Implantable medical device with seal to accommodate irregular apertures

Abstract

An implantable medical device including an expandable framework expandable between a collapsed configuration for delivery and an expanded configuration for deployment, the expandable framework including an outer periphery defined by the expandable framework. The cover spans at least a portion of the expandable framework. An expandable element is secured relative to the periphery, the expandable element adapted to seal an irregularly shaped aperture against an irregular body opening, such as a patient's LAA (left atrial appendage).

Description

[0001] Cross - reference to related applications

[0002] This application claims the benefit of priority to U.S. Provisional Application No. 63 / 419,403, filed on October 26, 2022, the entire disclosure of which is incorporated herein by reference. Technical Field

[0003] The present disclosure generally relates to medical devices, and more particularly, to medical devices suitable for percutaneous medical procedures, which include implantation into the left atrial appendage (LAA) of the heart. Background Art

[0004] The left atrial appendage is a small organ attached to the left atrium of the heart. During normal heart function, when the left atrium contracts and forces blood into the left ventricle, the left atrial appendage contracts and forces blood into the left atrium. The ability of the left atrial appendage to contract helps to improve the filling of the left ventricle, thus playing a role in maintaining cardiac output. However, in patients with atrial fibrillation, the left atrial appendage may not contract or empty properly, resulting in pooling of stagnant blood inside the left atrial appendage, which may lead to the formation of unwanted thrombi in the left atrial appendage.

[0005] Thrombi formed in the left atrial appendage may break off from this area and enter the bloodstream. Thrombi migrating through the blood vessels may eventually block smaller downstream blood vessels, leading to a stroke or a heart attack. Clinical studies have shown that the majority of blood clots in patients with atrial fibrillation originate from the left atrial appendage. As a treatment method, medical devices have been developed to deploy and close the left atrial appendage. In known medical devices and methods, each has certain advantages and disadvantages. There is a continuing need to provide alternative medical devices and alternative methods of manufacturing and using medical devices. Summary of the Invention

[0006] The present disclosure provides designs, materials, manufacturing methods, and use alternatives for medical devices. An example can be found in an implantable medical device. The implantable medical device includes an expandable frame that can expand between a contracted configuration for delivery and an expanded configuration for deployment. The expandable frame includes a periphery defined by the expandable frame. A covering spans at least a portion of the expandable frame. An expandable element is fixedly attached relative to the periphery and is adapted to seal against an irregular body opening.

[0007] Alternatively or additionally, the irregular body opening may include the orifice of the patient's LAA (left atrial appendage).

[0008] Alternatively or additionally, the expandable element may include a plurality of bag filters arranged around the periphery.

[0009] Alternatively or additionally, each of the plurality of bag filters may have an open end and a closed end, and each of the plurality of bag filters may be arranged around the outer periphery such that the open ends face one direction and the closed ends face the opposite direction.

[0010] Alternatively or additionally, each of the plurality of bag filters may have an open end and a closed end, and each of the plurality of bag filters may be arranged around the outer periphery in an alternating manner, wherein the open ends of the bag filters are arranged close to the closed ends of adjacent bag filters.

[0011] Alternatively or additionally, at least some of the plurality of bag filters may have two open ends and include one-way valves that restrict blood flow therethrough.

[0012] Alternatively or additionally, at least some of the plurality of bag filters may include a coagulant disposed within the bag filter.

[0013] Alternatively or additionally, the expandable element may include a corrugated three-layer element extending around the outer periphery, the corrugated three-layer element including an inner layer, an outer layer, and intermediate middle layers alternating between being attached to the inner layer and being attached to the outer layer.

[0014] Alternatively or additionally, the corrugated three-layer element may include a coagulant.

[0015] Alternatively or additionally, the expandable element may include an all-directional valved mesh.

[0016] Alternatively or additionally, the implantable medical device may include a LAAC (left atrial appendage closure) device.

[0017] Another example may be found in a LAAC (left atrial appendage closure) device that is adapted to fit within an irregular orifice of a patient's LAA (left atrial appendage). The LAAC device includes an expandable frame that is expandable between a contracted configuration for delivery and an expanded configuration for deployment, the expandable frame including an outer periphery defined by the expandable frame. A covering spans at least a portion of the expandable frame. The expandable element is adapted to seal against the irregular orifice of the patient's LAA.

[0018] Alternatively or additionally, the expandable element may include a coagulant.

[0019] Alternatively or additionally, the expandable element may include an inflatable member.

[0020] Alternatively or additionally, the expandable element may include a plurality of bag filters.

[0021] Another example can be found in a LAAC (Left Atrial Appendage Closure) device that is adapted to fit within an irregular orifice of a patient's LAA (Left Atrial Appendage). The LAAC device includes an expandable framework that is expandable between a contracted configuration for delivery and an expanded configuration for deployment, the expandable framework including a perimeter defined by the expandable framework. A covering spans at least a portion of the expandable framework. A plurality of bag filters are disposed around the perimeter.

[0022] Alternatively or additionally, each of the plurality of bag filters can have an open end and a closed end, and each of the plurality of bag filters can be disposed around the perimeter such that the open ends face one direction and the closed ends face the opposite direction.

[0023] Alternatively or additionally, each of the plurality of bag filters can have an open end and a closed end, and each of the plurality of bag filters can be disposed around the perimeter in an alternating manner, where the open ends of the bag filters are disposed adjacent to the closed ends of adjacent bag filters.

