Grip assembly for fixing device

Abstract

The present invention provides a gripping assembly for a fixation device. The present disclosure describes a tissue gripping device, system and method for gripping mitral valve tissue during treatment of the mitral valve and when a tissue fixation device is implanted in the mitral valve. The tissue gripping device includes a flexible member and one or more tissue gripping members connected to one or more arms of the flexible member. The flexible member is formed of a shape memory material such as nitinol, and the tissue gripping member is formed of a material harder than the shape memory material. The tissue gripping member is attached to the flexible member by threading or looping a suture around and / or through the tissue gripping member and the flexible member and / or by applying a covering material to the tissue gripping device to hold the tissue gripping member against the flexible member.

Description

[0001] This application is a divisional application of the invention patent application with application date of March 31, 2016, application number 201680031471.6 (PCT / US2016 / 025305), and invention name “Improved Tissue Fixation Device”.

[0002] This application claims the benefit of and priority to U.S. Patent Application No. 14 / 677,294, filed on April 2, 2015, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present invention relates generally to medical methods, medical devices and medical systems. In particular, the present invention relates to methods, devices and systems for endoluminal, percutaneous or minimally invasive surgical treatment of body tissues, such as tissue closure or valve repair. More particularly, the present invention relates to repair of heart valves or venous valves and devices and methods for removing or disabling mitral valve repair components by minimally invasive surgery. Background Art

[0004] Surgical repair of body tissues generally involves closure of the tissues and the securing of such tissues in a closure device. In the case of valve repair, closure of the tissues generally involves apposition of the leaflets of the valve in a treatment device, which can then be retained by securing or fixing the leaflets. Such securing of the leaflets can be used to treat regurgitation, which most commonly occurs in the mitral valve.

[0005] Mitral regurgitation is characterized by reverse blood flow from the left ventricle of the heart through an incompetent mitral valve into the left atrium. During a normal cycle of myocardial contraction (systole), the mitral valve acts as a check valve to prevent oxygenated blood from flowing back into the left atrium. In this way, oxygenated blood is pumped through the aortic valve into the aorta. Regurgitation of the valve can significantly reduce the pumping efficiency of the heart, putting the patient at risk for severe and progressive heart failure.

[0006] Mitral regurgitation can result from a variety of different mechanical defects in the mitral valve or the left ventricular wall. The leaflets, the chordae connecting the leaflets to the papillary muscles, the papillary muscles themselves, or the left ventricular wall may be damaged or otherwise dysfunctional. Often, the annulus may be damaged, dilated, or weakened, limiting the ability of the mitral valve to close adequately against the greater pressures of the left ventricle during systole.

[0007] The most conventional treatments for mitral regurgitation rely on valve replacement or on valve repair involving reconstruction of the valve leaflets and annulus, commonly referred to as valvuloplasty. One mitral valve repair technique that relies on suturing together adjacent segments of two opposing valve leaflets is known as the "bow tie" or "edge-to-edge" technique. While all of these techniques can be effective, they generally rely on open-heart surgery in which the patient's chest is opened, typically via a sternotomy, and the patient is placed on cardiopulmonary bypass. The need to open the chest and place the patient on cardiopulmonary bypass is invasive and has an associated high mortality and morbidity rate.

[0008] In some patients, the fixation device can be installed in the heart using minimally invasive techniques. The fixation device can hold adjacent segments of two opposing leaflets together to reduce mitral regurgitation. One device used to clamp the anterior and posterior leaflets of the mitral valve together is the Mitra Vascular sold by Abbott Vascular of Santa Clara, California. Fixtures.

[0009] These fixation devices typically include a clamp designed to grasp and hold against tissue as the clamp arms are moved and positioned against tissue at the treatment site and then closed against the tissue. These clamps are designed to continue to grasp the tissue when the fixation device is closed in the final position. To achieve this effect, these clamps are sometimes equipped with barbs or hooks to grasp the tissue as the clamp is flexed into place against the tissue.

[0010] However, some tissue fixation treatments require that the fixation device be moved through a wide range of gripping angles to properly position relative to the target tissue and then grip the tissue and place it in a closed position. Such components of the fixation device that move and plastically deform during the positioning and closing of the device can lead to weakening and premature degradation of the fixation device. In addition, some tissue fixation treatments require that the fixation device maintain a certain degree of flexibility and mobility to allow a certain range of physiological movement, even after the device has been properly placed and the target tissue has been properly fixed in the desired position. Unfavorable degradation of the device due to continued plastic deformation of the flexing components (e.g., due to continuous opening and closing of the leaflets) increases the risk of premature failure of the device.

[0011] For these reasons, there is a continuing need to provide alternative and additional methods, devices and systems for tissue fixation that provide beneficial elasticity and durability of flexure components without unduly increasing the associated manufacturing costs of the flexure components. There is also a need to provide these methods, devices and systems in a manner that does not limit the tissue grasping ability of the tissue fixation device. At least some of the embodiments disclosed below are directed to these objectives.

[0012] Minimally invasive and percutaneous techniques for apposition and modification of mitral valve leaflets for treatment of mitral regurgitation are described in PCT Publication Nos. WO98 / 35638; WO99 / 00059; WO99 / 01377; and WO00 / 03759; WO2000 / 060995; WO2004 / 103162. Maisano et al. (1998) Eur. J. Cardiothorac. Surg. 13:240-246; Fucci et al. (1995) Eur. J. Cardiothorac. Surg. 9:621-627; and Umana et al. (1998) Ann. Thorac. Surg. 66:1640-1646 describe an open surgical procedure for performing an "edge-to-edge" or "bow-tie" mitral valve repair in which the edges of the opposing leaflets are sutured together to reduce regurgitation. The nature and treatment of dilated cardiomyopathy are discussed in review articles by Dec and Fuster (1994) N. Engl. J. Med. 331: 1564-1575 and Alvarez et al. (1996) J. Thorac. Cardiovasc. Surg. 112: 238-247.

[0013] Mitral valvuloplasty is described in the following publications: Bach and Bollin (1996) Am. J. Cardiol. 78:966-969; Kameda et al. (1996) Ann. Thorac. Surg. 61:1829-1832; Bach and Bolling (1995) Am. Heart J. 129:1165-1170; and Bolling et al. (1995) 109:676-683. Linear segmental valvuloplasty for mitral valve repair is described in Ricchi et al. (1997) Ann. Thorac. Surg. 63:1805-1806. Tricuspid valvuloplasty is described in McCarthy and Cosgrove (1997) Ann. Thorac. Surg. 64:267-268; Tager et al. (1998) Am. J. Cardiol. 81:1013-1016; and Abe et al. (1989) Ann. Thorac. Surg. 48:670-676.

