Patent Description:
The present disclosure relates generally to the field of medical devices and establishing fluid communication between body lumens. In particular, the present disclosure relates to devices and methods for establishing a permanent open flow or access passage between body lumens.

The desire to establish access to body lumens to create fluid communication from one to the other is present under various circumstances and conditions. A variety of medical devices (e.g., drainage stents, etc.) are able to establish open flow or access passages between body lumens. These medical devices are generally not indicated for long-term use, and are often removed from the patient within weeks or months after placement. Once the medical device has been removed, the rapidly replenishing cells of the mucosal layer of each body lumen may inherently close or seal the opening (e.g., fistula, anastomosis, etc.). While this self-sealing ability may be advantageous in certain circumstances, various medical conditions require a long term or permanent opening to be maintained between the body lumens after the anastomotic device has been removed from the patient.

For example, blockage of bile flow from the gallbladder to the common bile duct (CBD) causes accumulation of bile within the gallbladder, leading to jaundice in the short term and potentially life-threatening consequences in the long term. Commercially available drainage devices (e.g., Axios™ Stent, Boston Scientific Corporation) may be placed to provide relief from acute cholecystitis by draining bile and/or gallstones from the gallbladder to the duodenum. Since these drainage devices are not indicated for permanent implantation, the standard of care for treating chronic cholecystitis is gallbladder removal. Approximately <NUM>,<NUM> gallbladder removal procedures are performed each year in the U.

A variety of advantageous medical outcomes may be realized by the devices and/or methods of the present disclosure, for example, placing the tissue walls of first and second body lumens in direct contact such that the apposed muscularis layers fuse together to form a long term or permanent open flow or access passage that prevents or significantly inhibits closure or sealing. <CIT> relates to a tissue lumen stent with a body having an elongated tubular configuration and a foreshortened configuration. In the foreshortened configuration, a downstream end and an upstream end of the body expand radially into a downstream flange and a flared upstream portion, leaving a generally cylindrical saddle region therebetween. <CIT> relates to a stent graft system for intraluminal deployment in an aorta and a branch vessel. The system includes an aorta stent graft for deployment within an aorta and defining a lumen for the passage of blood therethrough, and having a fenestration aligned so as to allow blood to flow to a contiguous branch vessel. A branch vessel prosthesis has a flaring portion, a tubular portion and an anchoring device. Upon deployment, the tubular portion passes through the fenestration and into the branch vessel, and the anchoring device affixes the position of the tubular portion within the branch vessel. The flaring portion is retained within the lumen of the aorta stent graft and is maintained against an inside wall of the aorta stent graft to thereby bias the aorta stent graft toward the branch vessel. <CIT> relates to a vascular device for reducing blood flow in a first vessel or a first graft to enable increased blood flow in a second vessel or second graft. The vascular device includes a support structure having a proximal portion, a distal portion and an intermediate portion, the support structure movable from a reduced profile insertion position to an expanded placement position. A covering material is supported by the structure, the intermediate portion in the expanded position having a transverse dimension less than a transverse dimension of the proximal and distal portions to restrict blood flow through the device and thereby increase blood flow to the second vessel or second graft.

In one aspect, the present disclosure relates to a medical device comprising an elongate body forming a lumen and including a proximal portion, a distal portion, a length and a diameter. The elongate body may include an elongate tubular configuration, and a foreshortened configuration where the proximal portion may expand into a proximal retention member and the distal portion may expand into a distal retention member leaving a cylindrical saddle region therebetween. A plurality of proximal tissue-engaging elements may be disposed along an outer surface of the cylindrical saddle region distal to the proximal retention member, and a plurality of distal tissue-engaging elements may be disposed along an outer surface of the cylindrical saddle region proximal to the distal retention member. A first end of each proximal tissue-engaging element may be attached to the outer surface of the cylindrical saddle region, and a second end of each proximal tissue-engaging element may be unattached and extend toward the distal retention member. A first end of each distal tissue-engaging element may be attached to the outer surface of the cylindrical saddle region, and a second end of each distal tissue-engaging element may be unattached and extend toward the proximal retention member. The unattached second end of each proximal tissue-engaging element may be elevated about the outer surface of the cylindrical saddle region. The unattached second end of each distal tissue-engaging element may be elevated about the outer surface of the cylindrical saddle region. The unattached second end of each proximal tissue-engaging element may be configured to penetrate a tissue wall of a first body lumen. The unattached second end of each distal tissue-engaging element may be configured to penetrate a tissue wall of a second body lumen. The plurality of proximal and/or distal tissue-engaging elements may lay flat against the outer surface of the elongate body when in the elongate tubular configuration. A surface of the proximal retention member may be configured to contact an inner surface of a tissue wall of a first body lumen, and a surface of the distal retention member may be configured to contact an inner surface of a tissue wall of a second body lumen. The tissue walls of the first and second body lumens may be apposed between the proximal and distal retention members along the cylindrical saddle region. A portion of the tissue wall of the first body lumen engaged by the plurality of proximal tissue-engaging elements may deflect along the cylindrical saddle region toward the distal retention member, and a portion of the tissue wall of the second body lumen engaged by the plurality of distal tissue-engaging elements may deflect along the cylindrical saddle region toward the proximal retention member, thereby placing a tissue layer (e.g., muscularis layer) of the tissue wall of the first body lumen in contact with a tissue layer (e.g., muscularis layer) of the tissue wall of the second body lumen.

In another aspect, the present disclosure relates to a medical device comprising an elongate body forming a lumen and comprising a proximal portion, a distal portion, a length and a diameter. The elongate body may include an elongate tubular configuration, and a foreshortened configuration where the proximal portion may expand into a proximal retention member and the distal portion may expand into a distal retention member leaving a cylindrical saddle region therebetween. A first magnet may be disposed within proximal retention member, and a second magnet may be disposed within the distal retention member. An attractive force between the first and second magnets may urge the proximal and distal retention members toward each other. A surface of the proximal retention member may be configured to contact an inner surface of a tissue wall of a first body lumen, and a surface of the distal retention member may be configured to contact an inner surface of a tissue wall of a second body lumen. The tissue walls of the first and second body lumens may be apposed between the proximal and distal retention members along the cylindrical saddle region. The surface of the proximal retention member may cause necrosis within the tissue wall of the first body lumen, and the surface of the distal retention member may cause necrosis within the tissue wall of the second body lumen. The necrosis within the tissue walls of the first and second body lumens may expose and place a healthy tissue layer (e.g., muscularis layer) of the first and second body lumens in contact with each other.

