Edge-to-edge repair device for valves

Abstract

A valve fixation device may include a unitary elongated member biased toward a closed configuration in which at least a pair of tissue engaging surfaces of the elongated member are held in a position proximal to one another by a biasing force. The biasing force is at least equal to a leaflet grasping force, thereby enabling the fixation device to grasp and retain the leaflets as part of a cardiac treatment. A delivery tool including an expander can independently translate the tissue engaging surfaces to enable the heart valve leaflets to be captured and retained between the tissue engaging surfaces. The valve fixation device may include at least two arms, each arm being independently controllable to grasp and capture opposing leaflets of a valve, such as an anterior and posterior leaflet of a mitral valve, to reduce the size of the valve opening and improve cardiac function.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority under 35 U.S.C. 119 to U.S. Provisional Patent Application No. 62 / 945,453, filed on December 9, 2019, which is incorporated herein by reference in its entirety for all purposes. Technical Field

[0003] The present disclosure relates generally to the field of implantable medical devices. In particular, the present disclosure relates to medical devices, systems, and methods for cardiac treatment. Background Art

[0004] Mitral regurgitation occurs when the native mitral valve fails to close properly, causing blood to flow backward from the left ventricle into the left atrium during the systolic phase of the heart's contraction. Mitral regurgitation can have many causes, including but not limited to leaflet prolapse, papillary muscle dysfunction or damage, congenital defects, rheumatic fever, and / or stretching of the valve annulus. Mitral regurgitation can hinder the subject's ability to process oxygen effectively, leading to fatigue and dizziness. Over time, regurgitation can lead to enlargement of the left atrium and impaired heart function. Summary of the Invention

[0005] According to one aspect, a leaflet fixation device includes a unitary elongated body comprising a proximal neck and a distal portion, the proximal neck comprising a first tissue engaging surface and the distal portion comprising an arm having a second tissue engaging surface. The arm may include an open configuration (wherein the first tissue engaging surface may be spaced apart from the second tissue engaging surface) and the arm is biased toward a closed configuration (wherein the second tissue engaging surface is held adjacent to the first tissue engaging surface by a biasing force, and wherein the biasing force may be at least equal to the leaflet grasping force).

[0006] In various embodiments, the arm can be one of a plurality of arms that are biased toward the closed configuration, and each arm of the overall elongated body can be adjacent to a different portion of the proximal neck of the overall elongated body in the closed configuration. In one embodiment, in the closed configuration, the first arm can be adjacent to a first surface of the proximal neck of the overall elongated body, and the second arm can be adjacent to a second, opposite surface of the proximal neck of the overall elongated body. In various embodiments, the proximal neck, the distal portion, or both can include a tissue retention feature. The tissue retention feature can be one of a plurality of tissue retention features disposed on the proximal neck, the distal portion, or a combination of the proximal neck and the distal portion, and is configured to penetrate but not penetrate tissue, penetrate tissue, or both.

[0007] The tissue retention features may include barbs, hooks, teeth, tines, or combinations thereof. The tissue retention features may include features that promote tissue ingrowth into the overall elongated body. Each arm of the plurality of arms may be configured to move independently from the other walls of the plurality of arms. In one embodiment, the overall elongated body includes a length and a width, and the distal portion of the overall elongated body may be divided along its width to define a plurality of arms, each arm of the plurality of arms having a common width. In one embodiment, the overall elongated body includes a length, a width, and a thickness, and the distal portion of the overall elongated body may be divided along its width to define a plurality of arms, each arm of the plurality of arms having a common width. In one embodiment, the proximal neck may be divided into a plurality of necks, and wherein the overall elongated body may include an offset configuration (wherein at least one arm may be adjacent to at least one neck). In various embodiments, the leaflet fixation device may weigh between 50-150 mg.

[0008] According to another aspect, the system includes a leaflet fixation device comprising an overall elongated body comprising a proximal neck portion comprising a first tissue engaging surface and a distal portion comprising an arm having a second tissue engaging surface. The arm comprises an open configuration wherein the first tissue engaging surface can be spaced apart from the second tissue engaging surface and the arm is biased toward a closed configuration wherein the second tissue engaging surface can be maintained adjacent to the first tissue engaging surface by a biasing force. The system also includes a delivery tool comprising an expansion mechanism for each arm configured to independently transition the arm between a closed configuration and an open configuration.

[0009] In one embodiment, the arm can be one of a plurality of arms biased toward a closed configuration, and each arm of the overall elongated body can be adjacent to a different portion of the proximal neck of the overall elongated body in the closed configuration. In some embodiments, the proximal neck of the overall elongated body, the distal portion of the overall elongated body, or both may include a tissue retention feature comprising a barb, a hook, a tooth, a spike, a hole, a texture, or a combination thereof. In one embodiment, the expansion mechanism may include a jaw pivotally coupled to a distal end of a delivery tool, the jaw comprising a connector configured to releasably couple the arm to the jaw, wherein rotation of the jaw in a first direction pulls the arm of the leaflet fixation device away from the proximal neck of the leaflet fixation device to an open configuration to provide space for valve tissue therebetween, and wherein rotation of the jaw in a second direction returns the arm to a closed configuration. In one embodiment, each expansion mechanism comprises an expansion arm rotatably coupled to a distal end of the delivery tool, the expansion arm being arranged to urge the arm of the leaflet fixation device away from the proximal neck of the leaflet fixation device to an open configuration, wherein rotation in a first direction provides space for valve tissue therebetween, wherein rotation of the expansion arm in a second direction returns the arm to a closed configuration. In one embodiment, the proximal neck of the leaflet fixation device, the distal arm, or both include tissue retention features, and the expansion mechanism can be configured to independently transition the arm between the closed and open configurations and prevent engagement of the tissue engagement features with tissue during placement of the leaflet fixation device.

