METHODS OF MAKING AN EXPANDABLE SHEATH
Disclosed herein are expandable introducer sheaths and methods of making and using the same. The sheaths minimize trauma to a patient's vasculature by allowing for temporary expansion of a portion of the sheath to accommodate passage of a delivery system for a cardiovascular device, then return to a non-expanded state after the passage of the device. The sheath includes an elongated annular member through which the cardiovascular device and its delivery system pass. In an embodiment, the annular inner member can be formed by coextruding a first and second material. The first material includes a fold, and the second material radially spaces the different parts of the fold from each other during fabrication and provides support for maintaining the tubular structure. The second material is removed once the coextrusion process is complete.
Latest EDWARDS LIFESCIENCES CORPORATION Patents:
This application is a continuation application of U.S. Non-provisional application Ser. No. 16/514,021, filed Jul. 17, 2019, which claims the benefit of U.S. Provisional Application No. 62/702,993, filed Jul. 25, 2018, where each of above-referenced applications are incorporated by reference in its entirety for all purposes.
TECHNICAL FIELDThe present application is directed to a sheath for use with catheter-based technologies for repairing and/or replacing heart valves, as well as for delivering an implant, such as a prosthetic valve to a heart via the patient's vasculature.
BACKGROUNDEndovascular delivery catheter assemblies are used to implant prosthetic devices, such as a prosthetic heart valve, at locations inside the body that are not readily accessible by surgery or where less invasive surgery is desirable. For example, aortic, mitral, tricuspid, and/or pulmonary prosthetic valves can be delivered to a treatment site using minimally invasive surgical techniques, including transcatheter delivery methods.
An introducer sheath can be used to safely introduce a delivery apparatus into a patient's vasculature (e.g., the femoral artery). An introducer sheath generally has an elongated sleeve that is inserted into the vasculature and a housing that contains one or more sealing valves that allow a delivery apparatus to be placed in fluid communication with the vasculature with minimal blood loss. A conventional introducer sheath typically requires a tubular loader to be inserted through the seals in the housing to provide an unobstructed path through the housing for the prosthetic implant, such as a heart valve mounted on a balloon catheter. A conventional loader extends from the proximal end of the introducer sheath, and therefore decreases the available working length of the delivery apparatus that can be inserted through the sheath and into the body.
Conventional methods of accessing a vessel, such as a femoral artery, prior to introducing the delivery system include dilating the vessel using multiple dilators or sheaths that progressively increase in diameter. This repeated insertion and vessel dilation can increase the amount of time the procedure takes, as well as the risk of damage to the vessel.
Radially expanding intravascular sheaths reduce the overall profile of the sheath to reduce risk of damage to the vessel. Such sheaths tend to have complex mechanisms, such as ratcheting mechanisms that maintain the shaft or sheath in an expanded configuration once a device with a larger diameter than the sheath's original diameter is introduced.
However, delivery and/or removal of prosthetic devices and other material to or from a patient still poses a risk to the patient. Furthermore, accessing the vessel remains a challenge due to the relatively large profile of the delivery system that can cause longitudinal and radial tearing of the vessel during insertion. The delivery system can additionally dislodge calcified plaque within the vessels, posing an additional risk of clots caused by the dislodged plaque. The addition of radially expanding properties can also hinder a practitioner's ability to push the sheath without it bending or kinking. Thus, there remains a need for further improvements in introducer sheaths for endovascular systems used for implanting heart valves and other prosthetic devices.
Improved introducer sheaths are described in U.S. patent application Ser. No. 14/880,109, which is hereby incorporated by reference in its entirety. This sheath advantageously incorporates a longitudinal fold that can be unfolded to allow for radial expansion as an implant passes through. An outer, elastic tubular layer, surrounding the folded inner layer, can urge the expanded inner layer back to the folded configuration. Methods of making an inner layer with a longitudinal fold conventionally involve annealing operations to form the folded profile. The annealing operations are time consuming an require expensive heat shrink tube consumables. There are several thermal bonding operations that form the transition from folded low profile cross section to the large proximally located cross section that is required to mate with the hub/hemostasis valve housing. These operations add time, complexity, and incorporate potential failure locations at the bond joints.
