.71, P = .05), while there were no differences in the remainder of the comparisons.

CONCLUSIONS

We conducted a detailed comparison of 3 modalities of pyloromyotomy and GES in the treatment of gastroparesis, with the results suggesting that double POP demonstrated better clinical success with similar recurrence and complication rates. In addition, GES may result in more recurrence amongst these interventions.

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.

Direct optogenetic stimulation of smooth muscle cells to control gastric contractility

Rationale: Antral peristalsis is responsible for gastric emptying. Its failure is called gastroparesis and often caused by dysfunction of enteric neurons and interstitial cells of Cajal (ICC). Current treatment options, including gastric electrical stimulation, are non-satisfying and may improve symptoms but commonly fail to restore gastric emptying. Herein, we explore direct optogenetic stimulation of smooth muscle cells (SMC) via the light-gated non-selective cation channel Channelrhodopsin2 (ChR2) to control gastric motor function.

Methods: We used a transgenic mouse model expressing ChR2 in fusion with eYFP under the control of the chicken-β-actin promoter. We performed patch clamp experiments to quantify light-induced currents in isolated SMC, Ca²⁺ imaging and isometric force measurements of antral smooth muscle strips as well as pressure recordings of intact stomachs to evaluate contractile responses. Light-induced propulsion of gastric contents from the isolated stomach preparation was quantified in video recordings. We furthermore tested optogenetic stimulation in a gastroparesis model induced by neuronal- and ICC-specific damage through methylene blue photo-toxicity.

Results: In the stomachs, eYFP signals were restricted to SMC in which blue light (460 nm) induced inward currents typical for ChR2. These depolarizing currents led to contractions in antral smooth muscle strips that were stronger than those triggered by supramaximal electrical field stimulation and comparable to those evoked by global depolarization with high K⁺ concentration. In the intact stomach, panoramic illumination efficiently increased intragastric pressure achieving 239±46% (n=6) of the pressure induced by electrical field stimulation and triggered gastric transport. Within the gastroparesis model, electric field stimulation completely failed but light still efficiently generated pressure waves.

Conclusions: We demonstrate direct optogenetic stimulation of SMC to control gastric contractility. This completely new approach could allow for the restoration of motility in gastroparesis in the future.

Per-oral Endoscopic Myotomy and Other Applications of Third Space Endoscopy: Current Status and Future Perspectives

INTRODUCTION

The modification of NOTES (natural orifice transluminal endoscopic surgery) by mucosal safety flap has introduced us to the world of third space endoscopy (TSE). POEM (per-oral endoscopic myotomy) for achalasia cardia being its first vista, the realm expanded so that we can now remove en bloc a subepithelial/intramural tumor by POET (per-oral endoscopic tumor resection), perform G-POEM (gastric per-oral endoscopic myotomy) for refractory gastroparesis, restore esophageal continuity in complete obstruction by performing POETRE (per-oral endoscopic tunneling for the restoration of the esophagus), divide the septum in Zenker diverticulum completely with negligible risk of perforation by Z-POEM (Zenker per-oral endoscopic myotomy) and relieve constipation in Hirschsprung disease by PREM (per-rectal endoscopic myotomy). However, the real potential of TSE became evident with the introduction of POEM with fundoplication. TSE has opened the gates of the peritoneal cavity. Improved expertise and equipment will make the role of endoscopist complimentary to the surgeon with the dawn of a new field in therapeutic endoscopy.

AREAS COVERED

This review intends to comprehensively discuss the various aspects of POEM for achalasia studied so far followed by a brief discussion about other applications of TSE and the future perspectives in this exciting field.

Gastric Per-Oral Endoscopic Myotomy for Treatment of Chronic Proximal Staple Line Leak Precipitated by Downstream Stenosis

Laparoscopic sleeve gastrectomy is now the most commonly performed bariatric surgery. Although considered a safe procedure, adverse events such as staple line leak in the context of sleeve stenosis can result in significant patient morbidity and health economic burden. Correction of the downstream stenosis is mandatory for closure of the staple line leak. Conventional endoscopic therapies offer high initial success rates, though ultimately a significant proportion proceed to revision surgery. Gastric per-oral endoscopic myotomy (G-POEM) is a novel, minimally invasive procedure which allows for a full-thickness myotomy of the stenosed segment, potentially conferring similar anatomical correction to surgical seromyotomy. We present a case of recalcitrant chronic proximal staple line leak in the context of a downstream gastric stenosis managed by G-POEM.