Clip delivery catheter with helical multi-lumen extrudate for improved gripper actuation and methods of making and using same

Abstract

An interventional tool includes a delivery catheter defining a central lumen and a plurality of peripheral lumens, at least one of the plurality of peripheral lumens defining a helical path along a portion of the delivery catheter, and at least one line disposed within the at least one of the plurality of peripheral lumens, the at least one line is configured to actuate the medical device.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Provisional Application No. 63 / 484,771, filed on February 14, 2023, the contents of which are incorporated herein by reference in their entirety as if fully set forth. Background Art

[0003] Mitral valve regurgitation can be characterized by retrograde flow from the left ventricle of the heart through the damaged mitral valve into the left atrium. During the normal cycle of heart contraction (systole), the mitral valve ideally acts as a one-way valve to prevent oxygenated blood from flowing back into the left atrium. In this way, oxygenated blood is pumped into the aorta through the aortic valve. Valvular regurgitation can significantly reduce the heart's pumping efficiency, putting patients at risk for severe, progressive heart failure.

[0004] Mitral regurgitation can be caused by a number of different mechanical defects in the mitral valve or the left ventricular wall. The valve leaflets, the chordae tendineae that connect the leaflets to the papillary muscles, the papillary muscles, or the left ventricular wall may be damaged or otherwise malfunction. Often, the annulus may be damaged, dilated, or weakened, limiting the ability of the mitral valve to close adequately under the high pressures of the left ventricle.

[0005] Common treatments for mitral valve regurgitation rely on valve replacement or repair, including reshaping of the leaflets and annulus, the latter of which is often referred to as annuloplasty. Another mitral valve repair technique relies on suturing together adjacent segments of opposing valve leaflets, known as the "bow tie" or "edge to edge" technique. While all of these techniques are very effective, they typically rely on open heart surgery, i.e., opening the patient's chest (usually through a sternotomy) and then placing the patient on cardiopulmonary bypass. The need to open the chest and place the patient on bypass is invasive and has an associated high mortality and morbidity rate.

[0006] Alternatively, mitral valve regurgitation can be corrected by delivering an implant through a catheter that promotes complete closure of the mitral valve during each systolic cycle. Transcatheter delivery can be a complex procedure that requires close attention and much input and manipulation from the implanter, interventionist, or physician (who will be collectively referred to as the term "physician" in the remainder of this disclosure). In some cases, the orientation of the delivery catheter can affect the ability to manipulate the mitral valve repair implant. Specifically, the shape of the delivery catheter during implantation can affect how the repair implant is actuated. This is particularly true for repair implants that rely on a clamp for operation. Summary of the Invention

[0007] In some examples, the interventional tool includes a delivery catheter defining a central lumen and a plurality of peripheral lumens, at least one of the plurality of peripheral lumens defining a spiral path along a portion of the delivery catheter, and at least one tubing disposed within at least one of the plurality of peripheral lumens, the at least one tubing configured to actuate a medical device.

[0008] In some examples, a method of actuating a medical device includes providing an interventional tool comprising a delivery catheter defining a central lumen and a plurality of peripheral lumens, at least one of the plurality of peripheral lumens defining a spiral path along a portion of the delivery catheter, at least one wire disposed within at least one of the plurality of peripheral lumens, and pulling the at least one wire to actuate the medical device. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 The left ventricle and left atrium of the heart are shown during systole.

[0010] Figure 2A The free edges of the blades in normal coaptation are shown, and Figure 2B The free edge is shown in the reverse flow joint.

[0011] Figures 3A to 3C Grasping of the blade with the fixation device, flipping of the distal element of the fixation device, and removal of the fixation device are illustrated respectively.

[0012] Figure 4 The position of the fixing device relative to the blade in the desired orientation is illustrated.

[0013] Figure 5 、 Figures 6A to 6B and Figure 7 Embodiments of the securing device are illustrated in various positions.

[0014] Figures 8A to 8B An embodiment of a fixation device is illustrated in which some or all of the components are molded as one part.

[0015] Figure 9 Another embodiment of the fixing device of the present disclosure is illustrated.

[0016] FIG. 10A to FIG. 10B 、 Figures 11A to 11B 、 FIG. 12A to FIG. 12B 、 13A to 13B 、 Figures 14 to 16 Embodiments of the fixation device are illustrated in various possible positions during introduction and placement of the device within the body to perform a therapeutic procedure.

[0017] 17A to 17C The illustrations show a covering on a stationary device with the device in various positions.

[0018] Figure 18 A delivery catheter coupled to a fixation device is shown.

[0019] Figures 19A to 19B Schematic diagram of a multi-lumen extrusion for a delivery catheter and its axial cross-section.

[0020] Figure 20 A multi-lumen extrusion is shown disposed along the entirety of a delivery catheter according to a first embodiment.

[0021] Figure 21 A multi-lumen extrusion is shown disposed along only a portion of a delivery catheter according to a second embodiment. DETAILED DESCRIPTION

[0022] When used in conjunction with a delivery device for delivering a device into a patient, the terms "proximal" and "distal" should be considered relative to the user of the delivery device. "Proximal" should be understood as relatively close to the user, while "distal" should be understood as relatively away from the user. When used in conjunction with a fixation device, the terms "proximal" and "distal" should be considered relative to the treatment site. "Proximal" should be understood as relatively close to the treatment site, while "distal" should be understood as relatively away from the treatment site. As used herein, the terms "substantially," "generally," "approximately," and "about" are intended to indicate that slight deviations from the absolute values ​​are also included within the scope of the terms so modified. Throughout this disclosure, the mitral valve is described in an illustrative manner. A clip can be similarly used to treat the tricuspid valve to reduce regurgitation on the right side of the heart. This method of tricuspid valve repair is particularly hampered by poor imaging due to the unfavorable anatomy of the heart relative to the esophagus. A transesophageal echocardiographic probe can advantageously be pressed toward the left side of the heart to obtain adequate imaging of the mitral valve. This is not the case with the tricuspid valve, and imaging is generally poorer. For this reason, the sensor can provide a particular benefit to the user in gaining confidence in the placement of the clip during tricuspid valve repair surgery. Thus, the present disclosure is not limited to mitral valve clips, but similar technology can also be used to ensure proper attachment of other clips, valves, or other devices in cardiac and other medical applications.

[0023] I. Cardiac Physiology

[0024] During systole, the left ventricle (LV) of a normal heart is Figure 1As shown. The left ventricle LV is contracting and blood is flowing outward through the aortic valve AV in the direction of the arrow. Backflow or "regurgitation" of blood through the mitral valve MV is prevented because the mitral valve is configured as a "check valve" that prevents backflow when the pressure in the left ventricle is higher than the pressure in the left atrium LA. The mitral valve MV includes a pair of leaflets having free edges FE that meet evenly to close, as shown. Figure 1 As shown in Figure 2 . The opposite ends of the leaflets LF are attached to the surrounding cardiac structures along an annular region known as the annulus AN. The free edges FE of the leaflets LF are fixed to the lower portion of the left ventricle LV by chordae tendineae CT (hereinafter referred to as chordae tendineae), which comprise a plurality of branching chordae tendineae fixed to the lower surface of each valve leaflet LF. The chordae tendineae CT, in turn, attach to the papillary muscles PM, which extend upward from the lower portion of the left ventricle and the interventricular septum IVS.

