Patent Description:
The present disclosure relates generally to medical devices that are used in the human body. In particular, the present disclosure is directed to embodiments of an occlusion device that enables removal of a device frame from the occlusion device after the occlusion device is deployed in the human body. More specifically, the present disclosure is directed to an occlusion device with a temporary device frame that promotes native tissue growth while maintaining the fundamental function and effectiveness of an occluder. The embodiments disclosed herein enable the removal of the device frame and the promotion of native tissue growth by the incorporation of a biomaterial cover over at least a portion of the device frame.

An occluder is a medical device used to treat (e.g., occlude) tissue at a target site within the human body, such as an abnormality, a vessel, an organ, an opening, a chamber, a channel, a hole, a cavity, a lumen, or the like. For example, an occluder may be used in transcatheter secundum atrial septal defect closures. Secundum atrial septal defects are common congenital heart defects that allow blood to flow between the left and right atria of the heart, decreasing cardiac output. Occluders may be employed to block this blood flow.

At least some known occluders may be formed from shape-formed braided nitinol that is permanently implanted in the target site of the human body. Accordingly, the presence of the occluder creates a permanent foreign object within the patient. The presence of a foreign object can present adverse side effects, such as erosion of tissue around the implanted device, development of arrhythmia, and, where a patient may develop a nickel allergy, adverse allergic effects.

Accordingly, it would be desirable to reduce the presence of a permanent foreign object within the body of the patient as much as possible, while maintaining the fundamental function and effectiveness of an occluder.

The present disclosure concerns a medical device comprising the features defined in the independent claim <NUM> and a retrieval system comprising the features defined in the claim <NUM>.

Corresponding reference characters indicate corresponding parts throughout the several views of the drawings. It is understood that that Figures are not necessarily to scale.

The present disclosure relates generally to medical devices that are used in the human body. Specifically, the present disclosure provides medical devices including occlusion devices having a biomaterial cover and a frame that is removable from the biomaterial cover, and from the patient's body, after the occlusion device has been deployed within the body at a target site. The biomaterial cover promotes tissue ingrowth such that, after a period of time, the biomaterial cover and tissue provide sufficient occlusion of the target site. Thereafter, the frame can be withdrawn from the at least one biomaterial cover without detriment to the occlusive effects of the occlusion device. In one exemplary embodiment, the frame includes a plurality of prongs, which enables de-coupling of the frame from the biomaterial cover as described herein.

Accordingly, the occlusion devices of the present disclosure promote native tissue growth to achieve the fundamental function and effectiveness of the occluder, which enables the removal of the frame from the human body, to reduce or eliminate the above-described adverse effects of foreign objects within the patient's body.

The disclosed embodiments may lead to more consistent and improved patient outcomes. It is contemplated, however, that the described features and methods of the present disclosure as described herein may be incorporated into any number of systems as would be appreciated by one of ordinary skill in the art based on the disclosure herein.

It is understood that the use of the term "target site" is not meant to be limiting, as the medical device may be configured to treat any target site, such as an abnormality, a vessel, an organ, an opening, a chamber, a channel, a hole, a cavity, or the like, located anywhere in the body. The term "vascular abnormality," as used herein is not meant to be limiting, as the medical device may be configured to bridge or otherwise support a variety of vascular abnormalities. For example, the vascular abnormality could be any abnormality that affects the shape of the native lumen, such as an atrial septal defect, an LAA, a lesion, a vessel dissection, or a tumor. Embodiments of the medical device may be useful, for example, for occluding an LAA, ASD, VSD, or PDA, as noted above. Furthermore, the term "lumen" is also not meant to be limiting, as the vascular abnormality may reside in a variety of locations within the vasculature, such as a vessel, an artery, a vein, a passageway, an organ, a cavity, or the like. For ease of explanation, the examples used herein refer to the occlusion of a septal defect (e.g., an atrial septal defect or ASD).

As used herein, the term "proximal" refers to a part of the medical device or the delivery device that is closest to the operator, and the term "distal" refers to a part of the medical device or the delivery device that is farther from the operator at any given time as the medical device is being delivered through the delivery device. In addition, the terms "deployed" and "implanted" may be used interchangeably herein.