SUMMARYDisclosed herein are expandable introducer sheaths and methods of making and using the same. The sheaths are adapted to temporarily expand a portion of the sheath to allow for the passage of a delivery system for a cardiovascular device, then return to a non-expanded state after the passage of the system. The sheath includes an elongated annular member through which the cardiovascular device and its delivery system pass. In an embodiment, the annular inner member can be formed by coextruding a first and second material. The first material includes a fold, and the second material radially spaces the different parts of the fold from each other during fabrication and provides support for maintaining the tubular structure. The second material is removed once the coextrusion process is complete.
Disclosed herein is a method of making an expandable sheath. The method includes coextruding a first material and a second material. The first coextruded material defines an elongated annular member having a circumferentially extending thick wall portion. The thick wall portion has a first longitudinally extending end and a second longitudinally extending end. The second longitudinally extending end overlaps the first longitudinally extending end to create a folded overlapping segment. The thick wall portion of the annular member is integrally connected to a circumferentially extending thin wall portion. The thin wall portion extends between the first longitudinally extending end and the second longitudinally extending end of the thick wall portion. The first longitudinally extending end is radially closer to a central axis of the elongated annular member than the thin wall portion, and the second longitudinally extending end is radially farther from the central axis the thin wall portion.
The second coextruded material radially spaces the thin wall portion from the thick wall portion in during the coextrusion process. After the coextrusion is finished, the second coextruded material is then removed (by force, for example). The removal of the second extruded material allows for sliding movement of the first longitudinal end relative to the second longitudinal end and radial expansion of the elongated annular member. The second coextruded material can be removed by applying a force to at least one of the first and the second coextruded materials. The second coextruded material can be removed by applying a thermal treatment to at least one of the first and the second coextruded materials. The second coextruded material can be removed by applying a chemical treatment to at least one of the first and the second coextruded materials.
In some embodiments, the second coextruded material extends along the entire circumferential width of the overlapping segment. It can continue to extend circumferentially away from the overlapping segment. Two separate layers of the second coextruded material can be utilized. In some embodiments, a first layer of the second coextruded material is positioned between the first longitudinally extending end and the thin wall portion. In some embodiments, the first layer of the second coextruded material extends circumferentially away from the first longitudinally extending end. The first layer can extend circumferentially along an outer surface of the elongated annular member. A second layer of the second coextruded material is positioned between the second longitudinally extending end and the thin wall portion. The second layer of the second coextruded material can extend circumferentially away from the second longitudinally extending end. In some embodiments, the second layer of the second coextruded material extends circumferentially along an inner surface of the elongated annular member.
In some embodiments, the second coextruded material extends along an inner surface and an outer surface of the elongated member. The second coextruded material can extend around the entire circumference of the inner surface of the elongated member. The second coextruded material can also extend around the entire circumference of the outer surface of the elongated member.
In some embodiments of the method, a taper tube is coextruded near the proximal end of the annular member. The taper tube can have a diameter greater than a diameter of the elongated member. The taper tube is added as part of the coextrusion process, and therefore does not require the use of bonding processes (e.g., thermal bonding, chemical bonding, mechanical bonding). Finally, the annular member can be covered by an elastic outer layer which returns the annular member to a folded configuration after expansion (for example, after an implant passes through).
In the drawings, like reference numbers and designations in the various drawings indicate like elements.
The following description of certain examples of the inventive concepts should not be used to limit the scope of the claims. Other examples, features, aspects, embodiments, and advantages will become apparent to those skilled in the art from the following description. As will be realized, the device and/or methods are capable of other different and obvious aspects, all without departing from the spirit of the inventive concepts. Accordingly, the drawings and descriptions should be regarded as illustrative in nature and not restrictive.