[0025] Many structural defects in the heart can cause mitral valve regurgitation. Regurgitation occurs when the valve leaflets do not close properly, causing leakage from the ventricles to the atria. Figure 2A As shown, the free edges of the front and rear blades generally meet along a junction line C. Figure 2B An example of a defect that causes regurgitation is shown in . Here, enlargement of the heart causes the mitral annulus to become enlarged, making it impossible for the free edges FE to meet during systole. This results in a gap G, which causes blood to leak through the valve during ventricular contraction. Broken or stretched chordae tendineae can also cause valve leaflets to prolapse because insufficient tension is transmitted to the leaflets via the chordae tendineae. While the other leaflet maintains its normal contour, the two valve leaflets cannot meet properly and leakage from the left ventricle to the left atrium will occur. This type of regurgitation can also occur in patients with ischemic heart disease, in whom the left ventricle cannot contract sufficiently to achieve proper closure.

[0026] II. General Overview

[0027] The present disclosure provides methods and devices for grasping, approximating, and securing tissue (e.g., valve leaflets) to treat heart valve regurgitation, particularly mitral valve regurgitation. The present disclosure also provides features that allow the device to be repositioned and removed when desired, particularly in areas where anatomical features (e.g., chordae tendineae) may hinder removal. Such removal allows the surgeon to reapproach the valve in a new manner, if desired.

[0028] The gripping will preferably be non-invasive, thereby providing a number of benefits. Non-invasive means that the devices and methods of the present disclosure can be applied to the valve leaflets and then removed without causing any significant clinical damage to the leaflet structure or function. The leaflets and valve continue to perform essentially the same function as before the application of the present disclosure. Therefore, some slight penetration or denting of the leaflets may occur using the present disclosure, while still meeting the definition of "non-invasive". This enables the devices of the present disclosure to be applied to diseased valves and, if desired, the valve to be removed or repositioned without negatively affecting valve function. In addition, it should be understood that in some cases it may be necessary or desirable to puncture or otherwise permanently affect the leaflets during gripping, fixation, or both. In some of these cases, gripping and fixation can be accomplished by a single device. Although many embodiments are provided to achieve these results, a general overview of the basic features will be presented herein. These features are not intended to limit the scope of the present disclosure and are presented for the purpose of providing a basis for the description of the various embodiments presented later in this application.

[0029] The devices and methods of the present disclosure rely on the use of an interventional tool that is positioned proximate to the desired treatment site and used to grasp the target tissue. In intravascular applications, the interventional tool is typically an interventional catheter. In surgical applications, the interventional tool is typically an interventional instrument. In a preferred embodiment, fixation of the grasped tissue is achieved by maintaining the grip with a portion of the interventional tool that remains as an implant. While the present disclosure may have a variety of applications for tissue approximation and fixation throughout the human body, it is particularly well suited for the repair of valves, particularly heart valves such as the mitral valve. References Figure 3A , an interventional tool 10 having a delivery device (e.g., shaft 12) and a fixation device 14 is shown having approached the mitral valve MV from the atrial side and grasped the leaflets LF. As described above, the mitral valve can be approached intraoperatively or by using endovascular techniques and can be approached by a retrograde approach through the ventricle or by an antegrade approach through the atrium. For illustration purposes, an antegrade approach is described.

[0030] The fixation device 14 is releasably attached at its distal end to the shaft 12 of the interventional tool 10. When describing the devices of the present disclosure herein, "proximal" shall mean the direction toward the end of the device to be manipulated by a user outside the patient's body, and "distal" shall mean the direction toward the working end of the device positioned at the treatment site and away from the user. With respect to the mitral valve, proximal shall mean the atrial or upstream side of the valve leaflets, and distal shall mean the ventricular or downstream side of the valve leaflets.

[0031] The fixation device 14 generally includes a proximal element 16 (or clamping element) and a distal element 18 (or fixation element) that project radially outward and, as shown, can be positioned on opposite sides of the blades LF so as to capture or retain the blades therebetween. The proximal element 16 is preferably constructed of cobalt-chromium alloy, nitinol, or stainless steel, and the distal element 18 is preferably constructed of cobalt-chromium alloy or stainless steel, although any suitable material may be used. The fixation device 14 can be coupled to the shaft 12 by a coupling mechanism 17. The coupling mechanism 17 allows the fixation device 14 to be detached and left as an implant to hold the blades together in an engaged position.

[0032] In some cases, it may be desirable to reposition or remove the fixation device 14 after the proximal elements 16, the distal elements 18, or both have been deployed to capture the leaflets LF. Such repositioning or removal may be desirable for a variety of reasons, such as reapproximating the valve in an attempt to achieve better valve function, better optimal positioning of the device 14 on the leaflets, better gripping of the leaflets, disentangling the device 14 from surrounding tissue such as chordae tendineae, exchanging the device 14 for a device having a different design, or aborting the fixation process, to name a few. To facilitate repositioning or removal of the fixation device 14, the distal elements 18 are releasable and, optionally, flippable to a configuration suitable for withdrawing the device 14 from the valve without tangling or interfering with or damaging the chordae tendineae, leaflets, or other tissue. Figure 3B The figure shows a flip, wherein the distal element 18 can be moved in the direction of arrow 40 to the flip position. Likewise, the proximal element 16 can be raised if necessary. In the flip position, the device 14 can be repositioned to the desired orientation, wherein the distal element can then be restored to a gripping position against the blades, as shown. Figure 3A Alternatively, as Figure 3C As shown, the fixation device 14 can be withdrawn from the leaflets (indicated by arrow 42). This inversion reduces trauma to the leaflets and minimizes any entanglement of the device with surrounding tissue. Once the device 14 has been withdrawn through the valve leaflets, the proximal and distal elements can be moved to a closed position or a configuration suitable for removal from the body or for reinsertion through the mitral valve.

[0033] Figure 4 The position of the fixation device 14 relative to the leaflets LF in a desired orientation is shown. This is a short axis view of the mitral valve MV from the atrial side, and therefore the proximal element 16 is shown in solid lines and the distal element 18 is shown in dashed lines. The proximal element 16 and the distal element 18 are positioned substantially perpendicular to the coaptation line C. The device 14 can be moved to the regurgitant position approximately along the coaptation line. The leaflets LF are held in place so that during diastole (e.g. Figure 4The leaflets LF are held in position between the elements 16, 18 surrounded by the opening O created by the diastolic pressure gradient (as shown). Advantageously, the leaflets LF are joined so that their proximal or upstream surfaces face each other in a vertical orientation, parallel to the direction of blood flow through the mitral valve MV. The upstream surfaces can be brought together so as to touch each other, or can be held slightly apart, but will preferably be held in a vertical orientation in which the upstream surfaces face each other at the junction. This simulates the double orifice geometry of a standard surgical butterfly tie repair. Color Doppler echo will show whether the regurgitation of the valve has been reduced. If the resulting mitral flow pattern is satisfactory, the leaflets can be fixed together in this orientation. If the resulting color Doppler image shows insufficient improvement in mitral valve regurgitation, the interventional tool 10 can be repositioned. This can be repeated until the optimal result is produced, in which case the leaflets LF remain in place.

[0034] Once the blades are engaged in the desired arrangement, the fixation device 14 is then detached from the shaft 12 and left as an implant to hold the blades together in the engaged position. As previously described, the fixation device 14 is coupled to the shaft 12 by a coupling mechanism 17. Other coupling mechanisms are described in U.S. Patent No. 9,510,829, which is incorporated herein by reference in its entirety as if fully set forth herein.