[0010] According to another aspect, a method for connecting leaflets of a heart valve includes the step of advancing a delivery tool carrying a fixation device at its distal end toward a valve treatment site; the fixation device includes a unitary elongated body including a proximal neck and a distal portion including an arm, wherein the arm includes an open configuration (wherein the proximal neck of the unitary elongated body can be spaced from the arm) and a closed configuration (wherein the arm can be maintained in a position adjacent to the proximal neck of the unitary elongated body by a biasing force, and wherein the arm can be biased in a static state in the closed configuration). The method includes: positioning the delivery tool proximate to a first leaflet, thereby actuating an expansion mechanism of the delivery tool so as to angularly displace the arm in a direction away from the proximal neck of the unitary elongated body to the open configuration, thereby positioning the proximal neck of the unitary elongated body and the arm on opposite sides of the first leaflet and actuating the expansion mechanism to restore the arm to the closed configuration.

[0011] In some embodiments, the arm can be a first arm of a pair of arms biased toward a closed configuration, and the method may include positioning a delivery tool proximate the second leaflet, actuating an expansion mechanism of the delivery tool to angularly displace the second arm in a direction away from the proximal neck of the integrally elongated body into an open configuration, positioning the proximal neck of the integrally elongated body and the second arm on opposite sides of the second leaflet and actuating the expansion mechanism to return the second arm to the closed configuration.

[0012] This arrangement provides a lightweight, unitary leaflet clip for securing valve leaflets for cardiac repair. Utilizing a unitary body to form the leaflet clip reduces the number and type of components associated with the leaflet clamping solution, thereby reducing the overall weight of the fixation device and the risk of failure associated with long-term interaction between the components. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Non-limiting embodiments of the present disclosure are described herein by way of example and with reference to the accompanying drawings, which are schematic and not intended to be drawn to scale. In the drawings, each identical or nearly identical illustrated component is generally represented by a single numeral. For clarity, not every component is labeled in every drawing, nor are every representative component of each embodiment shown where not necessary for illustration, to allow those skilled in the art to understand the present disclosure. In the drawings:

[0014] Figure 1A-Figure 1D is a perspective view of one embodiment of a valve fixation device disclosed herein;

[0015] Figures 2A-2D is a perspective view of one embodiment of a valve fixation device disclosed herein;

[0016] Figure 3A-3C is a perspective view of one embodiment of a valve fixation device disclosed herein;

[0017] Figure 4 One embodiment of a valve fixation device disclosed herein is illustrated.

[0018] Figure 5 One embodiment of a valve fixation device disclosed herein is illustrated.

[0019] Figure 6 One embodiment of a valve fixation device disclosed herein is illustrated.

[0020] Figure 7 One embodiment of a valve fixation device disclosed herein is illustrated.

[0021] Figure 8 One embodiment of a valve fixation device disclosed herein is illustrated.

[0022] Figure 9 One embodiment of a valve fixation device disclosed herein is illustrated.

[0023] Figure 10 One embodiment of the valve fixation device disclosed herein is illustrated.

[0024] Figures 11A-11F Various configurations and features of embodiments of delivery mechanisms for delivering the valve fixation devices disclosed herein in various embodiments to a valve treatment site are illustrated.

[0025] Figures 12A-12C Various configurations of one embodiment of a delivery mechanism for delivering the valve fixation device disclosed herein in various embodiments to a valve treatment site are illustrated.

[0026] Figures 13A-13D Examples of steps that may be performed for heart valve treatment using the valve fixation devices disclosed herein in various embodiments are illustrated.

[0027] Figure 14 is a top-down perspective view of the mitral valve after delivery of a leaflet fixation device as disclosed herein. DETAILED DESCRIPTION

[0028] The present disclosure provides methods and apparatus for grasping and securing tissue (e.g., leaflets) to treat heart valve regurgitation. In one embodiment, a valve fixation device may include an integrally elongated member comprising at least one neck portion and at least one arm portion, the elongated member being biased toward a closed configuration (wherein a biasing force is utilized to maintain at least one pair of tissue engaging surfaces of the elongated member, e.g., a tissue engaging surface on the neck portion and a tissue engaging surface on the arm portion, in an adjacent position to one another). The biasing force is at least equal to the leaflet grasping force, thereby enabling the fixation device to grasp and retain the leaflets as part of a cardiac treatment. A delivery tool including an expander may independently translate the tissue engaging surfaces so that the heart valve leaflets can be captured by and retained between the tissue engaging surfaces. The valve fixation device may include at least two arms, each arm being independently controllable to grasp and capture opposing leaflets of a valve (e.g., anterior and posterior leaflets of a mitral valve) to reduce the size of the valve opening and improve cardiac function. In some embodiments, at least a portion of the fixation device includes one or more tissue retention structures, including but not limited to teeth, barbs, hooks, spikes, holes, or surface textures that improve the retention performance of the fixation device. In some embodiments, the delivery tool may include one or more features (such as guards or nut standoffs) that are configured to reduce interaction between the tissue retention structure and tissue during positioning of the fixation device.

[0029] These and other advantageous aspects of the implant and method of placement are described in greater detail below. Although embodiments of the present disclosure may be described with particular reference to the mitral valve, the principles disclosed herein may be readily adapted to facilitate reconstruction of any valve annulus (e.g., including the tricuspid annulus) and / or may similarly benefit any other dilatation, valvular insufficiency, valvular leakage, and other similar heart failure conditions.

[0030] As used herein, the term "distal" refers to the end of the medical device farthest from the medical professional when introduced into the patient, while the term "proximal" refers to the end of the medical device closest to the medical professional when introduced into the patient.

[0031] Figure 1A-Figure 1D A perspective view of one embodiment of a fixation device 100, as disclosed herein, is shown. The fixation device 100 can be used to reduce the size of a valve, for example, by connecting the leaflets together. The fixation device 100 is shown as being comprised of a unitary, elongated body 105 having a proximal neck 110 and a distal portion 130 comprising one or more arms of the elongated body. In various embodiments, the body 105 can be made of a shape memory alloy (SMA) or a similar material having the ability to return to a predetermined configuration. Such materials include, but are not limited to, nickel-titanium alloys, graphene, nitinol, copper-aluminum-nickel alloys, and the like.

