Patent Publication Number: US-2021186698-A1

Title: Wide clip with deformable width

Description:
FIELD OF DISCLOSED SUBJECT MATTER 
     The disclosed subject matter is directed to medical devices for the endovascular, percutaneous or minimally invasive surgical treatment of bodily tissues, such as tissue approximation or valve repair. More particularly, the present disclosure relates to repair of valves of the heart and venous valves. 
     Surgical repair of bodily tissues can involve tissue approximation and fastening of such tissues in the approximated arrangement. When repairing valves, tissue approximation includes coapting the leaflets of the valves in a therapeutic arrangement which can then be maintained by fastening or fixing the leaflets. Such coaptation can be used to treat regurgitation, which commonly occurs in the mitral valve and in the tricuspid valve. 
     Mitral valve regurgitation is characterized by retrograde flow from the left ventricle of a heart through an incompetent mitral valve into the left atrium. During a normal cycle of heart contraction (systole), the mitral valve acts as a check valve to prevent flow of oxygenated blood back into the left atrium. In this way, the oxygenated blood is pumped into the aorta through the aortic valve. Regurgitation of the mitral valve can significantly decrease the pumping efficiency of the heart, placing the patient at risk of severe, progressive heart failure. 
     Mitral valve regurgitation can result from a number of different mechanical defects in the mitral valve or the left ventricular wall. The valve leaflets, the valve chordae which connect the leaflets to the papillary muscles, the papillary muscles or the left ventricular wall can be damaged or otherwise dysfunctional. Commonly, the valve annulus can be damaged, dilated, or weakened limiting the ability of the mitral valve to close adequately against the high pressures of the left ventricle. 
     DESCRIPTION OF RELATED ART 
     Treatments for mitral valve regurgitation rely on valve replacement or repair including leaflet and annulus remodeling, the latter generally referred to as valve annuloplasty. Another technique for mitral valve repair, which relies on suturing adjacent segments of the opposed valve leaflets together is referred to as the “bow-tie” or “edge-to-edge” technique. Preferably, the use of devices and systems should not require open chest access and, rather, be capable of being performed either endovascularly, i.e., using devices, such as a catheter, which are advanced to the heart from a point in the patient&#39;s vasculature remote from the heart. Furthermore, such devices and systems should allow for repositioning and optional removal of a fixation device (i.e., valve repair clip) prior to fixation to ensure optimal placement. Such devices and systems likewise can be useful for repair of tissues in the body other than heart valves. 
     SUMMARY 
     The purpose and advantages of the disclosed subject matter will be set forth in and apparent from the description that follows, as well as will be learned by practice of the disclosed subject matter. Additional advantages of the disclosed subject matter will be realized and attained by the methods and systems particularly pointed out in the written description and claims hereof, as well as from the appended drawings. 
     To achieve these and other advantages and in accordance with the purpose of the disclosed subject matter, as embodied and broadly described, the disclosed subject matter is directed to a fixation device for treating a patient. 
     In accordance with the disclosed subject matter, a fixation device for fixation of leaflets of a heart valve includes a central assembly and at least one arm moveably coupled relative to the central assembly. The at least one arm includes a deformable frame having a first end and a second end and a longitudinal axis defined therebetween, the second end being moveable between a closed position and an open position. The deformable frame further includes first and second deformable flex portions, each flex portion extending along a respective lateral side of the deformable frame and having a deformed condition and an undeformed condition, and each flex portion having an outer lateral edge. The at least one arm has a maximum deformed arm lateral cross-dimension with the flex portions in the deformed condition and a maximum undeformed arm width defined between the outer lateral edge of the first flex portion and the outer lateral edge of the second flex portion in the undeformed condition. The ratio of the maximum deformed arm lateral cross-dimension to the maximum undeformed arm width is at least 1:1.3. The fixation device further includes at least one gripping element moveable relative to the at least one arm to capture a native leaflet therebetween. 
     In accordance with the disclosed subject matter, the deformable frame can further include a trough defined along the longitudinal axis, and further the first flex portion can include a deformable first wing extension extending laterally from a first lateral side of the trough and the second flex portion includes a deformable second wing extension extending laterally from a second lateral side of the trough. The first and second wing extensions each can have a second end edge extending laterally from the second end of the deformable frame at a second end angle defined between the second end edge and the longitudinal axis, wherein the second end angle is between 15 and 45 degrees. The deformable frame, including the trough and the first and second wing extensions, can be a single piece construction. Additionally, the first and second wing extensions can each include at least one notch defined along a respective lateral edge thereof. Additionally or alternatively, the first and second wing extensions can each comprise an open wing extension frame defining a wing opening therethrough in plan view. The maximum undeformed arm width can be proximate the second end of the deformable frame. 
     Furthermore, with the trough defined along the longitudinal axis, the trough can have a greater width between opposing lateral sides of the trough along a length of the arm proximate the maximum undeformed arm width. In this manner, at least one gripping element can have a first end coupled to a portion of the fixation device and a second end moveable relative to the at least one arm, wherein the gripping element can have a greater width proximate the second end of the gripping element. The first and second wing extensions can be made of shape memory material. 
     In accordance with another aspect of the disclosed subject matter, the first flex portion can comprise a deformable first flank member extending longitudinally along a first lateral side of the deformable frame and the second flex portion can comprise a deformable second flank member extending longitudinally along a second lateral side of the deformable frame, the first and second flank members in the deformed condition being aligned generally parallel with longitudinal axis. The first and second flank members in the undeformed condition can each have at least a length thereof extending outwardly away from the longitudinal axis. 
     The deformable frame can further include a first strut extending laterally from the first flank member to the second flank member, wherein the first strut comprises a hinge portion having a compressed configuration with the deformable frame in the deformed condition and an extended configuration with the deformable frame in the undeformed condition. The hinge portion can be biased toward the extended condition. The deformable frame can further comprise an end strut extending laterally from the first flank member to the second flank member at the second end of the deformable frame. The end strut can include a hinge portion having a compressed configuration with the deformable frame in the deformed condition and an extended configuration with the deformable frame in the undeformed condition, the first strut can be spaced longitudinally from the end strut. 