[0024] Alternatively or additionally, at least some of the plurality of bag filters can have two open ends and include a one-way valve that restricts blood flow therethrough.

[0025] Alternatively or additionally, at least some of the plurality of bag filters can include a coagulant disposed within the bag filter.

[0026] The foregoing summary of some embodiments is not intended to describe every disclosed embodiment or every implementation of the present disclosure. The following figures and detailed description more particularly exemplify these embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The present invention can be more fully understood in connection with the following detailed description of various embodiments of the invention considered in conjunction with the accompanying drawings, in which:

[0028] Figure 1 is a partial cross-sectional view of the LAA (Left Atrial Appendage);

[0029] Figure 2 is a perspective view of an exemplary LAAC (Left Atrial Appendage Closure) device without showing the covering;

[0030] Figure 3 is Figure 2 a perspective view of the exemplary LAAC device including the covering;

[0031] Figure 4 is a schematic cross-sectional view of the exemplary LAAC device;

[0032] Figure 5 is a schematic enlarged view of several filter bags;

[0033] Figure 6 Schematic diagram of an expandable element that utilizes Figure 5 a filter bag and can be combined with a LAAC device;

[0034] Figure 7 Schematic diagram of an expandable element that utilizes Figure 5 a filter bag and can be combined with a LAAC device;

[0035] Figure 8 Schematic diagram of an exemplary LAAC device with an expandable element, the shown LAAC device being disposed within the LAA;

[0036] Figure 9 Schematic diagram of an exemplary LAAC device with a corrugated triple - layer expandable element;

[0037] Figure 10 is Figure 9 Schematic diagram of the deployment of the shown exemplary LAAC device within an irregular orifice;

[0038] Figure 11 Schematic diagram of an exemplary valved mesh; and

[0039] Figure 12A 、 Figure 12B and Figure 12C collectively provide a view of exemplary membrane materials that can be used as overlays on the LAAC devices described herein.

[0040] While the present disclosure may have various modifications and alternative forms, details thereof have been shown by way of example in the drawings and will be described in detail. However, it should be understood that the intention is not to limit the present disclosure to the particular embodiments described. On the contrary, the present disclosure is intended to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure. Detailed Description

[0041] The following description should be read with reference to the drawings, which are not necessarily to scale, where like reference numerals indicate like elements in several views. The detailed description and the drawings are intended to illustrate rather than limit the present disclosure. Those skilled in the art will recognize that the various elements described and / or shown can be arranged in various combinations and configurations without departing from the scope of the present disclosure. The detailed description and the drawings illustrate exemplary embodiments of the present disclosure. However, for clarity and ease of understanding, although not every feature and / or element may be shown in each drawing, these features and / or elements can be understood to be present nonetheless, unless otherwise stated.

[0042] For the terms defined below, these definitions will apply unless a different definition is given in the claims or elsewhere in this specification.

[0043] Whether or not explicitly stated, all numerical values herein are assumed to be modified by the term "about". The term "about" generally refers to a range of numbers that a person of ordinary skill in the art would consider equivalent to the recited value (e.g., having the same function or result). In many instances, the term "about" may include numbers that round to the nearest significant digit.

[0044] Numerical ranges expressed using endpoint notation include all numbers within that range (e.g., 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, and 5).

[0045] As used in this specification and the appended claims, the singular forms "a", "an", and "the" include plural referents unless the context clearly dictates otherwise. As used in this specification and the appended claims, the term "or" is generally used in its inclusive sense (i.e., "and / or") unless the context clearly dictates otherwise.

[0046] As used in this specification and the appended claims, the singular forms "a", "an", and "the" include plural referents unless the context clearly dictates otherwise. As used in this specification and the appended claims, the term "or" is generally used in its inclusive sense (i.e., "and / or") unless the context clearly dictates otherwise. Note that for ease of understanding, some features of the present disclosure may be described in the singular, even though these features may be plural or repeated in the disclosed embodiments. Each instance of a feature may include and / or be encompassed by a single disclosure unless there is an express contrary statement. For purposes of simplicity and clarity, not all elements of the present disclosure must be shown in each figure or discussed in detail below. However, it should be understood that the following discussion may apply equally to any and / or all components having more than one part, unless there is an express contrary statement. Additionally, for clarity, not all instances of some elements or features are shown in each figure.

[0047] Relative terms, such as "proximal", "distal", "advance", "retract", and variations thereof, etc., can generally be considered with respect to the positioning, orientation, and / or operation of various components relative to the user / operator / handler of the device, where "proximal" and "retract" indicate or refer to closer to or toward the user, while "distal" and "advance" indicate or refer to farther from or away from the user. In some cases, the terms "proximal" and "distal" can be arbitrarily assigned for ease of understanding the present disclosure, and such cases will be apparent to those skilled in the art. Other related terms, such as "upstream", "downstream", "inflow", and "outflow", refer to the direction of fluid flow within a lumen (such as a body cavity, blood vessel, or within the device). Still other related terms, such as "axial", "circumferential", "longitudinal", "lateral", "radial", etc. and / or variations thereof generally refer to the direction and / or orientation relative to the central longitudinal axis of the disclosed structure or device.

