G-POEM for Treatment of Refractory Gastroparesis

Gastroparesis is a chronic digestive disorder best defined as severe nausea, vomiting,
bloating, and abdominal pain in the setting of objectively delayed gastric emptying without
mechanical gastric outlet obstruction. The most common etiology is idiopathic. Some of the
identifiable etiologies include diabetes and post-surgical.

Endoscopic techniques to reduce pyloric tone mainly consisted of Botulinum toxin injection
but failed to demonstrate significant symptom improvement compared to placebo. Another
endoscopic method was transpyloric stenting which yielded symptomatic relief but is prone to
stent migration and therefore is unlikely to provide a viable long term solution.

Surgical pyloroplasty has shown to be effective in reducing gastroparesis symptoms, but is
associated with a risk of leakage and potential further narrowing of gastric outlet. It also
carried all the risks of general anesthesia and requires advanced laparoscopic suturing
skills. Therefore, the development of a less invasive reliable method of improving gastric
emptying is highly desirable.

An endoscopic submucosal myotomy technique may be applied to divide the pyloric sphincter
without surgical access. Such endoscopic technique may provide the benefits of a natural
orifice procedure, and improve gastric emptying in gastroparetic patients. Gastric Per-Oral
Endoscopic Myotomy (G-POEM) is feasible and can be performed by using techniques similar to
those of esophageal per-oral endoscopic myotomy. Endoscopists who are experienced in
esophageal per-oral endoscopic myotomy should be able to perform G-POEM because both use
similar techniques, principles, and equipment.

The investigators theorize that a subset of patients with refractory gastroparesis, diabetic
gastroparesis or post-surgical gastroparesis, may respond to endoscopic pyloromyotomy.

Inclusion Criteria:

• Adult patient age greater than 18 years old who are undergoing a standard-of-care G-POEM
procedure.

Exclusion Criteria:

- Previous surgery of the esophagus or stomach which has resulted in a resection of the
antrum and pylorus

- Known active gastroesophageal malignancy

- Prior surgical or laparoscopic pyloromyotomy