[0032] Such a material is referred to herein as biased toward a predetermined configuration. The biasing force is the restoring force of the shape memory alloy, for example, the force exhibited by the body recovering (e.g., returning to its predetermined configuration) under the action of strain that results from deformation from the predetermined configuration. The biasing force is a function of the size, shape, and composition of the forming material. In an exemplary embodiment, the overall elongated body may have a length of 14 mm to 24 mm to provide a "folded" length between 7 mm and 12 mm, a width of 2 mm to 6 mm, and a thickness of 0.25 mm to 0.75 mm, thereby providing a device with a gripping force between 0.1 lb and 0.5 lb. Although fixtures having various ranges of lengths, widths, and / or thicknesses are disclosed, it should be understood that those skilled in the art may develop similar fixtures that are capable of providing similar biasing forces or gripping forces that urge the fixture toward a closed tissue-retaining configuration, and such similar devices are considered to be within the scope of the present disclosure.

[0033] According to one aspect, the fixation device can be manufactured to provide sufficient gripping force to enable it to be securely attached to the leaflet tissue without imparting excessive weight that could affect the rest of the valve function. Thus, the fixation device has a mass that is not significantly greater than necessary, such that the weight of the fixation device does not negatively impact the leaflets or nearby tissue. For example, the weight of the device 100 can be between 50 mg and 150 mg, such as 65 mg, etc., such that the weight of the clip does not undesirably interfere with leaflet operation.

[0034] Figure 1A The unitary elongated body 105 is shown in an unbiased state. In one embodiment, the unitary elongated body 105 has a length L extending longitudinally along an axis A, a width W perpendicular to the axis A, and a thickness T. In some embodiments, as Figure 1A As shown in , the width is constant along the length L. In other embodiments, the width may vary (increase, decrease) along the length L. Similarly, although the thickness T is shown as being relatively consistent along the length and width, it should be understood that in various embodiments, the thickness may vary (increase, decrease) along the length L or along the width W. Figure 1A In the embodiment of FIG. 1 , as will be described in greater detail below, the distal portion 130 of the unitary elongated body 105 is shown divided across its width into a plurality of arms, such as arm 120 and arm 122 .

[0035] The overall elongated body has several surfaces including Figure 1A The front surface 112 shown in FIG, and the rear surface 111 (shown in FIG Figure 1C ). At least a portion of the proximal neck 110 of the unitary elongated body 105 includes a tissue engaging portion 115, and at least a portion of the distal end of the arms (such as arm 120) also includes a tissue engaging surface portion 125. Although certain portions of the body 105 are designated as tissue engaging surfaces, it should be understood that the tissue engaging surface portion may include an area larger or smaller than that designated area, and the tissue engaging portion may be any surface of the body 105 that contacts leaflet tissue during use.

[0036] According to one embodiment, the predetermined configuration of the unitary elongated body includes a closed configuration wherein common surfaces of the proximal and distal portions of the unitary elongated body are positioned proximate and opposite each other to form the leaflet fixation device.

[0037] For example, Figure 1BThe unitary elongated body 100 is illustrated in its biased, closed configuration. Each arm 120, 122 is biased differently, formed so that the distal ends 121, 123 of each arm 120, 122 contact different surfaces (e.g., 111, 112) of the proximal neck 110 of the leaflet fixation device 100. For example, the distal end 121 of arm 120 contacts the proximal neck 110 of the device 100 at the tissue-engaging surface 115, while the distal end 123 of arm 122 contacts the proximal neck 110 of the device 100 at the opposite surface. Thus, the fixation device 100 utilizes the resistance of the shape memory material to provide an overall low-profile, lightweight retention mechanism for leaflet treatment.

[0038] Figure 1C Illustrated is a rearward-facing surface 111 of the fixation device 100 , which includes offset arms 120 , 122 and is shown including a tissue-engaging surface 117 on a proximal end 110 thereof. Figure 1A-Figure 1D The embodiment of the fixation device 100 includes a retaining device with two arms, wherein each of the arms is biased toward an opposite surface of the proximal neck of the body 105. Thus, the distal tissue engaging surface 127 of the arm 122, in the biased configuration, contacts or is adjacent to and faces the tissue engaging surface 117. Figure 1C 105 to an angle 133. This angle 133 corresponds to an open configuration of the arms 122 that leaves a gap between the body 105 and the arms 122 that is sufficiently wide to allow leaflet tissue to be positioned therebetween. In some embodiments, the angle 133 may be in the range of 75 degrees to 120 degrees or more, for example, to leave a gap of approximately 90 degrees.

[0039] Figure 1D is a schematic diagram illustrating the fixation device 100 in a fully open configuration, wherein the two arms 120, 122 are spaced from the proximal neck 110 such that the distal tissue engaging surfaces 125, 127 are spaced from the proximal tissue engaging surface 117. As described in more detail below, according to one aspect, each of the arms 120, 122 of the fixation device 100 can be independently opened and closed, thereby enabling tissue to be grasped with greater precision and accuracy by enabling grasping of individual leaflets during a procedure.

[0040] exist Figure 1A-Figure 1D In embodiments where the arms of the distal portion of the unitary elongated body are formed by dividing the width of the distal portion into segments, the distal tissue engaging surface (125, 127) comprises only approximately half (or other fraction, if the arms have different widths) of the width W of the unitary body 105. In such a configuration, the gripping force of each arm should be selected to compensate for the reduced size of the tissue engaging surface.

[0041] Figure 2A-2D Various views of a second embodiment of a fixture 200 are shown that includes a unitary elongated body 205 having a length L, a width W, and a thickness T that correspond in the L and W dimensions to Figure 1A-Figure 1D The device 100 may have a thickness T that can range from the same size to twice or more than twice the thickness at least partially along its length, as will be described below. Figure 2A , the body 205 is shown in an unbiased configuration. The body 205 includes a proximal neck 210 including a tissue-engaging surface 215 and a distal portion 230 including a tissue-engaging surface 225. In some embodiments, the thickness of the distal portion 230 can be greater than the thickness of the proximal neck 210, although the present disclosure is not limited in this regard. The arms 220, 222 of the fixation device 200 can be formed by dividing the thickness T of the distal portion into segments. Due to this arrangement, the tissue-engaging surface area 225 of the distal end 230 of the fixation device 200 utilizes the entire width W of the body 205, thereby more fully utilizing the proximal tissue-engaging portion 215 to secure tissue. In some embodiments, increasing the tissue-engaging surface area in this manner enables lightweight materials to be used in the fixation device, while achieving the desired biasing force for leaflet grasping.