[0014] Percutaneous endoluminal cardiac repair procedures are described in Park et al. (1978) Circulation 58:600-608; Uchida et al. (1991) Am. Heart J. 121:1221-1224; and Ali Khan et al. (1991) Cathet. Cardiovasc. Diagn. 23:257-262. Endoluminal heart valve replacement is described in U.S. Patent Nos. 5,840,081; 5,411,552; 5,554,185; 5,332,402; 4,994,077; and 4,056,854. Patent No. 3,671,979 describes a catheter for temporary placement of an artificial heart valve.

[0015] Percutaneous and endovascular heart repair procedures are described in U.S. Patent Nos. 4,917,089; 4,484,579; and 3,874,338 and PCT Publication No. WO 91 / 01689.

[0016] Thoracoscopic and other minimally invasive heart valve repair and replacement procedures are described in U.S. Patent Nos. 5,855,614; 5,829,447; 5,823,956; 5,797,960; 5,769,812; and 5,718,725. Summary of the invention

[0017] The present disclosure describes methods and devices for grasping tissue in tissue repair and / or fixation procedures, such as in mitral valve repair procedures. Certain embodiments of the tissue grasping device include: a flexible member formed of a shape memory material, the flexible member including a base segment and an arm, the arm having a first end connected to the base segment, a free end extending away from the base segment, and an attachment surface disposed between the engagement end and the free end; and at least one tissue grasping member formed of a second material, the second material being harder than the shape memory material, the tissue grasping member including a mating surface coupled to the attachment surface of the arm to engage the tissue grasping member with the flexible member and a tissue grasping surface disposed opposite the mating surface, the tissue grasping surface including a friction element configured to hinder tissue from moving away from the tissue grasping surface after the tissue has contacted the tissue grasping surface.

[0018] A tissue fixation system configured for intravascular delivery and for engaging mitral valve tissue in the treatment of a mitral valve, the tissue fixation system comprising: a body; a proximal element, the proximal element comprising a flexible member formed of a shape memory material and at least one tissue grasping member formed of a second material, wherein the flexible member comprises a base segment and an arm, the arm having a first end connected to the base segment, a free end extending away from the base segment, and an attachment surface disposed between the engaging end and the free end, the second material being harder than the shape memory material, the tissue grasping member comprising a mating surface coupled to the attachment surface of the arm to engage the tissue grasping member with the flexible member, and a mating surface coupled to the attachment surface of the arm to engage the tissue grasping member with the flexible member. The mating surface is arranged opposite to the tissue grasping surface, and the tissue grasping surface includes a friction element configured to hinder the tissue from moving away from the tissue grasping surface after the tissue has contacted the tissue grasping surface; and a distal element, the distal element having a first end pivotally connected to the body and the first end extending to a free second end, and the distal element having a tissue engaging surface located between the first end and the second end, the tissue engaging surface being configured to approach and engage a portion of the leaflet of the mitral valve, wherein the proximal element is configured to cooperate with the distal element to form a space between the proximal element and the distal element for receiving a portion of the mitral valve tissue.

[0019] Certain embodiments of the method for manufacturing the tissue grasping device of the present disclosure include: forming a flexible member from a shape memory alloy in the following manner: cutting a pattern shape and heat setting at least one bending feature, the flexible member including a base section and an arm, the arm having a first end connected to the base section, a free end extending away from the base section, and an attachment surface arranged between the engaging end and the free end, the at least one bending feature being arranged between the first end and the free end of the arm; forming a tissue grasping member from a second material in the following manner: molding the second material to form a plurality of raised barbs and a plurality of groove-like recesses along the side edge of the tissue grasping member, the second material being harder than the shape memory material, the tissue grasping member including a mating surface and a tissue grasping surface arranged opposite to the mating surface; and attaching the tissue grasping member to the flexible member by connecting the mating surface of the tissue grasping member to the attachment surface of the arm.

[0020] Certain embodiments provide advantages and benefits over prior art tissue grasping devices, systems, and methods. For example, providing a flexible member formed of a shape memory material can provide superelasticity over a wide range of gripping angles covered during positioning of the tissue grasping device at a treatment site, such as during attempts to grasp the mitral valve leaflets during mitral valve repair surgery. In addition, avoiding plastic deformation of the flexible member during positioning and / or during post-implantation movement can increase the functionality and / or life of the device. In addition, embodiments that provide one or more tissue grasping members formed of a second material can make it easier and more cost-effective to manufacture tissue grasping friction elements and other features of tissue grasping members, compared to using shape memory materials to form tissue grasping friction elements and other features of tissue grasping members, such as by forming them directly on the flexible member. Therefore, certain embodiments can provide the benefits of superelastic properties when such properties are required, while providing these properties when greater rigidity and / or easier manufacturability are required.

[0021] These and other objects and features of the present disclosure will become fully apparent from the following description and appended claims, or may be obtained by the practice of the embodiments of the invention as set forth hereinafter. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to further illustrate the above and other advantages and features of the present disclosure, the present invention will be described in more detail with reference to specific embodiments of the present invention illustrated in the accompanying drawings. It should be understood that these drawings depict only illustrative embodiments of the present invention and are therefore not to be considered as limiting the scope of the present invention. Embodiments of the present invention will be described and illustrated with additional features and details through the use of the accompanying drawings, in which:

[0023] Figure 1 The free edges of the mitral valve leaflets during normal coaptation are shown, and Figure 2 The free edge is shown in the state of regurgitant apposition;

[0024] FIG. 3A to FIG. 3C The figures respectively illustrate grasping of the leaflets with the fixation assembly, inversion of the distal element of the fixation assembly, and removal of the fixation assembly;

[0025] Figure 4 The fixation assembly is illustrated in a desired orientation relative to the leaflets;

[0026] Figure 5 An exemplary fixing assembly coupled to a shaft is illustrated;

[0027] FIG. 6A to FIG. 6B , 7A to 7C and Figure 8The fixation assembly is illustrated in various possible positions during introduction and deployment of the assembly within the body for a therapeutic procedure;

[0028] 9A to 9C illustrates a detailed view of a proximal element of a tissue fixation device, the proximal element including a flexible member and a plurality of tissue grasping members;

