Anchors and methods for intestinal bypass sleeves

CROSS-REFERENCE TO RELATED APPLICATIONS

0001This application claims the benefit under 35 U.S.C. section 119(e) of U.S. provisional patent application 61/462,156, filed Jan. 28, 2011, and U.S. provisional patent application 61/519,207, filed May 24, 2011, both of which are herein incorporated by reference in their entirety. This application is a continuation-in-part of each of the following applications, each of which are herein incorporated by reference in their entirety: (1) U.S. patent application Ser. No. 12/752,697, filed Apr. 1, 2010, which claims the benefit of U.S. provisional patent application 61/211,853, filed Apr. 3, 2009; (2) U.S. patent application Ser. No. 12/833,605, filed Jul. 9, 2010, which claims the benefit of U.S. provisional patent application 61/270,588, filed Jul. 10, 2009; (3) U.S. patent application Ser. No. 12/986,268, filed Jan. 7, 2011, which claims the benefit of U.S. provisional patent application 61/335,472, filed Jan. 7, 2010; and (4) U.S. patent application Ser. No. 13/298,867, filed Nov. 17, 2011, which claims the benefit of U.S. provisional patent application 61/458,060, filed Nov. 17, 2010.

TECHNICAL FIELD

0002This invention generally relates to implants placed within gastrointestinal systems, including the esophagus, the stomach and the intestines. In particular it relates to implant systems having components implantable and removable using endoscopic techniques for treatment of obesity, diabetes, reflux, gastroparesis and other gastrointestinal conditions.

BACKGROUND

0003Bariatric surgery procedures, such a sleeve gastrectomy, the Rouen-Y gastric bypass (RYGB) and the bileo-pancreatic diversion (BPD), modify food intake and/or absorption within the gastrointestinal system to effect weight loss in obese patients. These procedures affect metabolic processes within the gastrointestinal system, by either short circuiting certain natural pathways or creating different interaction between the consumed food, the digestive tract, its secretions and the neuro-hormonal system regulating food intake and metabolism. In the last few years there has been a growing clinical consensus that obese patients who undergo bariatric surgery see a remarkable resolution of their type-2 Diabetes Mellitus (T2DM) soon after the procedure. The remarkable resolution of diabetes after RYGB and BPD typically occurs too fast to be accounted for by weight loss alone, suggesting there may be a direct impact on glucose homeostasis. The mechanism of this resolution of T2DM is not well understood, and it is quite likely that multiple mechanisms are involved.

0004One of the drawbacks of bariatric surgical procedures is that they require fairly invasive surgery with potentially serious complications and long patient recovery periods. In recent years, there is an increasing amount of ongoing effort to develop minimally invasive procedures to mimic the effects of bariatric surgery using minimally invasive procedures. One such procedure involves the use of gastrointestinal implants that modify transport and absorption of food and organ secretions. For example, U.S. Pat. No. 7,476,256 describes an implant having a tubular sleeve with anchoring barbs, which offer the physician limited flexibility and are not readily removable or replaceable. Moreover, stents with active fixation means, such as barbs that deeply penetrate into surrounding tissue, may potentially cause tissue necrosis and erosion of the implants through the tissue, which can lead to complications, such as bacterial infection of the mucosal tissue or systemic infection. Also, due to the intermittent peristaltic motion within the digestive tract, implants such as stents have a tendency to migrate.

0005Gastroparesis is a chronic, symptomatic disorder of the stomach that is characterized by delayed gastric emptying in the absence of mechanical obstruction. The cause of gastroparesis is unknown, but it may be caused by a disruption of nerve signals to the intestine. The three most common etiologies are diabetes mellitus, idiopathic, and postsurgical. Other causes include medication, Parkinson's disease, collagen vascular disorders, thyroid dysfunction, liver disease, chronic renal insufficiency, and intestinal pseudo-obstruction. The prevalence of diabetic gastroparesis (DGP) appears to be higher in women than in men, for unknown reasons.

0006Diabetic gastroparesis affects about 40% of patients with type 1 diabetes and up to 30% of patients with type 2 diabetes and especially impacts those with long-standing disease. Both symptomatic and asymptomatic DGP seem to be associated with poor glycemic control by causing a mismatch between the action of insulin (or an oral hypoglycemic drug) and the absorption of nutrients. Treatment of gastroparesis depends on the severity of the symptoms.

SUMMARY

0007According to various embodiments, the present invention provides for an apparatus and method to place and anchor an intestinal bypass sleeve within the pyloric antrum, pylorus, duodenum and jejunum. The gastrointestinal implant herein disclosed can be inserted endoscopically (when the device is loaded into a delivery catheter) through the mouth, throat, stomach and intestines. The gastrointestinal implant device includes a flexible thin-walled sleeve and an expandable anchor attached to the proximal end of the sleeve; secondary anchors may also anchor other portions of the thin-walled sleeve.

0008The present invention herein disclosed (with a short bypass sleeve or no bypass sleeve) can also be used to hold open the pylorus and may help to reduce the symptoms of gastroparesis, by allowing the stomach contents to exit the stomach easier through the pylorus into the duodenum. An active pumping means may also be attached to the expandable anchor to actively pump the stomach contents from the pyloric antrum into the duodenum.

BRIEF DESCRIPTION OF THE DRAWINGS

0009<figref idref="DRAWINGS">FIG. 1</figref> is a cross-sectional view of a portion of the digestive tract in a human body with an intestinal bypass sleeve implanted in the duodenum from the pylorus to the ligament of treitz. The sleeve is held in place at the pylorus by an expandable anchor that anchors on the pylorus.

0010<figref idref="DRAWINGS">FIG. 2</figref> is a cross-sectional view of a portion of the digestive tract in a human body with an endoscope inserted through the mouth, esophagus and stomach to the pylorus.

0011<figref idref="DRAWINGS">FIG. 3A</figref> is a drawing of an over-the-wire sizing balloon that may be used to dilate and measure (size) the intestinal tract and pylorus anatomy.

0012<figref idref="DRAWINGS">FIG. 3B</figref> is a drawing of a rapid exchange or monorail sizing balloon that may be used to dilate and measure (size) the intestinal tract and pylorus anatomy.

0013<figref idref="DRAWINGS">FIG. 4</figref> is a cross-sectional view of a portion of the digestive tract in a human body. An endoscope is inserted through the mouth, esophagus and stomach to the pylorus. An over-the-wire sizing balloon is inserted through the working channel of the endoscope over a guidewire and is advanced across the pyloric opening. The balloon is inflated with saline or contrast media to a low pressure to open the pylorus and duodenum and allow measurement of the lumen diameter of the pyloric antrum, pylorus and duodenal bulb.

0014<figref idref="DRAWINGS">FIG. 5</figref> is a cross-sectional drawing of the pyloric antrum, pylorus, duodenal bulb and duodenum. An expandable anchor and intestinal bypass sleeve is implanted into the pylorus.

0015<figref idref="DRAWINGS">FIG. 6</figref> is a drawing of an expandable anchor according to exemplary embodiments of the invention.

0016<figref idref="DRAWINGS">FIG. 7</figref> is a drawing of a flat representation of the circumference of the expandable anchor disclosed in <figref idref="DRAWINGS">FIG. 2</figref>. The anchor can be laser cut from round tubing or a flat sheet of Nitinol.

0017<figref idref="DRAWINGS">FIG. 8</figref> is a drawing of a flat representation of the circumference of the expandable anchor disclosed in <figref idref="DRAWINGS">FIG. 2</figref>. The expandable anchor can be laser cut from round tubing or flat sheet of Nitinol. The individual spring arm elements of the anchor are cut at a bias angle to the longitudinal axis.

0018<figref idref="DRAWINGS">FIG. 9</figref> is a drawing of exemplary heat set mandrels for forming the shape of the anchor from the laser cut shape of <figref idref="DRAWINGS">FIG. 7</figref> and <figref idref="DRAWINGS">FIG. 8</figref> to the final shape of the anchor in <figref idref="DRAWINGS">FIG. 4</figref>.

0019<figref idref="DRAWINGS">FIG. 10</figref> is a sectional view of a delivery catheter for the expandable anchor and intestinal bypass sleeve implanted.

0020<figref idref="DRAWINGS">FIG. 11</figref> is a sectional view of an anchor and sleeve implanted into a pylorus and duodenal bulb and duodenum. The expandable anchor is covered with a membrane on both the inside and outside surfaces of the anchor to close the openings in between the spring arm elements. An intestinal bypass sleeve is attached to the expandable anchor.

0021<figref idref="DRAWINGS">FIG. 12</figref> is a sectional view of a recovery catheter for removing the expandable anchor and intestinal bypass sleeve from the human gastrointestinal tract.

0022<figref idref="DRAWINGS">FIG. 13</figref> is a sectional view of the expandable anchor in the collapsed state with the outer sheath of the recovery catheter covering and constraining the expandable anchor.

0023<figref idref="DRAWINGS">FIG. 14</figref> is a sectional view of an alternative embodiment of an anchor and sleeve implanted into the pylorus and duodenal bulb and duodenum.

0024<figref idref="DRAWINGS">FIG. 15</figref> is a sectional view of an alternative embodiment of an anchor and sleeve implanted into the pylorus and duodenal bulb and duodenum.

0025<figref idref="DRAWINGS">FIG. 16</figref> is a sectional view of an alternative embodiment of the invention herein disclosed implanted into the pylorus and duodenal bulb and duodenum. The through lumen of the expandable anchor contains a duck bill type anti-reflux valve and a flow limiter.

0026<figref idref="DRAWINGS">FIG. 17</figref> is a sectional view of an alternative embodiment of the invention herein disclosed implanted into the pylorus and duodenal bulb and duodenum. The through lumen of the expandable anchor contains a ball and cage anti-reflux valve and alternatively a bi-leaflet anti-reflux valve.

0027<figref idref="DRAWINGS">FIG. 18</figref> shows an alternative embodiment of an expandable anchor.

0028<figref idref="DRAWINGS">FIG. 19</figref> is a partial cross-sectional drawing of the pyloric antrum, pylorus, duodenal bulb and duodenum. An alternative embodiment of an expandable anchor intestinal bypass sleeve is implanted into the pyloric antrum, pylorus, duodenal bulb and duodenum.

0029<figref idref="DRAWINGS">FIG. 20</figref> shows an alternative embodiment of an expandable anchor.

0030<figref idref="DRAWINGS">FIG. 21A</figref> is a drawing of a flat representation of the expandable anchor shown in <figref idref="DRAWINGS">FIG. 20</figref>.

0031<figref idref="DRAWINGS">FIG. 21B</figref> is a drawing of a cylindrical mandrel for heat setting the expandable anchor to the hourglass shape as in <figref idref="DRAWINGS">FIG. 20</figref>.

0032<figref idref="DRAWINGS">FIG. 22</figref> shows an alternative embodiment of an expandable anchor.

0033<figref idref="DRAWINGS">FIG. 23</figref> shows an alternative embodiment of an expandable anchor.

0034<figref idref="DRAWINGS">FIG. 24</figref> is a drawing of expandable anchor of <figref idref="DRAWINGS">FIG. 23</figref> in a compressed state, with a sheath constraining it on the outside diameter.

0035<figref idref="DRAWINGS">FIG. 25</figref> shows an alternative embodiment of an expandable anchor formed from wire.

0036<figref idref="DRAWINGS">FIG. 26</figref> shows an alternative embodiment of an expandable anchor formed from wire.

0037<figref idref="DRAWINGS">FIG. 27</figref> shows an alternative embodiment of an expandable anchor formed from wire.

0038<figref idref="DRAWINGS">FIG. 28</figref> shows an alternative embodiment of an expandable anchor formed from wire.

0039<figref idref="DRAWINGS">FIG. 29</figref> shows an alternative embodiment of an expandable anchor.

0040<figref idref="DRAWINGS">FIG. 30</figref> shows an alternative embodiment of an expandable anchor.

0041<figref idref="DRAWINGS">FIG. 31</figref> is a cross-sectional view of the pyloric antrum, pylorus, duodenal bulb and the duodenum in the human body. An expandable anchor and intestinal bypass sleeve is implanted across the pylorus.

0042<figref idref="DRAWINGS">FIG. 32</figref> shows an alternative embodiment of an expandable anchor formed in the shape of a toroidal-shaped coil.

0043<figref idref="DRAWINGS">FIG. 33A</figref> is a drawing of an alternative embodiment of an expandable anchor formed in the shape of a toroidal-shaped coil. The coil may have small tissue penetrating anchors on the outer surface of the coil.

0044<figref idref="DRAWINGS">FIG. 33B</figref> is a drawing of an alternative embodiment of an expandable anchor formed in the shape of a toroidal-shaped coil. The direction of the winding of the coil is reversed to cancel out the helical twisting action of the spring.

0045<figref idref="DRAWINGS">FIG. 33C</figref> is a drawing of an alternative embodiment of an expandable anchor formed in the shape of a toroidal-shaped coil as previously disclosed. The spring is wound to have double helices that are 180 degrees offset from each other.

0046<figref idref="DRAWINGS">FIG. 34A</figref> is an alternative embodiment of a toroidal spring that is made from laser cutting a pattern into a round piece of Nitinol tubing. The Nitinol tubing is laser cut in the straight tubular shape and then the cut tube is then formed into the toroidal shape.

0047<figref idref="DRAWINGS">FIG. 34B</figref> is an alternative embodiment of a toroidal spring that is made from laser cutting a pattern into a round piece of Nitinol tubing. The Nitinol tubing is laser cut in the straight round tubular shape and then it is formed into the toroidal shape. Alternatively, the part may be cut from a flat sheet of Nitinol and then shape set into the final shape.

0048<figref idref="DRAWINGS">FIG. 35</figref> is a drawing of an alternative embodiment of an expandable anchor. The drawing shows additional embodiments for the expandable anchors in <figref idref="DRAWINGS">FIG. 32</figref>, <figref idref="DRAWINGS">FIG. 33</figref> and <figref idref="DRAWINGS">FIG. 34</figref>.

0049<figref idref="DRAWINGS">FIG. 36</figref> is an assembly drawing with the expandable anchors in <figref idref="DRAWINGS">FIG. 32</figref>, <figref idref="DRAWINGS">FIG. 33</figref>, <figref idref="DRAWINGS">FIG. 34</figref> and

0050<figref idref="DRAWINGS">FIG. 37</figref> is a drawing showing an assembly drawing of a fixed diameter cylinder for the central pyloric portion of the invention herein disclosed.

0051<figref idref="DRAWINGS">FIG. 38</figref> is drawing showing of a central pyloric portion of the invention herein disclosed in which the mid portion allows for opening and closing of the pylorus, while there is a first and a second ring which are fixed rigidly together. The expandable anchors in the pyloric antrum and the duodenal bulb are tethered to the first and second rings.

0052<figref idref="DRAWINGS">FIG. 39</figref> is a sectional view of the invention herein disclosed implanted into the pyloric antrum, pylorus and duodenal bulb and duodenum. The anchoring device is comprised of two disk-shaped expandable anchors that are connected to a central cylinder which has a thin-walled compliant membrane over the central portion to allow opening and closing of the pyloric aperture.

0053<figref idref="DRAWINGS">FIG. 40</figref> is a sectional view of the invention herein disclosed implanted into the pyloric antrum, pylorus and duodenal bulb and duodenum. The anchoring device is comprised of two disk-shaped expandable anchors that are connected to a central cylinder. The lumen of the anchoring device has a one-way anti-reflux valve and a flow limiter.

0054<figref idref="DRAWINGS">FIG. 41</figref> is a sectional view of the invention herein disclosed implanted into the pyloric antrum, pylorus and duodenal bulb and duodenum. The anchoring device is comprised of two disk-shaped expandable anchors that are connected to a central cylinder. The diameter of the central cylinder is elastic and the diameter can be compressed to allow a reduced diameter of the anchor to allow the anchor to be loaded onto a smaller diameter catheter than with a fixed diameter central cylinder.

0055<figref idref="DRAWINGS">FIG. 42</figref> is a sectional view of the invention herein disclosed implanted into the pyloric antrum, pylorus and duodenal bulb and duodenum. The anchoring device is comprised of two disk-shaped expandable anchors that are connected by a thin-walled tubular membrane. The thin-walled tubular membrane allows normal pylorus opening and closing.

0056<figref idref="DRAWINGS">FIG. 43</figref> is a sectional view of the invention herein disclosed implanted into the duodenal bulb and duodenum. The anchoring device is comprised of two disk-shaped expandable anchors that are connected to a central cylinder. The lumen of the anchoring device has an optional one-way anti-reflux valve and an optional flow limiter. The anti-reflux valve and flow-limiter can be used together in combination or separately on the device.

0057<figref idref="DRAWINGS">FIG. 44</figref> is a sectional view of the invention herein disclosed. The anchoring device is comprised of two disk-shaped expandable anchors that are connected to a central cylinder. The anchoring device is implanted into the pyloric antrum and the intestinal bypass sleeve is implanted from the pyloric antrum to the duodenum.

0058<figref idref="DRAWINGS">FIG. 45A</figref> is a sectional view of the invention herein disclosed. The anchoring device is comprised of two disk-shaped expandable anchors that are connected to a central cylinder. Four additional expandable anchors are attached to the thin-walled sleeve and are implanted into the pyloric antrum.

0059<figref idref="DRAWINGS">FIG. 45B</figref> is a drawing of a flat braided wire form that may be used as an expandable anchor.

0060<figref idref="DRAWINGS">FIG. 46</figref> is a drawing of an alternative embodiment of the invention herein disclosed. The expandable anchor is comprised of a hollow tubular braided structure of wire. The wire form has been shaped to conform to the shape of the pylorus and the duodenal bulb.

0061<figref idref="DRAWINGS">FIG. 47</figref> is a drawing of an alternative embodiment of the invention herein disclosed. The expandable anchor is comprised of hollow tubular braided structure of wire. The wire form has been shaped to conform to the shape of the pylorus and the duodenal bulb. The expandable anchor and the intestinal bypass sleeve have been implanted into a human pylorus and duodenal bulb.

0062<figref idref="DRAWINGS">FIG. 48</figref> is a drawing of an alternative embodiment of the invention herein disclosed. The expandable anchor is comprised of a hollow tubular braided structure of wire. The wire form has been shaped to conform to the shape of the pylorus and the duodenal bulb. The expandable anchor has an annular groove formed in wall the duodenal bulb portion of the expandable anchor. The annular groove is sized to provide for a modular connection means between an expandable anchor and intestinal bypass sleeve.

0063<figref idref="DRAWINGS">FIG. 49</figref> is a drawing of an alternative embodiment of the invention herein disclosed implanted into a pyloric antrum, pylorus, duodenal bulb, and duodenum. The expandable anchor is comprised of a hollow tubular braided structure of wire. The wire form has been shaped to conform to the shape of the pylorus and the duodenal bulb. The expandable anchor has an annular grove formed in wall the duodenal bulb portion of the expandable anchor. The annular groove is sized to provide for a modular connection means between an expandable anchor and intestinal bypass sleeve. An intestinal bypass sleeve with an expandable anchor attached to the end of the sleeve is attached to the annular groove in the anchor in the pylorus.

0064<figref idref="DRAWINGS">FIG. 50</figref> is a drawing showing the process steps for the manufacturing of the expandable anchor as in <figref idref="DRAWINGS">FIG. 46</figref>, <figref idref="DRAWINGS">FIG. 47</figref> and <figref idref="DRAWINGS">FIG. 48</figref>.

0065<figref idref="DRAWINGS">FIG. 51</figref> is drawing of an alternative embodiment of the expandable anchor herein disclosed.

0066<figref idref="DRAWINGS">FIG. 52A</figref> is a drawing of a pyloric antrum, pylorus, duodenal bulb and duodenum and of the expandable anchor of <figref idref="DRAWINGS">FIG. 52</figref>.

