Anchorless intragastric Device For Treating Obesity
A intragastric device that contains a compressible free-floating structure and a sleeve attached thereto is provided. The device is considered to be anchorless as the sleeve is not physically attached to any portion of the GI tract. The device is configurable between a compressed pre-deployment configuration and an expanded post-deployment configuration. The free-floating device may be composed of a shape memory material such a nitinol. In some embodiments, the free-floating structure is space occupying and non-porous. The sleeve may be attached to the free-floating structure, such as with sutures and/or glue. In some embodiments, a stent may be inserted at the proximal end of the sleeve. A second free-floating structure may be connected to the free-floating structure such that there is an upper structure and a lower structure. In some embodiments, the gastrointestinal device is used to deliver prebiotic and/or probiotic therapy to a patient.
This application is a continuation of U.S. patent application Ser. No. 15/496,625, filed Apr. 25, 2017, which claims the benefit of U.S. Provisional Application 62/328,326, filed Apr. 27, 2016, both of which are incorporated herein by reference in their entireties for all purposes.
FIELDThe present specification relates generally to medical devices useful in the treatment of obesity. More particularly, the present specification relates to intragastric and gastrointestinal devices of dynamic weight that reduce gastric volume, slow gastric emptying, and/or bypass portions of the small intestine, thereby leading to patient weight loss.
BACKGROUNDObesity is a common condition and growing public health problem in developed nations including the United States. As of 2009, more than two thirds of American adults, approximately 127 million people, were either overweight or obese. Over one third of American adults are obese. Data suggest that 300,000 Americans die prematurely from obesity-related complications each year. Many children in the United States are also either overweight or obese. Hence, the overall number of overweight Americans is expected to rise in the future. It has been estimated that obesity costs the United States over $100 billion annually in direct and indirect health care expenses and in lost productivity. This trend is also apparent in many other developed nations.
For adults, the body mass index (BMI) is used to determine if one is overweight or obese. A person's BMI is calculated by multiplying body weight in pounds by 703 and then dividing the total by height in inches squared. A person's BMI is expressed as kilograms per meter squared. An adult is considered overweight if his or her BMI is between 25 and 30 kg/m2. Obesity is defined as possessing a BMI between 30 and 40 kg/m2. A BMI greater than 30 kg/m2 is associated with significant co-morbidities. Morbid obesity is defined as possessing either a body weight more than 100 pounds greater than ideal or a BMI greater than 40 kg/m2. Approximately 5% of the U.S. population meets at least one of the criteria for morbid obesity. Morbid obesity is associated with many diseases and disorders including, for example: diabetes; hypertension; heart attack; stroke; dyslipidemia; sleep apnea; pickwickian syndrome;
asthma; lower back and disc disease; weight-bearing osteoarthritis of the hips, knees, ankles and feet; thrombophlebitis and pulmonary emboli; intertriginous dermatitis; urinary stress incontinence; gastroesophageal reflux disease (GERD); gallstones; and, sclerosis and carcinoma of the liver. In women, infertility, cancer of the uterus, and cancer of the breast are additionally associated with morbid obesity. Taken together, the diseases associated with morbid obesity markedly reduce the odds of attaining an average lifespan. The sequelae raise annual mortality rates in affected people by a factor of 10 or more.
Current treatments for obesity include diet, exercise, behavioral treatments, medications, surgery (open and laparoscopic), and endoscopic devices. New drug treatments for obesity are currently being evaluated in clinical trials. However, a high efficacy pharmaceutical treatment has not yet been developed. Further, short-term and long-term side effects of current pharmaceutical treatments often concern consumers, pharmaceutical providers, and/or their insurers. Generally, diet or drug therapy programs have been consistently disappointing, failing to bring about significant, sustained weight loss in the majority of morbidly obese people.
Currently, most operations used to treat morbid obesity include gastric restrictive procedures, involving the creation of a small (e.g., 15-35 ml) upper gastric pouch that drains through a small outlet (e.g., 0.75-1.2 cm), setting in motion the body's satiety mechanism. About 15% of operations used to treat morbid obesity performed in the
United States involve combining a gastric restrictive procedure with a malabsorptive procedure. Typical malabsorptive procedures divide small intestinal flow into a biliary-pancreatic conduit and a food conduit. Potential long-term side effects associated with abdominal surgical procedures include herniation and small bowel obstruction. In addition, long-term problems specific to bariatric procedures also include gastric outlet obstruction, marginal ulceration, protein malnutrition, and vitamin deficiency.
Other surgical strategies for treating obesity include endoscopic procedures, many of which are still in development. Endoscopic procedures and devices to produce gastric pouch and gastrojejunal anastomosis are used to replicate laparoscopic procedures. Endoscopically placed gastric balloons restrict gastric volume and result in satiety with smaller meals. For example, U.S. patent application Ser. No. 10/221,562, now issued as U.S. Pat. No. 7,172,613 and assigned to Districlass Medical SA, describes an “intragastric device inserted by endoscopic path into a patient's stomach. The device includes a balloon or envelope having a specific nominal volume. The balloon is sealingly connected to connecting elements consisting of a disc forming a support base for the balloon against an inner wall of the stomach. The device also includes a flexible tube or catheter for connecting the balloon to a filling device and catching element integral with the tube or catheter. The connection elements enable a doctor to set and/or remove the balloon and to fix, either inside the patient's body, or subcutaneously the filling device and to be able to bring the balloon or envelope to its predetermined nominal volume.”
The silicone intragastric balloon (IGB) has been developed as a temporary aid to achieve weight loss specifically for people who weigh 40% or more of their ideal weight and who have had unsatisfactory results in their treatment of obesity, despite being cared for by a multidisciplinary team. This treatment is also indicated for morbidly obese patients who have a high morbidity and mortality risk for surgery. The placement and removal of the IGB is an endoscopic procedure and the balloon is designed to float freely inside the stomach. The IGB technique reduces the volume of the stomach and leads to a premature feeling of satiety. However, use of IGBs did not show convincing evidence of a greater weight loss. The relative risks for minor complications, for example, gastric ulcers and erosions, were significantly raised. All inflatable IGB devices suffer from the problem of deterioration of the balloon over time. This deterioration can result in deflation with loss of efficacy and complications such as small bowel obstruction secondary to balloon migration. Due to loss of efficacy overtime, IGB devices are recommended only for short (<6 month) durations. In addition, rapid inflation of the balloon poses the risk of esophageal or gastric perforations, both of which are surgical emergencies. Deaths have been reported in patients using IGB treatment.
Endoscopic procedures are also used to deploy mesh structures into the stomach in an effort to occupy stomach volume and create the artificial sensation of being full. For example, U.S. patent application Ser. No. 11/657,231, assigned to Wilson-Cook Medical, Inc., describes an “intragastric device generally compris[ing] a strip digestive-resistant mesh material that is operable between a first configuration and a second configuration. The first configuration is sufficiently small to permit introduction of the digestive-resistant mesh material into a gastric lumen of the mammal. The second configuration is sufficiently large to prevent the digestive-resistant mesh material from passing through the mammal's pylorus, thereby permitting the mesh member to act as an artificial bezoar.”
Although endoscopically placed balloon structures can be effective, they are not without their associated risks and complications. Mesh structures are effective in occupying available gastric volume but they do not address gastric emptying. Migration and small bowel obstruction from such devices continue to remain a significant problem. Therefore, a need exists for an intragastric device to treat obesity that combines the benefits obtained through reducing stomach volume, slowing gastric emptying, and providing a bypass for food past the pylorus and a portion of the small intestine, while remaining relatively safe. The device should also include a component for preventing migration of the entire device out of the stomach. This device should limit side effects and be able to be deployed and removed in a non-invasive manner with relative ease. In addition, this device should have the option of further treating obesity by including the benefits obtained by malabsorptive diversion procedures. The addition of this optional benefit would make the device effective in treating not only obesity, but type II diabetes as well.
Typical metal structures cannot survive the hostile environment, particularly with respect to the high acidity, of the stomach. Intragastric devices comprising acid-sensitive components, such as metal wires, are typically covered or coated in an acid-resistant material (i.e. silicone) to prevent degradation of these components by acidic gastric contents. Conventional manufacturing processes for creating these coated intragastric devices first coat the metal wires of the device and then form the wires into the desired end shape of the device. As the shapes and structures of intragastric devices become more complicated, these conventional processes are unable to properly create the desired end product. A shape memory metal, such as Nitinol, is heat-set at temperatures in excess of 400° C. Coating the metal with an acid-resistant material and then heat-setting into the final shape would result in destruction of the coating during exposure to the high temperatures. Therefore, a method of manufacture is needed wherein the wires of the intragastric device are first formed into the desired end shape and are then coated with a corrosion-resistant material. Such a method will take care to prevent the coating and covering or clogging of the spaces or openings between the wires of the wire mesh. Such a method will also produce a finished device that is still flexible enough to be converted from a compressed, first pre-deployment shape to an expanded, post-deployment shape.