[0048] The term "extent" can be understood as the maximum measurement of the stated or identified dimension, unless the extent or dimension is preceded by "minimum" or identified as "minimum", in which case it can be understood as the minimum dimension of the stated or identified dimension. For example, an "outer extent" can be understood as the outer dimension, a "radial extent" can be understood as the radial dimension, a "longitudinal extent" can be understood as the longitudinal dimension, etc. Each instance of "extent" can be different (e.g., axial, longitudinal, lateral, radial, circumferential, etc.) and will be apparent to those skilled in the art from the respective context of use. Generally, an "extent" can be considered the maximum possible dimension measured according to the intended use, while a "minimum extent" can be considered the minimum possible dimension measured according to the intended use. In some cases, an "extent" can typically be measured orthogonally within a plane and / or cross-section, but it will be apparent from a particular context that it can be measured in different ways, such as but not limited to angularly, radially, circumferentially (e.g., along an arc), etc.

[0049] The terms "integral" and "unitary" generally refer to one or more elements made or composed of a single structure or underlying unit / element. Integral and / or unitary elements should exclude structures and / or features made by assembling or otherwise joining multiple discrete elements together.

[0050] Note that references in the specification to "an embodiment", "some embodiments", "other embodiments", etc., mean that the described embodiments may include a particular feature, structure, or characteristic, but not every embodiment must include that particular feature, structure, or characteristic. Moreover, these phrases do not necessarily refer to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, the use of that particular feature, structure, or characteristic in connection with other embodiments, whether or not explicitly described, is within the knowledge of those skilled in the art, unless the contrary is explicitly stated. That is, as will be understood by those of ordinary skill in the art, even if not explicitly shown in a particular combination, the various individual elements described below are still considered combinable or arrangeable with each other to form other additional embodiments or to supplement and / or enrich the described embodiments.

[0051] For clarity, certain identified numerical designations (e.g., first, second, third, fourth, etc.) may be used in the specification and / or claims to name and / or distinguish various described and / or claimed features. It should be understood that the numerical terms are not restrictive but merely exemplary. In some embodiments, for the sake of brevity and clarity, changes and departures may be made from the previously used numerical designations. That is, a feature identified as a "first" element may later be referred to as a "second" element, a "third" element, etc., and / or different features may be referred to as a "first" element. The meaning and / or name in each case will be apparent to a skilled practitioner.

[0052] The following figures illustrate selected components and / or arrangements of an implant for closing a left atrial appendage, a system for closing a left atrial appendage, and / or a method of using the implant and / or system. It should be noted that in any given figure, for simplicity, some features may not be shown or may be shown schematically. Other details regarding some components of the implant and / or system may be shown in more detail in other figures. Although discussed in the context of closing a left atrial appendage, the implant and / or system may also be used in other interventional and / or percutaneous medical procedures within a patient's body. Similarly, the devices and methods described herein regarding percutaneous deployment may be suitably used in other types of surgical procedures. For example, in some examples, the device may be used in non-percutaneous procedures. The devices and methods according to the present disclosure may also be adapted and configured for other uses within an anatomical structure.

[0053] Figure 1is a partial cross-sectional view of the left atrial appendage 10. In some embodiments, the left atrial appendage (LAA) 10 may have a complex geometry and / or an irregular surface area. It should be understood that the illustrated LAA 10 is merely one of many possible shapes and sizes of the LAA 10, which can vary from patient to patient. Those skilled in the art will also recognize that the medical devices, systems, and / or methods disclosed herein can be adapted to various sizes and shapes of the LAA 10 as needed. The left atrial appendage 10 may include a generally longitudinal axis 12 disposed along the depth of the body 20 of the left atrial appendage 10. The body 20 may include a lateral wall 14 and an orifice 16 that forms a proximal opening 18. In some examples, the lateral extent of the orifice 16 and / or the lateral wall 14 may be less than or fewer than the depth of the body 20 along the longitudinal axis 12, or the depth of the body 20 may be greater than the lateral extent of the orifice 16 and / or the lateral wall 14. In some examples, the LAA 10 may rapidly narrow along the depth of the body 20, or the left atrial appendage may maintain a generally constant lateral extent along most of the depth of the body 20. In some examples, the LAA 10 may include a most distal region that forms or is arranged as a tail-like element associated with the distal portion of the body 20. In some examples, the most distal region may project radially or laterally away from the longitudinal axis 12.

[0054] In some cases, a device known as a LAAC (left atrial appendage closure) device may be implanted within the LAA 10, such as near or within the orifice 16, in order to isolate the interior of the LAA 10 from the remainder of the interior of the heart. Figure 2 and Figure 3 A view of a left atrial appendage closure (LAAC) device 100 is provided. The LAAC device 100 may include an expandable frame 110 that is configured to axially and / or radially transition between a fully constrained configuration and a fully unconstrained configuration along a central longitudinal axis. In the fully constrained configuration, the expandable frame 110 may be axially elongated and / or radially compressed. In the fully unconstrained configuration, the expandable frame 110 may be axially shortened and / or radially expanded.

[0055] As Figure 3 shown, the figure illustrates selected features of the LAAC device 100 in a fully unconstrained configuration, and the expandable frame 110 may have a plurality of struts disposed about a central longitudinal axis. In some embodiments, the plurality of struts may define a plurality of cells. In some embodiments, the plurality of cells may be a plurality of closed cells. In some embodiments, the plurality of cells may be a plurality of open cells. In some embodiments, the plurality of cells may include a plurality of open cells and a plurality of closed cells in various combinations and / or arrangements.

