To evaluate the effect and explore the mechanism of action behind the potential effect of Stretta® on GERD after SG.

Gastroesophageal reflux disease (GERD), i.e. the occurrence of troublesome symptoms or lesions as a consequence of retrograde flow of gastric contents into the esophagus, is one of the most prevalent gastrointestinal disorders. Obesity, defined by a body mass index (BMI) of ≥ 30 kg/m2, is an increasingly important problem in the Western world and a well-known risk factor for GERD related symptoms and esophagitis. Possible underlying mechanisms include an increased gastroesophageal pressure gradient, upward positional shift of the lower esophageal sphincter (LES) and increased occurrence of transient LES relaxations (TLESRs) after a meal.

Bariatric surgery has emerged as a highly effective treatment for obesity and its associated metabolic complications. Roux-en-Y gastric bypass and sleeve gastrectomy (SG) currently account for the majority of the procedures. Several studies have reported improvement of GERD after gastric bypass and SG, probably through a combination of reduction of the acid-producing gastric mucosa and weight loss. However, in up to 34% of patients who underwent SG, de novo GERD or worsening of pre-existent GERD becomes evident, which established baseline GERD symptoms one of the few relative contra-indications for SG in many centers. Several post-operative alterations have been hypothesized to explain the increased incidence of GERD after SG: increased incidence of hiatal hernia due to the sleeve formation, dissection of the phreno-esophageal ligament, intrathoracic sleeve migration, increased intragastric pressure due to decreased gastric compliance and disruption of the competency of the esophagogastric junction (EGJ).

Despite the fact that the majority of patients will respond to proton pump inhibitor (PPI) therapy, a significant proportion of patients continue to experience regurgitation and/or heartburn despite acid suppression although treatment outcome data are largely missing in the literature. These patients with refractory GERD symptoms after SG pose a challenge to surgeons and gastroenterologists since the postoperative anatomy does not allow classic fundoplication procedures.

Stretta® (Mederi RF LLC, Houston TX, USA) is an endoscopic anti-reflux procedure using the delivery of radiofrequency energy to the LES. Stretta® is supported by the Society of American Gastrointestinal Endoscopic Surgeons (SAGES, ASGE and NICE) for the treatment of GERD in selected patients and is long-term cost-effective. Several controlled studies and a meta-analysis have reported improved symptoms after Stretta® although the effect on esophageal acid exposure time is inconsistent. Stretta® decreases the compliance of the EGJ without inducing fibrosis since the effect was reversed by administration of a nitric oxide donor and decreased sensitivity to distal acid perfusion. However, studies evaluating the symptomatic benefit of Stretta® in patients after SG are lacking, which is the primary goal of our study (primary endpoint). With the secondary endpoints, the effect of Stretta® will also be investigated on various aspects, which will provide an insight in the mechanism of action behind the potential effect of the intervention.

Inclusion Criteria:

1. 18 to 65 years old;
2. History of typical GERD symptoms (heartburn or regurgitation) during PPI treatment, at least 3 times per week for 12 weeks ('refractory GERD') or unwillingness to take/continue PPIs. The symptoms can be de novo (onset after sleeve gastrectomy) or pre-existing (as documented by medication use, findings during endoscopy or medical history);
3. In case of refractory GERD symptoms during PPI treatment the following criteria need to be fulfilled: Pathological catheter-based 24h pH-MII monitoring off-PPI (>6% of total time pH<4 and/or number of reflux episodes >80 (irrespective of acidity) or positive symptom association probability (SAP) for typical reflux symptoms) based on the Lyon consensus (23);
4. More than 12 months after sleeve gastrectomy;
5. Willing to take contraceptive measurements.

Exclusion Criteria:

1. Hiatal hernia of >2cm as determined during HRiM (based on Chicago Classification v3.0. (24)) and/or endoscopy or hiatal hernia repair;
2. Esophagitis LA classification grade C or D during gastroscopy off-PPI;
3. Circumferential Barrett's esophagus >1cm (columnar lined esophageal mucosa with intestinal metaplasia) or history of ablation of Barrett's esophagus;
4. Esophageal or fundus varices during gastroscopy;
5. Esophageal strictures during gastroscopy;
6. Abnormalities in sleeve (e.g. sleeve migration) observed during gastroscopy and/or barium test;
7. Known cirrhosis or portal hypertension from other causes;
8. History of surgery to the upper gastrointestinal tract other than sleeve gastrectomy, including redo after previous bariatric surgery;
9. Autoimmune or a connective tissue disorder (scleroderma, dermatomyositis, Calcinosis-Raynaud's-Esophagus Sclerodactily Syndrome (CREST), Sjogren's Syndrome, etc.);
10. Achalasia, EGJ-outflow obstruction, jackhammer esophagus or absent contractility as defined by the 3rd revision of the Chicago classification for primary esophageal motility disorders24 assessed during HRiM with meal (see study protocol (25));
11. Significant cardiopulmonary or other comorbidity precluding safe sedation;
12. Pacemaker or implanted cardiac defibrillator;
13. Coagulopathy or use of anticoagulants;
14. Pregnancy or breastfeeding
15. Unable or unwilling to consent for an invasive procedure.

In the first period are the patients and investigators blinded. Afterwards there is an open label period.