INTRODUCTION: Gastroesophageal reflux disease is a common condition that often requires long term medical management or elective surgery in the form of fundoplication. Advanced endoscopic techniques can potentially be able to supply a safer alternative for patients with reflux disease. We propose a natural orifice transluminal endoscopic surgical technique that uses a self-approximating submucosal tunnel approach to the mediastinum to perform an anti-reflux procedure. CASE DESCRIPTION/METHODS: An acute porcine model was used for this acute animal feasibility study. Female Yorkshire pigs were kept on a liquid diet for forty eight hours and nothing by mouth eight hours prior to endoscopy. All animals were anesthetized and monitored. A four to five centimeter long submucosal tunnel is created in the posterior esophagus, beginning about ten centimeters above the gastroesophageal junction. From inside the tunnel, the muscles are incised to gain entry into the mediastinum. The esophagus is then followed down to the diaphragmatic hiatus and the right and left crura are located. The aorta, the vagal nerves, and other surrounding structures are identified. Using an overstitch device fitted on a double channel scope, we then suture the crura posteriorly, effecting a cruroplasty. Following the procedure, the animals were euthanized and immediate necropsy was performed to assess for any complications as well as determine the success of the cruroplasty. Esophageal pressure was assessed endoscopically in one animal. DISCUSSION: A submucosal tunnel was successfully achieved in all three animals with safe entry into the mediastinum. Mediastinal and then peri hiatal anatomy was demonstrated in each animal with excellent view of the thoracic aorta, esophagus, right and left vagus nerves, lungs, and the diaphragmatic crura. Endosuturing was successful with effective cruroplasty in all three animals without complications. Necropsy showed that sutures were in correct anatomical location without signs of procedural complication. We conclude that it is entirely possible to access the diaphragmatic hiatus and perform endoscopic cruroplasty for the potential treatment of reflux disease. A survival study aimed at developing a full-fledged anti reflux procedure is currently underway. We speculate that a trans-esophageal approach can provide an easy and safe treatment option for selected patients suffering from reflux disease. Watch the video: http://bit.ly/2JQiEaF