     Alternatively, the deformable frame can include a first strut extending laterally from the first flank member toward the second flank member and a second strut extending laterally from the second flank member toward the first strut member. The deformable frame can further comprise an end strut extending laterally from the first flank member to the second flank member at the second end of the deformable frame. The end strut can comprise a hinge portion having a compressed configuration with the deformable frame in the deformed condition and an extended configuration with the deformable frame in the undeformed condition. The first and second struts can be in overlapping sliding arrangement for movement relative each other between the deformed condition and the undeformed condition. Alternatively, the first and second struts can be laterally spaced from each other with the deformable frame in the undeformed condition. The fixation device can further include a middle support member extending parallel with the longitudinal axis between the first and second flank members. 
     As also embodied herein, the deformable frame can include a plurality of first struts extending laterally from the first flank member toward the second flank member and a plurality of second struts extending laterally from the second flank member toward the first strut member. The plurality of first struts and the plurality of second struts can be configured to interlock with each other in the deformed condition and release from each other in the undeformed condition. The first and second flank members can each have a tapered portion proximate the second end of the deformable frame. Additionally or alternatively, the at least one arm can comprise an expandable mesh portion extending between the first and second flank members. The first and second flank members can comprise shape memory material. 
     In accordance with another aspect of the disclosed subject matter, a system for fixation of leaflets of a heart valve includes a guide catheter having an inner diameter, and a fixation device for fixation of leaflets of a heart valve. The device including a central assembly and at least one arm moveably coupled relative to the central assembly. The at least one arm includes a deformable frame having a first end and a second end and a longitudinal axis defined therebetween. The second end is moveable between a closed position and an open position. The deformable frame further includes first and second deformable flex portions. Each flex portion extends along a respective lateral side of the deformable frame and has a deformed condition and an undeformed condition. Each flex portion has a lateral outer edge. The at least one arm has a maximum deformed arm lateral cross-dimension with the flex portions in the deformed condition and a maximum undeformed arm width defined between the outer lateral edge of the first flex portion and the outer lateral edge of the second flex portion in the undeformed condition. The ratio of the maximum deformed arm lateral cross-dimension to the maximum undeformed arm width is at least 1:1.3. The fixation device further includes at least one gripping element moveable relative to the at least one arm to capture a native leaflet therebetween. 
     The maximum deformed arm lateral cross-dimension can be less than the inner diameter of the guide catheter, and the maximum undeformed arm width can be greater than the inner diameter of the guide catheter. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         FIG. 1  is a perspective view of an exemplary embodiment of a fixation device for use in accordance with the disclosed subject matter. 
         FIG. 2A  is a front view of the fixation device of  FIG. 1 , wherein optional arms of greater length are depicted with dashed lines. 
         FIGS. 2B-2D  are front views of the fixation device of  FIG. 1  at various positions, wherein optional arms of greater length are depicted with dashed lines. 
         FIG. 3A  is a front schematic view of the fixation device of  FIG. 1  having leaflets captured therein. 
         FIG. 3B  is a side view of the fixation device of  FIG. 1  to schematically depict a contact patch area. 
         FIG. 4  is a plan view of an exemplary embodiment of a deformable frame of an arm in an undeformed condition in accordance with the disclosed subject matter. 
         FIG. 5  is a front cross-section view of a portion of the fixation device of  FIG. 1  aligned with a plan view of a corresponding deformable frame of the arm of the disclosed subject matter. 
         FIGS. 6A-6C  are side views of a portion of the fixation device of  FIG. 1 , each with an alternative embodiment of the deformable frame of an arm in an undeformed condition in accordance with the disclosed subject matter. 
         FIGS. 7A-7B  are a perspective views of different embodiments of the deformable frames of arms in an undeformed condition in accordance with the disclosed subject matter. 
         FIG. 8  is a side view of a portion of the fixation device of  FIG. 1 , with an exemplary embodiment of the deformable frame of the arm in an undeformed condition in accordance with the disclosed subject matter. 
         FIG. 9  is a schematic plan view of an alternative embodiment of a deformable frame of an arm in a deformed condition in accordance with the disclosed subject matter. 
         FIG. 10  is a side view of a portion of the fixation device of the  FIG. 1 , with an alternative embodiment of the deformable frame of the arm in an undeformed condition in accordance with the disclosed subject matter. 
         FIG. 11  is a perspective view of  FIG. 10  including the alternative embodiment of the deformable frame of the arm. 
         FIG. 12  is a side view of a portion of the fixation device of  FIG. 1 , with another exemplary embodiment of a deformable frame of an arm in an undeformed condition and a gripping element of the disclosed subject matter. 
         FIG. 13  is a perspective view of an exemplary embodiment of a distal end of a system for delivering the fixation device of  FIG. 1 . 
         FIG. 14  is a perspective view of the distal end of the guide catheter in accordance with the delivery system of  FIG. 13 . 
         FIGS. 15A-15B  are perspective views of an exemplary embodiment of a deformable frame of an arm in a deformed condition and an undeformed condition, respectively, in accordance with the disclosed subject matter. 
         FIGS. 16A-16B  are plan views of another embodiment of a deformable frame of an arm in a deformed condition and an undeformed condition, respectively, in accordance with the disclosed subject matter. 
         FIG. 17  is a side view of a portion of the fixation device of the  FIG. 1 , with an exemplary embodiment of another embodiment of deformable frame of an arm in an undeformed condition in accordance with the disclosed subject matter. 
         FIGS. 18A-18B  are perspective views of an alternative embodiment of deformable frame of an arm in a deformed condition and an undeformed condition, respectively, in accordance with the disclosed subject matter. 
         FIG. 18C  is a cross-sectional end view of two of the alternative embodiments of the deformable frame of the arm of  FIGS. 18A-18B , in accordance with the disclosed subject matter. 