Specific surgical options for the treatment of obesity also include laparoscopic sleeve gastrectomy (LSG) and laparoscopic roux-en-y-gastric bypass (RGB) surgery. Gastrectomy refers to a partial or full surgical removal of the stomach. LSG is a restrictive treatment, surgical weight-loss procedure in which the stomach is reduced to approximately 25% of its original size by surgical removal of a large portion following the major curve. The open edges are then attached together (often with surgical staples) to form a sleeve or tube with a banana shape. The procedure permanently reduces the size of the stomach. The procedure is performed laparoscopically and is not reversible. Following the operation, the stomach empties its contents rapidly into the small intestine, but with little or no vomiting (characteristic of other restrictive procedures).
LSG involves a longitudinal resection of the stomach on the greater curvature from the antrum starting opposite the nerve of Latarjet up to the angle of His. The first step of the procedure is the division of the vascular supply of the greater curvature of the stomach which is achieved with the section of the gastro-colic and gastro-splenic ligaments close to the stomach. The greater curvature is completely freed up to the left crus of the diaphragm to resect the gastric fundus that harbors the ghrelin secreting cells of the stomach. The second step of the procedure is the longitudinal gastrectomy that “sleeves” the stomach to reduce its shape to a narrow tube. The pylorus and part of the antrum are preserved, resulting in a lesser curvature-based “restrictive” gastric sleeve.
Sleeve gastrectomy (also called gastric sleeve) is usually performed on extremely obese patients, with a body mass index of 40 or more, where the risk of performing a gastric bypass or duodenal switch procedure may be too large. A two-stage procedure is performed: the first is a sleeve gastrectomy; the second is a conversion into a gastric bypass or duodenal switch. Patients usually lose a large quantity of their excess weight after the first sleeve gastrectomy procedure but, if weight loss ceases, the second step is performed.
For patients that are obese but not extremely obese, sleeve gastrectomy alone is a suitable operation with minimal risks. Sleeve gastrectomy is currently an acceptable weight loss surgery option for obese patients as a single procedure. Most surgeons prefer to use a bougie (tapering cylindrical instrument) having an outer diameter between 32-60 French (the optimal bougie size is 32 Fr-36 Fr) with the procedure. The ideal approximate remaining capacity of the stomach after the procedure is 15 ml.
One of the mechanisms involved in weight loss observed after the LSG is the dramatic reduction of the capacity of the stomach. The concept of restriction has been widely used in bariatric surgery in vertical banded gastroplasty (VBG) and laparoscopic adjustable gastric banding (LAGB). The distension of the small gastric pouch in the LAGB procedure or VBG is intended to account for the feeling of early fullness, enhanced satiety and decreased hunger experienced by a patient after the ingestion of small quantities of food.
The hormonal modifications induced by LSG differ from those found after a purely restrictive procedure such as LAGB. Ghrelin, a peptide hormone mainly produced in the fundus of the stomach, is believed to be involved in the mechanisms regulating hunger. There is a significant reduction in ghrelin associated with resection of the gastric fundus.
What makes LSG a preferable option lies in the fact that the operation is a straightforward procedure that can generally be completed laparoscopically, even in the case of an extremely obese patient. It does not involve any digestive anastomosis and no mesenteric defects are created, eliminating the risk of internal hernia. In addition, no foreign material is used as in the case of gastric banding, the whole digestive tract remains accessible to endoscopy, and it is not associated with Dumping syndrome. Also, the risk of peptic ulcer is low and the absorption of nutrients, vitamins, minerals and drugs is not altered.
Early reports of LSG have shown it to be safe and effective with marked weight loss and significant reduction of major obesity-related comorbidities. The question whether LSG may work as a sole bariatric procedure in the long term cannot yet be answered. For this reason, LSG is proposed as the first step of a staged approach in patients for whom a biliopancreatic diversion with duodenal switch (BPD-DS) or RGB seems too hazardous because of a very high BMI (super obesity=BMI>50 or super-super obesity=BMI>60) and/or associated diseases whether related or not to obesity.
Laparoscopic roux-en-y-gastric bypass (RGB) involves the creation of a small (20-30 m I) gastric pouch and a Roux limb (typically 75-105 cm) that reroutes a portion of the alimentary tract to bypass the distal stomach and proximal small bowel. Following RGB, a pleiotropic endocrine response may contribute to improved glycemic control, appetite reduction, and long-term changes in body weight. RGB also has a profoundly positive impact on obesity-related comorbidities and quality of life. Other advantages include established long-term effectiveness for sustained weight loss, reduction of comorbidities, minimal risk for long-term nutritional sequelae, and effective relief of gastroesophageal reflux disease (GERD). RGB is not without risks. Common causes of death include pulmonary embolism and anastomotic leaks. Nonfatal perioperative complications include anastomotic leaks, venous thromboembolism, wound infections, small bowel obstruction, and bleeding. Postoperative gastrointestinal complications include nausea and vomiting, micronutrient deficiencies, and possible weight regain.
Failures after these bariatric procedures are common and patients start regaining weight or the progressive weight loss stops at a sub-therapeutic level. Therefore, there is a need for salvage therapy after one or more failed bariatric procedures. What is needed is a device to be used following bariatric surgery that will combine the benefits of gastric volume reduction, bilio-pancreatic diversion and/or intestinal bypass to enhance the weight loss effects of the device. What is also needed is a device that will further reduce the volume of a surgically restricted stomach to reduce the amount of calories that can be consumed. The device will also bypass the proximal small intestine or the roux limb of the intestine in order to produce intestinal mal absorption, bilio-pancreatic diversion or both. The device can further act to delay gastric emptying, release the gastric hormones associated with satiety, and stimulate the gastric nerves associated with sensation of satiety. The device could be combined with other therapeutic agents such as electrical stimulation, magnetic stimulation, or pharmaceutical agents.
The device can be used as a primary therapeutic procedure for weight loss or as a bridge to surgery for a definitive weight loss procedure. The device may also be used in the treatment of other conditions including, but not limited to, metabolic syndrome, diabetes mellitus, dyslipidemias and cardiovascular disease.
SUMMARYThe present specification discloses an intragastric device for treating obesity comprising: a compressible component having a pre-deployment configuration and a post-deployment configuration and adapted to be positioned and free-floating within a stomach of a patient when in said post-deployment configuration; and a sleeve having a proximal end, a distal end, and a lumen within wherein said sleeve is attached at its proximal end to a distal end of said compressible component and extends through a pylorus of said patient such that said distal end of said sleeve is positioned within a mid-duodenum of said patient, further wherein said sleeve is configured to transit food from said stomach of said patient to said mid-duodenum such that said food bypasses said pylorus and a proximal duodenum of said patient; wherein said compressible component is configured to occupy space in said stomach and provide positioning support to said sleeve such that said sleeve does not migrate in a distal direction into a patient's jejunum or more than 5 cm in a proximal direction in said stomach, further wherein said compressible component does not include food sequestering or delayed gastric emptying properties.
The intragastric device may be configured to be delivered by a catheter.
Optionally, the compressible component is composed of a shape memory metal. The shape memory metal may be Nitinol. Optionally, the intragastric device further comprises a non-porous balloon positioned over said shape memory metal and configured to reduce the exposure of said shape memory metal to gastric acid. The balloon may be inflatable with air, water, and saline. The intragastric device may be configured to have a functional life of at least one year wherein functional life is defined as a time period before said shape memory metal begins to degrade as a result of expose to gastric acid. The balloon may be sutured to said compressible component.
Optionally, the intragastric device further comprises a stent positioned between said compressible component and said sleeve and configured to be positioned in said pylorus.
The compressible component may have a shape comprising any one of a balloon, double balloon, ball, parachute, inverted parachute, disc, double disc, horseshoe, flower, teardrop, double teardrop, cylinder, inverted square pyramid, funnel, bobbin, lotus, wine glass, or orange peel.
The sleeve may have a shape comprising any one of a cylinder or funnel.
Optionally, the compressible component and the sleeve are not physically attached at any point to a patient's anatomy.
Optionally, the compressible component and the sleeve are configured to be atraumatic to the patient's anatomy.
The compressible component may be configured to apply pressure to said stomach to induce a feeling of fullness or satiety in said patient.
Optionally, the intragastric device further comprises a second compressible component attached to a proximal end of said compressible component configured to occupy additional stomach space and provide additional pressure to said stomach.
Optionally, the compressible component further comprises a collar at its distal end configured to assist in positioning said sleeve.
The present specification also discloses a gastrointestinal device for treating obesity comprising a three-dimensional porous structure configurable between a compressed pre-deployment configuration to facilitate delivery and an expanded post-deployment configuration. The porous structure includes a first opening at its proximal end and a larger second opening at its distal end. The porous structure also includes a sleeve coupled to its distal end. Optionally, the device further includes a suture at the proximal end of the wire mesh structure to facilitate retrieval and an anti-migration component positioned at the junction of the porous structure with the sleeve. The porous structure is deployed in a patient's stomach such that the anti-migration component sits proximal to the patient's pylorus and prevents migration of the entirety of the device into and through the pylorus. The sleeve extends through the pylorus, into the duodenum and ends in the duodenum or jejunum. Food enters the device from the first opening at the proximal end of the porous structure, passes through the porous structure and sleeve, and exits at the distal end of the sleeve. The device treats obesity by providing a relatively immovable volume occupying structure in the stomach and a bypass for food past the pylorus and proximal portion of the small intestine. Optionally, the device further acts to slow the passage of food through the digestive tract. Patients with the device experience satiety more quickly and have a prolonged sensation of satiety. Optionally, the device is anchorless and atraumatic. Optionally, the intragastric device is used to deliver prebiotic and/or probiotic therapy to the patient.
