Faculty Bibliography

Peroral endoscopic myotomy (POEM) for achalasia (sometimes also referred as E-POEM to distinguish it from its offshoots such as G-POEM for gastroparesis or Z-POEM for Zenker's diverticula) is the newest treatment modality but has already been well validated as a standard intervention for esophageal achalasia. POEM was conceived as a Natural Orifice Transluminal Endoscopic Surgery (NOTES) procedure with an incisionless, endoscopic approach to myotomy. It matches or exceeds the efficacy of its surgical counterpart, the laparoscopic Heller myotomy, with superiority for type III (spastic) achalasia. There are issues however, especially regarding GERD after POEM that will likely result in further refinements of technique and post-procedural care. We will summarize the current status of POEM including description of technique variations and review of comparative data vis a vis Heller myotomy (HM) and pneumatic dilation (PD) and we will delve into some of the seminal issues around GERD assessment, management and prevention.

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.

BACKGROUND AND AIMS/OBJECTIVE:Closure of endoscopic resection defects can be achieved with through-the-scope clips, over-the-scope clips or endoscopic suturing. However, these devices are often limited by their inability to close large, irregular, and difficult to reach defects. Thus, we aimed to assess the feasibility and safety of the novel through-the-scope suture-based closure system that was developed to overcome these limitations. METHODS:This is a retrospective multicenter study involving 8 centers in the United States. Primary outcomes included feasibility and safety of early use of the device. Secondary outcomes included assessment of need for additional closure devices, prolonged procedure time, and technical feasibility of performing the procedure with an alternative device(s). RESULTS:A total of 93 patients (48.4% female) with mean age 63.6 ± 13.1 years were included. Technical success was achieved in 83 patients (89.2%) and supplemental closure was required in 24.7% (n=23) of patients with a mean defect size of 41.6 ± 19.4 mm. Closure with an alternative device was determined to be impossible in 24.7% of patients due to location, size, or shape of the defect. The use of the tack and suture device prolonged the procedure in 8.6% of the cases but was considered acceptable. Adverse events occurred in 2 patients (2.2%) over a duration of follow-up of 34 days (interquartile range: 13-93.5 days) and were mild and moderate in severity. No serious adverse events or procedure-related deaths occurred. CONCLUSIONS:The novel endoscopic through-the-scope tack and suture system is safe, efficient, and permits closure of large, and irregularly shaped defects that were not possible with predicate devices.

BACKGROUND AND AIMS/OBJECTIVE:Peroral endoscopic myotomy (POEM) is becoming the treatment of choice for achalasia. Data beyond 3 years are emerging but limited. We herein report our 10-year experience, focusing on long-term efficacy and safety including the prevalence, management, and sequelae of postoperative reflux. METHODS:This was a single-center prospective cohort study. RESULTS:Six hundred ten consecutive patients received POEM from October 2009 to October 2019 for type I achalasia in 160 (26.2%), II in 307 (50.3%), III in 93 (15.6%), untyped achalasia in 25 (4.1%), and nonachalasia disorders in 23 (3.8%). Two hundred ninety-two (47.9%) patients had prior treatment(s). There was no aborted POEM. Median operation time was 54 minutes. Accidental mucosotomies occurred in 64 (10.5%) and clinically significant adverse events (csAEs) in 21 (3.4%) patients. There were no adverse events (AEs) leading to death, surgery, interventional radiology interventions/drains, or altered functional status. At a median follow-up of 30 months, 29 failures occurred, defined as postoperative Eckardt score >3 or need for additional treatment. The Kaplan-Meier clinical success estimates at year 1, 2, 3, 4, 5, 6, and 7 were 98%, 96%, 96%, 94%, 92%, 91%, and 91%, respectively. These are highly accurate estimates because only 13 (2%) patients were missing follow-up assessments. One hundred twenty-five (20.5%) patients had reflux symptoms more than once per week. At a median of 4 months, the pH study was completed in 406 (66.6%) patients and was positive in 232 (57.1%) and endoscopy in 438 (71.8%) patients and showed reflux esophagitis in 218 (49.8%), mostly mild. CONCLUSION/CONCLUSIONS:POEM is exceptionally safe and highly effective on long-term follow-up, with >90% clinical success at ≥5 years.