[0056] The expandable frame 110 may include a proximal hub 112 and a distal hub 114. In some embodiments, the proximal hub 112 and / or the distal hub 114 may be centered about and / or coaxial with a longitudinal axis. A plurality of struts may be joined together and / or fixedly attached to the proximal hub 112 and / or the distal hub 114 at the proximal hub 112 and / or the distal hub 114. The proximal hub 112 may be configured to releasably connect, secure, and / or attach the LAAC device 100 and / or the expandable frame 110 to a delivery device. In some embodiments, the proximal hub 112 may include internal threads configured to rotatably and / or threadedly engage an externally threaded distal end of the delivery device. Other configurations for releasably securing the left atrial appendage occlusion device 100 to the delivery device are also contemplated. As described herein, for clarity, some features are not shown in every figure.

[0057] The expandable frame 110 and / or the plurality of struts may be formed from and / or cut from tubular members. In some embodiments, the expandable frame 110 and / or the plurality of struts may be integrally formed from and / or cut from a single piece. In some embodiments, the expandable frame 110 and / or the plurality of struts may be integrally formed from and / or cut from a single tubular member and subsequently formed and / or heat-set into a desired shape of a completely unconstrained configuration. In some embodiments, the expandable frame 110 and / or the plurality of struts may be integrally formed from and / or cut from a single flat member or sheet and then rolled or formed into a tubular structure and subsequently formed and / or heat-set into a desired shape of a completely unconstrained configuration. Some exemplary ways and / or methods of fabricating and / or forming the expandable frame 110 and / or the plurality of struts include laser cutting, machining, stamping, molding, electrical discharge machining (EDM), chemical dissolution, and the like. Other ways and / or methods are also contemplated.

[0058] In some embodiments, the expandable frame 110 can include at least one anchoring member 116 that extends radially outward from the expandable frame in a completely unconstrained configuration. In some embodiments, the expandable frame 110 can include at least one anchoring member 116 that extends radially outward from the expandable frame 110. In some embodiments, the expandable frame 110 can include at least one anchoring member 116 that extends radially outward from the expandable frame 110 near the proximal shoulder of the expandable frame 110. In some embodiments, the expandable frame 110 can include at least one anchoring member 116 that extends radially outward from the expandable frame 110 near the intermediate section of the expandable frame 110. In some embodiments, at least one anchoring member 116 can be configured to engage the lateral wall of the body of the left atrial appendage. In some embodiments, at least one anchoring member 116 can be formed as a J-shaped hook having a free end that extends in a proximal direction and / or toward a proximal direction relative to the central longitudinal axis of the left atrial appendage occluder device 100 and / or the expandable frame 110. Other configurations are also contemplated.

[0059] In some embodiments, the LAAC device 100 can optionally include a closure element 120 that is connected to at least a portion of the expandable frame 110 and / or the plurality of struts, disposed on at least a portion of the expandable frame and / or the plurality of struts, disposed above at least a portion of the expandable frame and / or the plurality of struts, disposed around at least a portion of the expandable frame and / or the plurality of struts, and / or disposed radially external to at least a portion of the expandable frame and / or the plurality of struts, as Figure 4 shown. In some embodiments, the closure element 120 can be attached to the proximal hub 112 and / or can be attached to the expandable frame at the proximal hub 112. In some embodiments, the closure element 120 can extend radially outward from the proximal hub 112 and / or can extend distally from the proximal hub. In some embodiments, the closure element 120 can be attached and / or secured to the expandable frame 110 at a plurality of discrete locations. In some embodiments, one, some, and / or all of the at least one anchoring member 116 can extend through the closure element 120 (if present).

[0060] In some embodiments, the closure element 120 can include a membrane, fabric, mesh, tissue element, or other suitable configuration. In some embodiments, the closure element 120 can be porous. In some embodiments, the closure element 120 can be non-porous. In some embodiments, the closure element 120 can be permeable to selected gases and / or fluids. In some embodiments, the closure element 120 can be substantially impermeable to selected gases and / or fluids, such as blood, water, etc. In some embodiments, the closure element 120 can be designed, sized, and / or configured to prevent thrombus and / or embolization material from flowing out of the LAA 10 into the left atrium and / or the patient's bloodstream. In some embodiments, the closure element 120 can be configured to promote endothelialization after implantation, thereby effectively removing the target site (e.g., left atrial appendage, etc.) from the patient's circulatory system. Some suitable but non-limiting examples of materials for the closure element 120 are discussed below.

[0061] As will be understood by those skilled in the art, anatomical features can vary in size and / or shape. In some embodiments, the LAA can have an irregular (e.g., elongated and / or oblong) cross-sectional shape. In some embodiments, when deployed and / or expanded within the LAA 10, the expandable frame 110 can be compliant and substantially conform to and / or sealingly engage the shape and / or geometry of the lateral walls of the LAA. In some embodiments, the LAAC device 100 can expand to a size, extent, or shape that is less than or different from a completely unconstrained configuration, which is determined by the surrounding tissue and / or the lateral walls of the left atrial appendage. In some embodiments, the expandable frame 110 can be configured to shape and / or stretch the tissue of the LAA such that the lateral walls of the LAA 10 substantially conform to the outer shape of the expandable frame 110. Other configurations are also contemplated.