Some embodiments of the present disclosure provide an improved percutaneous catheter directed intravascular occlusion device for use in the vasculature in patients' bodies, such as blood vessels, channels, lumens, a hole through tissue, cavities, and the like, such as an atrial septal defect. Other physiologic conditions in the body occur where it is also desirous to occlude a vessel or other passageway to prevent blood flow into or therethrough. These device embodiments may be used anywhere in the vasculature where the anatomical conditions are appropriate for the design.

The medical device may include one or more discs that are at least partially covered by a biomaterial cover that acts as an occlusive material, while promoting native issue growth, which is configured to occlude or substantially preclude the flow of blood. Most commonly, blood flow may be occluded immediately. However, it is contemplated that, in some cases, some blood flow may occur. Accordingly, as used herein, "substantially preclude" or, likewise, "substantially occluded blood flow" shall mean, functionally, that minimal or trace blood flow around or through the medical device may occur for a short time, but that the body's tissue growth onto the biomaterial cover results in full occlusion after this initial time period.

The present disclosure now will be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all embodiments of the disclosure are shown. Indeed, this disclosure may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements.

In at least some conventional or known medical devices used for the occlusion of abnormalities, such as a medical device <NUM> shown in <FIG>, a metal frame <NUM> provides the occlusive property. The occlusive properties of these known devices arise from the facilitation of thrombosis. Metal frame <NUM> is formed from shape-memory material, most commonly Nitinol, that uses a single-layer, seventy-two wire braid design. As described above, when these medical devices are utilized to occlude blood flow through an abnormality, metal frame <NUM> becomes a permanent foreign object within the patient's body. The presence of metal frame <NUM> within the patient's body can potentially lead to adverse side effects such as erosion or development of a nickel allergy.

The medical devices of the present disclosure, which includes a biomaterial cover and a removable frame, minimize these disadvantages of known medical devices.

Turning now to <FIG>, a schematic diagram of a delivery system <NUM> is shown. Delivery system <NUM> includes a delivery device <NUM> including a catheter <NUM> and a coupling member <NUM> configured to couple a distal end of a delivery cable <NUM> to a connecting member <NUM> of a medical device <NUM> for facilitating the deployment of medical device <NUM> at a target site. Medical device <NUM> is deployed to treat the target site, and, in the example embodiment, is an occlusion device ("occluder").

<FIG> and <FIG> illustrate a first exemplary embodiment of medical device <NUM>. Specifically, <FIG> is a side sectional view of medical device <NUM>, and <FIG> is a top sectional view of medical device <NUM>. As shown in <FIG> and <FIG>, medical device <NUM> includes a device frame <NUM> and at least one biomaterial cover <NUM>. Device frame <NUM> includes a proximal disc <NUM> and a distal disc <NUM>. Proximal disc <NUM> at least partially defines a proximal end <NUM> of medical device <NUM> and frame <NUM>, and distal disc <NUM> at least partially defines a distal end <NUM> of medical device <NUM> and frame <NUM>.

Proximal and distal discs <NUM>, <NUM> are joined together by a connecting segment <NUM>. In the exemplary embodiment, connecting segment <NUM> is coaxial with proximal and distal discs <NUM>, <NUM>. In other embodiments, connecting segment <NUM> is other than coaxial with (e.g., off-center with respect to) proximal disc <NUM> and/or distal disc <NUM>. In the exemplary embodiment, connecting member <NUM> is coupled to and extends from a proximal end of connecting segment <NUM>. Alternatively, connecting member <NUM> may be coupled to and extend from proximal disc <NUM>.

Moreover, in the exemplary embodiment, frame <NUM> is a unitary component, and proximal disc <NUM>, distal disc <NUM>, and connecting segment <NUM> are integrally formed with one another. Alternatively, proximal disc <NUM>, distal disc <NUM>, and connecting segment <NUM> are separately formed and are coupled together to form frame <NUM>.