For purposes of this description, certain aspects, advantages, and novel features of the embodiments of this disclosure are described herein. The described methods, systems, and apparatus should not be construed as limiting in any way. Instead, the present disclosure is directed toward all novel and nonobvious features and aspects of the various disclosed embodiments, alone and in various combinations and sub-combinations with one another. The disclosed methods, systems, and apparatus are not limited to any specific aspect, feature, or combination thereof, nor do the disclosed methods, systems, and apparatus require that any one or more specific advantages be present or problems be solved.
Features, integers, characteristics, compounds, chemical moieties, or groups described in conjunction with a particular aspect, embodiment or example of the invention are to be understood to be applicable to any other aspect, embodiment or example described herein unless incompatible therewith. All of the features disclosed in this specification (including any accompanying claims, abstract, and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive. The invention is not restricted to the details of any foregoing embodiments. The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract, and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.
It should be appreciated that any patent, publication, or other disclosure material, in whole or in part, that is said to be incorporated by reference herein is incorporated herein only to the extent that the incorporated material does not conflict with existing definitions, statements, or other disclosure material set forth in this disclosure. As such, and to the extent necessary, the disclosure as explicitly set forth herein supersedes any conflicting material incorporated herein by reference. Any material, or portion thereof, that is said to be incorporated by reference herein, but which conflicts with existing definitions, statements, or other disclosure material set forth herein will only be incorporated to the extent that no conflict arises between that incorporated material and the existing disclosure material.
As used in the specification and the appended claims, the singular forms “a,” “an” and “the” include plural referents unless the context clearly dictates otherwise. Ranges may be expressed herein as from “about” one particular value, and/or to “about” another particular value. When such a range is expressed, another aspect includes from the one particular value and/or to the other particular value. Similarly, when values are expressed as approximations, by use of the antecedent “about,” it will be understood that the particular value forms another aspect. It will be further understood that the endpoints of each of the ranges are significant both in relation to the other endpoint, and independently of the other endpoint.
“Optional” or “optionally” means that the subsequently described event or circumstance may or may not occur, and that the description includes instances where said event or circumstance occurs and instances where it does not.
Throughout the description and claims of this specification, the word “comprise” and variations of the word, such as “comprising” and “comprises,” means “including but not limited to,” and is not intended to exclude, for example, other additives, components, integers or steps. “Exemplary” means “an example of” and is not intended to convey an indication of a preferred or ideal aspect. “Such as” is not used in a restrictive sense, but for explanatory purposes.
Disclosed herein are expandable introducer sheaths and methods of making and using the same. As will be described in further detail below, the expandable sheaths 1 are adapted to allow for temporary expansion of a portion of the sheath to accommodate the passage of a delivery system for a cardiovascular device, then return to a non-expanded state, or “recover” after the passage of the delivery system and device.
The expandable introducer sheath 1 is adapted to allow for temporary radial expansion of a portion of the sheath to accommodate the passage of a delivery system for a cardiovascular device (e.g., prosthetic heart valve 212) and to then return to a non-expanded state after the passage of the delivery system with its prosthetic device. The expandable sheath 1 includes an elongated annular member 10 through which the delivery system and prosthetic heart valve 212 pass. As will be described in more detail below, the annular member 10 of the expandable sheath 1 can include longitudinally extending channels 12, 14 that facilitate the sheath's expansion for passage of the prosthetic heart valve 212. The channels 12, 14 are positioned such that upon expansion of the annular member 10 certain contact surfaces 22, 24 are brought into contact with adjacent surfaces of the delivery apparatus 210, thereby reducing friction between the annular member 10 and the passing structure. In some embodiments, the radial expansion of the expandable annular member 10 at any given portion along its length is due to the ability of base 20 and/or bridge members 30 of the annular member 10 to rotate. The rotation of these sections reduces the surface/contact area of the annular member 10 thereby reducing friction with the passing structure. The expandable sheath 1 can include an elastic outer layer 50. In some embodiments, the outer layer 50 can compress the annular member 10 towards a non-expanded configuration.
