The Causes of Gastroesophageal Reflux after Laparoscopic Sleeve Gastrectomy: Quantitative Assessment of the Structure and Function of the Esophagogastric Junction by Magnetic Resonance Imaging and High-Resolution Manometry

Background: The incidence of de novo gastroesophageal reflux disease (GERD) after LSG is substantial. However, an objective correlation with the structural gastric and EGJ changes has not been demonstrated yet. We aimed to prospectively evaluate the effects of laparoscopic sleeve gastrectomy (LSG) on the structure and function of the esophagogastric junction (EGJ) and stomach. Methods: Investigations were performed before and after > 50% reduction in excess body weight (6–12 months after LSG). Subjects with GERD at baseline were excluded. Magnetic Resonance Imaging (MRI), high-resolution manometry (HRM), and ambulatory pH-impedance measurements were used to assess the structure and function of the EGJ and stomach before and after LSG. Results: From 35 patients screened, 23 (66%) completed the study (age 36 ± 10 years, BMI 42 ± 5 kg/m2). Mean excess weight loss was 59 ± 18% after 7.1 ± 1.7-month follow-up. Esophageal acid exposure (2.4 (1.5–3.2) to 5.1 (2.8–7.3); p = 0.040 (normal < 4.0%)) and reflux events increased after surgery (57 ± 24 to 84 ± 38; p = 0.006 (normal < 80/day)). Esophageal motility was not altered by surgery; however, intrabdominal EGJ length and pressure were reduced (both p < 0.001); whereas the esophagogastric insertion angle (35° ± 11° to 51° ± 16°; p = 0.0004 (normal < 60°)) and esophageal opening diameter (16.9 ± 2.8 mm to 18.0 ± 3.7 mm; p = 0.029) were increased. The increase in reflux events correlated with changes in EGJ insertion angle (p = 0.010). Patients with > 80% reduction in gastric capacity (TGV) had the highest prevalence of symptomatic GERD. Conclusion: LSG has multiple effects on the EGJ and stomach that facilitate reflux. In particular, EGJ disruption as indicated by increased (more obtuse) esophagogastric insertion angle and small gastric capacity were associated with the risk of GERD after LSG. clinicaltrials.gov: NCT01980420