[0029] FIG. 10A to FIG. 10C illustrates a detailed view of a proximal element of a tissue fixation device, wherein a plurality of tissue grasping members are joined to a flexible member via sutures; and FIG. 11A to FIG. 11C A detailed view of a proximal element of a tissue fixation device is illustrated, wherein the proximal element has a cover and a plurality of tissue grasping members are held against a flexible member by the cover. DETAILED DESCRIPTION

[0030] I. Cardiac Physiology

[0031] like Figure 1 As shown in , the mitral valve (MV) includes a pair of leaflets (LF) with free edges (EF) that meet evenly to close along the line of apposition (C) in patients with normal heart structure and function. The leaflets (LF) are attached to the surrounding heart structures along an annular region called the annulus (AN). The free edges (FE) of the leaflets (LF) are fixed to the lower part of the left ventricle (LV) by chordae tendineae (or "tendons"). When the left ventricle of the heart contracts (this is called "systole"), blood flow from the left ventricle through the mitral valve (MV) to the left atrium (known as "mitral regurgitation") is usually blocked by the mitral valve. Regurgitation occurs when the leaflets do not close completely and allow leakage from the left ventricle into the left atrium. Many structural defects of the heart can cause mitral regurgitation. Figure 2 A mitral valve is shown with a defect causing regurgitation through the gap (G).

[0032] II. Overview of Mitral Valve Fixation Systems

[0033] There are several methods for repairing or replacing a defective mitral valve. Some defects of the mitral valve can be treated by endovascular surgery, in which interventional tools and interventional devices are introduced into and removed from the heart through blood vessels. One method of repairing certain mitral valve defects includes intravascular delivery of a fixation device to hold a portion of mitral valve tissue in a specific position. The fixation device can be delivered to the mitral valve using one or more interventional catheters and installed at the mitral valve as an implant for treating mitral regurgitation.

[0034] Figure 3AA schematic diagram of an interventional tool 10 having a delivery shaft 12 and a fixture 14 is illustrated. The interventional tool 10 has approached the mitral valve MV from the atrial side and grasped the leaflets LF. The fixture 14 is releasably attached to the shaft 12 of the interventional tool 10 at the distal end of the shaft 12. In the present application, when describing a device, "proximal" refers to the direction toward the end of the device to be manipulated by the user outside the patient's body, and "distal" refers to the direction toward the working end of the device positioned at the treatment site and away from the user. When describing the mitral valve, the proximal end refers to the atrial side of the leaflets, and the distal end refers to the ventricular side of the leaflets. The fixture 14 includes a proximal element 16 and a distal element 18, which protrude radially outward and can be positioned on opposite sides of the leaflets LF as shown to capture or hold the leaflets between the proximal element 16 and the distal element 18. The fixture 14 can be coupled to the shaft 12 by a coupling mechanism 17.

[0035] Figure 3B The distal element 18 is shown as being movable in the direction of arrow 40 to an inverted position. The proximal element 16 may be as shown. Figure 3C In the reverse position, the device 14 can be repositioned and then reversed to the position shown in FIG. Figure 3A Alternatively, the fixing device 14 may be as follows Figure 3C 4. The inversion may reduce damage to the leaflets and may minimize any entanglement of the device with surrounding tissue.

[0036] Figure 4 The fixation device 14 is shown in a desired orientation relative to the leaflets LF. Since the mitral valve MV is viewed from the atrial side, the proximal elements 16 are shown in solid lines and the distal elements 18 are shown in dashed lines. The proximal elements 16 and the distal elements 18 are positioned generally perpendicular to the line of apposition C. During diastole (when blood flows from the left atrium to the left ventricle), the fixation device 14 holds the leaflets LF in place between the elements 16, 18 surrounded by the opening or orifice O created by the diastolic pressure gradient, as shown in FIG. Figure 4 Once the leaflets are approximated in the desired arrangement, the fixation device 14 is detached from the shaft 12 and left as an implant.

[0037] Figure 5An exemplary fixture 14 is illustrated. The fixture 14 is shown coupled to the shaft 12 to form the interventional tool 10. The fixture 14 includes a coupling member 19, a pair of opposing proximal elements 16, and a pair of opposing distal elements 18. The distal element 18 includes an elongated arm 53, each arm having a free end 54 and a proximal end 52 rotatably connected to the coupling member 19. Preferably, each free end 54 defines a curvature about two axes: an axis 66 perpendicular to the longitudinal axis of the arm 53 and an axis 67 perpendicular to the axis 66 or the longitudinal axis of the arm 53. The arm 53 has an engagement surface 50. The arm 53 and the engagement surface 50 are configured to engage tissue of about 4mm-10mm, and preferably engage tissue of about 6mm-8mm along the longitudinal axis of the arm 53. The arm 53 also includes a plurality of openings.

[0038] The proximal elements 16 are preferably resiliently biased toward the distal elements 18. When the fixation device 14 is in the open position, each proximal element 16 is separated from the engagement surface 50 near the proximal end 52 of the arm 53 and tilted toward the engagement surface 50 near the free end 54, so that the free end of the proximal element 16 contacts the engagement surface 50, as shown in FIG. Figure 5 As shown in . The proximal element 16 includes a plurality of openings 63 and a scalloped side edge 61 to enhance its grip on tissue. The proximal element 16 optionally includes a friction element or multiple friction elements to assist in gripping the leaflet. The friction element may include a barb 60 having a tapered tip extending toward the engagement surface 50. Any suitable friction element may be used, such as a fork, wing, ribbon, barb, groove, channel, protrusion, surface wrinkle, sinter, high friction pad, covering, coating or a combination of these. The proximal element 16 may be covered with fabric or other flexible material. Preferably, when a fabric or covering is used in combination with a barb or other friction feature, these features will extend through these fabrics or other coverings to contact any tissue engaged by the proximal element 16.

