Resistive Anti-Obesity Devices

Abstract

A patient is provided with an increased sense of satiety by increasing resistance to the outflow of food from the stomach and through the intestines. Stomach emptying may be slowed with devices implantable within the gastrointestinal tract below the stomach. Implants are preferably removable and can include artificial strictures that may be adjustable to vary the rate of stomach emptying. Slowing gastric emptying may induce satiety for a longer period and may therefore reduce food consumption. Many of the embodiments include intestinal liners or sleeves, but they need not. The resistor concept may be applied to a simple anchor and resistor without a long liner.

1 . A gastrointestinal implant comprising:
 an anchor configured for implantation within a gastrointestinal tract of an animal at a position at or distal to the animal's pylorus; and an artificial stricture in communication with the anchor, the artificial stricture comprising a hole in a substantially impermeable blocking membrane, the hole being 5 mm or less in diameter, the membrane being attached to the anchor in a taught manner to limit axial extent of the membrane beyond the distal end of the anchor, the anchor removably securing the artificial stricture in position and the artificial stricture retarding the outflow of chyme from the stomach through the hole.   
     
     
         2 . The implant of  claim 1 , wherein the membrane is elastomeric and is able to expand under pressure from the chyme. 
     
     
         3 . The implant of  claim 1 , wherein the membrane comprises plastically deformable material. 
     
     
         4 . The implant of  claim 1 , wherein the hole is between 3 mm and 5 mm in diameter. 
     
     
         5 . The implant of  claim 1 , wherein the hole is adjustable to selectively vary resistance provided thereby to the outflow of chyme from the stomach. 
     
     
         6 . The implant of  claim 1 , further comprising an elongated liner defining a lumen through which chyme passes. 
     
     
         7 . The implant of  claim 6 , wherein the artificial stricture is positioned within the liner. 
     
     
         8 . The implant of  claim 1 , wherein the anchor is self-expanding and has a relaxed diameter of at least 40 mm. 
     
     
         9 . The implant of  claim 8 , wherein the anchor is self-expanding and has a relaxed diameter of at least 45 mm. 
     
     
         10 . The implant of  claim 8 , wherein the anchor is a wave anchor. 
     
     
         11 . The implant of  claim 10 , wherein the wave anchor has a single wave in a single revolution. 
     
     
         12 . The implant of  claim 1 , wherein the anchor comprises at least one barb adapted for insertion into muscular tissue of the gastrointestinal tract. 
     
     
         13 . The implant of  claim 1 , wherein the anchor defines a lumen through which chyme passes, the membrane being configured to cover the cross-sectional area of the lumen. 
     
     
         14 . A gastrointestinal implant comprising:
 a self-expanding wave anchor configured for implantation within a gastrointestinal tract of an animal at or distal to the animal's pylorus, the wave anchor having a relaxed diameter of at least 40 mm; and   a resistive element in communication with the wave anchor, the anchor removably securing the resistive element in position and the resistive element retarding the outflow of chyme from the stomach.   
     
     
         15 . The implant of  claim 14 , wherein the wave anchor has a relaxed diameter of at least 45 mm. 
     
     
         16 . The implant of  claim 14 , wherein the wave anchor comprises at least one barb adapted for insertion into muscular tissue of the gastrointestinal tract. 
     
     
         17 . The implant of  claim 14 , wherein the wave anchor has a single wave in a single revolution. 
     
     
         18 . The implant of  claim 14 , wherein the resistive element comprises a substantially impermeable blocking membrane having a hole therein. 
     
     
         19 . The implant of  claim 18 , wherein the membrane is attached to the anchor in a taught manner to limit axial extent of the membrane beyond the distal end of the anchor. 
     
     
         20 . The implant of  claim 18 , wherein the membrane is elastomeric and is able to expand under pressure from the chyme. 
     
     
         21 . The implant of  claim 18 , wherein the membrane comprises plastically deformable material. 
     
     
         22 . The implant of  claim 18 , wherein the hole is adjustable to selectively vary resistance provided thereby to the outflow of chyme from the stomach. 
     
     
         23 . The implant of  claim 18 , wherein the hole is 5 mm or less in diameter. 
     
     
         24 . The implant of  claim 18 , further comprising an elongated liner defining a lumen through which chyme passes. 
     
     
         25 . The implant of  claim 24 , wherein the membrane is positioned within the liner.