[0042] Figure 2B is a side view of the fixation device 200. The figure shows that the distal portion 230 of the device 200 is bisected along its thickness T, thereby forming two arms 220, 222 biased toward the closed configuration, wherein the distal ends of the arms 220, 222 contact or are adjacent to and face opposite surfaces of the proximal neck 210 of the device 200.

[0043] Figure 2C Device 200 is illustrated in a partially open configuration, wherein arms 220 have been pulled or pushed back from the biased closed configuration to expose distal tissue engaging surface 227 and proximal tissue engaging surface 217 (not visible) to leaflet tissue.

[0044] Figure 2D The device 200 is illustrated in a fully open configuration, wherein the two arms 220, 222 have been pushed or pulled away from their biased closed configuration to an open configuration (wherein the gaps G1, G2 enable leaflet tissue to be captured between the tissue engaging surfaces of the device 200).

[0045] Figure 3A-3C An alternative embodiment of a fixture 300 is shown. Figure 2A-2C The device 200, Figure 3A-3CThe device includes arms 320, 322 formed by bisecting the distal portion of the elongated body 305 along its thickness. The arms 320, 322 are biased toward a closed configuration in which the distal portions of the arms 320, 322 contact or are adjacent to and face the proximal neck 310 of the body 305. Figure 3A 、 Figure 3C In the embodiment of the present invention, the proximal neck 310 of the body 305 includes one or more tissue retention features (tissue retention structures), such as tissue retention feature 323. Figure 3A-3C 3 , tissue retention features 323 are shown disposed on opposing surfaces 311, 312 of the proximal neck 310 of the elongated body 305. The illustrated tissue retention features 323 include teeth extending at an angle relative to the longitudinal axis A of the elongated body. In one embodiment, when disposed between the arms 320, 322 and the proximal tissue engaging surface, the teeth are angled distally to secure the leaflet tissue against pullout due to chronic palpatory forces.

[0046] In some embodiments, the one or more tissue retention structures can be arranged in multiple rows along at least one of the multiple arms, such that the multiple retention mechanisms are in different planes. The protrusions can extend no more than 50% of the thickness of the leaflet wall, for example, the protrusions can deform the tissue without extending into the leaflet wall. The protrusions can extend from the arm a distance that can be about 0.5 mm to about 1.5 mm.

[0047] Figure 3B is a cross-sectional view of the device 300 illustrating the tissue retention structure 323 disposed on opposing surfaces 311, 312 of the proximal end 310 of the device 300. Figure 3B As shown in , when arms 320, 322 are urged toward their biased configurations, each arm pushes any captured tissue toward tissue retaining structure 323, thereby improving the conformation of device 300 to the leaflet tissue. Figure 3C Device 300 is shown in a fully open configuration, providing gaps G1, G2 between the proximal end 310 of device 300 and the respective arms 320, 322. It will be appreciated that when tissue-retaining structures (such as teeth 323) are employed, the elasticity of the overall elongated body can be selected to ensure that gaps G1, G2 are wide enough to accommodate leaflet tissue without interaction from retaining mechanism 323. In other words, the open configuration should provide a gap that is at least equal to the expected leaflet tissue thickness plus the protrusion of any tissue-retaining structure used to retain the leaflets.

[0048] although Figure 3A-3CWhile the tissue retention features are shown relatively evenly disposed on opposing surfaces of the proximal neck 310 of the body 305, it should be understood that the tissue retention features may take many shapes and may be arranged in a variety of patterns optimized for the specific tissue being captured by the fixation device and for securing the device against chronic palpation forces acting thereon. Figure 3A-3C Specifically shaped teeth are shown in , but the present disclosure is not limited to the use of teeth, but may alternatively include barbs, hooks, spikes, or other features that may be used to engage or interact with leaflet tissue.

[0049] Figure 4-Figure 7 Various embodiments of tissue retention devices employing different tissue retention structures are illustrated. Figure 4 is a cross-sectional view of one embodiment of a device 400 including a plurality of tissue-retaining structures disposed on a proximal neck 401 of the device 400, including distally facing teeth 402 and proximally facing teeth 404. Such an embodiment may improve the ability of tissue to be grasped between the proximally facing teeth and the distally facing teeth to help the device 400 retain leaflet tissue.

[0050] Figure 5 is a cross-sectional view of one embodiment of a device 500 including multiple tissue retention structures, wherein some tissue retention structures (e.g., neck teeth 512) are disposed on the proximal neck 501 of the device 500, and other tissue retention structures (e.g., tissue engaging teeth 515) are disposed on arms 514, 516. Due to this arrangement, tissue retention is applied on both sides of the captured leaflets, thereby further increasing the strength of the fit of the fixation device 500 to the leaflets.

[0051] Figure 6 is a cross-sectional view of an embodiment of a device 600 comprising a plurality of tissue retention structures, some of which (e.g., neck teeth 622, 624) are disposed on a proximal neck 601 of the device 600, while other tissue retention structures (e.g., tissue engaging teeth 625) are disposed on arms 626, 628. Figure 6 The embodiments illustrate how the pattern of the tissue retention structure can be changed based on the specific tissue or long-term use of the clip.

[0052] Figure 77 is a side perspective view of an embodiment of a device 700 including multiple tissue retention structures, including two tissue retention structures configured to pierce tissue (such as neck teeth 702, 703 on the proximal neck 701), and tissue engaging teeth 705 on arms 704, 706, and tissue retention structures such as holes 707 configured to promote endothelialization (e.g., tissue ingrowth) into the device 700. For example, the pore size can range between 5 μm and 30 μm. The holes can be distributed along a portion or all of the elongated body. Other methods of promoting tissue ingrowth along a portion or all of the elongated body (e.g., by changing the surface texture of the elongated body, coating the body with a pro-angiogenic drug, etc.) are also within the scope of the present disclosure.

[0053] Figures 8-10 An alternative embodiment of a tissue fixation device is illustrated that may be constructed of a resilient material that utilizes a biasing force in a closed configuration to provide a leaflet gripping force to retain the leaflets within the device.