0067<figref idref="DRAWINGS">FIG. 52B</figref> is a drawing of a pylorus and of the expandable anchor of <figref idref="DRAWINGS">FIG. 52</figref> implanted into it.

0068<figref idref="DRAWINGS">FIG. 53</figref> is drawing of an alternative embodiment of the expandable anchor herein disclosed.

0069<figref idref="DRAWINGS">FIG. 54</figref> is a drawing of an alternative embodiment of an expandable anchor that has optional barbs to provide for an additional securing means to the pylorus.

0070<figref idref="DRAWINGS">FIG. 55</figref> is a sectional view of the invention herein disclosed implanted into the pyloric antrum, pylorus and duodenal bulb and duodenum. The anchoring device is comprised of two disk-shaped expandable anchors that are connected to a central cylinder. The diameter of the central cylinder is fixed, but it may also be designed to allow it to be reduced in diameter during loading of the device onto a catheter. The length of the central cylinder is adjusted to allow the spacing between the two disks to be variable in spacing.

0071<figref idref="DRAWINGS">FIG. 56</figref> is a sectional view of the invention herein disclosed implanted into the pyloric antrum, pylorus and duodenal bulb and duodenum. The anchoring device is comprised of two toroidal-shaped expandable anchors that are connected to a central cylinder. The diameter of the central cylinder is fixed, but it may also be elastic to allow it to be reduced in diameter during loading of the device onto a catheter. An optional needle, suture, T-bar, hollow helical anchor or screw type anchor is inserted into and or through the tissue of the pylorus, pyloric antrum or duodenum to provide additional anchoring and securement of the intestinal bypass sleeve anchoring device to the pylorus anatomy. Additional anchoring means may include a T-Bar and suture.

0072<figref idref="DRAWINGS">FIG. 57</figref> is a sectional view of the invention herein disclosed implanted into a pylorus, duodenal bulb and duodenum. An expandable ring is sized large enough in diameter to engage the wall of the stomach pyloric antrum. The central portion of the device is constructed of a ridged fixed diameter cylinder, or alternatively a compressible cylinder or a thin-walled sleeve. An optional needle, suture, T-bar, hollow helical anchor or screw-type anchor is inserted into and or through the tissue of the pylorus, pyloric antrum or duodenum to provide additional anchoring and securement of the intestinal bypass sleeve anchoring device to pylorus anatomy or other suitable location.

0073<figref idref="DRAWINGS">FIG. 58</figref> is a cross-sectional view of a portion of the digestive tract in a human body. An intestinal bypass sleeve is implanted in the duodenum from the pylorus to the ligament of treitz. The sleeve is held in place at the pylorus by an expandable anchor that anchors on the pylorus optional secondary expandable anchors anchor the sleeve at additional locations in the duodenum and jejunum. An expandable anchor with an anti-reflux valve is implanted at the gastroesophageal (GE) junction to help resolve gastroesophageal reflux disease (GERD).

0074<figref idref="DRAWINGS">FIG. 59A</figref> is a drawing of an alternative embodiment of an expandable anchor.

0075<figref idref="DRAWINGS">FIG. 59B</figref> is a drawing of an alternative embodiment of an expandable anchor.

0076<figref idref="DRAWINGS">FIG. 59C</figref> is a drawing of an alternative embodiment of an expandable anchor.

0077<figref idref="DRAWINGS">FIG. 60</figref> is a drawing of <figref idref="DRAWINGS">FIG. 59A</figref> implanted into a pylorus. Alternatively <figref idref="DRAWINGS">FIG. 59A</figref>, <figref idref="DRAWINGS">FIG. 59B</figref> and <figref idref="DRAWINGS">FIG. 59C</figref> could also be implanted into the pyloric antrum, duodenal bulb or duodenum or GE junction.

0078<figref idref="DRAWINGS">FIG. 61A</figref> is a drawing of an intestinal bypass sleeve.

0079<figref idref="DRAWINGS">FIG. 61B</figref> is a drawing of an alternative embodiment of an intestinal bypass sleeve.

0080<figref idref="DRAWINGS">FIG. 62A</figref> is a drawing of an alternative embodiment of an intestinal bypass sleeve.

0081<figref idref="DRAWINGS">FIG. 62B</figref> is a drawing of an alternative embodiment of an intestinal bypass sleeve.

0082<figref idref="DRAWINGS">FIG. 63A</figref> is a drawing of an alternative embodiment of an intestinal bypass sleeve.

0083<figref idref="DRAWINGS">FIG. 63B</figref> is a drawing of an alternative embodiment of an intestinal bypass sleeve.

0084<figref idref="DRAWINGS">FIG. 64A</figref> is drawing of a hemispherical-shaped covering for an expandable anchor that is assembled from a sheet of polymer material into a spherical shape.

0085<figref idref="DRAWINGS">FIG. 64B</figref> is a drawing of hemispherical-shaped covering for an expandable anchor that is made by radial stretching a tube perform into a spherical shape by blow-molding or mechanical stretching.

0086<figref idref="DRAWINGS">FIG. 65A</figref> is drawing of a hemispherical- or disk-shaped covering for an expandable anchor that is assembled from sheet material into a spherical or disk shape.

0087<figref idref="DRAWINGS">FIG. 65B</figref> is drawing of a disk-shaped covering for an expandable anchor that is assembled from sheet material into a disk shape.

0088<figref idref="DRAWINGS">FIG. 65C</figref> is drawing of a hemispherical- or disk-shaped covering for an expandable anchor that is assembled from tube and sheet material into a disk shape.

0089<figref idref="DRAWINGS">FIG. 66</figref> is a drawing of an expandable anchor that has an Archimedes screw-type pump and motor integrated into the central cylinder or thru lumen of the device. The Archimedes screw is used to control the flow rate of chyme and/or to pump chyme from the stomach into the duodenum.

0090<figref idref="DRAWINGS">FIG. 67</figref> is a sectional drawing of a part of the anatomy, a pyloric antrum, pylorus, duodenal bulb, and duodenum. The expandable anchor of <figref idref="DRAWINGS">FIG. 66</figref> is implanted into the pyloric antrum, pylorus, duodenal bulb and duodenum.

0091<figref idref="DRAWINGS">FIG. 68</figref> is a cross-sectional drawing of a portion of the digestive tract in a human body. The expandable anchor of <figref idref="DRAWINGS">FIG. 66</figref> is implanted into the pyloric antrum, pylorus, duodenal bulb and duodenum. A secondary Archimedes screw-type pump is attached to the first pump by means of a flexible drive shaft and is housed in a hollow flexible cannula that is attached to the expandable anchor.

0092<figref idref="DRAWINGS">FIG. 69A</figref> is a drawing an alternative embodiment of an expandable anchor.

0093<figref idref="DRAWINGS">FIG. 69B</figref> is a drawing of an alternative embodiment of an expandable anchor.

0094<figref idref="DRAWINGS">FIG. 70A</figref> is drawing of a piece of ePTFE tubing with an inner tube of silicone or latex inserted through the inside diameter of the ePTFE. The ePTFE tube in the final form can be use for covering an expandable anchor used to anchor an intestinal bypass sleeve. The covering for the expandable anchor and the intestinal bypass sleeve can be formed into one single unitary piece in some embodiments.

0095<figref idref="DRAWINGS">FIG. 70B</figref> is a longitudinal cross-section drawing of the ePTFE tube and silicone tube shown in <figref idref="DRAWINGS">FIG. 70A</figref>.

0096<figref idref="DRAWINGS">FIG. 70C</figref> is a drawing of a mold cavity the ePTFE tube from <figref idref="DRAWINGS">FIG. 70A</figref> and <figref idref="DRAWINGS">FIG. 70B</figref> will be radially stretched and inflated into the shape of the mold cavity. The radial expansion of the tube of ePTFE is like what was previously disclosed in <figref idref="DRAWINGS">FIG. 64B</figref>.

0097<figref idref="DRAWINGS">FIG. 71A</figref> is a drawing of a two mold cavities of <figref idref="DRAWINGS">FIG. 70C</figref> that are used together to provide an enclosed cavity to limit the expansion of the ePTFE during the blow-molding radial stretching process.

0098<figref idref="DRAWINGS">FIG. 71B</figref> is a drawing of the two mold cavities assembled one cavity half on top of the other. The ePTFE tube and latex tubing are inserted through the central bore between the two mold halves.

0099<figref idref="DRAWINGS">FIG. 72A</figref> is a drawing of the two mold halves opened after the ePTFE tube has been blow-molded to the shape of the mold cavities.

0100<figref idref="DRAWINGS">FIG. 72B</figref> is a drawing of the ePTFE tube removed from the mold cavity after the blow-molding/radial stretching process is complete.

0101<figref idref="DRAWINGS">FIG. 72C</figref> is a drawing of the cross-section of the ePTFE tube and silicone tube inflated, while the two tubes are still in the mold of <figref idref="DRAWINGS">FIG. 71B</figref>, after the pressure is released.

0102<figref idref="DRAWINGS">FIG. 73</figref> is a drawing of an alternate embodiment for a shape for the mold cavity for blow-molding the ePTFE tube.

0103<figref idref="DRAWINGS">FIG. 74</figref> is a drawing of an alternate embodiment of a shape for the mold cavity for blow-molding the ePTFE tube.

0104<figref idref="DRAWINGS">FIG. 75</figref> is a drawing of an alternate embodiment of a shape for the mold cavity for blow-molding the ePTFE tube.

0105<figref idref="DRAWINGS">FIG. 76</figref> is a drawing of an alternate embodiment of a shape for the mold cavity for blow-molding the ePTFE tube.

0106<figref idref="DRAWINGS">FIG. 77A</figref> is a drawing of the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE.

0107<figref idref="DRAWINGS">FIG. 77B</figref> is a drawing of an alternative embodiment the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE.

0108<figref idref="DRAWINGS">FIG. 77C</figref> is a drawing of an alternative embodiment the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE.

0109<figref idref="DRAWINGS">FIG. 77D</figref> is a drawing of an alternative embodiment the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE.

0110<figref idref="DRAWINGS">FIG. 77E</figref> is a drawing of an alternative embodiment the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE.

0111<figref idref="DRAWINGS">FIG. 78A</figref> is a drawing of the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The anchor covering portion of the sleeve and the intestinal bypass sleeve are formed integrally into one sleeve.

0112<figref idref="DRAWINGS">FIG. 78B</figref> is a drawing of the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The anchor covering portion of the sleeve and the intestinal bypass sleeve are formed integrally into one sleeve. The small-diameter end of the tube is started to be inverted inside to pull it inside to form an interior tube layer for the expandable anchor.

0113<figref idref="DRAWINGS">FIG. 78C</figref> is a drawing of the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The anchor covering portion of the sleeve and the intestinal bypass sleeve are formed integrally into one sleeve. The small-diameter end of the tube is fully inverted inside forming an interior layer for the expandable anchor.

0114<figref idref="DRAWINGS">FIG. 79A</figref> is a drawing of an alternative embodiment of the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The anchor covering portion of the sleeve and the intestinal bypass sleeve are formed integrally into one sleeve.

0115<figref idref="DRAWINGS">FIG. 79B</figref> is a drawing of an alternative embodiment of the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The anchor covering portion of the sleeve and the intestinal bypass sleeve are formed integrally into one sleeve. The small diameter end of the tube is started to be inverted inside to pull it inside to form an interior tube layer for the expandable anchor.

0116<figref idref="DRAWINGS">FIG. 79C</figref> is a drawing of an alternative embodiment of the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The anchor covering portion of the sleeve and the intestinal bypass sleeve are formed integrally into one sleeve. The small diameter end of the tube is fully inverted inside forming an interior layer for the expandable anchor.

0117<figref idref="DRAWINGS">FIG. 80A</figref> is a drawing of an alternative embodiment of the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The anchor covering portion of the sleeve and the intestinal bypass sleeve are formed integrally into one sleeve.

0118<figref idref="DRAWINGS">FIG. 80B</figref> is a drawing of an alternative embodiment of the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The anchor covering portion of the sleeve and the intestinal bypass sleeve are formed integrally into one sleeve. The small-diameter end of the tube is started to be inverted inside to pull it inside to form an interior tube layer for the expandable anchor.

0119<figref idref="DRAWINGS">FIG. 80C</figref> is a drawing of an alternative embodiment of the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The anchor covering portion of the sleeve and the intestinal bypass sleeve are formed integrally into one sleeve. The small-diameter end of the tube is fully inverted inside forming an interior layer for the expandable anchor.

0120<figref idref="DRAWINGS">FIG. 81A</figref> is a drawing of an alternative embodiment of the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The anchor covering portion of the sleeve and the intestinal bypass sleeve are formed integrally into one sleeve.

0121<figref idref="DRAWINGS">FIG. 81B</figref> is a drawing of an alternative embodiment of the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The anchor covering portion of the sleeve and the intestinal bypass sleeve are formed integrally into one sleeve. The one end of the tube is started to be inverted inside to pull it inside to form an interior tube layer for the expandable anchor.

0122<figref idref="DRAWINGS">FIG. 81C</figref> is a drawing of an alternative embodiment of the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The anchor covering portion of the sleeve and the intestinal bypass sleeve are formed integrally into one sleeve. The one end of the tube is fully inverted inside forming an interior layer for the expandable anchor.

0123<figref idref="DRAWINGS">FIG. 82A</figref> is a drawing of an alternative embodiment of the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The anchor covering portion of the sleeve and the intestinal bypass sleeve are formed integrally into one sleeve. The small diameter end of the tube is inverted inside to pull it inside to form an interior tube layer for the expandable anchor. The interior tube is formed into the shape of anti-reflux valve.

0124<figref idref="DRAWINGS">FIG. 82B</figref> is a drawing of an alternative embodiment of the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The anchor covering portion of the sleeve and the intestinal bypass sleeve are formed integrally into one sleeve. The small diameter end of the tube is inverted inside to pull it inside to form an interior tube layer for the expandable anchor. The interior tube is formed into the shape of a restrictive stoma.

0125<figref idref="DRAWINGS">FIG. 82A</figref> is a drawing of an alternative embodiment of the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The anchor covering portion of the sleeve and the intestinal bypass sleeve are formed integrally into one sleeve. The small-diameter end of the tube is inverted inside to pull it inside to form an interior tube layer for the expandable anchor. The interior tube is formed into the shape of a restrictive stoma and then an anti-reflux valve in series.

0126<figref idref="DRAWINGS">FIG. 83A</figref> is a drawing of an alternative embodiment of the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The anchor covering portion of the sleeve and the intestinal bypass sleeve are formed integrally into one sleeve. The small-diameter end of the tube is inverted inside to pull it inside to form an interior tube layer for the expandable anchor. The interior tube is formed into the shape of a restrictive stoma and then an anti-reflux valve in series.

0127<figref idref="DRAWINGS">FIG. 83B</figref> is a drawing of an alternative embodiment of the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The anchor covering portion of the sleeve and the intestinal bypass sleeve are formed integrally into one sleeve. The small-diameter end of the tube is inverted inside to pull it inside to form an interior tube layer for the expandable anchor. The intestinal bypass sleeve has annular rings or corrugations molded into it to allow for the sleeve to bend easier without kinking and to provide for more longitudinal elasticity.

0128<figref idref="DRAWINGS">FIG. 84</figref> is a drawing of an alternative embodiment of the embodiment shown in <figref idref="DRAWINGS">FIG. 46</figref>. The expandable anchor is comprised of a hollow tubular braided structure of wire. The wire form has been shaped to conform to the shape of the pylorus and the duodenal bulb. Optional barbs and/or hooks provide for additional tissue penetration and anchoring.

0129<figref idref="DRAWINGS">FIG. 85</figref> is a drawing of an expandable anchor. The expandable anchor incorporates optional barbs and/or hooks have been incorporated into the anchor to provide for tissue penetration and additional anchoring.

0130<figref idref="DRAWINGS">FIG. 86</figref> is a drawing of an expandable anchor. The expandable anchor incorporates optional barbs and/or hooks have been incorporated into the anchor to provide for tissue penetration and additional anchoring.

0131<figref idref="DRAWINGS">FIG. 87</figref> is a drawing of an expandable anchor. The expandable anchor incorporates optional barbs and/or hooks have been incorporated into the anchor to provide for tissue penetration and additional anchoring.

0132<figref idref="DRAWINGS">FIG. 88</figref> is a drawing of an expandable anchor. The expandable anchor incorporates optional barbs and/or hooks have been incorporated into the anchor to provide for tissue penetration and additional anchoring.

0133<figref idref="DRAWINGS">FIG. 89</figref> is a drawing of an expandable anchor in which the anchors antral disk is larger in diameter than the duodenal bulb disk.

0134<figref idref="DRAWINGS">FIG. 90</figref> is a drawing of an expandable anchor.

0135<figref idref="DRAWINGS">FIGS. 91-94</figref> show various embodiments of anti-reflux valves for use in conjunction with an expandable anchor.

0136<figref idref="DRAWINGS">FIGS. 95-96</figref> show various embodiments of anti-reflux valve frames having flexing posts for use in conjunction with an expandable anchor.

DETAILED DESCRIPTION OF THE DRAWINGS

0137<figref idref="DRAWINGS">FIG. 1</figref> is a sectional view of an embodiment of the invention implanted in a portion of a human digestive tract. As a person ingests food, the food enters the mouth <b>100</b>, is chewed, and then proceeds down the esophagus <b>101</b> to the lower esophageal sphincter at the gastro-esophageal junction <b>102</b> and into the stomach <b>103</b>. The food mixes with enzymes in the mouth <b>100</b> and in the stomach <b>103</b>. The stomach <b>103</b> converts the food to a semi-fluid substance called chyme. The chyme enters the pyloric antrum <b>104</b> and exits the stomach <b>103</b> through the pylorus <b>106</b> and pyloric orifice <b>105</b>. The pylorus (or pyloric sphincter) is a band of muscle that functions to adjust the diameter of the pyloric orifice, which in turn effects the rate at which chyme exits the stomach. The pylorus (or phyloric sphincter) also has a width (or thickness), which is the distance that the pylorus extends between the stomach and the duodenum. The small intestine is about 21 feet long in adults. The small intestine is comprised of three sections: the duodenum <b>112</b>, jejunum <b>113</b> and ileum (not shown). The duodenum <b>112</b> is the first portion of the small intestine and is typically 10-12 inches long. The duodenum <b>112</b> is comprised of four sections: the superior, descending, horizontal and ascending. The duodenum <b>112</b> ends at the ligament of treitz <b>109</b>. The papilla of vater <b>108</b> is the duct that delivers bile and pancreatic enzymes to the duodenum <b>112</b>. The duodenal bulb <b>107</b> is the portion of the duodenum which is closest to the stomach <b>103</b>. As shown, an intestinal bypass sleeve <b>111</b> is implanted in the duodenum from the pyloric antrum <b>104</b> and pylorus <b>106</b> to the ligament of treitz <b>109</b>. The intestinal bypass sleeve <b>111</b> is held in place at the pylorus <b>106</b> by an expandable anchor <b>110</b> that anchors on the pylorus <b>106</b>.