         FIGS. 19A-19B  are perspective views of another embodiment of a deformable frame of an arm in a deformed condition and an undeformed condition, respectively, in accordance with the disclosed subject matter. 
         FIG. 20  is a schematic top view of an alternative embodiment of the fixation device of  FIG. 1  having boss features. 
     
    
    
     DETAILED DESCRIPTION 
     Reference will now be made in detail to the various exemplary embodiments of the disclosed subject matter, exemplary embodiments of which are illustrated in the accompanying drawings. 
     The fixation device for use with the disclosed subject matter provides an edge-to-edge transcatheter valve repair option for patients having various conditions, including regurgitant mitral valves or tricuspid valves. Transcatheter (e.g., trans-septal) edge-to-edge valve repair has been established using a fixation device, such as the MitraClip Transcatheter Mitral Valve Repair device. These fixation devices generally are configured to capture and secure opposing native leaflets using two types of leaflet contacting elements. The first element is a sub-valvular arm (also known as a distal element or fixation element) to contact the ventricular side of a native leaflet to be grasped. With the arm positioned underneath to stabilize the native leaflet in a beating heart, a second gripping element (e.g., a proximal element) can be lowered or moved toward the arm and into contact with the atrial side of the native leaflet to capture the leaflet therebetween. Once each native leaflet is captured by a respective arm and gripping element, the fixation device can be closed by raising or moving the arms toward a center of the fixation device such that the leaflets are brought into coaptation, which results in a reduction in valvular regurgitation during ventricular systole. Furthermore, a covering can be provided on the arms and/or gripping elements to facilitate tissue ingrowth with the captured leaflets. 
     Additional details of exemplary fixation devices in accordance with the disclosed subject matter are set forth below. Furthermore, a number of patents and publications disclose additional details and aspects of such fixation devices and related operations. See for example, U.S. Pat. No. 7,226,467 to Lucatero et al.; U.S. Pat. No. 7,563,267 to Goldfarb et al.; U.S. Pat. No. 7,655,015 to Goldfarb et al.; U.S. Pat. No. 7,736,388 to Goldfarb et al.; U.S. Pat. No. 7,811,296 to Goldfarb et al.; U.S. Pat. No. 8,057,493 to Goldfarb et al.; U.S. Pat. No. 8,303,608 to Goldfarb et al.; U.S. Pat. No. 8,500,761 to Goldfarb et al.; U.S. Pat. No. 8,734,505 to Goldfarb et al.; U.S. Pat. No. 8,740,920 to Goldfarb et al.; U.S. Pat. No. 9,510,829 to Goldfarb et al.; U.S. Pat. No. 7,635,329 to Goldfarb et al.; U.S. Patent Application Publication No. 2017/0042546 to Goldfarb et al.; U.S. Patent Application Publication No. 2017/0239048 to Goldfarb et al.; U.S. Patent Application Publication No. 2018/0325671 to Abunassar et al., the entirety of the contents of each of these patents and published applications is incorporated herein by reference. 
     In grasping tissue and leaflet capture for mitral valve disease, certain patient conditions and anatomies, such as those associated with larger dynamic gaps between leaflet tips, can create challenges for capture. As such, there is an opportunity for a fixation device capable of bridging larger gaps, such as in functional mitral regurgitation (FMR), while also providing more reliable leaflet capture, for example in cases of dynamic, chaotic, or overly severe degenerative mitral regurgitation (DMR), such as in cases of Barlow&#39;s Syndrome. Particularly, the size and configuration of the arm of the fixation device can significantly improve performance. However, such modifications can be configured to account for numerous factors to produce desired clinical benefit and still be deliverable transvascularly through a guide catheter. For example, a typical guide catheter size for delivery can have an inner diameter of about 0.22 inch or less. Furthermore, when positioned within a patient, the guide catheter defines a tortious path through which the fixation device can be delivered. As such, the fixation device can be configured to be capable of such delivery through the corresponding bends and turns of the guide catheter. 
     Additionally, and as previously noted, the fixation device can be configured to capture or grasp a leaflet between the arm and the gripping element. When in the closed position, it can facilitate further capture of adjacent leaflets positioned between two arms in the final implanted condition. Such capture can be a function of a contact patch area of the leaflets as defined by the width and configuration of the arms. Hence, increasing arm width along select lengths of the arm can increase contact patch area and corresponding capture. Additionally, arms can be configured with flexibility to increase deliverability through the guide catheter. In this manner, and in accordance with the disclosed subject matter, the arms can include a deformable frame creating a desired deformed lateral cross-dimension for delivery and a suitable undeformed width and configuration to provide a desired contact patch area. 
     Generally, and as set forth in greater detail below, the disclosed subject matter provided herein includes a fixation device for fixation of leaflets of a heart valve including a central assembly and at least one arm moveably coupled relative to the central assembly. The at least one arm includes a deformable frame having a first end and a second end and a longitudinal axis defined therebetween, the second end being moveable between a closed position and an open position. The deformable frame further includes first and second deformable flex portions, each flex portion extending along a respective lateral side of the deformable frame and having a deformed condition and an undeformed condition, and each flex portion having an outer lateral edge. The at least one arm has a maximum deformed arm lateral cross-dimension with the flex portions in the deformed condition and a maximum undeformed arm width defined between the outer lateral edge of the first flex portion and the outer lateral edge of the second flex portion in the undeformed condition. The ratio of the maximum deformed arm lateral cross-dimension to the maximum undeformed arm width is at least 1:1.3. The fixation device further includes at least one gripping element moveable relative to the at least one arm to capture a native leaflet therebetween. 
     Referring to  FIGS. 1-2A  for the purpose of illustration and not limitation, a fixation device  104  for fixation of native leaflets of a heart valve is disclosed herein. The fixation device as embodied herein includes a central assembly  171 . The central assembly  171  can include various central components for operation and release of the fixation device, for example, a coupling member  174  as described further in the disclosures of the patents and applications incorporated in their entirety by reference herein. The fixation device as depicted further includes at least one arm  108  moveably coupled relative to the central assembly  171 . As shown, the fixation device can further include a second arm  110  moveably coupled relative to the central assembly  171 . For purpose of understanding and reference only,  FIGS. 1, 2A-2D and 3A-3B  depict the arms without the flex portions of the disclosed subject matter. 