In another aspect, the present disclosure relates to a medical device comprising an elongate body forming a lumen and comprising a proximal portion, a distal portion, a length and a diameter. The elongate body may include an elongate tubular configuration, and a foreshortened configuration where the proximal portion may expand into a proximal retention member and the distal portion may expand into a distal retention member leaving a cylindrical saddle region therebetween. A filament may be threaded through a portion of the elongate body to effectuate compression of the proximal and distal ends toward each other. For example, a first end of the filament may be attached to a proximal end of the medical device at a first location, a second end of the filament may be unattached and extend from the proximal end of the medical device at a second location, and a portion of the filament between the first and second ends may form a loop extending along the cylindrical saddle region between the proximal and distal retention members. Proximally retracting the second end of the filament may urge the proximal and distal retention members toward each other. The medical device may further include a locking member attached to the elongate body adjacent to the second location. The locking member may be configured to secure a portion of the filament. A surface of the proximal retention member may be configured to contact an inner surface of a tissue wall of a first body lumen, and a surface of the distal retention member may be configured to contact an inner surface of a tissue wall of a second body lumen. The tissue walls of the first and second body lumens may be apposed between the proximal and distal retention members along the cylindrical saddle region. The surface of the proximal retention member may cause necrosis within the tissue wall of the first body lumen, and the surface of the distal retention member may cause necrosis within the tissue wall of the second body lumen. The necrosis within the tissue walls of the first and second body lumens may expose and place a healthy tissue layer (e.g., muscularis layer) of the first and second body lumens in contact with each other.

In another aspect, the present disclosure relates to a medical device comprising an elongate body forming a lumen and comprising a proximal portion, a distal portion, a length and a diameter. The elongate body may include an elongate tubular configuration, and a foreshortened configuration where the proximal portion may expand into a proximal retention member and the distal portion may expand into a distal retention member leaving a cylindrical saddle region therebetween. The medical device may become heated in the presence of energy, including MRI energy, and cause necrosis within the tissue walls of the first and second body lumens. The necrosis within the tissue walls of the first and second body lumens may expose and place a healthy tissue layer (e.g., muscularis layer) of the first and second body lumens in contact with each other.

In another aspect, the present disclosure relates to a medical device comprising a first flexible member which includes an inner surface, an outer surface and a first opening extending therebetween, and second flexible member comprising an inner surface, an outer surface and a second opening therebetween. A plurality of tabs may extend from the inner surface of the second flexible member, and a plurality of recesses may be formed within the inner surface of the first flexible member. Each recess of the first flexible member may be configured to receive a corresponding tab of the second flexible member such that the first and second openings may align to form a combined opening. The inner surface of the first flexible member and the inner surface of the second flexible member may be separated by a distance when the plurality of tabs may be received within the plurality of recesses. The plurality of tabs may be configured to penetrate the tissue walls of a first and second body lumen. The plurality of tabs may be configured to extend through an opening between the tissue walls a first and second body lumen.

The present disclosure is not limited to the particular embodiments described. The terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting beyond the scope of the appended claims. Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the disclosure belongs.

Although embodiments of the present disclosure are described with specific reference to medical devices (e.g., stents, etc.) and systems for drainage of the gallbladder, it should be appreciated that such medical devices may be used in a variety of medical procedures (e.g., external biliary drain conversion, enteroenterostomy, gastrojejumostomy, gastroduodenostomy and gastroileostomy, etc.) to establish and/or maintain a temporary or permanent open flow or drainage passage from or between a variety of body organs, lumens, ducts, vessels, fistulas, cysts and spaces (e.g., the dermis, stomach, duodenum, jejunum, small intestine, gallbladder, kidneys, pancreas, biliary / pancreatic trees, bladder, ureter, abscesses, walled-off pancreatic necrosis (WOPN), bile ducts, etc.). The devices can be inserted via different access points and approaches, e.g., percutaneously, endoscopically, laparoscopically or some combination thereof. The medical devices disclosed herein are self-expanding, but in other embodiments the medical device may be expandable by other means, including, e.g., a balloon catheter. Moreover, such medical devices are not limited to drainage, but may facilitate access to organs, vessels or body lumens for other purposes, such as creating a path to divert or bypass fluids or solids from one location to another, removing obstructions and/or delivering therapy, including non-invasive or minimally invasive manipulation of the tissue within the organ and/or the introduction of pharmacological agents via the open flow passage.

It will be further understood that the terms "comprises" and/or "comprising," or "includes" and/or "including" when used herein, specify the presence of stated features, regions, steps, elements and/or components, but do not preclude the presence or addition of one or more other features, regions, integers, steps, operations, elements, components and/or groups thereof.

As used herein, the term "distal" refers to the end farthest away from the medical professional when introducing a device into a patient, while the term "proximal" refers to the end closest to the medical professional when introducing a device into a patient.