0138In various exemplary embodiments, the sleeve <b>111</b> is integrally formed with or coupled to the expandable anchor <b>110</b>. According to other exemplary embodiments, the sleeve <b>111</b> is removably or releasably coupled to the expandable anchor <b>110</b>. According to various embodiments, the bypass sleeve has a diameter of between about 10 mm and about 35 mm. According to various embodiments, the bypass sleeve has a thickness of between about 0.001 and about 0.015 inches. Exemplary structures for removably or releasably coupling or attaching the sleeve <b>111</b> to the expandable anchor <b>110</b> are disclosed for example in U.S. patent application Ser. No. 12/752,697, filed Apr. 1, 2010, entitled “Modular Gastrointestinal Prostheses,” which is incorporated herein by reference. According to various embodiments, the sleeve <b>111</b> or the expandable anchor <b>110</b> (or both) are further coupled at the pylorus <b>106</b> using one or more of the techniques described in either of U.S. patent application Ser. No. 12/752,697 or U.S. patent application Ser. No. 12/833,605, filed Jul. 9, 2010, entitled “External Anchoring Configuration for Modular Gastrointestinal Prostheses,” both of which are incorporated herein by reference. According to various embodiments of the invention, the sleeve <b>111</b> may be configured and coupled to the expandable anchor <b>110</b>, using one or more of the configurations disclosed in U.S. patent application Ser. No. 12/986,268, filed Jan. 7, 2011, entitled “Gastrointestinal Prostheses Having Partial Bypass Configurations,” which is incorporated herein by reference.

0139<figref idref="DRAWINGS">FIG. 2</figref> is a sectional view of a portion of the digestive tract in a human body. As shown, an endoscope <b>114</b> has been inserted through: the mouth <b>100</b>, esophagus <b>101</b>, stomach <b>103</b> and pyloric antrum <b>104</b> to allow visualization of the pylorus <b>106</b>. Endoscopes <b>114</b> are used for diagnostic and therapeutic procedures in the gastrointestinal tract. The typical endoscope <b>114</b> is steerable by turning two rotary dials <b>115</b> to cause deflection of the working end <b>116</b> of the endoscope. The working end of the endoscope or distal end <b>116</b>, typically contains two fiber bundles for lighting <b>117</b>, a fiber bundle for imaging <b>118</b> (viewing) and a working channel <b>119</b>. The working channel <b>119</b> can also be accessed on the proximal end of the endoscope. The light fiber bundles and the image fiber bundles are plugged into a console at the plug in connector <b>120</b>. The typical endoscope has a working channel in the 2.6 to 3.2 mm diameter range. The outside diameter is typically in the 8 to 12 mm diameter range depending on whether the endoscope is for diagnostic or therapeutic purposes.

0140<figref idref="DRAWINGS">FIG. 3A</figref> is a drawing of an over-the-wire sizing balloon <b>121</b> that is used to measure the diameter of the pylorus <b>106</b>, duodenal bulb <b>107</b>, esophagus <b>102</b>, pyloric antrum <b>104</b> or other lumen in the GI tract. The sizing balloon is composed of the following elements: proximal hub <b>122</b>, catheter shaft <b>124</b>, distal balloon component <b>125</b>, radiopaque marker bands <b>126</b>, distal tip <b>127</b>, guidewire lumen <b>128</b>, inflation lumen <b>129</b>. Distal balloon component <b>125</b> can be made from silicone, silicone polyurethane copolymers, latex, nylon 12, PET (Polyethylene terephthalate) Pebax (polyether block amide), polyurethane, polyethylene, polyester elastomer or other suitable polymer. The distal balloon component <b>125</b> can be molded into a cylindrical shape, into a dogbone or a conical shape. The distal balloon component <b>125</b> can be made compliant or non-compliant. The distal balloon component <b>125</b> can be bonded to the catheter shaft <b>124</b> with glue, heat bonding, solvent bonding, laser welding or suitable means. The catheter shaft can be made from silicone, silicone polyurethane copolymers, latex, nylon 12, PET (Polyethylene terephthalate) Pebax (polyether block amide), polyurethane, polyethylene, polyester elastomer or other suitable polymer. Section A-A in <figref idref="DRAWINGS">FIG. 3A</figref> is a cross-section of the catheter shaft <b>124</b>. The catheter shaft <b>124</b> if shown as a dual lumen extrusion with a guidewire lumen <b>128</b> and an inflation lumen <b>129</b>. The catheter shaft <b>124</b> can also be formed from two coaxial single lumen round tubes in place of the dual lumen tubing. The balloon is inflated by attaching a syringe (not shown) to a luer fitting side port <b>130</b>. The sizing balloon accommodates a guidewire through the guidewire lumen from the distal tip <b>127</b> through the proximal hub <b>122</b>. The sizing balloon can be filled with saline or a radiopaque dye to allow visualization and measurement of the size of the anatomy with a fluoroscope. The sizing balloon <b>121</b> has two or more radiopaque marker bands <b>126</b> located on the catheter shaft to allow visualization of the catheter shaft and balloon position. The marker bands <b>126</b> also serve as fixed known distance reference points that can be measured to provide a means to calibrate and determine the balloon diameter with the use of the fluoroscope. The marker bands can be made from tantalum, gold, platinum, platinum iridium alloys or other suitable material.

0141<figref idref="DRAWINGS">FIG. 3B</figref> shows a rapid exchange sizing balloon <b>134</b> that is used to measure the diameter of the pylorus <b>106</b>, duodenal bulb <b>107</b>, esophagus <b>101</b>, pyloric antrum <b>104</b> or other lumen in the GI tract. The sizing balloon is composed of the following elements: proximal luer <b>131</b>, catheter shaft <b>124</b>, distal balloon component <b>125</b>, radiopaque marker bands <b>126</b>, distal tip <b>127</b>, guidewire lumen <b>128</b>, inflation lumen <b>129</b>. The materials of construction will be similar to that of <figref idref="DRAWINGS">FIG. 4A</figref>. The guidewire lumen <b>128</b> does not travel the full length of the catheter. It starts at the distal tip <b>127</b> and exits out the side of the catheter at distance shorter than the overall catheter length. The guidewire <b>132</b> is inserted into the balloon catheter to illustrate the guidewire path through the sizing balloon. The sizing balloon catheter shaft changes section along its length from a single lumen at section B-B <b>133</b> to a dual lumen at section A-A at <b>124</b>. An alternative hourglass-shaped balloon <b>590</b> can be used for sizing the pylorus anatomy without dilating the pylorus aperture.

0142<figref idref="DRAWINGS">FIG. 4</figref> is a sectional view of a portion of the digestive tract in a human body. As shown, an endoscope <b>114</b> is inserted through the mouth <b>100</b>, esophagus <b>101</b> and stomach <b>103</b> up to the pylorus <b>106</b>. An over the wire sizing balloon <b>121</b> is inserted through the working channel <b>119</b> of the endoscope <b>114</b> over a guidewire and is advanced across the pyloric opening <b>105</b>. The balloon is inflated with saline or contrast media to a low pressure to open the pylorus <b>106</b>, pyloric antrum <b>104</b> and duodenal bulb <b>107</b> and to allow measurements to be taken.

0143<figref idref="DRAWINGS">FIG. 5</figref> is a sectional view of the pyloric antrum <b>104</b>, pylorus <b>106</b>, duodenal bulb <b>107</b> and duodenum <b>112</b>. An expandable anchor <b>110</b> and intestinal bypass sleeve <b>111</b> is implanted into the pylorus <b>106</b>. The expandable anchor <b>110</b> is shown here without a covering material to allow for better visualization of the expandable anchor <b>110</b>. In various exemplary embodiments, the expandable anchor <b>110</b> is not covered, while in other exemplary embodiments, it is covered with a polymer membrane made from a material such as silicone, polyurethane, polytetrafluoroethylene, fluorinated ethylene propylene, polyethylene, expanded polytetrafluoroethylene or other suitable material. <figref idref="DRAWINGS">FIG. 11</figref>, for example, shows an embodiment of the expandable anchor <b>110</b> covered with a polymer film. The expandable anchor <b>110</b> can be made from metal or plastic. The intestinal bypass sleeve <b>111</b> can vary in length from 1-2 inches in length up to several feet. In some embodiments, the sleeve bypasses the length of the duodenum up to the ligament of treitz. While various embodiments disclosed herein describe the intestinal bypass sleeve as extending into the duodenum, in all such embodiments, it is also contemplated that the intestinal bypass sleeve has a length sufficient to allow it to extend partially or fully into the jejunum. The intestinal bypass sleeve <b>111</b> may be made from a thin-walled polymer material such as silicone, polyurethane, polytetrafluoroethylene, fluorinated ethylene propylene, polyethylene, expanded polytetrafluoroethylene (ePTFE) or other suitable material. In exemplary embodiments, the wall thickness of the intestinal bypass sleeve <b>111</b> may be in the range of 0.001 inch to 0.010 inch thick. The intestinal bypass sleeve <b>111</b> may be made by extrusion, into a tubular form or a lay flat tubing, dip coated from a liquid solution, powder coated from fine particles of polymer or paste extruded and then stretched as is the case with ePTFE. As shown in <figref idref="DRAWINGS">FIG. 5</figref>, the intestinal bypass sleeve <b>111</b> may have optional helical reinforcements <b>135</b> made from a polymer or metal applied to the outer, inner or within the wall thickness of the sleeve. The helical reinforcement can provide for additional kink resistance and prolapse resistance. The wind angle <b>136</b> of the helical reinforcement, in exemplary embodiments, has a high pitch angle (for example, 45 degrees) to allow the diameter of the intestinal bypass sleeve to compress easily. According to various embodiments, the wind angle <b>136</b> is in the 10 to 85 degrees range. The helical reinforcement may be made integral with the intestinal bypass sleeve or it may be added in a secondary process by bonding on a monofilament(s) <b>137</b> of polymer or wire to the surface of the sleeve.

0144<figref idref="DRAWINGS">FIG. 6</figref> is a drawing of an expandable anchor <b>110</b>. The expandable anchor <b>110</b> provides for an anchoring means to hold an intestinal bypass sleeve <b>111</b> within the small intestine. In exemplary embodiments, the expandable anchor <b>110</b> is designed to allow the anchor to be of a self expanding design. A self expanding anchor design can be compressed in diameter to allow the device to be compressed in diameter to be loaded onto a delivery catheter. The anchor <b>110</b> can then recover elastically to the original starting diameter, with the anchor diameter decreasing only a small amount due to non elastic recovery. The anchor <b>110</b> can also be made of a plastically deformable design and require a mechanical force applied to it in the radial or longitudinal direction to accomplish the expansion of the anchor. The mechanical force can be accomplished with an inflatable balloon type device, radially expanding the anchor <b>110</b>, or it may also be accomplished by a longitudinal compression of the anchor <b>110</b> by a screw type mechanism or cable tensioning means. As shown, the anchor <b>110</b> has a proximal portion or proximal disk <b>144</b> that is comprised of 26 spring arms.

0145As shown, the anchor <b>110</b> has a distal portion (e.g., open-ended cylindrical portion) <b>143</b> that is comprised of 26 spring arms. According to various embodiments, the anchor <b>110</b> could have from 3 to 72 spring arms for the proximal disk and the open ended cylinder.

0146According to exemplary embodiments, the expandable anchor <b>110</b> is made from a nickel titanium alloys (Nitinol). Other alternative suitable alloys for manufacturing the anchor <b>110</b> are stainless steel alloys: 304, 316L, BioDur® 108 Alloy, Pyromet Alloy® CTX-909, Pyromet® Alloy CTX-3, Pyromet® Alloy 31, Pyromet® Alloy CTX-1, 21Cr-6Ni-9Mn Stainless, 21Cr-6Ni-9Mn stainless, Pyromet Alloy 350, 18Cr-2Ni-12Mn Stainless, Custom 630 (17Cr-4Ni) Stainless, Custom 465® Stainless, Custom 455® Stainless Custom 450® Stainless, Carpenter 13-8 Stainless, Type 440C Stainless, cobalt chromium alloys—MP35N, Elgiloy, L605, Biodur® Carpenter CCM alloy, Titanium and titanium alloys, Ti-6Al-4V/ELI and Ti-6Al-7Nb, Ti-15Mo, Tantalum, Tungsten and tungsten alloys, pure platinum, platinum-iridium alloys, platinum-nickel alloys, niobium, iridium, conichrome, gold and gold alloys. The anchor <b>110</b> may also be comprised of the following absorbable metals: Pure Iron and magnesium alloys. The anchor <b>110</b> may also be comprised of the following plastics: Polyetheretherketone (PEEK), polycarbonate, polyolefins, polyethylenes, polyether block amides (PEBAX), nylon 6, 6-6, 12, Polypropylene, polyesters, polyurethanes, polytetrafluoroethylene (PTFE) Poly(phenylene sulfide) (PPS), poly(butylene terephthalate) PBT, polysulfone, polyamide, polyimide, poly(p-phenylene oxide) PPO, acrylonitrile butadiene styrene (ABS), Polystyrene, Poly(methyl methacrylate) (PMMA), Polyoxymethylene (POM), Ethylene vinyl acetate, Styrene acrylonitrile resin, Polybutylene. The anchor <b>110</b> may also be comprised of the following absorbable polymeres: Polyglycolic acid (PGA), Polylactide (PLA), Poly(ε-caprolactone), Poly(dioxanone) Poly(lactide-co-glycolide).

0147The anchor <b>110</b>, according to exemplary embodiments, is laser cut from a round tubing or from a flat sheet of Nitinol and then is rolled into a cylindrical shape after laser cutting. The flat representation of the anchor <b>110</b> is shown in <figref idref="DRAWINGS">FIG. 7</figref>. The anchor <b>110</b>, according to exemplary embodiments, is made from a Nitinol tube of about 9 mm outside diameter by a wall thickness of 0.006 inch thick. Alternatively a starting tube outside diameter can range from about 2 mm to 16 mm. An alternative construction method is to laser cut or chemical etch the pattern form a flat sheet of Nitinol with a thickness of 0.002 inch to 0.020 inch.

0148According to various embodiment, anchor <b>110</b> has an inside diameter <b>139</b> in the range of about 2 mm to 20 mm, Anchor <b>110</b> has an expanded open end <b>137</b> in the range of about 12 mm to 60 mm. Anchor <b>110</b> has a disk-shaped feature <b>144</b> that has a diameter <b>145</b> in the range of about 12 to 60 mm. Anchor <b>110</b> has a central cylinder <b>138</b> that has an outside diameter in the range of 4 to 20 mm. Anchor <b>110</b> has a flange <b>141</b> adjacent to large diameter open end that has a length of about 8 mm in length. According to various embodiments, this length <b>141</b> could range from a length of about 1 mm to 30 mm in length. Central cylinder section <b>138</b> can have a length <b>140</b> of about 1 mm to 30 mm. In various embodiments, the length of the cylinder section <b>138</b> is about equal to a width of the pylorus <b>106</b> (e.g., the phyloric sphincter). The proximal disk can have a length of 1 mm to 20 mm. The proximal disk <b>144</b> can alternatively be formed in the shape of a sphere. The central cylinder <b>138</b>, in various embodiments, is made from a material having a stiffness sufficient to resist compressive forces applied by the pylorus.

0149<figref idref="DRAWINGS">FIG. 7</figref> is a drawing of a flat representation of the circumference of the expandable anchor <b>110</b> disclosed in <figref idref="DRAWINGS">FIG. 6</figref>. The anchor <b>110</b> can be laser cut from a round tubing or flat sheet of Nitinol. In some embodiments of the anchor <b>110</b>, the edge <b>146</b> connects with edge <b>147</b> to form a round tubing.

0150<figref idref="DRAWINGS">FIG. 8</figref> is a drawing of a flat representation of the circumference of an alternative embodiment of an anchor <b>148</b> as disclosed in item <b>110</b> of <figref idref="DRAWINGS">FIG. 6</figref>. The expandable <b>148</b> anchor can be laser cut from round tubing or a flat sheet of Nitinol. The individual spring arm elements of the anchor are cut at a bias angle <b>149</b> to the longitudinal axis. The bias angle <b>149</b> can range from about 1 degree to about 45 degrees. In some embodiments of the anchor <b>148</b>, the edge <b>150</b> connects with edge <b>151</b> to form a tubing having a round cross-section.

0151<figref idref="DRAWINGS">FIG. 9</figref> is a drawing of heat set mandrels for heat setting (i.e., form the shape of) the anchor from the laser cut shape of <figref idref="DRAWINGS">FIG. 7</figref> and <figref idref="DRAWINGS">FIG. 8</figref> to the final shape of the anchor in <figref idref="DRAWINGS">FIG. 6</figref>. Female external mandrel <b>153</b> is made in two pieces in a clamshell arrangement. Internal mandrel <b>152</b> is placed within the external mandrel <b>153</b> and forms a cavity <b>154</b> in between the two mandrels and provides a means to shape set the Nitinol laser cut parts as in <figref idref="DRAWINGS">FIG. 7</figref> and <figref idref="DRAWINGS">FIG. 8</figref> into formed shape of anchor in <figref idref="DRAWINGS">FIG. 6</figref>. Laser cut part of <figref idref="DRAWINGS">FIG. 7</figref> or <figref idref="DRAWINGS">FIG. 8</figref> is placed into mold made of items <b>153</b> and <b>152</b>. Mold and anchor is placed in an oven or salt bath at a temperature in the range of 400 to 500 degrees centigrade and held for 10 minutes. The mold and anchor is then rapidly cooled by air or a water bath. An alternative method to heat set the anchor uses a male only mandrel <b>155</b>. The laser cut part is longitudinally compressed and clamped on the mandrel <b>155</b> to form the shape of the proximal disk.

0152<figref idref="DRAWINGS">FIG. 10</figref> is a cross-sectional drawing of a delivery catheter for the invention herein disclosed. The delivery catheter is composed of the three coaxial components: distal outer sheath <b>170</b>, which transitions down to a smaller diameter at the proximal outer sheath <b>182</b>, proximal pusher catheter <b>171</b>, and sleeve advancement pusher <b>172</b>. There are three handles on the catheter: outer sheath handle <b>173</b>, proximal pusher handle <b>174</b>, and sleeve advancement pusher handle <b>175</b>. The implant pusher <b>178</b> serves as a mechanical stop or means to hold stationery or push out the anchor rings <b>179</b> or implant from the inside of the distal outer sheath <b>170</b>. The distal tip <b>176</b> provides for a flexible tip that will track over a guidewire. The guidewire may be inserted through the central lumen <b>177</b>. The proximal shoulder of the tip <b>181</b> is rolled back over the end of the intestinal bypass sleeve <b>180</b> to constrain the intestinal bypass sleeve <b>180</b> to distal tip <b>176</b> and the sleeve advancement pusher <b>172</b> and to provide a mechanism of advancement of the intestinal bypass sleeve through the duodenum (and the jejunum as applicable). Expandable anchor <b>179</b> and the intestinal bypass sleeve <b>180</b> are compressed and loaded onto the delivery catheter.

0153The distal outer sheath <b>170</b> may be made from a plastic polymer such as Pebax (polyether block amide), hytrel (polyester elastomer), nylon 12, nylon 11, nylon 6, nylon 6,6, polyethylene, polyurethane or other suitable polymer. The distal outer sheath <b>170</b> may have an inner lining made from a polymer with a low coefficient of friction such as PTFE. The distal outer sheath <b>170</b> may also have a metal re-enforcement in the wall thickness to improve the kink resistance or burst properties of the outer sheath. The metal re-enforcement may be comprised of a braided wire mesh or a coil in the wall thickness. The metal used for the braid may be stainless steel, Nitinol, MP35N, L605, Elgiloy or other suitable material. The distal outer sheath <b>170</b> may be from 1-2 inches long up to full length of the catheter.

0154The proximal outer sheath <b>182</b> may be made from a plastic polymer such as Pebax (polyether block amide), Hytrel (polyester elastomer), nylon 12, nylon 11, nylon 6, nylon 6,6, polyethylene, polyurethane or other suitable polymer. The proximal outer sheath <b>182</b> may have an inner lining made from a polymer with a low coefficient of friction such as PTFE. The proximal outer sheath <b>182</b> may also have a metal re-enforcement in the wall thickness to improve the kink resistance or burst properties of the outer sheath. The metal re-enforcement may be comprised of a braided wire mesh or a coil in the wall thickness. The metal used for the braid may be stainless steel, Nitinol, MP35N, L605, Elgiloy or other suitable material.

