Pyloric anchor and gastrointestinal tube

A bypass tube (14) having a distal end for placement within the small intestine of a patient and a proximal end for placement near or at the pylorus. The tube includes a pyloric anchor (16) including a gastric anchor (22) for anchoring the proximal end of the tube relative to the pyloric to prevent distal movement. The gastric anchor includes a tubular balloon (24) and a self-expanding structure (22a, 22b) for biasing a radially inner wall and/or radially outer wall of the tubular balloon outwardly toward its expanded form. The self-expanding structure includes a first section including an annular hub or collar (22a) having a first resistance to inward collapse and a second section including a plurality of independently deflectable beams or branches (22b) extending from the first section and having a second smaller resistance to inward collapse. A pyloric anchor that twists about its axis when expanded, and a non-helical reinforcement of the flexible tube in the small intestine are also described. 一种旁路管(14)，其