     With reference to  FIG. 2A , for illustration and not limitation, each arm  108 ,  110  can be rotatable or moved about a respective axis point  148 ,  150  between closed, open and inverted positions, as well as any position therebetween. Furthermore, the arms  108 ,  110  can be selected from a range of suitable lengths, wherein the appropriate length can be selected by the physician or health care provider after inspection of a patient. For purpose of comparison, a first length of each arm  108 ,  110  is depicted in  FIG. 2A  in solid lines, and a second longer length of each arm of the disclosed subject matter is depicted in dashed lines. Each arm depicted in solid lines can be an entirely separate arm with a different length as compared to the corresponding arm depicted in dashed lines. 
     As depicted herein in  FIGS. 2B-2D , various positions of the fixation device  104  are depicted for purpose of illustration and not limitation. Arms of longer length are illustrated in dashed lines for comparison to shorter arms. In  FIG. 2B , the fixation device is in the closed position, wherein the arms are positioned axially in alignment, e.g., vertically or nearly vertically as shown.  FIGS. 2C and 2D  illustrate the arms positioned with an angle A between each other. In  FIG. 2C , angle A is about 10 degrees and in  FIG. 2D  angle A is about 60 degrees. As disclosed herein, the fixation device is in the closed position when angle A is about 30 degrees or less, although another angle may result when leaflets of greater thickness are captured therebetween. Although not depicted, the arms can continue to open until angle A exceeds 180 degrees, e.g., inverted. 
     As previously noted generally, and as set forth in further detail below, a native leaflet can be captured between each arm and a respective gripping element. Each arm can then be moved toward its closed position. In this manner, adjacent leaflets can further be captured between two arms in the closed position. For example, and for illustration only,  FIGS. 3A-3B  show the fixation device  104  depicted with the arms  108 ,  110  at an angle A of about 20 to 30 degrees with two leaflets captured therebetween, wherein each leaflet is captured between an arm and a respective gripping element (wherein gripping element is not shown for clarity). As illustrated in  FIG. 3B , a contact patch  222  depicted in dashed lines is defined by the area of tissue contact between the arms. The contact patch area  222  represents a tissue-to-tissue contact patch area defined by the area of a leaflet in contact with a counterpart leaflet. As previously noted,  FIG. 3B  depicts a representative contact patch area when each arm does not include flex portions and the arms of the fixation device are at an angle A of about 20 to 30 degrees. The angle A can affect the contact patch area  222  wherein a reduced angle A can increase the contact patch area  222 , and likewise an increased angle A can decrease the contact patch area  222 . 
     In accordance with the disclosed subject matter, an arm configuration is provided with a deformable frame having deformable flex portions to increase contact patch area and capture of adjacent leaflets between two arms of the fixation device in a closed or final implanted position. Additionally, each arm can be configured to space the contact patch area from the first end of the arm, such as intermediate along the length of the arm or proximate the second end of the arm. Furthermore, the deformable frame has a deformed condition for delivery, and an undeformed condition for final implantation. A deformable frame of an arm can be made of shape memory material, e.g., Nitinol, or other sufficiently flexible material capable of being distorted when the deformable frame is in the deformed condition. 
     For purpose of illustration and not limitation, a plan view of an arm comprising a deformable frame for a fixation device in accordance with the disclosed subject matter is depicted in  FIG. 4 . Although  FIG. 4  and other figures throughout this application only depict a single arm for clarity, it is understood that the various features of the at least one arm  108  can apply similarly to one or more additional arms, such as, the second arm  110 . The at least one arm  108  is moveably coupled relative to the central assembly  171 . 
     As shown in  FIG. 4 , the arm  108  of the disclosed subject matter comprises a deformable frame  105  having a first end  140  and a second end  142  and a longitudinal axis  156  defined therebetween. The deformable frame  105  comprises first and second deformable flex portions  218 ,  220 . Each flex portion extends along a respective lateral side of the deformable frame  105  and has a deformed condition and an undeformed condition. Furthermore, each flex portion has an outer lateral edge  166 . The at least one arm  108  has a maximum undeformed arm width  164  defined between the outer lateral edge  166  of the first flex portion  218  and the outer lateral edge  166  of the second flex portion  220  in the undeformed condition. 
     As disclosed herein, the flex portions can be provided with a variety of configurations to facilitate the deformed conditions of the arms. Furthermore, the deformable frame  105  of the discussed subject matter further comprises a trough  145  defined along the longitudinal axis  156  to receive a gripping element  116  as described herein. For example, and as embodied herein, the first flex portion  218  can comprise a deformable first wing extension  162  extending laterally from a first lateral side of the trough  158  and the second flex portion  220  can comprise a deformable second wing extension  163  extending laterally from a second lateral side of the trough  159 . As depicted in  FIG. 4 , the first and second wing extension define a maximum undeformed arm width  164  between the outer lateral edges  166  of each wing extension  162 ,  163  in the undeformed condition. For purpose of delivery, each wing extension can be deformed such as by folding or curling each wing extension along the respective lateral side of the trough so as to substantially resemble the profile and configuration such as depicted in  FIG. 3B . In this manner, the arm  108  in the deformed condition defines a maximum deformed arm lateral cross-dimension  165  with the flex portions  218 ,  220  in the deformed condition, which, as embodied herein, is generally equal to the lateral cross-dimension between the opposing lateral sides of the trough  145 . For purpose and illustration and not limitation, the deformable frame  105 , including the trough  145  and the first and second wing extensions  162 ,  163 , can be a single piece construction. Further, the first and second wing extensions  162 ,  163  can be made of a variety of different materials, including, for example, a shape memory material as described further below. 