In one embodiment, the present disclosure relates to a medical device (e.g., self-expanding drainage stent, etc.) configured to extend between first and second body lumens and align the respective muscularis layers of each body lumen to establish a long term or permanent open flow or access passage therebetween. Referring to <FIG>, in one embodiment, a medical device <NUM> of the present disclosure may include an elongate body <NUM> forming a lumen and comprising a proximal portion, a distal portion, a length and a diameter. The elongate body <NUM> may include an elongate tubular configuration (e.g., constrained, unexpanded or delivery configuration; not shown), and a foreshortened configuration (e.g., unconstrained, expanded or deployed configuration) where the proximal portion <NUM> radially expands into a proximal retention member <NUM>, and the distal portion <NUM> radially expands into a distal retention member <NUM>, leaving a cylindrical saddle region <NUM> extending therebetween. A diameter of the cylindrical saddle region <NUM> may be greater than a diameter of the elongate body <NUM> in the elongate tubular configuration. The proximal and distal retention members <NUM>, <NUM> may extend perpendicular to a circumference of the elongate body <NUM> to define respective planar surfaces 114a, 124a. In various embodiments, the angle of the retention members relative to the circumference of the elongate body may assume other degrees or may change degrees along the retention members creating inflection points in the retention members. A plurality of proximal tissue-engaging elements <NUM> may be disposed along an outer surface of the cylindrical saddle region <NUM> at a location distal to the proximal retention member <NUM>, and a plurality of distal tissue-engaging elements <NUM> may be disposed along an outer surface of the cylindrical saddle region <NUM> at a location proximal to the distal retention member <NUM>. A first end <NUM> of each of the proximal tissue-engaging elements <NUM> may be attached to the outer surface of the cylindrical saddle region <NUM>, and a second end <NUM> of each of the proximal tissue-engaging elements <NUM> may be unattached (e.g., free) and extend towards the distal retention member <NUM>. A first end <NUM> of each of the distal tissue-engaging elements <NUM> may be attached to the outer surface of the cylindrical saddle region <NUM>, and a second end <NUM> of each of the distal tissue-engaging elements <NUM> may be unattached (e.g., free) and extend towards the proximal retention member <NUM>. In the elongate tubular configuration, the proximal and distal tissue-engaging elements <NUM>, <NUM> may be disposed along (e.g., lay flat against) an outer surface of the elongate body. As the elongate body moves to the foreshortened configuration, the proximal and distal tissue-engaging elements <NUM>, <NUM> may deflect outward to extend along and above the outer surface of the cylindrical saddle region <NUM> (e.g., substantially parallel to, or at an acute angle, relative to a longitudinal axis of the cylindrical saddle region).

In various embodiments, the first end <NUM>, <NUM> of any or all of the first and second tissue-engaging elements <NUM>, <NUM> may be affixed to the outer surface of the cylindrical saddle region <NUM> using a suitable glue, adhesive, resin or other bonding techniques, as are commonly known in the art. In addition, or alternatively, the proximal and/or distal tissue-engaging elements <NUM>, <NUM> may be formed as extensions or projections of the woven, knitted or braided filament comprising the elongate body <NUM>. Any of second ends <NUM>, <NUM> of the proximal and distal tissue-engaging elements <NUM>, <NUM> may be sharpened, pointed or otherwise configured to penetrate the tissue wall of a respective first or second body lumen, as discussed below. In addition, any of the proximal and distal tissue-engaging elements <NUM>, <NUM> may further include one or more barbs, hooks, fingers and/or teeth, etc. configured to secure the tissue-engaging element(s) within the tissue wall of the respective first or second body lumen.

Although the proximal and distal tissue-engaging elements <NUM>, <NUM> of <FIG> are depicted as evenly spaced about an outer circumference of the cylindrical saddle region <NUM> and immediately adjacent to the respective proximal and distal retention members <NUM>, <NUM>, in various embodiments, the proximal and/or distal tissue-engaging elements <NUM>, <NUM> may include a variety of shapes, sizes, numbers, orientations, patterns and/or spacing along the cylindrical saddle region. In addition, or alternatively, in various embodiments the tissue-engaging elements are not limited to the cylindrical saddle region, but may be positioned on or along the proximal and/or distal retention members, including the planar tissue-facing surfaces.

In one embodiment, a medical device <NUM> of the present disclosure may be positioned within a patient such that the proximal and distal tissue-engaging elements <NUM>, <NUM> reorient a portion of the respective first and second body lumens as the medical device moves from the elongate tubular to foreshortened configuration to place the muscularis layers of the first and second body lumens in contact along an outer surface of the cylindrical saddle region <NUM>. Referring to <FIG>, in use and by way of example, a medical device <NUM> of the present disclosure may be disposed in the elongate tubular configuration within the lumen of a tissue-penetrating element <NUM>. A sharpened distal end <NUM> of the tissue-penetrating element <NUM> may be advanced through the tissue wall <NUM> of a first body lumen <NUM> (e.g., the stomach or duodenum) and through the tissue wall <NUM> of a second body lumen <NUM> (e.g., the gallbladder).

In various embodiments, the tissue penetrating element <NUM> may be advanced over a guidewire <NUM> previously advanced through the first and second body lumens such that a distal end of the guidewire is disposed within the second body lumen. Alternatively, in the method above, a separate instrument with a sharpened distal tip may be advanced along the path above and into the second body lumen to create a path. A guidewire is put in place, or left in place if used to guide the separate instrument, and the separate instrument is withdrawn over the guidewire. A medical device, according to the various embodiments described above, loaded on a delivery catheter, may be inserted over the guidewire, and the medical device then deployed according to the steps outlined above.

Referring to <FIG>, a distal portion <NUM> of the medical device <NUM> may then be advanced distally beyond the lumen of the tissue-penetrating element <NUM> such that the distal tissue-engaging elements <NUM> are deployed, e.g., removed from constraint within the lumen of the tissue penetrating element <NUM>. Referring to <FIG>, the tissue-penetrating element <NUM> may then be proximally retracted such that at least some of the distal tissue-engaging elements <NUM> engage (e.g., pierce or penetrate) a portion of the tissue wall <NUM> of the second body lumen <NUM> adjacent to the opening formed by the sharpened distal end <NUM>. As the tissue-penetrating element <NUM> is further proximally retracted, a portion of the tissue wall <NUM> of the second body lumen <NUM> may be reoriented, e.g., deflected or turned toward the tissue wall <NUM> of the first body lumen <NUM>.