The aforementioned and other embodiments of the present invention shall be described in greater depth in the drawings and detailed description provided below.
These and other features and advantages of the present invention will be appreciated as they become better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein:
In one embodiment, the present specification is directed toward an intragastric device of dynamic weight used in obese patients to induce weight loss. In various embodiments, the intragastric device comprises a porous three dimensional structure having a pre-deployment shape and a post-deployment shape. In one embodiment, the porous three dimensional structure is a non-inflatable wire mesh structure, or a spiral structure made of shape memory metal or shape memory polymer that changes from a pre-deployment compressed cylindrical shape to a post-deployment sphere, oval, kidney bean or any predefined shape of significant volume. In another embodiment, the intragastric device is made of a plastic material or a polymer such as polyether ether ketone (PEEK) or polyester or a bioresorbable material. The device changes back and forth from the pre-deployment to post-deployment shape by minimal mechanical force and/or temperature changes arising from the room temperature pre-deployment shape to the body temperature post-deployment shape.
In another embodiment, the device comprises compressible free-floating structure in the stomach with an attached sleeve which passes through the pylorus and into the duodenum. The device in this embodiment is anchorless and atraumatic, as it is not physically attached to any part of the GI tract and does not damage the GI tissue.
In one embodiment, the device is delivered endoscopically to the stomach via a catheter. The device can be placed through the endoscope, over an endoscope or over a guidewire with endoscopic or fluoroscopic guidance/assistance.
The device has a pre-deployment compressed shape to facilitate insertion and a post-deployment expanded shape that resides in the gastric lumen. Post-deployment volume of the device is significantly larger than pre-deployment volume. In one embodiment, the post-deployment device has a volume of at least 100 ml. The post-deployment device occupies a significant volume in the stomach, thereby reducing available gastric volume available for storage of ingested food. This restricts the amount of food intake, inducing satiety and curbing one's appetite. In one embodiment, the device is also designed to intermittently, with gastric peristalsis, slow or block the passage of the food from the stomach into the small intestine, thereby slowing gastric emptying. In various embodiments, the device also functions to create a biliopancreatic diversion, either by bypassing ingested food past pancreatic secretions or by bypassing pancreatic secretions past ingested food.
In one embodiment, the device comprises a shape memory metal and self-expands once deployed to change from the pre-deployment shape to the post-deployment shape. In another embodiment, the device comprises a temperature sensitive metal that is cooled in its pre-deployment shape and then self-expands when exposed to human body temperature to achieve its post-deployment shape. In another embodiment, an expansion tool is used to apply minimal mechanical force to change the device shape from its pre-deployment shape to its post-deployment shape. In another embodiment, a plastic, polymer, carbon fiber or a bioresorbable material is used to construct the intragastric device.
In one embodiment, the wire structure contains differently weighted material to assist in proper positioning within the stomach. In one embodiment, lighter weighted material is positioned at the top of the wire structure proximate to the top openings and heavier weighted material is positioned at the bottom of the structure, proximate to the bottom openings. This differential weighting insures that the device will be properly situated within the stomach to effectuate the intended effect of slower gastric emptying. In addition, the differential weighting provides for proper gastric positioning without the need of physically anchoring the wire mesh structure to the stomach wall. The differential weight property can also be provided by the ingested food material that enters the device and is selectively accumulated toward the bottom of the device facilitated by the gravitational pull. The differential weight can also be provided by using different amounts of material in the top and bottom halves. The wire mesh structure is free to move about within the stomach while still maintaining its correct top to bottom alignment facilitated by the gravitational pull.
In one embodiment, the device comprises a wire mesh structure which, when in the post-deployment shape, includes mesh openings between the wires of the mesh structure. In one embodiment, the mesh openings are greater than 1 mm in diameter. In one embodiment, the wires of the wire mesh structure are coated with a corrosion-resistant material. The corrosion resistant material prevents exposure and subsequent degradation of the wires of the wire mesh structure from acidic gastric contents once deployed. The corrosion-resistant material completely covers the wires of the wire mesh but does not cover the mesh openings. In one embodiment, the corrosion-resistant material comprises parylene. Parylene is beneficial as a coating in that it is durable, may mitigate nickel ion leaching, and has a lower profile (is thinner once applied). In various embodiments, the corrosion-resistant material comprises silicone, polyester, polyether ether ketone (PEEK), a medical grade epoxy, ceramic, an additional metal, or any other suitable, flexible corrosive resistant material. In one embodiment, the coating metal is tantalum. Tantalum provides corrosive resistance and radiopacity. In one embodiment, wherein the coating is ceramic, the ceramic coating has a thickness of several angstroms. In various embodiments, any one or combination of the above corrosive resistant materials is used to coat the metal of the wire mesh structure.
In one embodiment, the mesh openings are differentially structured to regulate the flow of food in and out of the mesh. In one embodiment, at least one opening on the bottom half of the device is larger than any of the openings on the upper half of the device, allowing food entering the mesh to exit without the need for further reduction in size of food material.
In another embodiment, the intragastric device further includes an anti-migration component, or collar, coupled to a portion of its distal end. The anti-migration component, similar to the wire mesh of the intragastric device, is configurable between a first, compressed configuration for delivery, and a second, expanded configuration once deployed. The anti-migration component functions as a physical stopper preventing passage of the intragastric device through the pylorus. In various embodiments, the anti-migration component has a diameter that is greater than the diameter of a relaxed pylorus. In one embodiment, the anti-migration component comprises an extension of the wire mesh structure of the intragastric device. In another embodiment, the anti-migration component is a separate piece of wire mesh which is attached to a portion of the distal end of the intragastric device. In various embodiments, the anti-migration component has a shape approximating a bumper, half-bumper, disc, saucer, or any other shape which will prevent migration of the device past the pylorus.
In other embodiments, a sleeve can be attached to the intragastric device, where the sleeve extends from the stomach into the duodenum where it empties, or through the duodenum and into the jejunum. In one embodiment, the sleeve functions to transit the sequestered chyme from the wire mesh structure directly to the mid duodenum or mid-jejunum. In another embodiment, the sleeve is coupled to the intragastric device but does not directly receive food from the device. In this embodiment, the proximal end of the sleeve is distal to the device and receives food directly from either the stomach or the duodenum. The food entering the sleeve exits at the distal end, into the duodenum or jejunum, bypassing a portion of the small intestine.
The sleeve therefore acts to bypass portions of the gastrointestinal (GI) tract in order to limit the absorption of specific materials in the intestine. The benefits provided by a sleeve are similar to those provided by Roux-en-Y gastric bypass surgery, namely, weight loss and improvement of type II diabetes.
After implantation, the gastrointestinal device of the present specification, particularly the collar, is in constant physical contact with the patient's anatomy without being actually physically attached to the patient's anatomy. This is accomplished by the sleeve being pulled down by the peristaltic actions of the small intestine. As the sleeve is pulled down, the collar of the wire mesh structure contacts the stomach proximal to the pylorus. The sleeve is constantly in physical contact with the pylorus. However, this constant contact with the pylorus does not block food passage. The openings of the wire mesh structure and the lumen of the sleeve pass food through pylorus without occluding it at any point, allowing the food to pass into the intestines. The intragastric device of the present specification physically engages the gastric emptying region of stomach without fully occluding it any point. The intragastric device of the present specification functions as a variable outlet drain and does not act as a stopper to the passage of food.
The gastrointestinal device of the present specification is designed to maximize the amount of food captured and passed through the sleeve and into the intestines rather than minimizing the amount of food passing into intestines. By being in constant contact with the pylorus and stomach, the device is designed to prevent food from passing around and outside of it. In various embodiments, at least 10% of the food exiting a patient's stomach passes through the device and not around the device. In one embodiment, at least 50% of the food exiting a patient's stomach passes through the device and not around the device. In various embodiments, this food that passes into the device and through the sleeve never comes into contact with the patient's duodenum, thereby allowing the device to function as a true pyloric bypass.
In one embodiment, the device is an inflatable balloon with an attached sleeve, wherein the balloon is not in fluid communication with a lumen of the sleeve and the balloon merely acts to hold the sleeve in position without the need to anchor or fix the sleeve to the gastrointestinal wall. The balloon can be inflated or deflated with fluid and is designed to reside in a person's stomach. The sleeve is flexibly attached to the balloon and has a proximal opening and a distal opening wherein the proximal opening is designed to reside proximal to a patient's ampulla and the distal opening is designed to reside distal to a patient's ampulla. Partially digested food enters the proximal opening and exits the distal opening, bypassing the ampullary region. The sleeve is not anchored or fixed to any portion of the gastrointestinal wall.
