Gastroesophageal reflux disease, often manifested as chronic heartburn, affects one in twenty people in the Western population. While today's medications effectively suppress symptoms, they do not cure the disease. An implant could serve as an alternative to the effective but complex surgical method (fundoplication). The development stage on which this work is based includes a ring-shaped implant made of biocompatible polymer, which has a porous structure on the inside that allows cells from the esophageal wall to grow into it, thereby preventing the implant from shifting and perforating the esophagus. In this dissertation, the design and surface of the implant were modified to enable cell ingrowth into the pore structure made from a naturally hydrophobic material. Furthermore, a core made of a superelastic nickel-titanium alloy was integrated for the localization of the implant in all imaging procedures. Finally, the applicator for the minimally invasive laparoscopic implantation of this implant, referred to as 'GastroSleeve', was developed.