[0062] In some cases, the LAAC device 100 can be adapted to assist in sealing the irregularly shaped orifice 16 around the LAA 10. In some cases, as Figure 2 and Figure 3As shown, the LAAC device 100 can be considered to have an overall circular shape. The circular shape may not fit well against the orifice, such as the orifice 16 is not circular but elliptical in shape, or may have an irregular boundary around at least a portion of the orifice. The following figures provide exemplary but non-limiting examples of LAAC devices that include one or more expandable elements that are capable of expanding and assisting in sealing against the orifice. In some cases, one or more expandable elements may be adapted to absorb or trap blood for expansion. In some cases, one or more expandable elements may include one or more coagulants, such as but not limited to fibrinogen, such that when one or more expandable elements trap blood within the one or more expandable elements, the blood coagulates, thereby assisting in expanding the one or more expandable elements into contact with the irregular orifice and remaining in the expanded configuration. It should be understood that the expansion of the one or more expandable elements is different from the expansion of the expandable frame 110 from the contracted configuration for delivery to the expanded configuration for deployment.

[0063] Figure 4 is a schematic view of an exemplary LAAC device 200 that includes an expandable frame 210. The LAAC device 200 can be considered similar to the LAAC device 100, but includes expandable elements 220. The expandable elements 220 extend around the outer periphery 222 of the expandable frame 210. Since Figure 4 is a schematic cross-sectional view, the expandable element 220 is shown as a single element near the top of the LAAC device 200 (in the illustrated orientation) and as a single element near the bottom of the LAAC device 200. It should be understood that the expandable element 220 extends continuously around the outer periphery 222 of the expandable frame 210. For example, the outer periphery 222 can be considered to extend around the circumference of the expandable frame 210.

[0064] The expandable element 220 can be considered to be formed of a fabric or polymer sheet or laminate and is adapted to allow blood to flow into the interior of the expandable element 220. In some cases, the expandable element 220 may be open at the proximal end 224 of the LAAC device 200 to trap blood flowing into the LAA 10 in the direction shown by the arrow 226. In some cases, the expandable element 220 may be open at the distal end 228 of the LAAC device 200 to trap blood flowing out of the LAA 10 in the direction shown by the arrow 230. In some cases, the expandable element 220 may be porous to blood, thereby allowing blood moving in either direction to enter the interior of the expandable element 220.

[0065] The expandable element 220 may include a coagulant disposed within the expandable element 220, such as but not limited to fibrinogen, such that blood flowing into the interior of the expandable element 220 will cause coagulation. In some cases, the expandable element 220 may be filled with a material that swells in response to contact with water. For example, the expandable element 220 may be filled with a hydrogel. Since water is a major component of blood, the expandable element 220 will swell after deployment, thereby assisting in the sealing between the LAAC device 200 and the irregular orifice. In some cases, the expandable element 220 may include a shape memory foam that will expand once the LAAC device 200 is implanted.

[0066] Figure 5 is an enlarged schematic view of a double - layer bag filter 300 that can be used to form an expandable element. Figure 6 and Figure 7 provides illustrative but non - limiting examples of expandable elements that can be formed using multiple bag filters 300. In some cases, the double - layer bag filter 300 may include an inner layer 310 and an outer layer 320. The inner layer 310 and the outer layer 320 may be fixedly attached to each other at intervals by stitching 330 to form a tapered structure as shown. In some cases, the bag filter 300 may be formed by forming a tapered shape from a suitable material and then adhesively attaching adjacent tapered shapes together or perhaps by stitching adjacent tapered shapes together.

[0067] The inner layer 310 and the outer layer 320 may be formed of any suitable material, including blood - permeable materials. In some cases, the inner layer 310 and the outer layer 320 are formed of non - blood - permeable materials. Examples of suitable materials for the inner layer 310 and the outer layer 320 include textiles or sheets or permeable sheets of PET (polyethylene terephthalate), polyester, polyurethane, and fluoropolymers (such as ePTFE (expanded polytetrafluoroethylene)). In some cases, the bag filter 300 may include a coagulant coated on the interior of the bag filter 300. In some cases, the bag filter 300 may be substantially filled with a coagulant or at least partially filled with a coagulant.

[0068] As described above, the bag filters 300 may be joined together to form an expandable element that can subsequently be fixedly attached relative to a LAAC device (such as LAAC device 100) to form a LAAC device that seals better against an irregular orifice. Figure 6 is a schematic view of an expandable element 400 incorporating multiple bag filters 300. As Figure 5As shown, the expandable element 400 can be formed by periodically stitching an inner layer (such as inner layer 310) and an outer layer (such as outer layer 320) together. The dashed line 410 can be considered to represent the outer periphery of the LAAC device to which the expandable element 400 can be secured. Since the expandable element 400 is wider than the outer periphery of the LAAC device represented by the dashed line 410, it should be understood that the expandable element 400 can be folded down over the outer periphery of the LAAC device and can thus be positioned to seal between the LAAC device and the irregular orifice.

[0069] Figure 7 is a schematic view of an expandable element 500 that can subsequently be secured relative to a LAAC device (such as LAAC device 100) to form a LAAC device that better seals an irregular orifice. The expandable element 500 can be considered to include a first expandable element 510 and a second expandable element 520 disposed directly on the first expandable element 510. Each of the first expandable element 510 and the second expandable element 520 can be considered equivalent to Figure 6 the expandable element 400 shown. Adding the second expandable element can provide additional sealing around the outer periphery of the LAAC device represented by the dashed line 410. In some cases, the second expandable element 520 can be arranged such that the widened open portions of each filter bag within the second expandable element 520 mate between the widened open portions of each filter bag within the first expandable element 510.