Referring to <FIG>, the distal portion <NUM> of the medical device <NUM> may then be further advanced distally beyond the lumen of the tissue-penetrating element <NUM> such that the distal retention member <NUM> is fully deployed within the second body lumen <NUM> and the planar surface 124a is placed in contact with the inner surface of the tissue wall <NUM>. Still referring to <FIG>, as the distal retention member <NUM> and a portion of the cylindrical saddle region <NUM> are deployed from within the tissue-penetrating element <NUM>, the portion of the tissue wall <NUM> of the second body lumen <NUM> engaged by the distal tissue-engaging elements <NUM> may be further reoriented to face the tissue wall <NUM> of the first body lumen <NUM>. Referring to <FIG> and <FIG>, the tissue-penetrating element <NUM> may then be further proximally retracted into the first body lumen <NUM>, and a proximal portion <NUM> of the medical device <NUM> advanced distally beyond the lumen of the tissue-penetrating element <NUM> such that the proximal tissue-engaging elements <NUM> are deployed, e.g., removed from constraint within the lumen of the tissue penetrating element <NUM>, and placed in contact with a portion of the tissue wall <NUM> of the first body lumen <NUM> adjacent to the opening formed by the sharpened distal end <NUM>. Referring to <FIG>, the proximal portion <NUM> of the medical device <NUM> may then be further advanced distally beyond the lumen of the tissue-penetrating element <NUM> such that the proximal retention member <NUM> is fully deployed within the first body lumen <NUM> and the planar surface 114a is placed in contact with the inner surface of the tissue wall <NUM>. In one embodiment, as the proximal retention member <NUM> and remaining portion of the cylindrical saddle region <NUM> are deployed from within the tissue-penetrating element <NUM>, the portion of the tissue wall <NUM> of the first body lumen <NUM> engaged by one or more of the proximal tissue-engaging elements <NUM> may be reoriented to face the previously reoriented tissue wall <NUM> of the second body lumen <NUM>, thereby placing the respective muscularis layers <NUM>, <NUM> of the first and second body lumens <NUM>, <NUM> in contact along the cylindrical saddle region <NUM>.

In various embodiments, the proximal and distal tissue-engaging elements <NUM>, <NUM> may be sufficiently flexible or deformable to allow the medical device <NUM> to be removed from the patient without causing substantial trauma to the respective tissue layers. In addition, or alternatively, any or all of the proximal and distal tissue-engaging elements may be formed from a biodegradable or bioerodible material configured to dissolve after the muscularis layers <NUM>, <NUM> have fused, thereby allowing the medical device to be more easily removed from the patient.

In one embodiment, a medical device <NUM> of the present disclosure may be positioned within a patient such that the proximal and distal retention members cause selective and localized tissue necrosis of the first and second body lumens to expose adjacent portions of the muscularis layer of each body lumen along an outer surface of the cylindrical saddle. Referring to <FIG>, in one embodiment, a medical device <NUM> of the present disclosure may include an elongate body <NUM> forming a lumen and comprising a proximal portion <NUM>, a distal portion <NUM>, a length and a diameter. The elongate body <NUM> may include an elongate tubular configuration (e.g., constrained, unexpanded or delivery configuration; not shown), and a foreshortened configuration (e.g., unconstrained, expanded or deployed configuration) where the proximal portion <NUM> radially expands into a proximal retention member <NUM>, and the distal portion <NUM> radially expands into a distal retention member <NUM>, leaving a cylindrical saddle region <NUM> extending therebetween. A diameter of the cylindrical saddle region <NUM> may be greater than a diameter of the elongate body <NUM> in the elongate tubular configuration. The proximal and distal retention members <NUM>, <NUM> may extend perpendicular to a circumference of the elongate body <NUM> to define respective planar surfaces 214a, 224a. A first magnet <NUM> may be disposed within the proximal retention member <NUM>, and a second magnet <NUM> may be disposed within the distal retention member <NUM>. The first and second magnets <NUM>, <NUM> may be disposed within the respective first and second retention members <NUM>, <NUM> such that the polarities of each magnet provide an attractive force therebetween about a full circumference (e.g., <NUM> degrees) of the cylindrical saddle region <NUM>. As discussed in greater detail below, the medical device <NUM> may be disposed between first and second body lumens <NUM>, <NUM> such that the planar surface 214a of the proximal retention member <NUM> contacts and presses against the tissue wall <NUM> of the first body lumen <NUM>, and the planar surface 224a of the distal retention member <NUM> contacts and presses against the tissue wall <NUM> of the second body lumen <NUM> to place the body lumens in contact along the cylindrical saddle region <NUM> (<FIG>). In one embodiment, the attractive force between the first and second magnets <NUM>, <NUM> may urge the proximal and distal retention members <NUM>, <NUM> toward each other, thereby shortening the cylindrical saddle region <NUM> and providing constant and consistent pressure between the planar surfaces 214a, 224a and the respective inner surfaces of each tissue wall <NUM>, <NUM>. In addition, the outer surfaces of each tissue wall may also be compressed against each other between the proximal and distal retention members <NUM>, <NUM>. The constant and consistent pressure exerted on the inner and outer surfaces of each tissue wall <NUM>, <NUM> may cause selective and localized necrosis at a specific depth of each tissue layer. For example, the depth of necrosis of the first and second tissue walls <NUM>, <NUM> may be limited to the mucosal layers <NUM>, <NUM> to selectively expose and place in contact free ends of the muscularis layers <NUM>, <NUM> along the cylindrical saddle region <NUM>.