[0039] The fixture 14 also includes an actuator or actuation mechanism 58. The actuation mechanism 58 includes two connecting members or legs 68, each leg 68 having a first end 70 and a second end 72, wherein the first end 70 is rotatably engaged with one of the distal elements 18 at a riveted joint 76, and the second end 72 is rotatably engaged with a stud 74. The actuation mechanism 58 includes two legs 68 each movably coupled to a base 69. Alternatively, each leg 68 can be attached to the stud 74 by a separate rivet or pin. The stud 74 can engage with an actuator rod that extends through the shaft 12 and can be extended and retracted axially to move the stud 74 and thus the legs 68, thereby rotating the distal element 18 between the closed position, the open position, and the reverse position. The actuation of the stud 74 can hold the legs 68 in place and thus the distal element 18 in a desired position. The stud 74 can also be locked in place by a locking feature. The actuator rod and stud assembly can be considered as a first means for selectively moving the distal element between a first position, in which the distal element is in a collapsed, low-volume configuration to facilitate delivery of the device, a second position, in which the distal element is in an expanded configuration to position the device relative to the mitral valve, and a third position, in which the distal element is fixed in place against a portion of the leaflet adjacent to the mitral valve on the ventricular side.

[0040] FIG. 6A to FIG. 6B , 7A to 7C and Figure 8 Shows Figure 5 Various possible positions of the fixing device 14. Fig. 6A The interventional tool 10 is shown being delivered through a catheter 86. The catheter 86 may take the form of a guide catheter or a sheath. The interventional tool 10 includes a fixation device 14 coupled to a shaft 12, and the fixation device 14 is shown in a closed position.

[0041] Figure 6B The larger diagram shows Fig. 6A In the closed position, the pair of opposed distal elements 18 are positioned so that the engagement surfaces 50 face each other. Each distal element 18 includes an elongated arm 53 having a cup-like or concave shape so that the arms 53 collectively surround the shaft 12. This provides a smaller volume for the fixation device 14.

[0042] FIG. 7A to FIG. 7BThe fixture 14 is shown in an open position. In the open position, the distal element 18 is rotated so that the engagement surface 50 faces the first direction. The actuator rod relative to the shaft 12 to the distal end of the advancement and therefore the stud 74 relative to the coupling member 19 to the distal end of the advancement movement applies a force to the distal element 18, and the distal element 18 begins to rotate around the joint 76. This radially outward rotation and movement of the distal element 18 rotates the legs 68 around the joint 80 so that the legs 68 are slightly guided outward. The stud 74 can advance any desired distance associated with the desired separation of the distal element 18. In the open position, the engagement surface 50 is arranged at an acute angle relative to the shaft 12, and preferably at an angle between 90 degrees and 180 degrees relative to each other. In the open position, the free ends 54 of the arms 53 have a span of about 10mm-20mm, typically about 12mm-18mm and preferably about 14mm-16mm between them.

[0043] The proximal element 16 is typically biased outwardly toward the arm 53. The proximal element 16 can be moved inwardly toward the shaft 12 and held against the shaft 12 by means of a proximal element wire 90 in the form of a suture, wire, nickel-titanium alloy wire, rod, cable, polymer wire, or other suitable structure. The proximal element wire 90 extends through the shaft of the delivery catheter and is connected to the proximal element 16. The proximal element 16 is raised or lowered by manipulation of the proximal element wire 90. For example, Figure 7C The proximal element 16 is illustrated in a lowered position due to slackening of the proximal element wire 90. Once the device is properly positioned and deployed, the proximal element wire can be removed by retracting it through the catheter and away from the proximal end of the interventional tool 10. The proximal element wire 90 can be viewed as a second means for selectively moving the proximal element between a first position, in which the proximal element is in a contracted, low-volume configuration to facilitate delivery of the device, and a second position, in which the proximal element is in an expanded configuration to engage portions of the leaflets adjacent to the mitral valve on the atrial side.

[0044] In the open position, the fixture 14 can engage the tissue to be closed or treated. The interventional tool 10 advances from the left atrium through the mitral valve to the left ventricle. The distal element 18 is then deployed in the following manner: the actuator rod is advanced relative to the shaft 12 so as to redirect the distal element 18 to be perpendicular to the line of coaptation. The entire assembly is then retracted at the proximal end and positioned so that the engagement surface 50 contacts the ventricular surface of the leaflet, thereby engaging the left ventricular side surface of the leaflet. The proximal element 16 remains on the left atrial side of the leaflet so that the leaflet is located between the proximal element and the distal element. The interventional tool 10 can be repeatedly manipulated to reposition the fixture 14 so that the leaflet is properly contacted or grasped at the desired position. Repositioning is achieved by the fixture in the open position. In some cases, regurgitation can also be checked when the device 14 is in the open position. If the regurgitation is not satisfactorily reduced, the device can be repositioned and the regurgitation is checked again until the desired result is obtained.

[0045] It may also be desirable to invert the distal element 18 of the fixation device 14 to assist in repositioning or removal of the fixation device 14 . Figure 8 The fixture 14 is shown in the reversed position. By further advancement of the actuator rod relative to the shaft 12 and thus further advancement of the stud 74 relative to the coupling member 19, the distal element 18 is further rotated so that the engagement surface 50 faces outward and the free end 54 points distally so that each arm 53 forms an obtuse angle relative to the shaft 12.

[0046] When the device is reversed, the angle between the arms 53 is preferably in the range of about 270 degrees to 360 degrees. Further advancement of the stud 74 also rotates the distal element 18 around the joint 76. This radially outward rotation and movement of the distal element 18 rotates the legs 68 around the joint 80 so that the legs 68 return to their initial position roughly parallel to each other. The stud 74 can be advanced to any desired distance associated with the desired reversal of the distal element 18. Preferably, in the fully reversed position, the span between the free ends 54 does not exceed about 20 mm, is typically less than about 16 mm, and is preferably about 12 mm-14 mm. The barbs 60 are slightly angled in the distal direction (away from the free end of the proximal element 16), thereby reducing the risk that the barbs will hook or tear tissue when the fixture is retracted.

[0047] Once the distal element 18 of the fixation device 14 has been positioned in the desired position against the left ventricular lateral surface of the leaflets, the leaflets can be captured between the proximal element 16 and the distal element 18. The proximal element 16 is lowered toward the engagement surface 50 by releasing tension from the proximal element wire 90, thereby releasing the proximal element 16, so that the proximal element 16 is free to move from the constrained, retracted position to the expanded, deployed position in response to an internal spring biasing force formed in the proximal element 16, and so that the leaflets are retained between the proximal element 16 and the distal element 18. If regurgitation is not satisfactorily reduced, the proximal element 16 can be raised and the distal element 18 adjusted or reversed to reposition the fixation device 14.