[0070] Figure 8 is a schematic view of an exemplary LAAC device 600 that includes an expandable framework 610. The expandable framework 610 can be considered to be similar (if not identical) to the expandable framework 110 described with respect to Figure 2 and can include a covering (such as covering 120) or not include a covering. The LAAC device 600 includes an expandable element 620 that extends around the outer periphery 630 of the LAAC device 600. It can be seen that the expandable element 620 includes a plurality of bag filters 300, some of the bag filters 300 being positioned with their open ends facing proximally to capture blood flowing in the direction shown by arrow 640 towards the LAA 10 or blood flowing into the LAA, and some of the bag filters 300 being positioned with their open ends facing distally to capture blood flowing away from the LAA 10 in the direction shown by arrow 650 or blood flowing out of the LAA. In some cases, a single bag filter 300 can have a closed end. In some cases, a single bag filter 300 can have two open ends, but can include a one-way valve that allows blood to flow in a first direction but not in the opposite direction.

[0071] Figure 9FIG. 0 is a schematic view of an exemplary LAAC device 700 including an expandable frame 710. The expandable frame 710 may be considered similar (if not identical) to the expandable frame 110 described with respect to Figure 2 and may include a covering (such as covering 120) or may not include a covering. The LAAC device 700 includes a corrugated three-layer expandable element 720. As Figure 10 shown, the corrugated three-layer expandable element 720 may be adapted to expand to conform to and seal against an irregular orifice 716. The corrugated three-layer expandable element 720 includes an inner layer 730 that mates with the outer surface of the expandable frame 710, an outer layer 740 adapted to seal against the irregular orifice 716, and an intermediate layer 750 that alternates between being attached to or adjacent to the inner layer 730 and being attached to or adjacent to the outer layer 740. In some cases, the intermediate layer 750 may be similar to the inner layer 730 and the outer layer 740. As an example, the configuration of the intermediate layer 750 may be similar to the Figure 7 alternating pockets shown. In some cases, the expandable material may be secured to the intermediate layer 750 or may not be secured to the intermediate layer. The expandable material may be secured only to the inner layer 730, only to the outer layer 740, or in some cases may be secured to the inner layer 730, the outer layer 740, and the intermediate layer 750.

[0072] Figure 10 FIG. 10 shows the LAAC device 700 disposed within the irregular orifice 716. It can be seen that the corrugated three-layer expandable element 720 has expanded or inflated to fill the space and thereby seal against the irregular orifice 716. In some cases, the space between the inner layer 730 and the outer layer 740 is filled with blood. In some cases, the space between the inner layer 730 and the outer layer 740 may include a coagulant that causes the blood entering the space to coagulate. In some cases, at least the outer layer 740 may be formed of a blood-permeable material to allow blood to enter the space between the inner layer 730 and the outer layer 740. Examples of suitable materials include textiles or sheets or permeable sheets of PET (polyethylene terephthalate), polyester, polyurethane, and fluoropolymers (such as ePTFE (expanded polytetrafluoroethylene)).

[0073] Figure 11800 is a schematic diagram of an exemplary valved mesh 800 that can be used as an expandable element with a LAAC device. As shown, the valved mesh 800 includes a first component 810 shown as being disposed in an XY plane and a second component 820 shown as being disposed in a YZ plane. It should be understood that this is merely illustrative, as the valved mesh 800 may not be precisely arranged in an XYZ coordinate system in which the components are arranged at right angles, but other angles may be adopted between the components. Each of the first component 810 and the second component 820 can be considered to include a plurality of one-way valves 830 that control which direction(s) blood can flow through the valved mesh 800 and which direction(s) blood is not allowed to flow through the valved mesh 800. In some cases, the valved mesh 800 may include a coagulant that causes blood entering the inside of the valved mesh 800 to coagulate, thereby causing the valved mesh 800 to expand.

[0074] It should be appreciated that in some cases, a covering that spans the expandable framework 110, such as the closure element 120, may have to accommodate changes in the size of the expandable framework 110. In other words, the covering must be able to stretch. Figure 12A , Figure 12B and Figure 12C Details of a cover 900 that can be used with the LAAC devices described herein are provided together. Cover 900 includes a webbing 910 made of relatively thick fibers. Webbing 920 spans the distance between the relatively thick fibers that form webbing 910 and is formed of relatively thin fibers. In some cases, webbing 910 can be formed of fibers having an average diameter in the range of 5 μm to 10 μm, and webbing 920 can be formed of fibers having an average diameter in the range of 25 μm to 100 μm. In some cases, webbing 910 is arranged in a honeycomb manner, but this is not required in all cases.

[0075] In some cases, webbing 910 may be formed from fibers having a relatively large proportion of elastomer and a relatively small proportion of a second polymer, such as, but not limited to, PET (polyethylene terephthalate). In some cases, webbing 910 may be formed from fibers that are at least 50% elastomer, and webbing 920 may be formed from fibers that are at least 50% PET. In some cases, webbing 910 may be formed from fibers that include approximately 70% elastomer and approximately 30% PET. In some cases, webbing 920 may be formed from fibers that have a relatively large proportion of PET and a relatively small proportion of elastomer. In some cases, webbing 920 may be formed from fibers that include approximately 30% PET and approximately 70% elastomer. The elastomers used for webbing 910 and webbing 920 may include one or more fluoroelastomers, polyurethane elastomers, Thermoplastic elastomer, copolyester elastomer, hydrophilic elastomer, polyamide 11 or polyether segment.