In one embodiment, the medical device <NUM> may be positioned between the first and second body lumens by following the exemplary steps outlined in <FIG>, as discussed above, with the exception that the tissue walls <NUM>, <NUM> of the first and second body lumens <NUM>, <NUM> are placed in contact along the cylindrical saddle region <NUM>, e.g., the respective tissue walls are not reoriented by proximal and distal tissue-engaging elements. Referring to <FIG>, in one embodiment, each of the first and second magnets <NUM>, <NUM> may include a series of magnet fragments 150a-f, 152a-f loaded onto a delivery wire <NUM>. With the medical device <NUM> properly positioned between the first and second body lumens <NUM>, <NUM>, a delivery device <NUM> (e.g., endoscope, etc.) may be advanced into the second body lumen <NUM> through the lumen of the medical device <NUM>. The delivery wire <NUM>, loaded with a series of magnet fragments 152a-f, may be advanced through the delivery device <NUM> into the second body lumen <NUM>. The delivery device <NUM> may then be proximally retracted (<FIG>) into the medical device <NUM>, and a proximal and distal end of the delivery wire <NUM> proximally retracted such that the exposed magnetic fragments 152a-f, e.g., disposed outside the delivery device <NUM>, sequentially snap or fall into place within the open inner circumference of the distal retention member <NUM> (<FIG>. With the magnetic fragments 152a-f disposed within the distal retention member <NUM>, one end of the delivery wire <NUM> may be released while the other end is proximally retracted to remove the delivery wire <NUM> from the medical device <NUM>. This process may be repeated to place magnetic fragments 150a-f within the proximal retention member <NUM> (<FIG>). With the magnetic fragments 150a-f, 152a-f fully deployed within the proximal and distal retention members <NUM>, <NUM>, selective tissue necrosis of the mucosal layers <NUM>, <NUM>, and fusion of the muscularis layers <NUM>, <NUM> may proceed as discussed above. Referring to <FIG>, in one embodiment, each of the first and second magnets <NUM>, <NUM> may include a flexible magnet configured to move between a restrained (e.g., linear) configuration and an unconstrained (e.g., non-linear or circular) configuration. With the medical device <NUM> properly positioned between the first and second body lumens <NUM>, <NUM>, a delivery device <NUM> (e.g., endoscope) may be advanced into the second body lumen <NUM> through the lumen of the medical device <NUM> (<FIG>). The flexible magnet <NUM> may be advanced through the delivery device <NUM> into the second body lumen, such that the magnet <NUM> moves to the non-constrained configuration (<FIG>). A medical tool <NUM> (e.g., grasper, etc.) may be passed through the endoscope to grasp and pull the flexible magnet <NUM> into the medical device. The flexible magnet <NUM> may deform as it enters the lumen of the medical device and expand (e.g., snap) into the distal retention member <NUM> as the medical tool is proximally retracted (<FIG>). This process may be repeated to place the flexible magnet <NUM> within the proximal retention member <NUM> (<FIG>). With the flexible magnets <NUM>, <NUM> fully deployed within the proximal and distal retention members <NUM>, <NUM>, selective tissue necrosis of the mucosal layers <NUM>, <NUM>, and fusion of the muscularis layers <NUM>, <NUM> may proceed as discussed above.

In various embodiments, one or more magnets may be positioned on or adjacent to (e.g., alongside) the proximal and/or distal retention members to promote selective tissue necrosis of the mucosal layers, and fusion of the muscularis layers. In other embodiments, magnets may be used in retention members of these devices and other devices to help maintain adjacent tissue layers in apposition for drainage, without the magnets necessarily causing necrosis and fusion.

Referring to <FIG>, in one embodiment, a medical device <NUM> of the present disclosure may include an elongate body forming a lumen and comprising a proximal portion, a distal portion, a length and a diameter. The elongate body <NUM> may include an elongate tubular configuration (e.g., constrained, unexpanded or delivery configuration; not shown), and a foreshortened configuration (e.g., unconstrained, expanded or deployed configuration) where the proximal portion <NUM> radially expands into a proximal retention member <NUM>, and the distal portion <NUM> radially expands into a distal retention member <NUM>, leaving a cylindrical saddle region <NUM> extending therebetween. A diameter of the cylindrical saddle region <NUM> may be greater than a diameter of the elongate body <NUM> in the elongate tubular configuration. The proximal and distal retention members <NUM>, <NUM> may extend perpendicular to a circumference of the elongate body <NUM> to define respective planar surfaces 314a, 324a. A filament <NUM> (e.g., suture, thread, nitinol wire, medical grade nylon, etc.) may be threaded through a portion of the elongate body (e.g., through the woven, knitted or braided filament forming the elongate body) such that a first end <NUM> of the filament <NUM> is attached to a proximal end of the medical device <NUM> at a first location (e.g., proximal to the proximal retention member <NUM>), and a second end <NUM> of the filament <NUM> is unattached and extends proximally beyond the proximal end of the medical device <NUM> at a second location different than the first location. For example, the first and second locations may be on substantially opposite sides of the medical device (e.g., separated by <NUM> degrees). A portion of the filament <NUM> between the first and second ends <NUM>, <NUM> may form a loop extending along the cylindrical saddle region <NUM> between the proximal and distal retention members <NUM>, <NUM>. In various embodiments, the first end <NUM> of the filament <NUM> may be affixed to the proximal end of the medical device using a suitable knot, glue, adhesive, resin or other bonding techniques, as are commonly known in the art. In various embodiments, the filament <NUM> may be configured to slide through the woven, knitted or braided filament which forms the elongate body such that proximally retracting the second end <NUM> of the filament <NUM>, while the medical device is immobilized (e.g., disposed between first and second body lumens) in the foreshortened configuration, may urge the proximal and distal retention members <NUM>, <NUM> toward each other, thereby shortening the cylindrical saddle region <NUM>. A locking member <NUM> (e.g., cleat, tie-off, etc.) may be attached to the medical device adjacent to the second location. In addition, or alternatively, the locking member may be integrally formed from a portion of the filament which forms the elongate body <NUM>. The locking member <NUM> may be configured to securingly receive/engage a portion of the filament <NUM> (e.g., loops, windings, etc.) after the second end <NUM> of the filament <NUM> has been proximally retracted, thereby maintaining the proximal and distal retention members <NUM>, <NUM> in the compressed (e.g., further foreshortened) configuration.

