Flap Valve-Preserving Vertical Sleeve Gastrectomy (INNOVATE-VSG): Clinical Trial Study Protocol.

Abstract

Background: Conventional vertical sleeve gastrectomy (cVSG), the most commonly performed bariatric surgery, is associated with low complications, durable weight loss, and significant improvement of many obesity-related comorbidities. However, numerous studies have reported that patients who underwent the cVSG have worsening or new onset (de novo) gastroesophageal reflux disease (GERD) which could be related to a negative effect of the operative procedure on the geometry of the gastroesophageal junction impacting on the function of the native gastroesophageal valve. It is imperative to innovate the cVSG procedure because chronic GERD is a debilitating condition associated with increased risk for Barrett's esophagus and esophageal cancer. INNOVATE-VSG aims to test whether a modified flap valve-preserving VSG (fvpVSG), compared to cVSG, will be associated with improvement of preexisting GERD.

Methods: The fvpVSG incorporates the following surgical modifications that strengthen the antireflux barrier: achieving 3 cm intrabdominal esophageal length; repair of the diaphragmatic crura; and preservation of 3 cm length of gastric fundus/cardia during the sleeve gastrectomy procedure which will be used to symmetrically wrap around the distal esophagus (120-160° wrap) to restore the naturally occurring gastroesophageal valve. A total of 44 obese patients (BMI 35-50 kg/m²) with pathologic GERD, confirmed by abnormal acid exposure time (AET), will be randomly assigned to cVSG or fvpVSG in this pilot randomized clinical trial at two academic sites. The primary outcome is the change in AET at 6-9 months after surgery. Secondary outcomes include changes in the lower esophageal sphincter pressure, compliance of the esophagogastric junction, weight loss, and quality of life.

Discussion: Data generated from the INNOVATE-VSG trial will be used to design a larger multi-center randomized clinical trial to confirm the value of preserving a functioning gastroesophageal valve following sleeve gastrectomy.