[0035] III. Fixed Equipment

[0036] A. Introduction and placement of fixed equipment

[0037] The fixation device 14 is delivered to the valve or desired tissue using a delivery device. The delivery device can be rigid or flexible, depending on the application. For intravascular applications, the delivery device comprises a flexible delivery catheter, which will be described in a later section. Typically, however, such a catheter comprises a shaft having a proximal end and a distal end, and a fixation device releasably attached to its distal end. The shaft is typically elongated and flexible, suitable for intravascular introduction. Alternatively, the delivery device may comprise a shorter and less flexible interventional instrument that can be used for transthoracic surgical introduction through the heart wall, although some flexibility and minimal profile are generally desired. As Figure 3A As shown, the fixation device is releasably coupled to the delivery device. The fixation device can take a variety of forms, several examples of which will be described herein.

[0038] Figure 5 、 Figures 6A to 6B and Figure 7 Embodiments of the fixation device 14 are illustrated in various positions or configurations. Figure 5The fixation device 14 is illustrated in a closed configuration for delivery through the vasculature of a patient, and in this example, through the mitral valve. The fixation device 14 includes a coupling member 19 that allows the fixation device 14 to be detached for implantation. In this example, the coupling member 19 is shown as including a lower shaft 22 and a mating surface 24, and thus the coupling member 19 will function similarly to that described above. The fixation device 14 also includes a pair of opposing distal elements 18, each distal element 18 having an engagement surface 50 that faces inwardly toward the opposing distal element 18 in the closed configuration. The distal elements 18 preferably include elongated arms 53, each arm having a proximal end 52 rotatably connected to the coupling member 19 and a free end 54. Suitable connections for the arms 53 to the coupling member 19 include pins, living hinges, or other known rotational connection mechanisms. Figure 5 In the closed configuration, free ends 54 point in a first direction such that arms 53 and engagement surface 50 are nearly parallel to each other and to axis 21, and are preferably angled slightly inwardly toward each other. In a preferred embodiment, arms 53 can be closed when no tissue is present between arms 53 until free ends 54 either contact each other or engage with shaft 12 when fixation device 14 is attached to shaft 12, thereby minimizing the profile of fixation device 14 for passage through a delivery device.

[0039] Figures 6A to 6B The fixation device 14 is illustrated in an open position wherein the engagement surfaces 50 are arranged to separate at a separation angle 56, wherein the separation angle 56 is typically up to about 180 degrees, preferably up to 90 to 180 degrees, and wherein the arms 53 are arranged generally symmetrically relative to the axis 21. The arms 53 can be moved to the open position by various actuation mechanisms. For example, a plunger or actuator rod can be advanced through the coupling member 19, as indicated by arrow 62, to engage a spring or spring-loaded actuation mechanism 58 attached to the distal element 18. By applying a force against the actuation mechanism 58, the distal element 18 is rotated relative to the coupling member 19. The distal element 18 can be maintained in the open position by the actuator rod against the resistance provided by the spring of the actuation mechanism 58, and when the distal elements 18 are separated by less than 180 degrees, the spring of the actuation mechanism 58 pulls the distal element 18 toward Figure 5 The spring loading of the actuating mechanism 58 resists the outward movement of the actuating mechanism 58 and pushes the device 14 toward the closed position.

[0040] In this embodiment, the proximal element 16 comprises a resilient annular wire form which is outwardly biased and attached to the coupling member 19 so as to be biased to Figure 6B18. The arms 53 may be in the open position shown, but may be rotationally movable inwardly when the arms 53 are closed. The wire forms may be sufficiently flexible to be rigidly attached to the coupling member 19 and resiliently deflectable inwardly, or they may be attached by a rotational coupling (e.g., a pin or living hinge). In use, the leaf LF is positioned between the proximal element 16 and the distal element 18. Once the leaf LF is positioned between the proximal element 16 and the distal element 18, the distal element 18 may be closed, thereby compressing the leaf between the engagement surface 50 and the proximal element 18. Depending on the thickness of the leaf, the arrangement of the leaf, the location of the fixation device on the leaf, and other factors, the arms 53 may be held in place. Figures 6A to 6B Open position, move to Figure 5 The fully closed position of the fixing device 14 or any of the various positions therebetween is provided to engage the leaves LF and hold them in the desired position with the desired degree of force. In any case, after being disengaged from the delivery catheter, the fixing device 14 will remain in place as an implant.

[0041] In some cases, as previously described, it may be desirable to reopen the fixation device 14 after initial placement. To reopen the device 14, the actuator rod may be re-advanced or reinserted through the coupling member 19 and re-advanced to press against the actuation mechanism 58, as previously described. Figure 6A 6. This advancement, as indicated by arrow 62 in FIG. 6 , applies force against the actuation mechanism 58 in the manner described above, thereby moving the arms 53 outward to release the force against the blades and move the engagement surface 50 away from the proximal element 16. The blades are then free to move relative to the fixation device 14. The fixation device 14 can then be repositioned as desired, and the actuator rod retracted to reclose the distal element 18, thereby engaging the blades.

[0042] In some cases, after initial insertion through the valve, it may be further desirable to withdraw the fixation device 14 through the valve or completely from the patient. Figure 5 、 Figures 6A to 6B and Figure 7 If this is attempted with the arms 53 in the closed or open positions shown, there is a risk that the arms 53 may interfere with the chordae tendineae, laminae or other tissue or become entangled with such parts. To avoid this, the fixation element 14 is preferably adapted to flip the arms 53 so that the free ends 54 point in a second direction that is opposite to the first direction that the free ends 54 point in when in the closed position, each arm 53 forming an obtuse angle with respect to the axis 21, as shown. Figure 7As shown. Arm 53 can be rotated so that engagement surface 50 is disposed at a separation angle 56 of up to 360 degrees, and preferably at least up to 270 degrees. This can be achieved as described above by applying a force against actuation mechanism 58 using a push rod or plunger extending through coupling member 19. In this embodiment, once distal element 18 has been rotated beyond 180 degrees, the spring loading of actuation mechanism 58 biases distal element 18 toward the flipped position. The spring loading of actuation mechanism 58 resists outward movement of actuation mechanism 58 and forces device 14 into the flipped position.

[0043] With the arms 53 in the flipped position, the engagement surface 50 provides an atraumatic surface for tissue deflection as the fixation device is withdrawn. This allows the device to be retracted through the annulus without risk of damaging the valve and other tissue. In some cases, once the fixation device 14 has been pulled back through the valve, it will be desirable to return the device to the closed position to withdraw the device from the body (either through the vasculature or through a surgical opening).

[0044] Figure 5 、 Figure 6A 、 Figure 6B and Figure 7 The embodiment shown in FIG is assembled from separate components that are composed of biocompatible materials. These components can be formed from the same or different materials, including but not limited to stainless steel or other metals, Nitinol, titanium, tantalum, metal alloys, or polymers. Additionally, some or all of these components can be made of bioresorbable materials that will be absorbed by the surrounding tissue or will dissolve into the bloodstream after implantation. It has been found that in mitral valve repair applications, the fixation devices of the present disclosure are completely surrounded by tissue within a few months of implantation, after which the devices can dissolve or be absorbed without negatively impacting the repair.