As illustrated in
The inward and outward extending channels 12, 14 alternate in inward versus outward directionality, such that each channel of a selected set/direction is positioned circumferentially between two channels of the other set/direction (i.e., each inward extending channel 12 is positioned circumferentially between two outward extending channels 14, each outward extending channel 14 is positioned circumferentially between two inward extending channels 12).
As depicted in
The inward and outward extending channels 12, 14 extend a certain depth (d) into the wall thickness (t) of the annular member 10. For example, as illustrated in
The inward and outward extending channels 12, 14 can also define a width (w) measured along the length/depth of the channel. The width (w) can be defined between the sidewall of the corresponding bridge member 30 and base member 20, i.e., between side wall 13 and side wall 15. As illustrated in
The shape of the inward and outward extending channels 12, 14 can remain constant or vary around the circumference of the annular member 10. As depicted in
In the embodiment shown in
As described above, the annular member 10 and elastic outer layer 50 of the sheath 1 are designed to locally expand as the prosthetic device 212 is passed through the interior lumen of the sheath 1 and then substantially return to their original shape once the prosthetic device has passed through that portion of the sheath 1. That is, in the non-expanded state the outer diameter of the annular member 10 and outer layer 50 can be substantially constant across the length of the sheath 1 from the proximal end 3 to the distal end 5. As the prosthetic device 212 passes through the interior lumen of the sheath 1, the portion of the annular member 10 and outer layer proximate the prosthetic device 212 expand radially, with the remaining length/portion of the annular member 10 and outer layer 50 in a substantially non-expanded state. Once the device has passed through a portion of the lumen of the sheath 1, that portion of the sheath 1 can substantially return to its original shape and size.
To achieve expansion, the orientation of the base members 20 and bridge members 30 changes. As illustrated in
As illustrated in
In transition back to the non-expanded state, the base members 20 and bridge members 30 move back to their original configuration/orientation. The transition back to the non-expanded state can be facilitated by the inclusion of an elastic outer layer 50 that extends over the elongated annular member 10. The outer layer 50 comprises a material having a lower elastic modulus than the annular member 10, which enables the outer layer 50 to force the annular member 10 back into the non-expanded state after passage of the cardiovascular device. The annular member 10 can be made of a more lubricious material than the outer layer 50. For example, the outer layer 50 can be made of, or incorporate, polyurethane, silicone, and/or rubber, and the annular member 10 can be made of, or incorporate, high density polyethylene, polytetrafluoroethylene, and/or other fluoropolymers.
Similar to the annular member 10 depicted in
As described above, the annular member 10 and the elastic outer layer 50 of the sheath 1 are designed to locally expand in a radial direction between a non-expanded and an expanded state as the prosthetic device 212 is passed through the interior lumen of the sheath 1.
As illustrated in
Similar to the annular member 10 depicted in
As described above, the annular member 10 and the elastic outer layer 50 are designed to locally expand in a radial direction between a non-expanded and an expanded state as the prosthetic device 212 is passed through the interior lumen of the sheath 1.
As illustrated in
Similar to the annular members 10 depicted in
As described above, the annular member 10 and the elastic outer layer 50 are designed to locally expand in a radial direction between a non-expanded and an expanded state as the prosthetic device 212 is passed through the inner lumen of the sheath 1.
As illustrated in
In the non-expanded state, the base members 20 and bridge members 30 can define a curvilinear shape in cross-section. For example, as depicted in
Similar to the annular members 10 depicted in
As described above, the annular member 10 and the elastic outer layer 50 of the sheath 1 are designed to locally expand in a radial direction between a non-expanded and an expanded state as the prosthetic device 112 is passed through the interior lumen of the sheath 1.