[0054] Figure 8 The figure shows a fixation device 800 including an elongated body 805 formed into two opposing arms 820, 822 and curved so that the proximal end 810 of the elongated body faces the distal end 830 of the elongated body, and the arm portions 821, 823 are biased to a closed configuration so that the tissue engaging surfaces 811, 813 of the arms are adjacent and facing each other to enable tissue to be grasped between the arms 820, 822. Each arm 820, 822 is shown including tissue retaining structures (such as teeth 802) arranged in parallel rows along the surface 811, 813 of the device 800. Figure 8 In an embodiment, the proximal end 810 and the distal end 830 of the elongated body 805 can each include a coupler 832, 833 that can be used, for example, to couple the device 800 to a delivery tool to control delivery of the device 800 to the leaflets. As described in more detail below, in one embodiment, the coupler 832 can include a hole (not shown) having a central lumen 835 extending therethrough that is configured to receive a pin or other mechanism to releasably secure the arm to a delivery tool configured to move each arm 820, 822 independently of the other arms of the body 805.

[0055] Figure 9is a side view of one embodiment of a fixation device 900 comprised of a unitary elongated body 905 that has been split along its thickness to form two proximal arms 910, 912 in the proximal neck of the elongated body 905 and distal arms 920, 922 in the distal portion of the elongated body 905. In one embodiment, the distal arm 920 includes a biased configuration in which a distal tissue engaging surface 925 is adjacent to and facing the proximal tissue engaging surface 915 of the proximal arm 910. The distal arm 922 also includes a biased configuration in which a distal tissue engaging surface 927 is adjacent to and facing the proximal tissue engaging surface 917 of the proximal arm 912. Such a fixation device can be used to reduce strain on the leaflets by allowing the fixation portion to move more freely with the valve during use while providing the force necessary to maintain the leaflets in a connected configuration to treat disease. Figure 9 In the embodiment shown, each proximal arm 910, 912 includes tissue retention structures (such as teeth 924) arranged along its length. Figure 4-Figure 7 As described, additional or alternative tissue retention structures and patterns may be substituted herein, consistent with the present disclosure.

[0056] Figure 10 is a side view of an embodiment of a fixation device 1000 comprised of an integral elongated body 1005 that has been portioned along its thickness to provide a plurality of distal arms 1020, 1022, 1030, 1032, each distal arm being biased in a closed configuration in which the distal tissue engaging surfaces 1021, 1023, 1031, 1033 are oriented toward the tissue engaging surface of the proximal neck 1010 of the body 1050. In one embodiment, connectors 1021, 1023 may be used to couple the inner distal arms 1030, 1032 to the outer distal arms 1020, 1022 so that when the outer distal arms 1020, 1022 are deployed, the inner distal arms 1030, 1032 are pulled apart, thereby allowing tissue to be positioned between the proximal neck 1010 of the body 1050 and the arms 1020, 1030, 1022, 1032. Figure 10 As shown in FIG, tissue retention structures (eg, teeth 1011, 1013) may be strategically placed along the proximal neck 1010 and / or arms 1020, 1022, 1030, 1032 to secure tissue within the device 1000.

[0057] Leaflet retaining devices (as described in the various embodiments above) can be used in a variety of procedures, including endovascular, minimally invasive, and open surgical procedures, and can be used in a variety of anatomical regions, including the abdomen, chest, cardiovascular system, heart, intestines, stomach, urinary tract, bladder, lungs, and other organs, vessels, and tissues. These fixation devices are particularly useful in procedures requiring minimally invasive or endovascular access to remote tissue locations, where the instruments must navigate long, narrow, and tortuous pathways to reach the treatment site.

[0058] For example, the leaflet fixation device can be used for edge-to-edge repair of a heart valve, including but not limited to the mitral valve. The mitral valve can be approached from a remote surgical site or a vascular access point, and the two leaflets can be joined together at the fixation point using an intravascular or minimally invasive method using a fixation device. For example, the fixation device can be used to connect the anterior leaflet and the posterior leaflet of the mitral valve at any position of the leaflet between the lateral and medial commissures of the valve. Multiple fixation devices can be used to connect the leaflets at various points of the valve. In some cases, the fixation device can also be used for open surgical approaches. According to the present invention, the mitral valve can be approached from the atrial side (antegrade approach) or the ventricular side (retrograde approach) and through a blood vessel or through the heart wall.

[0059] The fixation device can be delivered using a tool positioned near the desired treatment site and used to manipulate the fixation device so that it can grasp the target tissue. In intravascular applications, the delivery tool can typically be a working catheter that is translated to the treatment site using a delivery catheter / guidewire system. In surgical applications, the delivery tool can typically be a surgical instrument.

[0060] In one embodiment, the method includes the steps of advancing a delivery tool having a proximal end and a distal end to a position located within the patient's body, wherein the delivery tool releasably carries a fixation device and is configured to transition the fixation device between its open configuration and a closed configuration to grasp leaflet tissue and release the leaflet tissue after positioning the fixation device on the leaflet.

[0061] Figures 11A-11E Features of one embodiment of a delivery tool 1100 that can be used to deliver a fixation device 1150 to a treatment site are illustrated. The delivery tool 1100 is shown to include a support arm 1120 having a proximal end 1101 and a distal end 1103. The distal end 1103 has an opening defining a cannula configured to releasably receive a proximal neck 1110 of the fixation device 1150. In some embodiments, for example, the proximal neck 1110 of the fixation device can include a slot that cooperates with a tab (not shown) within the cannula to retain the proximal neck 1110 of the fixation device within the cannula during placement. After placement, the tab can be removed from the slot, thereby releasing the fixation device from the delivery tool.

[0062] Conveyor 1100 also comprises one or more expansion mechanisms (as claws 1152,1154).Each claw 1152,1154 mates substantially with the curve of fixture 1150 in shape, so that the profile of this conveyor is minimized.In one embodiment, claws 1152,1154 comprise curved shape, so that the possibility of interference occurs between the far-end 1103 of conveyor and cardiac features (as chordae tendineae etc.) is minimized.In one embodiment, each claw 1152,1154 is pivotally mounted to the far-end 1103 of the support arm 1120 of conveyor 1100 at its far-end pivot point 1156.Guide cables 1122,1124 can extend to the far-end 1103 of the support arm 1120 of conveyor 1100 from the near-end of claws, wherein actuating described drive cable, for example, pulling described cable to the proximal side by sleeve, can pull claws 1152,1154 away from the longitudinal axis limited by conveyor. In one embodiment, the distal arms of the fixation device 1150 are releasably coupled to the proximal ends of the jaws 1152, 1154 such that when the jaws are pulled away from the longitudinal axis of the delivery tool, the distal arms are also pulled away, thereby creating a gap that can be used to grasp the leaflet tissue.