     As embodied herein, and with reference to  FIG. 4 , the first and second wing extensions  162 ,  163  can each have a first end edge  180  and a second end edge  182 , wherein the first end edge  180  can extend between a respective lateral side of the trough  158 ,  159  and an outer lateral edge  166 . As depicted, the first end edge  180  can be located closer to or proximate a first end  140  of the trough  145 . The second end edge  182  can extend between the respective lateral sides of the trough  158 ,  159  and the outer lateral edge  166 . The second end edge can  182  be located closer to or proximate the second end  142  of the trough. With further reference to  FIG. 4 , the first end edge  180  can have a first end fillet  192  at an intersection with the respective lateral side of the trough  158 ,  159 . Likewise, the second end edge  182  can have a second end fillet  194  at an intersection with the respective lateral side of the trough  158 ,  159 . Additionally, and as further depicted for illustration and not limitation, the first end edge  180  can have a first end round  196  at an intersection with the outer lateral edge  158 . Likewise, the second end edge  182  can have a second end round  198  at an intersection with the outer lateral edge  166 . The wing extensions depicted in  FIG. 4  are intended for purpose of illustration and not limitation, and wing extensions having various other configurations and dimensions are contemplated. 
     As previously noted, and in accordance with the disclosed subject matter, the fixation device  104  further includes at least one gripping element  116 , for example as shown in  FIG. 1 . The gripping element  116  can be moveable relative to the at least one arm  108  to capture a second native leaflet therebetween. In particular, the at least one gripping element  116  has a first end  228  coupled to a portion of the fixation device and a second end  230  moveable relative to the at least one arm  108 . In accordance with the disclosed subject matter, each arm can be configured to define or have a trough  145  aligned along the longitudinal axis  156 . The trough can be configured to receive the gripping element  116  therein. 
     As embodied herein, each gripping element includes a plurality of friction elements  152 , such as in rows. For example, each gripping element  116 ,  118  can have at least four rows of friction elements  152 . The friction elements  152  can allow for improved tissue engagement during leaflet capture. If the fixation device requires adjustment after an initial leaflet capture, the arms can be opened, the gripping element can be raised vertically, and tissue can disengage from the fixation device, facilitating re-grasp and capture. 
     For example, and with reference again to  FIG. 1 , and as further embodied herein, each gripping element  116 ,  118  can be biased toward each respective arm  108 ,  110 . Prior to leaflet capture, each gripping element  116 ,  118  can be moved inwardly toward a longitudinal center of the device (i.e., away from each respective arm  108 ,  110 ) and held with the aid of one or more gripping element lines (not shown) which can be in the form of sutures, wires, rods, cables, polymeric lines, or other suitable structures. The gripping line elements can be operatively connected with the gripping elements  116 ,  118  in a variety of ways, such as by being threaded through loops (not shown) disposed on the gripping elements  116 ,  118 . 
     As previously noted, and as shown in  FIG. 5 , the at least one gripping element  116  can have a plurality of friction elements  152  along the length thereof. In accordance with another aspect of the disclosed subject matter, the arm and respective gripping element can be aligned such that when the at least one gripping element  116  is received within the trough of the at least one arm  108 , the plurality of friction elements  152  are disposed along a length defined between the intersection of the first end edge  180  and the respective lateral sides of the trough  158 ,  159  at one end, and the intersection of the second end edge  182  and the respective sides of the trough  158 ,  159  of the respective wing extensions at the other end. Such a configuration can further increase the leaflet tissue securement at the region of flex portions, e.g., the wing extensions. In the configuration embodied herein, frictional elements positioned at the first and second ends of each wing extension can reduce or eliminate tissue erosion by more secure engagement at the desired locations. 
     The size, shape and construction of the arm of the discussed subject matter can be varied or selected as desired to accommodate performance criteria. For example, and not by limitation, various frames of alternative arm configurations having flex portions comprising wing extensions in accordance with the discussed subject matter are disclosed herein. The configuration of the frame  105  can be selected to provide the desired performance of each arm (e.g., to capture and retain a leaflet, to track through and retract into a guide catheter, etc.). For example, as compared to the configuration of the wing extensions in  FIG. 4 , the first and second wing extensions  162 ,  163  disclosed in  FIGS. 6A-6C  each further includes at least one notch  222  defined along a respective lateral edge thereof to increase flexibility of the wing extensions. As depicted herein, wing extensions having a notch can include first and second end rounds  194 ,  198  that extend from the first and second end edges  180 ,  182 , respectively, until the outer lateral edge  166  extends towards the longitudinal axis of the arm. As depicted in  FIGS. 6A and 6C , the notch  222  can extend up to or into the trough  145 . Alternatively, and as depicted in  FIG. 6B , the notch  222  can terminate prior to the trough  145 . Further, the various of the wing extensions can vary, as depicted, for example, wherein the first and second end rounds are relatively large in FIGS,  6 B and  6 C, and, by comparison, relatively small in  FIG. 6A . The undeformed arm width at the innermost point of the notch (i.e., the deepest point of the notch) can be between about 25% and 50% less than the maximum undeformed arm width  164 . For example, the maximum undeformed arm width  164  can be about 0.20 inch and the undeformed arm width at the innermost point of the notch can be between about 0.010 inch and 0.15 inch. Likewise, the maximum undeformed arm width  164  can be about 0.40 inch and the undeformed arm width at the innermost point of the notch can be between about 0.020 inch and 0.25 inch. 
     Referring to  FIGS. 7A-7B , alternative embodiments of wing extension are disclosed, wherein the first and second wing extensions  162 ,  163  each comprises an open wing extension frame  224  defining a wing opening  226  therethrough in plan view. Although not shown, each wing extension embodiment disclosed herein can alternative be configured as an open wing extension frame. In this manner, and in accordance with the disclosed subject matter, the open wing extension frame  224  can further increase the compressibility of the deformable frame  105 . 