As illustrated in
As illustrated in
Sheaths of the present disclosure can be used with various methods of introducing a prosthetic device into a patient's vasculature. Generally, during use, the expandable sheath 1 is passed through the skin of patient (usually over a guidewire) such that the distal end region of the expandable sheath 1 is inserted into a vessel, such as a femoral artery, and then advanced to a wider vessel, such as the abdominal aorta. The delivery apparatus 210 is then inserted through the expandable sheath 1. The prosthetic device is then delivered to the implantation site and implanted within the patient. During the advance of the prosthetic device through the expandable sheath 1, the device and its delivery system exerts a radially outwardly directed force on the portion of the annular member 10, the annular member 10 exerts a corresponding radially outwardly directed force on the outer layer 50, causing both the annular member 10 and the outer layer 50 to expand locally to accommodate the profile of the device. The expansion of the annular member 10 widens the longitudinally extending channels 12, 14 of the annular member and causes the movement of longitudinally extending contact surfaces 22, 24 toward the inner and outer surfaces 16, 18 of the annular member 10.
As the prosthetic device and its delivery system passes through the expandable sheath 1, the expandable sheath 1 recovers. That is, it returns to its original, non-expanded configuration. In some embodiments, this is facilitated by outer layer 50, which has a lower elastic modulus than annular member 10. The outer layer 50 moves the contact surfaces 22, 24 of the annular member 10 away from the inner and outer surfaces after the passage of the prosthetic valve 212.
As described above, the expandable sheath 1 can be used to deliver, remove, repair, and/or replace a prosthetic device. In one example, the expandable sheath 1 described above can be used to deliver a tissue heart valve to a patient. For example, a tissue heart valve (in a crimped state) can be placed on the distal end portion of an elongated delivery apparatus and inserted into the sheath. Next, the delivery apparatus and crimped heart valve can be advanced through the patient's vasculature to the treatment site, where the valve is implanted.
Beyond transcatheter heart valves, the expandable sheath 1 can be useful for other types of minimally invasive surgery, such as any surgery requiring introduction of an apparatus into a subject's vessel. For example, the expandable sheath 1 can be used to introduce other types of delivery apparatus for placing various types of intraluminal devices (e.g., stents, stented grafts, balloon catheters for angioplasty procedures, etc.) into many types of vascular and non-vascular body lumens (e.g., veins, arteries, esophagus, ducts of the biliary tree, intestine, urethra, fallopian tube, other endocrine or exocrine ducts, etc.).
In some embodiments, the second material 62 is a sacrificial material. For example, the ribbons 64, 66 of the second material 62 shown in
However, some embodiments, such as the one shown in
Some methods include a step of covering the annular member 10 with the outer layer after coextrusion. As discussed above, the outer layer 50 is formed of, or incorporates, a material with a lower elastic modulus than the annular member 10.
Additionally, the sheath 1 can comprise a soft distal tip 80 at the distal end 5. The soft tip 80 can be provided with a lower hardness than the other portions of the sheath 1. In addition to the method of making the expandable sheath described above, a method of making a distal tip 80 of an expandable sheath 1 is demonstrated in the flow chart of
Next, a portion of the distal tube 82 is pinched to create a longitudinally extending outer crease 84. The pinched portion is folded over an outer surface of the distal tube 82 in a circumferential direction, creating a longitudinally extending flap 86 that is bounded by the outer crease 84 and a longitudinally extending inner crease 85. The inner crease 85 of the flap 86 is cut in a longitudinal direction from the distal edge 83 of the distal tube 82 to a proximally spaced point along the longitudinal axis of the distal tube 82. This creates a longitudinally extending inner edge 87. The flap 86 is cut circumferentially from the outer crease 84 to the inner crease 85 at the proximally spaced point, such that the longitudinal cut of the inner crease 85 meets the circumferential cut at the proximally spaced point. The inner edge 87 of the flap is then extended in a circumferential direction around the outer surface 81 of the distal tube 82 and adhered to the outer surface 81.