[0048] After the leaflets have been captured between the proximal element 16 and the distal element 18 in the desired setting, the distal element 18 can be locked to hold the leaflets LF in this position, or the fixture 14 can be returned to or toward the closed position. This is achieved by the stud 74 being retracted proximally relative to the coupling member 19 so that the legs 68 of the actuating mechanism 58 apply an upward force to the distal element 18, which in turn causes the distal element 18 to rotate so that the engagement surfaces 50 face each other again. The released proximal element 16, which is biased outwardly toward the distal element 18, is simultaneously pushed inwardly by the distal element 18. The fixture 14 can then be locked to hold the leaflets in the closed position. The fixture 14 can then be released from the shaft 12.

[0049] The fixture 14 optionally includes a locking mechanism for locking the device 14 in a specific position such as an open position, a closed position or an inverted position or in any position between the open position, the closed position and the inverted position. The locking mechanism may include a release band. Applying tension to the release band can unlock the locking mechanism. A lock wire 92 engages the release band of the locking mechanism to lock and unlock the locking mechanism. The lock wire 92 extends through the shaft of the delivery catheter. The fixture 14 is manipulated and disconnected using a handle attached to the proximal end of the shaft.

[0050] Additional disclosure regarding such a securing device 14 may be found in PCT Publication No. WO 2004 / 103162 and US Patent Application No. 14 / 216,787, the disclosures of both of which are incorporated herein in their entirety.

[0051] III. Improved tissue fixation device

[0052] Certain embodiments of the tissue fixation devices of the present disclosure include a proximal element 16 formed as a tissue grasping device as described in detail below. In some embodiments, the tissue grasping device can form a tissue fixation device (e.g., as described above with reference to FIGS. 3 to 4). Figure 8The proximal element 16 of any tissue fixation device 14 described in the related discussion) and the tissue grasping device can be used as the proximal element 16 of the tissue fixation device. Therefore, the terms "tissue grasping device" and "proximal element" defined herein are interchangeable.

[0053] 9A to 9C An embodiment of a tissue grasping device 100 is illustrated, and the tissue grasping device 100 includes a flexible member 102 and at least one tissue grasping member 122 coupled to the flexible member 102 (e.g., a pair of tissue grasping members 122 as illustrated). The flexible member 102 can be formed of a first material, and the tissue grasping member 122 can be formed of a second, different material. In a preferred embodiment, the second material has a greater rigidity than the first material, such that the tissue grasping member 122 is harder than the flexible member 102. Therefore, in such an embodiment, the flexible member 102 is more bendable than the tissue grasping member 122. The flexible member 102 is preferably made of a shape memory material such as Nitinol. In this configuration, the flexible member 102 exhibits superelasticity during flexing, bending, and / or otherwise positioning the tissue grasping device 100 (e.g., during positioning and deployment of the device at a treatment site and / or during continued movement after deployment).

[0054] For example, during a mitral valve repair procedure, a portion of the tissue grasping device may need to repeatedly traverse larger angles as multiple tissue grasping attempts are made and / or as the tissue grasping device 100 is moved into an acceptable position against the leaflets of the mitral valve. Additionally, even after being deployed against the mitral valve tissue, the tissue grasping device 100 may need to provide a certain amount of flexibility and movement as the repaired mitral valve tissue continues to move during the cardiac cycle. Forming the flexible member 102 from a shape memory material, such as nitinol, avoids plastic deformation of the flexible member 102 during these movements, thereby promoting easier tissue grasping during deployment and reducing mechanical degradation of the tissue grasping device 100 due to repeated plastic deformation and / or higher levels of plastic deformation.

[0055] The tissue grasping member 122 may be formed of stainless steel or a cobalt-chromium alloy, such as a cobalt-chromium-nickel alloy or a cobalt-chromium-nickel-iron-molybdenum-manganese alloy. However, any suitable material or combination of materials may be used. For example, the tissue grasping member 122 may be formed of a material from which the friction elements 128 (e.g., raised barbs) or other features of the tissue grasping member are easily machined or otherwise formed (e.g., easier to machine than using a shape memory material to machine these features, such as machining the friction elements 128 directly onto the arms 106 of the flexible member 102).

[0056] The flexible member 102 includes a proximal side 114, a distal side 116, a base section 104, and a pair of arms 106, wherein each arm 106 extends from the base section 104 to a free end 108. In other embodiments, there may be one arm extending from the base section, or there may be more than two arms extending from the base section. For example, some embodiments may have multiple arms arranged around the base section (e.g., in a radial manner), and / or may include multiple first arms and multiple second arms disposed opposite the multiple first arms.

[0057] Each arm in the illustrated embodiment includes a first bending feature 110 disposed at an area adjacent to the base section 104 and a second bending feature 112 disposed at a greater distance from the free end 108 than the first bending feature 110. The first bending feature 110 forms an angle of about 90 degrees or slightly less than 90 degrees (e.g., about 60 degrees to 120 degrees, about 70 degrees to 110 degrees, or about 80 degrees to 100 degrees) measured relative to the proximal side 114, and the second bending feature 112 forms an angle of about 90 degrees or slightly less than 90 degrees (e.g., greater than about 60 degrees to 120 degrees, about 70 degrees to 110 degrees, or about 80 degrees to 100 degrees) measured relative to the distal side 116.

[0058] The first bending feature 110 and the second bending feature 112 are configured to impart a bending configuration to the flexible member 102 when the flexible member 102 is in a relaxed state, such that when the flexible member 102 is forced into a stressed state (e.g., by causing the flexible member 102 to bend at one or more of the first bending feature 110 and / or the second bending feature 112), the flexible member 102 is elastically biased toward the relaxed state.

[0059] For example, the arm 106 can be deformed at the second bending feature 112 in the following manner: the arm 106 is flexed in the proximal direction and the inward direction, thereby flexing the arm 106 to a straighter configuration (e.g., increasing the angle of the second bending feature 112 measured relative to the distal side 116). In such a position, the flexible member 102 is in a stressed state, so that the arm 106 of the flexible member 102 is elastically biased toward the distal direction and the outward direction. Other embodiments may omit one or more of the bending features, and other embodiments may include additional bending features. These and other embodiments may include bending features with different bending angles when in a relaxed state. For example, some embodiments may include bending features that are measured to be greater than about 90 degrees or less than about 90 degrees when in a relaxed state.