[0076] Figure 12B and Figure 12C collectively show how the covering 900 responds to an applied force. In particular, Figure 12B and Figure 12C collectively show that tension applied in any direction (as shown by arrows 930, 940, 950, and 960) results in equal porosity. In Figure 12C it can be seen that the mesh 970 has equal pore sizes. In some cases, the covering 900 can be considered to exhibit auxetic properties. In some cases, the covering 900 can include materials such as urethane or nylon. In some cases, the covering 900 can also include radiopaque elements. In some cases, the covering 900 can be a fabric matrix formed in an auxetic pattern such that the stretch and compliance are balanced along the planar radial axis and are uniformly distributed in terms of porosity for hemodynamic flow and hemostasis.

[0077] The devices and their various components described herein can be manufactured according to substantially any suitable manufacturing technique, including molding, casting, machining, etc., or any other suitable technique. Additionally, the various structures can include materials commonly associated with medical devices, such as metals, metal alloys, polymers, metal-polymer composites, ceramics, combinations thereof, etc., or any other suitable materials. These materials can include transparent or translucent materials to aid visualization during the surgical procedure. Some examples of suitable metals and metal alloys include stainless steels such as 304V, 304L, and 316LV stainless steels; low carbon steel; nickel-titanium alloys such as linear elastic and / or superelastic nitinol; other nickel alloys such as nickel-chromium-molybdenum alloys (e.g., UNS: N06625, such as 625, UNS; N06022, such as UNS: N10276, such as other alloys, etc.), nickel-copper alloys (e.g., UNS: N04400, such as 400, 400, 400, etc.), nickel-cobalt-chromium-molybdenum alloys (e.g., UNS: R30035, such as etc.), nickel-molybdenum alloys (e.g., UNS: N10665, such as ), other nickel-chromium alloys, other nickel-molybdenum alloys, other nickel-cobalt alloys, other nickel-iron alloys, other nickel-copper alloys, other nickel-tungsten or tungsten alloys, etc.; cobalt-chromium alloys; cobalt-chromium-molybdenum alloys (e.g., UNS: R30003, such as etc.); platinum-rich stainless steel; combinations thereof; or any other suitable material.

[0078] Some examples of suitable polymers can include polytetrafluoroethylene (PTFE), ethylene tetrafluoroethylene (ETFE), fluorinated ethylene propylene (FEP), polyoxymethylene (POM, e.g., available from DuPont ), polyether block ester, polyurethane, polypropylene (PP), polyvinyl chloride (PVC), polyether ester (e.g., available from DSM Engineering Plastics ), ether-based or ester-based copolymers (e.g., butene / poly(alkylene ether) phthalate and / or other polyester elastomers, such as available from DuPont ), polyamide (e.g., available from Bayer or available from Elf Atochem ), elastic polyamide, block polyamide / ether, polyether block amide (PEBA, e.g., available under the trade name ), ethylene vinyl acetate copolymer (EVA), silicone resin, polyethylene (PE), high-density polyethylene, low-density polyethylene, linear low-density polyethylene (e.g., ), polyester, polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polypropylene terephthalate, polyethylene naphthalate (PEN), polyether ether ketone (PEEK), polyimide (PI), polyetherimide (PEI), polyphenylene sulfide (PPS), polyphenylene oxide (PPO), poly(p-phenylene terephthalamide) (e.g., ), polysulfone, nylon, nylon-12, (e.g., available from EMS American Grilon ), perfluoro(propyl vinyl ether) (PFA), ethylene vinyl alcohol, polyolefin, polystyrene, epoxy resin, polyvinylidene chloride (PVdC), polycarbonate, ionomer, biocompatible polymer, other suitable materials, or mixtures, compositions, copolymers, polymer / metal composites, etc.

[0079] In some embodiments, the systems and / or other elements disclosed herein can include a fabric material disposed on or within a structure. The fabric material can be composed of a biocompatible material (such as a polymeric material or a biomaterial) suitable for promoting tissue ingrowth. In some embodiments, the fabric material can include a bioabsorbable material. Some examples of suitable fabric materials include, but are not limited to, polyethylene glycol (PEG), nylon, polytetrafluoroethylene (PTFE, ePTFE), polyolefin materials (such as polyethylene, polypropylene, polyester, polyurethane, and / or blends or combinations thereof).

[0080] In some embodiments, the systems and / or other elements disclosed herein may comprise and / or be formed from textile materials. Some examples of suitable textile materials may include synthetic yarns, which may be flat, shaped, twisted, textured, pre-shrunk or unshrunk. Synthetic biocompatible yarns suitable for the present disclosure include, but are not limited to, polyesters, including polyethylene terephthalate (PET) polyester, polypropylene, polyethylene, polyurethane, polyolefins, polyvinyl alcohol, polymethyl acetate, polyamides, naphthalene dicarboxylic derivatives, natural silk, and polytetrafluoroethylene. Additionally, at least one synthetic yarn may be a metal yarn or a glass or ceramic yarn or fiber. Useful metal yarns include those made of or containing stainless steel, platinum, gold, titanium, tantalum, or nickel-cobalt-chromium-based alloys. The yarn may further include carbon fibers, glass, or ceramic fibers. Desirably, the yarn is made of a thermoplastic material, including but not limited to polyester, polypropylene, polyethylene, polyurethane, polynaphthalene, polytetrafluoroethylene, etc. The yarn may be of the multifilament type, monofilament type, or staple type. The type and denier of the selected yarn may be chosen in a manner to form a biocompatible and implantable prosthesis (and more specifically, to form a vascular structure having the desired properties).