0155The proximal pusher catheter <b>171</b> may be made from a plastic polymer such as Pebax (polyether block amide), Peek, Hytrel (polyester elastomer), nylon 12, nylon 11, nylon 6, nylon 6,6, polyethylene, polyurethane or other suitable polymer. The proximal pusher catheter <b>171</b> may have an inner lining made from a polymer with a low coefficient of friction such as PTFE. The proximal pusher catheter <b>171</b> may also have a metal re-enforcement in the wall thickness to improve the kink resistance or burst properties of the outer sheath. The metal re-enforcement may be comprised of a braided wire mesh or a coil in the wall thickness. The metal used for the braid may be stainless steel, Nitinol, MP35N, L605, Elgiloy or other suitable material

0156The sleeve advancement pusher <b>172</b> may be made from a plastic polymer such as Pebax (polyether block amide), Peek, Hytrel (polyester elastomer), nylon 12, nylon 11, nylon 6, nylon 6,6, polyethylene, polyurethane or other suitable polymer. The sleeve advancement pusher <b>172</b> may have an inner lining made from a polymer with a low coefficient of friction such as PTFE. The sleeve advancement pusher <b>172</b> may also have a metal re-enforcement in the wall thickness to improve the kink resistance or burst properties of the outer sheath. The metal re-enforcement may be comprised of a braided wire mesh or a coil in the wall thickness. The metal used for the braid may be stainless steel, Nitinol, MP35N, L605, Elgiloy or other suitable material. The sleeve advanced pusher <b>172</b> may have a hollow core to allow passage over a guidewire or it may be solid without an opening. The sleeve advanced pusher <b>172</b> may also be constructed of a simple tightly wound metal wire coil construction or it may be wound from multiple wires such as Hollow Helical Strand tube made be Fort Wayne Metals. The sleeve advancement pusher handle <b>175</b> may also be comprised of a solid tube of Peek, Nitinol or stainless steel. The solid tube may have a series of slots or a patterned on a portion of the tube length to increase the flexibility of the component as required.

0157The distal tip <b>176</b> may be molded from Pebax, polyurethane, Hytrel or other suitable elastomer. The distal tip <b>176</b> had an outer flange <b>181</b> that is soft and may rolled back and the intestinal bypass sleeve <b>180</b> inserted under it to secure the sleeve during transport to the distal duodenum (and the jejunum as applicable).

0158The delivery catheter handles may be molded or machined from metal or plastic. The outer sheath handle <b>173</b> is attached to the proximal outer sheath <b>182</b>. The outer sheath handle <b>173</b> is used to hold or retract the distal outer sheath <b>170</b> and the proximal outer sheath <b>182</b> during the advancement of the delivery catheter into the human anatomy, and while deploying of the anchoring rings. The proximal pusher handle <b>174</b> is attached to the proximal pusher catheter <b>171</b>. The outer sheath handle <b>173</b> is used to hold or push forward the proximal pusher catheter <b>171</b> and the implant pusher <b>178</b> during the advancement of the delivery catheter into the human anatomy, and while deploying of the anchoring rings.

0159An exemplary deployment sequence consists of the following: The delivery catheter of <figref idref="DRAWINGS">FIG. 10</figref> is preloaded with the expandable anchor <b>179</b> and the intestinal bypass sleeve <b>180</b>. The delivery catheter is advanced through the mouth <b>100</b>, esophagus <b>101</b> and stomach <b>103</b> to the pylorus <b>106</b>. The sleeve advancement pusher handle <b>175</b> is pushed distally while holding the rest of the catheter stationary. This pushes the sleeve advancement pusher handle <b>175</b>, the distal tip <b>176</b> and the intestinal bypass sleeve <b>180</b> into the duodenum (and jejunum as applicable). The pusher handle <b>175</b> is further advanced until the intestinal bypass sleeve <b>180</b> reaches the ligament of treiz. At this point all the slack in the sleeve <b>180</b> is taken up and the sleeve pulls out from the distal tip <b>176</b> and is released from the distal tip <b>176</b>.

0160<figref idref="DRAWINGS">FIG. 11</figref> is a sectional view of the invention herein disclosed implanted into a pylorus <b>106</b>, duodenal bulb <b>107</b> and duodenum <b>112</b>. The expandable anchor <b>110</b> is covered with a membrane <b>186</b>, <b>185</b> on both inside and outside surfaces of the anchor <b>110</b> to close the openings between the spring arm elements <b>187</b>. An intestinal bypass sleeve <b>111</b> is attached to the expandable anchor <b>110</b>. The membrane covering the expandable anchor may be made from a thin-walled polymer material such as silicone, polyurethane, polytetrafluoroethylene, fluorinated ethylene propylene, polyethylene, expanded polytetrafluoroethylene (ePTFE) or other suitable material. In exemplary embodiments, the wall thickness of the membrane covering the expandable anchor may be in the range of 0.001 inch to 0.030 inch thick. The membrane may be made by extrusion, dip coating from a liquid solution, powder coated from fine particles of polymer, or paste extruded and then stretched (e.g., as is typically done with ePTFE). The expandable anchor <b>110</b> membrane <b>185</b>, <b>186</b> may also be cut from a flat sheet of material such as ePTFE and then bonded or sewn into a disk shape or spherical shaped structure and then attached the expandable anchor <b>110</b> frame work by sewing or gluing with a polymer such as FEP. The expandable anchor <b>110</b> has a recovery ring <b>188</b> attached to the proximal disk to provide for a location to grab the device for removal from the human body. Expandable anchor <b>110</b> has a central tube <b>194</b> bonded at location <b>195</b>, but is free to telescope at location <b>196</b> as the anchor <b>110</b> is compressed in diameter and elongated in length to allow loading onto a delivery catheter. The central tube <b>194</b> may be made from a thin-walled metal material such as stainless steel, titanium or polymer material such as silicone, polyurethane, polytetrafluoroethylene, fluorinated ethylene propylene, polyethylene, expanded polytetrafluoroethylene (ePTFE) or other suitable material.

0161<figref idref="DRAWINGS">FIG. 12</figref> is a sectional view of recovery catheter <b>197</b> for removing the expandable anchor <b>110</b> and intestinal bypass sleeve <b>111</b> from the human gastrointestinal tract. Recovery catheter has an outer sheath <b>189</b>, an inner sheath <b>190</b>, grasper forceps <b>191</b>, central obturator <b>192</b>, and a guidewire lumen <b>193</b>. To remove the expandable anchor <b>110</b> and the intestinal bypass sleeve <b>111</b>, the recovery catheter <b>197</b>, with a guidewire inserted through the central obturator <b>192</b>, is advanced through the mouth <b>100</b>, esophagus <b>101</b>, stomach <b>103</b>, pyloric antrum <b>104</b> up to the pylorus <b>106</b>. The obturator <b>192</b> is inserted into the central lumen of the recovery ring <b>188</b>. The outer sheath <b>189</b> is pulled back to expose and allow the grasper forceps <b>191</b> to open. Grasper forceps <b>191</b> is pushed forward over the recovery ring <b>188</b> and the outer sheath <b>189</b> is the advanced to collapse grasper forceps <b>191</b>. The central obturator <b>192</b> and grasper forceps <b>191</b> is then pulled into the outer sheath <b>189</b> by retraction of the inner sheath <b>190</b>. The expandable anchor <b>110</b> is then fully collapsed and removed by retraction of the anchor <b>110</b> fully into the outer sheath <b>189</b>. FIG. <b>13</b> is a sectional view of the expandable anchor <b>110</b> in the collapsed state within the outer sheath <b>189</b> of the recovery catheter covering and constraining the expandable anchor <b>110</b>.

0162<figref idref="DRAWINGS">FIG. 14</figref> is a sectional view of an alternative embodiment of the invention herein disclosed implanted into a pylorus <b>106</b>, duodenal bulb <b>107</b> and duodenum <b>112</b>. The expandable anchor <b>110</b> is covered with a membrane on both the inside <b>186</b> and outside <b>185</b> surfaces of the anchor <b>110</b> to close the openings in between the spring arm elements <b>187</b>. An intestinal bypass sleeve <b>111</b> is attached to the expandable anchor <b>110</b>. The membrane covering the expandable anchor may be made from a thin-walled polymer material such as silicone, polyurethane, polytetrafluoroethylene, fluorinated ethylene propylene, polyethylene, expanded polytetrafluoroethylene (ePTFE) or other suitable material. In some embodiments, the wall thickness of the membrane covering the expandable anchor <b>186</b> and <b>185</b> may be in the range of 0.001 inch to 0.030 inch thick. The membrane <b>186</b> and <b>185</b> may be made by extrusion, dip coating from a liquid solution. Powder coated from fine particles of polymer or paste extruded and then stretched as is the case with ePTFE. The expandable anchor <b>110</b> membrane <b>185</b>, <b>186</b> may also be cut from a flat sheet of material such as ePTFE and then bonded or sewn into a disk-shaped or spherical-shaped structure and then attached to the expandable anchor <b>110</b> framework by sewing or gluing with a polymer such as FEP. The expandable anchor <b>110</b> has a recovery ring <b>188</b> attached to the proximal disk to provide for a location to grab the device for removal from the human body. Expandable anchor <b>110</b> has a central tube <b>199</b>, which may be bonded at locations <b>195</b> and/or <b>200</b>. The central tube <b>199</b> is comprised of an elastomeric material and can elongate in length as the anchor <b>110</b> is compressed in diameter and elongated in length to allow loading onto a delivery catheter. The central tube <b>199</b> may be made from a thin-walled polymer material such as silicone, polyurethane, polytetrafluoroethylene, fluorinated ethylene propylene, polyethylene, expanded polytetrafluoroethylene (ePTFE) or other suitable material.

0163<figref idref="DRAWINGS">FIG. 15</figref> is a sectional view of the invention herein disclosed implanted into a pylorus <b>106</b>, duodenal bulb <b>107</b> and duodenum <b>112</b>. The expandable anchor <b>110</b> is covered with a membrane on the outside <b>185</b> surface of the anchor <b>110</b> to close the openings in between the spring arm elements <b>187</b>. An intestinal bypass sleeve <b>111</b> is tapered in diameter and attaches to the expandable anchor <b>110</b> at location <b>195</b>. Intestinal bypass sleeve <b>111</b> is sized to fit the duodenum in the duodenal portion and is tapered <b>201</b> from the larger diameter to the smaller diameter at <b>196</b>. Intestinal bypass sleeve <b>111</b> is not attached to the expandable anchor at <b>196</b>, but is allowed to slide and telescope within the expandable anchor as it is compressed in diameter to load the anchor onto a delivery catheter. The membrane covering the expandable anchor <b>185</b> may be made from a thin-walled polymer material such as silicone, polyurethane, polytetrafluoroethylene, fluorinated ethylene propylene, polyethylene, expanded polytetrafluoroethylene (ePTFE) or other suitable material. In some embodiments, the wall thickness of the membrane covering the expandable anchor <b>185</b> may be in the range of 0.001 inch to 0.030 inch thick. The membrane <b>185</b> may be made by extrusion, dip coating from a liquid solution, powder coated from fine particles of polymer or paste extruded and then stretched as is the case with ePTFE. The expandable anchor <b>110</b> membrane <b>185</b> may also be cut from a flat sheet of material such as ePTFE and then bonded or sewn into a disk shape or spherical shaped structure and then attached to the expandable anchor <b>110</b> frame work by sewing or gluing with a polymer such as FEP. The expandable anchor <b>110</b> has a recovery ring <b>188</b> attached to the proximal disk to provide for a location to grab the device for removal from the human body.

0164<figref idref="DRAWINGS">FIG. 16</figref> is a cross-sectional drawing of the invention herein disclosed implanted into a pylorus <b>106</b>, duodenal bulb <b>107</b> and duodenum <b>112</b>. The rings are sized large enough in diameter that there is a contact force between the ring diameter and the stomach pyloric antrum <b>104</b> and the duodenal bulb <b>107</b>. The expandable anchor <b>110</b> is larger in diameter than the maximum opened diameter of the pylorus and therefore provides an anchoring means to hold the intestinal bypass sleeve <b>111</b>. The intestinal bypass sleeve <b>111</b> can vary in length from 1-2 inches in length up to several feet. In some embodiments, the sleeve bypasses the length of the duodenum <b>112</b> up to the ligament of treitz <b>109</b>. The intestinal bypass sleeve <b>111</b> can also be longer and bypass into the jejunum. The central tube <b>194</b> can be made from a rigid cylinder made from plastic material such as delrin, peek, high density polyethylene, polycarbonate or other suitable polymer. The central tube <b>194</b> may also be made from stainless steel, titanium or Nitinol. The fixed diameter of the central tube <b>194</b> of the device can be sized to provide for a full opening of the pylorus and not allow the pylorus to close normally. In various embodiments, the diameter of the central tube <b>194</b> ranges from as small as 3 mm in diameter up to as large as 14 mm in diameter. The central lumen of device has a one-way anti-reflux valve <b>202</b>. The anti-reflux valve <b>202</b> allows for unobstructed flow in the direction from the stomach antrum <b>104</b> to the pylorus <b>106</b>, but limits flow in the reverse direction. The anti-reflux valve <b>202</b> can be constructed of a duck bill design with two flexible leaflets <b>203</b>, or may utilize other designs such as a tri leaflet valve <b>204</b> or quad leaflet valve <b>205</b>. The anti-reflux valve may be constructed of silicone or polyurethane, polyethylene, ePTFE or other suitable polymer. In various embodiments, the anti-reflux valve functions to close an end of the bypass sleeve <b>111</b>.

0165The central cylinder <b>194</b> may also be constructed to have a flow limiter <b>206</b>. Flow limiter <b>206</b> is an orifice that can be added to limit the maximum flow rate of chyme through the central cylinder <b>202</b>. Inflatable flow limiter <b>207</b> may also be added to the central cylinder <b>194</b> to provide for an adjustable means to change the orifice size. Cylindrical hollow balloon <b>208</b> on the inside of the central cylinder <b>194</b> can be inflated with air <b>209</b>, saline or a cross-linkable polymer such as silicone to reduce the orifice size. Alternatively the central cylinder <b>194</b> may also designed to have an optional removable fixed orifice <b>210</b>. Fixed orifice <b>210</b> may be inserted before the device is implanted in a human or it can be added or size changed at a later date in the future if it is so desirable. Fixed orifice <b>210</b> can be held into central cylinder <b>194</b> by a magnetic attraction means, snap fit or mechanical interlock feature. A mechanical stop <b>211</b> can limit how far the fixed orifice <b>210</b> inserts into the central cylinder <b>194</b>. An alternative embodiment of a flow limiter may also include a compressible mechanical cage structure <b>213</b>. The cage structure <b>213</b> has a thin tubular membrane <b>214</b> on the inside. The inside diameter of cage structure <b>213</b> can be reduced to <b>212</b> by axial compression of the length of the cage structure <b>213</b>, by screwing in collar <b>215</b> into inside diameter of central cylinder <b>194</b>. An additional alternative embodiment of a flow limiter can be configured to include an obstruction device <b>216</b> that is adjustable in position to change the gap <b>217</b> to effectively provide for an adjustable flow limiter. Adjustable flow limiter <b>216</b> or <b>208</b> may be driven by a motorized method and be adjusted remotely from outside of the patient at a later time by telemetry or magnetic induction.

0166<figref idref="DRAWINGS">FIG. 17</figref> is an alternative embodiment of <figref idref="DRAWINGS">FIG. 16</figref>, wherein the anti-reflux valve is constructed of a ball <b>218</b> and cage <b>219</b> design. When the ball <b>218</b> is all the way towards the cage <b>219</b> the valve is all the way open and allows flow of chyme from the pyloric antrum <b>104</b> to duodenum <b>112</b>. When the ball <b>218</b> is up against the valve seat <b>220</b> it is closed and the retrograde flow from the duodenum <b>112</b> to the stomach <b>103</b> should be minimized. The ball <b>218</b> and cage <b>219</b> may be constructed of metal or plastics. A bi-leaflet <b>221</b> valve may also be suitable for the reflux valve. The leaflets are in an open position <b>223</b> and a closed position <b>222</b>. <figref idref="DRAWINGS">FIG. 18</figref> is a drawing of an alternative embodiment of an expandable anchor <b>224</b>. Expandable anchor <b>224</b> is comprised of a proximal expandable disk <b>225</b>, a distal expandable disk <b>226</b>, a central cylinder <b>227</b> and spring arms <b>228</b>. The function and materials are similar to the anchor disclosed in <figref idref="DRAWINGS">FIG. 6</figref>. According to various embodiments, the spring arms of the expandable disks extend away from the longitudinal axis at an angle of between about 45 and about 135 degrees.

0167<figref idref="DRAWINGS">FIG. 19</figref> is a cross-sectional drawing of expandable anchor disclosed in <figref idref="DRAWINGS">FIG. 18</figref> and an intestinal bypass sleeve implanted into a pyloric antrum <b>104</b>, pylorus <b>106</b> and duodenal bulb <b>107</b> and duodenum <b>112</b>. As shown in <figref idref="DRAWINGS">FIG. 19</figref>, the disks <b>225</b> and <b>226</b> extend radially outward at an angle of between about 10 and about 30 degrees from perpendicular.

0168<figref idref="DRAWINGS">FIG. 20</figref> is a drawing of an alternative embodiment of an expandable anchor <b>229</b>. Expandable anchor <b>229</b> is comprised of a proximal expandable cylinder <b>230</b>, a distal expandable cylinder <b>231</b>, a central cylinder <b>232</b> and spring arms <b>233</b>. The function and materials are similar to the anchor disclosed in <figref idref="DRAWINGS">FIG. 6</figref>. According to various embodiments, the proximal cylinder <b>230</b> further includes a wire, suture, or drawstring <b>283</b>. The drawstring <b>283</b> may be used to facilitate collapse and removal of the expandable anchor <b>229</b> from the patient. <figref idref="DRAWINGS">FIG. 21A</figref> is a drawing of a flat representation of the expandable anchor shown in <figref idref="DRAWINGS">FIG. 20</figref>. Cell geometry is shown in the expanded state <b>234</b> and in the compressed state <b>235</b>. <figref idref="DRAWINGS">FIG. 21B</figref> shows embodiments of cylindrical mandrels <b>236</b>A, <b>236</b>B for heat setting the expandable anchor to the hour glass shape as in <figref idref="DRAWINGS">FIG. 20</figref>.

0169<figref idref="DRAWINGS">FIG. 22</figref> is a drawing of an alternative embodiment of an expandable anchor. Expandable anchor is comprised of a proximal disk <b>237</b>, a distal disk <b>238</b>, a central cylinder <b>239</b>. The central cylinder <b>239</b> is laser cut or machined from Nitinol, titanium, stainless steel or other suitable metal. Alternatively central cylinder is molded from a plastic material previously disclosed in this application. According to various embodiments, the disks of <b>237</b> and <b>238</b> are laser cut from a flat sheet of Nitinol in a pattern as in <b>240</b> and then heat set into the final shape as in <b>237</b> and <b>238</b>. Formed disk <b>237</b> and <b>238</b> may be snap fit onto annular groove <b>242</b> of central cylinder <b>239</b> by placing hole <b>241</b> over annular groove <b>242</b>. Expandable anchor may be covered with a polymer covering as previously disclosed in this application. According to various embodiments, the disks <b>237</b>, <b>238</b> extend outwardly substantially perpendicular to a longitudinal axis of the anchor.