[0045] In another embodiment, Figures 8A to 8B As shown, some or all of the components may be molded as one part. Here, the coupling member 19, distal element 18 and actuation mechanism 58 of the fixation device 14 are all molded from a polymer material as one movable piece. Figure 8A The fixation device 14 is shown in an open position. Advancement of the actuator rod 64 causes the distal element 18 to rotate relative to the coupling member 19, either through a living hinge or through elastic deformation of the plastic at the connection point between the element 18 and the coupling member 19. Typically, this connection point includes a thinner polymer section to facilitate this bending. Similarly, the actuation mechanism 58 is coupled to the distal element 18 in the same manner. Figure 8B The securing device 14 is shown in an inverted position.

[0046] Figure 9Another embodiment of the fixation device 14 is shown. Here, the fixation device 14 is shown as being coupled to the shaft 12 to form the interventional tool 10. The fixation device 14 includes a coupling member 19 and a pair of opposing distal elements 18. The distal elements 18 include elongated arms 53, each having a proximal end 52 rotatably connected to the coupling member 19 and a free end 54. The free ends 54 have a circular shape to minimize interference and trauma to surrounding tissue structures. Preferably, each free end 54 defines a curvature about two axes, one of which is an axis 66 perpendicular to the longitudinal axis of the arm 53. Thus, the engagement surface 50 has a cup-shaped or concave shape to allow the surface area to contact the tissue and assist in grasping and retaining the valve leaflets. This further allows the arms 53 to nest around the shaft 12 in a closed position to minimize the profile of the device. Preferably, the arms 53 are at least partially cupped or curved inwardly about their longitudinal axis 66. Furthermore, each free end 54 preferably defines a curvature about an axis 67 that is perpendicular to axis 66 or the longitudinal axis of arm 53. This curvature is a reverse curvature along the distal-most portion of free end 54. Likewise, the longitudinal edges of free end 54 may flare outwardly. Both the reverse curvature and the flaring minimize trauma to tissue engaged therewith.

[0047] In a preferred embodiment suitable for mitral valve repair, the lateral width across the engagement surface 50 (which determines the width of the engaged tissue) is at least about 2 mm, typically 3 mm to 10 mm, and preferably about 4 mm to 6 mm. In some cases, a wider engagement is desired, where the engagement surface 50 is larger (e.g., about 2 cm), or multiple fixation devices are used adjacent to each other. The arm 53 and the engagement surface 50 are configured to engage a length of tissue of about 4 mm to 10 mm (preferably about 6 mm to 8 mm) along the longitudinal axis of the arm 53. The arm 53 further includes a plurality of openings to enhance grip and promote tissue ingrowth after implantation.

[0048] The valve leaflets are clamped between the distal element 18 and the proximal element 16. In some embodiments, the proximal element 16 is flexible, resilient, and extends from the coupling member 19 in a cantilevered manner. The proximal element is preferably resiliently biased toward the distal element. Each proximal element 16 is shaped and positioned to be at least partially recessed within the concave surface of the distal element 18 when no tissue is present. When the fixation device 14 is in the open position, the proximal elements 16 are shaped so that each proximal element 16 is separated from the engagement surface 50 near the proximal end 52 of the arm 53 and is inclined toward the engagement surface 50 near the free end 54, with the free end of the proximal element contacting the engagement surface 50, as shown. Figure 9 This shape of the proximal element 16 accommodates valve leaflets or other tissues of varying thicknesses.

[0049] The proximal element 16 includes a plurality of openings 63 and scalloped side edges 61 to increase grip on tissue. The proximal element 16 may optionally include a friction attachment, friction feature, or grip enhancement element to help grasp and / or retain the blade. In a preferred embodiment, the friction attachment includes a barb 60 having a tapered tip extending toward the engagement surface 50. It will be appreciated that any suitable friction attachment may be used, such as prongs, windings, strips, barbs, grooves, channels, bumps, surface roughening, sintering, high friction pads, coverings, coatings, or combinations thereof.

[0050] Optionally, magnets may be present in the proximal element and / or the distal element. It will be appreciated that the mating surfaces will be made of or will include materials having opposite magnetic charges to cause attraction by magnetic force. For example, the proximal element and the distal element may each include magnetic materials of opposite charge so that the tissue is held under constant compression between the proximal element and the distal element to promote faster healing and ingrowth of the tissue. In addition, magnetic force can be used to bias the proximal element toward the distal element as a supplementary or alternative means to bias the proximal element 16 toward the distal element 18. This can facilitate the deployment of the proximal element 16. In another example, each of the distal elements 18 includes magnetic materials of opposite charge so that the tissue positioned between the distal elements 18 is held between the distal elements 18 by magnetic force.

[0051] The proximal element 16 can be covered with a fabric or other flexible material as described below to enhance post-implantation grip and tissue ingrowth. Preferably, when a fabric or covering is used in combination with barbs or other friction features, these features will protrude through such fabric or other covering to contact any tissue engaged by the proximal element 16.

[0052] In an exemplary embodiment, the proximal element 16 is formed from a metal sheet of a spring-like material using a stamping operation that forms the opening 63, the scalloped edge 61, and the barbs 60. Alternatively, the proximal element 16 can be constructed of a spring-like material, or molded from a biocompatible polymer. It should be noted that while some types of friction attachments that may be used in the present disclosure may permanently alter or cause some trauma to the tissue engaged thereby, in preferred embodiments, the friction attachments will be non-traumatic and will not injure or otherwise affect the tissue in a clinically significant manner. For example, in the case of the barbs 60, it has been demonstrated that after the mitral valve leaflets are engaged by the fixation device 14, if the device is later removed during surgery, the barbs 60 do not leave significant permanent scarring or other damage to the leaflet tissue and are therefore considered non-traumatic.

[0053] The fixation device 14 also includes an actuation mechanism 58. In this embodiment, the actuation mechanism 58 includes two linkage members or legs 68, each leg 68 having a first end 70 rotatably coupled to one of the distal elements 18 at a riveted joint 76 and a second end 72 rotatably coupled to a stud 74. The legs 68 are preferably constructed of a rigid or semi-rigid metal or polymer (e.g., ), however, any suitable material may be used. Although in the illustrated embodiment, the two legs 68 are pinned to the stud 74 by a single rivet 78, it will be appreciated that each leg 68 may be individually attached to the stud 74 by a separate rivet or pin. The stud 74 may be coupled to an actuator rod 64 (not shown) that extends through the shaft 12 and may be axially extended and retracted to move the stud 74 and, thereby, the legs 68 that rotate the distal element 18 between the closed position, the open position, and the flipped position. Likewise, the securing of the stud 74 holds the legs 68 in place and, thereby, the distal element 18 in the desired position. The stud 74 may also be locked in place by a locking feature, which will be further described in a later section.

[0054] In any embodiment of the fixation device 14 disclosed herein, it may be desirable to provide some mobility or flexibility in the distal element 18 and / or the proximal element 16 when in the closed position so that these elements can move or flex as the valve leaflets open or close. This provides shock absorption, thereby reducing the forces on the leaflets and minimizing the possibility of tearing or other trauma to the leaflets. This mobility or flexibility can be provided by using a flexible, resilient metal or polymer of appropriate thickness to construct the distal element 18. In addition, the locking mechanism of the fixation device (described below) can be constructed of a flexible material so that some slight movement of the proximal and distal elements is allowed even when locked. Further, the distal element 18 can be connected to the coupling mechanism 19 or to the actuation mechanism 58 by a mechanism that biases the distal element to the closed position (inward) but allows the arms to open slightly in response to the force applied by the leaflets. For example, rather than being pinned to a single point, these components can be pinned via a slot that allows the pin to translate a small amount in response to the force resisting the arm. A spring is used to bias the pinned component toward one end of the slot.