BEST PRACTICE ADVICE 1: For all procedures, especially procedures carrying an increased risk for perforation, a thorough discussion between the endoscopist and the patient (preferably together with the patient's family) should include details of the procedural techniques and risks involved. BEST PRACTICE ADVICE 2: The area of perforation should be kept clean to prevent any spillage of gastrointestinal contents into the perforation by aspirating liquids and, if necessary, changing the patient position to bring the perforation into a non-dependent location while minimizing insufflation of carbon dioxide to avoid compartment syndrome. BEST PRACTICE ADVICE 3: Use of carbon dioxide for insufflation is encouraged for all endoscopic procedures, especially any endoscopic procedure with increased risk of perforation. If available, carbon dioxide should be used for all endoscopic procedures. BEST PRACTICE ADVICE 4: All endoscopists should be aware of the procedures that carry an increased risk for perforation such as any dilation, foreign body removal, any per oral endoscopic myotomy (Zenker's, esophageal, pyloric), stricture incision, thermal coagulation for hemostasis or tumor ablation, percutaneous endoscopic gastrostomy, ampullectomy, endoscopic mucosal resection (EMR), endoscopic submucosal dissection (ESD), endoluminal stenting with self-expanding metal stent (SEMS), full-thickness endoscopic resection, endoscopic retrograde cholangiopancreatography (ERCP) in surgically altered anatomy, endoscopic ultrasound (EUS)-guided biliary and pancreatic access, EUS-guided cystogastrostomy, and endoscopic gastroenterostomy using a lumen apposing metal stent (LAMS). BEST PRACTICE ADVICE 5: Urgent surgical consultation should be highly considered in all cases with perforation even when endoscopic repair is technically successful. BEST PRACTICE ADVICE 6: For all upper gastrointestinal perforations, the patient should be considered to be admitted for observation, receive intravenous fluids, be kept nothing by mouth, receive broad-spectrum antibiotics (to cover Gram-negative and anaerobic organisms), nasogastric tube (NGT) placement (albeit some exceptions), and surgical consultation. BEST PRACTICE ADVICE 7: For upper gastrointestinal tract perforations, a water-soluble upper gastrointestinal series should be considered to confirm the absence of continuing leak at the perforation site before initiating a clear liquid diet. BEST PRACTICE ADVICE 8: Endoscopic closure of esophageal perforations should be pursued when feasible, utilizing through-the-scope clips (TTSCs) or over-the-scope clips (OTSCs) for perforations <2 cm and endoscopic suturing for perforations >2 cm, reserving esophageal stenting with SEMS for cases where primary closure is not possible. BEST PRACTICE ADVICE 9: Endoscopic closure of gastric perforations should be pursued when feasible, utilizing TTSCs or OTSCs for perforations <2 cm and endoscopic suturing or combination of TTSCs and endoloop for perforations >2 cm. BEST PRACTICE ADVICE 10: For large type 1 duodenal perforations (lateral duodenal wall tear >3 cm), being cognizant of the difficulty in closing them endoscopically, urgent surgical consultation should be made while the feasibility of endoscopic closure is assessed. BEST PRACTICE ADVICE 11: Because type 2 periampullary (retroperitoneal) perforations are subtle and can be easily missed, the endoscopist should carefully assess the gas pattern on fluoroscopy to avoid delays in treatment and request a computed tomography scan if there is a concern for such a perforation; identified perforations of this type at the time of ERCP may be closed with TTSCs if feasible and/or by placing a fully covered SEMS into the bile duct across the ampulla. BEST PRACTICE ADVICE 12: For the management of large duodenal polyps, endoscopic mucosal resection (EMR) should only be performed by experienced endoscopists and endoscopic submucosal dissection (ESD) only by experts because both EMR and ESD in the duodenum require proficiency in resection and mucosal defect closure techniques to manage immediate and/or delayed perforations (caused by the proteolytic enzymes of the pancreas). BEST PRACTICE ADVICE 13: Endoscopists should be aware that colon perforations occurring during diagnostic colonoscopy are most commonly located in the sigmoid colon due to direct trauma from forceful advancement of the colonoscope. Such tears recognized at the time of colonoscopy may be closed by TTSCs or OTSCs if the bowel preparation is good and the patient is stable. BEST PRACTICE ADVICE 14: Although colon perforation is responsive to various endoscopic tools such as TTSC, OTSC, and endoscopic suturing, perforations in the right colon, especially in the cecum, have been relegated to using only TTSCs because of inability to reach the site of the perforation with an endoscopic suturing device or OTSC if the colon is tortuous or unclean. Recently a new suture-based device for defect closure has been introduced allowing deep submucosal and intramuscular enhanced fixation through a standard gastroscope or colonoscope. BEST PRACTICE ADVICE 15: Patients with perforations who are hemodynamically unstable or who have suffered a delayed perforation with peritoneal signs or frank peritonitis should be surgically managed without any attempt at endoscopic closure. BEST PRACTICE ADVICE 16: In any adverse event including perforation, it is paramount to ensure accurate documentation, prompt discussion with the patient and family, and swift reporting to the quality officer (or equivalent) and risk management team of the institution (in major adverse events).