[0063] For example, Figure 11B The delivery tool 1100 is shown supporting the fixation device 1150 in a partially open configuration, wherein the jaws 1154 are releasably coupled to the distal arms 1155 of the fixation device 1150 at their proximal ends 1157. The guide cables 1124 are pulled into the support arms 1120 to open the jaws 1154, thereby forming a gap G1 for receiving the leaflet tissue. The guide cables 1124 can then be released or actuated, allowing the arms 1155 to return to their biased closed configuration to capture the leaflet tissue between the arms 1155 and the proximal neck 1110 of the fixation device 1150.

[0064] Figure 11C The diagram illustrates the actuation of the second jaw 1152, which is generated, for example, by manipulating the guide cable 1122 (described above) passing through the support arm 1120. When the guide cable 1122 is pulled proximally through the support arm 1120, the jaw 1152 opens. The distal arm 1159, which is releasably coupled to the jaw 1152, is also pulled away from the proximal neck 1110 of the fixture 1150 by the action of the jaw, thereby creating a gap G2 for capturing the second leaflet. Once the leaflet is positioned within the gap G2, the guide cable 1122 can be released or controlled to allow the side arm 1159 to return to its biased configuration, thereby capturing tissue between the arm 1159 and the proximal neck 1110 of the device 1150.

[0065] Figure 11D1163 is an enlarged cross-section of one example of a system for coupling the distal arm 1159 to the jaw 1152. In one embodiment, as described above, the distal arm can have a coupler 1162 disposed at its distal end. The coupler can include, for example, a protrusion having a hole 1163 extending therethrough, wherein the hole is sized to receive the distal end of the guide cable 1122. In some embodiments, the guide cable 1122 can include a drive tube thereof having a threaded coupler 1134 disposed on its distal end 1125. The threads of the coupler can interact with threads or other features on the inner surface of the hole 1163 to secure the threaded coupler 1134 within the interior of the hole 1163. In some embodiments, the drive tube can be rotatable, and rotation of the drive tube causes the drive tube to translate axially within the interior of the hole 1163. Once the fixation device has been manipulated to grasp both the anterior and posterior leaflets, the drive device can be actuated to translate the drive tube distally through hole 1163, thereby releasing the connection between the arms 1159 of the fixation device and the jaws 1152 of the delivery tool and allowing removal of the delivery tool from the treatment site.

[0066] In some embodiments, the connection between the delivery tool and the fixation device can be formed to prevent attachment of the fixation device during its placement, thereby facilitating positioning of the fixation device on the leaflet without tissue interaction. Figure 11E 1 is a close-up view of one embodiment of a jaw 1152 of a delivery tool including a cannula 1170 disposed longitudinally along at least a portion of the jaw's length. In one embodiment, cannula 1170 provides a standoff that maintains a space between a tissue retaining structure and an opposing tissue engaging surface to prevent the tissue retaining structure from entering the tissue during positioning of the fixation device. The height H of cannula 1170 is 100 mm. STANDOFF May generally correspond to the protrusion distance of any tissue retaining structure of the fixation device.

[0067] For example, Figure 11F The figure shows a fixture 1180 arranged on the jaw portion 1152 of the delivery system. The figure shows that the fixture 1180 includes tissue retention features (e.g., teeth) 1183, which are arranged along the edge of the device 1180 and are oriented and protruding toward the tissue engaging surface 1185 of the fixture 1180. The sleeve 1170 is configured to at least partially block the entry of the teeth 1183. For example, the sleeve may have a height that is at least equal to half the protrusion distance of the teeth 1183. In some embodiments, the sleeve 1170 may include a hole 1187 extending therethrough, for example, to slidably receive a cable (not shown) that opens and closes the jaws of the delivery tool. It should be noted that although in Figure 11E and Figure 11FAn integral sleeve is shown in FIG, but alternative methods of preventing tissue adhesion during placement of the fixation device (including but not limited to separate spacers arranged along the length of the jaws, guards arranged on the tissue retention structure, etc.) are considered to be within the scope of the present disclosure.

[0068] Figures 12A-12C An alternative embodiment of a delivery tool 1200 that can be used to deliver a fixation device 1250 (as described herein in various embodiments) to a treatment site is illustrated. The delivery tool includes a proximal end 1201 and a distal end 1203, and a pair of extension arms 1230, 1232 rotatably disposed on the distal end 1203 of the delivery tool, wherein the extension arms are operable to push the distal arms 1220, 1222 of the fixation device 1250 away from the longitudinal axis defined by the delivery tool, thereby creating a gap between the tool 1200 and the arms 1220, 1222 for enclosing leaflet tissue. In some embodiments, the delivery tool may include a distal cannula configured to releasably deliver the proximal neck 1201 of the fixation device to the treatment site. In various embodiments, each expansion arm can be rotatably coupled to the proximal end 1201 of the delivery tool (e.g., at pivot points 1211, 1213) and adapted to move smoothly over the inner surfaces 1241, 1243 of the arms 1220, 1222. For example, in one embodiment, each expansion arm 1230, 1232 can include rollers 1240, 1242 disposed on its distal end that enable the expansion arm to slide smoothly over the surfaces 1241, 1243 while providing a thrust that acts on the arm in the biased configuration to create a gap. It will be appreciated that the length of each expansion arm can vary based on the particular configuration of the fixture, but should be sufficient to allow the expansion arm to create a gap that can accommodate leaflet tissue as each expansion arm rotates about its pivot point.

[0069] For example, now refer to Figure 12B , the delivery device is shown in a partially open position, wherein the extension arm 1232 has been rotated across the surface 1241 of the distal arm 1222 to a position generally perpendicular to the axis of the delivery device. The rotational force of the extension arm is sufficient to offset the biasing force of the securing device 1250, thereby causing the distal arm 1222 to be pushed away from the delivery tool 1200 and creating a gap G1 between the tool 1200 and the distal arm 1222 for receiving tissue. When tissue has been enclosed between the tool 1200 and the distal arm 1222, the extension arm 1232 can be rotated distally, thereby removing the offsetting force and allowing the distal arm 1222 to return to its biased configuration, thereby capturing the tissue between the tool 1200 and the distal arm 1222.