[0060] The flexible member 102 of the illustrated embodiment includes a plurality of holes 118 distributed along the length of each arm 106. The holes 118 are configured to provide passageways or attachment points for one or more sutures, wires, nitinol wires, rods, cables, polymer wires, or other such structures. As discussed above, these materials can be coupled to one or more arms 106 to serve as proximal element wires (e.g., 7A to 7C 102) is operative to raise, lower, and otherwise manipulate, position, and / or deploy the flexible member 102. Additionally or alternatively, the aperture 118 may be configured to provide coupling of the flexible member 102 to one or more tissue grasping members (as discussed in detail below).

[0061] Other embodiments may include flexible members having more or fewer holes and / or holes located in other locations of the flexible member. For example, some embodiments may omit holes entirely, and some embodiments may include only one hole and / or only one hole per arm. Other embodiments may include holes of different shapes and / or sizes, such as holes formed as slots, slits, or other shapes. In embodiments including more than one hole, the holes may be uniform in size, shape, and distribution, or may be non-uniform in one or more of size, shape, and distribution.

[0062] Each arm 106 of the illustrated embodiment includes a forked section 120. The forked section 120 can extend from the base section 104 along the arm 106 toward the free end 108 of the arm 106 to a remote position, as shown. In other embodiments, the forked section can be positioned at other positions along the arm and / or the base section. Other embodiments may include one or more forked sections that extend completely to the free end of the arm to form a forked arm or a forked arm. Other embodiments omit any forked section. The forked section 120 of the illustrated embodiment is consistent with the second bending feature 112. The forked section 120 can be configured to provide desired elasticity and / or flexibility at the consistent second bending feature 112 (e.g., in terms of size, shape, spacing, position, etc.).

[0063] The illustrated embodiment includes a pair of tissue grasping members 122, each having a mating surface 124 and a tissue grasping surface 126. Each tissue grasping member 122 includes a plurality of friction elements 128 configured to engage with tissue at the treatment site and to hinder tissue movement away from the tissue grasping member after the friction elements 128 have engaged the tissue. As shown in the illustrated embodiment, the friction elements 128 are formed as angled barbs extending distally and inwardly. In this way, tissue engaged with the friction elements 128 of the tissue grasping member 122 is prevented from moving proximally and outwardly relative to the tissue grasping member 122.

[0064] The friction elements 128 of the illustrated tissue grasping member 122 protrude from the side edges 130 of the tissue grasping member 122, thereby forming a plurality of groove-like recesses 132 disposed at sections adjacent to the friction elements 128 along each side edge 130 of each tissue grasping member 122. Other embodiments may include only one tissue grasping member or may include more than two tissue grasping members. For example, some embodiments may include a plurality of separately formed tissue grasping members configured to be coupled to each arm. In other embodiments, not each arm includes a corresponding tissue grasping member. Other embodiments may include friction elements of different sizes, quantities, and / or shapes. For example, in some embodiments, the friction elements may be formed as columns, teeth, forks, strips, grooves, channels, protrusions, pads, or a combination of these features or any other features suitable for increasing the friction and / or gripping force of the contacted tissue.

[0065] The tissue grasping members 122 of the illustrated embodiment include a plurality of holes 138 distributed along the length of each tissue grasping member 122. As with the holes 118 of the flexible member 102, the holes 138 of the tissue grasping members 122 are configured to provide a plurality of holes 138 for use as a proximal element line (e.g., 7A to 7COne or more sutures, wires, nitinol wires, rods, cables, polymer wires, or other such structures operated by the element line 90 (illustrated in FIG. 1 ) provide a channel or connection point and / or provide a connection between one or more tissue grasping members 122 and the flexible member 102.

[0066] The apertures 138 of the tissue grasping member 122 of the illustrated embodiment are formed to coincide with the apertures 118 of the flexible member 102. In this manner, the tissue grasping member 122 can be positioned relative to the flexible member 102 such that each of the apertures 138 of the tissue grasping member 122 is aligned with a corresponding aperture 118 of the flexible member 102.

[0067] Other embodiments may include tissue gripping members having more or fewer holes and / or holes located in other locations of the tissue gripping member. For example, some tissue gripping members may omit the hole, or may include only one hole. Other embodiments may include holes of different shapes - for example, slot-shaped, slit-shaped, or other shapes - and / or different sizes. In embodiments including more than one hole, the holes may be consistent in size, shape, and distribution, or may be non-consistent in one or more of size, shape, and distribution. In other embodiments, not every hole of the tissue gripping member is configured to align with a corresponding hole of the flexible member, and not every hole of the flexible member is configured to align with a corresponding hole of the tissue gripping member. In some embodiments, there is no hole alignment when the tissue gripping member is properly positioned relative to the flexible member.

[0068] In the illustrated embodiment, the distal side of each arm 106 of the flexible member 102 includes an attachment surface 134. The tissue grasping member 122 is positioned on the distal side of the arm 106 of the flexible member 102, wherein the mating surface 124 of the tissue grasping member 122 faces the attachment surface 134. The tissue grasping member 122 is engaged to the flexible member 102 by coupling the mating surface 124 to the attachment surface 134. In other embodiments, the mating surface and the attachment surface can be formed to have corresponding press-fit portions or other locking / engaging portions, and the corresponding press-fit portions or other locking / engaging portions are configured to allow the tissue grasping member to be engaged to the flexible member by engaging the corresponding press-fit portions and / or other corresponding locking portions. In some embodiments, the tissue grasping member can be fastened to the flexible member using an adhesive or by welding, brazing, bolting, clamping, riveting, crimping or otherwise fixing the tissue grasping member to the flexible member.

[0069] In some embodiments, the arms of the flexible member are configured to bend proximally when moving from a relaxed configuration toward a stressed configuration and to elastically flex distally toward the relaxed configuration when positioned in a stressed configuration, thereby forcing the attachment surface of the arm to abut the tissue grasping member when the arm flexes distally toward the relaxed configuration. For example, when the tissue grasping device is properly positioned and deployed at the mitral valve, the arms of the flexible member will operate to "sandwich" the tissue grasping member between the arms and the grasped mitral valve tissue.

[0070] FIG. 10A to FIG. 10C An embodiment of the tissue grasping device 200 is illustrated in which a tissue grasping member 222 has been coupled to the flexible member 202. In the illustrated embodiment, each tissue grasping member 222 has been positioned adjacent to the flexible member 202 by engaging each mating surface (not shown) of each tissue grasping member 222 to one of the corresponding attachment surfaces (not shown) of the flexible member 202. In the illustrated embodiment, the tissue grasping member 222 is secured to the flexible member 202 by forming a sewing loop 240 through the aligned holes 218 and 238 of the flexible member 202 and the tissue grasping member 222, respectively. In this configuration, the sewing loop 240 can secure the tissue grasping member 222 to the flexible member 202 by encircling at least a portion of the tissue grasping member and at least a portion of the arm 206 of the flexible member 202 before being tied, tightened, or otherwise secured to hold the tissue grasping member 222 in place against the flexible member 202.