Wire Mesh StructureIn various embodiments, the intragastric device comprises a porous three dimensional structure having a pre-deployment shape and a post-deployment shape. In one embodiment, the device, in the post-deployment configuration, comprises a three dimensional wire mesh structure defining an internal volume and having a proximal end and a distal end.
In various embodiments, the wire mesh structure includes free ends or ‘nodes’ comprising bends or curves in the wire of the wire mesh structure wherein these bends or curves are unsupported and not connected to any other portion of the wire mesh. In some embodiments, the wire mesh structure includes two pluralities of nodes. A first plurality is positioned at the proximal end of the structure and a second plurality is positioned at the distal end of the structure. When the wire mesh structure is compressed to its pre-deployment configuration, the first and second plurality of nodes at the proximal and distal ends of the structure respectively, become gathered together or ‘bunched up’. This creates a larger cross-sectional area (or diameter) at the proximal and distal ends of the structure when compared to the cross-sectional area of the compressed structure between said ends. As its cross-sectional area becomes larger, the compressed wire mesh structure becomes increasingly difficult to deploy through a narrow delivery device or catheter. This delivery problem can be addressed in at least two different ways. In various embodiments, the number of nodes in each plurality of nodes is reduced. Reducing the number of nodes in each plurality makes the structure easier to compress and creates a smaller cross-sectional area at the ends of the structure. This reduces the force applied by the compressed structure to the delivery catheter, thereby making it easier to pass the compressed structure through the catheter. In various embodiments, a portion of the nodes from one or both of the first and second plurality of nodes is moved from said ends of the structure and positioned along the body of the structure, creating additional pluralities of nodes. This ‘staggering’ of the nodes reduces the cross-sectional area of the compressed structure at any given point and distributes the force applied by the compressed structure to the delivery catheter, again easing the passage of the delivery structure through the catheter. In various embodiments, the number of nodes in each plurality is reduced and the nodes are staggered in multiple pluralities throughout the structure to reduce and distribute the force applied by the compressed structure to the delivery catheter. Reducing and distributing said force allows for easier delivery and for the use of a delivery catheter having a smaller diameter. Reduced and distributed forces also allow for the creation of larger mesh structures that can be compressed to smaller sizes.
In various embodiments, each plurality of nodes comprises 10 to 100 individual nodes. In one embodiment, each plurality of nodes comprises 44 nodes. In another embodiment, each plurality of nodes comprises 36 nodes. In various embodiments, a wire mesh structure includes 2 to 60 pluralities of nodes distributed latitudinally at different locations along its length. In one embodiment, the nodes are staggered such that at least 10% of the total number of nodes in the structure are positioned at the proximal and distal ends. In various embodiments, no more than 75% of the total number of nodes are positioned in any one plurality of nodes. In various embodiments, the nodes are distributed within at least three different lateral pluralities along the length of the structure.
The compressibility of the wire mesh structure also depends on the flexibility of the mesh. The flexibility, in turn, depends upon, among other variables, the thickness of the wire, the angle of wire intersections, and the number of wires. Regarding the angle of wire intersections, as the wires of the structure are arranged more parallel to one another, the structure becomes more flexible. In various embodiments, the wire mesh structure, in a pre-deployment configuration, has an overall length of 5 to 50 cm and each wire has a thickness in a range of 0.1 to 1 mm. In one embodiment, each wire has a thickness of 0.44 mm. The wires of the wire mesh structure have a bending strain which determines how they behave as the structure is com pressed. In various embodiments, the wires are comprised of a shape memory metal, such as, in one embodiment, Nitinol. The shape memory metal has a certain bending strain percentage beyond which the metal loses its ability to exactly regain its previous shape. The strain percentage (%) can be defined by the following formula:
strain %=2t/R×100
wherein t=thickness of the wire and R=radius of the bend. In one embodiment, once the strain percentage reaches 8%, a permanent change is introduced to the shape memory metal such that it will no longer return fully to its original shape. This factor becomes important as the wire mesh structure is compressed to its pre-deployment shape for delivery. In various embodiments, the wire mesh structure includes a collar or circular extension of the wire mesh at its distal end which functions as an anti-migration component. This collar must me folded out distally during compression such that the compressed structure will fit into the delivery device or catheter. A ‘bump’ in the wire mesh structure is introduced as the collar is folded out during compression. A strain percentage of less than 8% creates a smaller bump in the compressed wire mesh structure, allowing for easier passage of the compressed structure through a delivery catheter. Therefore, in various embodiments, the wire mesh structure is configured having a wire thickness and a bend radius at the collar such that the strain percentage at the collar will be no more than 20%, and preferably less than 8%. In various embodiments, the radius of the collar is less than 10 times the wire thickness. In various embodiments, the strain percentage is in a range of 0.1 to 20% . In various embodiments, the wire of the wire mesh has a thickness of 0.1 to 1.0 mm and the collar has a bend radius of 0.013 to 20 cm. In one embodiment, the wire of the wire mesh has a thickness of 0.4 mm. In various embodiments, the wire thickness and bend radius are configured to satisfy the following statement:
2t<R<2000t
wherein t=thickness of the wire and R=radius of the bend.
In various embodiments, the ends of the wire(s) of the wire mesh structure are terminated in such a way to minimize the possibility of traumatic injury to body tissues during delivery and retrieval and while deployed. In some embodiments, the wire mesh structure comprises a single wire folded into a three dimensional structure. In other embodiments, the wire mesh structure comprises more than one wire joined and folded into a three dimensional structure. In various embodiments, the free ends of the wire or wires are joined by crimping a titanium tube or Nitinol (or other shape memory metal) tube over said free ends. In other embodiments, the free ends of the wire or wires are joined by spot welding said free ends together. In one embodiment, the intersections of the wires are not welded. In another embodiment, the intersections of the wires are welded.
In one embodiment, the wire mesh structure is enveloped in a silicone balloon that compresses to a capsule for delivery. After delivery, the wire mesh structure expands together with the envelope. The balloon envelope slows down the exposure of the wire mesh to acid, which corrodes the Nitinol material of the mesh, thereby prolonging the device life.
SleeveIn various embodiments, the intragastric device of the present specification further comprises a flexible sleeve component coupled to the wire mesh structure. In multiple embodiments, any of the wire mesh structures discussed above is coupled with any of the sleeve components discussed below. The sleeve component comprises an elongate tubular body having a proximal end and a distal end a lumen within.
In one embodiment, the sleeve has a consistent diameter along its entire length. In other embodiments, the sleeve comprises a funnel shape proximate its proximal end wherein the diameter of the sleeve is greatest at the first opening at the proximal end of the sleeve body and then decreases gradually as it extends distally until it reaches a minimum diameter at a position proximal to the midpoint of its length. The diameter then remains constant distally along the remainder of its length.
In various embodiments, wherein the wire mesh structure includes a collar at its distal end, the proximal end of the sleeve is attached to the bottom surface of said collar by one of the means listed above. In various embodiments, when the device is compressed into its pre-deployment configuration, the sleeve body is pulled upon to assist in folding out the collar. If the proximal end of the sleeve is attached to the bottom surface of the collar as described above, the collar is not fully straightened when folded out, resulting in the creation of a large bulge at the collar when the device is in the pre-deployment configuration. The bulge has a large diameter comprising the thickness of the wire mesh structure and double the thickness of the sleeve. Therefore, in preferred embodiments, the proximal end of the sleeve is attached to the free ends, or nodes, of the collar by a plurality of loose sutures. The sleeve is sutured to each node much similar to the way in which the fabric of an umbrella is attached to the end of each spine of the umbrella. When an umbrella is closed, the fabric collapses down to allow for compression. The intragastric device of the present specification functions in a similar manner. In various embodiments, as the wire mesh structure is compressed for loading onto a delivery device, the distal end of the sleeve is pulled upon. The loose sutures attaching the sleeve to the nodes of the wire mesh allow the sleeve to move relative to the wire mesh such that the collar is pulled distally and extended into a more linear shape. Such an attachment avoids the creation of a large bulge at the collar of the pre-deployment configuration. When the sleeve body is pulled upon during compression, the collar is folded out more completely and the resultant bulge has a smaller diameter, comprising only the thickness of the wire mesh structure. In various embodiments, when the intragastric device is in the pre-deployment configuration, there is minimum to zero overlap between the collar and the sleeve. Upon deployment, the shape memory properties of the wire mesh structure cause the collar to pull the sleeve onto itself as it expands, much like an umbrella expanding its fabric as it opens.
In various embodiments, each node at the distal end of the wire mesh structure (or collar) is attached to the proximal end of the sleeve via a suture. This can lead to bulking at the attachment of the wire mesh structure to the sleeve. Therefore, in other embodiments, fewer nodes are sutured to the sleeve. For example, in one embodiment, every other node is sutured to the sleeve to reduce the number of suture knots and decrease bulking. The inclusion of glue and multiple loops in each suture knot can also lead to bulking at the attachment point of the wire mesh structure to the sleeve. As such, in various embodiments, glue is not used and each suture knot is limited to one loop. Suturing of the sleeve to the nodes can lead to sliding of the suture knots along the length of wire comprising the nodes, resulting in unintended movement of the sleeve relative to the wire mesh structure. To prevent sliding, in various embodiments, each suture knot is placed at the first junctions of the wires proximal to each node. In effect, each suture is then placed over two wires and cannot slide along one or the other. To eliminate excessive bulking, in various embodiments, fewer than every first wire junction is sutured to the sleeve. For example, in one embodiment, every other first wire junction is sutured to the sleeve.