[0081] In some embodiments, the systems and / or other elements disclosed herein may include a suitable therapeutic agent and / or be treated with a suitable therapeutic agent. Some examples of suitable therapeutic agents may include antithrombotic agents (such as heparin, heparin derivatives, urokinase, and PPack (D-phenylalanine proline arginine chloromethyl ketone)); antiproliferative agents (such as enoxaparin, angiotensin, monoclonal antibodies capable of blocking smooth muscle cell proliferation, hirudin, and acetylsalicylic acid); anti-inflammatory agents (such as dexamethasone, prednisolone, corticosterone, budesonide, estrogen, sulfasalazine, and mesalazine); antitumor / antiproliferative / antimitotic agents (such as paclitaxel, 5-fluorouracil, cisplatin, vinblastine, vincristine, epothilone, endostatin, angiostatin, and thymidine kinase inhibitors); anesthetics (such as lidocaine, bupivacaine, and ropivacaine); anticoagulants (such as D-Phe-Pro-Arg chloromethyl ketone, RGD peptide-containing compounds, heparin, antithrombin compounds, platelet receptor antagonists, antithrombin antibodies, antiplatelet receptor antibodies, aspirin, prostaglandin inhibitors, platelet inhibitors, and tick antiplatelet peptides); vascular cell growth promoters (such as growth factor inhibitors, growth factor receptor antagonists, transcriptional activators, and translational promoters); vascular cell growth inhibitors (such as growth factor inhibitors, growth factor receptor antagonists, transcriptional repressors, translational repressors, replication inhibitors, inhibitory antibodies, antibodies against growth factors, bifunctional molecules composed of growth factors and cytotoxins, bifunctional molecules composed of antibodies and cytotoxins); cholesterol-lowering agents; vasodilators; and agents that interfere with endogenous vasoactive mechanisms.

[0082] It should be understood that the present disclosure is merely exemplary in many respects. Changes may be made in details, particularly in the arrangement of shapes, sizes, and steps, without departing from the scope of the present disclosure. To the appropriate extent, this may include using any features of one exemplary embodiment in other embodiments. Of course, the scope of the invention is defined by the language of the appended claims.

Claims

1. An implantable medical device, which comprises: an expandable frame that can expand between a contracted configuration for delivery and an expanded configuration for deployment, the expandable frame including a periphery defined by the expandable frame; a covering that spans at least a portion of the expandable frame; and an expandable element fixedly attached relative to the periphery, the expandable element being adapted to seal against an irregular body opening.

2. The implantable medical device according to claim 1, wherein, the irregular body opening includes an orifice of the patient's LAA (left atrial appendage).

3. The implantable medical device according to any one of claims 1 or 2, wherein, the expandable element includes a plurality of bag filters arranged around the periphery.

4. The implantable medical device according to claim 3, wherein, each of the plurality of bag filters has an open end and a closed end, and each of the plurality of bag filters is arranged around the periphery such that the open end faces one direction and the closed end faces the opposite direction.

5. The implantable medical device according to claim 3, wherein, each of the plurality of bag filters has an open end and a closed end, and each of the plurality of bag filters is arranged around the periphery in an alternating manner, wherein the open ends of the bag filters are arranged close to the closed ends of adjacent bag filters.

6. The implantable medical device according to claim 3, wherein, at least some of the plurality of bag filters have two open ends with one-way valves that restrict blood flow therethrough.

7. The implantable medical device according to claim 3, wherein, at least some of the plurality of bag filters include a coagulant disposed within the bag filter.

8. The implantable medical device according to any one of claims 1 or 2, wherein, the expandable element includes a corrugated three-layer element extending around the periphery, the corrugated three-layer element including an inner layer, an outer layer, and intermediate middle layers alternating between being attached to the inner layer and being attached to the outer layer.

9. The implantable medical device according to claim 8, wherein, the corrugated three-layer element includes a coagulant.

10. The implantable medical device according to any one of claims 1 or 2, wherein, the expandable element includes an all-round valved mesh.

11. The implantable medical device according to any one of claims 1 to 10, wherein, the implantable medical device includes a LAAC (left atrial appendage closure) device.

12. A LAAC (left atrial appendage closure) device adapted to fit within an irregular orifice of a patient's LAA (left atrial appendage), the LAAC device comprises: an expandable frame that can expand between a contracted configuration for delivery and an expanded configuration for deployment, the expandable frame including a periphery defined by the expandable frame; a covering that spans at least a portion of the expandable frame; and An expandable element adapted to seal against an irregular orifice of a patient's LAA.

13. The LAAC device according to claim 12, wherein, the expandable element includes a coagulant.

14. The LAAC device according to claim 12, wherein, the expandable element includes an inflatable member.

15. The LAAC device according to claim 12, wherein, the expandable element includes a plurality of bag filters.

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