[0071] In other embodiments, one or more sutures may be used to tie or secure one or more tissue grasping members to the flexible member in other configurations. For example, one or more sutures may be threaded or tied through multiple holes on both the tissue grasping member and the flexible member before being knotted, tightened, or otherwise secured in place to secure the tissue grasping member to the flexible member. In other embodiments, one or more sutures do not pass through any holes. In such embodiments, the sutures may be looped or wrapped around the arms of the flexible member and the tissue grasping member to secure the tissue grasping member to the arms.

[0072] The sutures forming the suture loop 240 or other suture fastening structure may be wound and / or threaded one or more times before being tied, tightened, or otherwise set in place. For example, some sutures may be repeatedly wound and / or may be folded in half upon themselves to strengthen or further secure the connection of the tissue grasping member to the arm. In some embodiments, one or more of the sutures used to form the suture loop 240 or other suture fastening structure may also extend from the tissue grasping device 200 to serve as the element line described above (e.g., 7A to 7C Component line 90 shown in FIG.

[0073] The tissue grasping member 222 of the illustrated embodiment also includes a plurality of slotted recesses 232. In embodiments such as these, one or more sewing rings 240 can be formed such that sutures are passed through and received in the oppositely disposed slotted recesses 232, thereby further assisting in securing the tissue grasping member 222 to the arm 206 and promoting proper placement of the sewing rings 240 and preventing the inner sewing ring 240 from sliding, becoming loose, or unraveling from its proper position.

[0074] In other embodiments, the sewing ring or other suture fastening structure does not pass through and is not accommodated in any slot recess. Some embodiments may include a sewing ring and / or suture fastening structure that passes through and / or is accommodated in one or more (not necessarily oppositely arranged) slot recesses to assist in fastening the tissue grasping member to the arm of the flexible member. Still other embodiments may include sutures that form sewing rings and other suture fastening structures that pass through and / or are accommodated in one or more slot recesses but do not pass through any holes. Conversely, some embodiments may include sutures that form sewing rings or other suture fastening structures that pass through one or more holes but do not pass through and / or are not accommodated in any slot recesses.

[0075] The illustrated embodiment includes two suture rings 240 at each tissue grasping member 222. In other embodiments, more or fewer suture rings or suture fastening structures may be used, but in a preferred embodiment, at least two fastening points are formed (e.g., by using two or more suture rings or by threading or lacing sutures through multiple points) to prevent the tissue grasping member from rotating and sliding from the flexible member due to torque.

[0076] FIG. 11A to FIG. 11C An embodiment of a tissue grasping device 300 is illustrated in which a tissue grasping member 322 has been coupled to a flexible member 302 using at least one cover 350. The cover 350 is positioned over at least a portion of the arms 306 of the flexible member 302 and over at least a portion of the tissue grasping member 322 to hold the tissue grasping member 322 against the arms 306.

[0077] In a preferred embodiment, the cover 350 is formed as a polymer cover that can be formed on the tissue grasping device 300 by dipping, spraying, coating, or otherwise adhering the polymer cover to a surface of the tissue grasping device 300 or a portion of the tissue grasping device 300. In some embodiments, a polymer coating can be applied to the tissue grasping member 322 and the arm 306 (or a portion thereof) while the tissue grasping member 322 is held in place against the flexible member 302. The polymer coating can then cure, harden, and / or solidify to form the cover 350 and hold the tissue grasping member 322 against the flexible member 302. In other embodiments, the polymer coating can be used as an adhesive, and the polymer coating can be applied to a mating surface (not shown) and / or an attachment surface (not shown) to adhere the tissue grasping member 322 to the arm 306 when the mating surface is positioned against the attachment surface and the polymer coating is cured.

[0078] The cover 350 can be formed in whole or in part from polyethylene terephthalate, polyester, cotton, polyurethane, expanded polytetrafluoroethylene (ePTFE), silicon, or various biocompatible polymers or fibers, and has any suitable form, such as a fabric, a mesh, a textured braid, felt, a ring structure, or a porous structure. The cover 350 can also be configured to expose the friction element 328 (in an embodiment including the friction element 328). The cover 350 can also include drugs, antibiotics, antithrombotic agents, or antiplatelet agents such as heparin or warfarin sodium. These agents can be impregnated in and / or coated on the cover 350 so that these agents are delivered to the surrounding tissue and / or bloodstream when the tissue grasping device 300 is implanted in the patient's body.

[0079] FIG. 11A to FIG. 11C The embodiment illustrated in includes some covers 350 positioned over the entirety of each tissue grasping member 322 and over the portion of the arm 306 adjacent to each tissue grasping member 322. In other embodiments including covers, the covers can be positioned to cover a majority of the tissue grasping device or even the entire tissue grasping device (e.g., the entire device can be sprayed, dipped, or otherwise coated with a polymer coating forming the cover). Alternatively, some embodiments may include covers (such as covers positioned over lesser portions of the tissue grasping device to leave other portions of the tissue grasping members and / or arms (e.g., inner portions and / or outer portions) exposed. FIG. 11A to FIG. 11C Some of the covers 350 shown in FIG.

[0080] In some embodiments, one or more tissue grasping members may be used in addition to FIG. 11A to FIG. 11C In addition to the cover being held in place as discussed above, it is also possible to use a cover as discussed above. FIG. 10A to FIG. 10C The suture discussed above is coupled to the arms of the flexible member. For example, one or more suture loops and / or suture fastening structures may be used to fasten one or more tissue grasping members to the flexible member. Thereafter (or alternatively before or simultaneously), a polymer coating may be applied to form a covering around at least a portion of the tissue grasping member and at least a portion of the conforming arms.

[0081] IV. Manufacturing Method

[0082] Embodiments of the tissue grasping device disclosed herein can be manufactured by forming a flexible member from a shape memory material (e.g., Nitinol). Forming the flexible member can be achieved by cutting a pattern shape from a sheet of shape memory material (or alternatively, a strip or ribbon blank or other form of blank). Individual features (e.g., bifurcated segments, holes, etc.) can optionally be formed in the flexible element during or after the flexible element is initially formed from the blank material. This can be accomplished using any suitable subtractive manufacturing process, such as drilling, turning, molding, cutting, etc. In some embodiments, additional features can be added using an additive manufacturing process. In other embodiments, additional features or elements are not formed by any subtractive or additive manufacturing process.