In various embodiments, the filament <NUM> may be proximally retracted and "tied-off" to the locking member <NUM> to establish the desired amount of pressure to the tissue walls <NUM>, <NUM> of the first and second body lumens <NUM>, <NUM>, as discussed below. A distance between the proximal and distal retention members <NUM>, <NUM> (and pressure applied to the respective tissue walls) may be adjusted as necessary by securing different portions of the filament <NUM> to the locking member <NUM>. For example, additional force may be applied between the respective tissue walls by releasing (e.g., untying) the filament <NUM> from the locking member <NUM>, further proximally retracting the second end <NUM> and re-securing the filament <NUM> to the locking member <NUM>. Similarly, the force applied between the respective tissue walls may be decreased by releasing the filament <NUM> from the locking member <NUM>, allowing the second end <NUM> to slide distally and re-securing the filament <NUM> to the locking member <NUM>. Alternatively, the filament <NUM> may be released from the locking member <NUM> and the free end <NUM> allowed to slide distally without being re-secured to the locking member <NUM> as a first step in removing the medical device <NUM> from the patient.

In one embodiment, the medical device <NUM> may be positioned between the first and second body lumens by following the exemplary steps outlined in <FIG>, as discussed above, with the exception that the tissue walls <NUM>, <NUM> of the first and second body lumens <NUM>, <NUM> are placed in contact along the cylindrical saddle region <NUM>, e.g., the respective tissue walls are not reoriented by proximal and distal tissue-engaging elements. With the medical device properly positioned between the first and second body lumens <NUM>, <NUM>, the planar surface 314a of the proximal retention member <NUM> may contact and press against the tissue wall <NUM> of the first body lumen <NUM>, and the planar surface 324a of the distal retention member <NUM> may contact and press against the tissue wall <NUM> of the second body lumen <NUM> to place the body lumens in contact along the cylindrical saddle region <NUM> (<FIG>). The second end <NUM> of the filament <NUM> may then be proximally retracted (e.g., using a suitable grasping member, etc.) to urge the proximal and distal retention members <NUM>, <NUM> toward each other and secured to the locking member <NUM>, thereby providing constant and consistent pressure between the planar surfaces 314a, 324a and the respective inner surfaces of each tissue wall <NUM>, <NUM>. In addition, the outer surfaces of each tissue wall may also be compressed against each other between the proximal and distal retention members <NUM>, <NUM>. The constant and consistent pressure exerted on the inner and outer surfaces of each tissue wall <NUM>, <NUM> may cause selective and localized necrosis at a specific depth of each tissue layer. For example, the depth of necrosis of the first and second tissue walls <NUM>, <NUM> may be limited to the mucosal layers <NUM>, <NUM> to selectively expose and place in contact free ends of the muscularis layers <NUM>, <NUM> along the cylindrical saddle region <NUM> (<FIG>).

In one embodiment, a medical device <NUM> of the present disclosure may establish a long term or permanent open flow or access passage without reorienting (e.g., <FIG>) or compressing (e.g., <FIG>) the tissue walls <NUM>, <NUM> of the first and second body lumens <NUM>, <NUM> along the cylindrical saddle region. Referring to <FIG>, in one embodiment, a medical device <NUM> of the present disclosure may include an elongate body forming a lumen and comprising a proximal portion, a distal portion, a length and a diameter. The elongate body <NUM> may include an elongate tubular configuration (e.g., constrained, unexpanded or delivery configuration; not shown), and a foreshortened configuration (e.g., unconstrained, expanded or deployed configuration) where the proximal portion <NUM> radially expands into a proximal retention member <NUM>, and the distal portion <NUM> radially expands into a distal retention member <NUM>, leaving a cylindrical saddle region <NUM> extending therebetween. A diameter of the cylindrical saddle region <NUM> may be greater than a diameter of the elongate body <NUM> in the elongate tubular configuration. The proximal and distal retention members <NUM>, <NUM> may extend perpendicular to a circumference of the elongate body <NUM> to define respective planar surfaces 414a, 424a. The medical device <NUM> may be positioned between the first and second body lumens by following the exemplary steps outlined in <FIG>, as discussed above, with the exception that the tissue walls <NUM>, <NUM> of the first and second body lumens <NUM>, <NUM> are placed in contact along the cylindrical saddle region <NUM>, e.g., the respective tissue walls are not reoriented by proximal and distal tissue-engaging elements. With the medical device properly positioned between the first and second body lumens <NUM>, <NUM>, the planar surface 414a of the proximal retention member <NUM> my contact and press against the tissue wall <NUM> of the first body lumen <NUM>, and the planar surface 424a of the distal retention member <NUM> may contact and press against the tissue wall <NUM> of the second body lumen <NUM>, to place the body lumens in contact along the cylindrical saddle region <NUM> (<FIG>).

In one embodiment, the medical device <NUM> may include an amount of ferrous material (e.g., formed within the membrane or coating and/or the woven, knitted or braided filament of the elongate body) such that exposure of the patient to an appropriate magnetic field may cause localized vibration of the medical device <NUM>. Establishing the proper frequency of vibrations within the medical device, e.g., by exposing the medical device to the magnetic field generated by a standard MRI machine, may cause the medical device to heat to an appropriate temperature to selectively kill the cells of the mucosal layer <NUM>, <NUM> of the first and second body lumens <NUM>, <NUM>. In addition to selectively killing the cells of the mucosal layer <NUM>, <NUM>, and placing the underlying muscularis layers <NUM>, <NUM> of the first and second body lumens <NUM>, <NUM> in direct contact, heat emitted from the medical device <NUM> may also cauterize the exposed tissue surfaces to facilitate fusion of the muscularis layers (<FIG>).

Referring to Cumulative Effective Minutes at <NUM> Calculations (CEM <NUM>) of <FIG>, radiofrequency induced heating of an implanted medical device may cause cell death when the surrounding tissues are exposed to an elevated temperature (e.g., above <NUM>; body temperature) for an extended period of time. For example, in one embodiment, cell death may occur after one minute of exposure of a medical device heated to <NUM> (e.g., <NUM> above body temperature), or after <NUM> minutes of exposure to a medical device heated to <NUM> (e.g., <NUM> over body temperature). Although <FIG> depict a heat-induced open flow or access passage achieved using a medical device <NUM> that does not include tissue-engaging elements, magnets or slidable filaments, in various embodiments, any or all of the medical devices <NUM>, <NUM>, <NUM> disclosed herein may also include an MRI-induced heating step to further promote the requisite killing of the cells comprising the mucosal layers and place the adjacent muscularis layers of the first and second body lumens in contact. Similarly, in various embodiments, any of the medical device <NUM>, <NUM>, <NUM>, <NUM> disclosed herein may include any combination of the elements (e.g., tissue-engaging elements, magnets or slidable filaments, ferrous materials, etc.) disclosed herein.