As shown in <FIG>, distal disc <NUM> includes a plurality of prongs <NUM> that define distal disc <NUM>. Although not shown in <FIG>, proximal disc <NUM> is substantially the same as distal disc <NUM> - that is, the description of distal disc <NUM> also applies to proximal disc <NUM>.

Each of prongs <NUM> is arcuate in shape and extends radially outwardly in a first direction <NUM> that is defined from connecting segment <NUM> to a free end <NUM> of the corresponding prong <NUM>. For example, in <FIG>, first direction <NUM> is a generally counter-clockwise direction. It should be readily understood that first direction <NUM> may be clockwise in any other embodiment. This shape or configuration of prongs <NUM> is generally referred to as a "bent star" shape or configuration, referring to the overall "star" configuration of the prongs <NUM> within one of discs <NUM>, <NUM> and the bent (e.g., curved or coiled) free ends <NUM> thereof. Each prong <NUM> is substantially similar to each other prong <NUM> in distal disc <NUM>.

It is contemplated that the plurality of prongs <NUM> may be arranged in many different configurations. The configuration is limited only by the ability to retract the prongs from the biomaterial cover <NUM> to de-couple or withdraw the prongs <NUM> from biomaterial cover <NUM> and remove or withdraw frame <NUM> from biomaterial cover <NUM> (and, therefore, remove or withdraw frame <NUM> from medical device <NUM> at the target site), as described further herein.

In one embodiment, device frame <NUM> is formed from a shape-memory material. One particular shape memory material that may be used is Nitinol. Nitinol alloys are highly elastic and are said to be "superelastic," or "pseudoelastic. " This elasticity may allow medical device <NUM> to be resilient and return to a preset, expanded configuration for deployment following passage in a distorted form through delivery catheter <NUM>. Further examples of materials and manufacturing methods for medical devices with shape memory properties are provided in <CIT>.

It is also understood that device frame <NUM> may be formed from various materials other than Nitinol that have elastic properties, such as stainless steel, trade named alloys such as Elgiloy®, or Hastalloy, Phynox®, MP35N, CoCrMo alloys, metal, polymers, or a mixture of metal(s) and polymer(s). Suitable polymers may include PET (Dacron™), polyester, polypropylene, polyethylene, HDPE, Pebax, nylon, polyurethane, silicone, PTFE, polyolefins and ePTFE. Additionally, it is contemplated that the device frame may comprise any material that has the desired elastic properties to ensure that the device may be deployed, function as an occluder, and be recaptured in a manner disclosed within this application.

Biomaterial cover <NUM>, in the exemplary embodiment, covers or surrounds at least a portion of frame <NUM>. For example, biomaterial cover <NUM> at least partially surrounds proximal disc <NUM> and/or distal disc <NUM>. In the exemplary embodiment, biomaterial cover <NUM> defines one or more cavities in which proximal disc <NUM> and/or distal disc <NUM> are positioned. In the embodiment shown in <FIG>, biomaterial cover <NUM> is two separate components, such as a first or proximal cover <NUM> and a second or distal cover <NUM>. Proximal cover <NUM> at least partially surrounds proximal disc <NUM>, and engages with or is coupled to frame <NUM> at least at proximal disc <NUM>. Proximal cover <NUM> includes a first or outer section <NUM> and a second or inner section <NUM> that together define a cavity <NUM> in which proximal disc <NUM> is positioned. First section <NUM> and/or second section <NUM> engages with or is coupled to proximal disc <NUM>. In some embodiments, second section <NUM> may be further removably coupled to and/or engaged with connecting segment <NUM> (e.g., via bioabsorbable sutures).

Distal cover <NUM> at least partially surrounds distal disc <NUM>, and engages with or is coupled to frame <NUM> at least at distal disc <NUM>. Distal cover <NUM> also includes a first section <NUM> and a second section <NUM> that also define a cavity <NUM>. Distal disc <NUM> is positioned within cavity <NUM>. First section <NUM> and/or second section <NUM> is coupled to distal disc <NUM>. In some embodiments, second section <NUM> may be further removably coupled to and/or engaged with connecting segment <NUM> (e.g., via bioabsorbable sutures). It should be readily understood that, in some embodiments, biomaterial cover <NUM> includes only one of proximal cover <NUM> and distal cover <NUM>.