In some embodiments, such as the one shown in
The thick wall portion 162 of the annular member 10, as in the illustrated embodiment of
The thin wall portion 164 extends between the first and second ends 166, 168 of the thick wall portion 162 which together define the tubular shape of the annular member 10. Central lumen 138 extends longitudinally within that tubular shape.
As will be described in more detail below, the foldable annular member 10 shown in
As shown in
The second material 167 is coextruded between and in contact with the thick and thin wall portions 162, 164, in a manner that radially spaces the thin wall portion 164 from the thick wall portion 162. The second material 167 can be coextruded in two separate layers/portions to form the overlapping structure of the thick and think wall portions 162, 164. A first layer 172 of the second material 167 is positioned between the first longitudinally extending end 166 and the thin wall portion 164, and a second layer 174 of the second material 167 is positioned between the second longitudinally extending end 168 and the thin wall portion 164. Each of the first and second layers 172, 174 of the second material 167 have a generally C-shape in cross section. In some embodiments, the second material 167 extends circumferentially along the entire overlapping segment 170 and continues to extend away from the overlapping segment 170 in either direction, as shown in
After coextrusion, the second material 167 can be removed. In some implementations, the second material 167 can be physically removed from the first material 165 by force, for example, by applying a force (axial and/or radial) to at least one of the first and/or second materials 165, 167. The second material 167 can be formed of a material that does not adhere to the first material 165 during the coextrusion process, making its physical removal relatively easy. In other embodiments, the first material and second material can have different chemical properties or melting points, such that chemical or thermal treatments may be used to remove the second material 167 from the first material 165. While the first material 165 could be, or could incorporate, HDPE, the second material 167 could be, or could incorporate, nylon, polyethylene terephthalate, PA12, and/or polybutylene terephthalate, for example. The removal of the second material 167 enables the first longitudinal end 166 to slide relative to the second longitudinal end 168, such that the annular member 10 can be radially expanded.
In some embodiments, the coextrusion process used to form the sheath shown in
The use of the processing methods described above to form a folded sheath such as the one shown in
The corresponding structures, materials, acts, and equivalents of all means or step plus function elements in the claims below are intended to include any structure, material, or act for performing the function in combination with other claimed elements as specifically claimed. The description of the present invention has been presented for purposes of illustration and description, but is not intended to be exhaustive or limited to the invention in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the invention. The implementation was chosen and described in order to best explain the principles of the invention and the practical application, and to enable others of ordinary skill in the art to understand the invention for various implementations with various modifications as are suited to the particular use contemplated. It is intended that the scope of the present invention herein disclosed should not be limited by the particular disclosed embodiments described above, but should be determined only by a fair reading of the claims that follow.
Claims
1. A method of making an expandable sheath comprising:
- coextruding a first material and a second material; and
- removing the second coextruded material from the first coextruded material;
- wherein the first coextruded material defines an annular member; and
- wherein the second coextruded material defines a first and a second set of longitudinally extending ribbons.
2. The method of claim 1, wherein the second coextruded material does not adhere to the first coextruded material.
3. The method of claim 1, wherein the second coextruded material comprises nylon, polyethylene terephthalate, polybutylene terephthalate, or a combination thereof.
4. The method of claim 1, wherein the first and second set of longitudinally extending ribbons form inward and outward extending channels of the annular member, wherein the first set of ribbons extends inwardly from an outer surface toward an inner surface of the annular member forming inward extending channels in the annular member, wherein the second set of ribbons extends outwardly from an inner surface toward an outer surface of the annular member forming outward extending channels in the annular member.
5. The method of claim 4, wherein each ribbon of a selected set is positioned circumferentially between two ribbons of the other set.
6. The method of claim 1, wherein the second coextruded material is removed from the first coextruded material by at least one of applying a thermal treatment to at least one of the first and the second coextruded materials, or applying a chemical treatment to at least one of the first and the second coextruded materials.
