Gastric Peroral Endoscopic Myotomy

Abstract

Gastroparesis (GP) is a syndrome characterized by delayed gastric emptying in the absence of mechanical obstruction of the stomach or proximal small bowel. Currently available dietary and medical therapies are limited and have suboptimal efficacy. Pylorus-directed therapies have showed promising results. Gastric peroral endoscopic myotomy (G-POEM) has been reported for the treatment of GP refractory to standard therapy with promising results. This article reviews the current applications and results of G-POEM for the treatment of refractory GP.

Outcomes of per oral endoscopic pyloromyotomy in gastroparesis worldwide

“…Extent and depth of pyloromyotomy may vary depending on endoscopist’s preference and how well the pyloric ring can be identified in the submucosal tunnel. Most report suggested performing the procedure in supine position as it will be easier to orient the scope direction but left lateral decubitus position may be required when a large gastric loop is present[49]. Prolonged period of clear liquid diet for 2-3 d both before and after POP was recommended as a routine pre- and post-procedure protocol to maximize visualization and reduce the risk of procedure-related infection[2,49].…”

“…Other technical variations among endoscopists include site of mucosal entry (lesser vs greater curve), mucosotomy closure tools (clips vs suture), depth of pyloromyotomy, and the need for fluoroscopy[2,45,50-52]. Though general anesthesia is recommended in all studies but conscious sedation in endoscopy suite can be safely and successfully performed as well[49]. Intravenous antibiotic prophylaxis is routinely administered though there is no high-quality evidence to support the practice.…”

“…However, subsequent studies verified that submucosal tunnel can be safely and effectively performed regardless of the site of mucosal entry and selective circular myotomy can achieve clinical success without the perforation risk in full thickness myotomy[41,47,48,55,56]. While mucosotomy on the greater curve makes the scope more in a neutral position and allows greater maneuverability, performing a mucosal entry on the lesser curve has its own advantages that are: (1) Shorter scope length to mucosotomy site by minimizing the gastric loop; (2) shorter length of the submucosal tunnel, reducing the risk of tunneling in the wrong direction; and (3) the procedural field is not a dependent area when the patient is on supine position, therefore blood and food would not interfere with the endoscopic visualization[48,49,55].…”

“…Carbon dioxide, which is absorbed 160 times faster than nitrogen gas in room air is essential to minimize this risk[57]. For hemostasis, soft coagulation mode (ERBE, Germany) for ablation of small vessels with a diameter less than 5 mm and coag-grasper (FD-411QR; Olympus, Japan) for bleeding control from a large vessel are generally used[49,55,56].…”

“…Since Kawai and colleagues proved that the concept of pyloromyotomy can be performed endoscopically using submucosal technique similar to that of POEM procedure in 2014[42], multiple centers have performed POP for patients with refractory gastroparesis. Most studies have been reported from The United States and France with some reports from Korea, Brazil, Australia, India, Venezuela, Mexico, and Czech Republic[2,37,40,43,45,46,48,49,54-56,58,59]. This may be in part due to high prevalence of the disease with only one approved medication for symptomatic treatment in the United States.…”