In the exemplary embodiment, each respective first section <NUM> and second section <NUM> are coupled together and to the respective disc <NUM>, <NUM> of frame <NUM> by bioabsorbable sutures <NUM>. As shown in <FIG>, bioabsorbable sutures <NUM> are specifically arranged to create a respective pocket <NUM> around each prong <NUM>, to improve retention of prongs <NUM> within biomaterial cover <NUM>. As shown in <FIG>, these bioabsorbable sutures <NUM> extend through both the first and second section <NUM>, <NUM> (of the respective disc) to form pockets <NUM>. Bioabsorbable sutures <NUM> may also be used to couple respective first and second sections <NUM>, <NUM> together. For example, bioabsorbable sutures <NUM> are sewn around a circumference of first and second sections <NUM>, <NUM>. Alternatively, where first and second sections <NUM>, <NUM> are integrally formed (i.e., proximal cover <NUM> is a unitary component and/or distal cover <NUM> is a unitary component), bioabsorbable sutures <NUM> are not needed to couple respective first and second sections <NUM>, <NUM> together. Although sutures <NUM> are referred to herein as bioabsorbable, it should be understood that, in some embodiments, suture <NUM> may not be bioabsorabable and may be formed from any suitable suture material.

In some alternative embodiments, as shown in <FIG>, biomaterial cover <NUM> may be a single component that substantially covers an entirety of frame <NUM> (e.g., both proximal and distal discs <NUM>, <NUM> and connecting segment <NUM>, but with an opening remaining at a proximal section thereof for subsequent withdrawal of frame <NUM>). In this embodiment, biomaterial cover <NUM> includes a central section <NUM> coupled to and extending between second sections <NUM> of proximal and distal covers <NUM>, <NUM>. Biomaterial cover <NUM> may be a unitary component (e.g., proximal cover <NUM>, distal cover <NUM>, and central section <NUM> may be integrally formed with one another), or proximal cover <NUM>, distal cover <NUM>, and central section <NUM> may be separately formed and then coupled together to form biomaterial cover <NUM>.

In one embodiment, biomaterial cover <NUM> is formed from a bioabsorbable polymer. The bioabsorbable polymer may include, for example, Poly-L-lactic acid (PLLA), Poly(glycolic acid) (PGA), Copolyesters of poly(e-caprolactone) (PCL), Trimethylene carbonate (TMC), Poly(d-diozanone) (PPDO), and combinations of various polymers. Additionally or alternatively, the biomaterial cover is formed from another polymer. The polymer may include, for example, PET (Dacron™), polyester, polypropylene, polyethylene, HDPE, Pebax, nylon, PTFE, polyolefins and ePTFE.

In other embodiments, biomaterial cover <NUM> may be formed from a tissue, such as pericardial tissues. The tissues may be derived from, for example, porcine, bovine, equine, and/or collagen matrices.

<FIG> illustrates another exemplary embodiment of medical device <NUM> including an alternative configuration of the plurality of prongs <NUM>. In this embodiment, each prong <NUM> is arcuate and extends radially outwardly from connecting segment <NUM> in first direction <NUM>, and the prong <NUM> also includes a helical or coiled free end <NUM> that completes at least one <NUM>° rotation to further reduce the risk of free ends <NUM> puncturing biomaterial cover <NUM>. Moreover, biomaterial cover <NUM> further includes a plurality of circular sewn pockets <NUM>. Each coiled free end <NUM> of a prong <NUM> extends about a respective circular pocket <NUM>. The <NUM>° rotation about the respective circular pocket <NUM> may improve retention of the prong <NUM> within biomaterial cover <NUM>, while still allowing for de-coupling and retraction of the prong <NUM> from biomaterial cover <NUM>.