In various embodiments, any sharp ends of wires in the wire mesh and/or sleeve are crimped and looped onto themselves or looped outward to act as pulling points for moving the sleeve into the intestines or for connecting the sleeve to the wire mesh structure.
The distal end of the sleeve can be designed to be weighted so that the sleeve remains in an elongated shape extending through a portion of the duodenum. In one embodiment, the sleeve includes a small weight attached to its distal end. In another embodiment, wherein the second opening at the distal end of the sleeve body is positioned along the sleeve body at its distal end, the distal end of the sleeve body further includes a blind pouch. The blind pouch functions to intermittently trap a small portion of food or fluid there within. The trapped food or fluid acts to weigh down the distal end of the sleeve body, thereby keeping the sleeve component elongated. In one embodiment, the distal end of the sleeve is reinforced with at least a second layer to assist in keeping the distal end positioned downward and prevent it from folding up.
In one embodiment, the sleeve comprises a wire mesh configuration having a plurality of nodes, similar to the configuration described above for the wire mesh structure.
In another embodiment, the sleeve component comprises a membrane that is flexible and compressible by the contractions of the small intestine. In one embodiment, the sleeve includes a minimum level of structure which imparts upon the sleeve a minimum amount of structural strength to resist buckling from gastrointestinal forces and remain functional. In one embodiment, the minimum level of structure comprises a single structure extending along at least 10% of a length of the sleeve to provide the sleeve with linear strength. In various embodiments, the single structure is a straight wire, a wire helix, or a wire mesh. In one embodiment, the membranous sleeve component comprises a plurality of horizontal and/or vertical support elements along the length of the sleeve body. In one embodiment, the horizontal elements include wire rings spaced apart along the length of the sleeve body. In various embodiments, the rings are spaced between 2 and 24 inches apart. In one embodiment, the rings are spaced 6 inches apart. In one embodiment, the vertical support elements include elongate metal wires. In various embodiments, the wires are between 2 and 60 inches in length. In one embodiment, the metal wires are 6 inches in length. In another embodiment, the membranous sleeve component comprises a spiral metal wire extending along its length. The spiral metal wire provides support to the sleeve component and maintains its elongated shape. In various embodiments, the spiral metal wire is comprised of a shape memory metal, such as Nitinol. The spiral metal wire must not be too tight such that, once the sleeve in compressed for delivery, it becomes kinked and cannot regain its full shape. In various embodiments, the spiral metal wire of the sleeve has a thickness of 0.1 to 1.0 mm. In one embodiment, the spiral metal wire of the sleeve has a thickness of 0.2 mm. As similarly discussed above with reference to the collar bend radius, the bend radius of the spiral metal wire of the sleeve should be such to create a strain percentage that will be in a range of 0.1 to 20%, and preferably less than 8%. In various embodiments, the strain percentage (%) of the spiral metal wire can be defined by the following formula:
wherein d is the diameter of the wire, Rf is the final bend radius, and Ri is the initial bend radius. Therefore, in various embodiments, the spiral metal wire has a pitch in a range of 5 to 150 mm. In one embodiment, the spiral metal wire has a pitch of 60 mm. In various embodiments, the sleeve includes more than one spiral metal wire to provide greater support while still preventing permanent kinking. In one embodiment, the sleeve includes three spiral metal wires wherein each individual wire has a pitch of 60 mm and the wires are spaced such that the pitch between two separate wires is 20 mm. In another embodiment, the sleeve includes six spiral or helical wires to provide structural support to the sleeve. In various embodiments, the membrane of the sleeve component extends proximally onto the lower portion of the wire mesh structure and covers all or a portion of said lower portion.
The sleeve is flexible and compressible such that during delivery it is restrained in a compressed configuration on the distal end of a delivery device. In one embodiment, the sleeve telescopes into itself to shorten its length and facilitate delivery. In addition, when the device is in the pre-deployment configuration, the sleeve can be folded onto itself to shorten its length and assist with placement in a delivery device or catheter. In various embodiments, the sleeve is folded 2 to 10 times upon itself and then folded or wrapped along a delivery device or catheter for delivery. In one embodiment, the sleeve is fed coaxially over a guidewire, a delivery device or catheter. In another embodiment, the sleeve is folded along the side or around a delivery device or catheter. This helps prevent the sleeve from sticking to the guidewire and/or delivery device/catheter as the guidewire and delivery device/catheter are retracted, which is sometimes encountered when the sleeve has been fed coaxially over the guidewire or delivery device/catheter.
In other embodiments, some intragastric devices of the present embodiment include a sleeve having a shorter length than the lengths described above. In various embodiments, the short sleeve has an overall length of 100-120 mm. In various embodiments, the short sleeve has a funnel shape or cone shape. In some embodiments, the short sleeve comprises a wire formed into a wire mesh structure or braid having a plurality of nodes, similar to the configuration described above for the wire mesh structure. In one embodiment, the braid is created using a single wire. In one embodiment, the wire is composed of a shape memory metal. In one embodiment, the shape memory metal is Nitinol. In other embodiments, the braid is created by machine braiding multiple wires. In some embodiments, the pitch, or distance between nodes, is uniform. In other embodiments, the pitch is variable. The ends of the braid are designed to be atraumatic. In one embodiment, the ends are blunted. In another embodiment, the ends are capped with a soft polymeric tip. In some embodiments, a portion of the short sleeve is coated with a covering. In some embodiments, the covered portion comprises the floating nodes. In one embodiment, the covering is silicone. In various embodiments, the diameter of the proximal end of the sleeve is approximately equal to the outer diameter of an anti-migration collar at the distal end of a wire mesh structure. In such embodiments, the proximal end of the sleeve is fitted over and attaches to the anti-migration collar. In other embodiments, the diameter of the proximal end of the sleeve is smaller than the outer diameter of an anti-migration collar and approximately equal to the diameter of a neck of the collar connecting said collar to said wire mesh structure. In these embodiments, the proximal end of the sleeve is attached to said neck of said collar.
In one embodiment, the number of nodes is uniform across the braid. In one embodiment, the number of nodes is 24. In other embodiments, the number of nodes is variable across the braid. For example, in various embodiments, the short sleeve braid includes 24 nodes at the proximal end and 18 or 12 nodes at the distal end. In these embodiments, the nodes comprising the difference in number of nodes between the two ends (for example, 6 or 12 nodes) are floating nodes and are positioned along the body of the short sleeve.
Once an intragastric device having a short sleeve is deployed, the short sleeve intermittently engages and blocks a patient's pylorus without being anchored to the pylorus. This prevents food from passing through the pylorus and forces the food to pass through the short sleeve from the stomach and into the duodenum, thus regulating gastric outflow. In various embodiments, an opening at the distal end of the short sleeve is 1-30 mm in diameter wherein the size of the diameter determines the rate of gastric outflow. In one embodiment, the opening can be 0 mm when the pylorus is engaged, thereby completely blocking outflow. Therefore, food is allowed to enter the duodenum from the stomach only when the pylorus is not engaged or only partially engaged.
In various embodiments, the sleeve has a high coefficient of friction compared to sleeves of the prior art. In various embodiments, the sleeve has a coefficient of friction ranging from 0.01-0.30. In one embodiment, the sleeve has a coefficient of friction equal to or less than 0.10. It has been encountered with relatively smooth sleeves that, during deployment, the smooth sleeve can become stuck to the inside of a delivery catheter or stuck to itself, resulting in destruction of the sleeve as force is applied to free the sleeve. Therefore, a sleeve with a rougher outer surface can be easier to feed into a delivery device or catheter and then deploy. In various embodiments, the sleeve includes a matte outer surface. In other embodiments, a particulate matter or relatively rough substance, such as corn starch or biocompatible powder, is applied to the outer surface of the sleeve prior to loading the sleeve into a delivery device and deployment.
In various embodiments, the sleeve includes one or more radiopaque markers to ensure proper positioning of the sleeve using radiographic imaging. In various embodiments, the radiopaque markers include a plurality of individual markings along an outer surface of the sleeve body. In other embodiments, the radiopaque marker includes a single line extending along an outer surface of the sleeve body. A spiraled single line can indicate twisting of the sleeve. In still other embodiments, the radiopaque markers include a plurality of individual markings and a single line extending along an outer surface of the sleeve body. In other embodiments, no radiopaque markings are necessary as the wire thickness of the support elements of the sleeve is great enough to allow for radiographic visualization.
In another embodiment, the flexible member or sleeve has a surface optimized for adherence and growth of microorganisms. In one embodiment, the device comprises a rigid member, such as a freely floating mesh structure and a flexible member, such as a freely floating sleeve structure, with surfaces of both the members designed to promote micro-organism adherence and growth. The microorganisms produce a desired therapeutic effect including assistance in weight loss, glycemic control, or treatment of irritable bowel syndrome, clostridium difficile or any other condition responsive to a prebiotic or a probiotic therapy.
