A device (200) for obstructing a pyloric valve of a stomach, the device comprising: a mobile or inverted cover (204) that includes an extendable tissue coupling portion (205) and an expandable support portion (206), wherein the expandable support portion is adapted to expand in the stomach from a first configuration to a second larger configuration, wherein the support portion in the second configuration prevents the device from passing through the pyloric valve； the device being characterized in that the coupling portion to the extensible tissue is defined along an outer part of the second largest configuration and forms an extensible surface to engage with the stomach tissue adjacent to the pyloric valve； and a positioning member (208) extending from the support portion for passage through the pyloric valve and having a length sufficient to allow the tissue coupling portion to intermittently obstruct the pyloric valve, thereby that during digestion and natural contractions of the stomach, the device moves by contacting and ceasing to be in contact with the pyloric valve so that the gastric contents are allowed to pass through, but with a slowed speed； an inner core (202), wherein the positioning member forms an extension of the inner core (202)； and a distal retention member (210) having a hole (212) or other surface feature, wherein the distal retention member is coupled with a distal end of the positioning member to keep the device in intermittent contact with the valve pyloricUn dispositivo (200) para obstruir una válvula pilórica de un estómago, comprendiendo el dispositivo: una cubierta móvil o invertida (204) que incluye una porción de acoplamiento al tejido extensible (205) y una porción de soporte expandible (206), en donde la porción de soporte expandible está adaptada para expandirse en el estómago desde una primera configuración a una segunda configuración más grande, en donde la porción de soporte en la segunda configuración impide el paso del disposit