In the exemplary embodiment, to form medical device <NUM>, proximal disc <NUM> and/or distal disc <NUM> is enclosed by a first section <NUM> and a second section <NUM> of biomaterial cover <NUM>. Bioabsorbable sutures <NUM> are then applied through first section(s) <NUM> and second section(s) <NUM> to form pockets <NUM> that secure prongs <NUM> inside biomaterial cover <NUM>.

In operation, as shown in <FIG>, medical device <NUM> is advanced towards the target site within catheter <NUM> of delivery device <NUM>. Proximal and distal discs <NUM>, <NUM> are folded or compressed within catheter <NUM> during delivery. Once the target site has been reached, medical device <NUM> is deployed from catheter <NUM> into the abnormality to be occluded using delivery cable <NUM>, as shown in <FIG>. Specifically, catheter <NUM> is positioned within or adjacent to the target site, and medical device <NUM> is distally advanced until distal disc <NUM> is released from catheter <NUM>. As described elsewhere herein, the shape memory and/or elastic material defining frame <NUM> causes distal disc <NUM> to unfold or expand to its expanded form, on a distal side of the target site. Thereafter, catheter <NUM> is retracted proximally to release connecting segment <NUM> and proximal disc <NUM> from catheter <NUM>. Proximal disc <NUM> unfolds or expands to its expanded form, on a proximal side of the target site.

When the placement of medical device <NUM> has been assessed and confirmed (e.g., by a physician), coupling member <NUM> of delivery device <NUM> is disconnected from connecting member <NUM> of medical device <NUM>. As shown in <FIG>, in some embodiments, connecting member <NUM> includes internal threads <NUM> configured to mate with external threads <NUM> of coupling member <NUM>. In such cases, disconnecting coupling member <NUM> from connecting member <NUM> includes rotating delivery cable <NUM> in a rotational direction opposite to the direction of mated threads <NUM>, <NUM>. Thereafter, medical device <NUM> is considered fully deployed.

According to the present disclosure, medical device <NUM> is designed such that frame <NUM> can be recaptured and withdrawn or removed from medical device <NUM>, after medical device <NUM> has been deployed at the target site. In at least some embodiments, device frame <NUM> cannot be recaptured for some period of time, or until a sufficient amount of endothelialization has occurred around biomaterial cover <NUM>. The amount of time required for sufficient endothelialization to occur may depend on a number of factors, for example, the material used for biomaterial cover <NUM> or the target site at which medical device <NUM> is deployed. A physician may determine the appropriate time for removal of device frame <NUM>. For instance, the physician may determine there is a medical reason for frame <NUM> to be removed (e.g., a need to intervene again in the same area to, for example, implant a mitral valve, conduct cardiac mapping, or implant an LAA occluder), and, after observing the amount of endothelialization that has taken place to confirm tissue ingrowth is sufficient to maintain occlusion of the target site, the physician may remove frame <NUM> at such a time. In at least some embodiments, the removal can occur after at least about <NUM>-<NUM> days after deployment and implantation of medical device <NUM>.

To recapture and remove frame <NUM>, an implanted medical device <NUM> (i.e., a medical device <NUM> that is currently in place at a target site) must be located. In some embodiments, confirmation may be made that a sufficient amount of endothelialization has taken place, specifically, that the amount of tissue ingrowth is sufficient to provide an occlusive effect.

With reference to <FIG> as well as <FIG>, in some embodiments, a recapture or retrieval system <NUM> is employed to recapture and withdraw or remove frame <NUM> from biomaterial cover <NUM> of the implanted medical device <NUM>. In some instances, recapture system <NUM> includes one more elements in common with delivery system <NUM>, such as delivery device <NUM> and/or delivery catheter <NUM>. In other instances, recapture system <NUM> is wholly separate from delivery system <NUM>. Accordingly, reference is made herein to a retrieval device <NUM> and a retrieval catheter (also referred to as a retrieval sheath) <NUM> of recapture system <NUM>, regardless of their similarity with components of delivery system <NUM>.

