Gastric bypass pouch and stoma reduction using a transoral endoscopic anchor placement system: A feasibility study

Background: Weight regain after Roux-en-Y gastric bypass may be caused by pouch enlargement or dilatation of the gastrojejunostomy (stoma). In order to avoid the substantial morbidity of revisional bariatric surgery, investigators have recently demonstrated the feasibility of reducing stoma diameter using transoral endoscopic suturing techniques. Our aim was to demonstrate the feasibility of performing both pouch and stomal reduction using transoral endoscopically placed tissue anchors in an ex vivo and acute animate model. Methods: Part I: We created an ex vivo model of a dilated gastric pouch and stoma using four explanted porcine stomachs. The stomach was divided to create an upper pouch of approx. 100 ml volume, which was reconnected to the lower portion of the stomach (gastric remnant) via an anastomosis of 18 to 20 mm diameter. Endoscopically placed anchors were then used to create plications of the stoma and reduce its diameter. In two stomachs, anchor plications were also used to decrease pouch volume. Pouch volumes and stoma diameters were measured pre- and post-procedure. Part II: A similar experimental model was created in vivo using three pigs. Anchors were placed in the stoma and pouch. The animals were immediately sacrificed and similar measurements were obtained. Results: In the ex vivo model, stoma diameter was successfully reduced in all four stomachs by a mean of 8 mm (41%). This represented a mean decrease in cross-sectional area of 65%. Pouch volume was reduced by a mean of 28 ml (30%) in two stomachs. Stomal plications were successfully placed in two of the live animals, with a mean stoma diameter reduction of 11.5 mm (53%). Feasibility of pouch reduction using plicating anchors was confirmed. Conclusions: This is the first study to demonstrate the feasibility of using endoscopically placed tissue anchors to reduce both stoma diameter and pouch volume. This technique may ultimately be clinically useful in treating weight regain after gastric bypass surgery.