CHAPTER 85
POEM and G‐POEM

Mary Raina Angeli Fujiyoshi, Haruhiro Inoue, Yusuke Fujiyoshi, Yuto Shimamura, Haruo Ikeda, and Manabu Onimaru

Digestive Diseases Center, Showa University Koto Toyosu Hospital, Tokyo, Japan

The development of peroral endoscopic myotomy (POEM) created a breakthrough in the field of therapeutic endoscopy and it has become a model procedure of third‐space endoscopic procedures. While concerns regarding gastroesophageal reflux disease after POEM remain, preserving the sling and controlling the gastric myotomy length are ways to approach this issue from our perspective. With the feasibility and safety of POEM + fundoplication (POEM+F), managing this issue may be achieved sooner although further studies are still warranted.

As for gastric POEM (G‐POEM), this technique has become an appealing treatment for refractory gastroparesis. G‐POEM has shown a significant reduction in clinical symptoms and improvement in gastric emptying, with clinical outcomes comparable to those of surgical pyloroplasty. Since the learning curve for G‐POEM has not yet been defined, future studies are still required to establish G‐POEM in the treatment algorithm of refractory gastroparesis. Nevertheless, G‐POEM is emerging as a promising treatment option for gastroparesis.

Overall, POEM and G‐POEM, both novel endoscopic procedures for esophageal achalasia and refractory gastroparesis, have shown good clinical outcomes in their respective areas, bringing us to a different level of minimally invasive treatments. These procedures, along with other third‐space endoscopic interventions, may even further revolutionize the field of therapeutic endoscopy to provide patients with optimal care and management.