[0083] In some embodiments, the flexible member can be further processed by a shaping process. For example, one or more bending features can be formed in the flexible member by subjecting the flexible member to a heat-setting process to set a bending shape in the shape memory material of the flexible member.

[0084] In some embodiments, one or more tissue grasping members are formed separately from the flexible member. Forming the tissue grasping members can be accomplished by cutting and / or progressive molding processes of a material having suitable machining properties for such a manufacturing process. For example, the material forming the one or more tissue grasping members can be obtained by cutting and / or molding a shape from a sheet blank (or alternatively, a strip or ribbon blank or other form of blank). For example, the blank material can be stainless steel or a cobalt-chromium alloy, such as a cobalt-chromium-nickel alloy or a cobalt-chromium-nickel-iron-molybdenum-manganese alloy. In a preferred embodiment, the tissue grasping member is made of Formation. As the tissue grasping member is formed from the blank material, various features (eg, holes, friction elements, slot-like recesses, etc.) may be formed on the tissue grasping member.

[0085] In some embodiments, the tissue grasping member can be further manufactured by a single molding process or a progressive molding process. For example, the tissue grasping member can be subjected to a progressive molding process to form and / or further define various features on the tissue grasping member, such as a plurality of raised barbs and groove-like recesses.

[0086] In some embodiments, after forming the flexible member and the tissue grasping member, the tissue grasping member is formed by attaching the mating surface of the tissue grasping member (e.g., 9A to 9C The mating surface 124 of the embodiment of the present invention is connected to the attachment surface of the flexible member (e.g., 9A to 9C The tissue grasping member may then be further secured to the flexible member.

[0087] For example, as in FIG. 10A to FIG. 10C As shown in the exemplary embodiment of FIG. 1 , one or more sutures may be wound around a portion of the tissue grasping member and a portion of the flexible member (eg, an arm portion, such as FIG. 10A to FIG. 10C The suture may be formed into a loop or may be threaded or wound around the tissue grasping member and the arm (or other portion of the flexible member) before being tightened and / or knotted to secure the tissue grasping member to the flexible member.

[0088] In some embodiments, the tissue grasping member and / or the flexible member may include holes, and the one or more sutures may be passed through one or more of the holes to secure or further fix the tissue grasping member to the flexible member. Figures 10A to 10C As shown in the embodiment illustrated in FIG, the tissue grasping member can have a plurality of holes, wherein each hole is configured to correspond to a hole on the arm of the flexible member when the tissue grasping member is appropriately positioned near or against the arm of the flexible member. One or more sutures can pass through one or more pairs of corresponding holes when they are tied, wrapped, looped, or threaded around the tissue grasping member and the arm.

[0089] In some embodiments, one or more sutures may also pass through or be contained within the slotted recess of the tissue grasping member as it is tied, wound, looped, or threaded around the tissue grasping member and the arms. In such embodiments, the slotted recess may further assist in securing the suture in place and / or prevent the suture from loosening, sliding, or other unwanted movement.

[0090] Additionally or alternatively, the tissue grasping member may be secured or further secured to the flexible member by adding a cover to the tissue grasping device, wherein the cover is inserted over the arms of the flexible member and the tissue grasping member (or a portion of the tissue grasping member) to hold the tissue grasping member in place against the flexible member.

[0091] For example, in some embodiments (such as in FIG. 11A to FIG. 11C), the covering can be a polymer material that is coated or otherwise applied to the tissue grasping device (or a portion of the tissue grasping device). The polymer coating can then be allowed to set, cure, or otherwise form a covering that holds the tissue grasping member in place against the arms of the flexible member. Additionally or alternatively, the polymer coating can act as an adhesive and can be applied to the mating surface and / or the attachment surface to adhere the surfaces together.

[0092] The present invention may be implemented in other specific forms without departing from the spirit or essential features of the present invention. The described embodiments are considered to be illustrative and non-restrictive in all respects. Therefore, the scope of the present invention is specified by the appended claims rather than by the preceding description. All changes falling within the equivalent meaning and scope of the claims are included within the scope of the claims.

Claims

1. A gripping assembly for a fixing device, the gripping assembly comprising: a flexible member comprising a base section and an arm extending from the base section, the arm having a first end connected to the base section, a free end extending away from the base section, an attachment surface disposed between the first end and the free end, and at least one opening defined in the attachment surface; as well as A tissue grasping member, the tissue grasping member comprising: a mating surface configured to engage the attachment surface of the arm, and a tissue grasping surface configured to engage tissue of a native heart valve leaflet, the tissue grasping member further comprising a plurality of barbs configured to resist movement of tissue relative to the tissue grasping surface, wherein the tissue grasping member has at least one opening defined therein and the tissue grasping member is attached to the arm by a suture extending through the at least one opening of the tissue grasping member and the at least one opening of the arm, and Wherein, the flexible member is more bendable than the tissue grasping member.

2. The gripping assembly according to claim 1, wherein: The flexible member is made of Nitinol.

3. The gripping assembly according to claim 1, wherein: The flexible member is made of a first material and the tissue grasping member is made of a second material, wherein the first material is different from the second material.

4. The gripping assembly according to claim 3, wherein: The first material is more flexible than the second material.

5. The gripping assembly of claim 1, wherein: The tissue grasping member is made of a material selected from the group consisting of: cobalt-chromium alloy and stainless steel.

6. The gripping assembly of claim 1, wherein: The plurality of barbs are arranged along a side edge of the tissue grasping member, the tissue grasping member also having a plurality of slot-like recesses defined in the tissue grasping member adjacent to the plurality of barbs along the side edge.

7. The gripping assembly of claim 1, wherein: The flexible member also includes a cover surrounding at least a portion of the arm.

8. The gripping assembly of claim 1, wherein: The tissue grasping member also includes a cover.

9. The gripping assembly of claim 1, wherein: The tissue grasping member is also attached to the arm by welding or soldering.

10. The gripping assembly of claim 1, wherein: The arm includes at least one bending feature made of a shape memory material and configured to enable movement of the arm.

11. The gripping assembly of claim 1 , wherein: The tissue grasping surface also includes a hole for the connection of an actuator wire.

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