Clinic for Visceral Surgery and Medicine, University Hospital Inselspital Bern, Switzerland

1. Electrical Stimulation of the Lower Esophageal Sphincter improves Gastroesophageal Reflux Disease in Patients after Laparoscopic Sleeve Gastrectomy • Clinic for Visceral Surgery and Medicine, University Hospital Inselspital Bern, Switzerland • Esophageal Surgery Program, University of Favaloro, Buones Aires , Argentina • Surgery, CCO Obesidad, Santiago, Chile • EvangelischesKrankenhaus , Castrop-Rauxel, Germany • St George Private Hospital, Kogarah, NSW, Australia • Strathfield Private Hospital, Strathfield, NSW, Australia • University of Maastricht, Maastricht, Netherlands Borbély, Yves M.1; Nieponice, Alejandro2; Rodriguez, Leonardo Antonio3; Schulz, Henning G.✝4; Ortiz, Camila2; Talbot, Michael5; Martin, David6; Bouvy, Nicole D.7

2. Background Laparoscopic Sleeve Gastrectomy (LSG): • most commonly performed bariatric procedure worldwide • technical simplicity • low morbidity • access to biliary tree, stomach, duodenum • comparable results to RYGB • can result in de novo GERD and may worsen preexisting GERD

3. Background LSG patients with GERD not well controlled with PPI: • standard treatment option is switch to more invasive, anatomy-altering Roux-Y Gastric Bypass • Lower Esophageal Sphincter (LES) electrical stimulation therapy has shown to improve outcomes in GERD patients Aim of this study: • to evaluate safety and efficacy of LES stimulation in LSG patients with GERD not controlled with maximum dose PPI therapy

4. Methods • international patient registry prospectively tracking outcomes in GERD patients treated with LES electrical stimulation • Patients with LSG-associated GERD with bothersome symptoms on maximum PPI dose underwent LES stimulator implant procedure and were enrolled in the registry • Electrical stimulation was delivered at 5mA, 220uSec pulse in 12, 30 minute sessions daily • GERD outcomes pre and post-stimulation were evaluated • GERD-HRQL • Esophageal Acid Exposure (after 6-12 months) • PPI medication Use • Adverse events – Serious and Non-Serious

6. Results: demographic data, safety • 22 patients (13 female, 59%) • median age 47.5y (min 25 – max 76) • median BMI 31.7kg/m2 (22.5 – 57.6) • during follow-up 30.3kg/m2 • treated at 9 centers, 05/14 - 10/16 • median follow-up 15.5 months (6 – 36) • no serious adverse event relatedto device or procedure • no dysphagia or other GI side effects

7. Results: PPI use (cumulative dose per day) • note: 2 patients with chronic steroid use, 1 patient post-renal transplantation • median 2x40mg/d @baseline, no medication at follow-up, p<0.01 dosage equivalents to 40mg Pantoprazol

8. Results: follow-up of typical GERD-symptoms • heartburn/regurgitation overall • heartburn/reg when lying down • heartburn/reg when standing up • heartburn/reg after meals • affecting meals? • affecting sleep? • difficulty swallowing • pain assoc with swallowing • bloating/gassy feeling • medication affects daily life? • 0: no symptoms << 5: incapacitating • max 50 points • Velanovic V, J GastrointestSurg 1998; 2:141 median 32 @baseline (on PPI), @last follow-up 9 (off-PPI), p<0.01

9. Results: esophageal acid exposure • normalization (esophageal pH<4 <4%) in 10 patients (45%) • median %time pH <4 @baseline 12.7, @follow-up 6.3 (p=0.003) • 24h-off PPI- pH-metry • median follow-up 9 months • solid line represents median • dotted line at 4%

10. Conclusion Electrical stimulation of LES (preliminary data): • is safe • has no GI side-effects • results in significant improvement of GERD symptoms and esophageal acid exposure in post-LSG patients • most patients are off PPI therapy with remaining taking PPI at reduced dose • expands bariatric armentarium and offers solution for patients with post-LSG GERD impossible to undergo RYGB