[0055] FIG. 10A to FIG. 10B 、 Figures 11A to 11B 、 FIG. 12A to FIG. 12B 、 13A to 13B ,as well as Figures 14 to 16 The device 14 is shown in various possible positions during its introduction and placement into the human body to perform a therapeutic procedure. Figure 9 An embodiment of the fixing device 14. Figure 10AAn embodiment of an interventional tool 10 is illustrated being delivered through a catheter 86. It will be appreciated that the interventional tool 10 can take the form of a catheter, and similarly, the catheter 86 can take the form of a guide catheter or sheath. However, in this example, the terms interventional tool 10 and catheter 86 will be used. 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. Figure 10B A larger view shows the Figure 10A . In the closed position, the opposing pair of 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 or concave shape so that the arms 53 together surround the shaft 12 and optionally contact each other on opposite sides of the shaft. This provides a low profile for the fixation device 14 that is easy to pass through the catheter 86 and through any anatomical structure (e.g., the mitral valve). In addition, Figure 10B Further included is an actuation mechanism 58. In this embodiment, the actuation mechanism 58 includes two legs 68, each of which is movably coupled to a base 69. The base 69 is coupled to an actuator rod 64, which extends through the shaft 12 and is used to manipulate the fixation device 14. In some embodiments, the actuator rod 64 is directly attached to the actuation mechanism 58, and in particular to the base 69. However, the actuator rod 64 can alternatively be attached to a stud 74, which in turn is attached to the base 69. In some embodiments, the stud 74 is threaded, such that the actuator rod 64 is attached to the stud 74 via a screw-like action. However, the rod 64 and the stud 74 can be coupled by any releasable mechanism to allow the fixation device 14 to be detached from the shaft 12.

[0056] Figures 11A to 11B The fixation device 14 is shown in the open position. In the open position, the distal element 18 is rotated so that the engagement surface 50 faces in a first direction. Distal advancement of the stud 74 relative to the coupling member 19, via the action of the actuator rod 64, applies a force to the distal element 18, causing the distal element 18 to begin rotating about the joint 76 due to its freedom of movement in this direction. This radially outward rotation and movement of the distal element 18 causes the legs 68 to rotate about the joint 80, causing them to point slightly outward. The stud 74 can be advanced to any desired distance associated with the desired separation of the distal element 18. In the open position, the engagement surfaces 50 are arranged at an acute angle relative to the shaft 12, preferably at an angle between 90 and 180 degrees relative to each other. In one embodiment, in the open position, the span between the free ends 54 of the arms 53 is approximately 10 to 20 mm, typically approximately 12 to 18 mm, and preferably approximately 14 to 16 mm.

[0057] The proximal element 16 is generally biased outwardly toward the arm 53. The proximal element 16 can be moved inwardly toward the shaft 12 and is held against the shaft 12 by means of a proximal element line 90, which can be in the form of a suture, cable, nitinol line, rod, wire, polymer line, or other suitable structure. The proximal element line 90 can be connected to the proximal element 16 in various ways by passing the line 90 through the proximal element 16. When the proximal element 16 has an annular shape (e.g., Figure 11A As shown in FIG), the line 90 can pass through the ring and return. Figure 11B ), the tubing 90 may be passed through one or more openings 63 in the element 16. Additionally, a wire loop 48 may be present on the proximal element 16 (also on the Figure 11B ) through which the proximal element line 90 can pass and fold back. Such a wire loop 48 is useful for reducing friction on the proximal element line 90, or is also useful when the proximal element 16 is solid or does not have other rings or openings through which the proximal element line 90 can be attached. The proximal element line 90 can be attached to the proximal element 16 by a detachable device that will allow a single line 90 to be attached to the proximal element 16 without folding back, and will allow a single line 90 to be directly removed from the proximal element 16 when desired. Examples of such detachable devices include hooks, snares, clips, or breakable couplings, to name a few. By applying sufficient tension to the proximal element line 90, the detachable device can be removed from the proximal element 16 (e.g., by breaking a coupling). Other mechanisms for removal can also be used. Similarly, the locking line 92 can be attached to and removed from the locking mechanism by a similar detachable device.

[0058] In the open position, the fixation device 14 can engage tissue to be accessed or treated. Figure 9 to Figure 1 The embodiment illustrated in FIG1 is suitable for repairing the mitral valve using an antegrade approach from the left atrium. The interventional tool 10 is advanced through the mitral valve from the left atrium to the left ventricle. The distal element 18 is oriented perpendicular to the line of coaptation and then positioned so that the engagement surface 50 contacts the ventricular surface of the valve leaflets, thereby gripping the leaflets. The proximal element 16 is retained on the atrial side of the valve leaflets so that the leaflets are positioned between the proximal and distal elements. In this embodiment, the proximal element 16 has frictional attachments, such as barbs 60, that point toward the distal element 18. However, at this time, neither the proximal element 16 nor the barbs 60 contact the leaflets.

[0059] The interventional tool 10 can be repeatedly manipulated to reposition the fixation device 14 so that the blades are properly contacted or gripped at the desired location. The repositioning is achieved with the fixation device in the open position. In some cases, regurgitation can also be checked with the device 14 in the open position. If regurgitation is not satisfactorily reduced, the device can be repositioned and regurgitation checked again until the desired result is achieved.

[0060] It may also be desirable to flip the fixation device 14 over to facilitate repositioning or removal of the fixation device 14 . FIG. 12A to FIG. 12B The fixation device 14 is shown in an inverted position. By further advancing the stud 74 relative to the coupling member 19, the distal element 18 is further rotated, such that the engagement surface 50 faces outward and the free end 54 points distally, with each arm 53 forming an obtuse angle relative to the shaft 12. The angle between the arms 53 is preferably in the range of approximately 270 to 360 degrees. Further advancement of the stud 74 causes the distal element 18 to further rotate about the joint 76. This radially outward rotation and movement of the distal element 18 causes the legs 68 to rotate about the joint 80, returning the legs 68 to their initial position, substantially parallel to one another. The stud 74 can be advanced to any desired distance associated with the desired inversion of the distal element 18. Preferably, in the fully inverted position, the span between the free ends 54 is no greater than approximately 20 mm, typically less than approximately 16 mm, and preferably approximately 12 to 14 mm. In this illustration, the proximal element 16 is held in place against the shaft 12 by applying tension to the proximal element tubing 90. Thus, a relatively large space can be created between elements 16, 18 for repositioning. In addition, the inverted position allows the fixation device 14 to be withdrawn through the valve while minimizing trauma to the leaflets. The engagement surface 50 provides an atraumatic surface for deflecting tissue as the fixation device is retracted proximally. It should be further noted that 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 snag or tear tissue as the fixation device is withdrawn.

[0061] Once the fixation device 14 has been positioned against the valve leaflets in the desired location, the leaflets may be captured between the proximal and distal elements 16 , 18 . 13A to 13B The fixing device 14 is shown in this position. Here, the proximal element 16 is lowered towards the engagement surface 50 so that the blade is held therebetween. Figure 13B In FIG, the proximal element 16 is shown as including barbs 60 that can be used to provide atraumatic gripping of the blades. Alternatively, larger, sharper barbs or other penetrating structures can be used to pierce the blades to more actively help hold them in place. This position is similar to Figures 11A to 11BHowever, by releasing the tension on the proximal element lines 90 to compress the leaflet tissue therebetween, the proximal element 16 is now lowered toward the arms 53. At any time, if the regurgitation is not sufficiently reduced, the proximal element 16 can be raised and the distal element 18 can be adjusted or flipped to reposition the fixation device 14.