[0070] Figure 12CThe delivery device is shown in a partially open position, wherein the extension arm 1230 has been rotated across the surface 1243 of the distal arm 1220 to a position generally perpendicular to the axis of the delivery tool 1200. The rotational force of the extension arm 1230 counteracts the biasing force of the fixation device 1250, causing the distal arm 1220 to be pushed away from the delivery tool 1200 and creating a gap G2 between the tool 1200 and the distal arm 1220 for receiving tissue. When tissue has been enclosed between the tool 1200 and the distal arm 1220, the extension arm 1230 can be rotated distally, thereby removing the counteracting force and allowing the distal arm 1220 to return to its biased configuration to capture tissue between the tool 1200 and the distal arm 1220.

[0071] Once the two leaflets are secured, the delivery tool can be removed, for example by releasing or ejecting the proximal end of the fixation device 1250 from the delivery tool 1200.

[0072] Figures 13A-13D Various structures of a heart 1300 are illustrated, including a mitral valve 1320 comprising posterior leaflets 1322 and anterior leaflets 1324 supported by chordae tendineae 1325, which are controlled by papillary muscles 1326. In the illustrated embodiment, a delivery catheter 1400 supports a delivery tool 1450 and can be used to guide the delivery tool 1450 to a treatment site, such as beneath the mitral valve annulus 1340.

[0073] exist Figure 13A 14. Delivery tool 1450 is shown being delivered through the atrium to the valve leaflets, although the present disclosure is not limited to any particular delivery route. The circular structure of delivery tool 1450 reduces the likelihood of interaction between the chordae tendineae and the delivery tool. Figure 13B The delivery tool 1450 is shown after the leaflets 1324 have been captured by the fixation device. Figure 13C ), the delivery tool 1450 can be used to pull the leaflet 1324 toward the leaflet 1322, for example until the two leaflets coapt. The delivery tool 1450 can then be operated to separate and close the expansion mechanism to capture the second leaflet 1322 inside the retaining device.

[0074] Figure 13D After the transport tool is removed Figure 13C An enlarged side view of the connecting leaflets is shown in FIG. Figure 13D As shown in , after delivery, the fixation device 1350 is positioned so that the leaflets 1322 , 1324 are securely captured between the proximal end 1310 of the fixation device 1350 and the arms 1352 , 1354 of the fixation device 1350 . Figure 14is a top-down view of the mitral valve after placement of fixation device 1450 between anterior leaflet 1402 and anterior leaflet 1404 .

[0075] Thus, a unitary, lightweight leaflet is provided for securing a valve leaflet for use in a cardiac repair procedure as illustrated and described in the various embodiments. Due to this arrangement, the number and type of components associated with the leaflet clamping scheme are reduced to a single, unitary component that utilizes the resistance of a shape memory material as a securing mechanism, thereby reducing the overall weight of the securing device and the risk of failure associated with long-term interaction between the components.

[0076] As used herein, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. The words "include" and / or "comprise" or "have" when used herein specify the presence of stated features, regions, steps, elements, and / or components, but do not preclude the presence or addition of one or more other features, regions, integers, steps, operations, elements, components, and / or combinations thereof.

[0077] The conjunction "and" used in this article includes each structure, component, feature, etc. that is so joined, unless the context clearly indicates otherwise, and the conjunction "or" includes one or other of the structure, component, feature, etc. that are so joined, individually and in any combination and quantity, unless the context clearly indicates otherwise. All numerical values ​​herein are assumed to be modified by the word "about", whether or not clearly indicated. The word "about" generally refers to a series of digits that a person skilled in the art will consider to be equivalent to the enumerated value (that is, having the same function or result) in the context of numerical value. In many cases, the word "about" may include digits that are rounded to the nearest significant figure. Other uses of the word "about" (that is, in the context except for numerical value) may assume that they have their common and usual definitions, as understood therefrom and consistent with the context of this specification, unless otherwise stated. Statements of numerical ranges using endpoints include all digits within the range, including the endpoint (e.g., 1 to 5 including 1, 1.5, 2, 2.75, 3, 3.80, 4, and 5).

[0078] It should be noted that references in this specification to "one embodiment," "some embodiments," "other embodiments," etc., indicate that the described embodiments may include a particular feature, structure, or characteristic, but not every embodiment may include that particular feature, structure, or characteristic. Moreover, such phrases do not necessarily refer to the same embodiment. In addition, when a particular feature, structure, or characteristic is described in conjunction with one embodiment, it will be within the knowledge of those skilled in the art to implement such feature, structure, or characteristic in conjunction with other embodiments, whether or not explicitly described, unless explicitly stated to the contrary. That is, the various individual elements described herein, even if not explicitly shown in a particular combination, are conceivably combined or arranged with each other to form other additional embodiments or to supplement and / or enrich the described embodiments, as will be understood by those skilled in the art.

[0079] In light of the present disclosure, the devices and / or methods disclosed and claimed herein can be made and implemented without undue experimentation. Although various embodiments of the devices and methods of the present disclosure have been described, it will be apparent to those skilled in the art that changes may be made to the devices and / or methods and the steps or order of steps of the methods described herein without departing from the concept, spirit, and scope of the present disclosure. All such similar substitutions and modifications apparent to those skilled in the art are deemed to be within the spirit, scope, and concept of the present disclosure as defined by the appended claims.

Claims

1. A leaflet fixing device, comprising: a unitary elongated body comprising a proximal neck portion including a first tissue engaging surface and a distal portion including an arm having a second tissue engaging surface; the arm comprising an open configuration wherein the first tissue engaging surface is spaced away from the second tissue engaging surface; the arms being biased toward a closed configuration wherein the second tissue engaging surface is held proximate to the first tissue engaging surface by a biasing force; wherein the biasing force is at least equal to the leaflet grasping force; wherein the arm is one of a plurality of arms biased toward the closed configuration, and wherein in the closed configuration, each arm of the unitary elongated body is proximate a different portion of a proximal neck of the unitary elongated body; and wherein the overall elongated body comprises a length and a width and the distal portion of the overall elongated body is separated along its width to define the plurality of arms, each of the plurality of arms having a common thickness; or wherein the overall elongated body comprises a length, a width and a thickness and the distal portion of the overall elongated body is separated along its thickness to define the plurality of arms, each of the plurality of arms having a common width.