     As further embodied herein in  FIG. 8 , an alternative arm configuration, referenced as a duck bill arm configuration, is disclosed for purpose of illustration and not limitation. In the duck bill arm configuration, first and second wing extensions  162 ,  163  each has a second end edge  182  extending laterally from the second end of the deformable frame  142  at a second end angle  186  defined between the second end edge  182  and the longitudinal axis  156 . The second end angle  186  can be between 15 and 45 degrees. When undeformed and implanted, the second end angle forms a taper that that reduces undesirable focal stresses that may occur under various circumstances, e.g., with certain squared clip arms. Additionally, and as further embodied herein in  FIG. 8 , the maximum undeformed arm width  164  and corresponding contact patch area can be proximate the second end  142  of the deformable frame. For purpose of delivery, each wing extension  162 ,  163  can be deformed such as by folding or curling each wing extension along the opposing lateral sides  158 ,  159  of trough  145  so as to substantially resemble the profile and configuration such as depicted in  FIG. 3B . In this manner, the deformable frame  105  of the arm in the deformed condition defines a maximum deformed arm lateral cross-dimension  165  with the flex portions  218 ,  220  in the deformed condition, which, as embodied herein, is generally equal to the lateral cross-dimension between the opposing lateral sides  158 ,  159  of the trough  145 . 
     In accordance with another aspect of the disclosed subject matter, and with reference to  FIG. 9  for purpose of illustration and not limitation, the first flex portion can include a deformable first flank member extending longitudinally along a first lateral side of the deformable frame. Likewise, the second flex portion can include a deformable second flank member extending longitudinally along a second lateral side of the deformable frame. The first and second flank members in the deformed condition can be aligned generally parallel with the longitudinal axis. 
     For example, and as embodied herein, the first flex portion  218  can comprise a deformable first flank member  232  extending longitudinally along a first lateral side of the deformable frame  262  and the second flex portion  220  can comprise a deformable second flank member  234  extending longitudinally along a second lateral side of the deformable frame  264 . As shown in  FIG. 9 , the first and second flank members  232 ,  234  in the deformed condition being aligned generally parallel with longitudinal axis  156 . As shown, for purpose of illustration and not limitation, the deformable frame  105  can include a first strut  236  extending laterally from the first flank member  232  to the second flank member  234 . The first strut  236  can comprise a hinge portion  240  having a compressed configuration with the deformable frame  105  in the deformed condition, as shown for example in  FIG. 9 . 
     Additionally, and as further illustrated herein, the deformable frame  105  can comprise an end strut  242  extending laterally from the first flank member  232  to the second flank member  234  at the second end of the deformable frame  105 . The end strut  242  can comprise a hinge portion  240  having a compressed configuration with the deformable frame  105  in the deformed condition and an extended configuration with the deformable frame  105  in the undeformed condition. As embodied herein, the first strut  236  can be spaced longitudinally from the end strut  242 . To enable movement between the deformed and unformed conditions, the deformable frame, including the first and second flank members  232 ,  234  and struts  236 ,  242 , can comprise shape memory material and bias toward the undeformed condition, and/or heat treated to expand toward the undeformed condition when a predetermined temperature is reached or exceeded. Although not shown, additional variations are contemplated, such as a deformable frame  105  having an end strut  242  and a hinge portion  240 , wherein no additional strut (e.g., first strut  236 ) is included. 
     In accordance with a further aspect of the disclosed subject matter, and with continued reference to  FIG. 9  and further reference to  FIG. 20 , the fixation device  104  can include a first boss  258  (depicted schematically) corresponding to the first arm  108  and a second boss  260  corresponding to the second arm  110 . Each of the first and second boss  258 ,  260  can have a tapered or curved geometry (e.g., a hemispherical shape). As embodied herein, for illustration and not limitation, the boss  258 ,  260  can be secured to the coupling member  174 . As the arm  108 ,  110  moves towards the closed the position, the boss  258 ,  260  can be configured to engage and urge the first and second flank members  232 ,  234  outwardly towards the undeformed condition of the arm  108 ,  110 . The boss  258 ,  260  can be disposed proximate the first end  140  of the arm and below tissue contact patch area  222  such that the boss can directly contact the flank members  232 ,  234 . Alternatively, the boss  158 ,  160  can be disposed within the contact patch area  222  such that the boss  258 ,  260  is configured to engage the flank members  232 ,  234  with native leaflet tissue therebetween. Additional details of the boss  258 ,  260  are discussed below in  FIG. 20 . 
     Referring to  FIGS. 10-11 , the deformable frame  105  of the at least one arm  108 , as previously shown schematically in  FIG. 9  in the compressed or deformed condition for delivery, is now depicted in the expanded or released condition for implantation. As shown, the first strut  236  and the end strut  242  have an extended configuration with the deformable frame  105  of the arm  108  in the undeformed condition forming the maximum undeformed arm width  164 . As embodied herein, the hinge portion  240  can be biased toward the extended condition. Additionally or alternatively, the flank members  232 ,  234  can be biased outwardly to the expanded or released condition. 
     Although each of the embodiments of the  FIGS. 4-8  depict an arm of the disclosed subject matter having a trough  145  of generally uniform width, it is understood alternative configurations can be provided. For example, and with continued reference to  FIGS. 10 and 11 , the arm of the disclosed subject matter can be provided with a trough  145  having a varied width along a length of the arm  108 . In this manner, and in accordance with another aspect of the disclosed subject matter, the deformable frame  105  can include a trough  145  having a greater width between opposing lateral sides of the trough  158 ,  159  along a length of the arm  108  proximate the maximum undeformed arm width  164 . With reference to the example embodiment of  FIGS. 10-11 , the maximum undeformed arm width  164  can be disposed proximate the second end  142  of the deformable frame  105 , such as by providing wing extensions  218 ,  220  disposed proximate the second end  142 . The trough  145  can be provided with an increasing width between lateral sides of the trough aligned accordingly. As such, the trough  145  in the undeformed condition can have width sized to receive the at least one gripping element  116  as depicted in  FIGS. 10-11 . With reference to  FIG. 12 , the gripping element, if made of suitable material, likewise can increase in width to correspond to the increasing width of the trough  145 . That is, and as depicted in  FIG. 12 , the gripping element  116  can have a greater width proximate the second end  230  of the gripping element  116 . The fixation device can further comprise a second gripping element  118  of similar configuration moveable relative to the second arm  110  to capture a native leaflet therebetween. Furthermore, if desired, although not shown, the second end edge of the wing extension  182  can be angled similar to the duck bill embodiment of  FIG. 8 . 