Recapture system <NUM> includes a recapture cable <NUM> that is advanced to the target site at which medical device <NUM> was previously deployed. Recapture cable <NUM> includes a coupling member <NUM> at the distal end thereof. Coupling member <NUM> is coupled to proximal end <NUM> of frame <NUM> (e.g., to connecting member <NUM>). To retract prongs <NUM> from biomaterial cover <NUM>, in some exemplary embodiments, frame <NUM> is rotated in a second direction <NUM> (see <FIG>) opposite to first direction <NUM>. This rotation, in second direction <NUM>, causes prongs <NUM> of proximal and distal discs <NUM>, <NUM> to be rotated opposite to their rotational shape and, therefore, rotated out of their original expanded shape, to retract or withdraw prongs <NUM> from pockets <NUM>. Thereby, frame <NUM> is "de-coupled" from biomaterial cover <NUM>.

Notably, in some embodiments, depending on the shape of frame <NUM> and/or prongs <NUM> (e.g., the thickness, stiffness, or shape of prongs <NUM>), frame <NUM> does not need to be rotated to de-couple frame <NUM> from biomaterial cover <NUM>. In such embodiments, frame <NUM> may be de-coupled from biomaterial cover <NUM> by applying only a proximally oriented force to frame <NUM>.

As frame <NUM> is being or has been de-coupled from biomaterial cover <NUM>, frame <NUM> can be withdrawn from biomaterial cover <NUM> and, therefore, medical device <NUM> at the target site, leaving only biomaterial cover <NUM> in place to provide the necessary occlusion of the target site.

In some embodiments, as shown in <FIG>, coupling member <NUM> is embodied as a loop or snare, which is advanced distally from retrieval catheter <NUM> towards connecting member <NUM> of frame <NUM> (see <FIG>). Coupling member <NUM> is attached to connecting member <NUM> by looping coupling member <NUM> around connecting member <NUM> (see <FIG>). Once coupling member <NUM> has been looped around connecting member <NUM>, the snare is retracted into retrieval catheter <NUM> (see <FIG>) and/or retrieval catheter <NUM> is advanced distally until connecting member <NUM> is secured within retrieval catheter <NUM> or a docking cap <NUM>. More specifically, a distal end <NUM> of retrieval sheath <NUM> and/or of recapture cable <NUM> is fitted with a docking cap <NUM> to secure connecting member <NUM> as frame <NUM> is withdrawn from biomaterial cover <NUM>. Retrieval catheter <NUM> or docking cap <NUM> may be advanced into engagement with medical device <NUM> (e.g., proximal disc <NUM>) to support biomaterial cover <NUM> while retracting frame <NUM> therefrom, to improve retention of biomaterial cover <NUM> within the target site during withdrawal of frame <NUM>.

In one embodiment, as shown in greater detail in <FIG>, docking cap <NUM> and connecting member <NUM> have complementary shapes. For example, docking cap <NUM> has a non-circular shape that is complementary to a shape of connecting member <NUM>, such that docking cap <NUM> is able to transfer rotational forces to connecting member <NUM>. Although these complementary shapes are depicted as generally triangular in <FIG>, it should be readily understood that various other regular and irregular non-circular shapes may be implemented (e.g., oval, rectangular, star-shaped, hexagonal, etc.). Additionally or alternatively, connecting member <NUM> may have a shape that is generally circular but that includes one or more indentations, extensions, and the like, such that the complementary shape of docking cap <NUM> may suitably impart rotational forces thereto. Once connecting member <NUM> has been secured within docking cap <NUM>, connecting member <NUM> (and, thereby, frame <NUM>) is rotated (via rotational forces from docking cap <NUM>) in second direction <NUM> to de-couple and withdraw frame <NUM> from biomaterial cover <NUM>, as described above. In some embodiments, as shown in <FIG>, this rotational force may cause frame <NUM> to twist upon itself into a reduced profile or configuration for retraction into retrieval catheter <NUM>. In other embodiments, rotation of frame <NUM> de-couples frame <NUM> from biomaterial cover <NUM>, and force applied by the distal end of retrieval catheter <NUM>, as frame <NUM> is pulled proximally thereagainst, forces frame <NUM> into a reduced configuration for retraction of frame <NUM> into catheter <NUM>.