The elongate body of any of the medical devices <NUM>, <NUM>, <NUM>, <NUM> depicted in <FIG> may be formed of a woven, knitted or braided filament (e.g., nitinol wire, etc.). The proximal retention member, distal retention member and/or cylindrical saddle region may further include a membrane or coating on an inner and/or outer surface thereof to define a contiguous open interior passage configured for flow (e.g., body fluids, materials, and the like) and/or access therethrough. The coating may comprise a variety of non-degradable and biocompatible polymeric materials (e.g., upon exposure to bodily fluids such as bile), including, for example, silicones, rubbers, polyethylenes, PVDF, Chronoflex® and thermoplastic elastomers such that the coating conforms to the medical device in the elongate tubular and foreshortened configurations. In addition, or alternatively, the woven, knitted or braided filament in any of the various embodiments may be metal filament or polymer filament, and may further include a single filament woven upon itself or multiple filaments woven together. In addition, or alternatively, in one embodiment, the open interior passage may further include one or more valves (e.g., duck-bill valve, slit valve, etc.) moveable between closed and open configurations to block or prevent the flow of fluids therethrough, until the patient or medical professional determines that the valve should be opened (e.g., by inserting a drainage tube). These valves may be positioned anywhere along the open interior passage of the elongate body. Examples of such valves are described in <CIT>. Such valves may comprise a variety of suitable biocompatible and non-degradable materials, including any of the polymers discussed herein, and may be utilized with any of the various embodiments described or otherwise contemplated as within the scope of the present disclosure.

The first and second retention members of any of the medical devices <NUM>, <NUM>, <NUM>, <NUM> depicted in <FIG> may include various configurations, such that one or more of the retention members extend radially at an angle that is not necessarily perpendicular to the elongate body and/or the surfaces are not necessarily planar. For example, one or both of the proximal and distal retention members may extend outward towards an end of the elongate body, back towards a center portion of the elongate body, or change directions in some combination of both. In addition, or alternatively, one or both of the proximal and distal retention members may include an outer diameter di that is greater than an outer diameter d<NUM> of the cylindrical saddle region. For example, outer diameter di may be as much as <NUM>%-<NUM>% greater than an outer diameter d<NUM> of the cylindrical saddle region. By way of non-limiting example, outer diameter di may be approximately <NUM> to approximately <NUM>, and outer diameter d<NUM> may be approximately <NUM> to approximately <NUM>. In various embodiments, the size (e.g., diameter) of the opening formed between the first and second body lumens may be increased or decreased by increasing or decreasing the size (e.g., width) of the proximal and distal retention members (e.g., increasing or decreasing the surface area of the tissue layers compressed between the proximal and distal retention members). In addition, or alternatively, a length of the elongate body in the foreshortened configuration may be at least <NUM>% shorter than a length of the elongate body when in the elongate tubular configuration.

In various embodiments, any of the medical devices <NUM>, <NUM>, <NUM>, <NUM> of the present disclosure may remain in place within the patient for a sufficient amount of time for the muscularis layers <NUM>, <NUM> to join or fuse (e.g., grow together), at which point the medical device may be removed from the patient to leave a long term or permanent open flow, drainage or access passage between the first and second body lumens <NUM>, <NUM>. For example, the medical devices <NUM>, <NUM>, <NUM>, <NUM> may be maintained within the body for a period of days to weeks to establish the requisite level of tissue necrosis between the proximal and distal retention members. The necrotic tissue may eventually slough off to leave a permanent opening defined by the fused muscularis layers.

In various embodiments, any of the medical devices <NUM>, <NUM>, <NUM>, <NUM> of the present disclosure may further include one or more chemicals (e.g., silver nitrate) or anti-proliferative agents embedded on or within the coating of the medical device, including, for example, the cylindrical saddle region and/or the planar surfaces of the proximal and distal retention members, to further facilitate selective killing of the cells of the mucosal layer of the first and second body lumens. In addition, or alternatively, once the medical devices of the present disclosure are removed from the patient, a surgical glue, cryocautery or cryoablation treatment may be applied to the inside diameter of the opening between the first and second body lumens to seal the fused muscularis layers and further prevent the ingrowth of mucosal cells.

In one embodiment, an opening established between first and second body lumens as described herein may be maintained by replacing the medical device used to establish the opening with a permanent implant (e.g., grommet) configured to physically prevent (e.g., block) the opening from closing or re-sealing. Referring to <FIG>, a medical device <NUM> of the present disclosure may include interlockable first and second flexible members <NUM>, <NUM>. For example, the first and second flexible members <NUM>, <NUM> may be formed from a suitable polymeric material (e.g., silicones, rubbers and the like) configured to be deformed, bent, fold, rolled, compressed or otherwise deformed (e.g., within a delivery sheath, etc.) for delivery into a first or second body lumen, and return to the original non-deformed configuration once released from constraint within the respective body lumen. The first flexible member <NUM> may include an outer surface <NUM>, a substantially flat or planer inner surface <NUM>, an outer edge <NUM> with a first circumference and an inner edge <NUM> with a second circumference less than the first circumference, wherein the inner edge <NUM> defines a first opening <NUM> extending between the outer and inner surfaces <NUM>, <NUM>. A plurality of recesses 189a, 189b (e.g., two or more) may be formed within the inner surface <NUM> along the outer edge <NUM> of the first flexible member <NUM>. The second flexible member <NUM> may include an outer surface <NUM>, a substantially flat or planer inner surface <NUM>, an outer edge <NUM> with a first circumference and an inner edge <NUM> with a second circumference less than the first circumference, wherein the inner edge <NUM> defines a second opening <NUM> extending between the outer and inner surfaces <NUM>, <NUM>. A plurality of tabs 199a, 199b (e.g., two or more) may extend from the inner surface <NUM> along the outer edge <NUM> of the second flexible member <NUM>. A cylinder <NUM> coextensive with the second opening <NUM> may also extend from the inner surface <NUM> of the second flexible member <NUM>. Each recess 189a, 189b of the first flexible member <NUM> may be configured to securingly receive a corresponding tab 199a, 199b of the second flexible member <NUM>, e.g., in an interlocking or snap-fit manner, such that the first and second openings <NUM>, <NUM> align to form a contiguous open lumen defined by the cylinder <NUM>, and with the inner surfaces <NUM>, <NUM> of the first and second flexible members <NUM>, <NUM> separated by a predetermined distance.