[0062] After the blades have been captured between the proximal and distal elements 16, 18 in the desired arrangement, the distal element 18 can be locked to hold the blades in that position, or the fixation device 14 can be returned to or toward the closed position. Such locking will be described in a later section. Figure 14 The fixation device 14 is shown in a closed position, with the blades (not shown) captured and engaged. This is achieved by retracting the stud 74 proximally relative to the coupling member 19, causing the legs 68 of the actuating mechanism 58 to apply an upward force to the distal element 18, which in turn rotates the distal element 18 so that the engagement surfaces 50 once again face each other. The released proximal element 16, which is biased outwardly toward the distal element 18, is simultaneously pushed inwardly by the distal element 18. The fixation device 14 can then be locked to maintain the blades in this closed position, as described below.

[0063] like Figure 15 As shown, the securing device 14 may then be released from the shaft 12. As described above, the securing device 14 may be releasably coupled to the shaft 12 by the coupling member 19. Figure 15 The diagram illustrates a coupling structure, i.e., a portion of the shaft 12 to which the coupling member 19 of the fixation device 14 is attached. As shown, the proximal element line 90 can remain attached to the proximal element 16 after being detached from the shaft 12 to serve as a tether to keep the fixation device 14 connected to the catheter 86. Alternatively, a separate tether connected between the shaft 12 and the fixation device 14 can be used specifically for this purpose while the proximal element line 90 is removed. In any case, the repair of the blade or tissue can be observed by non-invasive visualization techniques (e.g., echocardiography) to ensure the desired results. If the repair is not desired, the fixation device 14 can be retrieved using the tether or proximal element line 90 so that the coupling member 19 can be reconnected to the shaft 12.

[0064] In an exemplary embodiment, the proximal element lines 90 are elongated flexible wires, cables, threads, sutures, or threads that extend through the shaft 12, loop through the proximal element 16, and extend rearwardly through the shaft 12 to its proximal end. When removal is desired, one end of each line can be released at the proximal end of the shaft 12, and the other end pulled to pull the free end of the line distally through the shaft 12 and through the proximal element 16, thereby releasing the fixation device.

[0065] Figure 16The released fixation device 14 is shown in a closed position. As shown, the coupling member 19 remains separated from the shaft 12 of the interventional tool 10 and the proximal element 16 is deployed so that tissue (not shown) can reside between the proximal element 16 and the distal element 18.

[0066] While the above-described embodiments of the present disclosure utilize a push-to-open mechanism and a pull-to-close mechanism to open and close the distal element 18, it should be understood that a pull-to-open mechanism and a push-to-close mechanism are equally possible. For example, the distal element 18 can be coupled to the stud 74 at its proximal end instead of to the coupling member 19, and the legs 68 can be coupled to the coupling member 19 at their proximal ends instead of to the stud 74. In this example, when the stud 74 is pushed distally relative to the coupling member 19, the distal element 18 will close, while pulling the stud 74 proximally toward the coupling member 19 will open the distal element 18.

[0067] B. Fixing coverings on equipment

[0068] The fixation device 14 optionally includes a covering. The covering can help grasp the tissue and can later provide a surface for tissue ingrowth. The ingrowth of surrounding tissue (e.g., valve leaflets) provides stability to the device 14 as it further anchors it in place and can utilize natural tissue to cover the device, thereby reducing the possibility of an immune response. The covering can be composed of any biocompatible material, such as polyethylene terephthalate, polyester, cotton, polyurethane, expanded polytetrafluoroethylene (ePTFE), silicon, or various polymers or fibers, and have any suitable form, such as a fabric, mesh, textured weave, felt, annular, or porous structure. Typically, the covering has a low profile so as not to interfere with delivery through the introducer sheath or the leaflets or with grasping and engaging the tissue.

[0069] 17A to 17C The cover 100 is illustrated on a fixed device 14 with the device 14 in various positions. Figure 17A Shown is a cover 100 encapsulating distal element 18 and actuation mechanism 58 when device 14 is in the open position. Thus, engagement surface 50 is covered by cover 100, which helps minimize trauma to tissue and provides additional friction to help grasp and hold tissue. Figure 17B Shown in flipped position Figure 17A The cover 100 is loose-fitting and / or flexible or elastic so that the device 14 can be freely moved into various positions and the cover 100 conforms to the contours of the device 14 and remains securely attached in all positions. Figure 17CThe device 14 is shown in a closed position. Thus, when the fixation device 14 is left as an implant in the closed position, the exposed surfaces of the device 14 are substantially covered by the covering 100. It will be appreciated that the covering 100 can cover specific portions of the fixation device 14 while leaving other portions exposed. For example, the covering 100 can include a sleeve that fits over the distal element 18 instead of the actuation mechanism 58, a cap that fits over the distal end 54 of the distal element 18, or a pad that covers the engagement surface 50, to name a few. It will be appreciated that the covering 100 can allow any friction attachments (such as barbs) to be exposed. In addition, the covering 100 can cover the proximal element 16 and / or any other surface of the fixation device 14. In any case, the covering 100 should be durable to withstand multiple introduction cycles and, when implanted within the heart, a lifetime of cardiac cycles.

[0070] The covering 100 may alternatively be composed of a polymer or other suitable material that is impregnated, sprayed, coated, or otherwise adhered to the surface of the fixation device 14. Optionally, the polymer coating may include pores or contours to help grip tissue and / or promote tissue ingrowth.

[0071] Any covering 100 may optionally include a drug, antibiotic, antithrombotic, or antiplatelet agent, such as heparin, (COUMADIN) (warfarin sodium), to name a few. These agents can be, for example, impregnated into or coated on the covering 100. These agents can then be delivered to the surrounding tissue grasping tissue and / or bloodstream to achieve a therapeutic effect.

[0072] C. Improved Gripper Actuation

[0073] The above disclosure describes several variations of fixation devices and corresponding delivery devices for implanting fixation devices within native anatomical structures. It should be understood that the improved clamp actuation embodiments described in this section can be used in conjunction with the above referenced embodiments. Figures 1 to 17C Or any feature, attribute, method, or combination of variations described in other embodiments in this section. Figure 18An example of a fixation device 14 coupled to an interventional tool 10 is shown having a shaft 12, a delivery catheter 86 covered by a sleeve 87, and one or more tubing 90a, 90b passing through the delivery catheter 86. In some embodiments, it may be desirable to raise and lower the proximal elements 16a, 16b (also referred to as grippers) of the fixation device 14 and independently actuate them so that they are closer to or further away from their corresponding arms 53. As previously described, this can be accomplished by actuating gripper levers on a handle (not shown) to manipulate the snares or tubing 90a, 90b. Each lever can increase the tension on the corresponding tubing 90a, 90b (e.g., by pulling the lever upward) or reduce the tension on the tubing passing through the length of the delivery catheter 86 (e.g., by pushing the lever downward). As shown in the cross-sectional view, the delivery catheter 86 may include a central lumen 91 and secondary or peripheral lumens 92a, 92b, which are positioned on opposite sides of the extrusion cross-section to receive tubing 90a, 90b. In some examples, each of the tubing 92a, 92b can extend through a corresponding peripheral lumen, be coupled to a proximal element and be fixed to the shaft 12 at the end T1. After actuating the proximal element and / or implanting the fixation device, each of the tubing 92a, 92b can be decoupled from the shaft 12 (or a component near the shaft) so that the end T1 is disengaged from the proximal element and removed together with the delivery device. In some examples, the delivery catheter 86 includes two additional locking wire lumens 94a, 94b (shown in gray). The locking wire lumens 94a, 94b can receive a polymer tubing that pulls the linear harness of the fixation device 14 to lock and unlock the fixation device. The lockwire lumens 94a, 94b may be positioned along the neutral axis of the delivery catheter 86.