0170<figref idref="DRAWINGS">FIG. 23</figref> is a drawing of an alternative embodiment of an expandable anchor. Expandable anchor is comprised of a proximal disk <b>243</b>, a distal disk <b>244</b>, a central cylinder <b>245</b>. Central cylinder <b>245</b> is machined from Nitinol, titanium, stainless steel or other suitable metal. Alternatively central cylinder is molded from a plastic material previously disclosed in this application. Disk of <b>243</b> and <b>244</b> may be formed from Nitinol wire in a pattern as in <b>246</b>. Formed disk <b>246</b> may be snap fit onto annular groove <b>247</b> of central cylinder <b>247</b> by placing hole <b>248</b> over annular groove <b>247</b>. Expandable anchor may be covered with a polymer covering as previously disclosed in this application. <figref idref="DRAWINGS">FIG. 24</figref> is a drawing of expandable anchor of <figref idref="DRAWINGS">FIG. 23</figref> in a compressed state, with a sheath <b>249</b> constraining the anchor on the outside diameter.

0171<figref idref="DRAWINGS">FIG. 25</figref> is a drawing of an alternative embodiment of an expandable anchor formed from wire. Expandable anchor can be formed from a single Nitinol wire form <b>250</b>. Central cylinder <b>251</b> can be attached to wire form <b>250</b> by laser welding or adhesive bonding. Wire may be made from Nitinol, stainless steel, Elgiloy, L605, MP35N titanium, niobium or other suitable metal. The wire can be made of a solid wire, stranded wire or braided. The outer diameter or inner core of the wire may be clad or plated with gold, tantalum, plantium, iridium or other suitable material. The wire may be co-drawn (e.g., drawn filled tube—Fort Wayne Metals) and have an outer core of a high strength material such as Nitinol, stainless steel, Elgiloy, L605, titanium, niobium and an inner core of a high radio-opacity material such as gold, tantalum, plantium, iridium. Alternatively, the wire is made from plastic monofilament.

0172<figref idref="DRAWINGS">FIG. 26</figref> is a drawing of an alternative embodiment of an expandable anchor made from wire. Expandable anchor can be made from a Nitinol wire form as in <b>253</b>. Wire form <b>253</b> is attached to central cylinder <b>254</b> by inserting wire ends <b>256</b> into a receptacle in central cylinder <b>254</b>. Wire ends of wire form <b>253</b>, inserted into the central cylinder <b>254</b> may be attached to central cylinder by mechanical crimping or adhesive bonding or laser welding. Expandable anchor may be covered with ePTFE as previously disclosed to form an hour glass shaped cylinder or selective portions <b>255</b> can be covered like flower petals. The wire can be made of a solid wire, stranded wire or braided.

0173<figref idref="DRAWINGS">FIG. 27</figref> is a drawing of an alternative embodiment of an expandable anchor formed from wire. Expandable anchor can be formed from Nitinol wire forms <b>260</b> and <b>261</b>. Nitinol wire forms <b>260</b> and <b>261</b> are disk-shaped and are attached to central cylinder <b>257</b>, proximal cylinder <b>258</b> and distal cylinder <b>259</b> by inserting wire ends into receptacles <b>262</b> in cylinders <b>257</b>, <b>258</b> and <b>259</b>. Wire ends of the wire form <b>260</b> and <b>261</b> are inserted into the central cylinder <b>257</b> and may be attached to central cylinder by mechanical crimping or adhesive bonding or laser welding. The wire can be made of a solid wire, stranded wire or braided.

0174<figref idref="DRAWINGS">FIG. 28</figref> is a drawing of an alternative embodiment of an expandable anchor. Expandable anchor is comprised of outer rings <b>263</b>, <b>267</b>, inner rings <b>264</b>, <b>268</b> and wires <b>269</b>. Rings and wire may be made from Nitinol, stainless steel, Elgiloy, L605, MP35N, titanium, niobium or other suitable material. Alternatively, the rings and wire may be made from plastics such as Nylon, FEP, PTFE, Delrin, PET, peek, high density polyethylene, polycarbonate or other suitable polymer. Outer ring <b>263</b> and inner ring <b>264</b> and wire <b>269</b> are bonded together by fusing of the materials together for example by laser or TIG welding. Entire annular space <b>270</b> between ring <b>264</b> and ring <b>263</b> can be melted and reflowed together to close up the annular space <b>270</b> and combine <b>263</b>, <b>264</b> and <b>269</b> (and also <b>267</b>, <b>268</b> and <b>269</b>) into one solid mass at the outer ends of the ring. Individual wires <b>269</b> are not bonded except in the area near the outer ends of the rings. Alternatively, the rings <b>263</b>, <b>264</b>, <b>267</b>, <b>268</b> and wires <b>269</b> are bonded together by spot welding or adhesive bonding. The wires may be in the form of round wires <b>269</b>, flat wires <b>265</b>, or stranded wires <b>266</b>. After the rings and wires have been joined together the rings <b>263</b> and <b>267</b> can be compressed towards each other axially to reduce the axial spacing between the rings and cause the wires <b>269</b> to bend and cause the original cylinder shape to transform into a disk-shaped anchor <b>270</b>. Alternatively the anchor can be shaped to form a spherical shape or a barrel shape. The diameter of the rings <b>263</b>, <b>264</b>, <b>267</b>, <b>268</b> can range from 3 to 14 mm in diameter and the outer diameter of the disk <b>270</b> can range in the 12 to 50 mm diameter range in the expanded state and in the 3 to 14 mm diameter in the unexpanded state. The anchor can be actuated from the collapsed state to the actuated state by mechanical means or by the elastic properties of the wires <b>269</b> which can allow the anchor to self open to the disk-shaped state without mechanical actuation.

0175<figref idref="DRAWINGS">FIG. 29</figref> is a drawing of anchor previously disclosed in <figref idref="DRAWINGS">FIG. 28</figref> in which the anchor is formed into alternative shapes. Ring <b>263</b> can be rotated in the opposite direction from ring <b>267</b> to form wires <b>269</b> to an alternative pattern in which the wires <b>269</b> are formed into patterns as in <b>270</b> or <b>271</b>. Shape <b>272</b> is a disk-shaped anchor with a wire pattern of <b>270</b> or <b>271</b>. Shape <b>274</b> is a concave shaped disk, wires <b>269</b> may be formed into the pattern of <b>270</b>, <b>271</b> or as in <figref idref="DRAWINGS">FIG. 28</figref>. Shape <b>273</b> is a spherical shaped anchor. Shape <b>275</b> is an alternative shape to form the disk.

0176<figref idref="DRAWINGS">FIG. 30</figref> is a drawing of an assembly of two of the expandable anchors previously disclosed in <figref idref="DRAWINGS">FIG. 28</figref> and <figref idref="DRAWINGS">FIG. 29</figref>. Anchors <b>276</b> and <b>277</b> can be any of the alternatives from <figref idref="DRAWINGS">FIG. 28</figref> and <figref idref="DRAWINGS">FIG. 29</figref>. The anchors are assembled onto a central cylinder <b>278</b>. The spacing <b>280</b> between the two anchors can be adjusted to accommodate different pylorus widths. Expandable anchors can be covered with a polymer as previously disclosed in this application. <figref idref="DRAWINGS">FIG. 31</figref> is a cross-sectional view of the pyloric antrum <b>104</b>, pylorus <b>106</b>, duodenal bulb <b>107</b> and the duodenum <b>112</b> in the human body. An expandable anchor as disclosed in <figref idref="DRAWINGS">FIG. 28</figref>, <figref idref="DRAWINGS">FIG. 29</figref> and <figref idref="DRAWINGS">FIG. 30</figref> and intestinal bypass sleeve <b>111</b> is implanted across the pylorus.

0177<figref idref="DRAWINGS">FIG. 32</figref> is a drawing of an alternative embodiment of an expandable anchor formed in the shape of a toroidal-shaped coil compression spring <b>282</b>. The toroidal-shaped anchor may be first formed by winding a straight compression spring <b>281</b>. The compression spring <b>281</b> may be made from round wire <b>286</b>, rectangular wire <b>287</b>, square wire <b>288</b> or elliptical wire <b>289</b>. The compression spring <b>281</b> can be wound to have a round shape <b>290</b>, rectangular shape <b>291</b>, square shape <b>292</b>, or an elliptical shape <b>293</b>. The wire may be made from Nitinol, stainless steel, Elgiloy, L605, MP35N titanium, niobium or other suitable metal. The wire is, in various embodiments, made of a solid wire but can alternatively be made of stranded or braided wire. The outer diameter or inner core of the wire may be clad or plated with gold, tantalum, plantium, iridium or other suitable material. The wire may be co-drawn (e.g., drawn filled tube—Fort Wayne Metals) and have an outer core of a high strength material such as Nitinol, stainless steel, Elgiloy, L605, MP35N, titanium, niobium and an inner core of a high radio-opacity material such as gold, tantalum, plantium, iridium. Alternatively, the wire is made from a plastic monofilament such as peek, PET or delrin. Compression spring <b>281</b> is formed into a toroidal shape by bending spring ends towards each other and joining spring ends at connector <b>295</b>. A perspective view of the torroidal spring is shown in <b>294</b>. A drawstring <b>283</b> is contained within the center of the toroidal spring <b>282</b>. The drawstring <b>283</b> is threaded through a hole in the connector <b>295</b>. Drawstring <b>283</b> is terminated at spheres <b>284</b> that can be crimped onto the end of the drawstring <b>283</b>. The spheres may be made of metal or plastic and may be attached to the drawstring <b>283</b> by crimping, welding, gluing, insert molding or other suitable means. The drawstring may be comprised of plastic or metal and may be made of a monofilament or braided cable material. When spheres <b>284</b> are withdrawn from connector <b>295</b>, drawstring <b>283</b> is tensioned and the diameter of the toroidal spring is reduced to the smaller diameter as in <b>285</b>.

0178<figref idref="DRAWINGS">FIG. 33A</figref> is a drawing of an alternative embodiment of an expandable anchor formed in the shape of a toroidal-shaped coil as previously disclosed in <figref idref="DRAWINGS">FIG. 32</figref>. The coil may have small tissue penetrating anchors <b>296</b> on the outer surface of the coil. Tissue penetrating anchor <b>296</b> may be made from, stainless steel, Elgiloy, L605, MP35N, titanium or niobium and may be crimped onto the wire or welded. Tissue penetrating anchors <b>296</b> may be an optional feature that can be added if the patient's anatomy does not have a pyloric ring that is adequate for anchoring. <figref idref="DRAWINGS">FIG. 33B</figref> is a drawing of an alternative embodiment of an expandable anchor formed in the shape of a toroidal-shaped coil as previously disclose in <figref idref="DRAWINGS">FIG. 32</figref>. The toroidal-shaped spring is formed of segments where the direction of the winding of the coil is reversed to cancel out the helical twisting action of the spring. The individual segments <b>297</b>, <b>298</b>, <b>299</b> and <b>300</b> can be connector at joiners <b>301</b>. Alternatively the entire toroidal spring can be laser cut as one unitary piece by laser cutting the wound coil in the unformed shape as in <b>281</b> from a piece of round tubing. <figref idref="DRAWINGS">FIG. 33C</figref> is a drawing of an alternative embodiment of an expandable anchor formed in the shape of a toroidal-shaped coil as previously disclose in <figref idref="DRAWINGS">FIG. 32</figref>. The spring is wound to have double helices that are 180 degrees offset from each other.

0179<figref idref="DRAWINGS">FIG. 34A</figref> is an alternative embodiment of a toroidal spring that is made from laser cutting a pattern into a round piece of Nitinol tubing. The Nitinol tubing is laser cut in the straight tubular shape and then the cut tube is then formed into the toroidal shape. Spring elements <b>301</b> and <b>302</b> elastically bend when the diameter of the toroidal spring is reduced. Bending of elements <b>301</b> and <b>302</b> reduces the included angles <b>303</b> and <b>309</b> and space <b>304</b> reduces to allow the diameter of toroidal spring to be compressed. <figref idref="DRAWINGS">FIG. 34B</figref> is an alternative embodiment of a toroidal spring that is made from laser cutting a pattern into a round piece of Nitinol tubing. The Nitinol tubing is laser cut in the straight round tubular shape and then it is formed into the toroidal shape. Alternatively the part may be cut from a flat sheet of Nitinol and then shape set into the final shape. Spring elements <b>306</b> and <b>305</b> elastically bend when the diameter of the toroidal spring is reduced. Bending of elements <b>306</b> and <b>305</b> reduces the included angles <b>307</b> and angle <b>308</b> to allow the diameter of the toroidal spring to be compressed.

0180<figref idref="DRAWINGS">FIG. 35</figref> is a drawing of an alternative embodiment of an expandable anchor as disclosed in <figref idref="DRAWINGS">FIG. 32</figref> and <figref idref="DRAWINGS">FIG. 33</figref>. Toroidal-shaped springs <b>310</b>, <b>311</b> and <b>312</b> are joined together side-by-side and integrated into an anchor together. In various embodiments, 1 to 3 springs will typically be used together, but in some configurations up to 100 springs may be joined side-by-side at some small spacing. Spring <b>316</b>, <b>317</b> and <b>318</b> are assembled in a coaxial arrangement (one spring coaxial within the center of another) to provide for a combined spring with increased compression resistance. The direction of the spring winding for the three coaxial springs may be alternated. Springs <b>313</b>, <b>314</b> and <b>315</b> are also coaxial springs that are wound in an elliptical shape.

0181<figref idref="DRAWINGS">FIG. 36</figref> is an assembly drawing of an expandable anchor assembly. Expandable anchor assembly comprises two toroidal springs <b>327</b> as previously disclosed which are placed into pockets <b>322</b> to form disks <b>319</b> and <b>320</b>, central cylinder <b>324</b> is located in between disks <b>319</b> and <b>320</b>. Pockets <b>322</b> are formed from a polymer membrane <b>321</b> from materials previously disclosed in this application. Polymer membrane <b>321</b> is attached to central cylinder at pins <b>326</b>. Outflow opening <b>325</b> provides for a location to attach the intestinal bypass sleeve <b>111</b>. Inflow opening <b>323</b> is positioned towards the pyloric antrum <b>104</b>. Drawstring <b>328</b> can be withdrawn from the toroidal spring assembly to compress and retrieve the device.

0182<figref idref="DRAWINGS">FIG. 37</figref> is an assembly drawing of a fixed diameter cylinder for the central pyloric portion of the invention herein disclosed. The central cylinder <b>324</b> is ridge and provides a means to attach the polymer membrane to the central cylinder at disks <b>329</b> and <b>330</b>. Securement rings <b>331</b> and <b>332</b> penetrate through holes in the polymer membrane and into holes in the central cylinder. Securement rings <b>331</b> and <b>332</b> can be fastened to the disks <b>329</b> and <b>330</b> by diameter interference of the pins with the holes, by welding, gluing or mechanical fasteners.

0183<figref idref="DRAWINGS">FIG. 38</figref> is drawing of a central cylinder pyloric portion for use with any of the anchor embodiments herein disclosed in which the mid-portion allows for normal opening and closing of the pylorus. There is a first ring <b>333</b> and a second ring <b>334</b> which are fixed rigidly together by connector links <b>335</b>, <b>338</b> or <b>337</b>. The connector links cross through the pyloric aperture <b>105</b> while not obstructing the pyloric aperture <b>105</b> or limiting opening or closing of the pylorus. In various embodiments, a thin polymeric membrane will be used over both rings <b>333</b>, <b>334</b> and will span the space between the two rings as disclosed in <figref idref="DRAWINGS">FIG. 39</figref>. The pylorus <b>106</b> can close by entering into the space <b>339</b> in between rings <b>333</b> and <b>334</b> to open and close. Rigid linking of rings <b>333</b> and <b>334</b> provides for a rigid structure to anchor expandable anchors to and helps to keep expandable anchor (disks) oriented in the proper orientation without canting within the pyloric antrum or duodenal bulb. The rigid linking also does not allow rotational movement between the two rings <b>333</b> and <b>334</b> and still allows for normal opening and closing of the pylorus, Rotational movement between <b>333</b> and <b>334</b> may cause the pyloric polymer membrane <b>340</b> portion to close. The expandable anchors in the pyloric antrum and the duodenal bulb are tethered to the first ring <b>333</b> and second ring <b>334</b> by a polymer membrane.

0184<figref idref="DRAWINGS">FIG. 39</figref> is a sectional view of the invention herein disclosed implanted into the pyloric antrum <b>104</b>, pylorus <b>106</b> and duodenal bulb <b>107</b> and duodenum <b>112</b>. The anchoring device is comprised of two disk-shaped expandable anchors <b>341</b> and <b>342</b> that are connected to a central cylinder which has a thin-walled compliant membrane <b>340</b> over the central portion to allow opening and closing of the pyloric aperture. Central cylinder has rings <b>333</b> and <b>334</b> which are linked by a connector link <b>335</b>. Compliant membrane <b>340</b> is free to open and close with the movement of the pylorus <b>106</b>. Expandable anchors <b>341</b> and <b>342</b> are tethered to rings <b>333</b> and <b>334</b> by a polymer membrane <b>343</b>.

0185<figref idref="DRAWINGS">FIG. 40</figref> is a sectional view of the invention herein disclosed implanted into the pyloric antrum <b>104</b>, pylorus <b>106</b>, duodenal bulb <b>107</b> and duodenum <b>112</b>. The anchoring device is comprised of two disk-shaped expandable anchors <b>341</b>, <b>342</b> as previously disclosed in this application that are connected to a rigid central cylinder <b>344</b>. The lumen of the anchoring device has a one way anti-reflux valve <b>346</b> and a flow limiter <b>345</b>. Drawstring <b>347</b> can be tensioned to collapse the diameter of the expandable anchors for removal and for loading the device onto a delivery catheter.

0186<figref idref="DRAWINGS">FIG. 41</figref> is a sectional view of the invention herein disclosed implanted into the pyloric antrum <b>104</b>, pylorus <b>106</b>, duodenal bulb <b>107</b> and duodenum <b>112</b>. The anchoring device is comprised of two disk-shaped expandable anchors <b>341</b>, <b>342</b> as previously disclosed in this application that are connected to a central cylinder <b>350</b>. The tube of central cylinder is elastically compressible in diameter so that the diameter can be compressed from the first state <b>349</b> to reduced diameter state <b>348</b>. This will provide for a smaller profile on the delivery catheter. In some configurations, the central cylinder can be soft enough to allow pylorus movement to compress the central cylinder and close the central cylinder opening when the pylorus closes. Drawstring <b>347</b> can be tensioned to collapse the diameter of the expandable anchors for removal and for loading the device onto a delivery catheter.

0187<figref idref="DRAWINGS">FIG. 42</figref> is a sectional view of the invention herein disclosed implanted into the pyloric antrum <b>104</b>, pylorus <b>106</b>, duodenal bulb <b>107</b> and duodenum <b>112</b>. The anchoring device is comprised of two disk-shaped expandable anchors <b>341</b>, <b>342</b> as previously disclosed in this application that are connected to rings <b>352</b> and <b>353</b>. The rings <b>353</b>, <b>353</b> are not rigidly connected to each other. Thin-walled central membrane <b>351</b> is connected to the two rings <b>352</b> and <b>353</b>. Central membrane can open and close with the pylorus. Drawstring <b>347</b> can be tensioned to collapse the diameter of the expandable anchors for removal and for loading the device onto a delivery catheter.

0188<figref idref="DRAWINGS">FIG. 43</figref> is a sectional view of the invention herein disclosed implanted into the duodenal bulb <b>107</b> and duodenum <b>112</b>. The anchoring device is comprised of two disk-shaped expandable anchors <b>341</b>, <b>342</b> as previously disclosed in this application that are connected to a rigid central cylinder <b>344</b>. The lumen of the anchoring device has a one way anti-reflux valve <b>346</b> and a flow limiter <b>345</b>. Drawstring <b>347</b> can be tensioned to collapse the diameter of the expandable anchors for removal and for loading the device onto a delivery catheter.