Retrieval MechanismIn various embodiments, the wire mesh structure or wire mesh structure with coupled sleeve component includes one or more retrieval mechanisms with at least one retrieval mechanism positioned proximate the at least one opening at the proximal end of the wire mesh structure. In one embodiment, the retrieval mechanism comprises an 80 lb. retrieval suture.
Anti-Migration ComponentIn various embodiments, the wire mesh structure or wire mesh structure with coupled sleeve component includes one or more anti-migration components or collars.
In one embodiment, the anti-migration component is comprised of a metal. In one embodiment, the metal is a shape memory metal, such as Nitinol. The anti-migration component is preferably positioned at the distal end of the wire mesh structure (at the junction of the wire mesh structure with the sleeve component in the embodiment of the device including a sleeve) and, once the device is deployed, comes to rest proximal to the pylorus. The anti-migration component functions to prevent passage of the wire mesh structure or entire device through the pylorus.
In various embodiments, various components of the device, including the wire mesh structure, retrieval mechanism, and/or anti-migration component are coated with a therapeutic drug to enhance functionality of the device.
In various embodiments, the wire mesh structure, hook, and/or anti-migration component include a radiopaque marker for radiographic visualization to facilitate delivery and retrieval. In various embodiments, the wire mesh structure, hook, and/or anti-migration component include an ultrasound marker for ultrasound visualization to facilitate delivery and retrieval.
Delivery DeviceThe present specification also discloses various embodiments of a delivery device used to deploy an intragastric device in the gastrointestinal tract of a patient. An intragastric device is preloaded onto a delivery device which is then used to deliver the wire mesh of the intragastric device into the stomach and the sleeve of the intragastric device into the proximal small intestine.
In one embodiment, a delivery device comprises an elongate tubular body having a coaxial plunger and catheter and a plurality of handles. The handles are manipulated to deploy the sleeve and wire mesh structure of the intragastric device in multiple stages. In one embodiment, the tubular body includes a trigger which controls movement of the various components of the delivery device to effectuate intragastric device deployment.
In various embodiments, the intragastric device can be retrieved using a standard overtube, endoscope, and grasper.
The present invention is directed towards multiple embodiments. The following disclosure is provided in order to enable a person having ordinary skill in the art to practice the invention. Language used in this specification should not be interpreted as a general disavowal of any one specific embodiment or used to limit the claims beyond the meaning of the terms used therein. The general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the invention. Also, the terminology and phraseology used is for the purpose of describing exemplary embodiments and should not be considered limiting. Thus, the present invention is to be accorded the widest scope encompassing numerous alternatives, modifications and equivalents consistent with the principles and features disclosed. For purpose of clarity, details relating to technical material that is known in the technical fields related to the invention have not been described in detail so as not to unnecessarily obscure the present invention.
In some embodiments, a sleeve component is attached to the distal end of the wire mesh structure or the collar of the intragastric device. In various embodiments, the sleeve component of the present specification is made of polytetrafluoroethylene (PTFE) or polyethylene or cast PTFE (e.g., Teflon), PTFE with fluorinated ethylene propylene (FEP) or perfluoroalkoxy (PFA) coating, PFA, extruded FEP and extruded PFA or extruded PTFE or a fluoropolymer or silicone. In one embodiment, a silicone sleeve is manufactured by hand pouring and braiding. In another embodiment, a silicone sleeve is manufactured by machine braiding. In various embodiments, the sleeve component has a length in a range of 6 inches to 6 feet or longer. In one embodiment, the sleeve component has a length of 24 inches. In another embodiment, the sleeve component has a length of 30 inches. In various embodiments, the sleeve component has a diameter in a range of 1 cm to 10 cm. In one embodiment, the sleeve component has a diameter of 3 cm.
In one embodiment, the opening of the funnel shaped sleeve is well suited for attachment to the nodes of the collar positioned at the distal end of the wire mesh structure of some embodiments of the intragastric device.
The wire mesh structure 605 comprises at least one metal wire folded about itself to create a crisscross weave pattern with a plurality of free curved ends, or nodes, along the structure. In its expanded, post-deployment configuration, the wire mesh structure 605 has an oval shape. To facilitate optimal expansion and compression for easier delivery and removal, the wire mesh structure 605 includes a plurality of staggered nodes 606, 607, 608, 609 along its length. A first set of staggered nodes 606 is positioned at the proximal end of the wire mesh structure 605 and circumscribes a first opening 601. In one embodiment, each node in said first set of staggered nodes 606 is bent upwards to extend in a direction opposite from an interior of the wire mesh structure 605. The nodes in said first set of staggered nodes 606 are used as grasping points for a retrieval device during removal of the intragastric device 600. The wire mesh structure 605 includes a second set of staggered nodes 607 distal to said first set 606 and proximal to a midpoint of said wire mesh structure 605. A third set of staggered nodes 608 is positioned distal to said midpoint and proximal to the distal end of the wire mesh structure 605. A fourth set of staggered nodes 609 is positioned at the distal end of the wire mesh structure 605 and comprises the free end of the anti-migration component 620. All of the curves comprising the nodes in each set of staggered nodes 606, 607, 608, 609 are designed to have a bend that is atraumatic to body tissues. The nodes are staggered to prevent bunching of the bending points of the wire and bulking of the wire mesh structure as it is compressed to its pre-deployment configuration. Spreading the nodes along the length of the wire mesh structure allows for an overall smaller diameter of the device once it is compressed.
The sleeve 610 includes a proximal portion 611 and a distal portion 616 which join at a transition point 615 along the sleeve 610 body. Both the proximal portion 611 and the distal portion 616 of the sleeve 610 are funnel shaped, each having a diameter that decreases as the portions 611, 616 extend distally. In one embodiment, the diameter of the proximal portion 611 is substantially the same as the diameter of the anti-migration collar 620 at a proximal end of said proximal portion 611. The diameter of the proximal portion 611 decreases as the proximal portion 611 extends distally until the sleeve 610 transitions into its distal portion 616, at which point the diameters of the proximal portion 611 and the distal portion 616 are equal. The diameter of the distal portion 616 then decreases as said distal portion 616 extends distally. The distal portion 616 of the sleeve 610 ends in a second opening 619 at a distal end of the intragastric device 600. In one embodiment, the proximal portion 611 has a length that is less than a length of the distal portion 616. In various embodiments, the funnel shaped sleeve 610 comprises at least one wire support. In some embodiments, the at least one wire support comprises the same wire(s) in both the proximal portion 611 and distal portion 616. In other embodiments, the proximal portion 611 and distal portion 616 comprise separate wire supports and the wires are joined together at a distal end of the proximal portion 611 and a proximal end of the distal portion 616. In one embodiment, the separate wires are spot welded together. The wire is folded upon itself to create a crisscross weave pattern in the sleeve 610. In both the proximal 611 and distal portions 616, the intersecting sections of the wire come closer to one another as the portions 611, 616 extend distally and the funnel shape narrows, such that the weave pattern becomes tighter at the distal ends of each portion 611, 616. The sleeve 610 includes curves or free ends, similar to the nodes of the wire mesh structure 605, at its proximal end and distal end. The free ends are designed to be atraumatic to body tissues. The free ends at the proximal end of the sleeve 610 are attached to the nodes of the fourth set of staggered nodes 609 of the wire mesh structure 605 via one or more sutures 622. The free ends at the distal end of the sleeve 610 circumscribe the second opening 619. In various embodiments, the sleeve 610 is a short sleeve having a total length in a range of 5 cm-120 cm. In one embodiment, the sleeve 610 is a short sleeve having a total length of 60 cm. In one embodiment, the sleeve 610 includes a soft atraumatic tip 630 at its distal end. The tip 630 contains no wires and is included to prevent injury to the intestinal mucosa from the sleeve tip.
When the sleeve 610 is attached to the wire mesh structure 605, the proximal end of the proximal portion 611 of the sleeve 610 is slid over and covers at least a portion of the anti-migration component 620 such that the proximal portion 611 of the sleeve 610 covers an opening at the distal end of the wire mesh structure. This positioning enables fluid communication between the interior of the wire mesh structure 605 and an interior of the sleeve 610 and establishes a pathway for food from said first opening 601, into said interior of said wire mesh structure 605, through said interior of said sleeve 610, and out of said second opening 619.
The wire mesh structure 705 is similar to the structure 605 discussed with reference to
The sleeve 710 includes a proximal portion 711 and a distal portion 716 which join at a transition point 715 along the sleeve 710 body. The proximal portion 711 of the sleeve 710 is funnel shaped and includes a diameter that decreases as the portion 711 extends distally. In one embodiment, the diameter of the proximal portion 711 is substantially the same as the diameter of the anti-migration collar 720 at a proximal end of said proximal portion 711. The diameter of the proximal portion 711 decreases as the proximal portion 711 extends distally until the sleeve 710 transitions into its distal portion 716, at which point the diameters of the proximal portion 711 and the distal portion 716 are equal. The diameter of the distal portion 716 then continues at the same size as said distal portion 716 extends distally, giving the distal portion 716 a substantially cylindrical shape. The distal portion 716 of the sleeve 710 ends in a second opening 719 at a distal end of the intragastric device 700. In one embodiment, the proximal portion 711 has a length that is less than a length of the distal portion 716.