[0074] like Figure 18 As shown, when the catheter is bent to turn the fixation device 14 toward the mitral valve lesion or tricuspid valve lesion, the arc length of the peripheral lumen on or near the outer bend of the curve is longer than the neutral axis of the delivery catheter 86. On the other side of the cross section, the arc length of the peripheral lumen on or near the inner bend of the curve is shorter than the neutral axis of the delivery catheter. Figure 18 This difference in lumen arc length can result in a change in the slack of the tubing between the left proximal element 16a and the right proximal element 16b.

[0075] Uneven wire slack can affect grip performance when the delivery catheter is rotated with the peripheral lumen in the same plane as the bend plane, and this can occur particularly when the delivery catheter 86 and fixation device 14 need to be rotated to achieve perpendicularity along the line of coaptation when treating A1 / P1 or A3 / P3 mitral valve lesions, or when addressing the complex line of coaptation of the tricuspid valve with a fixation device. Uneven wire slack can also lead to sluggish or confusingly unresponsive proximal element actuation and / or performance issues (e.g., wire breakage) when actuating the proximal element.

[0076] In the example shown, a line 90a with little or no slack may not be able to fully or adequately drop the proximal element 16a to grasp the blade when the lever is actuated. In this example, the line 90a positioned over the outer curve would have reduced slack. When the "no slack" line 90a is tensioned, it may experience higher tensile loads and may be more susceptible to failure, especially if the fixation device is rotated to precisely position the line lumen over the outer curve.

[0077] Conversely, the tubing 90b on the inner bend may have excessive slack, which may prevent the proximal element 16b from fully raising when the user actuates the rod to its fully retracted position. This situation makes it difficult to grasp the blade because the proximal element 16b is not fully raised to make room for the blade to be inserted under the arm 53. In this case, the partially lowered proximal element 16b prevents the blade from entering the fixation device 14. In addition, this excessive slack situation similarly makes it difficult for the user to fully disengage the proximal element 16b from the blade if they need to attempt to release the blade in a subsequent re-grasp attempt. In addition, excessive slack can cause the tubing 90b to get stuck on the friction element, resulting in the following problems: difficulty in deploying / detaching the fixation device 14 from the delivery catheter 86, and / or an inability to fully lower the proximal element 16b.

[0078] It may be noted that in some examples, the uneven slack between the two lines begins to be corrected when the user rotates the fixation device 14 approximately 90 degrees. However, if the user rotates the fixation device 14 an additional 90 degrees (i.e., a total of 180 degrees), the lines' states reverse due to the difference in curvature of the delivery catheter at the inner and outer bends, such that the previously low-slack line becomes the high-slack line, and vice versa.

[0079] One solution to addressing the above-mentioned uneven relaxation and reducing the risk of proximal element actuation difficulties, pipeline jamming and / or pipeline breakage is to provide a delivery catheter 200 with a lumen having a defined curved path (e.g., a spiral path or a path twisted in a spiral shape within the body of the catheter 200). In some examples, the lumen is defined as a spiral path or in one or more curved paths that are wound uniformly or non-uniformly around a cylinder (e.g., a corkscrew shape). In some examples, the spiral path forms at least one complete rotation (e.g., 360 degrees) over a predetermined axial distance, and the distance can be selected as desired. The axial distance used to reach the rotation can be the same or different from other rotations. Additionally, the radius of the portion of the spiral path can be uniform or non-uniform. That is, the spiral path can be more tightly wound (e.g., with a smaller radius) from the proximal end to the distal end, and vice versa.

[0080] like Figure 19A As shown, a generally tubular delivery catheter 200 can include a body 205 (shown as transparent for ease of illustration) having a central lumen 209 and a plurality of peripheral lumens 210a, 210b and locking wire lumens 212a, 212b. This embodiment can be combined with any of the features, attributes, methods, or variations described in any of the aforementioned figures. In this example, each of the lumens defines a spiral or helical path defined within the body 205 (shown as transparent) of the delivery catheter 200, and the spiral paths are twisted relative to each other. In one example, the spacing between the peripheral lumens 210a, 210b and the locking wire lumens 212a, 212b is constant at each axial level or "slice" of the delivery catheter 200. In this configuration, no matter what shape or configuration the delivery catheter takes due to the spiral geometry of the path, each of the peripheral lumens 210a, 210b will be partially disposed on the outer curvature of the delivery catheter and partially disposed on the inner curvature of the delivery catheter. Without being bound by any particular theory, it is believed that the helical path ensures that sufficient slack is available in both lines coupled to the proximal elements regardless of the angle of rotation of the fixation device 14. For example, the helical path defined by each of the peripheral lumens 210a, 210b can be formed by twisting the extrusion during the extrusion process. In this example, two peripheral lumens 210a, 210b are formed, but it should be understood that any number of lumens can be used, including a single peripheral lumen, two peripheral lumens, three peripheral lumens, four peripheral lumens, or more peripheral lumens. The helical path can also be used to prevent kinks in the delivery catheter.

[0081] Figure 19BA series of cross sections of a delivery catheter 200 are illustrated. In this example, the first peripheral lumen 210a is shown in gray shading in each cross section to aid understanding of the present disclosure. As shown, in the first cross section, the first peripheral lumen 210a is set at the 0 degree position, and each continuous section is rotated approximately 15 degrees in the direction "R". In this example, each of the continuous sections is 1 mm apart so that the spiral path defined by the first peripheral lumen 210a rotates 15 degrees for every 2 mm of axial length. The degree to which each spiral path rotates over a predetermined axial length will define how "loosely wound" or "tightly wound" each spiral path will be. In some examples, the delivery catheter 200 can form a complete turn or rotation for every 30 mm to 50 mm of axial length. In some examples, the delivery catheter 200 can complete a total of 1 to 20 rotations (e.g., more than one rotation or more than five rotations) over its axial length. In other words, the delivery catheter can define a pitch, which is the axial distance between two consecutive rotations of the same peripheral lumen, and the pitch can be between 1 helical lumen rotation per inch and 2 helical lumen rotations per inch.