     Referring now to  FIGS. 13-14 , a system for fixation of leaflets of a heart valve includes the fixation device  104  of the disclosed subject matter capable of delivery through a guide catheter  254  having an inner diameter  256 , as shown for purpose of the illustration and not limitation. To facilitate delivery of the fixation device, the maximum deformed arm lateral cross-dimension  165  can be less than the inner diameter  256  of the guide catheter  254 . To increase the contact patch area, as discussed above, the maximum undeformed arm width  164  thus can be greater than the inner diameter  256  of the guide catheter  254 . That is the deformable frame  105  has a maximum deformed arm lateral cross-dimension  165  when the flex portions  218 ,  220  are in the deformed condition. Furthermore, the ratio of the maximum deformed arm lateral cross-dimension  165  to the maximum undeformed arm width  164 , as discussed above, is at least 1:1.3, such as at least 1:1.5. For example, for a 16 French guide catheter, when the deformable frame  105  of the arm  108  depicted herein is delivered through the guide catheter, a maximum deformed arm lateral cross-dimension  164  can be between about 0.135 inch and 0.210 inch, such as a maximum deformed arm lateral cross-dimension  165  of about 0.203 inch. Each arm can have a variety of configurations to transition the arm from the deformed condition to the undeformed condition, such as, but not limited to, the various configurations disclosed herein. 
     With reference now to  FIGS. 15-19 , a variety of alternative configurations of the deformable frame having first and second flex portions comprising respective first and second flank members  232 ,  234  are also provided for purpose of illustration and not limitation. For example, in each of these embodiments, among others, the first flex portion  218  can comprise a deformable first flank member  232  extending longitudinally along a first lateral side of the deformable frame  105  and the second flex portion  220  can comprise a deformable second flank member  234  extending longitudinally along a second lateral side of the deformable frame  105 . The first and second flank members  232 ,  234  in the deformed condition can be aligned generally parallel with longitudinal axis  156 . As further embodied herein, the first and second flank members  232 ,  234  in the undeformed condition each can have at least a length thereof extending outwardly away from the longitudinal axis  156 . See, for example,  FIGS. 15B, 18B, 19B, and 20B . 
     With reference now to the exemplary embodiment of  FIGS. 15A-15B , the deformable frame  105  of the arm  108  includes a plurality of struts  235  extending laterally from the first flank member  232  to the second flank member  234 . Each strut  235  includes a hinge portion  240  having a compressed configuration with the deformable frame  105  of the arm  108  in the deformed condition and an extended configuration with the deformable frame  105  of the arm  108  in the undeformed condition. For example, and as illustrated herein, each strut  235  has a generally V-shape in the deformed condition and a generally linear shape in the undeformed condition. As depicted herein in  FIG. 15B , the V-shape struts  235  can be planar when the flank members extend outwardly. Struts having various other shapes are also contemplated. Further, the struts can be configured with a spring bias towards an expanded configuration, and/or configured to be manually activated towards the expanded configuration. 
     Further in accordance with the disclosed subject matter, and with reference to the embodiments disclosed in  FIGS. 16A-16B , for purpose of illustration and not limitation, the deformable frame  105  can include a first strut  236  extending laterally from the first flank member  232  toward the second flank member  234  and a second strut  238  extending laterally from the second flank member  234  toward the first strut  236  member. As embodied herein, the first and second struts  236 ,  238  can be in an overlapping sliding arrangement for movement relative each other between the deformed condition and the undeformed condition. In this manner, the overlapping struts can provide structural stability along an intermediate section of the frame, yet still allow lateral expansion from the undeformed condition to the deformed condition. Additionally, and as previously discussed, the deformable frame  105  of the arm  108  embodied in  FIGS. 16A-16B  can further comprise an end strut  242  extending laterally from the first flank member  232  to the second flank member  234  at the second end of the deformable frame  105 . Further, the end strut  242  disclosed herein includes a hinge portion  240  having a compressed configuration with the deformable frame  105  in the deformed condition, as shown in  FIG. 16B , and an extended configuration with the deformable frame  105  in the undeformed condition, as shown in  FIG. 16A . 
     Alternatively, and as depicted in  FIG. 17 , the first and second struts  236 ,  238  can be laterally spaced from each other with the deformable frame  105  in the undeformed condition. Furthermore, and in lieu of a hinge, first and second struts  236 ,  238  can be configured to overlap at least in the deformed condition, not shown. As illustrated in  FIG. 17 , the arm  108  can include a middle support member  244  extending generally parallel with the longitudinal axis  156  between the first and second flank members  232 ,  234 . Moreover, the first and second flank members  232 ,  234  each can have a tapered portion  246  proximate the second end of the deformable frame  105  for further strength and stability, as well to reduce undesirable focal stresses that may occur under various circumstances, e.g., with squared ends. Such a taper can likewise be produced with alternative frame configurations. 
     In accordance with yet another embodiment of the disclosed subject matter having first and second flank members, and as illustrated in  FIGS. 18A-18C , the deformable frame  105  of the arm  108  can comprise a plurality of first struts  236  extending laterally from the first flank member  232  toward the second flank member  234  and a plurality of second struts  238  extending laterally from the second flank member  234  toward the first strut  236  member. The plurality of first struts  236  and the plurality of second struts  238  can be configured to interlock with each other in the deformed condition, as depicted in  FIG. 18A , and release from each other in the undeformed condition, as depicted in  18 B. As with the embodiment of  FIGS. 15A-15B , the plurality of struts  236 ,  238  can be configured to remain generally planar with the flank members  232 ,  234  in the deformed condition. The plurality of struts  236 ,  238  can be configured to extend in the same longitudinal direction when in the deformed condition or inter-weave in and out of plane, as depicted in  FIG. 18C  when in the deformed configuration.  FIG. 18C  illustrates a cross-sectional end view of the first arm  108  and second arm  110  in the deformed condition. 