In various embodiments, the funnel shaped proximal portion 711 of the sleeve 710 comprises at least one wire support. The wire is folded upon itself to create a crisscross weave pattern in the sleeve 710. The intersecting sections of the wire come closer to one another as the portion 711 extends distally and the funnel shape narrows, such that the weave pattern becomes tighter at the distal end of the proximal portion 711. In various embodiments, the distal portion 716 includes at least one helical wire support extending along its cylindrical length. The helical wire support has a consistent pitch such that a resultant helical weave structure has the same pattern along the length of the distal portion 716 of the sleeve 710. In some embodiments, the helical wire support of the distal portion 716 is an extension of the at least one wire support of the proximal portion 711. In other embodiments, the proximal portion 711 and distal portion 716 comprise separate wire supports and the wires are joined together at a distal end of the proximal portion 711 and a proximal end of the distal portion 716. In one embodiment, the separate wires are spot welded together. The sleeve 710 includes curves or free ends, similar to the nodes of the wire mesh structure 705, at its proximal end and distal end. The free ends are designed to be atraumatic to body tissues. The free ends at the proximal end of the sleeve 710 are attached to the nodes of the fourth set of staggered nodes 709 of the wire mesh structure 705 via one or more sutures 722. The free ends at the distal end of the sleeve 710 circumscribe the second opening 719. In various embodiments, the sleeve 710 is a short sleeve having a total length in a range of 5 cm-120 cm. In one embodiment, the sleeve 710 is a short sleeve having a total length of 60 cm. The funnel shaped conical section can vary from being 1% of the total sleeve length to being 100% of the total sleeve length.
When the sleeve 710 is attached to the wire mesh structure 705, the proximal end of the proximal portion 711 of the sleeve 710 is slid over the anti-migration component 720 such that the proximal portion 711 of the sleeve 710 covers an opening at the distal end of the wire mesh structure. This positioning enables fluid communication between the interior of the wire mesh structure 705 and an interior of the sleeve 710 and establishes a pathway for food from said first opening 701, into said interior of said wire mesh structure 705, through said interior of said sleeve 710, and out said second opening 719.
The wire mesh structure 825 is anchorless and occupies a space within the stomach. The wire mesh structure 825 is free to float within the stomach and intermittently exerts gentle, atraumatic stretching forces on a portion of the stomach as it comes into contact with the inner stomach wall. The stretching forces induce the sensation of satiety in the patient. The anti-migration collar 824 is appropriately shaped to receive the attached sleeve 822. Gastric contents enter the wire mesh structure 825 through a first opening 821 at the proximal end of the wire mesh structure 825 or through openings 829 between the wires of the wire mesh structure 825 and are directed into the attached sleeve 822. The gastric contents then pass through the sleeve 822 and empty out a second opening 823 at the distal end of the sleeve 822, either into the duodenum or jejunum, depending on the length of the sleeve 822. The sleeve 822 is pre-attached to the anti-migration collar 824 of the wire mesh structure 825. The Nitinol stent structure embedded in the sleeve 822 provides support to the sleeve 822 and prevents it from torsion or being kinked by actions of the intestinal musculature. Additionally, the Nitinol stent structure provides a gentle, radial stretching force on the small intestinal wall, inducing a sensation of satiety in the patient and preventing the passage of chyme around the sleeve 822.
In some embodiments, wherein the sleeve includes metal wire supports, the ends of the wire or wires are designed to be atraumatic to body tissues. In various embodiments, the wire ends are blunted, folded upon the wire, or welded to other wire ends. In other embodiments, the distal end of the sleeve includes a component designed to make said distal end atraumatic to body tissues.
In one embodiment, the component 910 includes a circular flange 912 which extends outwardly from the outer surface of the component 910 and then in a proximal direction. The flange 912 serves to cover any sharp ends present in the folded distal sleeve end 907 and further protect body tissues from trauma. In various embodiments, the component 910 has a length in a range of 5 mm to 500 mm, an outside diameter in a range of 3 mm to 30 mm, and an inside diameter in a range of 0.5 to 50 mm.
In various embodiments, the delivery device includes atraumatic distal ends.
Referring to
In one embodiment, the wire mesh structure of the intragastric device is covered in an expandable balloon. The balloon forms an enveloping layer on the mesh structure and protects the structure from stomach acids. In one embodiment, the balloon is made up of silicone and can be compressed to the size of a capsule for delivery. As the wire mesh expands after the delivery, if conforms to the shape of the balloon.
In some embodiments, the balloon envelope, and wire mesh, expand to have a volume in a range of 400-450 ml after deployment. In some embodiments, the balloon is inflated with air, saline, water or any other suitable medium to assist with expansion of the balloon and allow for expansion of the wire mesh.
In some embodiments, an intragastric device of the present specification is an anchorless device comprising a compressible free-floating structure instead of the wire mesh structure described in other embodiments. The free-floating structure is attached to a sleeve in a manner similar to the previous embodiments, and the sleeve passes through the pylorus and into the duodenum. In various embodiments, the free-floating component in the stomach keeps the sleeve in place, rendering the sleeve effectively anchorless. That is, the sleeve is not physically attached to any part of the GI tract. In one embodiment, the intragastric device comprising the free-floating component and sleeve is atraumatic and does not damage the GI tissue.
As known in the art, the sleeve is generally anchored or stented below the pylorus. In the present specification, however, a free floating component is attached to the sleeve at its proximal end and designed to keep the sleeve in place by remaining in the area above the pylorus. Therefore, the component stays in the stomach, proximal to the pylorus, and the sleeve extends through the pylorus and into the mid-duodenum. Gastric contents enter the sleeve proximal to the pylorus, travel through the sleeve, and exit the sleeve in the mid-duodenum, bypassing the pylorus, ampulla of Vater, and proximal duodenum. It may be noted that the present embodiment does not use the functionality of the wire mesh structure, which includes food sequestration and delayed gastric emptying.
As described earlier with reference to
Referring to
In one embodiment, the parachute structure is inverted. It may be noted that the normal parachute design might block larger particulate from passing through the pylorus. Inverting the structure allows larger food particles to pass through. In another embodiment, a hole is added at the top of the normal parachute structure to allow larger particles to pass through.
Referring to
In various embodiments, the upper layer 2820 of the free floating structure 2818 is smaller and has a diameter in a range of 3 mm to 30 mm, while the lower layer 2830 is larger. In one embodiment, both the layers are equal in diameter. The free floating structure 2818 is designed to add weight to the proximal end of the sleeve 2815 to keep the sleeve in place after deployment. The device 2800 is anchorless as the sleeve 2815 is not physically attached to any part of the GI tract. Owing to its shape, free floating structure 2818 has no sharp edges and is atraumatic to body tissues. Food enters through the free floating structure 2818 into the sleeve 2815 and exits through the distal end 2835 of the sleeve 2815. In another embodiment, food enters through a hole (not shown) at the proximal end 2834 of the sleeve 2815 and exits through its distal end 2835.
In some embodiments, a stent is inserted at the proximal end of the sleeve to keep the sleeve in place.
Referring to
The orange peel structure 3418 is designed to add weight to the proximal end of the sleeve 3415 to keep the sleeve 3415 in place after deployment. The device 3400 is anchorless as the sleeve 3415 is not physically attached to any part of the GI tract. Owing to its shape, free floating structure 3418 has no sharp edges and is atraumatic to body tissues. Food enters through spaces 3419 in the ribbon of the orange peel shaped structure 3418, through an opening at the proximal end of the sleeve 3415, and exits through the distal end 3435 of the sleeve 3415.
In some embodiments of the present specification, a sleeve of an intragastric device begins just distal to the esophagus, rather than at and proximate the pylorus and extends through the duodenum.
A shown in previous embodiments of
Also, the mesh devices of previous embodiments are used to provide a feeling of fullness. This feature is provided in the present embodiment by applying pressure at the upper end of the stomach, near the esophagus, which would add feeling of fullness. In one embodiment (not shown), an additional free floating structure, such as a parachute, balloon, collar, etc. is added at the proximal end of a similar free floating structure. Thus, there is an upper structure and a lower structure and the two structures are connected to one another. Further, a sleeve is attached to the distal end of the lower structure and the entire device is flexible. In one embodiment, the entire device conforms to shape of stomach. The bottom end applies pressure to the pyloric section to stretch the stomach and the top end applies pressure to the esophageal/cardiac section of stomach to stretch the stomach, both giving a feeling of fullness.
It may be noted that while prior art includes an atraumatic gastrointestinal anchor distal to the pylorus, the embodiments of the present specification differ in that they do not pierce the tissue and keep the anchoring structure above the pylorus. Further, the anchoring structures are free-floating and not attached to any portion of the GI tract, while still keeping the device in place. Hence the present device is essentially anchorless.