0189<figref idref="DRAWINGS">FIG. 44</figref> is a sectional view of the invention herein disclosed implanted into the pyloric antrum <b>104</b>, pylorus <b>106</b>, duodenal bulb <b>107</b> and duodenum <b>112</b>. The anchoring device is comprised of two disk-shaped expandable anchors <b>341</b>, <b>342</b> as previously disclosed in this application that are connected to a rigid central cylinder <b>344</b>. Drawstring <b>347</b> can be tensioned to collapse the diameter of the expandable anchors for removal and for loading the device onto a delivery catheter. Intestinal bypass sleeve <b>111</b> crosses the pylorus <b>106</b> and can be compressed shut at <b>354</b> by the pylorus <b>106</b>.

0190<figref idref="DRAWINGS">FIG. 45A</figref> is a sectional view of the invention herein disclosed implanted into the pyloric antrum <b>104</b>, pylorus <b>106</b>, duodenal bulb <b>107</b> and duodenum <b>112</b>. The anchoring device is comprised of two disk-shaped expandable anchors <b>341</b>, <b>342</b> as previously disclosed in this application that are connected to a rigid central cylinder <b>344</b>. Additional expandable anchors <b>355</b>, <b>356</b>, <b>357</b> and <b>358</b> are extended into the pyloric antrum <b>104</b>.

0191<figref idref="DRAWINGS">FIG. 45B</figref> is a drawing of a flat braided expandable anchor made from Nitinol wire. A series of dowels pins <b>504</b> is press fit into an aluminum plate in a determined pattern. Eight wires <b>506</b> are braided into a flat braid by wrapping the wires around the dowel pins <b>504</b> and then braiding one wire over, one wire under. Four wires are braided in each diagonal direction. Wires are doubled up at end locations <b>505</b> and <b>507</b>. After the braiding pattern is complete, the wires and the plate are heat set in a salt bath at 500 degrees centigrade for 10 minutes and then water quenched to room temperature. Heat set wire flat braid <b>508</b> is then removed from the forming fixture and the wires retain the heat set shape mandrel from the fixture. Flat braid <b>508</b> is then wrapped around a round mandrel to form a cylinder shaped braid <b>509</b>. The wire ends <b>505</b> and <b>507</b> at the end of the flat braid are joined at <b>510</b>.

0192<figref idref="DRAWINGS">FIG. 46</figref> is a drawing of an alternative embodiment of the invention herein disclosed. The expandable anchor is comprised of a hollow tubular braided structure of wire. The tubular braid can be braided in the diameter range from 10 mm in diameter up to about 70 mm in diameter. The wire diameter can range from 0.001 inch to 0.014 inch. In exemplary embodiments, the number of wire ends in the braid is 96 ends, but it can range from as few as 4 ends up to 256 ends. The wire can be made from a metal such as Nitinol, MP35N, L605, Elgiloy, stainless steel or from a plastic such as Pet, Peek or Delrin or other suitable material. The tubular wire braid is formed into a shape with a disk <b>360</b>, a central cylinder portion <b>363</b>, cylindrical portion <b>359</b>. Wire ends are gathered into bunches <b>361</b> and welded together or a sleeve is crimped onto wires to keep the braided ends from fraying and unraveling. Alternatively, the structure could be made from a braid using a single wire end. Central cylinder <b>363</b> has a through lumen <b>362</b> that allows chyme to flow from the stomach to the duodenum. The central cylinder <b>363</b> can be rigid to hold the pylorus <b>106</b> open or it may be compliant to allow the opening and closure of through lumen <b>362</b> with the pylorus.

0193The length of the device is typically about 50 mm but can range from about 10 mm to 100 mm. The diameter of the cylindrical portion <b>359</b> is typically about 25 mm in diameter, but can range from 10 mm to 75 mm. The diameter of the central cylinder portion is typically about 10 mm in diameter but can range from 2 mm up to 25 mm in diameter. The length of the central cylinder <b>363</b> is approximately that of the width of the pylorus, but the central cylinder <b>363</b> can be slightly longer to provide a gap between central cylinder and pylorus or slightly shorter to provide for a compressive force to be applied to the pylorus. The expandable anchor is compressible in diameter and the diameter can be reduced to about 5 to 10 mm in diameter typically to allow the anchor to be loaded into a catheter. The expandable anchor can be covered on the outside and/or inside side with a polymer membrane covering. The membrane <b>365</b> covering the expandable anchor may be made from a thin-walled polymer material such as silicone, polyurethane, polytetrafluoroethylene, fluorinated ethylene propylene, polyethylene, expanded poly tetrafluoroethylene (ePTFE) or other suitable material. In some embodiments, the wall thickness of the membrane covering the expandable anchor may be in the range of 0.001 inch to 0.030 inch thick. The membrane <b>365</b> may be made by extrusion, dip coating from a liquid solution, powder coated from fine particles of polymer or paste extruded and then stretched as is the case with ePTFE. The expandable anchor membrane <b>365</b> may also be cut from a flat sheet of material such as ePTFE and then bonded or sewn into a disk shape or spherical shaped structure and then attached to the expandable anchor by sewing or gluing with a polymer such as FEP.

0194<figref idref="DRAWINGS">FIG. 47</figref> is a sectional view of the invention herein disclosed in <figref idref="DRAWINGS">FIG. 46</figref> implanted into the pyloric antrum <b>104</b>, pylorus <b>106</b>, duodenal bulb <b>107</b> and duodenum <b>112</b>. An intestinal bypass sleeve <b>111</b> is attached to the anchor.

0195<figref idref="DRAWINGS">FIG. 48</figref> is a drawing of an alternative embodiment of the invention herein disclosed in <figref idref="DRAWINGS">FIG. 46</figref>. The expandable anchor is comprised of a hollow tubular braided structure of wire. The wire form has been shaped to conform to the shape of the pylorus and the duodenal bulb. The expandable anchor has an annular grove <b>366</b> formed in the wall of the duodenal bulb portion of the expandable anchor. The annular groove <b>366</b> is sized to provide for a modular connection means between an expandable anchor and intestinal bypass sleeve <b>111</b>. <figref idref="DRAWINGS">FIG. 49</figref> is a sectional view of the invention herein disclosed in <figref idref="DRAWINGS">FIG. 48</figref> implanted into the pyloric antrum <b>104</b>, pylorus <b>106</b>, duodenal bulb <b>107</b> and duodenum <b>112</b>. An intestinal bypass sleeve <b>111</b> is attached to the anchor at annular groove <b>366</b> and anchored with a second expandable anchor <b>367</b>.

0196<figref idref="DRAWINGS">FIG. 50</figref> is a drawing showing the process steps for the manufacturing of the expandable anchor as in <figref idref="DRAWINGS">FIG. 46</figref>, <figref idref="DRAWINGS">FIG. 47</figref> and <figref idref="DRAWINGS">FIG. 48</figref>. Braided Nitinol wire tube <b>368</b> is placed onto mandrel <b>369</b>, one clamp <b>370</b> is tightened and then the braid is smoothed and longitudinally tightened on the mandrel <b>369</b>. The second clamp <b>370</b> is then tightened to secure braid <b>368</b> onto mandrel. Braid <b>368</b>, secured on mandrel <b>369</b> is then heat set in a salt bath for 5 minutes at a temperature of 500 degrees centigrade. The mandrel and braid is then removed from the salt bath and rapidly cooled by immersing braid and mandrel into a room temperature water bath. Clamps <b>370</b> are then removed from the braid <b>368</b> and mandrel <b>369</b> and the braid <b>368</b> is removed from the mandrel. One end of heat set braid <b>368</b> is then inverted through the lumen of <b>368</b> to point <b>371</b> to form a layer of double braid from the left end to point <b>371</b>. Braid is then placed onto mandrel <b>372</b> and the left end of braid <b>372</b> is lined up to point <b>373</b>. End of overlapped braid is located at <b>371</b>. Braid is then secured to the mandrel <b>372</b> at location <b>374</b> by a wire clamp and at locations <b>375</b> by two additional clamps. A secondary heat set is then performed on mandrel <b>372</b> and braid in a salt bath for 5 minutes at a temperature of 500 degrees centigrade. The mandrel and braid is then removed from the salt bath and rapidly cooled by immersing braid and mandrel into a room temperature water bath. Clamps <b>374</b>, <b>375</b> are then removed from the braid and the braid is removed from the mandrel <b>372</b>. The braid now has permanently taken on the shape of the mandrel <b>372</b> and has the narrow central cylinder <b>377</b> shape. The braid length is trimmed at <b>376</b>. All the ends of wires in the braid from both layers are at the end of braid at location <b>376</b>. Wire ends are gathered and secured at location <b>378</b>

0197<figref idref="DRAWINGS">FIG. 51</figref> is a drawing of an alternative embodiment of an expandable anchor <b>379</b>. Expandable anchor <b>379</b> is comprised of a proximal expandable disk <b>381</b>, a distal expandable disk <b>380</b>, a central cylinder <b>382</b> and spring arms <b>383</b>. The function and materials are similar to the anchor disclosed in <figref idref="DRAWINGS">FIG. 18</figref>. Spring arms <b>384</b> and <b>385</b> are formed inwards to form to concave shaped disk surfaces toward the central cylinder <b>382</b>. Gap <b>386</b> between disks <b>380</b> and <b>381</b> can be elastically opened and closed by bending spring arms <b>384</b> and <b>385</b>. <figref idref="DRAWINGS">FIG. 52A</figref> is a drawing of a pyloric antrum <b>104</b>, pylorus <b>106</b>, duodenal bulb <b>107</b> and duodenum <b>112</b> and of the expandable anchor <b>379</b> of <figref idref="DRAWINGS">FIG. 52</figref>. The pylorus width is shown by reference <b>387</b>. <figref idref="DRAWINGS">FIG. 52B</figref> is a drawing of a pyloric antrum <b>104</b>, pylorus <b>106</b>, duodenal bulb <b>107</b> and duodenum <b>112</b> and of the expandable anchor <b>379</b> of <figref idref="DRAWINGS">FIG. 52</figref> implanted into it. The pyloric width <b>387</b> is greater than anchor width or gap <b>386</b>. The pyloric width <b>387</b> has been reduced to a narrower width <b>388</b> due to clamping action of the anchor <b>379</b>.

0198<figref idref="DRAWINGS">FIG. 53</figref> is a drawing of an alternative embodiment of an expandable anchor <b>389</b>. The function and materials are similar to the anchor disclosed in <figref idref="DRAWINGS">FIG. 6</figref>. Spring arms <b>392</b> and <b>391</b> are formed inwards to form to concave shaped disk surfaces toward the central cylinder <b>393</b>. Gap <b>390</b> between arms <b>392</b> and <b>391</b> can be elastically opened and closed by bending spring arms <b>392</b> and <b>391</b>. Expandable anchor <b>389</b> can clamp on the pylorus in a similar manner as disclosed in <figref idref="DRAWINGS">FIG. 52</figref><i>b. </i>

0199<figref idref="DRAWINGS">FIG. 54</figref> is a drawing of an alternative embodiment of a single disk of expandable anchor <b>394</b> that has optional barbs <b>395</b> to provide for an additional securing means to the pylorus. <figref idref="DRAWINGS">FIG. 55</figref> is a sectional view of the invention herein disclosed implanted into the pyloric antrum <b>104</b>, pylorus <b>106</b>, duodenal bulb <b>107</b> and duodenum <b>112</b>. The anchoring device is comprised of two disk-shaped expandable anchors <b>394</b> that are connected to a central cylinder <b>396</b> and <b>397</b>. The central cylinder of the device <b>396</b> and <b>397</b> in between the two anchor rings <b>394</b> can be made from plastic material such as Delrin, peek, high density polyethylene, polycarbonate or other suitable polymer. The central cylinder portion <b>396</b>, <b>397</b> may also be made from stainless steel, titanium or Nitinol. The fixed diameter of the pyloric portion pieces <b>396</b> and <b>397</b> of the device can be sized to provide for a full opening of the pylorus and not allow the pylorus to close normally. The length of the pyloric portion of the device <b>400</b> can be adjusted by sliding the outer cylinder <b>396</b> over inner cylinder <b>397</b> by sliding on the ratcheting mechanism. This will change the spacing between the anchor rings <b>394</b> and will allow the device to be adjusted for ring spacing in-situ. It may be desirable to change the ring spacing to accommodate differences in the pylorus <b>106</b> dimensions from patient to patient. It may also be desirable to change the length <b>400</b> of the central cylinder portion to allow the anchor ring <b>394</b> spacing to be adjusted to allow the expandable anchor to put a clamping force on to the pylorus in a longitudinal direction. The mechanism used for <b>398</b> and <b>399</b> could also be a screw thread arrangement such as a male thread on <b>398</b> and a female thread on <b>399</b>. In various embodiments, the inside diameter of the central cylinder <b>396</b> and <b>397</b> ranges from as small as 2 mm in diameter up to as large as 14 mm in diameter. The central lumen of device has a one-way anti-reflux valve <b>401</b>. The anti-reflux valve <b>401</b> allows for unobstructed flow in the direction of the stomach antrum <b>104</b> to the duodenal bulb <b>107</b>, but limits flow in the reverse direction. The anti-reflux valve <b>401</b> can be constructed of a duck bill design with two flexible leaflets, or may utilize other designs such as a tri-leaflet valve or quad-leaflet valve. The anti reflux valve may be constructed of silicone, polyurethane, polyethylene, ePTFE or other suitable polymer. The diameter of the central cylinder is fixed, but it may also be designed to allow it to be reduced in diameter during loading of the device onto a catheter.

0200<figref idref="DRAWINGS">FIG. 56</figref> is a sectional view of the invention herein disclosed implanted into the pyloric antrum <b>104</b>, pylorus <b>106</b> and duodenal bulb <b>107</b> and duodenum <b>112</b>. The anchoring device is comprised of two toroidal-shaped expandable anchors <b>402</b> that are connected to a central cylinder <b>403</b>. The diameter of the central cylinder <b>403</b> is fixed, but it may also be elastic to allow it to be reduced in diameter during loading of the device onto a catheter. An optional needle <b>404</b>, suture, T-bar <b>405</b>, hollow helical anchor <b>406</b> or screw type anchor <b>407</b> is inserted into and/or through the tissue of the pylorus <b>106</b>, pyloric antrum <b>104</b> or duodenum <b>107</b> to provide additional anchoring and securement of the intestinal bypass sleeve <b>111</b> anchoring device to the pylorus anatomy <b>106</b>. The T-Bar <b>405</b> is anchored by a tensioning member <b>408</b> and cincher <b>409</b>.

0201<figref idref="DRAWINGS">FIG. 57</figref> is a sectional view of the invention herein disclosed implanted into the pyloric antrum <b>104</b>, pylorus <b>106</b>, duodenal bulb <b>107</b> and duodenum <b>112</b>. An expandable ring <b>402</b> is sized large enough in diameter to engage the wall of the pyloric antrum <b>104</b>. The central portion of the device is constructed of a ridged fixed diameter central cylinder <b>403</b>, or alternatively a compressible cylinder or a thin-walled sleeve. An optional needle <b>404</b>, suture, T-bar, hollow helical anchor <b>406</b> or screw type anchor <b>407</b> is inserted into and or through the tissue of the pylorus <b>106</b>, pyloric antrum <b>104</b> or duodenum <b>112</b> to provide additional anchoring and securement of the intestinal bypass sleeve <b>111</b> and anchoring device to pylorus anatomy <b>106</b> or other suitable location. The T-Bar <b>405</b> is anchored by a tensioning member <b>408</b> and cincher <b>409</b>.

0202<figref idref="DRAWINGS">FIG. 58</figref> is a cross-sectional view of a portion of the digestive tract in a human body. An intestinal bypass sleeve <b>111</b> is implanted in the duodenum <b>112</b> from the pylorus <b>106</b> to the ligament of treitz <b>109</b>. The sleeve is held in place at the pylorus <b>106</b> by expandable anchors <b>410</b> that anchor on the pylorus <b>106</b> optional secondary expandable anchors <b>411</b> anchor the intestinal bypass sleeve <b>111</b> at additional locations in the duodenum <b>112</b> and jejunum <b>113</b>. An expandable anchor <b>412</b> with an anti-reflux valve is implanted at the gastro esophageal (GE) junction <b>102</b> to help resolve gastroesophageal reflux disease (GERD). Reference numbers <b>414</b>, <b>415</b>, <b>416</b>, <b>417</b>, <b>418</b> and <b>419</b> denote valve designs that have from two to seven flaps in the valve and may be used for the anti-reflux device <b>413</b>.

0203<figref idref="DRAWINGS">FIG. 59A</figref> is a drawing of an alternative embodiment of an expandable anchor. Expandable anchor has a cylindrical portion <b>420</b>, spring arms <b>421</b>, a central cylinder portion <b>422</b>, through lumen <b>423</b> and an isometric view of the expandable anchor <b>427</b>. Expandable anchor is laser cut from Nitinol tubing and heat set to final shape on a mandrel with processing steps as previously disclosed in this application. Large diameter cylindrical portion <b>420</b> has a diameter in the range from 10 to 70 mm. <figref idref="DRAWINGS">FIG. 59B</figref> is a drawing of an alternative embodiment of an expandable anchor. Expandable anchor has a cylindrical portion <b>424</b>, spring arms <b>425</b>, through lumen <b>426</b> and an isometric view of the expandable anchor <b>428</b>. Expandable anchor is laser cut from Nitinol tubing and heat set to final shape on a mandrel with processing steps as previously disclosed in this application. Large diameter cylindrical portion <b>424</b>, according to various embodiments, has a diameter in the range from 10 to 70 mm. <figref idref="DRAWINGS">FIG. 59C</figref> is a drawing of an alternative embodiment of an expandable anchor. Expandable anchor <b>429</b> is a double-sided version of anchor as in <figref idref="DRAWINGS">FIG. 59C</figref>. <figref idref="DRAWINGS">FIG. 60</figref> is a drawing of <figref idref="DRAWINGS">FIG. 59A</figref> and an intestinal bypass sleeve <b>111</b> implanted into a pyloric antrum <b>104</b>, pylorus <b>106</b> duodenal bulb <b>107</b> and duodenum <b>112</b>. Alternatively, <figref idref="DRAWINGS">FIG. 59B</figref> and <figref idref="DRAWINGS">FIG. 59C</figref> could also be implanted into the pyloric antrum <b>104</b>, duodenal bulb <b>107</b>, duodenum <b>112</b> or GE junction <b>102</b>.

0204<figref idref="DRAWINGS">FIG. 61A</figref> is a drawing of an intestinal bypass sleeve with a diameter transition from a larger diameter to a smaller diameter. Intestinal bypass sleeve is comprised of three sections: a first tube <b>430</b>, a second tube <b>432</b>, and a transitional piece <b>431</b>. Intestinal bypass sleeve is made from a polymer material such as ePTFE, PTFE, FEP, polyurethane, silicone, polyethylene, cross-linked polyethylene, high density polyethylene, polypropylene or other suitable material. The intestinal bypass sleeve may be dip coated in one-piece with all three components <b>430</b>, <b>431</b>, and <b>432</b> made into a seamless one-piece unitary structure. Alternatively <b>430</b>, <b>431</b> and <b>432</b> can be made as separate components and they can be joined by adhesive bonding (such as with silicone adhesive) or FEP hot melt adhesive, or they can be sewn together at seams <b>434</b>, <b>435</b>, <b>436</b> using suture such polyester, Nylon, polypropylene, PTFE or ePTFE. Intestinal bypass sleeve may range in diameter from 3 to 80 mm. Intestinal bypass sleeve may have a wall thickness in the range of 0.001 inch to 0.060 inch thick.

