Efficacy and Safety of Endoscopic Antral Myotomy as a Novel Weight Loss Procedure: A Pilot Study

Obesity, defined as body mass index (BMI) greater than 30 kg/m2 in adults, is affecting 30% of the global population and a significant healthcare burden. [1] Obesity has increased dramatically over the last few decades, with over 650 million adults, or 13% of the world's total adult population, diagnosed with the disease in 2016 - a figure that has nearly tripled since 1975.[1] In the U.S the obesity prevalence for U.S. adults increased from 14.1% to 26.7%, or an 89.9% increase between 1993 and 2008.[1,2,3] As a result, current and potential interventions, and treatment strategies to combat obesity have become more important.

The current treatment of obesity involves multiple strategies with combination of non-pharmacologic, pharmacologic, endoscopic, and surgical interventions. There are several FDA-approved pharmacotherapies for the treatment of obesity such as orlistat, phentermine-topiramate, naltrexone-bupropion, liraglutide, and semaglutide. For adults with a body mass index (BMI) of 40 kg/m2 or 35 kg/m2 and obesity-related comorbidity, bariatric surgery can be offered. [4, 5] Endoscopic bariatric and metabolic therapies (EBMT) have emerged as an alternative treatment for patients with obesity with a BMI over 30kg/m2 or 27 kg/m2 with an obesity-related comorbidity. The interest in EBMT is growing given their safety, efficacy, and non-invasive nature. Current FDA-cleared devices that can be used for EBMT include intragastric balloons and suturing devices for endoscopic sleeve gastroplasty (ESG). Additionally, a variety of Endo surgical knifes are approved for tissue dissection such as myotomy.

Gastric interventions used to treat obesity work by interfering with gastric accommodation, breakdown and mixing of food, or gastric emptying. Delaying gastric emptying was shown to be a major mechanism of action for both ESG and IGB which is also correlated with weight loss [6].

Antral peristalsis constitutes an important mechanism for gastric emptying. The antrum also serves as a food sensor which needs to be filled to a certain level before food is pumped into the duodenum. [7] Therefore, targeting the antrum is a feasible strategy to delay gastric emptying, induce satiety, and promote weight loss.

In fact, one of the recently FDA-cleared EBMT devices, the Transpyloric Shuttle (Baronova, MA), focuses on inhibiting the antral pump as its primary mechanism of action. This device consists of two interconnected large and small bulbs, positioned in the antrum and duodenum respectively, that cause intermittent obstruction of the pylorus, leading to a delay in gastric emptying (10).