Referring to <FIG>, in use and by way of example, a medical device <NUM> of the present disclosure may be disposed within a previously formed opening between first and second body lumens <NUM>, <NUM> by loading the first and second flexible members <NUM>, <NUM> within the lumen of a delivery tube in a folded or compressed configuration (not shown). The delivery tube may be advanced through the opening between the first and second body lumens <NUM>, <NUM> such that a distal end of the delivery tube is disposed within the second body lumen <NUM>. The second flexible member <NUM> may then be advanced distally beyond the lumen of the delivery tube such that the second flexible member <NUM> moves to a non-constrained configuration within the second body lumen <NUM>. A separate medical device (not shown) may be advanced through the lumen of the delivery tube, or along an outer surface of the delivery tube, to grasp the second flexible member <NUM> and place the plurality of tabs 199a, 199b in contact with the tissue wall <NUM> of the second body lumen <NUM> such that the second opening <NUM> aligns with the opening between the first and second body lumens <NUM>, <NUM>. The medical device may then be proximally retracted with sufficient force that the tabs 199a, 199b of the second flexible member <NUM> penetrate and extend through the tissue walls <NUM>, <NUM> of the first and second body lumens <NUM>, <NUM>, and the cylinder <NUM> extends through the opening between the first and second body lumens <NUM>, <NUM>. The delivery tube may then be proximally retracted such that the distal end of the delivery tube is disposed within the first body lumen <NUM>. The first flexible member <NUM> may then be advanced distally beyond the lumen of the delivery tube such that the first flexible member <NUM> moves to a non-constrained configuration with the first body lumen <NUM>. While maintaining pressure on the second flexible member <NUM> with the medical device, the first flexible member <NUM> may be placed in contact with the tissue wall <NUM> of the first body lumen <NUM> such that the first opening <NUM> aligns with the opening between the first and second body lumens <NUM>, <NUM>, the recesses 189a, 189b on the inner surface <NUM> of the first flexible member <NUM> align with the tabs 199a, 199b of the second flexible member <NUM> extending into the first body lumen <NUM> and the cylinder <NUM> extends through the opening between the first and second body lumens <NUM>, <NUM>. In one embodiment, the distal end of the delivery tube may be used to place the first flexible member <NUM> in contact with the tissue wall <NUM> of the first body lumen <NUM>. Alternatively, a second medical device (not shown) may be positioned within the first body lumen <NUM> to grasp the first flexible member <NUM> and align the recesses 189a, 189b with the respective ends of the tabs 199a, 199b. The first and second flexible members <NUM>, <NUM> may then be advanced toward each other such that the tabs 199a, 199b extending from the inner surface <NUM> of the second flexible member <NUM> engage the corresponding recesses 189a, 189b on the inner surface <NUM> of the second flexible member <NUM>, thereby aligning the first and second openings <NUM>, <NUM> of the first and second flexible members <NUM>, <NUM> with the opening between the first and second body lumens. A predetermined distance between the inner surfaces <NUM>, <NUM> of the first and second flexible members <NUM>, <NUM> may allow the tissue walls <NUM>, <NUM> of the first and second body lumens to be maintained in a non-compressed state (e.g., one that does not induce tissue necrosis) throughout the duration of the medical device being implanted within the patient. Although <FIG> depicts two tabs 199a, 199b and two corresponding recesses 189a, 189b disposed on opposite sides of the ends of their respective flexible members <NUM>, <NUM>, in various embodiments, any number or tabs and recesses may be disposed in a variety of patterns, orientations and/or configurations.

Referring to <FIG>, to minimize trauma to the tissue layers of the first and second body lumens, in one embodiment, a medical device <NUM> of the present disclosure may include interlockable first and second flexible members <NUM>, <NUM>, as discussed above. A cylinder <NUM> coextensive with the second opening <NUM> may extend from the inner surface <NUM> of the second flexible member <NUM>. A free end of the cylinder may include series of tabs (or a single continuous or circular tab) configured to extend through an opening between the first and second body lumens and engage a corresponding recess <NUM> (e.g., circular groove) surrounding the first opening <NUM> of the first flexible member <NUM> in an interlocking or snap-fit manner, such that the first and second openings <NUM>, <NUM> align to form a contiguous open lumen defined by the cylinder <NUM>, and with the inner surfaces <NUM>, <NUM> of the first and second flexible members <NUM>, <NUM> separated by a predetermined distance.

In addition, in various embodiments, the first and second flexible members <NUM>, <NUM> are not limited to being disposed within the first and second body lumens. For example, the first flexible member may be disposed within the second body lumen to receive the tabs of the second flexible member positioned within the first body lumen.

Claim 1:
A medical device (<NUM>), comprising:
an elongate body (<NUM>) forming a lumen and comprising a proximal portion (<NUM>), a distal portion (<NUM>), a length and a diameter;
the elongate body having an elongate tubular configuration, and a deployed configuration where the proximal portion (<NUM>) expands into a proximal retention member (<NUM>) and the distal portion (<NUM>) expands into a distal retention member (<NUM>) leaving a cylindrical saddle region (<NUM>) therebetween;
a plurality of proximal tissue-engaging elements (<NUM>) disposed along an outer surface of the cylindrical saddle region (<NUM>) distal to the proximal retention member (<NUM>); and
a plurality of distal tissue-engaging elements (<NUM>) disposed along an outer surface of the cylindrical saddle region (<NUM>) proximal to the distal retention member (<NUM>).