In another embodiment, the device comprises a biodegradable atraumatic anchoring component which disintegrates a few months after deployment, leaving the device in place. In some embodiments, the anchoring component degrades after 6 months. In one embodiment, the intragastric device comprises a stent with a sleeve attached to it. The device stays in the GI tract after deployment, and a few months later the sleeve is removed, leaving the stent in place. In one embodiment, a suture connects the stent to the sleeve. For removal, a physician pulls on the suture, allowing the sleeve to detach and be passed. In some embodiments, the sleeve is detached and passed 3 to 6 months following implantation.
In one embodiment, the present specification comprises an anchorless gastrointestinal device having a pre-deployment shape and a post deployment shape and constituting a rigid member and a flexible member wherein the flexible member is longer and thinner than the rigid member in its post-deployment shape and has a surface optimized for adherence and growth of microorganisms. In one embodiment, the rigid member is a freely floating mesh structure and the flexible structure is a freely floating sleeve structure with a surface designed to promote micro-organism adherence and growth. Thus, in one embodiment, gastrointestinal devices of the present specification are used for delivery of prebiotic or probiotic therapy into a patient's small intestine, thereby leading to desired therapeutic effect. In one embodiment, the desired therapeutic effect includes weight loss, glycem is control, or treatment of irritable bowel syndrome, clostridium difficile or any other condition responsive to a prebiotic or a probiotic therapy.
Benefits of probiotics are well known in the art and include the decrease of potentially pathogenic gastro-intestinal microorganisms; the reduction of gastro-intestinal discomfort; the strengthening of the immune system; the improvement of the skin's function; the improvement of bowel regularity; the strengthening of the resistance to cedar pollen allergens; the decrease in body pathogens; the reduction of flatulence and bloating; the protection of DNA; the protection of proteins and lipids from oxidative damage; and the maintaining of individual intestinal microbiota in subjects receiving antibiotic treatment. Probiotics have to be alive when administered. However, most of the probiotics administered orally do not tend to colonize a patient's small bowel and within a few weeks of cessation of probiotic therapy, the therapeutic effect also ceases. Thus, continuous administration of probiotics is required for a sustained therapeutic effect.
Prior art includes instances of probiotics being administered by devices planted endoscopically in a patient's gastrointestinal system. However, administering live bacteria with an anchored device in the gastrointestinal system increases the risk of these bacteria entering the patient's blood stream, leading to serious infections. For example, liver abscesses have been recently reported owing to the use of probiotics administered by an anchored sleeve device. The risk of infection increases multifold in diabetic patients. Therefore, it is not advisable to use probiotics with an anchored sleeve.
The above problems of prior art are overcome and the use of probiotics is leveraged for the benefits of patients in one embodiment of the present specification, by using anchorless devices as described above to deliver probiotics to the patient's gut. In various embodiments, any of the above described anchorless intragastric devices is used, which has a pre-deployment shape and a post deployment shape. The anchorless device comprises a rigid member such as a free floating structure mesh structure, attached to a flexible member, such as a freely floating sleeve structure. In one embodiment, the flexible member has a surface optimized for adherence and growth of microorganisms. In one embodiment, the flexible member comprises a strip, instead of a sleeve, optimized for adherence and growth of microorganisms.
In one embodiment the sleeve structure is impregnated with a probiotic, such as Lactobacillus or Bifidobacterium. In another embodiment, the sleeve structure has a surface area optimized to allow for adherence of microorganisms. In another embodiment, the sleeve structure has a surface optimized to allow for growth of microorganisms. In one embodiment the sleeve structure comprises a corrugated surface. In another embodiment, the sleeve structure has a honey-comb surface. In another embodiment, the sleeve has woven fiber structure.
In another embodiment, the sleeve structure has a surface optimized to allow for formation of a biofilm with a probiotic species, such as Bifidobacterium longum or Lactobacillus reuteri. A biofilm is any group of microorganisms in which cells stick to each other on a surface. These adherent cells are frequently embedded within a self-produced matrix of extracellular polymeric substance (EPS). Biofilm extracellular polymeric substance, which is also referred to as slime, is a polymeric conglomeration generally composed of extracellular DNA, proteins, and polysaccharides. As known in the art, biofilms may form on living or non-living surfaces.
In one embodiment, the sleeve structure has an increased surface area or length to improve biofilm formation.
In one embodiment, the anchorless intragastric devices of the present specification are used to deliver prebiotics to a patient's gut. A prebiotic is a selectively fermented ingredient that allows specific changes, both in the composition and/or activity in the gastrointestinal microflora that confers benefits upon host well-being and health. In diet, prebiotics are typically non-digestible fiber compounds that pass undigested through the upper part of the gastrointestinal tract and stimulate the growth and/or activity of advantageous bacteria that colonize the large bowel by acting as substrate for them. The prebiotic definition does not emphasize a specific bacterial group. Generally, however, it is assumed that a prebiotic should increase the number and/or activity of bifidobacteria and lactic acid bacteria. The importance of the bifidobacteria and the lactic acid bacteria (LABs) is that these groups of bacteria may have several beneficial effects on the host, especially in terms of improving digestion (including enhancing mineral absorption) and the effectiveness and intrinsic strength of the immune system.
Thus, in one embodiment the sleeve component of the anchorless intragastric device is impregnated with a prebiotic. In one embodiment, the sleeve has a microporous structure allowing for certain nutrients (prebiotics) from inside the sleeve to be transferred to the bacteria (probiotics) outside the sleeve.
In another embodiment, the anchorless intragastric devices of the present specification are used to deliver synergistic combinations of probiotics and prebiotics, called synbiotics, to a patient's gut.
In one embodiment, the sleeve structure carrying a prebiotic, probiotic or a combination thereof is used for certain duration to temporarily change the constitution of a patient's microbiome. In another embodiment, the sleeve structure carrying a prebiotic, probiotic or a combination thereof is used for certain duration to permanently change the constitution of a patient's microbiome.
It should be appreciated that the present disclosure is intended to provide a teaching of several exemplary embodiments of the present invention and is should not be limited to the specific structures disclosed herein. Other variations of the disclosed embodiments, which would be understood by those of ordinary skill, are covered by the present application and are within the scope of the invention, as further defined by the claims.
Claims
1.-20. (canceled)
21. An intragastric device comprising:
- a non-porous, compressible anchoring structure having a spiral-shaped configuration with a proximal end, a distal end, and an intermediate portion therebetween that is wider than the proximal and distal ends; and
- an elongate sleeve coupled to said distal end of said anchoring structure and extending distally from said anchoring structure.
22. The intragastric device of claim 21, wherein said anchoring structure is configured to provide positioning support to said sleeve.
23. The intragastric device of claim 21, wherein said anchoring structure comprises a shape memory material.
24. The intragastric device of claim 21, wherein said anchoring structure has a diameter in from 3 mm to 30 mm at its widest part.
25. The intragastric device of claim 21, wherein said sleeve is attached to said anchoring structure by sutures, glue, or a combination thereof.
26. The intragastric device of claim 21, further comprising a second anchoring structure attached to said proximal end of said compressible anchoring structure.
27. The intragastric device of claim 21, wherein the anchoring structure comprises a flat material.
28. The intragastric device of claim 21, wherein the spiral-shaped configuration of the anchoring structure is adapted for food to enter through spaces in the spiral-shaped configuration.
29. The intragastric device of claim 21, wherein said anchoring structure is configurable between a compressed configuration and an expanded configuration.
30. An intragastric device comprising:
- an anchoring structure including a plurality of loops; and
- an elongate sleeve extending distally from said anchoring structure, said sleeve having an upper proximal portion, a middle transitional portion, and a lower distal portion,
- wherein said loops extend radially and outward from the proximal end of said upper proximal portion of said sleeve, and
- wherein said middle transitional portion has a diameter that decreases in size from its proximal end to its distal end and interconnects said upper proximal portion and said lower distal portion.
31. The intragastric device of claim 30, wherein said loops are interconnected around the circumference of said upper proximal portion.
32. The intragastric device of claim 31,
- wherein said upper proximal portion and said lower distal portion each has an approximate consistent diameter along its length,
- wherein said lower distal portion has a length that is greater than a length of said upper proximal portion, and
- wherein a diameter of said upper proximal portion is larger than a diameter of said lower distal portion.
33. The intragastric device of claim 30, wherein said sleeve further comprises a plurality of horizontal support elements along a length of said middle transitional portion and said lower distal portion.
34. The intragastric device of claim 30, wherein said sleeve further comprises a plurality of vertical support elements in the form of elongate metal wires.
35. The intragastric device of claim 30, wherein said anchoring structure comprises a shape memory material.
36. The intragastric device of claim 30, wherein said anchoring structure is configurable between a compressed configuration and an expanded configuration.
37. The intragastric device of claim 30, wherein said sleeve comprises a membrane.
Type: Application
Filed: Aug 27, 2020
Publication Date: Jan 21, 2021
Inventors: Virender K. Sharma (Paradise Valley, AZ), Raghuveer Basude (Freemont, CA)
Application Number: 17/004,795