0205Intestinal bypass sleeve may be made porous or nonporous. Sleeve may have surface coatings to close up pores of porous membrane. Such as a surface coating of silicone, polyurethane, FEP applied to porous substrate to render it non-permeable. ePTFE is inherently hydrophobic and has some resistance to water penetration, but it may be desirable to have a higher water entry pressure or make ePTFE impermeable. Intestinal bypass sleeve may have a lubricious (or sticky) hydrophilic coating or a hydrogel added to the inner or outer surface to reduce the friction of the surface or to make it easier for food to pass through the liner or to decrease the outer surface coefficient of friction or make the sleeve stay in place better in the intestines. Intestinal bypass sleeve or expandable anchor may be used for drug delivery, delivery of peptides or other therapeutics by incorporating a drug or peptide into the polymer wall thickness of the intestinal bypass sleeve. The drug or peptide may be added directly to the surface of the intestinal liner without a polymer or covalently bonded to the polymer surface.

0206The drug or peptide may be eluted from a surface coating on the sleeve or anchor which incorporates the drug into the coating. Polymers that may be used as a coating to elute a drug include silicone, polyurethane, Polyvinyl Alcohol, Ethylene vinyl acetate, Styrene acrylonitrile, Styrene-Butadiene, Pebax or other suitable polymer. Absorbable polymers that may be used for drug delivery include, Polyglycolic acid (PGA), Polylactide (PLA), Poly(ε-caprolactone), Poly(dioxanone) Poly(lactide-co-glycolide) or other suitable polymer. Other suitable coatings for increased biocompatibility or drug release may include human amnion, collagen Type I, II, III, IV, V, VI—Bovine, porcine, or ovine. The coating on the intestinal bypass sleeve can also take the form of a liquid that can be used to release the drug or peptide include, Vitamin D, A, C, B, E, olive oil, polyethylene glycol, vegetable oils, essential fatty acids, alpha-linolenic acid, lauric acid, linoleic acid, gamma-linolenic acid, palmitoleic acid or other suitable liquids. The drug may serve to increase satiety, to interrupt the secretion of secondary hormones or digestive enzymes, release antibacterial agents to reduce infection, to increase the fibrotic reaction of the intestinal tract, to decrease the fibrotic reaction of the intestinal tract, to target changes in the cellular composition such as decreasing the number of receptor cells in the duodenum.

0207Intestinal bypass sleeve can release cholecystokinin, gastrin, secretin, gastric inhibitory peptide, motilin, glucagon like peptide 1, bile, insulin, pancreatic enzymes, ghrelin, penicillin, amoxicillin, ampicillin, carbenicillin, cloxacillin, dicloxacillin, nafcillin, oxacillin, penicillin g, penicillin V, Piperacillin, Ticarcillin Aminoglycosides, Amikacin, Gentamicin, Kanamycin, Neomycin, NEO-RX, Netilmicin, Streptomycin, Tobramycin, Carbapenems, Ertapenem, Doripenem, DORIBAX, Emipenem-cilastatin, Meropenem, Cefadroxil, Cefazolin, Cephalexin rapymicin, taxol, vitamin A, vitamin C, vitamin D, vitamin B, vitamin E, fatty acids, oils, vegetable oils, aspirin, somastatin, motilin, trypsinogen, chymotrypsinogen, elastase, carboxypeptidase, pancreatic lipase, amylase, enteroglucagon, gastric inhibitory polypeptide, Vasoactive intestinal peptide, PYY, Peptide Tyrosine Tyrosine, Leptin, Pancreatic polypeptide.

0208<figref idref="DRAWINGS">FIG. 61B</figref> is a drawing of an alternative embodiment of an intestinal bypass sleeve. First tube <b>437</b> a V-shaped notch <b>438</b> is cut into the top and bottom surfaces of tube. V-shaped notch <b>438</b> is closed by sewing or adhesive bonding to reduce the tube diameter <b>439</b>. Intestinal bypass sleeve is made from ePTFE tubing or other polymers as previously disclosed in <figref idref="DRAWINGS">FIG. 61A</figref>.

0209<figref idref="DRAWINGS">FIG. 62A</figref> is a drawing of an alternative embodiment of an intestinal bypass sleeve. Intestinal bypass sleeve starts out as a round tube <b>440</b>. Slot <b>441</b> is cut into sleeve <b>440</b> at the top and bottom surfaces. Slot in sleeve <b>441</b> is closed by sewing or adhesive bonding at seam <b>442</b>. Final tube is an open end tube with a diameter change from the original larger diameter in <b>440</b> to the smaller diameter at <b>441</b>. <figref idref="DRAWINGS">FIG. 62B</figref> is a drawing of an alternative embodiment of an intestinal bypass sleeve. Intestinal bypass sleeve starts out as a round tube <b>443</b> of ePTFE. Tube diameter is reduced from <b>444</b> to <b>445</b> by drawing (pulling) the tube <b>444</b> through a reducing die <b>446</b>. An optional floating plug <b>447</b> can be placed inside of tube during diameter reduction. The final tube is seamless and has a large diameter section <b>450</b>, a tapered section <b>448</b>, and small diameter section <b>449</b>.

0210<figref idref="DRAWINGS">FIG. 63A</figref> is a drawing of an alternative embodiment of an intestinal bypass sleeve. Intestinal bypass sleeve starts out as a round tube <b>451</b> of ePTFE. Tube diameter is increased from <b>451</b> to <b>454</b> by pulling the tube <b>451</b> over a mandrel <b>452</b>. Tube <b>451</b> moves in direction <b>453</b> while mandrel <b>452</b> is stationery. The final tube is seamless and has a large diameter section <b>454</b>, a tapered section <b>455</b>, and small diameter section <b>456</b>. An optional final tube configuration has a large diameter section <b>457</b> and a tapered section <b>458</b>. <figref idref="DRAWINGS">FIG. 63B</figref> is a drawing of an alternative embodiment of an intestinal bypass sleeve. Intestinal bypass sleeve is made by rolling up a thin wall sheet of ePTFE around a mandrel and laminating the ePTFE sheet into a tapered tube configuration and sintering or bonding with an adhesive such as FEP. Final tube may have a large diameter section <b>459</b> a transition section <b>460</b> and a small diameter section <b>461</b>. Final wall thickness can be formed by 1 to 20 layers <b>462</b>.

0211<figref idref="DRAWINGS">FIG. 64A</figref> is drawing of a hemispherical shaped covering for an expandable anchor that is assembled from sheet material into a spherical shape. Figure “8” shape <b>463</b> is cut from a sheet of ePTFE sheet. Two shapes of <b>463</b> are joined together by sewing or adhesive bonding to produce final spherical shape <b>465</b>. Spherical shape <b>465</b> may have a hole <b>466</b> cut through one or both sides to provide for a through hole to allow attachment to an expandable anchor. <figref idref="DRAWINGS">FIG. 64B</figref> is a drawing of hemispherical shaped covering for an expandable anchor that is made by radial stretching a tube preform into a spherical shape by blow-molding or mechanical stretching. Starting shape is a tube of ePTFE <b>467</b> is tube <b>467</b>. Tube <b>467</b> is placed into mold <b>468</b> and an internal pressure or force is applied to stretch and radially orient the tube <b>467</b> to shape of inside of mold <b>468</b>. Pressure is released from tube <b>467</b> and stretched tube is removed from inside of mold <b>468</b>. Final shape of tube after removing from mold <b>468</b> is <b>469</b>. In <figref idref="DRAWINGS">FIG. 64C</figref>, reference number <b>511</b> is a drawing of a multi-lumen tubing that can be used for an expandable anchor to hold parallel toroidal springs as shown in <figref idref="DRAWINGS">FIG. 35</figref>, item <b>310</b>, <b>311</b>, <b>312</b>. Reference number <b>512</b> is a tubing extrusion with a pre-attached flange to be used with an anchor as shown in <figref idref="DRAWINGS">FIG. 39</figref> and <figref idref="DRAWINGS">FIG. 65C</figref>.

0212<figref idref="DRAWINGS">FIG. 65A</figref> is drawing of a hemispherical or disk-shaped covering for an expandable anchor that is assembled from sheet material into a spherical or disk shape. Shape <b>466</b> is cut from a sheet of ePTFE. Multiple sections of <b>466</b> are joined together into a sphere or disk shape by sewing or joining the seams by adhesive bonding. An optional throughhole <b>472</b> can be cut through the sphere or disk shape to allow the sphere or disk-shaped membrane to be attached to the expandable anchor. <figref idref="DRAWINGS">FIG. 65B</figref> is a drawing of a disk-shaped covering for an expandable anchor that is assembled from sheet material into a disk shape. Shape <b>473</b> is cut from a sheet of ePTFE. The two items of <b>473</b> are placed back-to-back. The outer rims of the two pieces of <b>473</b> are joined together by adhesive bonding with a hot melt of FEP or other suitable adhesive or sewing with suture. The two disks <b>473</b> that have been joined together at the outer rim are now inverted or turned inside out to move the seam to the inside of the disks <b>475</b>. <figref idref="DRAWINGS">FIG. 65C</figref> is a drawing of a hemispherical or disk-shaped covering for an expandable anchor that is assembled from a tube and sheet material into a disk shape. Outer shape toroidal tube <b>476</b> is cut from a straight piece of ePTFE tube and formed into a toroid by sewing the tube ends together at <b>477</b>. In various embodiments, an expandable anchor as in <figref idref="DRAWINGS">FIG. 32</figref> is inserted inside the tube <b>476</b> before the two ends of the tube are joined at <b>477</b>. Toroidal tube <b>476</b> is sewn to flat round disk <b>479</b> of ePTFE sheet at <b>478</b>.

0213<figref idref="DRAWINGS">FIG. 66</figref> is a drawing of an expandable anchor with toroidal-shaped anchors <b>480</b> and <b>481</b>, expandable anchor has an Archimedes type screw pump <b>484</b>, drive motor <b>482</b>, battery <b>485</b>, recharging antennae <b>486</b> integrated into the central cylinder <b>488</b> or through a lumen of the device. The Archimedes screw pump can be used as a means to help treat gastroparesis by actively pumping chyme from the stomach to the small intestine (e.g., the duodenum). The entire assembly may be placed into the stomach and intestine using an endoscope and delivering the device through the patient's mouth and stomach to the pylorus. Alternatively some portions of the device may be surgically placed and may not reside entirely within the digestive tract. The pump can also be used in diabetic patients to more precisely control the flow rate of chyme from the stomach to the small intestine. A more constant and controllable flow of chyme will allow the diabetic individual to be able to more accurately control their blood sugar levels. The pump will allow the flow rate of chyme from the stomach to the small intestine to be varied and controlled by the patient.

0214The Archimedes screw <b>484</b> is used to control the flow rate of chyme and/or to pump chyme from the pyloric antrum <b>104</b> into the duodenum <b>112</b>. Battery <b>485</b> powers drive motor <b>482</b>, drive motor <b>482</b> turns drive shaft <b>487</b> and in turn the Archimedes screw <b>484</b> is rotated and chyme enters input side of Archimedes screw <b>483</b> and is pumped through to the output port of pump <b>489</b>. Output port of pump may incorporate a duck bill type anti reflex valve to prevent retrograde flow of chyme. The expandable anchor may be used with or without an intestinal bypass sleeve. The battery <b>485</b> can be remotely charged by inductive charging via the induction coil or antenna <b>486</b>. The control of the motor operation, start stop and rotational speed and direction is control by controller <b>490</b>. Controller <b>490</b> can be remotely controlled and programmed by telemetry. Controller can communicate with a controller via telemetry on the outside of the patients to change the flow rate of chyme. The Archimedes screw may also be driven magnetically by external magnets (outside the patient) and internal magnets on Archimedes screw pump.

0215The flow rate of chyme can be modified depending on the blood glucose levels of the patient. Blood glucose levels can be continuously monitored by a glucose sensor and the insulin infusion rates and chyme flow rates can be controlled by the motor <b>482</b> controlling the Archimedes screw <b>484</b> speed. Currently diabetic patients monitor blood glucose levels and then based on their insulin levels inject themselves with insulin either with a syringe or with an infusion pump. Gastric emptying rates vary depending upon the composition of the food eaten. Sugars pass quickly from the stomach into the small intestine and protein and fats move from the stomach into the small intestine more slowly. Blood sugar control can be difficult to manage if the flow rate of chyme from the stomach to the small intestine is unpredictable and in the case of patients with gastroparesis the chyme flow rate can be very slow to zero. The invention herein disclosed will allow for a tighter glucose level control by allowing more precise control of the flow rate of chyme into small intestine and modulating the flow rate of chyme base on blood glucose levels and insulin infusion rate.

0216<figref idref="DRAWINGS">FIG. 67</figref> is a sectional drawing of a part of the gastrointestinal anatomy, a pyloric antrum <b>104</b>, pylorus <b>106</b>, duodenal bulb <b>107</b> and duodenum <b>112</b>. The expandable anchor of <figref idref="DRAWINGS">FIG. 66</figref> is implanted into the pyloric antrum <b>104</b>, pylorus <b>106</b>, duodenal bulb <b>107</b> and duodenum <b>112</b>.

0217<figref idref="DRAWINGS">FIG. 68</figref> is a cross-sectional drawing of a portion of the digestive tract in a human body. The expandable anchor of <figref idref="DRAWINGS">FIG. 66</figref> is implanted into the pyloric antrum <b>104</b>, pylorus <b>106</b>, duodenal bulb <b>107</b> and duodenum <b>112</b>. A secondary Archimedes screw type pump <b>492</b> is attached to the first pump by means of a flexible drive shaft <b>495</b> and is housed in a hollow flexible cannula <b>491</b> that is attached to the expandable anchor. An optional intestinal bypass sleeve <b>111</b> is attached to the expandable anchor. A blood glucose monitor sensor and an insulin infusion drug pump can monitor and adjust the flow rate of chyme from the stomach to the small intestine by adjusting the speed of the motor driving the Archimedes screw pump.

0218<figref idref="DRAWINGS">FIG. 69A</figref> is an alternative embodiment of an expandable anchor. Expandable anchor is comprised of a ring of beads <b>498</b> with a through hole drilled through the bead <b>500</b>. Beads <b>498</b> are threaded onto a tensioning cable <b>499</b>. Tension on tensioning cable <b>499</b> is maintained by spring <b>497</b>. Ring of beads <b>498</b> can be deformed into noncircular shape for loading the expandable anchor onto a catheter. The tensioning cable elastically recovers ring shape of beads <b>498</b> due to tension exerted by spring on cable. The ring of beads can repeatedly undergo deformation to a non ring shape to a ring shape.

0219<figref idref="DRAWINGS">FIG. 69B</figref> is an alternative embodiment of an expandable anchor. Expandable anchor is comprised of ring of magnets <b>502</b> with a through hole drilled through the magnets <b>500</b>. Magnets <b>498</b> are threaded onto a cable <b>499</b>. Magnets <b>502</b> are loaded onto a tensioning cable <b>503</b> with the magnetic poles alternating in polarity. Ring of magnets maintain separation by magnetic levitation or magnetic repulsion. Magnets <b>502</b> can be deformed into noncircular shape for loading the expandable anchor onto a catheter. The cable and ring of magnets recovers the original ring shape of magnets <b>502</b> due to the force exerted by magnets on each other and the cable. The ring of magnets can repeatedly undergo deformation from a non ring shape to a ring shape.

0220<figref idref="DRAWINGS">FIG. 70A</figref> is drawing of a piece of ePTFE tubing <b>504</b> with a tube <b>505</b> of silicone or latex inserted through the inside diameter of the ePTFE tube <b>504</b>. The ePTFE tube <b>504</b> in the final radially expanded shape can be used for covering an expandable anchor used to anchor an intestinal bypass sleeve. The ePTFE covering for the expandable anchor and the intestinal bypass sleeve can be formed into a single unitary tube in some embodiments disclosed. The ePTFE starting tube <b>504</b> can be made in a uni-axial or a bi-axial orientation. In some embodiments, the final shape is made by radially expanding the ePTFE tube <b>504</b> into the final shape, alternatively the final shape can also be accomplished by wrapping of thin films of ePTFE sheet into the final shape on a mandrel and then laminating them together by sintering the ePTFE layers together with heat or by fusing the ePTFE layers together by using a material such as FEP as a hot melt adhesive. The starting ePTFE tube <b>504</b> can range in size from 3 mm to 12 mm with a wall thickness in the range of 0.003 inch to 0.060 inch. The final expanded diameter of the ePTFE tube can range from the original tube diameter up to 7 times diameter increase from the original tube diameter. The ePTFE tube is plastically deformed during the radial expansion and the diameter largely remains at the new diameter with some diameter lost, 1 to 20 percent due to recoil. The final diameter of the radially stretched ePTFE tube can range from 3 mm to as large as 70 mm. <figref idref="DRAWINGS">FIG. 70B</figref> is a longitudinal cross-section drawing of the ePTFE tube <b>504</b> and silicone tube <b>505</b> shown in <figref idref="DRAWINGS">FIG. 70A</figref>. <figref idref="DRAWINGS">FIG. 70C</figref> is a drawing of a forming mold <b>506</b>. The forming mold <b>506</b> can be made from plastic or metal such as aluminum or stainless steel. The ePTFE tube and silicone tube, <figref idref="DRAWINGS">FIGS. 70A and 70B</figref> will be radially stretched and inflated into the shape of inside of the forming mold <b>506</b>. The radial expansion of the tube of ePTFE was previously disclosed in <figref idref="DRAWINGS">FIG. 64B</figref>. Two disk-shaped apertures <b>507</b> are machined into inside of the forming mold <b>506</b>.

0221<figref idref="DRAWINGS">FIG. 71A</figref> is a drawing of two forming molds <b>506</b> of <figref idref="DRAWINGS">FIG. 70C</figref> that are used to provide an enclosed cavity to limit the expansion of the ePTFE tube <b>504</b> during the blow-molding (radial stretching process). Forming molds <b>506</b> have disk shape apertures <b>507</b> machined into them. The ePTFE tube <b>504</b> with an inner tube of silicone <b>505</b> is place into the forming mold <b>506</b>. <figref idref="DRAWINGS">FIG. 71B</figref> is a drawing of the forming molds <b>506</b> assembled one mold half on top of the other. The ePTFE tube <b>504</b> and silicone tube <b>505</b> are inserted through the central bore between the two forming mold halves <b>506</b>. Central lumen of silicone tube <b>508</b> is open and provides for a pathway to introduce pressurized air or liquid into the lumen of silicone tube. Rigid tube <b>509</b> surrounds ePTFE tube <b>504</b> and silicone tube <b>505</b>. The mold <b>506</b>, ePTFE tube <b>504</b>, silicone tube <b>505</b> can by heated to an elevated temperature (e.g., a temperature of between about 30-150 degrees Celsius) to increase the ultimate elongation of the ePTFE tube <b>504</b> and the silicone tube <b>505</b>. The inside of the silicone tube <b>508</b> is pressurized with air or liquid to radially expand the ePTFE tube <b>504</b> into the shape of the central bore and apertures <b>507</b>. A pressure in the range of 80 psi to 160 psi is typically used to expand the ePTFE tube <b>504</b> and the silicone tube <b>505</b>.

0222<figref idref="DRAWINGS">FIG. 72A</figref> is a drawing of the two forming molds <b>506</b> opened after the ePTFE tube has been blow molded to the shape of the disk-shaped apertures <b>507</b>. The ePTFE tube is now permanently formed into the new final shape <b>510</b>. <figref idref="DRAWINGS">FIG. 72B</figref> is a drawing of the formed ePTFE tube <b>510</b> removed from the mold cavity after the blow-molding/radial stretching process is complete. The ePTFE tube <b>510</b> is now permanently formed into the new final hour glass shape. <figref idref="DRAWINGS">FIG. 72C</figref> is a drawing of the cross-section of the ePTFE tube <b>504</b> and silicone tube <b>505</b> inflated while the two tubes are still in the mold of <b>71</b>B. After the pressure is released the silicone tube <b>505</b> elastically returns to its original starting diameter and the ePTFE tube <b>504</b> partially recoil in diameter but loses only about 10 to 20 percent of the inflated diameter.