2. The leaflet fixing device according to claim 1, wherein: In the closed configuration, the first arm is proximate a first surface of the proximal neck of the unitary elongated body and the second arm is proximate a second, opposing surface of the proximal neck of the unitary elongated body.

3. A leaflet fixation device as described in any one of claims 1 to 2, wherein the proximal neck, the arms of the distal portion, or both include tissue retention features configured to pierce but not penetrate tissue, penetrate tissue, or both.

4. The leaflet fixation device of claim 3, wherein the tissue retention feature is one of a plurality of tissue retention features arranged on the proximal neck, the arm of the distal portion, or a combination of the proximal neck and the arm of the distal portion.

5. The leaflet fixation device of claim 3, wherein the tissue retention features comprise barbs, hooks, teeth, spikes, or a combination thereof.

6. The leaflet fixation device of claim 4, wherein at least one tissue retention feature comprises a feature that promotes tissue ingrowth into the unitary elongated body.

7. The leaflet fixation device of any one of claims 1 to 2, wherein each arm of the plurality of arms is configured to move independently of the other arms of the plurality of arms.

8. The leaflet fixation device of any one of claims 1 to 2, wherein the weight of the leaflet fixation device is between 50 and 150 mg.

9. The leaflet fixation device of any one of claims 1 to 2, wherein the proximal neck is divided into a plurality of necks, and wherein the integral elongated body comprises an offset configuration in which at least one arm is proximate to at least one neck.

10. The leaflet fixing device according to any one of claims 1 to 2, which is used as part of a valve repair system, the valve repair system comprising: A delivery tool comprising an expansion mechanism for each arm, the expansion mechanism being configured to independently transition the arms between the closed configuration and the open configuration, wherein the expansion mechanism comprises: a jaw pivotally coupled to a distal end of the delivery tool, the jaw including a coupler configured to releasably couple the arm to the jaw; and wherein rotation of the jaws in a first direction pulls the arms of the leaflet fixation device away from the proximal neck of the leaflet fixation device to an open configuration to provide space for valve tissue therebetween; and wherein rotation of the jaws in a second direction restores the arms to the closed configuration.

11. The leaflet fixing device according to any one of claims 1 to 2, which is used as part of a valve repair system, the valve repair system comprising: A delivery tool comprising an expansion mechanism for each arm, the expansion mechanism being configured to independently transition the arms between the closed configuration and the open configuration, wherein each expansion mechanism comprises: an expansion arm rotatably coupled to a distal end of the delivery tool, the expansion arm being arranged to, when rotated in a first direction, push the arm of the leaflet fixation device away from the proximal neck of the leaflet fixation device to the open configuration to provide space for valve tissue therebetween; wherein rotation of the expansion arm in a second direction returns the arm to the closed configuration.

12. The leaflet fixation device of any one of claims 1 to 2, as part of a valve repair system, wherein the proximal neck, the distal arms, or both of the leaflet fixation device comprise a tissue retention feature configured to pierce but not penetrate tissue, penetrate tissue, or both, and the valve repair system comprises: A delivery tool comprising an expansion mechanism for each arm, the expansion mechanism being configured to independently transition the arms between the closed configuration and the open configuration, the expansion mechanism being configured to prevent engagement between the first tissue engagement surface and the second tissue engagement surface and tissue during placement of the leaflet fixation device.

13. A valve repair system comprising A leaflet fixing device comprising a unitary elongated body comprising a proximal neck comprising a first tissue engaging surface and a distal portion comprising an arm having a second tissue engaging surface, the arm comprising an open configuration wherein the first tissue engaging surface is spaced away from the second tissue engaging surface, the arms are biased toward a closed configuration wherein the second tissue engaging surface is held proximate to the first tissue engaging surface by a biasing force; and a delivery tool comprising an expansion mechanism for each arm, the expansion mechanism being configured to independently transition the arms between the closed configuration and the open configuration, wherein the arm is one of a plurality of arms biased toward the closed configuration, and wherein in the closed configuration, each arm of the unitary elongated body is proximate a different portion of the proximal neck of the unitary elongated body, and wherein the overall elongated body comprises a length and a width and the distal portion of the overall elongated body is separated along its width to define the plurality of arms, each of the plurality of arms having a common thickness; or wherein the overall elongated body comprises a length, a width and a thickness and the distal portion of the overall elongated body is separated along its thickness to define the plurality of arms, each of the plurality of arms having a common width.

14. A valve repair system according to claim 13, wherein the proximal neck of the integrally slender body, the distal portion of the integrally slender body, or both include a tissue retention feature, which is configured to pierce but not penetrate tissue, penetrate tissue, or both, and the tissue retention feature includes a barb, a hook, a tooth, a spike, a hole, a texture, or a combination thereof.

15. The valve repair system according to claim 13, wherein the expansion mechanism comprises: a jaw pivotally coupled to a distal end of the delivery tool, the jaw including a coupler configured to releasably couple the arm to the jaw, wherein rotation of the jaws in a first direction pulls the arms of the leaflet fixation device away from the proximal neck of the leaflet fixation device to the open configuration to provide space for valve tissue therebetween, and wherein rotation of the jaws in a second direction returns the arms to the closed configuration.

16. The valve repair system according to claim 13, wherein each expansion mechanism comprises: an expansion arm rotatably coupled to a distal end of the delivery tool, the expansion arm being arranged to, when rotated in a first direction, push the arm of the leaflet fixation device away from the proximal neck of the leaflet fixation device to the open configuration to provide space for valve tissue therebetween; wherein rotation of the expansion arm in a second direction returns the arm to the closed configuration.

17. A valve repair system according to claim 13, wherein the proximal neck, the distal arm, or both of the leaflet fixation device include a tissue retention feature that is configured to pierce but not penetrate tissue, penetrate tissue, or both, and the expansion mechanism is configured to enable the arms to independently transition between the closed configuration and the open configuration, and the expansion mechanism is configured to prevent engagement between the first tissue engaging surface and the second tissue engaging surface and tissue during placement of the leaflet fixation device.

Images