In other embodiments, although not shown, a loop or snare may be coupled to connecting member <NUM>, and coupling member <NUM> may engage the loop or snare. Moreover, in some embodiments, for example, where connecting member <NUM> has a small diameter, retrieval catheter <NUM> does not include a docking cap, and frame <NUM> is retracted fully into retrieval catheter <NUM> during withdrawal. In still other embodiments, coupling member <NUM> includes more than one hoop or snare that are deployed simultaneously to engage connecting member <NUM>.

Turning now to <FIG> a flow diagram of a method <NUM> for recapturing a device frame from a medical device deployed at a target site in a subject is illustrated, according to one embodiment.

Method <NUM> includes locating <NUM> an expanded medical device (e.g., medical device <NUM>, shown in <FIG>) at the target site. As described herein, the medical device includes a frame having proximal and distal ends, the frame including a proximal disc at the distal end, a distal disc at the distal end, and a connecting segment having a proximal end and a distal end connecting the proximal and distal discs. Each of the proximal and distal discs includes a respective plurality of prongs, and each of the proximal and distal discs have a maximum cross-sectional dimension larger than the connecting segment. The medical device also includes at least one biomaterial cover, the biomaterial cover including an outer section and an inner section defining a cavity therebetween, wherein at least one of the proximal and distal discs of the frame is positioned in the cavity.

Method <NUM> also includes coupling <NUM> a cable (e.g., recapture cable <NUM>, shown in <FIG>) to the frame of the medical device, rotating <NUM> the cable to constrict the plurality of prongs of the frame (e.g., to de-couple the frame from the at least one biomaterial cover), and retracting <NUM> the frame from the biomaterial cover of the medical device at the target site, to capture the plurality of prongs into the retrieval sheath.

Method <NUM> may include additional, alternative, and/or fewer steps, including those described herein. For example, in some embodiments, coupling <NUM> includes attaching a coupling member at a distal end of the cable to a connecting member at a proximal end of the frame. In some such embodiments, the attaching includes looping the coupling member around the connecting member (e.g., where the coupling member is embodied as a loop or snare). Moreover, in certain embodiments, method <NUM> does not include rotating <NUM> (e.g., in embodiments in which the frame does not need to be rotated to de-couple the frame from the biomaterial cover).

In some embodiments, each of the plurality of prongs are curved into a bent star configuration in which each prong of the plurality of prongs extends radially outwardly from the connecting segment and has a radius of curvature in a first direction defined between the connecting segment and a corresponding free end of the corresponding prong. In some such embodiments, rotating <NUM> includes rotating the cable in a second direction opposite to the first direction to de-couple the plurality of prongs from the at least one biomaterial cover.

While embodiments of the present disclosure have been described, it should be understood that various changes, adaptations and modifications may be made therein without departing from the scope of the appended claims. Further, all directional references (e.g., upper, lower, upward, downward, left, right, leftward, rightward, top, bottom, above, below, vertical, horizontal, clockwise, and counterclockwise) are only used for identification purposes to aid the reader's understanding of the present disclosure, and do not create limitations, particularly as to the position, orientation, or use of the disclosure. It is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative only and not limiting. Changes in detail or structure may be made without departing from the appended claims.

Claim 1:
A medical device (<NUM>) for treating a target site comprising:
a frame (<NUM>) having proximal and distal ends, the frame comprising a proximal disc (<NUM>) at the proximal end (<NUM>), a distal disc (<NUM>) at the distal end (<NUM>), and a connecting segment (<NUM>) having a proximal end and a distal end connecting the proximal and distal discs, each of the proximal and distal discs include a respective plurality of prongs (<NUM>), each of the proximal and distal discs having a maximum cross-sectional dimension larger than the connecting segment; and
at least one biomaterial cover (<NUM>), the biomaterial cover comprising an outer section (<NUM>) and an inner section (<NUM>) defining a cavity (<NUM>) therebetween, wherein at least one of the proximal and distal discs of the frame is positioned in the cavity,
characterized in that the frame (<NUM>) is de-coupleable from the biomaterial cover (<NUM>) after deployment of the medical device at the target site.