0223<figref idref="DRAWINGS">FIG. 73</figref> is a drawing of an alternate embodiment for a shape for the internal cavity for the forming mold <b>511</b> for blow-molding the ePTFE tube. <figref idref="DRAWINGS">FIG. 74</figref> is a drawing of an alternate embodiment for a shape for the internal cavity for the forming mold <b>512</b> for blow-molding the ePTFE tube. <figref idref="DRAWINGS">FIG. 75</figref> is a drawing of an alternate embodiment for a shape for the internal cavity for the forming mold <b>513</b> for blow-molding the ePTFE tube. <figref idref="DRAWINGS">FIG. 76</figref> is a drawing of an alternate embodiment for a shape for the internal cavity for the forming mold <b>514</b> for blow-molding the ePTFE tube.

0224<figref idref="DRAWINGS">FIG. 77A</figref> is a drawing of the shape of the ePTFE tube formed into a double disk shape after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The ends of the radially expanded ePTFE tube shape may be trimmed in length to accomplish the desired final shape. <figref idref="DRAWINGS">FIG. 77B</figref> is a drawing of the shape of the ePTFE tube formed into a double disk shape after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The ends of the radially expanded ePTFE tube shape may be trimmed in length to accomplish the desired final shape. <figref idref="DRAWINGS">FIG. 77C</figref> is a drawing of the shape of the ePTFE tube formed into a double cup shape after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The ends of the radially expanded ePTFE tube shape may be trimmed in length to accomplish the desired final shape. <figref idref="DRAWINGS">FIG. 77D</figref> is a drawing of the shape of the ePTFE tube formed into a disk and cup shape after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The ends of the radially expanded ePTFE tube shape may be trimmed in length to accomplish the desired final shape. <figref idref="DRAWINGS">FIG. 77E</figref> is a drawing of the shape of the ePTFE tube formed into a double spherical shape after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The ends of the radially expanded ePTFE tube shape may be trimmed in length to accomplish the desired final shape.

0225<figref idref="DRAWINGS">FIG. 78A</figref> is a drawing of the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The anchor covering portion <b>515</b> of the sleeve and the intestinal bypass <b>516</b> sleeve are formed integrally into one sleeve. The length <b>517</b> of the intestinal bypass sleeve <b>516</b> may range from a few inches up to 4 feet or more. The sleeve may include an optional bulbous shape <b>518</b> for the duodenal bulb. The intestinal bypass sleeve length <b>517</b> can range from a few inches to 4 feet or more. <figref idref="DRAWINGS">FIG. 78B</figref> is a drawing of the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The anchor covering portion <b>515</b> of the sleeve and the intestinal bypass sleeve <b>516</b> are formed integrally into one sleeve. The small diameter end of the tube <b>519</b> is started to be inverted inside to pull it inside to form an interior tube layer for the expandable anchor. <figref idref="DRAWINGS">FIG. 78C</figref> is a drawing of the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The anchor covering portion of the sleeve <b>515</b> and the intestinal bypass sleeve <b>516</b> are formed integrally into one sleeve. The small diameter end of the tube is fully inverted inside forming an interior layer <b>521</b> for the expandable anchor. Two pockets <b>520</b> are formed with the sleeve, an expandable anchor as previously disclosed in this patent application may be placed within the pockets.

0226<figref idref="DRAWINGS">FIG. 79A</figref> is a drawing of an alternative embodiment of the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The anchor covering portion of the sleeve <b>523</b> and the intestinal bypass sleeve <b>522</b> are formed integrally into one sleeve. <figref idref="DRAWINGS">FIG. 79B</figref> is a drawing of an alternative embodiment of the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The anchor covering portion of the sleeve <b>524</b> and the intestinal bypass sleeve <b>522</b> are formed integrally into one sleeve. The end of the tube <b>527</b> is started to be inverted inside to pull it inside to form an interior tube layer for the expandable anchor. <figref idref="DRAWINGS">FIG. 79C</figref> is a drawing of an alternative embodiment of the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The anchor covering portion of the sleeve <b>528</b> and the intestinal bypass sleeve <b>522</b> are formed integrally into one sleeve. The end of the tube <b>527</b> is fully inverted inside forming an interior layer <b>526</b> for the expandable anchor which can be located in pockets <b>525</b>.

0227<figref idref="DRAWINGS">FIG. 80A</figref> is a drawing of an alternative embodiment of the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The anchor covering portion of the sleeve <b>530</b> and the intestinal bypass sleeve <b>529</b> are formed integrally into one sleeve. The end of the tube <b>531</b> is started to be inverted inside to pull it inside to form an interior tube layer for the expandable anchor. <figref idref="DRAWINGS">FIG. 80B</figref> is a drawing of an alternative embodiment of the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The anchor covering portion of the sleeve <b>530</b> and the intestinal bypass sleeve <b>529</b> are formed integrally into one sleeve. The small diameter end of the tube is fully inverted inside to pull it inside to form an interior tube layer <b>532</b> for an expandable anchor as previously disclosed.

0228<figref idref="DRAWINGS">FIG. 81A</figref> is a drawing of an alternative embodiment of the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The anchor covering portion of the sleeve <b>534</b> and the intestinal bypass sleeve <b>533</b> are formed integrally into one sleeve. <figref idref="DRAWINGS">FIG. 81B</figref> is a drawing of an alternative embodiment of the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The anchor covering portion of the sleeve <b>535</b> and the intestinal bypass sleeve <b>533</b> are formed integrally into one sleeve. The end of the tube <b>537</b> is started to be inverted inside to pull it inside to form an interior tube layer for the expandable anchor. <figref idref="DRAWINGS">FIG. 81C</figref> is a drawing of an alternative embodiment of the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The anchor covering portion of the sleeve <b>538</b> and the intestinal bypass sleeve <b>533</b> are formed integrally into one sleeve. The end of the tube is fully inverted inside forming an interior layer <b>536</b> for the expandable anchor. The end of the tube is fully inverted inside to pull it inside to form an interior tube layer <b>532</b> for an expandable anchor as previously disclosed. An expandable anchor may be place in between the layers at <b>539</b>.

0229<figref idref="DRAWINGS">FIG. 82A</figref> is a drawing of an alternative embodiment of the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The anchor covering portion of the sleeve <b>541</b> and the intestinal bypass sleeve <b>540</b> are formed integrally into one sleeve. The small diameter end of the tube is inverted inside to pull it inside to form an interior tube layer for the expandable anchor. The interior tube is formed into the shape of anti-reflux valve <b>542</b>. The anti reflux valve <b>542</b> may be formed of two leaflets <b>545</b>, three leaflets <b>546</b>, or four leaflets <b>547</b>. <figref idref="DRAWINGS">FIG. 82B</figref> is a drawing of an alternative embodiment of the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The anchor covering portion of the sleeve <b>541</b> and the intestinal bypass sleeve <b>540</b> are formed integrally into one sleeve. The small diameter end of the tube is inverted inside to pull it inside to form an interior tube layer for the expandable anchor. The interior tube is formed into the shape of a restrictive stoma <b>543</b>. <figref idref="DRAWINGS">FIG. 82C</figref> is a drawing of an alternative embodiment of the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The anchor covering portion of the sleeve and the intestinal bypass sleeve are formed integrally into one sleeve. The small diameter end of the tube is inverted inside to pull it inside to form an interior tube layer for the expandable anchor. The interior tube is formed into the shape of a restrictive stoma and then an anti-reflux valve in series <b>544</b>.

0230<figref idref="DRAWINGS">FIG. 83A</figref> is a drawing of an alternative embodiment of the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The anchor covering portion of the sleeve <b>548</b> and the intestinal bypass sleeve <b>549</b> are formed separately and bonded together. Intestinal bypass sleeve <b>549</b> may be formed from FEP or other suitable polymer. <figref idref="DRAWINGS">FIG. 83B</figref> is a drawing of an alternative embodiment of the final formed shape of the ePTFE tube after blow-molding/radial stretching of the original cylindrical tube of ePTFE. The anchor covering portion of the sleeve <b>550</b> and the intestinal bypass <b>551</b> sleeve are formed integrally into one sleeve. The small diameter end of the tube is inverted inside to pull it inside to form an interior tube layer for the expandable anchor. The intestinal bypass sleeve <b>551</b> has annular rings or corrugations formed into it to allow for the sleeve to bend easier without kinking and to provide for more longitudinal elasticity.

0231<figref idref="DRAWINGS">FIG. 84</figref> is a drawing of an alternative embodiment of the invention previously disclosed in <figref idref="DRAWINGS">FIG. 46</figref>. The expandable anchor is comprised of a hollow tubular braided structure of wire. The wire form has been heat set or shaped to conform to the shape of the pylorus and the duodenal bulb. Optional barbs and/or hooks <b>552</b> that have been incorporated into the anchor to provide for additional tissue penetration and additional anchoring. <figref idref="DRAWINGS">FIG. 85</figref> is a drawing of an expandable anchor. The expandable anchor incorporates optional barbs and/or hooks <b>553</b> have been incorporated into the anchor to provide for tissue penetration and additional anchoring. The barbs are outwardly oriented to engage the tissue of the pyloric antrum, pylorus and/or duodenal bulb. In various embodiments, the barbs extend outwardly in a direction generally perpendicular to the longitudinal axis. According to other embodiments, the barbs extend at an angle with respect to the longitudinal axis of anywhere between about 0 and about 90 degrees. The lengths of the barbs may range from less than 1 mm up to several mm in length. The barbs may be constructed from Nitinol, titanium, Elgiloy, MP35N, stainless steel, platinum, platinum iridium, plastics or other suitable materials. The design and construction of the expandable anchor is similar to what was previously disclosed in <figref idref="DRAWINGS">FIG. 6</figref>.

0232<figref idref="DRAWINGS">FIG. 86</figref> is a drawing of an expandable anchor. The expandable anchor incorporates optional barbs and/or hooks <b>554</b> that have been incorporated into the anchor to provide for tissue penetration and additional anchoring. The design and construction of the expandable anchor is similar to what was previously disclosed in <figref idref="DRAWINGS">FIG. 6</figref>. <figref idref="DRAWINGS">FIG. 87</figref> is a drawing of an expandable anchor. The expandable anchor incorporates optional barbs and/or hooks <b>555</b> that have been incorporated into the anchor to provide for tissue penetration and additional anchoring. The design and construction of the expandable anchor is similar to what was previously disclosed in <figref idref="DRAWINGS">FIG. 18</figref>. <figref idref="DRAWINGS">FIG. 88</figref> is a drawing of an expandable anchor. The expandable anchor incorporates optional barbs and/or hooks <b>556</b> that have been incorporated into the anchor to provide for tissue penetration and additional anchoring. In various embodiments, the barbs extend outwardly in a direction generally perpendicular to the longitudinal axis. According to other embodiments, the barbs extend at an angle with respect to the longitudinal axis of anywhere between about 0 and about 90 degrees. The design and construction of the expandable anchor is similar to what was previously disclosed in <figref idref="DRAWINGS">FIG. 20</figref>. <figref idref="DRAWINGS">FIG. 89</figref> is a drawing of an expandable anchor in which the expandable anchor's antral disk <b>557</b> is larger in diameter than the duodenal bulb disk <b>558</b>. The design and construction of the expandable anchor is similar to what was previously disclosed in <figref idref="DRAWINGS">FIG. 18</figref>.

0233<figref idref="DRAWINGS">FIG. 90</figref> is a drawing of an expandable anchor. The expandable anchor has a central cylinder <b>559</b> as previously disclosed in <figref idref="DRAWINGS">FIG. 38</figref>. The expandable anchor has an antral disk <b>560</b> comprised of Nitinol wire in a braided form and a duodenal disk <b>561</b> comprised of Nitinol wire in a braided form. The Nitinol braid can be comprised of a single layer of braid or it may be double back on itself and the cut wire ends of the braid may be attached to the central cylinder at location <b>589</b>. The Nitinol wire braid may be shape set or formed into the desired shape by the means previously disclosed in this application.

0234<figref idref="DRAWINGS">FIG. 91</figref> is a drawing of an anti-reflux valve for an expandable anchor. The anti-reflux valve <b>562</b> can be located within the central cylinder as previously disclosed as item <b>346</b> in <figref idref="DRAWINGS">FIG. 40</figref>. The anti-reflux valve <b>562</b> may be made from a thin-walled tube of polymer such as ePTFE, PTFE, FEP, silicone, polyurethane, polyethylene or other suitable polymer. The polymer may be designed with the proper thickness and mechanical properties to allow the valve to self seal or close when retrograde flow is exerted on the valve. The anti-reflux valve may be bonded to the central cylinder <b>565</b>. Anti-reflux valve is in an open position <b>566</b> when chyme flows from the stomach to the duodenum and in a closed position <b>563</b> and <b>564</b> when chyme flows in a retrograde direction from the duodenum to the stomach. The anti-reflux valve can allow chyme to flow from the stomach to the duodenum without being restricted, but it can also limit or prevent retrograde flow from the duodenum to the antrum. Retrograde flow from the duodenum to the pylorus can be undesirable and cause eversion of the intestinal bypass sleeve and allow the sleeve to evert through the expandable anchor into the stomach. The anti-reflux valve <b>562</b> can be designed to evert and allow retrograde flows at very high pressures such as during vomiting. The inside diameter of the anti-reflux valve in the open state can range from 4 mm to 18 mm in diameter.

0235<figref idref="DRAWINGS">FIG. 92</figref> is a drawing of an anti-reflux valve for an expandable anchor. The anti-reflux valve <b>568</b> can be located within the central cylinder as previously disclosed as item <b>346</b> in <figref idref="DRAWINGS">FIG. 40</figref>. The anti-reflux valve <b>568</b> may be made from a thin-walled tube of polymer such as ePTFE, PTFE, FEP, silicone, polyurethane, polyethylene or other suitable polymer. The anti-reflux valve may be bonded to the central cylinder <b>567</b>. Anti-reflux valve <b>568</b> can have a rigid ring <b>571</b> bonded onto the end of the tube to prevent the anti-reflux valve <b>568</b> from being everted through the central cylinder at high pressures. Anti-reflux valve is in an open position <b>571</b> when chyme flows from the stomach to the duodenum and in a closed position <b>569</b> when chyme flows in a retrograde direction from the duodenum to the stomach. The anti-reflux valve can allow chyme to flow from the stomach to the duodenum without being restricted, but it can also limit or prevent retrograde flow from the duodenum to the antrum. Retrograde flow from the duodenum to the pylorus can be undesirable and cause eversion of the intestinal bypass sleeve and allow the sleeve to evert through the expandable anchor into the stomach.

0236<figref idref="DRAWINGS">FIG. 93</figref> is a drawing alternative embodiment of an anti-reflux valve for an expandable anchor. The anti-reflux valve <b>573</b> can be located within the central cylinder as previously disclosed as item <b>346</b> in <figref idref="DRAWINGS">FIG. 40</figref>. The anti-reflux valve <b>573</b> may be made from a thin-walled tube of polymer such as ePTFE, PTFE, FEP, silicone, polyurethane, polyethylene or other suitable polymer. The tube can be constructed of one extrusion of tubing or it may be made from three individual sections or leaflets joined to form the circumference of the valve. The anti-reflux valve <b>573</b> may be bonded to the central cylinder <b>572</b>. The polymer tube for the anti-reflux valve <b>573</b> can be attached to the metal flexing post <b>577</b>. The anti-reflux valve has three flexing posts <b>577</b> at a spacing of about 120 degrees around the circumference of the valve. The polymer tube can be attached to the flexing posts by sewing, gluing or other mechanical means. The flexing posts <b>577</b> can be made from metals such as Titanium, Nitinol, stainless steel, elgiloy, MP35N, or plastics such as PEEK or delrin or other suitable material. The flexing posts <b>577</b> allows the valve to open at low pressures, but holds the valve leaflets so that they do not evert back into the lumen of the central cylinder <b>572</b>. Anti-reflux valve is in an open position <b>574</b> when chyme flows from the stomach to the duodenum and in a partially closed position <b>575</b> and fully closed position <b>576</b> when chyme flows in a retrograde direction from the duodenum to the stomach. The anti-reflux valve <b>573</b> can allow chyme to flow from the stomach to the duodenum without being restricted, but it can also limit or prevent retrograde flow from the duodenum to the antrum. The inside diameter of the anti-reflux valve in the open state can range from 4 mm to 18 mm in diameter.

0237<figref idref="DRAWINGS">FIG. 94</figref> is a drawing of an alternative embodiment of an anti-reflux valve for an expandable anchor. The anti-reflux valve <b>582</b> can be located within the central cylinder as previously disclosed as item <b>346</b> in <figref idref="DRAWINGS">FIG. 40</figref>. The anti-reflux valve <b>582</b> can be made from a thin-walled tube of polymer such as ePTFE, PTFE, FEP, silicone, polyurethane, polyethylene or other suitable polymer. The tube can be constructed of one extrusion of tubing or it may be made from two individual sections or leaflets joined to form the circumference of the valve. The anti-reflux valve <b>582</b> may be bonded to the central cylinder <b>578</b>. The polymer tube for the anti-reflux valve <b>582</b> can be attached to the metal flexing posts <b>579</b>. The anti-reflux valve has two flexing posts <b>579</b> at a spacing of about 180 degrees around the circumference of the valve. The polymer tube can be attached to the flexing posts by sewing, gluing or other mechanical means. The flexing posts <b>579</b> can be made from metals such as Titanium, Nitinol, stainless steel, elgiloy, MP35N, or plastics such as PEEK or delrin or other suitable material. The space <b>583</b> between the flexing posts can be adjusted to increase the pretension on the leaflets and affect the opening pressure of the anti-reflux valve. If the post spacing <b>583</b> is increased the leaflets will be under greater tension and the valve opening pressure will be increased. The flexing posts <b>579</b> can be designed to allow the valve to open at low pressures, but the posts still hold the valve leaflets so that the leaflets do not evert back into the lumen of the central cylinder <b>578</b>. Anti-reflux valve is in an open position <b>580</b> when chyme flows from the stomach to the duodenum and in closed position <b>581</b> when chyme flows in a retrograde direction from the duodenum to the stomach. The opening pressure of the anti-reflux valve can be designed to be close to zero if little to no flow resistance is desired to the flow of chime from the stomach to the duodenum. To induce additional weight loss in a patient or if a dumping syndrome occurs it may be desirable to have the anti-reflux valve that has a moderate flow resistance in an anti-grade flow direction. The post stiffness or post spacing <b>583</b> can be adjusted to customize the desired flow resistance in the antegrade direction while still maintaining the anti-reflux properties of the valve. Thus the anti-reflux valve <b>582</b> can be designed to accomplish multiple different functions: provide for an anti-reflux function, valve opens at low pressures in an antegrade flow direction, or valve opens at a higher pressure in the antegrade flow direction. Previous prior art flow limiters consisted of orifice type valves. This provides for a flow limiter that can open easily to a larger diameter to allow large food particles to pass through the valve without the stretching of a polymer orifice and still provide the desired flow resistance. Thus this design provides for a flow limiter without the inherent risk of having the orifice become obstructed with large particles of chyme. The inside diameter of the anti-reflux valve in the open state can range from 4 mm to 18 mm in diameter.

0238<figref idref="DRAWINGS">FIG. 95</figref> is a drawing of an alternative embodiment of an anti-reflux valve frame with flexing posts. The frame is constructed so the flexing posts <b>585</b> are integrated into the wall of the central cylinder <b>584</b>. <figref idref="DRAWINGS">FIG. 96</figref> is a drawing of an alternative embodiment of an anti-reflux valve frame with flexing posts. The flexing posts can be designed to have holes in the posts <b>588</b> or a slot <b>587</b> to provide for a means to mechanically attach the leaflets to the flexing posts.