     With reference now to  FIGS. 19A-19B , the at least one arm  108  can additionally or alternatively comprise an expandable mesh portion  248  extending between the first and second flank members  232 ,  234 . The expandable mesh portion can  248  can be comprised of polymeric woven materials such as polyester, poly-lactic acid, PLGA, braided metals such as stainless steel, titanium alloys, cobalt chrome, or super-elastic metal alloys such as nitinol.  FIG. 19A  depicts the deformable frame  105  of the arm in the deformed condition, and  FIG. 19B  depicts the deformable frame  105  of the arm  108  in the undeformed condition. 
     As previously noted, the deformable frame  105  of arm  108  of the disclosed subject matter can be biased toward the undeformed condition for automatic expansion when released from a guide catheter, outer sheath, or the like. Additionally or alternatively, the deformable frame can be formed of a shape memory material, such as Nitinol, which is heat treated to deploy by temperature. Additionally or alternatively, and as previously noted with reference to  FIG. 9 , the at least one arm can be manually or selectively deployed from the deformed condition to the undeformed condition by a boss or cam or the like, wherein it is recognized that the “undeformed condition” references the condition in the which the deformable frame is held in position by the boss. For example, and with reference now to  FIGS. 20 , additional details of the boss  258 ,  260  are depicted for purpose of illustration and not limitation. The boss  258 ,  260  is previously noted with reference to  FIG. 9 . Here, in  FIG. 20  the boss  258 ,  260  is depicted in top view wherein the boss is configured to have a maximum width dimension at location  262 . The fixation device can be configured such that the arms  108 ,  110  are proximate the boss  258 ,  260  with the boss disposed between the flank members  232 ,  234 . As the arm is moved from a fully closed position toward an open position, the flank rides along the surface of the boss to expand toward an undeformed width. In this manner, the arm width can proportionally depend on the boss width such that the arms  108 ,  110  have a maximum undeformed arm width  164  when located proximate the maximum boss width location  262  (i.e., when the arm angle A is between about 15 to 45 degrees). Furthermore, when the arm angle is below about 10 degrees, the arm width approaches the maximum deformed arm lateral cross-dimension  165  to facilitate delivery of the device through a steerable guide catheter.  FIG. 20  depicts the first arm  108  at various arm angles A and widths W 1 -W 3 . At W 3 , the arm angle A is relatively large such that the flank members  232 ,  234  are outside the maximum boss width dimension location  162 . At W 2 , the arm angle is between 45 and 15 degrees and the flank members  232 ,  234  are located proximate the maximum boss width dimension location  162 . At W 1 , the arm angle is relatively small such that the flank members  232 ,  234  are inside the maximum boss width dimension location  162 . It is contemplated that the boss  258 ,  260  can also have a compressed configuration to further facilitate a reduced profile for the fixation device while in the delivery catheter. 
     For each embodiment disclosed herein, the fixation device can further include an assembly to move the arms between various defined positions, for example, and not limitation, and with reference to  FIG. 1 , the fixation device embodied herein includes two link members or legs  168 , each leg  168  having a first end which is rotatably joined with one of the arms  108 ,  110  and a second end which is rotatably joined with a base. The base  170  can be operatively connected with a stud  176  which can be operatively attached to a distal end of a delivery shaft (not shown for clarity). In some embodiments, the stud  176  can be threaded so that the distal end of a delivery shaft can attach to the stud  176  by a screw-type action. Further, the connection point between the stud  176  and the distal end of a delivery shaft can be disposed within the coupling member  174 . However, the distal end of a delivery shaft and stud  176  can be operatively connected by any mechanism which is releasable to allow the fixation device  104  to be detached. The stud can be axially extendable and retractable to move the base and therefore the legs  168  which rotate the arms  108 ,  110  between closed, open and inverted positions. Likewise, immobilization of the stud, such as by a locking mechanism  178 , can hold the legs  168  in place and therefore lock the arms  108 ,  110  in a desired position. Further details are disclosed in the patents and publications incorporated by reference herein. 
     The embodiments illustrated herein are adapted for repair of a heart valve, such as a mitral valve, using an antegrade approach from a patient&#39;s left atrium. Prior to a procedure, imaging and various tests can be performed to anticipate and diagnose a patient&#39;s individual circumstances and assist a physician in selecting a fixation device having the desired parameters. 
     While the embodiments disclosed herein utilize a push-to-open, pull-to-close mechanism for opening and closing arms it should be understood that other suitable mechanisms can be used, such as a pull-to-open, push-to-close mechanism. Likewise, other actuation elements can be used for deployment of the gripping elements. 
     While the disclosed subject matter is described herein in terms of certain preferred embodiments for purpose of illustration and not limitation, those skilled in the art will recognize that various modifications and improvements can be made to the disclosed subject matter without departing from the scope thereof. Moreover, although individual features of one embodiment of the disclosed subject matter can be discussed herein or shown in the drawings of one embodiment and not in other embodiments, it should be readily apparent that individual features of one embodiment can be combined with one or more features of another embodiment or features from a plurality of embodiments. 
     In addition to the specific embodiments claimed below, the disclosed subject matter is also directed to other embodiments having any other possible combination of the dependent features claimed below and those disclosed above. As such, the particular features presented in the dependent claims and disclosed above can be combined with each other in other possible combinations. Thus, the foregoing description of specific embodiments of the disclosed subject matter has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosed subject matter to those embodiments disclosed. 
     It will be apparent to those skilled in the art that various modifications and variations can be made in the method and system of the disclosed subject matter without departing from the spirit or scope of the disclosed subject matter. Thus, it is intended that the disclosed subject matter include modifications and variations that are within the scope of the appended claims and their equivalents.