Development of an adjustable prosthesis for the treatment of gastroesophageal reflux: preliminary results in a porcine model.

Dysphagia and recurrent gastroesophageal reflux complicate use of the Angelchik prosthesis. The authors developed an inflatable silicone device, similar to the Angelchik prosthesis, that may allow for the adjustment of the total pressure exerted around the gastroesophageal junction after implantation. To estimate its potential to prevent gastroesophageal reflux in humans, we used a short-term porcine model in which we measured the effective lower esophageal sphincter pressure in 10 anesthetized pigs using a computerized, three dimensional pressure vector volume analysis. Anesthesia and mobilization of the gastroesophageal junction did not modify the three dimensional pressure vector volume at the lower esophageal sphincter. Implantation of the deflated device significantly increased effective lower esophageal sphincter three dimensional pressure vector volume compared with baseline. Inflation of the device with 30 ml of saline further increased lower esophageal sphincter pressure significantly. Deflation of the device returned the pressure to the pre-inflation values. Using an animal model and short-term implantation, this new antireflux device appeared to offer the potential ability to adjust the pressure selectively at the gastroesophageal junction postoperatively. An added future feature of this device may be the ease of insertion using laparoscopic techniques. Long-term animal implantation studies and clinical trials are required to help establish the safety and efficacy of this device in humans.