[0082] Now refer to Figure 20 , which shows an example of a fixation device 14 coupled to an interventional tool 10' having a shaft 12, a delivery catheter 200 covered by a sleeve 220, and one or more tubing 90a, 90b passing through the delivery catheter 200 to raise and lower the proximal elements 16a, 16b. In this example, the delivery catheter 200 includes a central lumen 209 and a plurality of peripheral lumens 210a, 210b defining respective spiral paths. The peripheral lumens 210a, 210b can be formed externally of the central lumen 209 along their respective entire lengths. In Figure 20 In the embodiment, for ease of illustration, the helical path of the peripheral lumen 210a is schematically shown in dashed lines, but it should be understood that in this example, four twisted helical paths are defined for the peripheral lumens 210a, 210b and the lock wire lumens 212a, 212b (see also FIG. Figure 19A In various examples, these spiral paths can be along the delivery catheter 200 ( Figure 20 ) along the entire length or along selected portions. In some examples, each peripheral lumen 210a, 210b forms at least one complete rotation. In some examples, each peripheral lumen 210a, 210b forms at least two or more complete rotations. In some examples, each peripheral lumen 210a, 210b forms at least one complete rotation or two or more rotations in the bendable section 230 of the delivery catheter 200. Figure 20, a schematic diagram is provided showing three cross-sections of the peripheral lumen 210a at different axial positions, with the peripheral lumen 210a at the 12 o'clock position in the first cross-section, at the 1 o'clock position in the second cross-section (e.g., rotated 30 degrees (+ / - 5 degrees) from the initial position), and at the 2 o'clock position in the third cross-section (e.g., rotated 60 degrees (+ / - 5 degrees) from the initial position). The peripheral lumen 210a is shown in gray shading only to aid understanding. It should be understood that each of the peripheral lumens 210a-210b can have the same diameter and shape as each other, or the same diameter and shape as the lock wire lumens 212a, 221b. Alternatively, in some examples, one or more of the peripheral lumens 210a, 120b can have a shape and / or diameter that is different from the other peripheral lumens or lock wire lumens. In at least some examples, each peripheral lumen 210a, 120b has a diameter between 0.005 inches and 0.020 inches (e.g., approximately 0.016 inches). In at least some examples, each peripheral lumen 210a, 120b has a diameter between 0.020 inches and 0.025 inches (e.g., approximately 0.024 inches). In at least some examples, each tubing has a diameter between 0.0040 inches and 0.0050 inches (e.g., approximately 0.0045 inches). In some examples, the ratio of the peripheral lumen diameter to the tubing diameter is between 3:1 and 6:1 (e.g., a 4:1 ratio).

[0083] Figure 21 A variation of a delivery catheter for use with examples of the present disclosure is shown in . In this example, the fixation device 14 is coupled to an interventional tool 10 ″ having a shaft 12, a delivery catheter 300 covered by a sleeve 320, and one or more lines 90a, 90b passing through the delivery catheter 300 to raise and lower the proximal elements 16a, 16b. In this example, the delivery catheter 300 includes a central lumen 309 formed in a body 305, two peripheral lumens 310a, 310b, and two locking wire lumens 312a, 312b. The peripheral lumens 310a, 310b and the two locking wire lumens 312a, 312b can be formed outside of the central lumen 309 along their respective entire lengths. The peripheral lumens 310a, 310b and the locking wire lumens 312a, 312b 19A to 20 The example of the embodiment of the invention differs in that each peripheral lumen 310a, 310b first defines a first linear path segment 315 through the distal-most segment 330a of the delivery catheter 300, then defines a helical path segment 316 in the bendable segment 330b, and then defines another or second linear path segment 317 in the proximal-most segment 330c. It should be noted that for ease of illustration, in Figure 21Only one complete path is shown in its entirety in FIG, but all paths may be similarly configured, but spaced about the body 305 such that the helical paths they define are twisted relative to each other (see also FIG. Figure 19A ). In turn, each path transitions from a straight path 315 to a spiral path 316 and then back to a straight path 317, with the spiral path being confined to the bendable section 330b of the delivery catheter 300. Without being bound by any particular theory, it is believed that this configuration can eliminate the risk of uneven relaxation while also minimizing any added friction within the delivery catheter by applying the spiral section only where needed (e.g., in areas that can bend).

[0084] It should be understood that the embodiments described herein are merely illustrations of the principles and applications of the present disclosure. For example, the system can include any number of peripheral lumens or any number of transitions between a spiral path and a straight path. In addition, the system can include spiral and non-spiral paths (including straight paths). In addition, some components are optional, and the present disclosure contemplates various configurations and combinations of elements disclosed herein. Therefore, it should be understood that various modifications can be made to the illustrative embodiments, and other arrangements can be designed without departing from the spirit and scope of the present disclosure as defined in the appended claims.

[0085] Although the present disclosure has been described herein with reference to specific embodiments, it should be understood that these embodiments are only intended to illustrate the principles and applications of the present disclosure. Therefore, it should be understood that various modifications may be made to the illustrative embodiments and other arrangements may be designed without departing from the spirit and scope of the present disclosure as defined in the appended claims.

Claims

1. An interventional tool comprising: a delivery catheter defining a central lumen and a plurality of peripheral lumens, at least one of the plurality of peripheral lumens defining a helical path along a portion of the delivery catheter; as well as At least one tubing is disposed within the at least one peripheral lumen of the plurality of peripheral lumens, the at least one tubing being configured to actuate a medical device. 2 . The interventional tool of claim 1 , wherein the plurality of peripheral lumens comprises two peripheral lumens equally spaced from each other, and the at least one tubing comprises two tubings.

3. The interventional tool of claim 2, wherein each of the two peripheral lumens extends along a corresponding helical path. The interventional tool of claim 1 , wherein the helical path is confined to a bendable section of the delivery catheter.

5. The interventional tool of claim 1, wherein the helical path extends along the entire length of the delivery catheter.

6. The interventional tool of claim 1, wherein the delivery catheter comprises a proximal-most section, a bendable section, and a distal-most section, the helical path of the at least one peripheral lumen being disposed within the bendable section.

7. The interventional tool of claim 6, wherein the at least one peripheral lumen extends along a first linear path in the proximal-most section and a second linear path in the distal-most section.

8. The interventional tool of claim 1, wherein the helical path of the at least one peripheral lumen has a pitch between 1 rotation per inch and 2 rotations per inch.

9. The interventional tool of claim 1, wherein the helical path of the at least one peripheral lumen forms more than one complete rotation.

10. The interventional tool of claim 1, wherein the helical path of the at least one peripheral lumen forms more than five complete rotations.

11. A system comprising: The interventional tool according to claim 1; as well as A medical device comprising two arms and two proximal elements, at least one of the proximal elements being coupled to the at least one line of the interventional tool.

12. The system of claim 11, wherein the at least one tubing line comprises two tubing lines, each of the two tubing lines being coupled to a selected one of the two proximal elements.

13. The system of claim 12, wherein the two lines comprise cables.

14. The system of claim 12, wherein the two lines are configured to actuate the two proximal elements to move the two proximal elements relative to the two arms.

15. The system of claim 11, wherein the medical device is a fixed device.

16. The system of claim 11, wherein the medical device is a mitral valve clip.

17. A method of actuating a medical device, comprising: providing an interventional tool comprising a delivery catheter defining a central lumen and a plurality of peripheral lumens, at least one of the plurality of peripheral lumens defining a helical path along a portion of the delivery catheter, at least one tubing being disposed within the at least one of the plurality of peripheral lumens; as well as The at least one line is pulled to actuate the medical device.

18. The method of claim 17, wherein the medical device comprises two arms and two proximal elements, and wherein pulling the at least one line comprises moving a first proximal element of the two proximal elements using the at least one line.

19. The method of claim 17, wherein the medical device comprises two arms and two proximal elements, wherein the at least one line comprises two lines, and wherein pulling the at least one line comprises independently moving each of the two proximal elements.

20. The method of claim 17, wherein the plurality of peripheral lumens comprises two peripheral lumens equally spaced from one another, and wherein pulling the at least one tubing comprises passing the at least one tubing through one of the two peripheral lumens.

Images