7. The method of claim 1, further comprising coextruding the first and second material with a third material, wherein the third material is in contact with a portion of the first coextruded material and a portion of the second coextruded material, where the third coextruded material adheres to both the first and the second coextruded materials and wherein the second coextruded material does not adhere to the first coextruded material.
8. The method of claim 1, further comprising adding a taper tube, at least a portion of the taper tube having a diameter greater than a diameter of the annular member, where the taper tube is added without using a thermal bonding process.
9. The method of claim 1, further comprising adding a taper tube, at least a portion of the taper tube having a diameter greater than a diameter of the annular member, where the taper tube is added without using a bonding process.
10. The method of claim 1, further comprising adding a taper tube, at least a portion of the taper tube having a diameter greater than a diameter of the annular member, where the taper tube is added as part of the coextrusion process.
11. The method of claim 1, further comprising covering the annular member with an outer layer comprising a material having a lower elastic modulus than the annular member, where the annular member and the outer layer expand in a radial direction between an unexpanded state and an expanded state.
12. The method of claim 1, wherein the annular member comprises a plurality of base members arranged around a circumference of the annular member, where the plurality of base members abut a plurality of bridge members extending between opposing pairs of base members,
- wherein the plurality of base members and the plurality of bridge members have rotational degrees of freedom around a longitudinal axis of the annular member,
- wherein each of the plurality of bridge members has a first end coupled to a radially inward end of a corresponding one of the plurality of base members, and a second end coupled to a radially outward end of the corresponding one of the plurality of base members.
13. An expandable sheath comprising:
- an annular member including: inward extending channels extending channel extending from an outer surface of the annular member toward an inner surface of the annular member, and outward extending channels extending outwardly from the inner surface toward the outer surface of the annular member,
- wherein the annular member configured to locally expand from an unexpanded state in which the annular member has a first diameter to an expanded state in which the annular member has a second, larger, diameter,
- wherein upon expansion of the annular member, a width of each of the inward extending channels and outward extending channels increases.
14. The expandable sheath of claim 13, wherein the annular member comprises a first material,
- wherein the expandable sheath further comprises a second material that is coextruded with the annular member, the second material defining a first and a second set of longitudinally extending ribbons that occupy the inward and outward extending channels of the annular member.
15. The expandable sheath of claim 14, wherein each ribbon of a selected set is positioned circumferentially between two ribbons of the other set.
16. The expandable sheath of claim 14, wherein the second material does not adhere to the first material.
17. The expandable sheath of claim 14, wherein the second coextruded material is removable from the first coextruded material by applying at least one of a thermal treatment to at least one of the first and the second coextruded materials, or by applying a chemical treatment to at least one of the first and the second coextruded materials.
18. The expandable sheath of claim 14, further comprising a third material coextruded with the first and second material, wherein the third material is in contact with a portion of the first coextruded material and a portion of the second coextruded material, where the third coextruded material adheres to both the first and the second coextruded materials and wherein the second coextruded material does not adhere to the first coextruded material.
19. The expandable sheath of claim 14, further comprising:
- an outer layer covering the annular member configured to locally expanded between the unexpanded state and the expanded state, the outer layer comprising a material having a lower elastic modulus than the annular member.
20. The expandable sheath of claim 14, wherein the annular member comprises a plurality of base members arranged around a circumference of the annular member, wherein the plurality of base members abut a plurality of bridge members extending between opposing pairs of base members,
- wherein the plurality of base members and the plurality of bridge members have rotational degrees of freedom around a longitudinal axis of the annular member,
- wherein each of the plurality of bridge members has a first end coupled to a radially inward end of a corresponding one of the plurality of base members, and a second end coupled to a radially outward end of the corresponding one of the plurality of base members.
Type: Application
Filed: Sep 7, 2023
Publication Date: Dec 28, 2023
Applicant: EDWARDS LIFESCIENCES CORPORATION (Irvine, CA)
Inventors: Erik Bulman (Lake Forest, CA), Duy Nguyen (Corona, CA), Kim D. Nguyen (Irvine, CA)
Application Number: 18/243,495